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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

A process reuse identification framework using an alignment model

De Vries, Marne 14 August 2013 (has links)
This thesis explores the potential to unify three emerging disciplines: enterprise engineering, enterprise architecture and enterprise ontology. The current fragmentation that exists in literature on enterprise alignment and design constrains the development and growth of the emerging disciplines. Enterprises need to use a multi-disciplinary approach when they continuously align, design and re-design the enterprise. Although enterprises need to be aligned internally (across various enterprise facets), as well as externally (with the environment), most alignment approaches still focus on business-IT alignment, i.e. aligning the business operations with the information and communication technologies and systems of the enterprise. This study focuses on a popular business-IT alignment approach,called the foundation for execution approach, and its associated artefact, called the operating model. The study acknowledges the theoretical contribution of the operating model to establish the required level of business process integration and standardisation at an enterprise in delivering goods and services to customers. Highlighting the practical problems in selecting an operating model for an enterprise, and more specifically the practical problems of identifying process reuse potential at an enterprise, a thesis statement is formulated: The operating model concept, as part of a business-IT alignment approach, can be enhanced with a process reuse identification framework, when a business-IT alignment contextualisation is used. The study is divided into two research questions. The first research question addresses the current fragmentation that exists in the literature, which impairs reuse of the existing business-IT alignment knowledge base. An inductive literature review develops the Business-IT Alignment Model to provide a common contextualisation for current business-IT alignment approaches. The second research question addresses the practical problems of the operating model regarding the identification of process reuse potential at an enterprise. Applying the newly developed Business-IT Alignment Model as a contextualisation instrument, the study demonstrates the use of design research in developing the Process Reuse Identification Framework. The conclusion after the investigation of the two research questions is that the thesis statement was confirmed, i.e. the operating model concept, as part of a business-IT alignment approach, can be enhanced with a process reuse identification framework, when a business-IT contextualisation is used. / Thesis (PhD)--University of Pretoria, 2013. / Industrial and Systems Engineering / Unrestricted
52

The effect of carboxylic acids on the size and shape of Co3O4 nanoparticles: used as capping molecules and ligands in the preparation method

Thabede, P. M. 12 September 2017 (has links)
M.Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology / This study reports the synthesis and characterization of cobalt oxide nanoparticles using a microwave technique and chemical precipitation with oxidation method. Cobalt complexes were prepared using carboxylic acids (acetic acid, heptanoic acid, and stearic acid) as ligands. The complexes were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Elemental analyses (EA). Cobalt oxide nanoparticles were synthesized from the complexes via a microwave-assisted technique. A precipitation oxidation preparation reaction was used varying different parameters like pH, time, oxidising agent, heating method and cobalt precursor. The use of the cobalt nitrate and cobalt acetate as cobalt precursors resulted in spherical and cubic nanoparticles respectively. Cobalt precursors containing a longer hydrocarbon chain length, for instance cobalt heptanoate, did not yield cobalt oxide nanoparticles with the precipitation oxidation reaction due non- solubility of the complex. Using cobalt acetate as precursor, an increase in the pH from 7.91 to 10.18 caused the cobalt oxide nanoparticles shape to become well defined cubes with a narrower size range and CoOOH needles formed when the pH was further increased to 12.26. The optimum pH of 10.18 yielded cubic cobalt oxide particles having an average size of 25.45 nm with a standard deviation of 6.12. The nanoparticle size decreased from 35.70 nm to 4.45 nm when the oxygen oxidant was replaced with hydrogen peroxide. Conventional heating with a hotplate yielded nanoparticles with a more homogenous shape and size than microwave heating. The size of the nanoparticles increased from 22.81 nm to 25.45 nm when reaction time changed from 16 hours to72 hours.
53

Greffage radicalaire de polyoléfines sur les nanotubes de carbone multi-parois : l'étude modèle et l'application pour la fabrication de composites PE et PP / Radical grafting of polyolefins onto multi-walled carbon nanotubes : model study and application to manufacture PE & PP composites

Akbar, Sohaib 16 September 2010 (has links)
Les nanotubes de carbone (NTCs) sont des charges particulièrement intéressantes car ils présentent des facteurs de forme (longueur/diamètre) très élevés. Cependant, le développement de ces applications à haute valeur ajoutée a été freiné par les problèmes de mise en oeuvre des NTCs (résultant de la difficulté de les disperser dans un milieu polymère) et par la formation d’agrégats de nanotubes en « fagots », ne permettant pas l’obtention de mélanges homogènes. La solution réside dans la fonctionnalisation des nanotubes avec des chaînes polymères afin de réduire l’effet des interactions entre NTCs et d’assurer une meilleure comptabilisation avec le polymère hôte au cours du mélange. Ici, nous nous sommes intéressés à la fonctionnalisation des nanotubes de carbone par des polyoléfines en utilisant une procédure de greffage radicalaire de type « grafting onto ». / Carbon nanotubes (CNTs) as filler are particularly interesting because they possess very high aspect ratio (length/diameter), typically up to 10,000. Hence, they can form conductive path in polymer matrix at much lower concentrations (below 5%), whereas in case of carbon black filler more than 20wt% loading is needed. However, the development of applications based on nanotubes with high value addition has been hampered by processing limitations resulting from the difficulty of dispersing in a polymeric medium. The formation of aggregates or bundles of nanotubes into host polymer do not allow obtaining homogeneous mixtures. The solution lies in the functionalisation of nanotubes with polymer chains to reduce the effect of interactions between CNTs and better compatibility with the host polymer in the mixture. Here, in this study, we aim to functionalise carbon nanotubes by using a polyolefin grafting procedure involving radical ‘grafting onto’.
54

English Word Formation Processes: The use of affixations and implications for second language learning : A Case Study of Swedish Secondary Schools Grades 7-9

Håkansson, Jeannette January 2021 (has links)
This work explains the types of affixation errors second language learners make when learning English word formation processes, especially derivational and inflectional affixations. The data for the study were collected as primary sources from two secondary schools in Sweden. The data were analyzed with the use of Error Analysis noted by Corder (1967) and the error analysis framework adapted by Ellis et al. (2005, p. 57). The method chosen was to identify, classify, describe,and evaluate derivational and inflectional affixation errors. In total 2,812 answers were retrieved. The results consist of some findings, for example, some of the derivationaland inflectional affixations errors were noticed to be intralingual and interlingual. Also, the nature of the errors issuch that they are either transferred, omissive, additive or substitutive errors. Moreover, the errors were also due to overgeneralization, including substitutionerrors, or additive errors. Previous research findings showedstudents make grammatical errors with letter insertions, letter omission, or substitutionerrors. This study made the same findings as students made errors of letter insertion, letter omission, substitution errors, and errors due to overgeneralization. Some of the most difficult derivational and inflectional affixation errors were also noticed across all the grades.
55

Detecting Enterprise Architecture Smells based on Software Architecture Smells / Upptäcka verksamhetsrötor baserat på mjukvaruarkitekturrötor

Tieu, Benny January 2021 (has links)
Software architecture (SA) smells are design problems in the internal structure and behavior of an SA. These can be seen as a specific category under the umbrella concept of technical debt (TD). TD is a central concept in software development projects and having the means to detect and measure the smells is essential to understand impairments they may cause. However, TD is only limited to the technical aspects and does not describe smells found on an enterprise level. Enterprise architecture debt (EAD) expands the concepts of TD beyond the technical aspects such that it covers the debts that can be found in all layers of an Enterprise Architecture (EA). EA smells give a measurement for EAD by providing means for identifying and detecting the smell, hence enabling a method to quantify the level of debt. The goal of this thesis is to find EA smells derived from existing SA smells. In total, three new EA smells were presented based on existing SA smells. Each new smell was described by a short description that informally summarizes the smell. This was followed by an indication of the smell’s origin and reasoning about the effects on the quality. Then, an illustrative example of the smell was provided. Finally, a detection algorithm was also provided and implemented in a prototype detection program. This thesis serves as a basis for measurements of the quality of an EA and motivation for future research in this area. It is argued that the finding of EA smells can facilitate quality assessment in an EA. / Mjukvaruarkitektursrötor (MA-rötor) är designproblem i den interna strukturen och beteende i en mjukvaruarkitektur. Dessa kan ses som en specifik kategori under samlingsbegreppet teknisk skuld (TS). TS är ett centralt begrepp inom projekt i mjukvaruutveckling och att ha en metod att upptäcka och mäta dessa rötor är viktigt för att förstå försämringar dessa kan orsaka. TS är dock enbart avgränsat till de tekniska aspekterna och beskriver inte rötorna som kan finnas på en verksamhetsnivå. Verksamhetsarkitektursskulder (VAS) expanderar konceptet av TS utöver de tekniska aspekterna så att de även täcker skulderna som kan finnas på alla nivåer i en verksamhetsarkitektur (VA). VA-rötor ger ett mätvärde för VAS, genom att förse ett sätt att upptäcka rötorna och därmed möjliggöra ett sätt att kvantifiera graden av skuld. Målet i denna avhandling är att hitta VA-rötor som är härledda från befintliga MA-rötor. Totalt har tre nya VA-rötor presenterats baserat på befintliga MA-röter. Varje ny röta har beskrivits med en kort beskrivning som informellt summerar rötan. Detta följt av en indikation av rötans ursprung och resonemang om dess effekt på kvalitén. Ett illustrativt exempel har även presenterats. Slutligen, har en algoritm för att upptäcka rötan också presenterats och implementerats i ett prototypprogram för att upptäcka rötan. Denna avhandling används som en grund för mätvärden av kvalité i en VA och motivation för framtida studier i detta område. Det argumenteras för att identifieringen av VA-rötor kan förenkla kvalitetsbedömningen av en VA.
56

Biogeography-Based Optimization of a Variable Camshaft Timing System

Thomas, George L. January 2014 (has links)
No description available.
57

Optimization of Disaster Recovery Leveraging Enterprise Architecture Ontology

Manaktala, Rohit Sudhish 02 October 2013 (has links)
No description available.
58

Synthèse de copolymères greffés d'acétate de cellulose-g-PS par polymérisation radicalaire contrôlée par les nitroxydes / Synthesis of graft copolymers cellulose acetate-g-PS by Nitroxide-Mediated Polymerization

Moreira, Guillaume 19 June 2014 (has links)
Face à la diminution croissante des ressources d'origine fossile, une attention particulière est portée depuis plusieurs années envers l'utilisation de ressources renouvelables. Dans ce contexte, beaucoup de recherches sont orientées vers l'utilisation de polysaccharides tels que la cellulose. L'intérêt de ces composés est qu'ils sont abondants, peu chers et biodégradables. A l'inverse, ces polymères possèdent une faible résistance mécanique limitant ainsi leurs applications. De manière à moduler les propriétés de ces polymères, une alternative consiste à les modifier chimiquement par greffage de chaînes de polymères synthétiques. Néanmoins, les stratégies de greffage décrites dans la littérature présentent certaines limitations notamment sur la facilité de mise en oeuvre, la toxicité des méthodes employées, le nombre d'étapes de synthèses ou encore le contrôle des masses molaires. Par ailleurs, la caractérisation de ces architectures complexes reste délicate notamment pour prouver le greffage covalent des chaînes de polymère sur le polysaccharide. C'est précisément dans cet axe de recherche que s'insère ce sujet de thèse. Plus particulièrement, l'objectif principal consiste à mettre au point une méthode de greffage de l'acétate de cellulose robuste et facile à mettre en oeuvre, en vue d'une utilisation potentielle en tant que compatibilisant de mélange de polystyrène et d'acétate de cellulose. Afin d'atteindre cet objectif, notre stratégie a consisté à utiliser la polymérisation radicalaire contrôlée par les nitroxydes (NMP) où une attention particulière a été portée sur la caractérisation structurale des matériaux synthétisés (RMN du solide et DOSY, RPE, CES, DLS et DSC). / In order to respond to the fossil resources depletion, a particular attention was paid to the use of renewable resources since several years. In this context, many researches focus on the use of polysaccharides such as cellulose. These compounds are attractive because of their abundance, low cost and biodegradability. On the other hand, these polymers suffer from weak mechanical resistance limiting their practical applications. Grafting synthetic polymers chains on these natural polymers is an alternative to this problem. Nevertheless, grafting strategies described in the literature involve certain limitations such as the difficulty of implementation, the toxicity of the used methods, the great number of synthesis steps or the control of molar mass. Moreover, the characterization of these complex architectures remains delicate in order to prove the covalent grafting of chains on the polysaccharide. In line with this research context, the topic of this thesis concerns the development of a robust method for cellulose acetate polymer grafting. Moreover, the selected method has to be easy to implement, with a possible application as a compatibilizer for blending of polystyrene and cellulose acetate. In order to achieve this purpose, our strategy is based on the use of Nitroxide-Mediated Polymerization (NMP) where particular attention was paid to the structural characterization of synthesized materials (solid state NMR, DOSY NMR, ESR, SEC of grafts, DLS and DSC).
59

Identification of avian pathogenic E. coli (APEC) genes important for the colonization of the chicken lung and characterization of the novel ExPEC adhesin I

Antão, Esther-Maria 11 June 2010 (has links)
Aviäre pathogene E. coli (APEC) sind extraintestinale Pathogene, die beim Huhn systemische Infektionskrankheiten hervorrufen. Zur Identifizierung Gene, die an der Kolonisierung des Wirtes beteiligt sind, wurde ein Lungen-Infektionsmodell in 5 Wochen alten SPF Hühnern etabliert. In dem Modell wurden 1.800 mittels Signature-tagged-Mutagenese (STM) hergestellten Mutanten des APEC Stamms IMT5155 (O2:K1:H5; ST-Komplex 95) auf ihre Fähigkeit zur Kolonisierung getestet. Die Untersuchung führte zur Identifizierung Gene, einschließlich Adhäsin-, LPS- und Kapsel-bildenden Genen, sowie Genen mit putativer Funktion. Die STM-Analyse erlaubte zudem die Identifizierung eines zuvor nicht charakterisierten putativen Fimbrien-bildenden Adhäsins (Yqi). Das Genprodukt wurde vorläufig als ExPEC Adhäsin I (EA/I) bezeichnet. Eine Deletion des EA/I-Gens führte zu einer Reduzierung der Adhäsionsfähigkeit des Stammes IMT5155 in vitro und in vivo. Eine Komplementierung des EA/I-Gens in trans resultierte in einer Wiederherstellung des Adhäsions¬vermögens in vitro. Das EA/I-Protein (~39 kDa) wurde als Fusionsprotein in vitro exprimiert, und mittels SDS-PAGE und Western Blot nachgewiesen. Durch Überexpression des EA/I-Operons in dem Fimbrien-negativen E. coli-Stamm AAEC189 konnten mittels elektronenmikroskopischer Aufnahmen Fimbrien-bildende Strukturen auf der äußeren Membran dargestellt werden. Das Vorkommen des yqi in den untersuchten extraintestinal pathogenen E. coli (ExPEC), bei gleichzeitigem Fehlen in allen untersuchten intestinal pathogenen E. coli bestätigt die Bezeichnung ExPEC Adhäsin I. Die Prävalenz des EA/I-Gens war am stärksten assoziiert mit Stämmen der B2-Phylogenetische-Gruppe und des ST95-Komplexes des Multi-Lokus-Sequenz-Typisierungs (MLST)-Schemas. Sequenzanalysen ergaben zudem erste Hinweise auf eine positive Selektion des EA/I-Gens innerhalb dieses Komplexes. In der vorliegenden Arbeit gelang somit die Identifizierung und Charakterisierung des neuen ExPEC Adhäsin I. / The extraintestinal pathogen, avian pathogenic E. coli (APEC), known to cause systemic infections in chickens, is responsible for large economic losses in the poultry industry. To identify genes, involved adhesion and colonization, a lung colonization model of infection was established in 5-week old specific-pathogen free (SPF) chickens, and Signature-tagged mutagenesis (STM) was applied to this model by generating and screening a total of 1,800 mutants of an APEC strain IMT5155 (O2:K1:H5; ST complex 95). This led to the identification of new genes of interest, including adhesins, genes involved in capsule and LPS formation, and genes of putative function. Among the many genes identified was one coding for a novel APEC fimbrial adhesin (Yqi) not described for its role in APEC pathogenesis. Its gene product was temporarily designated ExPEC Adhesin I (EA/I). Deletion of the ExPEC adhesin I gene resulted in reduced colonization ability by APEC strain IMT5155 both in vitro and in vivo. Complementation of the adhesin gene restored its ability to colonize epithelial cells in vitro. The ExPEC adhesin I protein (~ 39 kDa) was expressed as a fusion protein in vitro as shown by SDS-PAGE and western blotting. Electron microscopy of an afimbriate strain E. coli AAEC189 over-expressed with the putative EA/I gene cluster revealed short fimbrial like appendages protruding out of the bacterial outer membrane. We observed that the adhesin coding gene yqi is prevalent among extraintestinal pathogenic E. coli (ExPEC) isolates and absent in all of the intestinal pathogenic E. coli strains tested, thereby validating the designation of the adhesin as ExPEC Adhesin I. In addition, prevalence of EA/I was most frequently associated with the E. coli phylogenetic group B2 and ST95 complex of the multi locus sequence typing (MLST) scheme, with evidence of a positive selection within this complex. This is the first report of the newly identified and functionally characterized ExPEC adhesin I.
60

Defining Thresholds for Enterprise Architecture Debt / Definiera gränsvärden för Enterprise Architecture Debt

Larsson, Malin January 2021 (has links)
A common challenge in organizations is a perception of that different languages are spoken among IT and other departments. Co-workers come from different background, have different knowledge base and sometimes even different objectives which can make an alignment more challenging. Enterprise Architecture (EA) can align IT investments with business directions and potentially solve issues regarding business-IT misalignments and bring value to organizations. Technical Debt (TD) is a well-established concept in software development and means that a solution that is “quick and dirty” is applied in order to earn time in short term and be able to provide a function in a system more quickly. This primitive implementation will at a later stage need to be corrected and rewritten, and the longer it takes, the more advanced, complex and time-consuming the correction will be. As EA has grown, major scientific and academic contributions have been developed. What is still missing is insight and ability to include a debt concept, which not only address TD but also business aspects. By adapting the TD concept in the EA domain, a new metaphor, providing a holistic perspective, has been proposed; Enterprise Architecture Debt (EAD). Up to the present debts for measuring EAD has been identified, but current research projects has not yet identified when a certain measure is to be considered of high or low quality. There is a need to develop a process for deriving such thresholds and identifying them. To be able to communicate the severity of an EAD to stakeholders, thresholds for EAD measures plays an important role. These thresholds will in the long term play a role in providing a tool for computer scientist working in organizations exploiting EA, and also contribute to current research within the field of IT-management and EA. By adopting a systematic process for defining expert driven thresholds a first version of a process for defining EAD thresholds could be presented and tested with domain experts. Five common opinions were detected, regarding the process, among the experts. The process could potentially facilitate useful communication and it was considered positive that it highlighted the context of the EAD. Also, that clearer process description and real-world EA model examples was needed, and that the moment of selecting membership function was unnecessary came up. Further, drivers for EAD thresholds and areas where it is perceived as important to have thresholds for EADs was a focus during the study. Cost and time, responsibility and engagement and context are perceived to be important drivers for EAD thresholds. While the business-it alignment and master data are seen as important areas. Also, context can play an important role when determine important areas. / En vanlig utmaning inom organisationer är uppfattningen av att olika språka talas på IT-avdelningen och övriga avdelningar. Medarbetare kommer från olika bakgrund, har olika kunskapsbas och ibland till och med olika mål, vilket kan göra fastställandet av riktning mer utmanande. Enterprise Architecture (EA) kan säkerställa att IT investeringar och affärs direktiv går i samma riktning och kan därmed potentiellt lösa problem i anslutning till IT och övrig affärsverksamhet som uppstått på grund av detta och skapa värde till organisationen. Teknisk skuld är ett väletablerat koncept inom mjukvaruutveckling och syftar till att enlösning som är ”quick and dirty” tillämpas för att vinna tid på kort sikt och kunna tillämpa en funktionalitet i ett system snabbare. Denna primitiva implementation kommer vid senare tillfälle behöva korrigeras och skrivas om. Ju längre tid det tar desto mer avancerad, komplex och tidskrävande kommer ändringen att bli. I takt med att EA har vuxit har stora vetenskapliga och akademiska bidrag utvecklats. Vad som fortfarande saknas är insikt och förmåga att inkludera ett skuldkoncept som inte bara adresserar tekniks skuld utan även affärsaspekter. Genom att introducera konceptet teknisk skult i EA domänen har en ny metafor, som tillhandahåller ett helhetsperspektiv, föreslagits; Enterprise Architecture Debt (EA Debt). Fram tills idag har skulder för att mäta EA Debt blivit identifierade, men aktuella forskningsprojekt har ännu inte identifierat när en viss EA Debt är hög eller låg. Det finns ett behov av att utveckla en process för att härleda sådana gränsvärden och identifiera dem. För att kunna kommunicera all varlighetsgraden för en EA Debt till intressenter kan gränsvärden för EA Debt spela en viktig roll. Dessa gränsvärden kommer på lång sikt spela en roll när det kommer till att tillhandahålla verktyg för datavetare som arbetar i organisationer som tillämpar EA, och också bidra till aktuell forskning inom IT-förvaltning och EA. Genom att anta en systematisk process för att definiera expertdrivna gränsvärden har en första version av en process för att definiera EA Debt-gränsvärden kunnat presenteras och testas med domän-experter. Fem vanliga uppfattningar, gällande processen, kunde uppräckas bland experterna. Processens skulle också potentiellt kunna främja användbar kommunikation och det ansågs positivt att den belysta och tog hänsyn till kontext gällande EA Debt. Att tydligare processbeskrivning och verklighetstrogna EA-modeller som exempel behövdes samt att momentet där medlemsfunktion skulle väljas var onödigt kom också upp. Vidare så fokuserade studien på drivkrafter för att ta fram gränsvärden för EA Debt och områden där uppfattningen är att detta är viktigt. Kostnad och tid, ansvar och engagemang och kontext är uppfattade som viktiga drivkrafter när det kommer till gränsvärden för EA skuld, medan inriktningen för IT och övrig affärsverksamhet och basdata ses som viktiga områden. Även kontexten kan ha en viktig roll när det kommer till att avgöra vilka områden som är viktiga.

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