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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.
1

METADATA FOR RANGE TELEMETRY

Grace, Thomas, Fink, Clay 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / CTEIP has launched the integrated Network Enhanced Telemetry (iNET) project to foster advances in networking and telemetry technology to meet emerging needs of major test programs. This paper describes an approach for providing a unified means of describing telemetry systems. It will describe the motivation and framework for a metadata standard for specifying the components of an instrumented test article, its data and the flow of data through a telemetry system. The paper will also describe how this metadata standard can provide the means for describing different transmission formats for a common test article. The result of the task described by this paper will lead to a standard or set of standards that will optimize the use of commercial technology and tools.
2

An Interface-based Modular Approach for Designing Distributed Event-based Systems

Wang, Jun 23 April 2008 (has links)
A Distributed Event-based System (DEBS) exhibits its desired behavior through its functional components collaborating with each other via event exchanging. Due to loose-coupling and flexibility, DEBS applications have become increasingly popular. Indeed, such systems are expected to appear in various application domains such as large-scale Internet applications and ubiquitous computing. Notwithstanding their popularity, current DEBS applications are still often developed in an informal process and are not modularized. On the individual event level, current DEBS developers can define what events a component can accept and publish, and, by registering event handlers, what action an event can trigger. Currently, developers lack structuring mechanisms for representing event interactions and dependencies in a modular way. While current research has made fruitful contributions to various aspects in the DEBS paradigm, such as, event delivery, event detection and composition, event visibility, its emphasis is on the individual event level. In this thesis, we advocate that by designing a new DEBS metamodel with extended behavioral interfaces and high-level structure mechanisms, we can (1) define an interface-based modular approach to model and design DEBS applications, (2) implement a prototype framework on a P2P network that provides built-in support to our proposed interface-based DEBS development, and (3) provide case studies illustrating the interface-based development process and the applicability of our proposed approach.
3

An Interface-based Modular Approach for Designing Distributed Event-based Systems

Wang, Jun 23 April 2008 (has links)
A Distributed Event-based System (DEBS) exhibits its desired behavior through its functional components collaborating with each other via event exchanging. Due to loose-coupling and flexibility, DEBS applications have become increasingly popular. Indeed, such systems are expected to appear in various application domains such as large-scale Internet applications and ubiquitous computing. Notwithstanding their popularity, current DEBS applications are still often developed in an informal process and are not modularized. On the individual event level, current DEBS developers can define what events a component can accept and publish, and, by registering event handlers, what action an event can trigger. Currently, developers lack structuring mechanisms for representing event interactions and dependencies in a modular way. While current research has made fruitful contributions to various aspects in the DEBS paradigm, such as, event delivery, event detection and composition, event visibility, its emphasis is on the individual event level. In this thesis, we advocate that by designing a new DEBS metamodel with extended behavioral interfaces and high-level structure mechanisms, we can (1) define an interface-based modular approach to model and design DEBS applications, (2) implement a prototype framework on a P2P network that provides built-in support to our proposed interface-based DEBS development, and (3) provide case studies illustrating the interface-based development process and the applicability of our proposed approach.
4

A Methodology for Transformation from Sequence Diagram to Class Diagram

Hsu, Chih-Tung 15 June 2006 (has links)
Today, modeling the software with unified modeling language (UML) and computer-aided software engineering (CASE) tool becomes the main stream for the objected-oriented systems analysis and design. To enhance the degree of ransformation automation and reuse in the system development process, prior research suggested that most parts of the class diagram can be transformed from the sequence diagram directly. However, the explicit guideline for the transformation is lacking. This study presents a methodology, extended from Selonen et al (2003), to transform the sequence diagram into the class diagram. A real-world case using the integrated techniques is presented to illustrate the concepts, application, and the advantages of using the proposed approach. With this approach, the system developer can transform most parts of the sequence diagram into its associated class diagram automatically and thereby enhance the efficiency of system development.
5

Simulation of power distribution management system using OMACS metamodel

Manghat, Jaidev January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Scott A. DeLoach / Designing and implementing large, complex and distributed systems using semi-autonomous agents that can reorganize and adapt themselves by cooperating with one another represents the future of software systems. This project concentrates on analyzing, designing and simulating such a system using the Organization Model for Adaptive Computational Systems (OMACS) metamodel. OMACS provides a framework for developing multiagent based systems that can adapt themselves to changes in the environment. Design of OMACS ensures the system will be highly robust and adaptive. In this project, we implement a simulator that models the adaptability of agents in a Power Distribution Management (PDM) system. The project specifies a top-down approach to break down the goals of the PDM system and to design the functional role of each agent involved in the system. It defines the different roles in the organization and the various capabilities possessed by the agents. All the assignments in PDM system are based on these factors. The project gives two different approaches for assigning the agents to the goals they are capable of achieving. It also analyzes the time complexity and the efficiency of agent assignments in various scenarios to understand the effectiveness of agent reorganization.
6

The influence of mooring dynamics on the performance of self reacting point absorbers

Ortiz, Juan Pablo 08 June 2016 (has links)
The design of a mooring system for a floating structure is a significant challenge; the choice of line structure and layout determine highly non-linear hydrodynamic behaviors that, in turn, influence the dynamics of the whole system. The difficulty is particularly acute for Self-Reacting Point Absorber Wave Energy Converters (SRPA WEC) as these machines rely on their movements to extract useful power from wave motions and the mooring must constrain the SRPA WEC motion without detracting from power production. In this thesis this topic has been addressed in an innovative way and new ideas on how these devices should be moored were investigated. As part of the study, an optimization routine was implemented to investigate the optimal mooring design and its characteristics. In this process, different challenges were faced. To evaluate the different mooring configurations, a high fidelity representation of the system hydrodynamics is necessary which captures the non-linearities of the system. Unfortunately, high-fidelity modeling tends to be very computationally expensive, and for this reason previous studies based mooring design largely relies on simplified representations that only reflect part of the mooring design space since some physical and hydrodynamic properties are dropped. In this work, we present how a full hydrodynamic time domain simulation can be utilized within a Metamodel-Based Optimization to better evaluate a wider range of mooring configurations spanning the breadth of the full design space. The method uses a Metamodel, defined in terms of the mooring physical parameters, to cover the majority of the optimization process a high fidelity model is used to establish the Metamodel in a pre-processing stage. The method was applied to a case study of a two-body heaving SRPA WEC. Survivability constrains where introduce into the model using a new statistical approach which reduces the execution time, and allowed the optimization routine. The analysis results lead to the conclusion that for SRPA WEC the mooring loads have a significant impact on how the body reacts with the waves, affecting both the energy that enter the system as well as the energy that is extracted as power. This implies that, in some cases, the mooring lines need to be considered in early stages of the designs as opposed to an afterthought, as is typically done. Results indicate that an optimal mooring design can result in a 26% increase in total annual power production. In addition, the mooring lines impact on mitigating parasitic pitch and roll were analyzed. It was established that in regular waves, the mooring lines can reduce the parametric excitations and improve the power extraction up to 56% for a particular sea state. By applying a computationally efficient iterative design approach to a device's mooring, parasitic motions and suboptimal device operation can be reduced, ultimately making WECs a more competitive source of energy. / Graduate / 0346 / 0537 / 0548 / 0547 / jortiz@uvic.ca
7

Multi-Agent systems and organizations / Multi-Agent systems and organizations

Kúdela, Lukáš January 2012 (has links)
Multi-agent systems (MAS) are emerging as a promising paradigm for conceptualizing, designing and implementing large-scale heterogeneous software systems. The key advantage of looking at components in such systems as autonomous agents is that as agents they are capable of flexible self-organization, instead of being rigidly organized by the system's architect. However, self-organization is like evolution-it takes a lot of time and the results are not guaranteed. More often than not, the system's architect has an idea about how the agents should organize themselves-what types of organizations they should form. In our work, we tried to solve the problem of modelling organizations and their roles in a MAS, independent of the particular agent platform on which the MAS will eventually run. First and foremost, we have proposed a metamodel for expressing platform-independent organization models. Furthermore, we have implemented the proposed metamodel for the Jade agent platform as a module extending this framework. Finally, we have demonstrated the use of our module by modelling three specific organizations: remote function invocation, arithmetic expression evaluation and sealed-bid auction. Our work shows how to separate the behaviour acquired through a role from the behaviour intrinsic to an agent. This...
8

De la modélisation objet des logiciels à la metamodélisation des langages informatiques

Muller, Pierre-Alain 20 November 2006 (has links) (PDF)
Mes travaux concernent la modélisation opérationnelle des systèmes à informatique prépondérante, dans le double but de capitaliser les savoir-faire et d'automatiser les réalisations. La modélisation est l'utilisation d'une représentation, en lieu et place d'une chose du monde réel, dans un but cognitif. Un modèle se substitue à un système dans un contexte donné, à moindre coût, plus simplement, plus rapidement et sans les risques ou dangers inhérents à une manipulation du système réel. Une modélisation devient opérationnelle dès lors qu'une implantation informatique peut en être dérivée de manière systématique. L'ensemble de mes travaux a pour but in fine de réduire le fossé entre les processus métier et les techniques d'informatisation. Je m'intéresse à la fois à la formalisation des savoir-faire métier et informatique. Ma démarche scientifique mélange des aspects théoriques et des validations expérimentales. Elle procède par fertilisation croisée, en reposant tout à la fois sur l'analyse de l'état de l'art, la participation à des groupes de travail ou de normalisation, et à la confrontation avec des problématiques industrielles. Les idées que j'ai approfondies dans mes travaux ont émergées dans différentes communautés (telles celles des grammaires, des bases de données, de la gestion des documents, des méthodes formelles...). Je procède en considérant la modélisation comme une alternative à la programmation. C'est une posture certes un peu radicale – car la modélisation et la programmation peuvent très bien se complémenter – mais je l'ai choisi afin d'amener les techniques de modélisation à leur extrême. Mes principales contributions portent sur : - Des avancées méthodologiques, dans le domaine de la modélisation objet avec UML et aussi dans l'intégration entre l'ingénierie dirigée par les modèles et les méthodes agiles. Ces contributions ont été validées dans des contextes industriels, en collaboration avec Rational Software et ObjeXion Software. - Des contributions pour la capitalisation du savoir-faire de modélisation des systèmes de commande et contrôle. Ces travaux à la frontière entre l'informatique et l'automatique, ont été réalisés en partenariat avec l'Ifremer et Nipson Printing System. - Des contributions pour la modélisation opérationnelle des systèmes d'information Web. Ces contributions s'inscrivent dans le cadre d'un transfert de technologie, sous la forme d'une création d'entreprise innovante : ObjeXion Software. - Des contributions pour l'application de la modélisation à l'ingénierie des langages. Ces travaux regroupés dans le projet open-source Kermeta porté par l'INRIA, font l'objet d'un déploiement industriel dans le cœur de la plateforme RNTL OpenEmbeDD.
9

Probabilistic Robust Design For Dynamic Systems Using Metamodelling

Seecharan, Turuna Saraswati January 2007 (has links)
Designers use simulations to observe the behaviour of a system and to make design decisions to improve dynamic performance. However, for complex dynamic systems, these simulations are often time-consuming and, for robust design purposes, numerous simulations are required as a range of design variables is investigated. Furthermore, the optimum set is desired to meet specifications at particular instances in time. In this thesis, the dynamic response of a system is broken into discrete time instances and recorded into a matrix. Each column of this matrix corresponds to a discrete time instance and each row corresponds to the response at a particular design variable set. Singular Value Decomposition (SVD) is then used to separate this matrix into two matrices: one that consists of information in parameter-space and the other containing information in time-space. Metamodels are then used to efficiently and accurately calculate the response at some arbitrary set of design variables at any time. This efficiency is especially useful in Monte Carlo simulation where the responses are required at a very large sample of design variable sets. This work is then extended where the normalized sensitivities along with the first and second moments of the response are required at specific times. Later, the procedure of calculating the metamodel at specific times and how this metamodel is used in parameter design or integrated design for finding the optimum parameters given specifications at specific time steps is shown. In conclusion, this research shows that SVD and metamodelling can be used to apply probabilistic robust design tools where specifications at certain times are required for the optimum performance of a system.
10

Probabilistic Robust Design For Dynamic Systems Using Metamodelling

Seecharan, Turuna Saraswati January 2007 (has links)
Designers use simulations to observe the behaviour of a system and to make design decisions to improve dynamic performance. However, for complex dynamic systems, these simulations are often time-consuming and, for robust design purposes, numerous simulations are required as a range of design variables is investigated. Furthermore, the optimum set is desired to meet specifications at particular instances in time. In this thesis, the dynamic response of a system is broken into discrete time instances and recorded into a matrix. Each column of this matrix corresponds to a discrete time instance and each row corresponds to the response at a particular design variable set. Singular Value Decomposition (SVD) is then used to separate this matrix into two matrices: one that consists of information in parameter-space and the other containing information in time-space. Metamodels are then used to efficiently and accurately calculate the response at some arbitrary set of design variables at any time. This efficiency is especially useful in Monte Carlo simulation where the responses are required at a very large sample of design variable sets. This work is then extended where the normalized sensitivities along with the first and second moments of the response are required at specific times. Later, the procedure of calculating the metamodel at specific times and how this metamodel is used in parameter design or integrated design for finding the optimum parameters given specifications at specific time steps is shown. In conclusion, this research shows that SVD and metamodelling can be used to apply probabilistic robust design tools where specifications at certain times are required for the optimum performance of a system.

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