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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

Model Based Aircraft Control System Design and Simulation

M Venkata, Raghu Chaitanya January 2009 (has links)
Development of modern aircraft has become more and more expensive and time consuming. In order to minimize the development cost, an improvement of the conceptual design phase is needed. The desired goal of the project is to enhance the functionality of an in house produced framework conducted at the department of machine design, consisting of parametric models representing a large variety of aircraft concepts. The first part of the work consists of the construction of geometric aircraft control surfaces such as flaps, aileron, rudder and elevator parametrically in CATIA V5. The second part of the work involves designing and simulating an Inverse dynamic model in Dymola software. An Excel interface has been developed between CATIA and Dymola. Parameters can be varied in the interface as per user specification; these values are sent to CATIA or Dymola and vice versa. The constructed concept model of control surfaces has been tested for different aircraft shapes and layout. The simulation has been done in Dymola for the control surfaces.
12

Multi-layer syntactical model transformation for model based systems engineering

Kwon, Ky-Sang 03 November 2011 (has links)
This dissertation develops a new model transformation approach that supports engineering model integration, which is essential to support contemporary interdisciplinary system design processes. We extend traditional model transformation, which has been primarily used for software engineering, to enable model-based systems engineering (MBSE) so that the model transformation can handle more general engineering models. We identify two issues that arise when applying the traditional model transformation to general engineering modeling domains. The first is instance data integration: the traditional model transformation theory does not deal with instance data, which is essential for executing engineering models in engineering tools. The second is syntactical inconsistency: various engineering tools represent engineering models in a proprietary syntax. However, the traditional model transformation cannot handle this syntactic diversity. In order to address these two issues, we propose a new multi-layer syntactical model transformation approach. For the instance integration issue, this approach generates model transformation rules for instance data from the result of a model transformation that is developed for user model integration, which is the normal purpose of traditional model transformation. For the syntactical inconsistency issue, we introduce the concept of the complete meta-model for defining how to represent a model syntactically as well as semantically. Our approach addresses the syntactical inconsistency issue by generating necessary complete meta-models using a special type of model transformation.
13

Aircraft Parametric 3D Modelling and Panel Code of Analysis for Conceptual Design

Tarkian, Mehdi, Javier Zaldivar Tessier, Francisco January 2007 (has links)
<p>Throughout the development of this report there will be a brief explanation of what the actual Aircraft Design Process is and in which stages the methodology that the authors are proposing will be implemented as well as the tools that will interact to produce this methodology.</p><p>The proposed tool will be the first part of a methodology that, according to the authors, by integrating separate tools that are currently used in different stages of the aeronautical design, will promote a decrease in the time frame for the initial stages of the design process.</p><p>The first part of the methodology above, that is proposed in this project, starts by creating a computer generated aircraft model and analyzing its basic aerodynamic characteristics “Lift Coefficient” and “Induced Drag Coefficient”, this step will be an alternative to statistical and empirical methods used in the industry, which require vast amount of data.</p><p>This task will be done in several steps, which will transfer the parametric aircraft model to an input file for the aerodynamic analysis program. To transfer the data a “translation” program has been developed that arranges the geometry and prepares the input file for analysis.</p><p>During the course of this report the reader will find references to existing aircrafts, such as the MD-11 or Airbus 310. However, these references are not intended to be an exact computer model of the mentioned airplanes. The authors are using this as reference so the reader can relate what he/she is seeing in this paper to existing aircrafts. By doing such comparison, the author intends to demonstrate that the Parametric Model that has been created possesses the capability to simulate to some extend the shape of existing aircrafts.</p><p>Finally from the results of this project it is concluded that the methodology in question is promising. Linking the two programs is possible and the aerodynamic characteristics of the models tested fall in the appropriate range. None the less the research must continue following the line that has been discussed in this report.</p>
14

Aircraft Parametric 3D Modelling and Panel Code of Analysis for Conceptual Design

Tarkian, Mehdi, Javier Zaldivar Tessier, Francisco January 2007 (has links)
Throughout the development of this report there will be a brief explanation of what the actual Aircraft Design Process is and in which stages the methodology that the authors are proposing will be implemented as well as the tools that will interact to produce this methodology. The proposed tool will be the first part of a methodology that, according to the authors, by integrating separate tools that are currently used in different stages of the aeronautical design, will promote a decrease in the time frame for the initial stages of the design process. The first part of the methodology above, that is proposed in this project, starts by creating a computer generated aircraft model and analyzing its basic aerodynamic characteristics “Lift Coefficient” and “Induced Drag Coefficient”, this step will be an alternative to statistical and empirical methods used in the industry, which require vast amount of data. This task will be done in several steps, which will transfer the parametric aircraft model to an input file for the aerodynamic analysis program. To transfer the data a “translation” program has been developed that arranges the geometry and prepares the input file for analysis. During the course of this report the reader will find references to existing aircrafts, such as the MD-11 or Airbus 310. However, these references are not intended to be an exact computer model of the mentioned airplanes. The authors are using this as reference so the reader can relate what he/she is seeing in this paper to existing aircrafts. By doing such comparison, the author intends to demonstrate that the Parametric Model that has been created possesses the capability to simulate to some extend the shape of existing aircrafts. Finally from the results of this project it is concluded that the methodology in question is promising. Linking the two programs is possible and the aerodynamic characteristics of the models tested fall in the appropriate range. None the less the research must continue following the line that has been discussed in this report.
15

Designing Round-Trip Systems by Change Propagation and Model Partitioning

Seifert, Mirko 26 July 2011 (has links) (PDF)
Software development processes incorporate a variety of different artifacts (e.g., source code, models, and documentation). For multiple reasons the data that is contained in these artifacts does expose some degree of redundancy. Ensuring global consistency across artifacts during all stages in the development of software systems is required, because inconsistent artifacts can yield to failures. Ensuring consistency can be either achieved by reducing the amount of redundancy or by synchronizing the information that is shared across multiple artifacts. The discipline of software engineering that addresses these problems is called Round-Trip Engineering (RTE). In this thesis we present a conceptual framework for the design RTE systems. This framework delivers precise definitions for essential terms in the context of RTE and a process that can be used to address new RTE applications. The main idea of the framework is to partition models into parts that require synchronization - skeletons - and parts that do not - clothings. Once such a partitioning is obtained, the relations between the elements of the skeletons determine whether a deterministic RTE system can be built. If not, manual decisions may be required by developers. Based on this conceptual framework, two concrete approaches to RTE are presented. The first one - Backpropagation-based RTE - employs change translation, traceability and synchronization fitness functions to allow for synchronization of artifacts that are connected by non-injective transformations. The second approach - Role-based Tool Integration - provides means to avoid redundancy. To do so, a novel tool design method that relies on role modeling is presented. Tool integration is then performed by the creation of role bindings between role models. In addition to the two concrete approaches to RTE, which form the main contributions of the thesis, we investigate the creation of bridges between technical spaces. We consider these bridges as an essential prerequisite for performing logical synchronization between artifacts. Also, the feasibility of semantic web technologies is a subject of the thesis, because the specification of synchronization rules was identified as a blocking factor during our problem analysis. The thesis is complemented by an evaluation of all presented RTE approaches in different scenarios. Based on this evaluation, the strengths and weaknesses of the approaches are identified. Also, the practical feasibility of our approaches is confirmed w.r.t. the presented RTE applications.
16

Towards an industrial ALM (Application Lifecycle) Tool Integration

Markov, Georgi, Druzhinina, Olga January 2011 (has links)
Context. Application Lifecycle Management refers to the coordination of all aspects of software engineering, through a collection of integrated software development tools. More and more organizations are heavily relying on the ALM tools nowadays. Objectives. In this study we research ALM first as a business strategy, its roots, its advantages and disadvantages. As well as making a theoretical research, we seek out the setbacks of the practical side of ALM in order to find the areas needed for improvement, by investigating the ALM’s existing tools, interviewing ALM’s users, and using gained statistical data to derive practical facts about ALM. The goal of the thesis is to find out how ALM can be improved. Methods. The vast amount of sources, including articles, books, and journals is used to support our arguments and conclusions. A long online survey was carried with many participants to understand the practical side of ALM, as well as gain access to information about ALM’s setbacks. Results. The problems of ALM are recognized and named. Proposals are made in respect of how to deal with these problems. A list of what options need to be studied in the future, in order to improve the overall ALM design, and make it a powerful tool, is presented. A detailed plan for further research regarding this highly important issue is presented. Conclusions. We conclude that there are several ALM tool options on the market, all having their strengths and weaknesses. But in order for ALM to become an industrial solution and to be truly successful and effective in supporting the broader goals of the different organizations using it, the requests of the stakeholders towards deeper semantic integration between the various tool involved in the ALM processes need to be embodied in the current ALM offerings. We conclude that further research is needed in order to assess the proposals, and test the design ideas that are presented in the last chapter of this thesis. / This thesis concerns the authors and stakeholders of ALM. With the technological achievements taking place every day, and competition being very high, it is important to get the software product ready for release on time and of good quality. The current tools for managing of the application’s lifecycle are incoherent in terms of tool integration. In this thesis we describe the setbacks of ALM, according to interviewed stakeholders and authors of journals, articles and books. We conclude our thesis with the several proposed design options that may succeed in making ALM strong and consistent in the future. The proposed design mainly concerns the integration problems, and provides several potential solutions, aiming at easy to use and integrate tools. Further research areas are explained, and stated.
17

Designing Round-Trip Systems by Change Propagation and Model Partitioning

Seifert, Mirko 28 June 2011 (has links)
Software development processes incorporate a variety of different artifacts (e.g., source code, models, and documentation). For multiple reasons the data that is contained in these artifacts does expose some degree of redundancy. Ensuring global consistency across artifacts during all stages in the development of software systems is required, because inconsistent artifacts can yield to failures. Ensuring consistency can be either achieved by reducing the amount of redundancy or by synchronizing the information that is shared across multiple artifacts. The discipline of software engineering that addresses these problems is called Round-Trip Engineering (RTE). In this thesis we present a conceptual framework for the design RTE systems. This framework delivers precise definitions for essential terms in the context of RTE and a process that can be used to address new RTE applications. The main idea of the framework is to partition models into parts that require synchronization - skeletons - and parts that do not - clothings. Once such a partitioning is obtained, the relations between the elements of the skeletons determine whether a deterministic RTE system can be built. If not, manual decisions may be required by developers. Based on this conceptual framework, two concrete approaches to RTE are presented. The first one - Backpropagation-based RTE - employs change translation, traceability and synchronization fitness functions to allow for synchronization of artifacts that are connected by non-injective transformations. The second approach - Role-based Tool Integration - provides means to avoid redundancy. To do so, a novel tool design method that relies on role modeling is presented. Tool integration is then performed by the creation of role bindings between role models. In addition to the two concrete approaches to RTE, which form the main contributions of the thesis, we investigate the creation of bridges between technical spaces. We consider these bridges as an essential prerequisite for performing logical synchronization between artifacts. Also, the feasibility of semantic web technologies is a subject of the thesis, because the specification of synchronization rules was identified as a blocking factor during our problem analysis. The thesis is complemented by an evaluation of all presented RTE approaches in different scenarios. Based on this evaluation, the strengths and weaknesses of the approaches are identified. Also, the practical feasibility of our approaches is confirmed w.r.t. the presented RTE applications.
18

Tool Integration and Safety : A Foundation for Analysing the Impact of Tool Integrationon Non-functional Properties

Asplund, Fredrik January 2012 (has links)
The increasing complexity of embedded systems development is becoming difficult to handle with development environments based on disjoint engineering tools. Support for interactions between various engineering tools, especially through automated means, has therefore received an increased amount of attention during the last few years. The subsequent increase in the amount of tool integration is leading to an increased impact of tool integration on non-functional properties of development efforts, development environments and end products. At the same time there is a lack of methods and tools for analysing the relationship between these properties and tool integration. To establish a foundation for analysing this generic relationship, the specific relationship between tool integration and the safety of end products is analysed in this thesis. A survey was conducted to analyze the State of the Art of tool integration as related to safety. This survey specifically identified the lack of an efficient handling of tool integration by modern safety standards as an important concern. In relation to this survey, three theories were identified as of specific importance. These are the school of thought known as Systems Thinking, the Systems-Theoretic Accident Model and Processes (STAMP) causality model and the System-Theoretic Process Analysis (STPA) hazard analysis technique. Building on these theories, this thesis provides original contributions intended to (1) describe concepts and models related to tool integration and safety (the first and second contribution), (2) link tool integration to safety in a way that reduces complexity during analysis (the third contribution) and (3) propose how to interpret and make use of the implications of the presented theories and the first three contributions (the fourth and fifth contribution). • The first contribution is a new conceptual model of a development effort that emphasizes tool integration. • The second contribution is a new reference model for tool integration in highly heterogeneous environments. • The third contribution consists of nine safety-related tool chain properties, i.e. properties of tool chains that could mitigate at least part of the risks introduced by tool integration. • The fourth contribution is a proposition on how to identify safety implications due to a high level of automation of tool integration. • The fifth contribution is a proposition for a new software tool qualification process.
19

Adaptér OSLC pro analýzu softwaru / OSLC Adapter for Software Analysis

Vašíček, Ondřej January 2021 (has links)
Cílem této práce je poskytnout snadný způsob, jak rozšířit analyzační nástroj o rozhraní splňující standard OSLC. Takové rozhraní umožňuje jednoduchou integraci nástrojů s jinými nástroji nebo systémy, umožňuje jejich vzdálené použití skrze webové služby a umožňuje je jednoduše propojit s databází pro databázové dotazy a pro perzistentní uložení dat. Toto je dosaženo návrhem a implementací OSLC adaptéru pomocí sady nástrojů Eclipse Lyo. Adaptér používá jako rozhraní doménu OSLC Automation a je dostatečně univerzální na to, aby skrze toto rozhraní pokryl funkcionalitu většiny analyzačních nástrojů za pomocí jejich stávajících rozhraní na příkazové řádce. Tato práce poskytuje úvod k OSLC, Eclipse Lyo a souvisejícím konceptům. Dále tato práce definuje požadavky a odlišnosti různých analyzačních nástrojů a diskutuje návrh adaptéru a faktory, které ovlivnily návrhová rozhodnutí. A nakonec prezentuje implementovaný adaptér a jeho vyhodnocení pomocí automatizované testovací sady a pomocí experimentů s řadou analyzačních nástrojů. Nejvýznamnější ukazatel hodnocení vytvořeného adaptéru je to, že už teď je používán v praxi pro přidání OSLC rozhraní k nástrojům ANaConDA, Perun, Spectra (všechny tři vyvíjené na VeriFIT) a HiLiTE (Honeywell).

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