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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

I. ABSOLUTE-CONFIGURATION OF LOLINE ALKALOIDS; II. STRUCTURE OF NIC-2, A NEW NATURAL STEROID; III. SYNTHESIS OF FUROCOUMARINS

Morehead, Steven Ralph, 1947- January 1974 (has links)
No description available.
52

Finding Similar Protein Structures Efficiently and Effectively

Cui, Xuefeng 23 April 2014 (has links)
To assess the similarities and the differences among protein structures, a variety of structure alignment algorithms and programs have been designed and implemented. We introduce a low-resolution approach and a high-resolution approach to evaluate the similarities among protein structures. Our results show that both the low-resolution approach and the high-resolution approach outperform state-of-the-art methods. For the low-resolution approach, we eliminate false positives through the comparison of both local similarity and remote similarity with little compromise in speed. Two kinds of contact libraries (ContactLib) are introduced to fingerprint protein structures effectively and efficiently. Each contact group from the contact library consists of one local or two remote fragments and is represented by a concise vector. These vectors are then indexed and used to calculate a new combined hit-rate score to identify similar protein structures effectively and efficiently. We tested our ContactLibs on the high-quality protein structure subset of SCOP30, which contains 3,297 protein structures. For each protein structure of the subset, we retrieved its neighbor protein structures from the rest of the subset. The best area under the ROC curve, archived by a ContactLib, is as high as 0.960. This is a significant improvement over 0.747, the best result achieved by the state-of-the-art method, FragBag. For the high-resolution approach, our PROtein STructure Alignment method (PROSTA) relies on and verifies the fact that the optimal protein structure alignment always contains a small subset of aligned residue pairs, called a seed, such that the rotation and translation (ROTRAN), which minimizes the RMSD of the seed, yields both the optimal ROTRAN and the optimal alignment score. Thus, ROTRANs minimizing the RMSDs of small subsets of residues are sampled, and global alignments are calculated directly from the sampled ROTRANs. Moreover, our method incorporates remote information and filters similar ROTRANs (or alignments) by clustering, rather than by an exhaustive method, to overcome the computational inefficiency. Our high-resolution protein structure alignment method, when applied to optimizing the TM-score and the GDT-TS score, produces a significantly better result than state-of-the-art protein structure alignment methods. Specifically, if the highest TM-score found by TM-align is lower than 0.6 and the highest TM-score found by one of the tested methods is higher than 0.5, our alignment method tends to discover better protein structure alignments with (up to 0.21) higher TM-scores. In such cases, TM-align fails to find TM-scores higher than 0.5 with a probability of 42%; however, our alignment method fails the same task with a probability of only 2%. In addition, existing protein structure alignment scoring functions focus on atom coordinate similarity alone and simply ignore other important similarities, such as sequence similarity. Our scoring function has the capacity for incorporating multiple similarities into the scoring function. Our result shows that sequence similarity aids in finding high quality protein structure alignments that are more consistent with HOMSTRAD alignments, which are protein structure alignments examined by human experts. When atom coordinate similarity itself fails to find alignments with any consistency to HOMSTRAD alignments, our scoring function remains capable of finding alignments highly similar to, or even identical to, HOMSTRAD alignments.
53

It's all a plot : an examination of the usefulness of the popularly accepted structural paradigm in the practice of writing of a feature film script

Morris, Anthony Kevin January 2008 (has links)
This study took the widely-accepted, ‘industry standard’ Structural Paradigm of feature film plotting, and ‘road tested’ it, assessing its value as a tool in the process of actually writing a feature film script. The methodology employed was to write a feature film script (titled THE ARM THAT DOES THE HARM) and look to apply the Paradigm to the writing process. Journals recording the process were kept and peer assessment undertaken. The data from these sources was then analysed and conclusions drawn. The reason for and value of this study are that, while this Paradigm is widely espoused by screenwriting gurus, taught as part of film courses and applied as a tool of script assessment and review, there is very little documented evidence of its actual value to the practice of writing a script. My findings revealed that, though a useful reference point throughout, the Paradigm is most valuable during the early stages of story structuring and again, most particularly, when editing later drafts. An important outcome of this study was that it identified the Paradigm as a valuable tool, not a rule that must be adhered to, a series of points a narrative must be seen to ‘hit’ in order for it to be considered to have been told correctly. Further, this study demonstrated in practice how this tool can be applied. This study suggests that trying to force an evolving story into the confines of the Paradigm can inhibit the story from developing ‘organically’ from its characters. Rather, the Paradigm should be applied as a tool for helping shape stories that first and foremost should be character-driven.
54

Investigation of the electronic and thermal rearrangement properties of Spiro[2,4]Hepta-4,6-Dienes /

Crandall, Raymond K. January 1982 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1982. / Typescript. Includes bibliographical references (leaves 62-63).
55

Familie, Ehre und Macht : Konzept und soziale Wirklichkeit des Adels in der Stadt Quito (Ecuador) während der späten Kolonialzeit, 1765-1822 /

Büschges, Christian. January 1996 (has links)
Diss.--Philosophische Fakultät--Universität Köln, 1995. / Contient un choix de statistiques. notes bibliogr. Glossaire. Bibliogr. p. 303-318.
56

Étude et modélisation de structures MIS sur AsGa : influence de la recombinaison dans la zone de charge d'espace.

Krim, Fateh, January 1900 (has links)
Th. doct.-ing.--Électroninque--Grenoble--I.N.P., 1982. N°: DI 315.
57

The structure of benzylidene alpha methylglucoside and of 2:3 dimethylglucose

Purves, Clifford B. January 1929 (has links)
After discussing the condensation portion of methylglucoside with benzaldehyde and the chemistry of the product, the structure of benzylidene methylglucoside, together with that of the dimethyl glucose, is reviewed. A few observations upon the effect of the substitutions upon the molecular rotation of methylglucoside is then inserted before an account is given of the chemical behaviour of dimethyl glucose, as contrasted with that of the unsubstituted sugar. Finally, the experiments on which the Thesis is based, prefaced by notes explaining the technique adopted, complete the work.
58

Case Study: The Closing of the Arizona Interfaith Alliance for Worker Justice and Implications on Barriers to Civic Engagement in its Wake

January 2016 (has links)
abstract: The Arizona Interfaith Alliance for Worker Justice (AIAWJ) was a mediating structure for those who wanted to be civically engaged in the labor movement and other coalitions in Phoenix, Arizona. It not only served its constituents, but it integrated, educated, and empowered them. Due to lack of funding the AIAWJ closed in the summer of 2016. Many community members from marginalized neighborhoods, other concerned citizens, students, myself, and others participated in their first and only civic engagement opportunities through this organization and were subsequently left with no connections, a barrier to being civically engaged. Through interviews and secondary data research, the relationship between people, mediating structures, and civic engagement activity are examined. The key findings support existing research that emphasizes the importance of mediating structures when it comes to civic engagement. / Dissertation/Thesis / Masters Thesis Interdisciplinary Studies 2016
59

Debt Structure and Future Financing and Investment

January 2017 (has links)
abstract: I study the relation between firm debt structure and future external financing and investment. I find that greater reliance on long-term debt is associated with increased access to external financing and ability to undertake profitable investments. This contrasts with previous empirical results and theoretical predictions from the agency cost literature, but it is consistent with predictions regarding rollover risk. Furthermore, I find that firms with lower total debt (high debt capacity) have greater access to new financing and investment. Lower leverage increases future debt issues and capital expenditures, and firms do not fully rebalance by reducing the use of external financing sources such as equity. Finally, my results support the view that greater reliance on unsecured debt can increase future debt financing. Overall, my paper offers new insights into how aspects of debt structure, in particular maturity, are related ex-post to firms' ability to raise new financing and invest. / Dissertation/Thesis / Doctoral Dissertation Business Administration 2017
60

Analyse du comportement mécanique de l'interface entre un enduit d'isolation thermique innovant et son support structurel / Analysis of the mechanical behaviour of the interface between an innovative thermal insulating coating and its structural substrate

Eymard, Mathieu 02 December 2014 (has links)
Les recherches effectuées au cours de cette thèse s'inscrivent dans le cadre du projet FUI Parex-IT (PARement EXtérieur pour l'Isolation Thermique). Le but de ce projet est de développer un enduit d'isolation thermique par l'extérieur à fort pouvoir isolant pour la réhabilitation. Plus particulièrement, ces travaux concernent la caractérisation mécanique de l'accroche de cet enduit avec son support structurel. Celui-ci est appliqué par projection directe d'une couche de 4 cm d'épaisseur. En considérant un mur enduit, soumis à des sollicitations horizontales telles que le vent ou le séisme, ce type de mise en place implique une transmission d'efforts de la structure vers l'enduit isolant par l'interface entre les deux matériaux. La résistance de cette interface est donc considérée ici comme la zone critique pour une bonne pérennité du complexe. Parallèlement, une étude équivalente a été menée sur un enduit de finition classique, à titre comparatif. Deux échelles ont été prises en compte pour l'étude du comportement de cette interface. Une première à l'échelle locale dont l'objectif est de déterminer un critère de rupture de cette interface. Celle-ci a donc été soumise, expérimentalement, à différents états de contraintes entraînant sa rupture. Cependant, les différences importantes de propriétés mécaniques entre cet enduit et son support sont susceptibles, d'après la bibliographie, de provoquer des concentrations de contraintes du point de vue expérimental. Une analyse numérique a donc été réalisée afin de quantifier les écarts obtenus entre les critères expérimentaux et numériques, pour les deux matériaux testés. A l'échelle d'un mur, l'analyse s'est portée sur une maçonnerie soumise à des sollicitations de cisaillement dans son plan. L'objectif étant tout d'abord d'étudier le comportement d'un mur enduit, et de le comparer à une maçonnerie nue, de référence. Dans un deuxième temps, la pertinence des critères des interfaces support-enduits obtenus à l'échelle locale a été étudiée d'après une étude numérique. Les analyses par corrélation d'images numériques ont, de manière générale, permis de comparer les comportements expérimentaux et numériques pour faciliter la validation des modèles proposés. / This thesis takes part of the FUI project PAREX-IT (PARement EXtérieur pour l'Isolation Thermique). Its main purpose is to develop an efficient insulating coating from the outside, for refurbishment. More particularly, this work investigates the mechanical bond behaviour between this solution and its structural substrate. This thermal insulation is 4 cm thick and pneumatically placed. Considering a coated wall, solicited by wind or seismic loads, this configuration implies a load transfer from the structure to the insulating coating, through the interface between those two materials. The interfacial strength is though considered here as the critical area for a good sustainability of this complex. Meanwhile an equivalent study has been made on a more classical coating, by comparison. Two different scales have been studied. First, a local scale study to determine a failure criterion of this interface, which have been solicited in different states of stresses provoking its failure. However, the important differences of mechanical properties between the tested coatings and the mechanical support can, according to bibliography, provoke stress concentration. A numerical analysis has been conducted to quantify their influence on the parameters of the experimental criterion, for the two tested coatings. At a wall scale, a masonry submitted to shear loads was studied. The objective was to compare the behaviour between a coated wall and an uncoated one, considered as reference. In a second time, a numerical study was performed to confirm the criteria obtained at the local scale. Image correlation has been used to compare the experimental and numerical behaviours to facilitate modelling validation.

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