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1. Pirie, Angus D.; A light scattering study of colloid-polymer mixtures: Not known; A detailed light scattering study of non-equilibrium states found in a model colloid-polymer mixture is presented. Conventional light scattering is used to examine the average structure of the phase, over a wide range of wavevectors. For all non-equilibrium samples a 'ring' of scattered radiation is found at small angles, whose temporal evolution is used to investigate aggregation kinetics and the growth of structure. For low concentrations of colloid and just sufficient polymer to induce non-equilibrium behaviour a small angle ring is observed after a initial 'lag time', which remains stationary and brightens rapidly, behaviour reminiscent of classical nucleation. At higher colloid concentrations one finds a continuously collapsing and brightening ring, similar to that found in classical spinodal decomposition. Upon the addition of further polymer the system gels and the small angle ring becomes arrested at a finite wavevector. Direct visual observation of these different regimes is also presented, via video-enhanced microscopy and direct time-lapse video recordings, to complement the light scattering data. The particle dynamics within the aggregates are measured using dynamic light scattering, The results obtained suggest that the onset of non-equilibrium behaviour is caused by the presence of a metastable gas-liquid phase boundary, which can be calculated using a recently-developed mean-field theory. [Text] [View with Perseus links] (0.34)

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1. Gaier, J; Grandits, P.; Schachermayer, W.; Asymptotic ruin probalities and optimal investment: (in English) We study the infinite time ruin probability for an insurance company in the classical Cramer-Lundberg model with finite exponential moments. The additional non-classical feature is that the company is also allowed to invest in some stock market, modeled by geometric Brownian motion. We obtain an exact analogue of the classical estimate for the ruin probability without investment, i.e., an exponential inequality. The exponent is larger than the one obtained without investment, the classical Lundberg adjustment coefficient, and thus one gets a sharper bound on the ruin probability. A surprising result is that the trading strategy yielding the optimal asymptotic decay of the ruin probability simply consists in holding a fixed quantity (which can be explicitly calculated) in the risky asset, independent of the current reserve. This result is in apparent contradiction to the common believe that 'rich' companies should invest more in risky assets than 'poor' ones. The reason for this seemingly paradoxical result is that the minimization of the ruin probability is an extremely conservative optimization criterion, especially for 'rich' companies. (author's abstract), Working Paper, Wirtschaftsuniversitat Wien [Text] [View with Perseus links] (1.43)

2. Stix, Volker; Stochastic branch & bound applying target oriented branch & bound method to optimal scenario tree reduction: (in English) In this article a new branch & bound method is described. It uses an artificial target to improve its bounding capabilities. Therefore the new approach is faster compared to the classical one. It is applied to the stochastic problem of optimal scenario tree reduction. The aspects of global optimization are emphasized here. All necessary components for that problem are developed and some experimental results underline the benefits of the new approach. (author's abstract), Working Paper, Wirtschaftsuniversitat Wien [Text] [View with Perseus links] (0.87)

3. Schachermayer, Walter; Optimal investment in incomplete financial markets: (in English) We give a review of classical and recent results on maximization of expected utility for an investor who has the possibility of trading in a financial market. Emphasis will be given to the duality theory related to this convex optimization problem. For expository reasons we first consider the classical case where the underlying probability space is finite. This setting has the advantage that the technical diffculties of the proofs are reduced to a minimum, which allows for a clearer insight into the basic ideas, in particular the crucial role played by the Legendre-transform. In this setting we state and prove an existence and uniqueness theorem for the optimal investment strategy, and its relation to the dual problem; the latter consists in finding an equivalent martingale measure optimal with respect to the conjugate of the utility function. We also discuss economic interpretations of these theorems. We then pass to the general case of an arbitrage-free financial market modeled by an R^d-valued semi-martingale. In this case some regularity conditions have to be imposed in order to obtain an existence result for the primal problem of finding the optimal investment, as well as for a proper duality theory. It turns out that one may give a necessary and sufficient condition, namely a mild condition on the asymptotic behavior of the utility function, its so-called reasonable asymptotic elasticity. This property allows for an economic interpretation motivating the term "reasonable". The remarkable fact is that this regularity condition only pertains to the behavior of the utility function, while we do not have to impose any regularity conditions on the stochastic process modeling the financial market (to be precise: of course, we have to require the arbitrage-freeness of this process in a proper sense; also we have to assume in one of the cases considered below that this process is locally bounded; but otherwise it may be an arbitrary R^d-valued semi-martingale). (author's abstract), Working Paper, Wirtschaftsuniversitat Wien [Text] [View with Perseus links] (0.82)

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1 from Perseus Project Research Preprints

1. Gregory Crane; From Greece to Rome: Building a Roman Perseus: (in English) Forthcoming, Journal for the Association of Classical Teachers, 2000 [Text] (0.78)

2117 from Greek and Roman Materials

1. Art periods [Reference article in Perseus Encyclopedia] (15.76)

2. Harry Thurston Peck; Harpers Dictionary of Classical Antiquities (1898): (in English) [Text] (14.24)

3. The Princeton Encyclopedia of Classical Sites: Richard Stillwell, William L. MacDonald, Marian Holland McAllister; (in English) [Text] (14.24)

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2 from Renaissance Materials

1. Alexander Dyce; A General Glossary to Shakespeare's Works: (in English) Alexander Dyce, an important Nineteenth Century scholar, collector, bibliophile, and editor of classical and Renaissance literature, compiled this comprehensive dictionary of words used in Shakespeare's drama and poetry. Entries include definitions of words, as well as examples of usage from Shakespeare and other Renaissance writers. [Text] (14.24)

2. M. W. MacCallum; Shakespeare's Roman Plays and their Background: (in English) This is Mungo William MacCallum's landmark study of Shakespeare's Roman plays: Julius Caesar, Antony and Cleopatra, and Coriolanus. MacCallum (1854-1942), an eminent turn-of-the-century scholar, examines the plays, their relations to each other, and their development from classical and contemporary sources. [Text] (4.17)

1 from American Memory: Upper Midwest

1. Lucinda Hinsdale Stone, her life story and reminiscences. By Belle McArthur Perry ... Introduction by Ellen M. Henrotin: (in English) This is a collection of reminiscences of and about Lucinda Hinsdale Stone (1814-1900), one of Michigan's foremost spokespersons for coeducation and equal educational rights for women during the late nineteenth century. Born in Hinesburg, Vermont, she received a classical education as the first female graduate of Hinesburg Academy. After teaching at Burlington Seminary and, later, as a private tutor on a Mississippi plantation, she married James Andrus Blinn Stone, a Baptist minister. In 1843, Lucinda Stone took over a fledgling branch of the University of Michigan in Kalamazoo. There she began to teach women through a separate female department until she resigned in 1863 in a controversy over exposing students to literature considered inappropriate for ladies. She continued to teach most of her students out of her own home and eventually escorted women on guided study tours of Europe. As part of her efforts to educate women, she helped found the Ladies Library Association of Kalamazoo. In 1873, influenced by various New England women's clubs, she organized the first full-fledged women's club in Michigan. There are few details here about her later life, but there are abundant testimonials about her importance as a public speaker, journalist, and charter member of the Michigan Woman's Press Association. The book also includes abundant excerpts from Stone's writings about eminent people she encountered abroad and at home. [Text] (4.17)

65 from AIM25 - Archives in London

1. Souter | Alexander | 1873-1949 | Professor of New Testament Greek and Exegesis | Regius Professor of Humanity; SOUTER, Professor Alexander (1873-1949): Working papers of Alexander Souter, 1889-1930s and undated, comprising 20 notebooks, 1889-1913, on his studies in Aberdeen and Cambridge and on classical and patristic sources for his later work in Oxford, Aberdeen and Italy, and also including a diary for 1890, with entries noting work completed, news cuttings relating to his interests, and a book containing short publications such as Souter's The Predicative Dative Especially in Later Latin (1926) and A fragment of an unpublished Latin text of the Epistles to the Hebrews with a brief exposition (1924); manuscript texts for articles and lectures, mostly annotated with the dates and places of delivery, 1911-1936, including 'Classical Studies in the United States of America', 'Four Great Scholars', 'The Latin Bible', The History of Latin Lexicography', 'Statius: the Poet of the Silvae', 'Statius Silvae, with special reference to the manuscript tradition', 'Pelagius's Commentary on the Epistles of St Paul', 'Recent Advances in Palaeography', 'St Augustine', 'Recollections of a Travelling Scholar' and 'Beginnings of Christianity in Africa'; manuscript catalogue of editions of Latin authors in Souter's collection (1918). [Text] [View with Perseus links] (2.58)

2. Enk | Petrus Johannes | 1885-1960 | Professor of Latin; ENK, Professor Petrus Johannes (1885-1960): Papers of Enk, mainly comprising notebooks, relating to his work in school and college on classical texts and Latin literature, (predominantly 1894-1907), including notes on and partial translations into Dutch of the Annals of Publius Cornelius Tacitus, the Metamorphoses of Publius Ovidius Naso, the works of Marcus Tullius Cicero, the Elegiae of Sextus Propertius, the Carmina of Giovanni Pascoli; working papers, 1876-1923, of Enk's former teacher, Professor Jacobus Johannes Hartman of Leiden (1851-1924), mainly comprising notebooks and partial translations into Dutch, of the Adelphoe, Andria, and Hecyra of Publius Terentius Afer, the Epistulae Ex Ponto of Publius Ovidius Naso, the Aeneid of Publius Vergilius Maro, the Seven against Thebes of Aeschylus; notebook by Hartman entitled 'Adversaria Lucianen', 1876; manuscript topographical notebook by Hartman entitled 'Romeinsche Antiquiteiten', 1905; press cuttings and obituaries of Hartman (predominantly 1924); correspondence of Enk and Hartman with Dutch, English and German scholars of Latin, [1920s and 1930s]; photographs and illustrations of classical sculpture and architectural sites; typescript inventories of Enk's library of classical texts and pamphlets as at 1 Jun 1960. With bound manuscript of the Thebais by Publius Papinius Statius, in an Italian humanistic script of the late 15th century. [Text] [View with Perseus links] (2.09)

3. Ogden | Charles Kay | 1889-1957 | originator of Basic English and book-collector<BR>Knight | William Francis Jackson | 1895-1964 | classical scholar; Ogden Papers: Papers of Charles Kay Ogden, c1940-c1950, some undated, largely comprising correspondence (c40 items) on literary and other matters with William Francis Jackson Knight, mainly addressed to Ogden and dating from 1940-1943, the subjects including classical metre, Horace and Catullus. Other papers include notes by Ogden on Horace, Catullus, scansion, and other poetic subjects; three pamphlets on classical subjects, including Horace and Virgil, by Knight. [Text] [View with Perseus links] (2.00)

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6 from BioMed Central

1. James Stevens, Etienne Joly, John Trowsdale, Geoffrey Butcher; Peptide binding characteristics of the non-classical class Ib MHC molecule HLA-E assessed by a recombinant random peptide approach: (in English) AbstractBackgroundIncreasing evidence suggests that the effect of HLA-E on Natural Killer (NK) cell activity can be affected by the nature of the peptides bound to this non-classical, MHC class Ib molecule. However, its reduced cell surface expression, and until recently, the lack of specific monoclonal antibodies hinder studying the peptide-binding specificity HLA-E.ResultsAn in vitro refolding system was used to assess binding of recombinant HLA-E to either specific peptides or a nonamer random peptide library. Peptides eluted from HLA-E molecules refolded around the nonamer library were then used to determine a binding motif for HLA-E. Hydrophobic and non-charged amino acids were found to predominate along the peptide motif, with a leucine anchor at P9, but surprisingly there was no methionine preference at P2, as suggested by previous studies.ConclusionsCompared to the results obtained with rat classical class Ia MHC molecules, RT1-A1c and RT1-Au, HLA-E appears to refold around a random peptide library to reduced but detectable levels, suggesting that this molecule's specificity is tight but probably not as exquisite as has been previously suggested. This, and a previous report that it can associate with synthetic peptides carrying a viral sequence, suggests that HLA-E, similar to its mouse counterpart (Qa-1b), could possibly bind peptides different from MHC class I leader peptides and present them to T lymphocytes. [Text] [View with Perseus links] (0.79)

2. Michaela Struder-Kypke, Andre-Denis Wright, Cheryl Jerome, Denis Lynn; Parallel evolution of histophagy in ciliates of the genus Tetrahymena: (in English) AbstractBackgroundSpecies of Tetrahymena were grouped into three complexes based on morphological and life history traits: the pyriformis complex of microstomatous forms; the patula complex of microstome-macrostome transformers; and the rostrata complex of facultative and obligate histophages. We tested whether these three complexes are paraphyletic using the complete sequence of the small subunit rDNA (SSrDNA).ResultsIn addition to the 16 species of Tetrahymena whose SSrDNA sequences are known, we sequenced the complete SSrDNA from the following histophagous Tetrahymena species; Tetrahymena bergeri, Tetrahymena mobilis, Tetrahymena rostrata, and Tetrahymena setosa as well as the macrostome species Tetrahymena vorax. We also included a ciliate tentatively identified as Lambornella sp., a parasite of the mosquito Aedes sp. We confirmed earlier results using SSrDNA, which showed two distinct clusters of Tetrahymena species: the australis group and borealis group. The genetic distances among Tetrahymena are in general very small. However, all nodes were supported by high bootstrap values. With the exception of T. bergeri and T. corlissi, which are both histophagous and group as sister species, all other histophagous Tetrahymena species are most closely related to a bacterivorous species. Furthermore, Lambornella sp. and T. empidokyrea, both mosquito parasites, are sister species, although there is a considerable genetic distance between them.ConclusionsThere has been parallel evolution of histophagy in the genus Tetrahymena and the three classical species complexes are paraphyletic. As the genus Lambornella arises within the Tetrahymena clade, it is not likely a defensible one. [Text] [View with Perseus links] (0.29)

3. Yi Pei, Beate Schwer, Julia Saiz, Robert Fisher, Stewart Shuman; RNA triphosphatase is essential in Schizosaccharomyces pombe and Candida albicans: (in English) AbstractBackgroundThe first two steps in the capping of cellular mRNAs are catalyzed by the enzymes RNA triphosphatase and RNA guanylyltransferase. Although structural and mechanistic differences between fungal and mammalian RNA triphosphatases recommend this enzyme as a potential antifungal target, it has not been determined if RNA triphosphatase is essential for the growth of fungal species that cause human disease.ResultsWe show by classical genetic methods that the triphosphatase (Pct1) and guanylyltransferase (Pce1) components of the capping apparatus in the fission yeast Schizosaccharomyces pombe are essential for growth. We were unable to disrupt both alleles of the Candida albicans RNA triphosphatase gene CaCET1, implying that the RNA triphosphatase enzyme is also essential for growth of C. albicans, a human fungal pathogen.ConclusionsOur results provide the first genetic evidence that cap synthesis is essential for growth of an organism other than Saccharomyces cerevisiae and they validate RNA triphosphatase as a target for antifungal drug discovery. [Text] [View with Perseus links] (0.26)

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12 from CCSD th&egrave;ses-EN-ligne

1. Bertolin, Cristiana; Periodes et groupes de Mumford-Tate des 1-motifs: Dans la premiere partie de cette these, on etudie la structure et les degenerescences du groupe de Mumford-Tate d'un 1-motif $M$ defini sur $\CC$, $MT(M)$. Ce groupe est un $\QQ\,$-groupe algebrique qui agit sur la realisation de Hodge de $M$ et qui est muni d'une filtration croissante $W_\bullet$. On prouve que le radical unipotent de $MT(M)$, qui est $W_{-1}(MT(M)),$ s'injecte dans un groupe de Heisenberg generalise''. Ensuite on explique comment se reduire a l'etude du groupe de Mumford-Tate d'une somme directe de 1-motifs dont le groupe des caracteres du tore et dont le reseau sont de rang 1. Puis on classifie et on etudie les degenerescences de $MT(M)$, i.e. les phenomenes qui causent la chute de la dimension de $MT(M)$. Dans la deuxieme partie, on propose une conjecture de transcendence, qu'on appelle {\it conjecture elliptico-torique} (CET), et notre resultat principal est que (CET) {\it est equivalente a ${\rm (CPG)}_K$, appliquee aux 1-motifs de la forme $M=[ {\Bbb Z}^{r} \, {\buildrel u \over \longrightarrow} \,\prod^n_{j=1} {\cal E}_j \times {\GG}_m^s]$, ou les ${\cal E}_j$ sont des courbes elliptiques deux a deux non isogenes}. Notre conjecture (CET) implique des conjectures de transcendance classiques'', parmis lesquelles les plus fameuses sont les suivantes~: la conjecture de Schanuel, l'analogue elliptique de la conjecture de Schanuel, une conjecture modulaire qui generalise un theoreme de Y. Nesterenko, ... Mais a partir de (CET), on peut aussi construire d'autres conjectures de transcendance, qui, a ma connaissance, ne se trouvent pas dans la litterature. Chacune de ces conjectures, qui peuvent se deduire de (CET), est equivalente a ${\rm (CPG)}_K$ appliquee a un 1-motif bien choisi~: par exemple, la conjecture de Schanuel est equivalentes a ${\rm (CPG)}_K$ appliquee a des 1-motifs de la forme $M=[ {\Bbb Z}^{r} \, {\buildrel u \over \longrightarrow} \, {\GG}_m^s]$. ---------- In this thesis we study the structure and the degeneracies of the Mumford-Tate group of a 1-motive $M$ defined over $\CC$, $MT(M)$. This group is an algebraic $\QQ\,$-group acting on the Hodge realization of $M$ and endowed with an increasing filtration $W_\bullet$. We prove that the unipotent radical of $MT(M)$, which is $W_{-1}(MT(M)),$ injects into a generalized'' Heisenberg group. We then explain how to reduce to the study of the Mumford-Tate group of a direct sum of 1-motives whose torus's character group and whose lattice are both of rank 1. Next we classify and we study the degeneracies of $MT(M)$, i.e. those phenomena which imply the decrement of the dimension of $MT(M)$. The generalized Grothendieck's conjecture of periods ${\rm (CPG)}_K$ predicts that if $M$ is a 1-motive defined over an algebraically closed subfield $K$ of $\CC$, then $ {\rm deg.transc}_{\QQ}\, K ({\rm p\acute eriodes}(M))\geq \dim_{\QQ}MT( M_{\CC}).$ In the second part of this thesi we propose a conjecture of transcendance that we call {\it the elliptico-toric conjecture} (CET). Our main result is that (CET) is equivalent to ${\rm (CPG)}_K$ applied to 1-motives defined over $K$ of the kind $M=[ {\Bbb Z}^{r} \, {\buildrel u \over \longrightarrow} \,\prod^n_{j=1} {\cal E}_j \times {\GG}_m^s]$. (CET) implies some classical conjectures, as the Schanuel's conjecture or its elliptic analogue, but it implies new conjectures as well. All these conjectures following from (CET) are equivalent to ${\rm (CPG)}_K$ applied to well chosed 1-motives: for example the Schanuel's conjecture is equivalent to ${\rm (CPG)}_K$ applied to 1-motives of the kind $M=[ {\Bbb Z}^{r} \, {\buildrel u \over \longrightarrow} \, {\GG}_m^s]$. [Text] [View with Perseus links] (0.72)

2. DANIILIDIS, Aris; Analyse convexe et quasi-convexe ; applications en optimisation: Ce document de synthese s'articule autour de l'analyse convexe, de l'analyse quasi-convexe et des applications en optimisation. Dans le premier domaine on aborde les themes de la continuite, de la differentiabilite et des criteres de coincidence pour les fonctions convexes, puis la convexification des fonctions semi-continues inferieurement. Pour l'etude des fonctions quasi-convexes deux approches sont adoptees : une approche analytique, via un sous-differentiel generalise, et une approche geometrique, basee sur les normales aux tranches. La derniere partie est consacree a des applications a l'integration d'operateurs multivoques, aux inequations variationnelles et a des problemes d'optimisation multicriteres en dimension finie et infinie. Parmi les nouveautes de ce travail, on trouve la notion de monotonie fortement cyclique, qui caracterise le sous-differentiel d'une fonction convexe dont la restriction a son domaine est continue, la quasi-monotonie cyclique, qui est une propriete intrinseque du sous-differentiel d'une fonction quasi-convexe avec des applications importantes en economie mathematique, et la notion de quasi-monotonie propre, qui caracterise les operateurs pour lesquels l'inequation variationnelle associee a toujours des solutions sur toute sous-partie convexe et faiblement compacte de leur domaine. Notons encore une nouvelle caracterisation de la propriete de Radon-Nikodym, et une extension a la dimension infinie d'un resultat de Janin concernant l'integration d'un operateur maximal cycliquement sous-monotone, resultat qui generalise le theoreme classique de Rockafellar pour les operateurs maximaux cycliquement monotones. ---------- This document is a research contribution on Convex Analysis, on Generalized Convexity and on their applications in Optimization Theory. The first part deals with several fundamental questions concerning continuity, differentiability and criteria of coincidence for the class of convex functions. Convexification processes for lower semicontinuous functions are also studied. For the class of quasiconvex functions two approaches are used: an analytic approach, in the spirit of non-smooth analysis, and a geometric one, based on the notion of normal cones to sublevel sets. The second part is devoted to applications to the integration of multivalued operators, to Variational Inequality Problems and to finite and infinite dimensional multicriteria optimization problems. Among the concepts that are introduced for the first time in this work are: the notion of strong cyclic monotonicity, which characterizes the subdifferential of a convex function with a continuous restriction on its domain; the notion of cyclic quasimonotonicity, an intrinsic property of the subdifferentials of quasiconvex functions with important applications in Mathematical Economics; and the notion of proper quasimonotonicity, which characterizes the class of operators for which the associated Minty Variational Inequality problem has at least one solution on every nonempty convex and weakly compact subset of their domains. Let us finally mention a new characterization of the Radon-Nikodym property, and an extension to infinite dimensions of a result of Janin concerning the integration of the class of maximal cyclically submonotone operators, which generalizes a classical result of Rockafellar for maximal cyclically monotone operators. [Text] [View with Perseus links] (0.67)

3. TAILLEFER, Rachel; Theories homologiques des algebres de Hopf: Dans cette these, nous etudions des theories homologiques et cohomologiques adaptees aux algebres de Hopf. Dans un premier temps, nous unifions diverses theories cohomologiques pour les algebres de Hopf. Deux d'entre elles ont ete introduites par M. Gerstenhaber et S.D. Schack; l'une est sans coefficients et elle est liee a la cohomologie qui permet d'etudier les deformations d'une algebre de Hopf, l'autre est une theorie a coefficients (qui sont des bimodules de Hopf). La troisieme est une generalisation de la cohomologie qui a ete definie par C. Ospel, il s'agit aussi d'une theorie a coefficients. Pour unifier ces theories, nous les identifions au foncteur Ext sur une algebre associative definie par C. Cibils et M. Rosso qui est une algebre enveloppante'' associee a l'algebre de Hopf. Nous etablissons ensuite des formules explicites pour un cup-produit sur deux de ces cohomologies, et montrons que ce produit correspond au produit de Yoneda des extensions. Nous montrons aussi la Morita invariance de ces cohomologies. La deuxieme partie de la these est consacree a l'etude d'une homologie cyclique pour les algebres de Hopf. Il s'agit d'une version duale de la cohomologie qu'ont introduite A. Connes et H. Moscovici. Nous en etudions des proprietes, puis considerons le cas des algebres de groupe. Nous interpretons certaines decompositions (de Burghelea et de Karoubi-Villamayor) de l'homologie cyclique classique d'une algebre de groupe en termes d'homologie cyclique de Connes et Moscovici. Nous etablissons ensuite une formule de decomposition (semblable a celle de Karoubi-Villamayor) de l'homologie cyclique d'une algebre de Hopf cocommutative (qui generalise un resultat de Khalkhali et Rangipour). Enfin, nous calculons quelques exemples d'homologies: l'homologie cyclique classique des algebres de carquois tronquees, ainsi que l'homologie cyclique de Connes et Moscovici dans le cas particulier des algebres de Taft. Nous calculons aussi l'homologie de Hochschild et l'homologie cyclique classique des algebres d'Auslander des algebres de Taft. ---------- In this thesis, we study homological and cohomological theories adapted to Hopf algebras. In the first part, we unify various cohomological theories for Hopf algebras. Two of them were introduced by M. Gerstenhaber and S.D. Schack; one is without coefficients and is related to the cohomology adapted to the study of deformations of Hopf algebras, the other is a theory with coefficients (they are Hopf bimodules). The third is a generalization of the cohomology which was defined by C. Ospel, it is also a theory with coefficients. To unify these theories, we identify them with the Ext functor on an associative algebra defined by C. Cibils and M. Rosso which is an enveloping algebra' associated to the Hopf algebra. Next, we establish explicit formulae for a cup-product on two of these cohomologies, and prove that this product corresponds to the Yoneda product of extensions.We also prove Morita invariance for these cohomologies. The second part of the thesis is devoted to the study of a cyclic homology for Hopf algebras. It is dual to the cyclic cohomology introduced by A. Connes and H. Moscovici. We study some properties, then consider the case of group algebras. We interpret some decompositions (those of Burghelea and Karoubi-Villamayor) of the classical cyclic homology of group algebras in terms of Connes and Moscovici's cyclic homology of Hopf algebras. Then, we establish a decomposition formula (similar to that of Karoubi-Villamayor) for the cyclic homology of a cocommutative Hopf algebra (which generalizes a result of Khalkhali and Rangipour). Finally, we compute some examples of homologies: the classical cyclic homology of truncated quiver algebras, as well as Connes and Moscovici's cyclic homology in the special case of the Taft algebras, and the Hochschild and classical cyclic homologies of the Auslander algebras of the Taft algebras. [Text] [View with Perseus links] (0.37)

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583 from CIMI Metadata Harvesting Working Group Demonstration Repository

1. BADGER, Rick; Classical Myth II: BADGER, Rick; (in English) coloured inks on paper / Signed in pencil: Rick Badger 1981; Classical Myth II; 5/14 at lower right [Text] (3.46)

2. BADGER, Rick; Classical myth II: BADGER, Rick; (in English) coloured inks on paper support / Signed in pencil: Rick Badger 1981; Classical Myth II; /14 at lower left [Text] (2.77)

3. A. Rampant Walter; Certificate - Melbourne International Exhibition [Prof. F. McCoy]: to Professor Frederick McCoy (then Director of the National Museum of Victoria) 'for Services' associated with the 1880-1881 Melbourne International Exhibition. The certificate, designed by A. Rampant Walter of Melbourne, and printed by Hamel & Ferguson, has an ornate border with the names of countries and colonies which exhibited in the Exhibition, as well as various coats of arms. The four corners are occupied by the arms of United Kingdom, France, Italy and Germany. In centre top two female figures support the coat of arms of Victoria. The crest is part of an arch supported by pillars made from two sculptured females in classical dress with laurel branches; the left pillar is supported by "Wool", with tools of agriculture like shears, mattock, and a further female figure is seated at the base of the pillar. The right pillar is supported on 'Gold'. At the base of the arch, children in classical undress are shown working, play- ing and creating. At the top of the arch are further classical scenes, includ- ing a chariot and oxen drawing a wooden plough. Red paper seal in lower centre. [Text] (2.54)

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2 from California Digital Library Repository 1

1. Huber, Joel, Train, Kenneth; On the Similarity of Classical and Bayesian Estimates of Individual Mean Partworths: An exciting development in modeling has been the ability to estimate reliable individual-level parameters for choice models. Individual partworths derived from these parameters have been very useful in segmentation, identifying extreme individuals, and in creating appropriate choice simulators. In marketing, hierarchical Bayes models have taken the lead in combining information about the aggregate distribution of tastes with the individual's choices to arrive at a conditional estimate of the individual's parameters. In economics, the same behavioral model has been derived from a classical rather than a Bayesian perspective. That is, instead of Gibbs sampling, the method of maximum simulated likelihood provides estimates of both the aggregate and the individual parameters. This paper explores the similarities and differences between classical and Bayesian methods and shows that they result in virtually equivalent conditional estimates of partworths for customers. Thus, the choice between Bayesian and classical estimation becomes one of implementation convenience and philosophical orientation, rather than pragmatic usefulness. [Text] [View with Perseus links] (1.24)

2. Lopez-Cordova, J. Ernesto, Meissner, Chris; Exchange-Rate Regimes and International Trade: Evidence from the Classical Gold Standard Era: In this paper we show that the spread of the classical gold standard in the late nineteenth century increased international trade flows. This positive effect was compounded whenever a group of countries formed a monetary union. Applying the gravity model of trade to more than 1,100 country pairs during the 1870-1910 period, we find that two countries on gold would trade 60 percent more with each other than with countries on a different monetary standard. Moreover, a monetary union would more than double bilateral trade flows. Our findings are relevant for current discussions on alternative monetary arrangements for the twenty-first century. [Text] [View with Perseus links] (0.73)

3 from Caltech Computer Science Technical Reports

1. Chen, Min, Arvo, James; Closed-Form Expressions for Irradiance from Non-Uniform Lambertian Luminaires Part I: Linearly-Varying Radiant Exitance: We present a closed-form expression for the irradiance at a point on a surface due to an arbitrary polygonal Lambertian lurninaire with linearly-varying radiant exitance. The solution consists of elementary functions and a single well-behaved special function that can be either approximated directly or computed exactly in terms of classical special functions such as Clausen's integral or the closely related dilogarithm. We first provide a general boundary integral that applies to all planar luminaires and then derive the closed-form expression that applies to arbitrary polygons, which is the result most relevant for global illumination. Our approach is to express the problem as an integral of a simple class of rational functions over regions of the sphere, and to convert the surface integral to a boundary integral using a generalization of irradiance tensors. The result extends the class of available closed-form expressions for computing direct radiative transfer from finite areas to differential areas. We provide an outline of the derivation, a detailed proof of the resulting formula, and complete pseudo-code of the resulting algorithm. Finally, we demonstrate the validity of our algorithm by comparison with Monte Carlo. While there are direct applications of this work, it is primarily of theoretical interest as it introduces much of the machinery needed to derive closed-form solutions for the general case of luminaires with radiance distributions that vary polynomially in both position and direction. [Text] [View with Perseus links] (1.23)

2. Chen, Min; Perturbation Methods for Image Synthesis: This thesis presents new mathematical and computational tools for applying perturbation methods to image synthesis. The key idea is to characterize families of closely related optical paths by expanding a given path into a high-dimensional Taylor series. Our methods are based on the closed-form expressions for linear and higher-order approximations of specularly reflected rays of light, which are derived from the Implicit Function Theorem and Fermat's Variation Principle. The expressions hold for general multiple-bounce specular paths and provide a mathematical foundation for exploiting path coherence in incremental rendering. To illustrate their use, new algorithms based on the perturbation formulas are developed for several applications, including fast approximation of specular reflections on curved surface and direct caustic contour generation. First, path Jacobians are introduced to formulate the linear perturbation of a ray path connecting a fixed point and a perturbed point through any number of intermediate reflection points. These Jacobian matrices are the derivatives of the reflection points with respect to the perturbed endpoint. A recurrence relation is derived to compute the closed-form expressions of path Jacobians for a general multiple-bounce reflection path, even when the new reflection path cannot be expressed in a closed form. Next, the concept of path Jacobian is generalized to tensors of third order, which we call path Hessians. A simiar recurrence formula for path Hessians is derived from tensor calculus. The expressions for path Jacobians and path Hessians hold for any reflection path involving implicitly-defined reflective surfaces. Based on the close-form expressions for the path Jacobian and the path Hessian, a reflection path can be expanded as a Taylor series up to the second order. This perturbation formula gives rise to a fast and accurate interpolation scheme for the unknown reflection paths nearby. Finally, new algorithms are presented for some applications that will benefit from our perturbation method. In one application, a new approach is presented for interactively approximating specular reflections in arbitrary curved surfaces. The technique is quite general as it employs local perturbations to interpolate point samples and is applicable to any smooth implicitly-defined reflecting surface that is equipped with a ray-intersection procedure. After ray tracing a sparse set of reflection paths with respect to a given vantage point and static reflecting surfaces, the algorithm rapidly approximates reflections of arbitrary points in 3-space by expressing them as perturbations of nearby points with known reflections. The reflection of each new point is approximated to second-order accuracy using the Taylor expansions of one or more nearby reflection paths. After preprocessing, the approach is fast and accurate enough to compute specular reflections of tessellated objects in arbitrary curved surfaces at interactive rates using standard graphics hardware. In another application, the path Jacobian formula is used to directly compute caustic contours on a plane formed by a given point light source and an implicitly-defined specular surface. Caustic irradiance for a given point on the plane is computed using wavefront tracing and some classical results from differential geometry. Using the closed-form expression for path Jacobian, an analytic formula for the gradient of caustic irradiance is also derived. The level curves with constant caustic irradiance on the plane, caustic contours, are traced by numerically solving an isolux ordinary differential equation. [Text] [View with Perseus links] (0.28)

3. Leino, K. Rustan M.; Towards Reliable Modular Programs: Software is being applied in an ever-increasing number of areas. Computer programs and systems are becoming more complex and consisting of more delicately interconnected components. Errors surfacing in programs are still a conspicuous and costly problem. It's about time we employ some techniques that guide us toward higher reliability of practical programs. The goal of this thesis is just that. This thesis presents a theory for verifying programs based on Dijkstra's weakest-precondition calculus. A variety of program paradigms used in practice, such as exceptions, procedures, object orientation, and modularity, are dealt with. The thesis sheds new light on the theory behind programs with exceptions. It develops an elegant algebra, and shows it to be the foundation on which the semantics of exceptions rests. It develops a trace semantics for programs with exceptions, from which the weakest-precondition semantics is derived. It also proves a theorem on programming methodology relating to exceptions, and applies this theorem in the novel derivation of a simple program. The thesis presents a simple model for object-oriented data types, in which concerns have been separated, resulting in the simplicity of the model. To deal with large programs, this thesis takes a practical look at modularity and abstraction. It reveals a problem that arises in writing specifications for modular programs where previous techniques fail. The thesis introduces a new specification construct that solves that problem, and gives a formal proof of soundness for modular verification using that construct. The model is a generalization of Hoare's classical data refinement. However, there are more problems to be solved. The thesis reports on some of these problems and suggests some future directions toward more reliable modular programs. [Text] [View with Perseus links] (0.23)

7 from Caltech Earthquake Engineering Research Laboratory Technical Reports

1. Chiang, Dar-Yun; Parsimonious modeling of inelastic systems: Analytical modeling of one-dimensional hysteresis and general multi-axial cyclic plasticity is studied, with particular emphasis on the parsimony of model parameters and the physical consistency of model behavior. General criteria for good models are proposed to provide guidelines to the modeling studies conducted in this research. Various one-dimensional hysteretic models are examined in detail, including both deteriorating and non-deteriorating models. A general formulation for modeling of degrading systems is presented based on the formulation of the Distributed-Element Model (DEM) and the introduction of a damage index function. A new class of deteriorating Masing models, whose behavior can be completely described by a few simple mathematical rules and the extended Masing rules, is also developed to substitute for a special class of deteriorating DEMs, so that their applicabilty to system identification studies is improved. The one-dimensional DEMs are extended to the multi-dimensional case for constitutive modeling of cyclic plasticity, while preserving the concept of modeling plasticity by an assemblage of simple ideal elasto-plastic elements. In the generalization, a new invariant-yield-surface theory is proposed, in which no kinematic hardening rule is needed to account for the subsequent yielding and strain hardening behavior. A general theory is also developed to elucidate some important properties of material behavior based on the proposed multi-dimensional DEMs. The establishment of the theory provides instructive insight into the elastic-plastic response mechanisms of real materials under complicated loading conditions. Based on the insight, the Masing rules for one-dimensional hysteresis are extended to the multi-dimensional case by introducing a composition of plane-geometry transformations to a response formula developed for initial loading. This transformation method serves as an efficient way of implementing the classical multi-yield-surface theory with the Mroz kinematic hardening rule. Validity of the new formulations are confirmed by comparison with experimental results from the literature. [Text] [View with Perseus links] (0.86)

2. Bielak, Jacobo; Earthquake response of building-foundation systems: The influence of a deformable foundation on the response of buildings to earthquake motion is examined. The study is divided into two parts; the vibration of the base of the building on the foundation medium, and the response of the whole building-foundation system. Studied first are the forced horizontal, rocking and vertical harmonic oscillations of a rigid disc bonded to an elastic half-space, which is considered as a mathematical model for the soil. The problem, formulated in terms of dual integral equations, is reduced to a system of Fredholm integral equations of the second kind. For the limiting static case these equations yield a closed form solution in agreement with that obtained by others. Using the force-deflection relations for the base, the equations of motion of linear building-foundation systems are solved by both direct and transform methods. It is shown that, under assumptions which appear to be physically reasonable, the earthquake response of the interaction system reduces to the linear superposition of the responses of damped, linear one-degree-of-freedom oscillators subjected to modified excitations. This result is valid even for systems that do not possess classical normal modes. Explicit approximations in terms of the parameters of the system are obtained for the dynamic properties of the one-degree-of -freedom oscillator which is equivalent to a single story building -foundation system. For multi-story buildings it is shown that the effect of an elastic foundation, as measured by the change in the natural frequencies of the building, is negligible for modes higher than the first for many types of building structures. [Text] [View with Perseus links] (0.40)

3. Jennings, Paul C; Dynamics of building-soil interaction: In this study of the dynamics of building-soil interaction, the soil is modeled by a linear elastic half-space, and the building structure by an n-degree-of-freedom oscillator. Both earthquake response and steady-state response to sinusoidal excitation are examined. By assuming that the interaction system possesses n + 2 significant resonant frequencies, the response of the system is reduced to the superposition of the responses of damped linear oscillators subjected to modified excitations. The results are valid even though the interaction systems do not possess classical normal modes. For the special cases of single-story systems and the first modes of n-story systems, simplified approximate formulas are developed for the modified natural frequency and damping ratio, and for the modified excitation. Example calculations are carried out by the approximate and more exact analysis for one-story, two-story and ten-story interaction systems. The results show that interaction tends to decrease all resonant frequencies, but that the effects are often significant only for the fundamental mode for many n-story structures and are more pronounced for rocking than for translation. If the fixed-base structure has damping, the effects of interaction on the earthquake responses are not always conservative, and an increase or decrease in the response can occur, depending on the parameters of the system. [Text] [View with Perseus links] (0.23)

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2 from Caltech Electronic Theses and Dissertations

1. Shan, Jerry Wei-Jen; Mixing and Isosurface Geometry in Turbulent Transverse Jets: Paul Dimotakis, Morteza Gharib, Han Hornung, Anthony Leonard; (in English) Mixing and the geometry of jet-fluid-concentration level sets in turbulent transverse jets were experimentally studied. Jet-fluid concentration fields were measured with laser-induced fluorescence and digital imaging techniques for Reynolds numbers between 1000 and 20000. The scalar field is assessed in terms of classical measures, such as two-dimensional power spectra, as well as probability-density functions (PDFs). Enhanced scalar mixing with increasing Reynolds number is found in the evolution of PDFs of jet-fluid concentration. In the far field of the transverse jet, the scalar PDF is seen to evolve from a monotonically-decreasing function to a strongly-peaked distribution with increasing Reynolds number. Turbulent mixing is found to be flow dependent, based on differences between PDFs of scalar fields in transverse jets and axisymmetric, turbulent jets. The distribution of scalar increments is also studied for separations of varying distance and direction. A novel technique for whole-field measurement of scalar increments is introduced. Probability-density functions of scalar increments are found to trend toward exponential-tailed distributions with decreasing separation distances. The scalar field is anisotropic with decreasing scale, as seen in the two-dimensional power spectra, directional scalar microscales, and in directional PDFs of scalar increments. The geometric complexity of level-sets (iso-concentration contours) in turbulent mixing is assessed within the framework of fractal geometry. Generalized coverage statistics are introduced for anisotropic, non-self-similar geometries. This generalized coverage counting involves covering with parallelepipeds of varying size and aspect ratio. A scale-dependent measure of the anisotropy of a set is also introduced. It is shown that this scale-dependent measure transforms the generalized coverage count to isotropy through a scale-dependent normalization of the coordinates. Level sets of jet-fluid concentration in the transverse jet are found to be anisotropic at both large and small scales. The small-scale anisotropy is explained by vertically-oriented extensional strain caused by a counter-rotating vortex pair, while the large-scale anisotropy is associated with the horizontally-elongated shape of the cross-section of the transverse jet. For the special case of isotropic box-counting, the scale-dependent coverage dimension is found to vary from unity, at the smallest length scales, to 2, at the largest length scales, indicating that the isosurfaces produced by turbulent mixing are more complex than can be described by power-law fractals. [Text] [View with Perseus links] (0.34)

2. Burcsu, Eric; Investigation of Large Strain Actuation in Barium Titanate: Prof. Sossina M. Haile, Prof. Michael Ortiz, Prof. Kaushik Bhattacharya, Prof. Ares Rosakis, Prof. G. Ravichandran; (in English) Sensors and actuators based on ferroelectric materials have become indispensable in the fields of aerospace, high technology, and medical instruments. Most devices rely on the linear piezoelectric behavior of formulations of PZT which offer high bandwidth, linear actuation but very low strains of around 0.1%. The nonlinear electromechanical behavior of these materials is largely governed by the motion of domains and is highly affected by stress as well as electric field. The recent theories of Shu and Bhattacharya have sought to address some of the issues related to the structure and behavior of these materials at the mesoscale. One result of the theories is the prediction of another mode of actuation in ferroelectric crystals based on a combined electrical and mechanical loading that could result in strains of up to 6%. Descriptions of the phenomenological theories of ferroelectrics are presented including the classical Landau-Ginsburg-Devonshire theory and the more recent theory of Shu and Bhattacharya. Predictions are made, based on the theory, of the electromechanical behavior of ferroelectric crystals that are addressed by the experiments. An experimental setup has been designed to investigate large strain actuation in single crystal ferroelectrics based on combined electrical and mechanical loading. An investigation of the stress dependence of the electrostrictive response has been carried out with in situ observations of the domain patterns under constant compressive stress and variable electric field. Experiments have been performed on initially single domain crystals of barium titanate with (100) and (001) orientation at compressive stresses between 0 and 5 MPa. Global strain and polarization histories have been recorded. The electrostrictive response is shown to be highly dependent on the level of applied stress with a maximum strain of 0.9% measured at a compressive stress of about 2 MPa. An unusual secondary hysteresis has been observed in the polarization signal at high levels of stress that indicates an intermediate structural configuration, possibly the orthorhombic state. Polarized light microscopy has been used to observe the evolution of the domain pattern simultaneously with the strain and polarization measurement. These results are discussed and suggestions for future work are proposed. [Text] [View with Perseus links] (0.16)

15 from Chemistry Preprint Server

1. Zoltan Lukacs; An alternative theory of electrochemical kinetics: In the classical theory of electrochemical kinetics, the basic current - potential relationships of Tafel, Stern - Geary, Butler - Volmer - Erdey-Gruz are based on the assumption that the rate - determining step of the overall redox reaction is the charge transfer. In contrast, the theory outlined in this paper assumes that the charge - transfer step is always very near to equilibrium, and in the simplest and most general cases the preceding solvate sphere reorganisation - desolvation - adsorption and / or the proceeding solvation - desorption steps are rate - determining steps. The Maxwell - Boltzmann distribution formula is applied to the ratio of the surface concentrations of the activated redox reactants, to obtain the Nernst equation for the state of equilibrium, and the general differential equations of the kinetic system for non-equilibrium conditions. The explicit current - potential and impedance - frequency relationships are presented for various cases. The solution of the kinetic differential equation system is very simple for a potentiostatic single-step transient, and this formula provides an experimental possibility of testing the classical theory against the alternative theory. The experimental results are in contradiction with the classical theory and, in this sense, they are in favour of the alternative theory. [Text] [View with Perseus links] (0.93)

2. SIMEON Fabrice; ALDOL REACTION IN THE CYCLOHEPTANYL SERIES : SCOPE AND LIMITATIONS: Cycloheptanone reacts with aromatic aldehydes in basic media to give diarylidene-cycloheptanones. Low yields and selectivities are observed with the use of 2.0 equivalents of MeONa or NaOH, the reaction leading to 1a-c and variable amounts of mixtures of isomers 2a-c and monosubstituted compounds of type 3. However, the use of KOH and alsmot the unprecedent use of CsOH gave yields over 75 %. At least, it as been observed that the use of catalytic amounts (20 %) of BMPTO either by microwave or classical heating gave yields up to 90 %. This catalyst ledto high yields of exclusively compounds 1a-c of the E,E configuration in 15 to 20 min irradiation. [Text] [View with Perseus links] (0.72)

3. Eric Bittner, Jeremy Maddox; Quantum dissipation in unbounded systems: In recent years trajectory based methodologies have become increasingly popular for evaluating the time evolution of quantum systems. A revival of the de Broglie Bohm interpretation of quantum mechanics has spawned several such techniques for examining quantum dynamics from a hydrodynamic perspective. Using techniques similar to those found in computational fluid dynamics one can construct the wavefunction of a quantum system at any time from the trajectories of a discrete ensemble of hydrodynamic fluid elements (Bohm particles) which evolve according to non-classical equations of motion. Until very recently these schemes have been limited to closed systems. In this paper we present our methodology for including the effects of a thermal environment into the hydrodynamic formulation of quantum dynamics. We derive hydrodynamic equations of motion from the Caldeira-Leggett master equation for the reduced density matrix and give a brief overview of our computational scheme which incorporates an adaptive Lagrangian mesh. Our applications focus upon the dissipative dynamics of open unbounded quantum systems. Using both the Wigner phase space representation and the linear entropy we probe the breakdown of the Markov approximation of the bath dynamics at low temperatures. We suggest a criteria for rationalizing the validity of the Markov approximation in open unbound systems and discuss decoherence, energy relaxation, and quantum/classical correspondence in the context of the Bohmian paths. [Text] [View with Perseus links] (0.62)

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32 from CogPrints

1. Bullock, Theodore; Revisiting the Concept of Identifiable Neurons: Although eutely in nematodes was known, giant neurons in several taxa and unique motor neurons to leg muscles in decapod crustaceans, the idea that many animals have many identifiable neurons with relatively consistent dynamical properties and connections was only slowly established in the late 1960s and early 1970s. This has to be one of the important quiet revolutions in neurobiology. It stimulated a vast acquisition of specific information and led to some euphoria in the degree and pace of understanding activity of nervous systems and consequent behavior in terms of neuronal connections and properties. Some implications, problems and opportunities for new discovery are developed. The distribution of identifiable neurons among taxa and parts of the nervous system is not yet satisfactorily known. Their evolution may have been a case of several independent inventions. The degree of consistency has been quantified only in a few examples and the plasticity is little known. Identified neurons imply identifiable circuits but whether this extends to discrete systems, functionally definable, seems likely to have several answers in different animals or sites. Very limited attempts have been made to extend the concept to cases of two or ten or a hundred fully equivalent neurons, on all kinds of criteria. These attempts suggest a much smaller redundancy and vaster number of types of neurons than hitherto believed. Theory as well as empirical information has not yet interpreted the range of systems from those with small sets of relatively reliable neurons to those with large numbers of parallel, partially redundant units. The now classical notion of local circuits has to be extended to take account and find roles for the plethora of integrative variables, of evidence for neural processing independent of spikes and classical synapses, of spatial configurations of terminal arbors and dendritic geometry, of modulators and transmitters, degrees of rhythmicity (regularity varying several orders of magnitude), and of synchrony. Adequate language and models need to go beyond "circuits" in any engineering sense. Identifiable neurons can contribute to a broad spectrum of issues in neurobiology. [Text] [View with Perseus links] (1.21)

2. Bieberich, Erhard; What the liar paradox can reveal about the structure of our minds: In human consciousness perceptions are distinct or atomistic events despite being perceived by an apparently undivided inner observer. This paper applies both classical (Boolean) and quantum logic to analysis of the Liar paradox which is taken as a typical example of a self-referential negation in the perception space of an undivided observer. The conception of self-referential paradoxes is a unique ability of the human mind still lacking an explanation on the basis of logic. It will be shown that both classical and quantum logics fail to resolve the paradox because of the particle-like (atomistic) nature of physical events in the moments of perception. The atomistic reality is the only one observed in human consciousness even if, as has been claimed by a number of authors, consciousness arises from a quantum mechanical superposition. However, a computational solution of the paradox can be achieved by embedding quantum registers in a fractal space. The truth values, or q-bit eigenstates, of the separate parts of the paradox correspond to sub-spaces of the fractal. Since a fractal contains the whole in each part a self-referential negation emerges as the experienced concept in each sub-space. Fractal quantum computation is realized by a cNOT-operation with percolation of the control q-bits into sub-spaces of a nascent fractal. In other words, atomism cannot cope with a self-referential paradox but quantum logic gates embedded in a fractal structure can cope. Remarkably, it will be shown that a mind operating on these algorithmic principles will not inevitably be limited by Turing's halting theorem. I suggest a physical mechanism that can deal with our experience of self-referential paradox. Because it is also shown that this cannot be achieved by any previously suggested classical or quantum mechanical operation, the newly proposed mechanism provides a better model than others for an important aspect of the structure of our minds. [Text] [View with Perseus links] (0.98)

3. Blaha, Stephen; A Classical Probabilistic Computer Model of Consciousness: We show that human consciousness can be modeled as a classical (not quantum) probabilistic computer. A quantum computer representation does not appear to be indicated because no known feature of consciousness depends on Planck's constant h, the telltale sign of quantum phenomena. It is argued that the facets of consciousness are describable by an object-oriented design with dynamically defined classes and objects. A comparison to economic theory is also made. We argue consciousness may also have redundant, protective mechanisms. [Text] [View with Perseus links] (0.96)

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4 from DUETT - Dissertations and other Documents of the Gerhard-Mercator-University Duisburg

1. Hinzke, Denise; Computersimulationen zur Dynamik magnetischer Nanostrukturen - Computersimulations of the dynamics of magnetic nanostructures: Prof. Dr. Dietrich E. Wolf, Prof. Dr. Klaus D. Usadel; (in German) Magnetic nanostructures play a crucial role for the research in information technology, since magnetic materials are controllable on a nanometer scale. With decreasing size novel physical effects are observed which cannot be explained by means of theories describing macroscopic ferromagnets. In particular the understanding of the influence of finite temperatures on the reversal behavior and the magnetic stability of nanostructures is of broad interest since these aspects are very important for the development of new magnetic storage devices. This work gives an overview of numerical methods basing on a classical spin model. With the aid of these methods thermal activation processes can be investigated. The numerical solution of the Landau-Lifshtiz-Gilbert equation with Langevin dynamics as well as the Monte Carlo method with a so-called quantified time step is presented. This new procedure maps the quasi time scale of a Monte Carlo simulation on a realistic time scale. In this work activated magnetization processes in different kinds of nanostructures are investigated. Besides the investigation of fast switching processes, mainly the long-time behavior of elongated particles is studied. In these models different reversal mechanisms like coherent rotation, nucleation and curling can be observed depending on the sample geometry and the material parameters. In the one dimensional case, analytical asymptotic solutions for the energy barrier and the characteristic time exist, so that this model is convenient for testing the developed numerical methods. The implementation of the Fast Fourier Transformation method in the Monte Carlo method as well as the interpretation of the classical spin model in the sense of the continuums theory allows for a computer simulation of realistic systems. An application is the investigation of thermally activated reversal processes in nanowires during a hysteresis loop. The insights in the occurring reversal modes give information about the expected magnetoresistance. The results of these numerical investigations are compatible with the data from experimental observations of Conanowires. [Text] [View with Perseus links] (0.62)

2. Hucht, Alfred; Temperaturabhangigkeit magnetischer Anisotropien in ultradunnen Filmen - Temperature dependence of magnetic anisotropies in ultra-thin films: Prof. Dr. rer.nat. Peter Entel, Prof. Dr. rer.nat. Klaus Usadel; (in German) Anisotropies essentially affect magnetism in thin ferromagnetic films of few atomic layers. On the one hand they can stabilize long range order in these systems, on the other hand they strongly influence the orientation of magnetization. The intrinsic causes of anisotropies in these systems are the spin-orbit coupling of the electrons and the long-range magnetic dipole interaction. While the dipole interaction always favors an orientation of magnetization in the plane of the film, spin-orbit coupling can favor different orientations of magnetization on the surface and in the inner layers of the film. This can lead to a competition between anisotropies, which in turn leads to a spin reorientation transition with varying film thickness. This transition can be of varying order, i. e. be continuous or discontinuous. Experiments also find a spin reorientation transition with varying temperature, which until now was not well understood. In the framework of a classical Heisenberg model this transition is investigate d by means of different theoretical methods in the course of this thesis. At zero temperature the system can be dealt with analytically and criteria for the spin reorientation transition and its order are found. Furthermore it is investigated whether the long-range dipole interaction results in a domain ground state. These investigations are extended to finite temperatures by means of a molecular field theory and results are compared to Monte Carlo simulations. It is shown that in contrast to other works the temperature driven spin reorientation transition in the monolayer is discontinuous also in the simulations, whereas in general it is continuous for the bilayer. Consequently the molecular field theory and the Monte Carlo simulations agree qualitatively. Exemplary for thicker films the influence of an external magnetic field is investigated in the bilayer, furthermore the effective anisotropies Kn(T) of the phenomenological Landau theory are calculated numerically for the microscopic model. Analytic expres sions for the dependence of the anisotropies Kn(T) on the parameters of the model are obtained by the means of perturbation theory, which lead to a deeper understanding of the spin reorientation transition. Accordingly to this the origin for the spin reorientation transition lies in the differing temperature dependence of the dipolar and spin-orbit parts of the Kn(T). Additionally the magnetization in the surface of the film decreases more rapidly with increasing temperature. As a consequence the influence of the surface anisotropy decreases with increasing temperature. This effects a similar result as increasing the film thickness and leads to the transition. Finally the model is extended to continuous film thicknesses, since in experiment the spin reorientation transition depends crucially on film thickness. The results of this extended model are compared to experiment and give good agreement. [Text] [View with Perseus links] (0.29)

3. Grundt, Peter; Heck-Reaktion und Carbonylreaktionen - eine leistungsfahige Kombination - Heck reaction and carbonyl reactions - a versatile combination: Prof. Dr. rer.nat. Gerald Dyker, Prof. Dr. Dietrich Dopp; (in German) Die Heck-Reaktion von ungesattigten Alkoholen fuhrt zu Aldehyden oder Ketonen. Diese Art von Heck-Reaktion kann bei Einsatz von ungesattigten Carbonylverbindungen als aromatische Kupplungskomponenten mit klassischen Carbonylreaktionen wie einer Robinson-analogen Anellierung kombiniert werden. Die intermolekulare Version dieses Domino-Prozesses ist ein Zugang zu Phenanthrensystemen. Durch eine intramolekulare Heck-Reaktion als makrozyklisierende Ringschlussreaktion gefolgt von einer Sequenz aus einer Michael- Reaktion und einer Aldol-Kondensation wird ein Steroidgerust erhalten. Aus einfachen Ausgangsmaterialen ist somit eine breite Produktpalette von komplexen Zielmolekulen zuganglich. The Heck reaction with unsaturated alcohols yields aldehydes or ketones. Employing unsaturated carbonyl compounds as coupling components this type of Heck reaction can be combined with classical carbonyl reactions such as a Robinson-type annulation: The intermolecular version of this domino process is an access to phenanthrene systems. Using an intramolecular Heck reaction as a macrocyclic ring closure reaction followed by sequence consisting of a Michael addition and an Aldol condensation a steroid skeleton is obtained. Hence, a wide range of complex target molecules is accessible from simple building blocks. [Text] [View with Perseus links] (0.29)

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5 from Digital Library of the Commons

1. Birner, Regina, Gunaweera, Hasantha; Between Market Failure, Policy Failure and 'Community Failure': Property Rights, Crop-Livestock Conflicts and the Adoption of Sustainable Land Use Practices in the Dry Zone of Sri Lanka: CGIAR System-Wide Program on Property Rights and Collective Action, International Food Policy Research Institute (IFPRI), Washington, DC; (in English) "Using the case of the semi-arid zone of Southern Sri Lanka as an example, the paper shows that crop damages caused by grazing livestock can constitute an important obstacle to the adoption of available technologies for more sustainable land use. The paper considers crop damages as an externality problem and shows that the classical solutions to externalities-- the neo-liberal, the interventionist solution and the communitarian solution-- cannot be applied in the Sri Lankan case due to market failure, government failure and 'community failure.' The paper discusses collective action and bargaining between organized interest groups as an alternative solution and analyses the conditions which make such a solution work. The paper concludes that-- in the Sri Lankan case-- a decentralized system of government, a preferential voting system creating incentives for politicians, an institutionalized negotiation platform, and the facilitating role of intermediaries favored this solution." [Text] [View with Perseus links] (0.31)

2. Dedeurwaerdere, Tom; Ethics and Learning: From State Regulation towards Reflexive Self-Regulation of the Information Society: (in English) "In this presentation we consider an original institutional solution proposed by E. Brousseau, for a hierarchical framing of the self-regulation of the Internet, which tries to encounter the incompleteness of solely technical means of self-regulation (standardisation or juridical self-rule) as well as the inefficiency of co-regulation in a classical sense. We evaluate this type of solution, form the point of view of itns contribution to a process of ethical learning, taking into account the contextual conditions of access to a more reflexive self-regulation of the Internet. In order to do so, we show that it is necessary to modify the procedural approach of reflexivity in the actual attempts to regulate the Internet, through constructing more adequately the conditions of capacitation of the cooperative moment through an incentive politics of inferential nature." [Text] [View with Perseus links] (0.29)

3. Karlsson, Sylvia; Heterogeneity and Harmonization in Layered Institutional Approaches to Global Commons Issues: The Case of Pesticide Use in the South: (in English) "There are an increasing number of environmental issues which demonstrate local-global linkages in both their driving forces and effects, and where policy responses are initiated in institutions at both local, national and global level. This creates opportunities to test the study of such issues from the theoretical mindset of CPR management. The paper argues that the level of multilayered complexity and interdependence that emerging environmental issues exhibit along the three dimensions of culpability, suffering and responsibility make it valid to study them as 'global commons issues' across levels, from the local to the global. This is attempting one additional step to the last year's transfer of theoretical models from local CPRs to global ones, and from classical natural resource CPRs to new types. The study employed the case of pesticide use in the South as a probe into problem structuring and policy making at local, national and global levels and highlights the knowledge, institutions and values that influence decision-making. "On the issue of knowledge the analysis revolves around the globally harmonised vs. locally adapted or produced knowledge. Regarding institutions, the concerns are: where in the complex net of hierarchically nested institutions decisions are made, and which response strategies are available to actors at each level? And regarding values, my focus is on: who or what institution at which levels is assigned culpability for the problem, and who is assigned the responsibility for mitigating action? "Semi-structured qualitative interviews with representatives of stakeholder groups at each level with Kenya and Costa Rica as cases for the national and local level was used as the primary methodological approach, complemented by studying policy relevant documents of each institution. Pesticides were framed as a problem along four basic dimensions; economic/trade, technical, health and environment, with much variation across levels and stakeholder groups. The common denominator across levels was the primacy of economic and trade concerns around pest management on export crops and the virtual absence of concern for the environment, especially the environment in developing countries. In response strategies there were conflicting approaches of stressing local heterogeneity or striving for global harmonisation in knowledge production and policy strategies. "Based on the results I argue that there is a value in harmonisation of knowledge in certain aspects but even more in the level specific adaptation and local knowledge production to make decision-makers able to adjust their response strategies. I argue that there is a need for more unified objectives of policies across levels, with a parallel need for institutional diversity in addressing the risks with pesticide use. And, finally, I argue that there is a need for a more unified understanding of who is suffering, who is behind the driving forces and who in the institutional complex at various levels has the power, capacity and responsibility, to initiate risk reduction. This last point, as well as the whole theoretical approach, has as its underlying assumption that the issue is framed as a global one, ethically and practically." [Text] [View with Perseus links] (0.23)

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6 from Elektronisches Dokumenten-, Archivierungs- und Retrievalsystem der Universit?x00E4;t Dortmund

1. Thiele, Helmut; On Closure Operators in Fuzzy Algebras and Fuzzy Deductive Systems: (in English) The starting point of this paper is the classical wellknown theorem due to G. BIRKHOFF,P.HALL,andJ.SCHMIDT which establishes a one-to-one correspondence between compact closure operators, inductive closure operators, inductive closure systems, and closure operators generated in universal algebras (and generated in deductive systems, respectively). In the paper presented we make first steps in order to generalize this important theorem to the fuzzy set theory and fuzzy algebra (and fuzzy deductive systems, respectively). [Text] [View with Perseus links] (1.66)

2. Deb, Kalyanmoy; Non-linear Goal Programming Using Multi-Objective Genetic Algorithms: (in English) Goal programming is a technique often used in engineering design activities primarily to find a compromised solution which will simultaneously satisfy a number of design goals. In solving goal programming problems, classical methods reduce the multiple goal-attainment problem into a single objective of minimizing a weighted sum of deviations from goals. Moreover, in tackling non-linear goal programming problems, classical methods use successive linearization techniques, which are sensitive to the chosen starting solution. In this paper, we pose the goal programming problem as a multi-objective optimization problem of minimizing deviations from individual goals. This procedure eliminates the need of having extra constraints needed with classical formulations and also eliminates the need of any user-defined weight factor for each goal. The proposed technique can also solve goal programming problems having nonconvex trade-off region, which are difficult to solve using classical methods. The efficacy of the proposed method is demonstrated by solving a number of non-linear test problems and by solving an engineering design problem. The results suggest that the proposed approach is an unique, effective, and most practical tool for solving goal programming problems. [Text] [View with Perseus links] (1.21)

3. Beyer, Hans-Georg; Noisy Optimization with Evolution Strategies: (in English) Evolution strategies are general, nature-inspired heuristics for search and optimization. Supported both by empirical evidence and by recent theoretical findings, there is a common belief that evolution strategies are robust and reliable, and frequently they are the method of choice if neither derivatives of the objective function are at hand nor differentiability and numerical accuracy can be assumed. However, despite their widespread use, there is little exchange between members of the classical optimization community and people working in the field of evolutionary computation. It is our belief that both sides would benefit from such an exchange. In this paper, we present a brief outline of evolution strategies and discuss some of their properties in the presence of noise. We then empirically demonstrate that for a simple but nonetheless nontrivial noisy objective function, an evolution strategy outperforms other optimization algorithms designed to be able to cope with noise. The environment in which the algorithms are tested is deliberately chosen to afford a transparency of the results that reveals the strengths and shortcomings of the strategies, making it possible to draw conclusions with regard to the design of better optimization algorithms for noisy environments. [Text] [View with Perseus links] (0.80)

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3 from Ethnologue: Languages of the World

1. QUECHUA, CLASSICAL: an extinct language of Peru: A page from the Web edition of the Ethnologue giving basic facts about the language and where it is spoken. [Text] [View with Perseus links] (1.74)

2. NAHUATL, CLASSICAL: an extinct language of Mexico: A page from the Web edition of the Ethnologue giving basic facts about the language and where it is spoken. [Text] [View with Perseus links] (1.60)

3. MANDAIC, CLASSICAL: an extinct language of Iran: A page from the Web edition of the Ethnologue giving basic facts about the language and where it is spoken. [Text] [View with Perseus links] (1.52)

1 from Formations

1. Tseelon, Efrat; Woman and the Gaze: 'Is the gaze of cultural representation male?' one may ask, rephrasing the title of Ann Kaplan's 1983 article. She posits the question against a backdrop of feminist literature based on the comfortable binary assumption of a male voyeur and a female object of vision. Binary notions, even in the academy, have an irresistible appeal. And they certainly prove a popular currency in the culture at large. Time and again they survive critical attempts to deconstruct, problematise, or destabilise them. The present essay is one such attempt at rethinking woman and the gaze. Using a psychoanalytic position as an analytical tool for deconstructing the patriarchal gaze, gaze theory developed an orthodoxy of a gendered gaze which is eroticising and controlling. It was sparked off by Laura Mulvey's early work which advanced the notion that the cinematic gaze is male, on account of the feminine image it constructs, and the mode of pleasure it offers the female viewer. Initially based on analyses of classical Hollywood cinema, the assumptions of gaze theory have been essentialised paradigmatically to all cinema. Assuming a totalising voice that speaks for the category of 'woman' and 'man', and a unitary 'subject', gaze theory theorised all desire as heterosexual male, and woman as just an object devoid of a spectatorial position, except in drag. In recent years, such a monolithic, homogenising and heterosexual model of spectatorship came under attack. The paper explores the consequences of this re-thinking, especially in relation to the exemplary films of Almodovar. [Text] [View with Perseus links] (0.24)

4 from Fourth International Symposium on Cavitation

1. Berchiche, Nabila, Franc, Jean-Pierre, Michel, Jean-Marie; A Cavitation Erosion Model for Ductile Materials: An analytical model is proposed for the prediction of cavitation erosion of ductile materials. It is based upon a physical analysis of the work-hardening process due to the successive bubble collapses. The material is characterized by its classical stress-strain relationship and its metallurgical behaviour is analysed from microhardness measurements on cross sections of eroded samples. The flow aggressiveness is determined from pitting tests, using the material properties to go back to the impact loads. The histogram of impact loads is applied numerically a large number of times on the material surface and the evolution of the mass loss with the exposure time is computed. The approach is supported by experimental tests. [Text] [View with Perseus links] (0.35)

2. Han, Jae-Moon, Kong, Do-Sung, Song, In-Haeng, Lee, Chang-Sup; Analysis of the Cavitating Flow Around the Horn-type Rudder in the Race of a Propeller: This paper describes numerical methods by a mixed formulation of the boundary value problem (BVP) for the prediction of the cavitating flow around the horn-type rudder working behind a propeller. The blade BVP is treated by the classical vortex lattice method, whereas the rudder BVP is solved by the surface panel method. The three-dimensional flow around the rudder and the propeller is computed simultaneously, considering the interactions between them. A modified kinematic boundary condition is applied to predict the mean velocity and flow volume through gap flow region of the horn-type rudder. To validate the numerical scheme, an experiment is performed in large cavitation tunnel. The surface pressure distributions and cavity patterns on the horn-type rudder are investigated and compared with computational results, showing good agreement with measured results. [Text] [View with Perseus links] (0.34)

3. Rapposelli, Emilio, d'Agostino, Luca; A Modified Isenthalpic Model of Cavitation in Plane Journal Bearings: This paper presents the development of a quasi-homogeneous isenthalpic cavitation flow model, suitably modified to account for thermal cavitation, and its application to the study of plane journal bearings with constant eccentricity. The proposed model treats the cavitating and noncavitating portions of the fluid in a unified manner with the aim of avoiding the use of matching conditions at the phase interface, whose accuracy is questionable in the presence of significant inertial and/or unsteady effects. A non-linear analysis which accounts for the inertia of the lubricant is used to determine the reaction forces caused by the shaft eccentricity both in the viscosity-dominated regime and at intermediate values of the Reynolds number, where the inertia of the lubricant is no longer negligible. The classical iteration method for the Reynolds lubrication equation (Muster and Sternlicht, 1965; Mori and Mori, 1991; Reinhardt and Lund, 1975) has been extended to the two-phase flow case in order to account for flow acceleration effects in the presence of cavitation. Comparison with available experimental data are shown in a number of representative cases, in order to illustrate the validity and the capabilities of the proposed model for the analysis of cavitating flows in journal bearings, in view of its extension to the case of whirling loads and eccentricities [Text] [View with Perseus links] (0.30)

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1 from Hofstra University EPrint Archive

1. Bhargava, Manjul; The fifteen theorem, and generalizations: The classical "Four Squares Theorem" of Lagrange asserts that any positive integer can be expressed as the sum of four squares; that is, the quadratic form a² + b² + c² + d² represents all (positive) integers. When does a general quadratic form represent all integers? When does it represent all odd integers? When does it represent all primes? We show how all these questions turn out to have very simple and surprising answers. <p> This paper was given at the Robert J. Bumcrot Festschrift on May 11, 2001. [Text] [View with Perseus links] (0.43)

5 from Hong Kong University Theses Online

1. Ho, Yuen-ying; The effect of introducing a computer software in enhancing comprehension of classical Chinese text [Text] [View with Perseus links] (1.36)

2. Chong Ka-wong; Improved algorithms for some classical graph problems [Text] [View with Perseus links] (1.19)

3. Lam, Lap; A study of Yu Dafu's (1896-1945) classical Chinese poetry???????? [Text] [View with Perseus links] (1.15)

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18 from Humboldt University of Berlin, GERMANY, Document Server

1. Muller, Uwe; Umfassende klassische Analyse des geeichten SL(2,R)-U(1)-Wess-Zumino-Novikov-Witten-Modells: (in German) Abstract In recent years, Black Holes have attracted much attention, in particular, because of their unusual quantum-theoretical properties. An interesting model, in this context, is the SL(2,R)/U(1) gauged Wess-Zumino-Novikov-Witten model, which can be interpreted stringtheoretically as Euclidean two-dimensional Black Hole. The present dissertation analyzes the classical properties of this model, in order to prepare the basis for quantum-theoretical investigations. First, gauged Wess-Zumino-Novikov-Witten (WZNW) models are intoduced in general. Usually, they are formulated including gauge fields, whose equations of motion are purely algebraic. In the present dissertation, the gauge fields are eliminated from the models. A class of non-linear integrable field theories arises, whose equations of motion can be represented by Lax pairs explicitly. These results are specialized to the SL(2,R)/U(1) gauged WZNW model. For comparison, the elimination of the gauge field by explicit path integration is also investigated. But due to mathematical ambiguities, this investigation does not lead to a final result. The classical SL(2,R)/U(1) gauged WZNW model is investigated in an infinitely extended Minkowski space-time as well as with spatially periodic boundary conditions. The latter is important for the stringtheoretical interpretation of the model. The non-linear equations of motion and their general solution are given. A procedure is derived to determine the parameter functions of the general solution from given initial conditions of the equations of motion. By means of this procedure the Poisson brackets of the parameter functions are calculated from the canonical Poisson brackets of the physical fields. It is shown that there is a non-local canonical transformation of the non-linear physical fields onto free fields. The corresponding Backlund transformation is presented. [Text] [View with Perseus links] (0.39)

2. Altevogt, Torsten; Der optische Start-Effekt mit quantisiertem Strahlungsfeld: (in German) The theoretical description of spectroscopic experiments usu ally relies on a semiclassical approach where the matter system is described in terms of quantum mechanics while the radiation field is treated classically. This approach does n ot work well for systems with a strong coupling between the matter system and photons of the radiation field. The latter can be the case within an optical resonator.In this thesis, additional effects of a quantized radiation field are inves tigated on a pump-probe experiment for detecting the optical Stark effect. One significant effect is that the lineshape of the shifted resonance displays the photon statistics of the pump field. For small pump detuning probe gain results in a frequency regime where the semiclassical treatment predicts absorption. This effect is refered to nonclassical gain. For larger ensembles of two-level systems, additional substructures and resonances appear within the probe absorption spectrum. Also non- diagonal elements of the field density matrix can be detected in such an experiment. In order to describe a more complex matter systems, the optical Stark effect has been treated in terms of a density matrix approach with quantized radiation fields. For a quantitative description of nonclassical gain, higher correlation terms had to be treated properly. Moreover, conserved quantities were taken into account in approximate decouplings. The density matrix approach was applied to the description of the optical Stark effect on impurity-bound excitons in semiconductors. These systems are of high interest as their narrow resonances might allow the demonstration of fine effects of the quantized radiation field. [Text] [View with Perseus links] (0.31)

3. Helling, Robert; Scattering in supersymmetric M(atrix) models: (in English) In this thesis, we present several tests of the M(atrix)-Model conjecture that asserts that the dynamics of M-Theory, the eleven-dimensional Ur-theory containing all known string theories and also eleven-dimensional supergravity in specific limits, is given by a quantum mechanical matrix model. In particular, scattering processes are analyzed both from the M(atrix)-Model and from the supergravity perspective and the corresponding S-matrix elements are compared. We find impressive agreement between these two theories as long as only classical supergravity is considered. If one includes also quantum effects on the supergravity side, the agreement does not persist. In addition to these calculations, the question of the existence of classical solutions to the M(atrix)-Model equations of motion with momentum transfer is addressed and answered negatively. [Text] [View with Perseus links] (0.30)

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2 from Ibiblio Collection Index

1. Nassar, Nassib; Nassib Nassar (pianist): Nassar, Nassib; Recordings of classical pianist, Nassib Nassar. [Text] (0.64)

2. Mutopia: Gray, Andrew; An extensive archive of freely downloadable music and musical transcriptions in the categories of: Early Mediaeval, Renaissance, Baroque, Classical, Romantic, Modern, Jazz, and Hymn. [Text] (0.62)

71 from Institut National de Physique Nucleaire et de Physique des Particules

1. Bohigas O., Giannoni M.J., Schmit C.; Spectral fluctuations of classically chaotic quantum systems [Text] (1.66)

2. Schmit C.; Quantum and classical properties of some billiards on the hyperbolic plane [Text] (1.61)

3. Beraud R.; Introduction to classical IGISOL [Text] (1.57)

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3 from LSU Electronic Thesis and Dissertation Archive

1. Broadwater, Kimberly Jaye; The Effects of Singing on Blood Pressure in Classically Trained Singers: (in English) Blood pressure readings were taken in four normotensive, classically trained singers of varying age and experience. The results show changes during the systolic and diastolic phases of blood pressure measurements while singing. While systolic blood pressure changes were individualized and random, diastolic blood pressure changes generally showed a direct correlation to changes in intrathoracic pressure. Additional research using a larger subject base involving normotensive, hypertensive, and hypotensive populations is warranted [Text] [View with Perseus links] (0.43)

2. Aliyu, Mohammad Dikko; A Factorization Approach for Solving the Hamilton-Jacobi Equations in Nonlinear Optimal Control: (in English) The Hamilton-Jacobi equation (HJE) arose early in the last century in the study of the calculus of variation, classical mechanics and Hamiltonian systems. Recently, there has been a renewed interest in HJEs arising in various analysis and synthesis problems in systems theory. The HJE despite providing a necessary and sufficient condition for an optimal control, is very difficult to solve for general nonlinear systems, and therefore its application remained limited to linear systems. Yet, the HJE has been studied extensively in the literature from diverse areas of science and engineering, varying from mathematical physics, to mechanics, control theory, and to partial differential equations. In this thesis, some analytical approaches for solving the HJEs arising in H-infinity, mixed H2/H-infinity and H2 control problems for nonlinear systems are developed. Two major approaches are presented. The first approach is essentially an inversion or factorization method, and involves solving the HJE like a scalar quadratic algebraic equation with the gradient of the smooth scalar function as unknown. Since the HJE is a quadratic equation in the gradient of the unknown scalar function, we obtain two parameterized solutions which represent a parameterization of all solutions to the HJE. Thus, the problem is reduced to that of factorization of a scalar algebraic equation which we call the {it discriminant equation} (or inequality). The main difficulties with this approach however are: (i) even after obtaining a solution to the discriminant equation, there is no guarantee that the gradient vector obtained subsequently represents a scalar function (i.e. represents a symmetric solution to the HJE); and (ii) there is no guarantee that the resulting solution is positive-definite. However, these difficulties can still be overcome by some additional constraints to the problem. Computational procedures for determining symmetric elementary solutions are then presented. The second apporoach involves converting the first-order HJ partial differential equation (PDE) to a second-order PDE. Then using a suitable parameterization, this second-order PDE is converted to a coupled system of higher-order nonlinear PDEs which can be solved using some available SYMBOLIC manipulation packages or by other methods. In general, there are no systematic procedures for solving the resulting system of higher-order PDEs, but various ad-hoc procedures can be used. This presents the most serious limitations of the approach. Both the time-varying and time-invariant systems are considered. [Text] [View with Perseus links] (0.26)

3. Armstrong IV, William Hamilton; Neo-Onnagata: Professional Cross-Dressed Actors and Their Roles on the Contemporary Japanese Stage: (in English) Neo-Onnagata: Professional Cross-dressed Actors and Their Roles on the Contemporary Japanese Stage explores the representation of male and female gender in the contemporary Japanese theatre. I particularly discuss a specialized subset of Japanese actor: the neo-onnagata, a contemporary theatre counterpart to Japans highly stylized classical kabuki tradition of cross-dressed representation. This dissertation represents my attempt to provide these basic aims: to situate the contemporary Japanese cross-dresser in Japanese tradition, to show how cross-dressing acts as a sharp social commentary and mirror, and to introduce some little-represented cross-dressing actors of the contemporary Japanese stage to the academic community at large. In addition, I examine the conservative gender role system of Japan and demonstrate how the neo-onnagata challenge traditional performance and sex roles. Particularly, I seek to showcase neo-onnagata as expanding opportunities for male actors and as new gendered models for men. [Text] [View with Perseus links] (0.15)

15 from Library of Congress Open Archive Initiative Repository 1

1. Select classical & mathematical seminary.; Mr. Anderson and family are respectfully invited to attend the fifth annual exhibition of the select classical & mathematical seminary, on Friday, July 30, in the Apollo Hall, on Pennsylvania Avenue, exercises to commence at 4.5 o' clock, P. M. [Washington, D. C. n. d.].: (in English) Mr. Anderson supplied with pen., Printed Ephemera Collection; Portfolio 210, Folder 21., Page Order: Leaflet [Text] [View with Perseus links] (2.51)

2. Maylath, Henry.; Aux Bords du Gange (Classical pianist) / [Text] [View with Perseus links] (1.85)

3. Maylath, Henry.; Berceuse (Classical pianist) / [Text] [View with Perseus links] (1.48)

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319 from NCSTRL Historical Collection

1. Henzinger, Thomas A., Raskin, Jean-Francois, Schobbens, Pierre-Yves; Temporal Logics, Automata, and Classical Theories for DefiningReal-Time Languages: A specification formalism for reactive systems defines a class of omega-languages. We call a specification formalism fully decidable if it is constructively closed under boolean operations and has a decidable satisfiability (nonemptiness) problem. There are two important, robust classes of omega-languages that are definable by fully decidable formalisms. The omega-regular languages are definable by finite automata, or equivalently, by the Sequential Calculus. The counter-free omega-regular languages are definable by temporal logic, or equivalently, by the first-order fragment of the Sequential Calculus. The gap between both classes can be closed by finite counting (using automata connectives), or equivalently, by projection (existential second-order quantification over letters). A specification formalism for real-time systems defines a class of timed omega-languages, whose letters have real-numbered time stamps. Two popular ways of specifying timing constraints rely on the use of clocks, and on the use of time bounds for temporal operators. However, temporal logics with clocks or time bounds have undecidable satisfiability problems, and finite automata with clocks (so-called timed automata are not closed under complement. Therefore, two fully decidable restrictions of these formalisms have been proposed. In the first case, clocks are restricted to event clocks, which measure distances to immediately preceding or succeeding events only. In the second case, time bounds are restricted to nonsingular intervals, which cannot specify the exact punctuality of events. We show that the resulting classes of timed omega-languages are robust, and we explain their relationship. First, we show that temporal logic with event clocks defines the same class of timed omega-languages as temporal logic with nonsingular time bounds, and we identify a first-order monadic theory that also defines this class. Second, we show that if the ability of finite counting is added to these formalisms, we obtain the class of timed omega-languages that are definable by finite automata with event clocks, or equivalently, by a restricted second-order extension of the monadic theory. Third, we show that if projection is added, we obtain the class of timed omega-languages that are definable by timed automata, or equivalently, by the full second-order extension of the monadic theory. These results identify three robust classes of timed omega-languages, of which the third, while popular, is not definable by a fully decidable formalism. By contrast, the first two classes are definable by fully decidable formalisms from temporal logic, from automata theory, and from monadic logic. Since the gap between these two classes can be closed by finite counting, we dub them the timed omega-regular languages and the timed counter-free omega-regular languages, respectively. [Text] (5.19)

2. Wolter, Frank, Zakharyaschev, Michael; Intuitionistic Modal Logics as fragments of Classical Bimodal Logics: Godel's translation of intuitionistic formulas into modal ones provides the well-known embedding of intermediate logics into extensions of Lewis' system S4, which reflects and sometimes preserves such properties as decidability, Kripke completeness, the finite model property. In this paper we establish a similar relationship between intuitionistic modal logics and classical bimodal logics. We also obtain some general results on the finite model property of intuitionistic modal logics first by proving them for bimodal logics and then using the preservation theorem. [Text] [View with Perseus links] (2.73)

3. Kalathil, Biju Joseph; Supporting local autonomy in a distributed object-oriented database: Local autonomy of the individual databases in a distributed system is important as administrators of the individual databases often need to have complete control over how their data are structured, used and managed. Classical distributed databases support distribution transparency, replication transparency and fragmentation transparency. Researchers have recognized that transparent access to databases in a distributed system is inherently incompatible with the notions of local autonomy. In this thesis we propose a new model of distributed object-oriented databases that supports local autonomy of the individual databases. Local autonomy is achieved by allowing the database administrators of the individual databases to adapt a globally available schema to fit their local needs, but still be able to share data with others in the distributed system. Central to this model is a new concept called federated collections, which are collections of objects of the same class that may be distributed across a number of databases in one or more sites. The schema of a federated collection (FC) is available globally in the form of the version trees of the classes that constitute the schema. The schema of an FC includes the class of the member objects (member class) of the FC, and transitively all the classes used directly or indirectly in the definition of the member class. The administrator of each database that participates in a federated collection may create a new version of a globally available class and adopt it for the local component of a federated collection. Class version mapping and federated queries support seamless querying of federated collections. [Text] [View with Perseus links] (2.43)

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1 from NSDL Test Collection

1. Classical Physics [Reference article in LEVEL5 Astronomical Glossary] (2.66)

2 from Nottingham ePrints

1. Barrett, John W.; The classical evaluation of relativistic spin networks: The evaluation of a relativistic spin network for the classical case of the Lie group SU(2) is given by an integral formula over copies of SU(2). For the graph determined by a 4-simplex this gives the evaluation as an integral over a space of geometries for a 4-simplex. [Text] [View with Perseus links] (1.08)

2. Baez, John C., Barrett, John W.; The Quantum Tetrahedron in 3 and 4 Dimensions: Recent work on state sum models of quantum gravity in 3 and 4 dimensions has led to interest in the quantum tetrahedron'. Starting with a classical phase space whose points correspond to geometries of the tetrahedron in R^3, we use geometric quantization to obtain a Hilbert space of states. This Hilbert space has a basis of states labeled by the areas of the faces of the tetrahedron together with one more quantum number, e.g. the area of one of the parallelograms formed by midpoints of the tetrahedron's edges. Repeating the procedure for the tetrahedron in R^4, we obtain a Hilbert space with a basis labelled solely by the areas of the tetrahedron's faces. An analysis of this result yields a geometrical explanation of the otherwise puzzling fact that the quantum tetrahedron has more degrees of freedom in 3 dimensions than in 4 dimensions. [Text] [View with Perseus links] (0.45)

166 from OCLC Online Computer Library Center Theses and Dissertations Repository

1. Ogilvy, J. D. A.--(Jack David Angus),--1903-; Books known to Anglo-Latin writers from Aldhelm to Alcuin (670-804)--[by] J. D. A. Ogilvy.: "Lithoprinted.", "A Harvard doctoral thesis [1933]...[revised] for publication." - Introd., Table of abbreviations (p.vii-viii)- Bibliography (p. ix-xvi) -Introduction.- Catalogue of books known to Anglo-Latin writers from Aldhelm to Alcuin.- The chief sources of information employed by writers of the period (p. 91-92).- Growth of English libraries.- Conclusion.- Appendices: A. Provenance and form of English books. B. Notes on English education. C. English books on the continent. [Text] (2.54)

2. Cornelia, William Barnabas,--1885-; The classical sources of the nature references in Ronsard's poetry,--by William B. Cornelia.: Issued also as thesis (Ph. D.) Columbia University., Bibliography: p. 221-226. [Text] (2.47)

3. Carter, Christine Louise., Washington University (Saint Louis, Mo.).--Theses.--Classics.; A study of select Hadrianic coins in the Wulfing Collection /--by Christine Louise Carter: Thesis (A.M.)--Washington University, 1976. Dept. of Classics., Includes bibliography. [Text] (2.09)

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2 from Objects under development

1. Hentschel, Martina; Mesoscopic wave phenomena in electronic and optical ring structures, alternative/translated: Mesoskopische Wellenphanomene in elektronischen und optischen Ringstrukturen: TU Dresden, Mathematik und Naturwissenschaften, Physik, Max-Planck-Institut fur Physik komplexer Systeme; (in English) In this work we investigate wave phenomena in mesoscopic systems using different theoretical approaches. In Part I, we focus on effectively one-dimensional electronic ring structures and address the phenomenon of geometric phases in spin-dependent electronic transport in the presence of non-uniform magnetic fields. In the general non-adiabatic case, exact solutions of the Schrodinger equation are used in a transfer matrix formalism to compute the transmission probability through the ring. In the magneto-conductance we identify clear signatures of interference effects due to geometric phases, for example in rings where the non-uniform field is created by a central micromagnet. For the special case of an in-plane magnetic field we predict an interesting spin-flip effect that allows one to control the spin polarization of electrons by applying an external Aharonov-Bohm flux. Optical mesoscopic systems are the subject of Part II. We consider two-dimensional annular structures characterized by different refractive indices, and apply classical methods from geometric optics as well as wave concepts based on Maxwell's equations. For the first time, an S-matrix approach is successfully employed in the description of resonances in optical microresonators; in particular we propose the dielectric annular billiard as an attractive model system. Comparing ray and wave pictures, we find general agreement, except for large wavelengths of the order of the system size, where corrections to the ray model are necessary. The Goos-Hanchen effect as an extension of the ray picture is shown to quantitatively account for wave modifications of Fresnel's laws due to curved interfaces. We derive novel analytical expressions for the corrected Fresnel formulas for both polarizations of light. Motivated by the successful ray description, we give a conclusive interpretation of a recent filter experiment on a quadrupolar glass fibre, and suggest novel concepts for microresonator-based lasers., Gegenstand dieser Arbeit sind Wellenphanomene in mesoskopischen Ringstrukturen. In Teil I der Arbeit befassen wir uns mit spinabhangigem Transport von Elektronen in effektiv eindimensionalen Ringen in Gegenwart inhomogener Magnetfelder. Wir benutzen die exakten Losungen der Schrodinger-Gleichung im allgemeinen nicht-adiabatischen Fall in einem Transfer-Matrix-Formalismus und untersuchen Auswirkungen von geometrischen Phasen auf den Magnetwiderstand. Fur den Spezialfall eines Magnetfeldes in der Ringebene sagen wir einen interessanten Spin-Flip-Effekt vorher, der die Steuerung der Polarisationsrichtung von Elektronen uber einen externen Aharonov-Bohm-Fluss erlaubt. Optische mesoskopische Systeme sind Thema von Teil II dieser Arbeit. Wir betrachten zweidimensionale annulare Strukturen, charakterisiert durch unterschiedliche Brechungsindizes, sowohl im klassischen Bild der geometrischen Optik als auch mit Wellenmethoden auf der Grundlage der Maxwellschen Gleichungen. Insbesondere diskutieren wir erstmals eine Streumatrixbeschreibung optischer Mikroresonatoren und wenden sie auf das dielektrische annulare Billard an. Ein Vergleich der Ergebnisse des Wellen- und Strahlenbildes liefert eine gute Ubereinstimmung, jedoch sind im Grenzfall grosser Wellenlangen von der Ordnung der Systemabmessungen Korrekturen zum Strahlenbild notig. Wir zeigen am Beispiel von Fresnel-Gesetzen fur gekrummte Oberflachen erstmals, dass der Goos-Hanchen-Effekt diese Korrekturen quantitativ erfasst. Ausgehend von der Wellenbeschreibung leiten wir neue analytische Formeln fur verallgemeinerte Fresnel-Gesetze fur beide moglichen Polarisationsrichtungen ab. Die Anwendung des Strahlenbildes erlaubt eine schlussige Interpretation eines Experiments mit einer quadrupolaren Glasfaser, ausserdem schlagen wir Strahlenkonzepte als Grundlage der Konstruktion von Mikrolasern mit massgeschneiderten Charakteristika vor. [Text] (0.09)

2. Binder, Jorg Dipl.-Phys.; Giant Magnetoresistance - eine ab-initio Beschreibung, alternative/translated: Giant Magnetoresistance - an ab-initio description: Technische Universitat Dresden, Mathematik und Naturwissenschaften, Physik, Institut fur Theoretische Physik; (in German) Die vorliegende Arbeit ist ein Beitrag zur Theorie des spinabhangigen Transports in magnetischen Vielfachschichten. Es wird erstmalig eine parameterfreie Beschreibung des Giant Magnetoresistance (GMR) vorgelegt, welche detaillierte Einsichten in die mikroskopischen Vorgange gestattet. Die ab-initio Berechnung der Elektronenstruktur der magnetischen Vielfachschichten basiert auf der Spindichtefunktionaltheorie unter Verwendung eines Screened Korringa-Kohn-Rostoker-Verfahrens. Die Streueigenschaften von Punktdefekten werden uber die Greensche Funktion des gestorten Systems selbstkonsistent bestimmt. Die Transporteigenschaften werden durch Losung der quasiklassischen Boltzmann-Gleichung unter Berucksichtigung der Elektronenstruktur der Vielfachschicht und der Anisotropie der Streuung an Fremdatomen berechnet. Die Boltzmann-Gleichung wird iterativ unter Einbeziehung der Vertex-Korrekturen gelost. Der Formalismus wird auf Co/Cu- und Fe/Cr-Vielfachschichten, die Standardsysteme der Magnetoelektronik, angewandt. Es werden die Abhangigkeit der Streuquerschnitte, der spezifischen Restwiderstande und des GMR von der Art und der Lage der Ubergangsmetalldefekte in Co/Cu- und Fe/Cr-Vielfachschichten diskutiert. Daruber hinaus wird der Einfluss des Quantum Confinements auf den GMR eingehend untersucht. Vorteile und Grenzen der vorliegenden theoretischen Beschreibung werden aufgezeigt., A new theoretical concept to study the microscopic origin of Giant Magnetoresistance (GMR) from first principles is presented. The method is based on ab-initio electronic structure calculations within the spin density functional theory using a Screened Korringa-Kohn-Rostoker method. Scattering at impurity atoms in the multilayers is described by means of a Green's-function method. The scattering potentials are calculated self-consistently. The transport properties are treated quasi-classically solving the Boltzmann equation including the electronic structure of the layered system and the anisotropic scattering. The solution of the Boltzmann equation is performed iteratively taking into account both scattering out and scattering in terms (vertex corrections). The method is applied to Co/Cu and Fe/Cr multilayers. Trends of scattering cross sections, residual resistivities and GMR ratios are discussed for various transition metal impurities at different positions in the Co/Cu or Fe/Cr multilayers. Furthermore the relation between spin dependence of the electronic structure and GMR as well as the role of quantum confinement effects for GMR are investigated. Advantages and limits of the approach are discussed in detail. [Text] (0.08)

3 from PhysNet, Oldenburg, Germany, Document Server

1. P.N. Dowling, C.J. Lennard, B. Turett, turett@oakland.edu; The Fixed Point Property for Subsets of Some Classical Banach Spaces: (in English) [Text] (0.95)

2. Yurii A. Neretin, neretin@main.mccme.rssi.ru; Hua Type Integrals over Unitary Groups and over Projective Limits of: (in English) [Text] (0.78)

3. rojkovsk@math.upenn.edu,; Family Algebras of Representations with Simple Spectrum: (in English) [Text] (0.76)

2 from RIACS - Research Institute for Advanced Computer Science - Eprint Archive

1. Polifke, W., Muller, B., Yee, H.C.; Sound Emission of Rotor Induced Deformations of Generator Casings: The casing of large electrical generators can be deformed slightly by the rotor's magnetic field. The sound emission produced by these periodic deformations, which could possibly exceed guaranteed noise emission limits, is analyzed analytically and numerically. From the deformation of the casing, the normal velocity of the generator's surface is computed. Taking into account the corresponding symmetry, an analytical solution for the acoustic pressure outside the generator is found in terms of the Hankel function of second order. The normal velocity of the generator surface provides the required boundary condition for the acoustic pressure and determines the magnitude of pressure oscillations. For the numerical simulation, the nonlinear 2D Euler equations are formulated in a perturbation form for low Mach number Computational Aeroacoustics (CAA). The spatial derivatives are discretized by the classical sixth-order central interior scheme and a third-order boundary scheme. Spurious high frequency oscillations are damped by a characteristic-based artificial compression method (ACM) filter. The time derivatives are approximated by the classical 4th-order Runge-Kutta method. The numerical results are in excellent agreement with the analytical solution. [Text] [View with Perseus links] (0.67)

2. Yee, H.C., Sjogreen, B.; Designing Adaptive Low-Dissipative High Order Schemes for Long-Time Integrations: A general framework for the design of adaptive low-dissipative high order schemes is presented. It encompasses a rather complete treatment of the numerical approach based on four integrated design criteria: (1) For stability considerations, condition the governing equations before the application of the appropriate numerical scheme whenever it is possible. (2) For consistency, compatible schemes that possess stability properties, including physical and numerical boundary condition treatments, similar to those of the discrete analogue of the continuum are preferred. (3) For the minimization of numerical dissipation contamination, efficient and adaptive numerical dissipation control to further improve nonlinear stability and accuracy should be used. (4) For practical considerations, the numerical approach should be efficient and applicable to general geometries, and an efficient and reliable dynamic grid adaptation should be used if necessary. These design criteria are, in general, very useful to a wide spectrum of flow simulations. However, the demand on the overall numerical approach for nonlinear stability and accuracy is much more stringent for long-time integration of complex multiscale viscous shock/shear/turbulence/acoustics interactions and numerical combustion. Robust classical numerical methods for less complex flow physics are not suitable or practical for such applications. The present approach is designed expressly to address such flow problems, especially unsteady flows. The minimization of employing very fine grids to overcome the production of spurious numerical solutions and/or instability due to under-resolved grids is also sought. The incremental studies to illustrate the performance of the approach are summarized. Extensive testing and full implementation of the approach is forthcoming. The results shown so far are very encouraging. [Text] [View with Perseus links] (0.53)

5 from State and University Library Bremen

1. Kuehn, V.; Turbo-Codes and Turbo-Coded Modulation in CDMA Mobile Radio Systems for Short Frame Transmission: For the last four years, binary parallel concatenated recursive convolutional codes termed Turbo-Codes received great attention due to their amazing error correcting capabilities. Nevertheless, reaching near Shannon limit performance is only possible with a very large interleaver size preventing an application for speech-transmission. This paper presents simulation results for a short-frame data transmission system based on DS-CDMA (Direct-Sequence Code Division Multiple Access) employing Turbo-Codes. As a result, it is shown that Turbo-Codes are no longer superior to classical convolutional codes if the same decoding costs are assumed. [...] [Text] (1.19)

2. Feng, M., Kammeyer, K.D.; Application of Source Separation Algorithms for Mobile Communication Environments: In the most source separation algorithms the classical narrow band data model is used, where only memoryless transmission channels are considered. In the mobile communication environment we have to deal with multipath transmission channels due to the reflections of wavefronts. In order to apply existing source separation algorithms for mobile communication signals, certain modifications of the classical narrow band data model have to be done. In this paper a modification of the data model using OFDM-technique is presented. Using the OFDM-technique the assumption of narrow band signals (needed for the most source separation algorithms) is met automatically. A source separation algorithm named SSARS (Source Separation Algorithm with Reference System) will be considered [...] [Text] (0.73)

3. Pleteit, Hermann; Analyse und Modellierung der Keyhole-Dynamik beim Laserstrahlschweissen von Aluminiumlegierungen: (in German) The subject of this thesis is the behaviour of the keyhole in the laser welding process. In deep penetration laser welding there exists a complex system of weld pool, keyhole, and solid material under the influence of the laser beam. The dynamics which are regarded are primarily the changes in the shape of the keyhole. The dynamics determine the intensity in radiation of the plasma plume which exists above the keyhole. The first part of this thesis focuses on the analysis of time series which contain the experimentally recorded radiation intensity. Since classical techniques like simple Fournier transformation don crucial results, these time series are analysed with methods arising from the theory of nonlinear dynamics. The methods include singular value decomposition, the calculation of correlation sums, and the test of determinism in the origin of the time series by use of surrogate data. The results of this analysis shall give valuable information for the modelling of the keyhole dynamics. The content of the second part is the development of a model for keyhole dynamics from first principles. Several basic assumptions for the physical properties of the weld pool and the keyhole wall lead to a system of nonlinear differential equations. The numerical integration of the model system shows non-trivial behaviour in a wide range of the parameter space. The existence of an attractor, which consists of a complex periodic orbit, dominates the phase space. The model presented here can reproduce qualitatively some aspects of the real laser welding process such as the sensitive dependence of the weld process on the laser power. [Text] (0.22)

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2 from Technical University of Chemnitz - MONARCH

1. T. Penzl; A cyclic low rank Smith method for large, sparse Lyapunov equations with applications in model reduction and optimal control: (in English) We present a new method for the computation of low rank approximations to the solution of large, sparse, stable Lyapunov equations. It is based on a generalization of the classical Smith method and profits by the usual low rank property of the right hand side matrix. The requirements of the method are moderate with respect to both computational cost and memory. Hence, it provides a possibility to tackle large scale control problems. Besides the efficient solution of the matrix equation itself, a thorough integration of the method into several control algorithms can improve their performance to a high degree. This is demonstrated for algorithms for model reduction and optimal control. Furthermore, we propose a heuristic for determining a set of suboptimal ADI shift parameters. This heuristic, which is based on a pair of Arnoldi processes, does not require any a priori knowledge on the spectrum of the coefficient matrix of the Lyapunov equation. Numerical experiments show the efficiency of the iterative scheme combined with the heuristic for the ADI parameters. [Text] [View with Perseus links] (0.33)

2. L. Jentsch, D. Natroshvili, I. Sigua; Mixed Interface Problems of Thermoelastic Pseudo-Oscillations: (in English) Three-dimensional basic and mixed interface problems of the mathematical theory of thermoelastic pseudo-oscillations are considered for piecewise homogeneous anisotropic bodies. Applying the method of boundary potentials and the theory of pseudodifferential equations existence and uniqueness theorems of solutions are proved in the space of regular functions C^(k+ alpha) and in the Bessel-potential (H^(s)_(p)) and Besov (B^(s)_(p,q)) spaces. In addition to the classical regularity results for solutions to the basic interface problems, it is shown that in the mixed interface problems the displacement vector and the temperature are Holder continuous with exponent 0<alpha<1/2. [Text] [View with Perseus links] (0.23)

1 from The American Numismatic Society

1. Bronze medal (2000.25.1): Obverse: classical ruins, Reverse: classical ruins, figure in front [Text] [View with Perseus links] (2.06)

1 from The Eberhard Karls University of Tuebingen

1. Unanue, Emil; ... , Classical vesicular ... : What have we learned on why APC select peptides: Molecular Mechanisms of Antigen Processing, Antigen processing; Peptide displayed by Class II MHC; I-A; C3G7; Peptides selected by I-A g7; Hen egg white Lisozyme, HEL, ML; Peptides, Quantification; Frequency of HEL specific T-cells, Transgenic mice; MHC-Peptide per APC, Transgenic mice; Exogenous Peptides; Antigens; APC, Summary; Discussion [Image] [View with Perseus links] (0.69)

39 from The University of Michigan. University Library. Digital Library Production Service.

1. Miscellany: Dresden. Classical Dinners. Abbotsford in 1872. National Observatory. A Despotic Coroner., Appletons' journal: a magazine of general literature. [Text] [View with Perseus links] (2.59)

2. Anthon, Charles; Anthon's Classical Dictionary, Review, The Southern quarterly review. [Text] [View with Perseus links] (2.38)

3. A Dictionary of Urdu, Classical Hindi, and English: Searchable online version of John Platts' 1884 Oxford Dictionary of Urdu, Classical Hindi, and English developed by three CIC universities with the National Resource Centers for South Asia with Department of Education grant funding. Uses Unicode to represent Perso-Arabic script, a right-to-left script, intermingled with left-to-right roman script [Text] [View with Perseus links] (2.18)

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1 from University of Glasgow EPrint Archive

1. Smith, Vincent; Avian louse phylogeny (Phthiraptera: Ischnocera): A cladistic study based on morphology: The systematics and taxonomy of avian chewing lice from the suborder Ischnocera (Phthiraptera) is investigated. Comparative anatomy based on adult and instar morphology is used to explore both classical and novel homology hypotheses for a variety of character systems, including chaetotaxy, head shape, preantennal morphology and internal genitalia. These are critically examined within a phylogenetic context. The role of ontogeny in the development of the major character complexes of the head and abdomen is considered, and its implications for further work on the systematics of avian Ischnocera is discussed. Elliptic Fourier analysis is used to explore the evolution of louse head shape. Rates of heterochrony and the performance of alternative character state transformation series are evaluated. These data are used to build the first cladistic hypotheses for avian chewing lice (suborder Ischnocera). Generic and familial relationships are investigated for a diverse selection of ischnoceran taxa spanning 13 bird orders (32 bird families), with particular emphasis on the ischnoceran chewing lice of galliform, columbiform and tinamiform birds (families Goniodidae and Heptapsogasteridae). Comparison with host taxonomy reveals a series of complex host parasite associations which do not support a hypothesis of one to one cospeciation. However, interpretation of these comparisons is hampered by the fact that less than one thirtieth of the 2,700 species of avian ischnoceran lice were examined. Future prospects for understanding more about the coevolutionary relationships between lice and their hosts are considered. [Text] [View with Perseus links] (0.22)

1 from University of Illinois Library

1. Indelli, W.; Classical [Text] (2.82)

10 from University of Minnesota IMAGES

1. This object is held by: University of Minnesota Libraries, Performing Arts Archives, Front: Signed "John Z. Wood." Back: Stamped "Property of Twin City Scenic Co. - Minneapolis." "We have copy in shop." Stage term: Olios., Olio drop of a classical arbor overlooking a distant town. This piece has the same composition as Twin City Scenic Co. collection colored rendering accession #MSSC0014. [Text] (1.06)

2. This object is held by: University of Minnesota Libraries, Performing Arts Archives, Stage term: Gardens., Garden drop with a classical arbor and reflecting pools. [Text] (1.00)

3. This object is held by: University of Minnesota Libraries, Performing Arts Archives, Stage term: Olios., Olio drop. Patio with classical arbor, mountains, and city across water. [Text] (0.87)

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43 from Virginia Tech Electronic Thesis and Dissertation Collection

1. Adamec, Vaclav; THE EFFECT OF MATERNAL AND FETAL INBREEDING ON DYSTOCIA, CALF SURVIVAL, DAYS TO FIRST SERVICE AND NON-RETURN PERFORMANCE IN U.S. DAIRY CATTLE: Dr. Ronald E. Pearson, Dr. Stephen C. Nickerson, Dr. Bennet G. Cassell, Dr. Eric P. Smith, Dr. David R. Notter; (in English) Intensive selection for increased milk production over many generations has led to growing genetic similarity and increased relationships in dairy population. In the current study, inbreeding depression was estimated for number of days to first service, summit milk, conception by 70 days non-return, and calving rate with a linear mixed model (LMM) approach and for calving difficulty, calf mortality with a Bayesian threshold model (BTM) for categorical traits. Effectiveness of classical and unknown parentage group procedures to estimate inbreeding coefficients was evaluated depending on completeness of a 5-generation pedigree. A novel method derived from the classical formula to estimate inbreeding was utilized to evaluate completeness of pedigrees. Two different estimates of maternal inbreeding were fitted in separate models as a linear covariate in combined LMM analyses (Holstein registered and grade cows and Jersey cows) or separate analyses (registered Holstein cows) by parity (1-4) with fetal inbreeding. Impact of inbreeding type, model, data structure, and treatment of herd-year-season (HYS) on magnitude and size of inbreeding depression were assessed. Grade Holstein datasets were sampled and analyzed by percentage of pedigree present (0-30%, 30-70% and 70-100%). BTM analyses (sire-mgs) were performed using Gibbs sampling for parities 1, 2 and 3 fitting maternal inbreeding only. In LMM analyses of grade data, the least pedigree and diagonal A matrix performed the worst. Significant inbreeding effects were obtained in most traits in cows of parity 1. Fetal inbreeding depression was mostly lower than that from maternal inbreeding. Inbreeding depression in binary traits was the most difficult to evaluate. Analyses with non-additive effects included in LMM, for data by inbreeding level and by age group should be preferred to estimate inbreeding depression. In BTM inbreeding effects were strongly related to dam parity and calf sex. Largest effects were obtained from parity 1 cows giving birth to male calves (0.417% and 0.252% for dystocia and calf mortality) and then births to female calves (0.300% and 0.203% for dystocia and calf mortality). Female calves from mature cows were the least affected (0.131% and 0.005% for dystocia and calf mortality). Data structure was found to be a very important factor to attainment of convergence in distribution. [Text] [View with Perseus links] (0.92)

2. Jacobson, Stephanie Hildegarde Zadro; A Comparison of Early Childhood Assessments and A Standardized Measure For Program Evaluation: Javaid Kaiser, Marvin G. Cline, Ronald McKeen, Barbara Hutson, Victoria Fu; (in English) Traditionally, standardized achievement tests have been used to monitor program effectiveness. Recently, however, educators have questioned the appropriateness of standardized tests for this purpose, especially for programs designed for young children. Early childhood advocates suggest using developmentally appropriate assessments instead of standardized achievement tests for making classroom-level decisions about children and for program evaluation. Proponents, however, have not fully identified the psychometric properties of the assessments, certainly not for the purposes of program evaluation. Although developmentally appropriate assessments have been implemented in a number of classrooms across the country, few studies have verified their ability to discriminate among developmental levels. In addition, even fewer studies have addressed their use for evaluating program effectiveness. Using the records of 293 students from the local site of a National Transition Project and both classical test theory (CTT) and item response theory (IRT) procedures, three assessment instruments and a standardized test were examined. It was shown that the Concepts about Print portion of the Early Childhood Assessment Package, the Language Arts component of the kindergarten developmental progress reports, and the first grade Early Literacy Scale tasks are, in fact, developmental assessments. Additionally, IRT procedures located students on the developmental continuum underlying the assessments. Although classical ANCOVAs were unable to identify Treatment or Head Start program effects beyond the kindergarten year, IRT procedures showed that the expected proportion of students at the highest latent ability levels tended to be greater for students in Demonstration schools and Head Start graduates than their counterparts throughout kindergarten and first grade. A standardized reading achievement measure administered to the students in second grade, was unable to differentiate program effects through either classical or IRT procedures. This suggests that the concepts underlying standardized tests differ from those underlying developmentally appropriate assessments. As a result, the key issue to be resolved is which type of measure is more valid, that is, more appropriate, for evaluating early childhood programs. [Text] [View with Perseus links] (0.74)

3. Vantine, William L.; Managing the Risk of Failure in Complex Systems Insight into the Space Shuttle Challenger Failure: John A. Rohr, James F. Wolf, C. Howard Robins, Jr., Philip S. Kronenberg, William C. Adams; (in English) Abstract <p> This dissertation presents a new approach for identifying, assessing, mitigating, and managing the risks of failure in complex systems. It describes the paradigm commonly used today to explain such failures and proposes an alternative paradigm that expands the lens for viewing failures to include alternative theories derived from modern theories of physics. Further, it describes the foundation for each paradigm and illustrates how the paradigms may be applied to a particular system failure. <p> Today, system failure commonly is analyzed using a paradigm grounded in classical or Newtonian physics. This branch of science embraces the principles of reductionism, cause and effect, and determinism. Reductionism is used to dissect the system failure into its fundamental elements. The principle of cause and effect links the actions that led to the failure to the consequences that result. Analysts use determinism to establish the linear link from one event to another to form the chain that reveals the path from cause to consequence. As a result, each failure has a single cause and a single consequence. <p> An alternative paradigm, labeled contemporary, incorporates the Newtonian foundation of the classical paradigm, but it does not accept the principles as inviolate. Instead, this contemporary paradigm adopts the principles found in the theories of relativity, quantum mechanics, chaos, and complexity. These theories hold that any analysis of the failure is affected by the frame of reference of the observer. Causes may create non-linear effects and these effects may not be observable directly. In this paradigm, there are assumed to be multiple causes for any system failure. Each cause contributes to the failure to a degree that may not be measurable using techniques of classical physics. The failure itself generates multiple consequences that may be remote in place or time from the site of the failure, and which may affect multiple individuals and organizations. Further, these consequences, are not inevitable, but may be altered by actions taken prior to and responses taken after the occurrence of the failure. <p> The classical and contemporary paradigms are applied using a single embedded case study, the failure of the space shuttle Challenger. Sources, including literature and popular press articles published prior to and after the failure and NASA documents are reviewed to determine the utility of each paradigm. These reviews are supplemented by interviews with individuals involved in the failure and the official investigations that followed. <p> This dissertation demonstrates that a combination of the classical and contemporary paradigms provides a more complete, and more accurate, picture of system failure. This combination links the non-deterministic elements of system failure analysis to the more conventional, deterministic theories. This new framework recognizes that the complete prevention of failure cannot be achieved; instead it makes provisions for preparing for and responding to system failure. <p> [Text] [View with Perseus links] (0.47)

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494 from arXiv

1. Land, M. C.; Particles and Events in Classical Off-Shell Electrodynamics: Despite the many successes of the relativistic quantum theory developed by Horwitz, et. al., certain difficulties persist in the associated covariant classical mechanics. In this paper, we explore these difficulties through an examination of the classical Coulomb problem in the framework of off-shell electrodynamics. As the local gauge theory of a covariant quantum mechanics with evolution parameter $\tau$, off-shell electrodynamics constitutes a dynamical theory of spacetime events, interacting through five $\tau$-dependent pre-Maxwell potentials. We present a straightforward solution of the classical equations of motion, which is seen to be unsatisfactory, and reveals the essential difficulties in the formalism at the classical level. We then offer a new model of the particle current -- as a certain distribution of the event currents on the worldline -- which eliminates these difficulties and permits comparison of classical off-shell electrodynamics with the standard Maxwell theory. In this model, the fixed'' event induces a Yukawa-type potential, permitting a semi-classical identification of the pre-Maxwell time scale $\lambda$ with the inverse mass of the intervening photon. Numerical solutions to the equations of motion are compared with the standard Maxwell solutions, and are seen to coincide when $\lambda \gtrsim 10^{-6}$ seconds, providing an initial estimate of this parameter. It is also demonstrated that the proposed model provides a natural interpretation for the photon mass cut-off required for the renormalizability of the off-shell quantum electrodynamics., Comment: 21 pages, Latex, 3 Postscript figures [Text] [View with Perseus links] (3.59)

2. Aarts, Gert; Renormalizability of hot classical field theory: I discuss the possibility of using classical field theory to approximate hot, real-time quantum field theory. I calculate, in a scalar theory, the classical two point and four point function in perturbation theory. The counterterms needed to make the classical correlation functions finite are dictated by the superrenormalizability of the static theory. The classical expressions approximate the quantum ones, when the classical parameters are chosen according to the dimensional reduction matching rules. I end with an outlook to gauge theories., Comment: 5 pages, 1 eps figure. To appear in the Proceedings of Strong and Electroweak Matter '97, Eger, Hungary, 21-25 May 1997 [Text] [View with Perseus links] (3.25)

3. Ayal, Shai, Piran, Tsvi; Spherical Collapse of a Mass-Less Scalar Field With Semi-Classical Corrections: We investigate numerically spherically symmetric collapse of a scalar field in the semi-classical approximation. We first verify that our code reproduces the critical phenomena (the Choptuik effect) in the classical limit and black hole evaporation in the semi classical limit. We then investigate the effect of evaporation on the critical behavior. The introduction of the Planck length by the quantum theory suggests that the classical critical phenomena, which is based on a self similar structure, will disappear. Our results show that when quantum effects are not strong enough, critical behavior is observed. In the intermediate regime, evaporation is equivalent to a decrease of the initial amplitude. It doesn't change the echoing structure of near critical solutions. In the regime where black hole masses are low and the quantum effects are large, the semi classical approximation breaks down and has no physical meaning., Comment: 16 pages, 16 eps figures, LaTeX 2e using the caption and mathletters styles (included) [Text] [View with Perseus links] (2.60)

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