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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.
141

Well-Formed and Scalable Invasive Software Composition

Karol, Sven 18 May 2015 (has links)
Software components provide essential means to structure and organize software effectively. However, frequently, required component abstractions are not available in a programming language or system, or are not adequately combinable with each other. Invasive software composition (ISC) is a general approach to software composition that unifies component-like abstractions such as templates, aspects and macros. ISC is based on fragment composition, and composes programs and other software artifacts at the level of syntax trees. Therefore, a unifying fragment component model is related to the context-free grammar of a language to identify extension and variation points in syntax trees as well as valid component types. By doing so, fragment components can be composed by transformations at respective extension and variation points so that always valid composition results regarding the underlying context-free grammar are yielded. However, given a language’s context-free grammar, the composition result may still be incorrect. Context-sensitive constraints such as type constraints may be violated so that the program cannot be compiled and/or interpreted correctly. While a compiler can detect such errors after composition, it is difficult to relate them back to the original transformation step in the composition system, especially in the case of complex compositions with several hundreds of such steps. To tackle this problem, this thesis proposes well-formed ISC—an extension to ISC that uses reference attribute grammars (RAGs) to specify fragment component models and fragment contracts to guard compositions with context-sensitive constraints. Additionally, well-formed ISC provides composition strategies as a means to configure composition algorithms and handle interferences between composition steps. Developing ISC systems for complex languages such as programming languages is a complex undertaking. Composition-system developers need to supply or develop adequate language and parser specifications that can be processed by an ISC composition engine. Moreover, the specifications may need to be extended with rules for the intended composition abstractions. Current approaches to ISC require complete grammars to be able to compose fragments in the respective languages. Hence, the specifications need to be developed exhaustively before any component model can be supplied. To tackle this problem, this thesis introduces scalable ISC—a variant of ISC that uses island component models as a means to define component models for partially specified languages while still the whole language is supported. Additionally, a scalable workflow for agile composition-system development is proposed which supports a development of ISC systems in small increments using modular extensions. All theoretical concepts introduced in this thesis are implemented in the Skeletons and Application Templates framework SkAT. It supports “classic”, well-formed and scalable ISC by leveraging RAGs as its main specification and implementation language. Moreover, several composition systems based on SkAT are discussed, e.g., a well-formed composition system for Java and a C preprocessor-like macro language. In turn, those composition systems are used as composers in several example applications such as a library of parallel algorithmic skeletons.
142

Prédiction de performances d’applications de calcul distribué exécutées sur une architecture pair-à-pair / Performance prediction of distributed computing applications executed on a peer-to-peer architecture

Cornea, Bogdan Florin 08 December 2011 (has links)
Dans le domaine du calcul de haute performance, les architectures d’exécution sont en continuelle évolution. L’augmentation du nombre de nœuds de calcul, ou le choix d’une topologie réseau plus rapide représentent un investissement important tant en temps qu’en moyen financier. Les méthodes de prédiction de performances permettent de guider ce choix. En parallèle à ce développement, les systèmes HPC pair-à-pair (P2P) se sont également développés ces dernières années. Ce type d’architecture hétérogène permettrait la résolution des problèmes scientifiques pour un coût très faible par rapport au coût d’une architecture dédiée.Ce manuscrit présente une méthode nouvelle de prédiction de performances pour les applications réelles de calcul distribué, exécutées dans des conditions réelles. La prédiction prend en compte l’optimisation du compilateur. Les résultats sont extrapolables et ils sont obtenus pour un ralentissement réduit. Ce travail de recherche est implémenté dans un logiciel nouveau nommé dPerf. dPerf est capable de prédire les performances des applications C, C++ ou Fortran qui communiquent en utilisant les normes MPI ou P2P-SAP et qui s’exécutent sur une architecture cible pair à pair, hétérogène et décentralisée. La précision de cette contribution a été étudiée sur (i) la transformée Laplace, pour l’aspect séquentiel, (ii) le benchmark IS de NAS, pour l’aspect MPI, (iii) et le code de l’obstacle pour l’aspect calcul P2P décentralisé et l’extrapolation du nombre de nœuds. / In the field of high performance computing, the architectures evolve continuously. In order to increase the number of computing nodes or the network speed, an important investment must be considered, from both temporal and financial point of view. Performance prediction methods aim at assisting in finding the best trade-off for such an investment. At the same time, P2P HPC systems have known an increase in development. These heterogeneous architectures would allow solving scientific problems at a low cost, with respect to dedicated systems.The manuscript presents a new method for performance prediction. This method applies to real applications for distributed computing, considered in a real execution environment. This method uses information about the different compiler optimization levels. The prediction results are obtained with reduced slowdown and are scalable. This thesis took shape in the development of the dPerf tool. dPerf predicts the performances of C, C++, and Fortran application, which use MPI or P2P-SAP to communicate. The applications modeled by dPerf are meant for execution on P2P heterogeneous architectures, with a decentralized communication topology. The accuracy of dPerf has been studied on three applications: (i) the Laplace transform, for sequential codes, (ii) the NAS Integer Sort benchmark for distributed MPI programs, (iii) and the obstacle problem, for the decentralized P2P computing and the scaling of the number of computing nodes.
143

Métallation et substitution nucléophile aromatique des acides benzoïques non protégés : application à la synthèse totale de l’apogossypol / Metallation and nucleophilic aromatic substitution of unprotected benzoic acids : application to synthesis of apogossypol

Le, Tin Thanh 16 December 2011 (has links)
Dans le cadre d’un projet général concernant l’étude de la réactivité des acidesbenzoïques non protégés avec les organométalliques, la synthèse totale d’analoguesstructuraux de l’apogossypol mettant en jeu des réactions de métallation aromatique a étéétudiée ainsi que la réaction de substitution nucléophile aromatique des acides benzoïquesortho-fluorés et ortho-méthoxylés.Le gossypol, (1,1’,6,6’,7,7’-hexahydroxy-5,5’-di-iso-propyl-3,3’-diméthyl-2,2’-binaphtalène-8,8’-dicarboxaldéhyde), pigment principal des graines du cotonnier, existe sousla forme de deux atropoisomères et possède de multiples applications pharmaceutiques. Il estnotamment un inhibiteur efficace des protéines anti-apoptotiques de la famille Bcl-2. Legossypol déformylé ou apogossypol présente des propriétés similaires mais est plus stable,plus sélectif et moins toxique. Une méthode permettant de remplacer les groupes iso-propylesdu gossypol par des groupes structurellement proches a été mise au point. La stratégie retenuemet à profit les compétences du laboratoire dans le domaine des réactions de métallation etrepose sur la lithiation latérale de l’acide 4-hydroxy-6,7-diméthoxy-8-méthyl-2-naphtoïquepar le tétraméthylpipéridure de lithium. Divers dérivés 5,5’-didés-iso-propyl-5,5’-dialkylapogossypol racémiques ont été préparés selon cette méthode. La synthèse asymétriqued’analogues de l’apogossypol a également été étudiée et la voie de synthèse sélectionnéerepose sur le « concept lactone ». Un intermédiaire avancé de la synthèse, une lactonefonctionnalisée potentiellement réductible de façon asymétrique, a été préparée.La deuxième partie est consacrée à l’étude de la réaction de substitution nucléophilearomatique des acides benzoïques ortho-fluorés et ortho-méthoxylés (réaction SNArAB). Unerevue de la littérature des réactions de substitution nucléophile aromatique activée par lesesters est présentée. L’influence de substituants méthoxylés et halogénés (F, Cl, Br) sur lasélectivité SNAr/addition 1,2 a été évaluée. Il est montré que les acides 2-fluoro-6-halogénobenzoïques conduisent, par réaction avec les aryllithiens et les arylmagnésiens, auxproduits d’ipso-C2-substitution avec un excellent rendement et la réaction SNArAB permet unaccès efficace aux acides 3-halogéno-[1,1’-biphényl]-2-carboxyliques. Dans le cas de l’acide2,3-diméthoxybenzoïque, il a été découvert que la présence d’un substituant méthoxy enposition 3 permet de limiter la formation de cétone et le produit d’ipso-substitution est isoléavec un rendement correct. / As part of a program directed toward the study of the reactivity of unprotected benzoicacids with polar organometallics, the total racemic synthesis of apogossypol analogues bymetalation reactions was studied as well as the aromatic nucleophilic substitution reaction ofortho-fluoro- and ortho-methoxybenzoic acids (SNArAB reaction).Gossypol (1,1’,6,6’,7,7’-hexahydroxy-5,5’-di-iso-propyl-3,3’-diméthyl-2,2’-binaphtalène-8,8’-dicarboxaldéhyde) which is the main pigment of cotton seed, displaysmultiple pharmacological applications. It is a potent anti-apoptotic Bcl-2 protein inhibitor.The racemic route developed herein allows the replacement of the iso-propyl groups byvirtually any alkyl groups, providing a series of 5,5’-dides-iso-propyl-5,5’-dialkylapogossypolderivatives. Lateral metalation of 4-hydroxy-6,7-dimethoxy-8-methyl-2-naphthoic acid withLTMP is the key step of the synthesis. Atroposelective synthesis of apogossypol analoguewas also examined. The strategy relies on the “lactone concept” and involves a functionalizedlactone as a key intermediateThe influence of halogen atoms (F, Cl, Br) and methoxy groups on the 1,2-addition/SNArAB selectivity was examined. Treatment of 2-fluoro-6-halobenzoic acids withorganolithiums or Grignard reagents gives ipso-substituted products in excellent yields. Themethod allows the efficient preparation of 3-halo-[1,1’-biphenyl]-2-carboxylic acids and doesnot require protection of the carboxylate. Interestingly, the presence of an additional methoxyin C3 reduces the nucleophilic addition of the organometallic species to the carboxylate and2,3-dimethoxybenzoic acid affords ipso-substituted products in good yields.
144

Development of the Solution-Spray Flash-Vacuum-Pyrolysis Technique in the Synthesis of Allenyl Isothiocyanates and Synthesis of Complex 2-Amino-1,3-thiazole Derivatives / Entwicklung der Solution-Spray Blitzvakuumpyrolyse-Technik in der Synthese von Allenylisothiocyanaten und Synthese komplexer 2 Amino-1,3-thiazolderivate

Richter, Frank 27 July 2015 (has links) (PDF)
Gas-phase thermolysis is a long-known and well established method for the preparation of reactive species. It is, however, limited to relatively volatile substances, which are easily vaporised. In the present work, the solution-spray technique for preparative scale was developed. With this technique, it is possible to subject low-volatile substances, which hardly vaporise even under high-vacuum conditions, to gas-phase thermolysis. By utilising oil nozzles used in heating and burner systems, it was possible to integrate a stable solution-spray into the existing flash-vacuum-pyrolysis system. The influence of several variables, such as flow-rate, pressure, temperature and solvent was determined. The solution-spray technique was applied in [3,3]-sigmatropic rearrangements of certain propargyl thiocyanates to the corresponding allenyl isothiocyanates. Furthermore, the parent compound propa-1,2-dienyl isothiocyanate was reacted with various sterically demanding primary and secondary amines to form 2-amino-1,3-thiazoles in moderate to excellent yields. Based on this, a catalyst-free four-center three-component reaction was developed. 2-Amino-1,3-thiazoles with complex substituents in 5-position at the heterocyclic ring are formed. Reaction mechanisms are discussed to explain the occurance of a highly substituted 1,3-thiazine structure. The influence of reaction temperature, concentrations and solvent were determined and are also discussed. It was shown that 2-amino-5-methyl-1,3-thiazoles are the apparently first aromatic substance class, that readily undergoes Prins-type 1,3-dioxane ring-formation. / Die Gasphasenthermolyse ist eine lang bekannte und etablierte Methodik zur Synthese reaktiver Spezies. Sie ist allerdings auf flüchtige Substanzen mit einer guten Verdampfbarkeit beschränkt. Für schwerflüchtige Verbindungen, welche sich selbst im Hochvakuum nur mäßig oder gar nicht in die Gasphase bringen lassen, wurde in der vorliegenden Arbeit die Solution-Spray-Technik für die Anwendung im präparativen Maßstab entwickelt. Unter Verwendung von Ölzerstäuberdüsen, wie sie in der Heizungs- und Brennertechnik Anwendung finden, wurde die Erzeugung eines stabilen Lösungs-Sprays in die vorhandene Blitzvakuumpyrolyse-Technik integriert. Der Einfluss verschiedener Variablen, wie Flussrate, Druck, Temperatur und Lösungsmittel wurde untersucht. Die Solution-Spray-Technik wurde für die [3,3]-sigmatrope Umlagerung bestimmter Propargylthiocyanate zu Allenyl-isothiocyanaten angewendet. Des Weiteren wurde Propa-1,2-dienylisothiocyanat – das einfachste Allenylisothiocyanat – mit diversen sterisch anspruchsvollen primären und sekundären Aminen in mäßigen bis exzellenten Ausbeuten zu 2-Amino-1,3-thiazolen umgesetzt. Darauf aufbauend konnte eine Vier-Zentren-drei-Komponenten-Reaktion entwickelt werden. Es entstehen in hohen Ausbeuten 2-Amino-1,3-thiazole mit komplexen Substituenten an der 5-Position des Heterocyclus. Reaktionsmechanismen werden diskutiert um die alternative Bildung einer hochsubstituierten 1,3-Thiazinstruktur zu erklären. Der Einfluss von Reaktionstemperatur, Konzentration und Lösungsmittel auf das Produktverhältnis wurde ebenfalls untersucht und wird diskutiert. Es konnte gezeigt werden, dass 2-Amino-5-methyl-1,3-thiazole als offenbar erste aromatische Substanzklasse sehr gute Substrate für die Bildung von 1,3-Dioxanen nach Prins darstellen.
145

L'adaptation des étudiants en période de transition : une étude comparative franco-canadienne des étudiants primo-entrants et des étudiants internationaux vietnamiens / Students' adaptation in transition : a French-Canadian comparison between freshmen students and Vietnamese international students

Brisset, Camille 10 December 2009 (has links)
Cette thèse porte sur l’adaptation des étudiants en période de transition. Elle repose sur une comparaison franco-canadienne entre étudiants primo-entrants et étudiants internationaux vietnamiens. Dans l’objectif d’apporter un éclairage nouveau sur les processus de leur adaptation, nous avons intégré deux modèles théoriques permettant de distinguer deux niveaux d’adaptation, l’un dit « local » commun à tous les étudiants, l’autre dit « international » spécifique aux Vietnamiens (Black, Mendenhall & Oddou, 1991), dans lesquels viennent s’imbriquer deux dimensions du processus : l’adaptation psychologique et l’adaptation socioculturelle (Ward & Searle, 1991). La personnalité anxieuse, suivie de l’attachement adulte et des tracas quotidiens, apparaissent comme le fondement explicatif de l’adaptation des étudiants, quels qu’ils soient, tant à un niveau psychologique que socioculturel. A ces aspects « locaux » pour les Vietnamiens, s’ajoutent deux enjeux interculturels : l’identification à la culture d’origine et les différents réseaux de socialisation. Les résultats soulignent également pour les différents groupes d’étudiants une fragilisation des modèles internes de l’attachement, des différences culturelles dans leurs potentialités à former un corps étudiant et à se socialiser au sein de l’université ainsi que la présence d’individus à risques : ces derniers seraient dans l’incapacité de faire face efficacement au stress induit par la période de transition. / This dissertation focuses on students’ adaptation in transition. It is based on a French-Canadian comparison between freshmen students and international Vietnamese students. With the aim to shed a new light on the process of their adaptation, we integrated two theoretical models which allowed us to distinguish two levels of adaptation, one considered as “local” and common to all students, the other as “international” and specific to Vietnamese students (Black, Mendenhall & Oddou, 1991), in which are embedded two dimensions: psychological adaptation and sociocultural adaptation (Ward & Searle, 1991). Anxious personality, followed by adult attachment and daily hassles, appeared as the root of students’ adaptation both at a psychological and sociocultural level. In addition to these “local” aspects, Vietnamese have to deal with two cross-cultural issues: their identification with culture of origin and the different social networks in their environment. Results also highlighted for all students a weakening in their working models of attachment, cultural differences in their potential to form a student body and to socialize within the university and, the existence of individuals “at risk”: these students appeared to be unable to cope effectively with the stress induced by the transition. / Lu?n án này d? c?p d?n s? h?i nh?p c?a sinh viên trong quá trình chuy?n d?i. Lu?n án du?c th?c hi?n d?a trên m?t so sánh Pháp và Canada gi?a nh?ng sinh viên m?i vào d?i h?c và sinh viên qu?c t? Vi?t Nam. V?i mong mu?n dem l?i m?t cái nhìn m?i m? v? qúa trình h?i nh?p c?a h?, chúng tôi dã trình bày hai mô hình lý thuy?t nh?m phân bi?t hai m?c d? h?i nh?p, m?t « mô hình c?c b? » chung cho m?i sinh viên và m?t « mô hình qu?c t? » d?c trung cho sinh viên Vi?t Nam (Black, Mendenhall & Oddou, 1991). Trong hai mô hình này, hai m?t c?a quá trình dan xen l?n nhau : s? h?i nh?p tâm lý và s? h?i nh?p van hóa xã h?i (Ward & Searle, 1991). Tính cách hay lo, ti?p d?n là s? g?n bó sâu s?c và nh?ng khó khan trong cu?c s?ng thu?ng ngày là co s? lý gi?i cho s? h?i nh?p c?a sinh viên c? v? m?t tâm lý và van hóa xã h?i. ? khía c?nh « c?c b?», sinh viên Vi?t Nam còn ph?i d?i phó v?i hai v?n d? mang tính ch?t liên van hóa : s? d?ng nh?t v?i n?n van hóa g?c và các m?ng xa h?i khác nhau. K?t qu? c?a lu?n án dã nh?n m?nh r?ng d?i v?i nh?ng nhóm sinh viên khác nhau, có s? không b?n v?ng c?a các m?u bên trong c?a các m?i liên h? (working models of attachment), c?a s? khác bi?t v? van hóa trong xu hu?ng hình thành m?t t?p th? sinh viên (student body) và xu hu?ng xã h?i hóa trong tru?ng d?i h?c cung nhu là s? t?n t?i nh?ng cá nhân thu?ng xuyên có v?n d?, nhi?u tâm : nh?ng sinh viên này du?ng nhu không th? d?i phó m?t cách hi?u qu? v?i nh?ng cang th?ng trong quá trình chuy?n d?i này.
146

Interaktivní interpret jazyka C / C Language Interactive Interpreter

Blažek, Martin January 2008 (has links)
This master's thesis deals with implementation of ISO C99 language interpreter. The goal of this thesis is to provide support of education in C language programming and fast algorithm prototyping. It enables students to create own C programs and to experiment with language constructions without compiling. User interface includes editor and simple debugger. The interpreter is implemented in a novel grammar development environment written in Java language - ANTLRWorks which includes ANTLR language tool.
147

IMPLEMENTING NETCONF AND YANG ON CUSTOM EMBEDDED SYSTEMS

Georges, Krister, Jahnstedt, Per January 2023 (has links)
Simple Network Management Protocol (SNMP) has been the traditional approach for configuring and monitoring network devices, but its limitations in security and automation have driven the exploration of alternative solutions. The Network Configuration Protocol (NETCONF) and Yet Another Next Generation (YANG) data modeling language significantly improve security and automation capabilities. This thesis aims to investigate the feasibility of implementing a NETCONF server on the Anybus CompactCom (ABCC) Industrial Internet of Things (IIoT) Security module, an embedded device with limited processing power and memory, running on a custom operating system, and using open source projects with MbedTLS as the cryptographic primitive library. The project will assess implementing a YANG model to describe the ABCC’s configurable interface, connecting with a NETCONF client to exchange capabilities, monitoring specific attributes or interfaces on the device, and invoking remote procedure call (RPC) commands to configure the ABCC settings. The goal is to provide a proof of concept and contribute to the growing trend of adopting NETCONF and YANG in the industry, particularly for the Industrial Internet of Things (IIoT) platform of Hardware Meets Software (HMS).
148

From Copper to Gold: Identification and Characterization of Coinage-Metal Ate Complexes by ESI Mass Spectrometry and Gas-Phase Fragmentation Experiments

Weske, Sebastian 30 January 2019 (has links)
No description available.
149

Development of the Solution-Spray Flash-Vacuum-Pyrolysis Technique in the Synthesis of Allenyl Isothiocyanates and Synthesis of Complex 2-Amino-1,3-thiazole Derivatives

Richter, Frank 29 June 2015 (has links)
Gas-phase thermolysis is a long-known and well established method for the preparation of reactive species. It is, however, limited to relatively volatile substances, which are easily vaporised. In the present work, the solution-spray technique for preparative scale was developed. With this technique, it is possible to subject low-volatile substances, which hardly vaporise even under high-vacuum conditions, to gas-phase thermolysis. By utilising oil nozzles used in heating and burner systems, it was possible to integrate a stable solution-spray into the existing flash-vacuum-pyrolysis system. The influence of several variables, such as flow-rate, pressure, temperature and solvent was determined. The solution-spray technique was applied in [3,3]-sigmatropic rearrangements of certain propargyl thiocyanates to the corresponding allenyl isothiocyanates. Furthermore, the parent compound propa-1,2-dienyl isothiocyanate was reacted with various sterically demanding primary and secondary amines to form 2-amino-1,3-thiazoles in moderate to excellent yields. Based on this, a catalyst-free four-center three-component reaction was developed. 2-Amino-1,3-thiazoles with complex substituents in 5-position at the heterocyclic ring are formed. Reaction mechanisms are discussed to explain the occurance of a highly substituted 1,3-thiazine structure. The influence of reaction temperature, concentrations and solvent were determined and are also discussed. It was shown that 2-amino-5-methyl-1,3-thiazoles are the apparently first aromatic substance class, that readily undergoes Prins-type 1,3-dioxane ring-formation. / Die Gasphasenthermolyse ist eine lang bekannte und etablierte Methodik zur Synthese reaktiver Spezies. Sie ist allerdings auf flüchtige Substanzen mit einer guten Verdampfbarkeit beschränkt. Für schwerflüchtige Verbindungen, welche sich selbst im Hochvakuum nur mäßig oder gar nicht in die Gasphase bringen lassen, wurde in der vorliegenden Arbeit die Solution-Spray-Technik für die Anwendung im präparativen Maßstab entwickelt. Unter Verwendung von Ölzerstäuberdüsen, wie sie in der Heizungs- und Brennertechnik Anwendung finden, wurde die Erzeugung eines stabilen Lösungs-Sprays in die vorhandene Blitzvakuumpyrolyse-Technik integriert. Der Einfluss verschiedener Variablen, wie Flussrate, Druck, Temperatur und Lösungsmittel wurde untersucht. Die Solution-Spray-Technik wurde für die [3,3]-sigmatrope Umlagerung bestimmter Propargylthiocyanate zu Allenyl-isothiocyanaten angewendet. Des Weiteren wurde Propa-1,2-dienylisothiocyanat – das einfachste Allenylisothiocyanat – mit diversen sterisch anspruchsvollen primären und sekundären Aminen in mäßigen bis exzellenten Ausbeuten zu 2-Amino-1,3-thiazolen umgesetzt. Darauf aufbauend konnte eine Vier-Zentren-drei-Komponenten-Reaktion entwickelt werden. Es entstehen in hohen Ausbeuten 2-Amino-1,3-thiazole mit komplexen Substituenten an der 5-Position des Heterocyclus. Reaktionsmechanismen werden diskutiert um die alternative Bildung einer hochsubstituierten 1,3-Thiazinstruktur zu erklären. Der Einfluss von Reaktionstemperatur, Konzentration und Lösungsmittel auf das Produktverhältnis wurde ebenfalls untersucht und wird diskutiert. Es konnte gezeigt werden, dass 2-Amino-5-methyl-1,3-thiazole als offenbar erste aromatische Substanzklasse sehr gute Substrate für die Bildung von 1,3-Dioxanen nach Prins darstellen.

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