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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.
11

Ingénierie dirigée par les modèles basée sur les templates / Template based model driven engineering

Allon, Matthieu 04 October 2018 (has links)
Pour répondre à la complexité grandissante des systèmes, la réutilisation de modèles est employée dans les phases amont d’analyse et de conception. Dans cette thèse, nous nous intéressons à cette réutilisation en privilégiant les modèles paramétrés que sont les templates. Ceux-ci expriment des connaissances générales applicables à différents contextes. Sur la base des ‘aspectual templates’ possédant un modèle en paramètre, nous proposons une ingénierie dédiée. Celle-ci est structurée autour d’un dépôt de modèles et de deux espaces de conception : celui des templates et celui des modèles applicatifs, chaque espace supportant des activités de modélisation spécifiques. Nous contribuons à cette ingénierie en approfondissant trois axes. Tout d’abord, en examinant la relation ‘bind’ des templates UML, nous isolons l’instanciation comme opération de plein droit pour construire un modèle basé sur la structure du template. Les questions d’instanciation partielle et de séquences d’instanciation sont aussi examinées. Ensuite, pour répondre à des besoins d’évolution de modèles, nous proposons des opérateurs pour détecter et supprimer des templates dans un modèle. Enfin, nous étudions l’application de templates sur une hiérarchie de modèles dont les usages se rencontrent dans le versionnement et la modélisation en équipe. Pour faciliter ces usages, des règles définissant la validité de telles applications et leurs effets sur les relations entre leurs modèles résultats sont données. Nous appliquons cette ingénierie en proposant des opérateurs, leur mise en œuvre dans une technologie réutilisable et leur expérimentation en modélisant un serveur REST d’agrégation d’informations. / Against the growing complexity of systems, model reuse is often used in the analysis and design steps of software development. In this thesis, we explore this kind of reuse by focusing on templates which are parameterized models. Templates capture general knowledge that can be adapted to various application contexts. On the basis of ‘aspectual templates’ which have a model as parameter, we propose a dedicated engineering. This one is structured around a model repository and two design spaces : one for templates one and another for application models, each space supporting specific modeling activities. We contribute to this engineering by studying three topics First, through the analysis of the UML ‘bind’ relationship, we isolate instantiation as a first-class operation to build a model based on the template structure. Questions about partial instantiation and instantiation sequences are further examined. Then, in order to ease model understanding and evolution, we provide operators for detecting and deleting templates inside models. Finally, we study the application of templates on model hierarchies which occurs in model versioning and team modeling. To facilitate these uses, rules defining the validity of such application and their effects on the relations between resulting models are given. We apply this engineering by presenting corresponding operators, their implementation in a reusable technology and their experimentation to model a REST server of data curation.
12

Investigation of molecular interactions with molecularly imprinted polymers

Myint, Mo Aung, n/a January 2009 (has links)
Currently, very little information is available for an in-depth understanding of the molecular binding interactions with molecularly imprinted polymers (MIPs). To address this issue MIPs that have high binding affinities for their template compounds were made so that the nature of these interactions could be elucidated using spectroscopic techniques. 12 functional MIPs were prepared using a series of azobenzene and anthracenyl derivatives as the templates. Affinities of these MIPs for the corresponding templates and analogues were determined by performing batch and competitive binding tests. It was found that extensively conjugated compounds that contain at least two OH groups, an electron-withdrawing substituent and have limited conformational freedom were effective templates. The most efficient MIP, M34, was prepared with 4-[(4-nitrophenyl)azo]-1,2-benzenediol (12). M34 exhibited high affinities for azobenzene derivatives of catechol, and bound those that did not contain non electron-withdrawing substituents more specifically. M34 did not lose affinity for 12 in the presence of analogues, and vice versa, in competitive binding tests. These observations suggested a distribution of different binding sites on M34. M34 bound substrates rapidly, which was attributed to its highly porous polymer matrix giving ready access to binding sites. Formation of the porous matrix was facilitated by the use of DMF as the porogen in the preparation of M34. DMF is not a conventional choice of porogen because use of such highly polar H-bonding solvents is thought to disrupt complexation between template and polymer precursors, which is required for the formation of binding sites. Significant changes in the wavenumbers and the intensities of absorption bands assigned to the catechol substructure of 12 were observed in the FT-Raman spectra of 12 bound to M34. These findings suggested that the catechol substructure was responsible for interactions of 12 with M34 that are critical to rebinding and imprinting. In-situ analyses of dithranol (8) being removed from and bound to its MIP, M23, were performed using ATR-IR spectroscopy. Only one band, assigned to the aromatic substructure of 8, was not obstructed by solvent bands in the spectra of unwashed M23 and washed M23 that was treated with the rebinding solution. The wavenumbers of the corresponding bands in the two spectra were significantly different. This observation suggested that there were differences in the vibrational characteristics of 8 bound to M23 under the two conditions. Evidence was found for H-bonding between OH groups of 8 and C=O group of methacrylic acid using transmission FT-IR spectroscopy. However, no evidence was found that showed significant interactions between 12 and 2-vinylpyridine. Methacrylic acid and 2-vinylpyridine were used as the functional monomers in the preparations of M23 and M34. The FT-IR spectra of mixtures of 12 and 4-vinylpyridine showed three new bands assigned to H-bonded OH stretches. These observations indicated that 4-vinylpyridine H-bonds with 12, and would be a more effective functional monomer than 2-vinylpyridine in the preparation of the MIPs for 12. Titration of 12 with 2-vinylpyridine was analysed by �H NMR spectroscopy. Only small changes to the signals of the corresponding compounds were observed. This lack of change was attributed to the use of d₇DMF, which would compete against 2-vinylpyridine for H-bonding interactions. The findings made using ATR-IR spectroscopy and FT-Raman were novel because previously reported data on bound templates obtained using the corresponding techniques did not show changes in the vibrational characteristics of templates as they bind to MIPs. This investigation has shown that rebinding and spectroscopic studies can provide information about the nature of the binding interactions in MIPs.
13

Studies toward biomimetic claisen condensation using nucleic acid templates and ribozyme catalysis

Ryu, Youngha 29 August 2005 (has links)
Many different experimental approaches were attempted to achieve carbon-carbon bond formation by nucleic acid template-directed reactions and ribozyme catalysis as potential lipid synthesizing machineries in the RNA world. A novel biomimetic condition for decarboxylative Claisen condensation in polyketide biosynthesis was discovered. The reaction of a malonic acid half oxyester with a Nhydroxysuccinmidyl ester forming reagent resulted in self-condensation to provide the corresponding 1,3-acetonedicarboxylic acid diester in the absence of a divalent metal chelator or a coordinating solvent. The decarboxylative Claisen condensation of malonyl adenosine using a poly-U template in solution or with immobilized poly-U was attempted. Various analytical methods demonstrated that malonyl adenosine underwent an exclusive hydrolysis reaction instead of condensation in the given conditions. Similar results were observed for the reaction of malonyl-CoA with acetyl-CoA on poly-U templates. No evidence for the decarboxylative Claisen condensation was observed by a DNA-templated system although a double helical structure of DNA duplex was proven to facilitate a bimolecular reaction by offering a favorable proximity effect. Therefore, it seems that the unsuccessful condensation resulted not from the bad template effect but from the intrinsic properties of the decarboxylative Claisen condensation reaction itself. Two tRNA molecules loaded with a malonic acid were prepared by ligation of truncated tRNAs with malonylated dinucletides. Our initial attempts to probe carbon-carbon bond formation by subjecting malonylated tRNAs to the in vitro translational machinery were not successful. Novel carbon isosteres of α-amino acids are suggested as a potential source of a more stable and reactive carbanion for future experiments. Isoprenoid conjugates of nucleoside 5??-diphosphates, which were proposed as either an initiator nucleotide or substrate molecule for in vitro selection of prenyl-transferase ribozyme were prepared by one step nucleophilic displacement reactions. A random DNA pool was constructed for selection of a ketosynthase ribozyme. A substrate bearing a biotin tag was prepared by one-step conjugation. Hig-tagged T7 RNA polymerase was expressed and purified for a large scale transcription reaction. In vitro transcription of the random DNA pool with a 5??-thiol modified GMP analogue as an initiator nucleotide produced a thiol-modified random RNA library.
14

Studies toward biomimetic claisen condensation using nucleic acid templates and ribozyme catalysis

Ryu, Youngha 29 August 2005 (has links)
Many different experimental approaches were attempted to achieve carbon-carbon bond formation by nucleic acid template-directed reactions and ribozyme catalysis as potential lipid synthesizing machineries in the RNA world. A novel biomimetic condition for decarboxylative Claisen condensation in polyketide biosynthesis was discovered. The reaction of a malonic acid half oxyester with a Nhydroxysuccinmidyl ester forming reagent resulted in self-condensation to provide the corresponding 1,3-acetonedicarboxylic acid diester in the absence of a divalent metal chelator or a coordinating solvent. The decarboxylative Claisen condensation of malonyl adenosine using a poly-U template in solution or with immobilized poly-U was attempted. Various analytical methods demonstrated that malonyl adenosine underwent an exclusive hydrolysis reaction instead of condensation in the given conditions. Similar results were observed for the reaction of malonyl-CoA with acetyl-CoA on poly-U templates. No evidence for the decarboxylative Claisen condensation was observed by a DNA-templated system although a double helical structure of DNA duplex was proven to facilitate a bimolecular reaction by offering a favorable proximity effect. Therefore, it seems that the unsuccessful condensation resulted not from the bad template effect but from the intrinsic properties of the decarboxylative Claisen condensation reaction itself. Two tRNA molecules loaded with a malonic acid were prepared by ligation of truncated tRNAs with malonylated dinucletides. Our initial attempts to probe carbon-carbon bond formation by subjecting malonylated tRNAs to the in vitro translational machinery were not successful. Novel carbon isosteres of α-amino acids are suggested as a potential source of a more stable and reactive carbanion for future experiments. Isoprenoid conjugates of nucleoside 5??-diphosphates, which were proposed as either an initiator nucleotide or substrate molecule for in vitro selection of prenyl-transferase ribozyme were prepared by one step nucleophilic displacement reactions. A random DNA pool was constructed for selection of a ketosynthase ribozyme. A substrate bearing a biotin tag was prepared by one-step conjugation. Hig-tagged T7 RNA polymerase was expressed and purified for a large scale transcription reaction. In vitro transcription of the random DNA pool with a 5??-thiol modified GMP analogue as an initiator nucleotide produced a thiol-modified random RNA library.
15

A combinational framework for parallel programming using algorithmic skeletons

Hamdan, Mohammad M. January 2000 (has links)
No description available.
16

Investigation of molecular interactions with molecularly imprinted polymers

Myint, Mo Aung, n/a January 2009 (has links)
Currently, very little information is available for an in-depth understanding of the molecular binding interactions with molecularly imprinted polymers (MIPs). To address this issue MIPs that have high binding affinities for their template compounds were made so that the nature of these interactions could be elucidated using spectroscopic techniques. 12 functional MIPs were prepared using a series of azobenzene and anthracenyl derivatives as the templates. Affinities of these MIPs for the corresponding templates and analogues were determined by performing batch and competitive binding tests. It was found that extensively conjugated compounds that contain at least two OH groups, an electron-withdrawing substituent and have limited conformational freedom were effective templates. The most efficient MIP, M34, was prepared with 4-[(4-nitrophenyl)azo]-1,2-benzenediol (12). M34 exhibited high affinities for azobenzene derivatives of catechol, and bound those that did not contain non electron-withdrawing substituents more specifically. M34 did not lose affinity for 12 in the presence of analogues, and vice versa, in competitive binding tests. These observations suggested a distribution of different binding sites on M34. M34 bound substrates rapidly, which was attributed to its highly porous polymer matrix giving ready access to binding sites. Formation of the porous matrix was facilitated by the use of DMF as the porogen in the preparation of M34. DMF is not a conventional choice of porogen because use of such highly polar H-bonding solvents is thought to disrupt complexation between template and polymer precursors, which is required for the formation of binding sites. Significant changes in the wavenumbers and the intensities of absorption bands assigned to the catechol substructure of 12 were observed in the FT-Raman spectra of 12 bound to M34. These findings suggested that the catechol substructure was responsible for interactions of 12 with M34 that are critical to rebinding and imprinting. In-situ analyses of dithranol (8) being removed from and bound to its MIP, M23, were performed using ATR-IR spectroscopy. Only one band, assigned to the aromatic substructure of 8, was not obstructed by solvent bands in the spectra of unwashed M23 and washed M23 that was treated with the rebinding solution. The wavenumbers of the corresponding bands in the two spectra were significantly different. This observation suggested that there were differences in the vibrational characteristics of 8 bound to M23 under the two conditions. Evidence was found for H-bonding between OH groups of 8 and C=O group of methacrylic acid using transmission FT-IR spectroscopy. However, no evidence was found that showed significant interactions between 12 and 2-vinylpyridine. Methacrylic acid and 2-vinylpyridine were used as the functional monomers in the preparations of M23 and M34. The FT-IR spectra of mixtures of 12 and 4-vinylpyridine showed three new bands assigned to H-bonded OH stretches. These observations indicated that 4-vinylpyridine H-bonds with 12, and would be a more effective functional monomer than 2-vinylpyridine in the preparation of the MIPs for 12. Titration of 12 with 2-vinylpyridine was analysed by �H NMR spectroscopy. Only small changes to the signals of the corresponding compounds were observed. This lack of change was attributed to the use of d₇DMF, which would compete against 2-vinylpyridine for H-bonding interactions. The findings made using ATR-IR spectroscopy and FT-Raman were novel because previously reported data on bound templates obtained using the corresponding techniques did not show changes in the vibrational characteristics of templates as they bind to MIPs. This investigation has shown that rebinding and spectroscopic studies can provide information about the nature of the binding interactions in MIPs.
17

Capturing molecules with templated materials analysis and rational design of molecularly imprinted polymers /

Wei, Shuting. January 2007 (has links)
Thesis (Ph.D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008. / Committee Chair: Boris Mizaikoff; Committee Member: Andrew Lyon; Committee Member: Ching-Hua Huang; Committee Member: David Collard; Committee Member: Facundo M. Fernandez.
18

Directed assembly host-guest chemistry, nanowires, and polymeric templates /

Jordan, Brian J., January 2009 (has links)
Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Includes bibliographical references (p. 98-113). Print copy also available.
19

Geração de simuladores de filas para diferentes contextos com estudo de casos para redes de computadores / Queues simulators generation for different contexts with computer networks case studies

Furlanetto, Gabriel Covello [UNESP] 05 May 2016 (has links)
Submitted by Gabriel Covello Furlanetto null (gcovellofurlanetto@gmail.com) on 2016-05-20T20:07:58Z No. of bitstreams: 1 Dissertacao_Final_Ficha.pdf: 2242577 bytes, checksum: 8f000a5c9f83c616b8a62659fa69d4ba (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-24T13:12:20Z (GMT) No. of bitstreams: 1 furnlanetto_gc_me_sjrp.pdf: 2242577 bytes, checksum: 8f000a5c9f83c616b8a62659fa69d4ba (MD5) / Made available in DSpace on 2016-05-24T13:12:20Z (GMT). No. of bitstreams: 1 furnlanetto_gc_me_sjrp.pdf: 2242577 bytes, checksum: 8f000a5c9f83c616b8a62659fa69d4ba (MD5) Previous issue date: 2016-05-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A busca por aprimorar o desenvolvimento de aplicações complexas tem aumentado gradativamente. Além disso, procura-se a redução de gastos ao implementar a aplicação, como também o aumento da segurança, o que torna muito importante a técnica de solução de modelos e a simulação de sistemas. Isso ocorre principalmente nas áreas comerciais, industriais e com finalidade de pesquisa. Visando facilitar a utilização da técnica de solução de modelos e a simulação de sistemas, neste projeto é apresentado o desenvolvimento de um gerador de simuladores baseado em filas, o Yasc (Yes, a simulator’s compiler). Esta ferramenta possibilita a construção de aplicações capazes de solucionar os problemas ditos anteriormente de maneira simples e sem a necessidade de codificação. Assim, a partir de parâmetros informados pelo usuário como entrada, o gerador fornece, como saída, uma ferramenta de simulação. Apresenta-se também um estudo de caso de redes de computadores em que o Yasc, com sua implementação já finalizada, foi utilizado para gerar simuladores de redes e para realizar a solução de modelos e simulação de ambientes reais, cujos resultados foram comparados aos de outro simulador específico da área, o NS-3 (Network Simulator). / The search to improve the development of complex applications has gradually increased. It also seeks to reduce costs by implementing the application, and seeks as well to increase security, which makes it very important to model solution technique and systems simulation. This occurs in the commercial, industrial and research-purposed areas. To facilitate the models solution technique and the simulation of systems, this project presented the development of a simulator generator based on queues, the Yasc (Yes, a simulator’s compiler). This tool makes it possible to generate applications that can simply solve problems mentioned before without coding. Thus, based on parameters from the user’s input, the generator provide, as output, a simulation tool. Furthermore, we present a case study of computer networks where the Yasc, with your finished implementation, was used to generate network simulators and to perform models solution and simulations of real enviroments, whose results were compared to other specific simulator area, the NS-3 (Network Simulator).
20

Semi-automated service creation for cloud computing

AZEVÊDO, Ernani Madureira de 31 January 2010 (has links)
Made available in DSpace on 2014-06-12T15:57:46Z (GMT). No. of bitstreams: 2 arquivo3224_1.pdf: 1528247 bytes, checksum: a3554156b6142706a9da81ae71bcfd08 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Faculdade de Amparo à Ciência e Tecnologia do Estado de Pernambuco / Atualmente, os computadores vêm experimentando um aumento de capacidades, apesar de passarem por constante miniaturização e ganho de mobilidade. Em paralelo, a velocidade e a confiabilidade das conexões evoluem a passos largos. Para explorar esta nova relação entre comunicação em rede e processamento foi desenvolvido o conceito de computação em nuvem, na qual os serviços são oferecidos através de uma rede difusa e os consumidores destes não têm ciência de como os provedores realizam suas atividades. Devido à natureza heterogênea deste paradigma de provisão e consumo, a descrição e criação desta categoria de serviços têm sua dificuldade aumentada, visto que os produtos de diversos domínios devem funcionar sobre plataformas não padronizadas e ser oferecidos a consumidores diversos de forma direta, contudo mantendo sua funcionalidade. O uso de padrões é uma solução bastante difundida nos mais diversos ramos de criação de processos, pois prega o reuso de trabalho de desenvolvimento, dando um suporte histórico a cada novo processo criado a partir de um padrão. Este trabalho propõe uma forma de acelerar o desenvolvimento e a implantação de serviços para computação em nuvem através da divisão da criação em três etapas. As etapas relacionadas à criação são semiautomatizadas pelo uso de padrões de projeto e de desenvolvimento, enquanto a etapa de implantação é totalmente automatizada pelo uso de moldes de compilação

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