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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

Modeling and Experimental Validation of a Rankine Cycle Based Exhaust WHR System for Heavy Duty Applications / Modellering och experimentell validering av ett Rankinecykelbaserat Waste Heat Recovery-system

Carlsson, Carin January 2012 (has links)
To increase the efficiency of the engine is one of the biggest challenges for heavy vehicles. One possible method is the Rankine based Waste Heat Recovery. Crucial for Rankine based Waste Heat Recovery is to model the temperature and the state of the working fluid. If the state of the working fluid is not determined, not only the efficiency of the system could be decreased, the components of thesystem might be damaged.A Simulink model based on the physical components in a system developed by Scania is proposed. The model for the complete system is validated against a reference model developed by Scania, and the component models are further validated against measurement data. The purpose of the model is to enable model based control, which is not possible with the reference model. The main focus on the thesis is to model the evaporation and condensation to determine state and temperature of the working fluid. The developed model is compared to a reference model with little differences for while stationary operating for both the components and the complete system. The developed model also follows the behavior from measurement data. The thesis shows that two phase modeling in Simulink is possible with models based on the physical components.
12

Organizational Commitment, Relationship Commitment and Their Association with Attachment Style and Locus of Control

McMahon, Brian 05 April 2007 (has links)
Organizational commitment (OC) is a psychological state that binds an employee to an organization, and the Three-Component Model of organizational commitment (Meyer and Allen, 1991) posits that employees bind with their organizations as a result of desire (affective commitment), need (continuance commitment) and obligation (normative commitment). Similarly, relationship commitment between two people also has been conceived as a psychological state (Rusbult and Buunk, 1993), and Arriaga and Agnew (2001) outlined affective, cognitive and conative components of the state. This exploratory study examined the similarities between these conceptually parallel commitment models by determining how the dimensions of the two types of commitment correlate with one another, attachment style (Bowlby 1969/1982) and locus of control (Rotter, 1966). Data collected from 171 working adults yield several noteworthy associations and suggest future directions of inquiry.
13

The Confirmation of Amabile¡¦s Component Model of Creativity and Consensual Assessment Technique: The Evidence of Children¡¦s Drawing

Lai, Chu-ching 13 September 2006 (has links)
Amabile defines creativity from ¡§product¡¨. In her opinion, the behavior of creativity is by the products of the relevant fields of expert's assessment, and develops ¡§consensual assessment technique (CAT)¡¨ as the way to measure creativity. And Amabile proposes ¡§component model of creativity¡¨. If individual wants to have the creative behavior, he must possess three components: ¡§expertise¡¨, ¡§creative-thinking skill¡¨, and ¡§ task motivation¡¨. The main purpose of this study was to confirm the Amabile¡¦s component model of creativity and consensual assessment technique. This study had collected 29 students of a fifth grade in primary school class, and amounted to 162 drawing products. There were 9 judges come from 3 art domain expert's groups, including that 3 judges come from university professor's group, 3 judges come from junior and elementary teacher's groups, and 3 judges come from painter's groups. Each judge used the inventory of consensual assessment to evaluate each product independently. And this study designed inventory to exam students in the same class in order to collect the data. According to the results of the research: ( a) It was high common consensus that all judges evaluate creativity ,( b) It was middle-to-low common consensus that each group evaluate creativity , (c) Creativity measures taken in different groups showed significant correlations, (d) It was high common consensus to evaluate the creativity of the specific theme works, (e) The correlation between expertise and creativity was significant, (f) The correlation between creative-thinking skill and creativity was significant, (g) The correlation between motivation and creativity was significant. According to the results of the study, it could provide some suggestions for education and relevant studies, and it offered the foundation of further following studies in academia.
14

Bridging Component Models and Integration problems

Gelber, Natan January 2006 (has links)
<p>Component based software engineering promotes the use of software component as a cor-</p><p>ner stone for new software. Taken from other manufacturing fields, the vision of selecting</p><p>the components needed and building them as Lego to create a new software seems to of-</p><p>fer enormous advantages for software development. Worldwide, industry and scholars are</p><p>trying to remove the obstacles obstructing this course of action. This report names some</p><p>of the problems that software integrators and developers face. It concentrates on low-level</p><p>communication and other aspects of integration problems. it is based upon practical and</p><p>theoretical research. the conclusion of the report is that while each problem can be solved</p><p>in and of itself, these solutions often lead to the creation of new problems, and therefore</p><p>leave ample room for further research.</p>
15

Komponentinio modelio taikymas gamybos apskaitos sistemos projektavime / Implementation of the component model for design of production accounting system

Petrošiūtė, Martyna 16 August 2007 (has links)
Šiame darbe ištirta ir patikslinta komponentnio modelio taikymo informacinės sistemos projektavime technologija. Esamos veiklos modelio transformavimo taisyklės papildytos naujomis taisyklėmis. Komponentinis modelis palygintas su kitu reikalavimų specifikacijos modeliu (UML notacijos Use Case modeliu) ir nustatyta, kad komponentinis modelis labiau detalizuoja architektūrinį sistemos aprašymą. Eksperimentiškai įrodyta, kad komponentinio sistemos modelio (informacinės sistemos architektūros projekto) komponentai atitinka sukurtos gamybos apskaitos sistemos programinės įrangos komponentus ir duomenų bazės objektus. / In this work was detail analysed component model and implemented for design of production accounting system. For the formation component model was appended new rules to the existing rules. Component model was compared with use case model and found, that component model is more detailed, than use case model. After detail analyse was found, that components of component model matches components of developed system and objects of database.
16

Modeling and Timing Analysis of Industrial Component-Based Distributed Real-time Embedded Systems

Mubeen, Saad January 2012 (has links)
The model- and component-based development approach has emerged as an attractive option for the development of Distributed Real-time Embedded (DRE) systems. In this thesis we target several issues such as modeling of legacy communication, extraction of end-to-end timing models and support for holistic response-time analysis of industrial component-based DRE systems. We introduce a new approach for modeling legacy network communication in component-based DRE systems. By introducing special-purpose components to encapsulate and abstract the communication protocols in DRE systems, we allow the use of legacy nodes and legacy protocols in a component- and model-based software engineering environment. The proposed approach also supports the state-of-the-practice development of component-based DRE systems. The Controller Area Network (CAN) is one of the widely used real-time networks in DRE systems especially in automotive domain. We identify that the existing analysis of CAN does not support common message transmission patterns which are implemented by some high-level protocols used in the industry. Consequently, we extend the existing analysis to facilitate the worst-case response-time computation of these transmission patterns. The extended analysis is generally applicable to any high-level protocol for CAN that uses periodic, sporadic, or both periodic and sporadic transmission of messages. Because an end-to-end timing model should be available to perform the holistic response-time analysis, we present a method to extract the end-to-end timing models from component-based DRE systems. In order to show the applicability of our modeling techniques and extended analysis, we provide a proof of concept by extending the existing industrial component model (Rubus Component Model), implementing the holistic response-time analysis along with the extended analysis of CAN in the industrial tool suite (Rubus-ICE), and conducting an automotive case study. / EEMDEF
17

Multi-aspect component models: enabling the reuse of engineering analysis models in SysML

Jobe, Jonathan Michael 10 July 2008 (has links)
Today s market is driven by the desire for increasingly complex products that perform well from manufacturing to disposal. Designing these products for multiple lifecycle phases requires effective management of engineering knowledge and integration of this knowledge across multiple disciplines. By managing this knowledge, products can be realized faster, perform better and be more complex. However, management techniques are often very costly and managers can easily become bogged down with large quantities of information, slowing the design process and degrading knowledge transfer. Thus, a need exists for effective yet inexpensive knowledge management. One approach for decreasing the costs associated with generating design knowledge is to reuse modules of existing knowledge. In Model-Based Systems Engineering (MBSE), information about a design is stored formally in many knowledge structures, or models, including requirements, stakeholders, and analyses. To support the reuse of the existing knowledge in design, MBSE is used as a basis for integrating engineering analysis models. In this thesis, a framework is presented for model classification that organizes models by components and aspects. This scheme is found to be useful in classifying engineering analysis models for reuse by storing them as a set in containers known as Multi-Aspect Component Models (MAsCoMs). Each model in a MAsCoM is related to the formal structure model of a physical component, and to the many aspects of the component that the model represents. The Systems Modeling Language, OMG SysML, is used to implement MAsCoMs and support MBSE. Validation of the MAsCoM concept is performed with fluid-power design examples, including a log splitter, scissor lift, and hydraulic excavator. In these examples, MAsCoMs improve design value by 1) Classifying modular and composable engineering analysis models for reuse in multiple disciplines, and 2) Providing knowledge modules to computer-automated algorithms for the future automated composition of component models into system models to perform system-level analyses.
18

Dynamické Softwarové Architektury pro Resilientní Distribuované Systémy / Dynamic Software Architectures for Resilient Distributed Systems

Keznikl, Jaroslav January 2014 (has links)
Resilient Distributed Systems (RDS) are large-scale distributed systems that remain de-pendable despite their very dynamic, open-ended, and inherently unpredictable environ-ments. This combination of system and environment properties makes development of soft-ware architectures for RDS using contemporary architecture models and abstractions very challenging. Therefore, the thesis proposes: (1) new architecture abstractions that are tailored for building dynamic software architectures for RDS, (2) design models and processes that endorse these abstractions at design time, and (3) means for efficient implementation, execu-tion, and analysis of architectures based on these abstractions. Specifically, the thesis delivers (1) by introducing the DEECo component model, based on the concept of component ensembles. Contributing to (2), the thesis presents the Invari-ant Refinement Method, governing dependable, formally-grounded design of DEECo-based architectures, and the ARCAS method, focusing on dependable realization of open-ended dynamic component bindings typical for DEECo. Furthermore, it pursues (3) by presenting a formal operational semantics of DEECo and its mapping to Java in terms of an execution environment prototype - jDEECo. Additionally, the semantics is used as a basis for formal analysis via model...
19

Vytvoření a validace výpočtového FEM modelu kliky dveří pro crashové výpočty / Car Door Handle FEM Model Creation and Validation for Crash Simulations

Raffai, Peter January 2012 (has links)
The aim of this master’s thesis was to create a component model of a door handle stiffener used by the Volkswagen concern, which can be used for crash computations. Also to tune its parameters the way, its behavior corresponds the most to the real part’s. In the theoretical part the current regulations of the Euro NCAP are presented, concerning the testing and evaluation of the passive safety of new vehicles. Attention is focused on the evaluation of the side impact barrier tests, where the effect of the door handle stiffener’s damage is reflected the most. Shown are the reasons for the effort to simulate the real behavior of the stiffener, the factors, which initialized the born of the studied problem. The practical part starts with the creation of the FEM mesh of the part based on its 3D CAD model, also describes the requirements for the mesh quality, as well as the used tools and methods. Further on investigated are the characters of real damages of the door handle area during side impacts, based on which the component tests are proposed for the validation of the simulation model. Experimental research consists of the stiffener’s testing for simple bend and twist loads, three specimens each. After the execution of the tests the results get compared with the corresponding simulations. Modifications are made on the model according to the acquired results: refinement of the FEM mesh, new material model usage with failure for shell elements and definition of real material characteristics for the used thermoplastics. The latest obtained simulation dependencies are compared with the measured values again, the results are evaluated at last.
20

Modèle à Composant pour Plate-forme Autonomique / Component model for Autonomic-Ready plateform

Bourret, Pierre 24 October 2014 (has links)
Ces dernières décennies, les environnements informatiques sont devenus de plus en plus complexes, parsemés de dispositifs miniatures et sophistiqués gérant la mobilité et communiquant sans fil. L'informatique ubiquitaire, telle qu'imaginée par Mark Weiser en 1991, favorise l'intégration transparente de ces environnements avec le monde réel pour offrir de nouveaux types d'applications. La conception de programmes pour environnements ubiquitaires soulève cependant de nombreux défis, en particulier le problème de rendre une application auto-adaptable dans un contexte en constante évolution. Parallèlement, alors que la taille et la complexité de systèmes plus classiques ont explosé, IBM a proposé le concept d'informatique autonomique afin de réduire le fardeau de l'administration de systèmes imposants et largement disséminés. Cette thèse se base sur une approche où les applications sont conçues sous la forme de composants utilisant et fournissant des services. Un modèle de développement fondé sur une architecture de référence pour la conception d'applications ubiquitaires est proposée, fortement inspiré des recherches dans le domaine de l'informatique autonomique. Dans ce modèle, les applications sont prises en charge par une hiérarchie de gestionnaires autonomiques, qui appuient leurs décisions sur une représentation centrale du système. La mise en œuvre de cette contribution requiert de rendre la couche d'exécution sous-jacente plus réflexive, en vue de supporter de nouveaux types d'adaptations à l'exécution. Nous proposons également un modèle qui décrit le système à l'exécution et reflète sa dynamique de manière uniforme, suivant les principes du style d'architecture REST. Les applications reposant sur ce cette couche d'exécution réflexive et représentées par ce modèle sont qualifiées d'Autonomic-Ready. L'implantation de nos propositions ont été intégrées dans le modèle à composant orienté service Apache Felix iPOJO. Le modèle de représentation du système, nommé Everest, est publié en tant que sous-projet d'OW2 Chameleon. Ces propositions ont été évaluées et validées par la conception et l'exécution d'une application ubiquitaire sur iCASA, un environnement de développement et de simulation. / In the last decades, computing environments have been getting more and more complex, filled with miniaturized and sophisticated devices that can handle mobility and wireless communications. Ubiquitous computing, as envisioned by Mark Weiser in 1991, promote the seamless integration of those computing environments with the real world in order to offer new kinds of applications. However, writing software for ubiquitous environments raises numerous challenges, mainly the problem of how to make an application adapt itself in an ever changing context. From another perspective, as classical softwares were growing in size and complexity, IBM proposed the concept of autonomic computing to help to contain the burden of administering massive and numerous systems. This PhD thesis is based on an approach where applications are designed in terms of components using and providing services. A development model based on a reference architecture for the conception of ubiquitous applications is proposed, greatly inspired by researches in the autonomic computing field. In this model, the application is managed by a hierarchy of autonomic managers, that base their decisions on a central representation of the system. The fulfilment of this contribution requires to make the underlying middleware more reflexive, in order to support new kinds of runtime adaptations. We also provide a model that depicts the running system and its dynamics in a uniform way, based on REST principles. Applications relying on this reflexive middleware and represented by this model are what we called Autonomic-Ready. Implementations of our proposals have been integrated in the Apache Felix iPOJO service-oriented component model. The system representation, named Everest, is provided as a OW2 Chameleon subproject. Validation is based on the iCASA pervasive environment development and simulation environment.

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