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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

The use of computational fluid dynamics to simulate the flow in a high recirculation airlift reactor

de Souza, Althea Caroline January 2000 (has links)
No description available.
52

Um estudo sobre MDA: suporte fornecido pela UML e reuso de soluções pré-definidas. / A study on MDA: support provided by UML and reuse of pre-defined solutions.

José Eduardo Belix 07 April 2006 (has links)
Este trabalho tem por objetivo propor a utilização de soluções pré-definidas e comprovadas na abordagem MDA, auxiliando o desenvolvedor na resolução de problemas recorrentes ao desenvolvimento de software. A utilização destas soluções pré-definidas leva a um aumento de produtividade no contexto MDA e na geração de software baseado em boas práticas. Para que este objetivo seja cumprido, é empreendida uma análise sobre o MDA e sobre como operacionalizar as transformações entre modelos. Também é empreendida uma análise sobre o suporte fornecido pela UML e sobre reutilização em desenvolvimento orientado a modelos. Por fim este trabalho apresenta partes de uma aplicação protótipo, construída para ser uma prova de conceito de código gerado através da combinação de UML e soluções pré-definidas. / The goal of this work is to propose the use of pre-defined solutions on MDA approach, supporting the developer in solving recurrent problems of software development. The use of these pre-defined solutions leads to an increase of productivity in MDA context, and in the generation of software based on best practices. To reach this goal, an analysis of MDA is undertaken, as well as an analysis of how to enable the transformations between models. It is also undertaken an analysis about the use of UML and the reuse in model driven development. Finally this work presents portions of a prototype application, constructed to be a proof-of-concept of generated code, combining UML and the pre-defined solutions.
53

Ridge Coarsening in Evaporatively Driven Climbing Films

Lamb, Peter 01 May 2003 (has links)
In thin-film mixtures of alcohol and water, differences in evaporation rates and surface tensions between the two liquids can cause what is known as Marangoni convection within the fluid. This can lead to the formation of interesting instabilities on the surface of the film, such as the commonly observed “wine tears” phenomenon. Similar instabilities are observed when an inclined plate is immersed in a water alcohol reservoir. In addition to the tears, small ridges can be observed where the thin-film along the side of the plate rejoins the larger reservoir. These ridges slowly drift to the side and merge with other ridges, coarsening into larger ones. Using lubrication theory, Hosoi and Bush developed a one-dimensional model of the ridge instability which takes into account gravity, capillarity and Marangoni stresses at the surface of the film and results in a fourth-order non-linear partial differential equation describing the height of the ridges as a function of time and position along the plate. Two different but complementary numerical models were implemented to solve their equation. Both models are able to show development of ridges from random initial conditions as well as lateral ridge movement and coarsening. In addition to the numerical approaches some analysis was done on the equation to gain further insight into the nature of the ridge coarsening.
54

DATA DRIVEN WORKFORCE PERFORMANCE PLANNING

Barajas, Christopher 01 June 2019 (has links)
The business of logistics and transportation is increasing in demand and complexity and will do so into the future. As with many businesses in the digital age, large amounts of data is being generated at increasing speeds leading us all into the era of big data. A common result is that organizations are left data rich and information poor. At ABC Logistics, and many other third party logistics and transportation companies, the question is how to harness the data and create centers of excellence through business intelligence methodologies. This research project goes through the steps taken to identify an area where business intelligence and data transformation could be an advantageous prospect and how to present it in a way that would be of great benefit to the organization as a whole. Third party logistics companies, such as ABC Logistics, operate under a business model where they do not produce or own any of the product they manage through the supply chain process. What they sell is their expertise in logistics services from the inbound of product, processing of orders, and outbound shipping to and from the customer. This makes the third party logistics business very competitive. Competitive advantages are key to success in this type of business and one area that is underutilized is measuring and managing labor productivity. Currently, ABC Logistics utilizes an AS400 system for warehouse management and Kronos for timekeeping. The problem lies in how to get all the information together in one location where transactional master data is shared across the organization. Once we do that, then the second problem would be analysis and decision management i.e., how we analyze the data and present the information in a human readable format for frontline supervisors and middle management to be able to interpret the data and take action. The solution will be to create a data warehouse to normalize all the various data sources for timekeeping and warehouse production transactions. In order to build the data warehouse, we will utilize an SQL Database with SQL Server Integration Services to transform the data into our data warehouse. With the data transformed into a structured and consistent format, the data is analyzed and the results presented in a human readable format. This will be done through business intelligence tools such as Power BI that allows us to create custom dashboards. This solution will lead to a better understanding of our operation, increase profit, and give ABC Logistics a competitive advantage over their competitors.
55

Interprétations de la composition d'activités

Blay-Fornarino, Mireille 16 April 2009 (has links) (PDF)
Nos travaux de recherche portent sur la composition fiable d'activités logicielles. Ils s'inscrivent dans le cadre général du génie logiciel, et concernent les étapes de conception, implantation et adaptations d'applications logicielles réparties. Le thème central développé est la modélisation des activités et leur composition tout en garantissant différentes propriétés. La spécificité de ce travail et son originalité est d'avoir suivi une approche de la composition non pas dirigée par les langages mais par les éléments clefs de la composition indépendamment de mises en œuvres spécifiques. En fondant ce travail sur une approche formelle, nous proposons une vision unifiée d'un procédé de composition, et caractérisons les différences en terme d'interprétations. En étayant cette formalisation par plusieurs mises en œuvre à la fois en terme d'environnement de programmation et d'applications nous ancrons cette approche dans une réalité fonctionnelle. Les principales applications de ce travail portent sur la composition d'interactions entre composants hétérogènes et la composition de Workflows.
56

Double Ended Guillotine Break in a Prismatic Block VHTR Lower Plenum Air Ingress Scenario

Hartley, Jessica 2011 August 1900 (has links)
The double ended guillotine break leading to density-driven air ingress has been identified as a low probability yet high consequence event for Very High Temperature Reactor (VHTR). The lower plenum of the VHTR contains the core support structure and is composed of graphite. During an air ingress event, oxidation of the graphite structure under high temperature conditions in an oxygen containing environment could degrade the integrity of the core support structure. Following this large break, air from the reactor containment will begin to enter the lower plenum via two mechanisms: diffusion or density driven stratified flow. The large difference in time scales between the mechanisms leads to the need to perform high fidelity experimental studies to investigate the dominant the air ingress mechanism. A scaled test facility has been designed and built that allows the acquisition of velocity measurements during stratification after a pipe break. A non-intrusive optical measurement technique provides full-field velocity measurements profiles of the two species Particle Image Velocimetry (PIV). The data allow a more developed understanding of the fundamental flow features, the development of improved models, and possible mitigation strategies in such a scenario.Two brine-water experiments were conducted with different break locations. Flow fronts were analyzed and findings concluded that the flow has a constant speed through the pipe after the initial lock exchange. The time in which the flow enters the lower plenum is an important factor because it provides the window of opportunity for mitigation strategies in an actual reactor scenario. For both cases the flow of the heavier density liquid (simulating air ingress from the reactor containment) from the pipe enters the reactor vessel in under 6 seconds. The diffusion velocity and heavy flow front of the stratified flow layer were compared for the SF6/He gas case. It is seen that the diffusion plays less of a role as the transport mechanism in comparison to the density-driven stratified flow since the velocity of the diffusion is two orders of magnitude smaller than the velocity of the stratified flow mechanism. This is the reason for the need for density-driven stratified flow investigations following a LOCA. These investigations provided high-quality data for CFD validation in order for these models to depict the basic phenomena occurring in an air ingress scenario.
57

An Abstract Meta-model for Model Driven Development of Web Applications Targeting Multiple Platforms

Fatolahi, Ali 13 September 2012 (has links)
In this thesis, we present an abstract meta-model for model driven development of web applications targeting multiple platforms. We review the existing technologies and the related work in order to obtain a list of requirements for such an abstract model. The abstract model is built by extending an existing UML-based model for web applications. We demonstrate that it is possible to map this abstract model to more than one specific development platform by providing transformations for these mappings. We also lay out the general outline of a model-driven process based on the proposed abstract model. The abstract model and the model-driven process are supported by a set of tools, case studies and a visual modeling notation. Model-driven techniques have been used in the area of web development to a great extent. Most of the existing approaches are tuned toward specific platforms or develop only certain parts of web applications. These approaches generally use meta-models adapted to their targeted platforms. In order to flexibly target multiple platforms, the level of abstraction of the meta-model must be raised. Such a meta-model must allow the description of relevant features of web applications independently from the specificities of specific platforms. Additionally, transformations mapping from abstract to specific web descriptions must be expressible in a flexible way. In this thesis, we propose such an abstract meta-model. Mappings that transform abstract models to specific platforms are also presented. Different benefits can be foreseen from this approach. By relieving developers from low-level platform-specific related design, the approach has the potential to shift the development task to issues related to business needs. Another benefit is shortened development time. This could help web developers to overcome the problem of schedule delays, which is recognized as one of the top five most-cited problems with large-scale web systems. The approach is specifically suitable for information-intensive web-based systems. These applications typically involve large data stores accessed through a web interface. A distinctive aspect of this approach is its use of a specification of the data mapping as part of its high-level input. More importantly, the common features required to process data and communicate data objects between different layers and components are targeted.
58

A transcriptomic approach toward understanding PAMP-driven macrophage activation and dietary immunostimulation in fish

Doñate Jimeno, Carmen 18 December 2008 (has links)
Los peces son claramente el grupo más exitoso y diverso de vertebrados, representando el 40% de todas las especies de vertebrados y mostrando un impresionante nivel de diversidad en distintos aspectos biológicos. Exhiben un gran número de particularidades genómicas únicas entre los vertebrados, que presentan a los peces como un modelo muy interesante para diversas disciplinas, en particular aquellas relacionas con la evolución. Por estas razones, algunas especies de peces han tenido un papel muy importante en los últimos años en el incremento del conocimiento de la especialización del genoma en vertebrados. Por otra parte, tienen una importancia vital como comida, siendo la acuicultura un sector productor alimentario esencial en todo el mundo. El objetivo del presente trabajo ha sido caracterizar ciertos aspectos moleculares y funcionales del sistema inmune de dos especies distantes en la evolución, Sparus aurata (dorada) y Oncorhynchus mykiss (trucha arco iris), con especial énfasis en sus respuestas transcriptómicas a diferentes estímulos relativos a patógenos. Con esta finalidad, análisis in vivo e in vitro fueron combinados para evaluar mecanismos inmunitarios globales de estos teleósteos. Los Macrófagos representan un grupo importante de células que poseen un papel principal en la iniciación y coordinación de la respuesta inmune. Se desarrolló y caracterizó un cultivo primario de macrófagos diferenciados in vitro de dorada, investigando aspectos como morfología, capacidad fagocítica y respuesta a lipopolisacárido (LPS) de este tipo celular. En paralelo, CD83, una proteína de membrana utilizada como marcador estándar de células dendríticas en mamíferos fue clonada y analizada usando Q-PCR (PCR a tiempo real, cuantitativa). A continuación, los macrófagos diferenciados de dorada fueron comparados con los de trucha, evaluando sus diferencias en la activación de vías antivirales bajo la inducción de LPS y las implicaciones de la presencia de contaminantes en preparaciones comerciales de LPS. La expresión de varios genes antivirales fue cuantificada mediante Q-PCR. Para analizar más profundamente las respuestas inmunes de macrófagos, su regulación transcriptómica en respuesta a LPS bacteriano y Poly (I:C) viral fue estudiada utilizando una plataforma de microarray de cDNA enriquecida en genes con funciones inmunes, resultados que fueron posteriormente validados con Q-PCR, junto con el análisis mediante western blot de la liberación de la citoquina inflamatoria Factor de Necrosis Tumoral α (TNFα). Finalmente, la regulación de cortisol y la respuesta trancriptómica de los teleósteos a una modulación inmune fue evaluada a través de la administración de dietas inmunoestimulantes, que son comúnmente utilizadas en acuicultura. A través de diversos análisis, utilizando la plataforma de microarray, hibridaciones in situ y cuantificación de los niveles de cortisol en plasma por R.I.A., estudiamos respuestas específicas en tejidos (riñón anterior, bazo, intestino y branquias) en truchas alimentadas durante cuatro semanas con una dieta inmunoestimulante, en condicones basales y siguiendo una inducción con LPS. Los resultados obtenidos han sido presentados y discutidos en este trabajo. / Fish are by far the most successful and diverse group of vertebrates, representing 40% of all vertebrate species and displaying an amazing level of diversity in several biological aspects. They exhibit a number of genomic particularities unique among vertebrates that present fish as a very interesting model to gain an insight into a wide variety of disciplines, in particular those related to evolution. Therefore some fish species have played important roles in the latest years to increase the knowledge of vertebrate genome speciation. On the other hand, they are of tremendous importance as food for people, becoming the aquaculture industry an essential food-producing sector all around the world. The goal of the present study has been to characterize several molecular and functional aspects of the immune system of two evolutionary distant fish species, Sparus aurata (gilthead sea bream) and Oncorhynchus mykiss (rainbow trout), with specific emphasis on their transcriptomic responses to different pathogen-related challenges. To that end, in vivo and in vitro analyses were combined to evaluate global immune mechanisms of these teleosts.The macrophage cell lineage represents an important group of cells which play a central role in the initiation and coordination of the immune response. A primary culture of in vitro differentiated macrophages of gilthead sea bream was developed and characterized; therefore aspects as morphology, phagocytic capacity and response to lipopolysaccharides (LPS) of these cells were investigated. In parallel, CD83, a cell surface membrane used as standard surface marker for dendritic cells in mammals, was cloned and then analyzed from the gilthead sea bream macrophages using Q-PCR (real-time quantitative-PCR). Once this in vitro model was characterized and validated, differentiated macrophages of gilthead sea bream were compared with those of rainbow trout to evaluate their differences in the activation of antiviral-related pathways upon LPS induction and the implications of the presence of contaminants in commercial LPS preparations when analyzing regulation of gene expression. Expression of antiviral genes in macrophages stimulated with different LPS preparations were quantified with Q-PCR. To further address rainbow trout macrophages immune responses, their transcriptomic regulation in response to bacterial LPS and viral Poly I:C was studied using a salmonid-specific cDNA microarray platform enriched in immune-related genes and validated with Q-PCR, together with the analysis of the release of the pro-inflammatory cytokine tumor necrosis factor α (TNFα) by western blot. Finally, the cortisol regulation and transcriptomic response of teleost fish to immuno-modulation were investigated via the administration of immunostimulant diets, which are commonly utilized in aquaculture. Using the salmonid-specific microarray platform, in situ hybridizations and quantification of plasma cortisol levels by radioimmunoassay, we studied tissue specific (head kidney, spleen, intestine and gills) responses in rainbow trout fed for four weeks with a commercial immunostimulant diet, in a basal situation and following a challenge with LPS. The results obtained are presented and discussed in this report.
59

A framework for the analysis of failure behaviors in component-based model-driven development of dependable systems

Javed, Muhammad Atif, Faiz UL Muram, Faiz UL Muram January 2011 (has links)
Currently, the development of high-integrity embedded component-based software systems is not supported by well-integrated means allowing for quality evaluation and design support within a development process. Quality, especially dependability, is very important for such systems. The CHESS (Composition with Guarantees for High-integrity Embedded Software Components Assembly) project aims at providing a new systems development methodology to capture extra-functional concerns and extend Model Driven Engineering industrial practices and technology approaches to specifically address the architectural structure, the interactions and the behavior of system components while guaranteeing their correctness and the level of service at run time. The CHESS methodology is expected to be supported by a tool-set which consists of a set of plug-ins integrated within the Eclipse IDE. In the framework of the CHESS project, this thesis addresses the lack of well integrated means concerning quality evaluation and proposes an integrated framework to evaluate the dependability of high-integrity embedded systems. After a survey of various failure behavior analysis techniques, a specific technique, called Failure Propagation and Transformation Calculus (FPTC), is selected and a plug-in, called CHESS-FPTC, is developed within the CHESS tool-set. FPTC technique allows users to calculate the failure behavior of the system from the failure behavior of its building components. Therefore, to fully support FPTC, CHESS-FPTC plug-in allows users to model the failure behavior of the building components, perform the analysis automatically and get the analysis results back into their initial models. A case study about AAL2 Signaling Protocol is presented to illustrate and evaluate the CHESS-FPTC framework. / CHESS Project - http://chess-project.ning.com/
60

How to Perform Market Orientation in New Product Development

Hu, Hao, Xu, Chenke January 2011 (has links)
In  turbulent  environments,  the  infused  marketing  function  has  become  an  essential and natural part in the firms’ new product development (NPD). Some scholars define NPD as the transformation of a market opportunity into a product  as a result of the coupling of market assumptions with technological possibilities. The purpose of this thesis is to explore the role of market orientation in NPD, with the specific focus on how market orientation is carried out in NPD and how it affects NPD. This study is built  on  a  conceptual  framework  and  a  tool,  both  are  formed  from  literature.  The authors use the case study to conduct this research, and one company’s (Tylö’s) data is  gathered  through  the  semi-structured  interview.  Some  findings  are  obtained  from analysis: Firstly, market orientation contains two approaches, one is the market-driven approach and the other is the driving-market one, and firm could choose one of them according  to  the  new  product  features.  Secondly,  there  are  four  areas  in  market orientation, for each approach, the specific content in each area is different. Thirdly, the    four    areas    are    identifying    customers’    needs,    collecting    information, inter-functional  coordination  and  taking  action  and  they  move  on  sequentially.  In addition, two crucial factors-time and cost should be paid much attention in NPD.

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