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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

Automatic test vector generation and coverage analysis in model-based software development

Andersson, Jonny January 2005 (has links)
Thorough testing of software is necessary to assure the quality of a product before it is released. The testing process requires substantial resources in software development. Model-based software development provides new possibilities to automate parts of the testing process. By automating tests, valuable time can be saved. This thesis focuses on different ways to utilize models for automatic generation of test vectors and how test coverage analysis can be used to assure the quality of a test suite or to find "dead code" in a model. Different test-automation techniques have been investigated and applied to a model of an adaptive cruise control system (ACC) used at Scania. Source code has been generated automatically from the model, model coverage and code coverage has therefore been compared. The work with this thesis resulted in a new method to create test vectors for models based on a combinatorial test technique.
12

Design Philosophy for User Friendly Parameter Handler

Angarita Soto, Angie January 2012 (has links)
DCU2 (Drive Control Unit 2) is an important control system used in applications for train systems that are configured by a set of parameters. Traditionally, parameterization is conducted by using an excel workbook during the software development. The parameters are set up and further export the parameters to the compilation step. Such approach has a number of disadvantages, e.g., delays on the validation and verification steps, system configuration overhead, and suboptimal system reliability generated by the parameter configurations. To improve the parameterization process, this thesis implements a model-based software architecture approach and automotive industry standards via rapid prototyping by using scrum methodology. We do this by using Matlab/Simulink, TDL (Time Description Language) and UML (Unified Modeling Language) architectural description languages to enable different views of the software architecture. We then develop different prototypes that implement ASAM (Association for Standardization of Automation and Measuring Systems) standards like XCP protocol over Ethernet (code ASAM MCD-1 XCP V1.1.0) and ASAP2 (code ASAM MCD-2 MC) in every scrum sprint. An evaluation then shows that the thesis successfully implements previously defined standards that use commercial tools from e.g., Vector, proving that the parameter‟s unit control can be handled via online calibration and measurement, leading to a significant improvement in Bombardier‟s software development process in a distributed development environment.
13

Promoting Traits into Model-Driven Development

Abdelzad, Vahdat January 2017 (has links)
Traits are primitive units of code reuse that serve as building blocks of classes. In this research, we enhance reuse by extending the capabilities of traits; in particular, we add modeling abstractions to them. Traits have a variety of benefits, including facilitating reuse and separation of concerns. They have appeared in several programming languages, particularly derivatives of Smalltalk. However, there is still no support for traits that contain modeling abstractions, and no straightforward support for them in general-purpose programming languages. The latter is due to structural concerns that exist for them at runtime, especially traits that contain modeling abstractions. Model-driven technologies are making inroads into the development community, albeit slowly. Modeling abstractions such as state machines and associations provide new opportunities for reuse, and can be combined with inheritance for even greater reusability. However, issues with inheritance apply also when these new abstractions are inheritable units. This suggests that traits and models ought to be able to be synergistically combined. We perform a comprehensive analysis of using modeling elements in traits. We implement such traits in Umple, which is a model-oriented programming language that permits embedding of programming concepts into models. The contributions of the thesis are: a) Adding new elements including state machines and associations into traits, hence bringing more reusability, modularity, and applications to traits; b) Developing an algorithm that allows reusing, extending, and composing state machines through traits; c) Extending traits with required interfaces so dependencies at the semantic level become part of their usage, rather than simple syntactic capture; d) Adding template parameters with associations in traits, offering new applications for traits in which it is possible to define design patterns and to have a library of most-used functionality; e) The implementation of all the above concepts, including generating code in multiple general-purpose programming languages through automatic model transformation.
14

Towards a Holistic Development Approach for Adaptable Manufacturing Paradigms : A Case Study of Evolvable Production Systems

Rahatulain, Afifa January 2016 (has links)
Increasing global competition, market uncertainties and high product variance are a few of the factors posing challenges to the existing manufacturing industry. Having a quick response to market fluctuations and adapting to changing customer demands while maintaining shorter lead times and low costs are a few of the major challenges. The main focus of this thesis is on Evolvable Production Systems, which is one of the promising solutions to deal with the emerging manufacturing challenges by changing the conventional manufacturing systems towards a more flexible, intelligent and adaptable approach. Although promising, further research is needed in several directions for a wider industrial acceptance of EPS. The directions include but are not limited to methodological aspects, tool support, etc. throughout the development lifecycle. This thesis aims to provide a basis for a holistic model-based development methodology for evolvable production systems. One of the main contributionsof this work is the identification of major architectural elements (i.e stakeholders,concerns, viewpoints and views) and their dependencies on each other.This work shall serve as a basis for establishing a well-defined architectural framework for EPS. The second important contribution of this thesis is the development of a domain specific modeling language (EPS- DSL) based on the existing EPS ontology. The DSM platform does not only store the domain knowledge in the form of models but also provides support for the re-use of these models, i.e. enables utilization of the domain ontology during system development. Moreover, the automatic code generation support for the module library presented in this work, significantly reduces the risks of information discrepancies when transferring data from one abstraction level to another. The existing EPS ontology is also evaluated from a holistic perspective and resulted in contributing a few improvement suggestions for achieving a seamless model-based development approach. Evaluation of Simulink/SimEvents as a modeling and simulation tool for EPS is the third main contribution of this thesis. One of the main advantages of evaluating this tool for EPS is the opportunity to analyze the complete system behavior on a single modeling platform. The integration of agent-based system behavior (discrete event) with dynamic system behavior (continuous &amp; discrete time) provides a holistic modeling approach and implies less information inconsistencies. / <p>QC 20160429</p>
15

Model and tool integration in high level design of embedded systems

Shi, Jianlin January 2007 (has links)
The development of advanced embedded systems requires a systematic approach as well as advanced tool support in dealing with their increasing complexity. This complexity is due to the increasing functionality that is implemented in embedded systems and stringent (and conflicting) requirements placed upon such systems from various stakeholders. The corresponding system development involves several specialists employing different modeling languages and tools. Integrating their work and the results thereof then becomes a challenge. In order to facilitate system architecting and design integration of different models, an approach that provides dedicated workspaces/views supported by structured information management and information exchange between domain models and tools is required. This work is delimited to the context of embedded systems design and taking a model based approach. The goal of the work is to study possible technical solutions for integrating different models and tools, and to develop knowledge, support methods and a prototype tool platform. To this end, this thesis examines a number of approaches that focus on the integration of multiple models and tools. Selected approaches are compared and characterized, and the basic mechanisms for integration are identified. Several scenarios are identified and further investigated in case studies. Two case studies have been performed with model transformations as focus. In the first one, integration of Matlab/Simulink® and UML2 are discussed with respect to the motivations, technical possibilities, and challenges. A preliminary mapping strategy, connecting a subset of concepts and constructs of Matlab/Simulink® and UML2, is presented together with a prototype implementation in the Eclipse environment. The second case study aims to enable safety analysis based on system design models in a UML description. A safety analysis tool, HiP-HOPS (Hierarchically Performed Hazard Origin and Propagation Studies), is partially integrated with a UML tool where an EAST-ADL2 based architecture model is developed. The experience and lessons learned from the experiments are reported in this thesis. Multiple specific views are involved in the development of embedded systems. This thesis has studied the integration between system architecture design, function development and safety analysis through using UML tools, Matlab/Simulink, and HiP-HOPS. The results indicate that model transformations provide a feasible and promising solution for integrating multiple models and tools. The contributions are believed to be valid for a large class of advanced embedded systems. However, the developed transformations so far are not really scalable. A systematic approach for efficient development of model transformations is desired to standardize the design process and reuse developed transformations. To this end, future studies will be carried out to develop guidelines for model and tool integration and to provide support for structured information at both meta level and instance level. / QC 20101116
16

Modellbasierte Entwicklungsmethoden als Enabler von Smart Services im Kontext von Industrie 4.0

Kampfmann, Rüdiger, Menager, Nils 29 May 2018 (has links) (PDF)
Ständig steigende Anforderungen an industrielle Anlagen, wie zum Beispiel ein höherer Durchsatz oder mehr Flexibilität, führen zu einer gesteigerten Komplexität dieser Systeme. Zusätzlich verlagert sich immer mehr Funktionalität aus dem Hardware- in den Softwarebereich, so dass dessen Bedeutung stetig zunimmt. Diesem Wandel mit wettbewerbsfähiger Entwicklungszeit zu begegnen, ist eine der wichtigsten Herausforderungen im Automatisierungssektor. Einen Ansatz hierzu stellt die Verwendung modellbasierter Entwicklungsmethoden dar. Während in den frühen Phasen des Entwicklungsprozesses modellbasierte Methoden zunehmend häufiger eingesetzt werden, besteht vor allem in den späteren Entwicklungsphasen sowie in der Phase des Betriebs erheblicher Nachholbedarf. In diesem Beitrag werden zunächst die bereits heute in der Praxis verwendeten Methoden am Beispiel einer komplexen Roboterkinematik vorgestellt. Anschließend wird im Wesentlichen die Phase des Betriebs betrachtet und dargestellt, welche Mehrwerte sich durch die Verwendung so genannter Smart Services auf Basis der bereits vorhandenen physikalischen Simulationsmodelle ergeben.
17

Model-Based Development of Multi-iRobot Simulation and Control

January 2012 (has links)
abstract: This thesis introduces the Model-Based Development of Multi-iRobot Toolbox (MBDMIRT), a Simulink-based toolbox designed to provide the means to acquire and practice the Model-Based Development (MBD) skills necessary to design real-time embedded system. The toolbox was developed in the Cyber-Physical System Laboratory at Arizona State University. The MBDMIRT toolbox runs under MATLAB/Simulink to simulate the movements of multiple iRobots and to control, after verification by simulation, multiple physical iRobots accordingly. It adopts the Simulink/Stateflow, which exemplifies an approach to MBD, to program the behaviors of the iRobots. The MBDMIRT toolbox reuses and augments the open-source MATLAB-Based Simulator for the iRobot Create from Cornell University to run the simulation. Regarding the mechanism of iRobot control, the MBDMIRT toolbox applies the MATLAB Toolbox for the iRobot Create (MTIC) from United States Naval Academy to command the physical iRobots. The MBDMIRT toolbox supports a timer in both the simulation and the control, which is based on the local clock of the PC running the toolbox. In addition to the build-in sensors of an iRobot, the toolbox can simulate four user-added sensors, which are overhead localization system (OLS), sonar sensors, a camera, and Light Detection And Ranging (LIDAR). While controlling a physical iRobot, the toolbox supports the StarGazer OLS manufactured by HAGISONIC, Inc. / Dissertation/Thesis / Model-Based Development of Multi-iRobot Toolbox (version 1.0) / M.S. Computer Science 2012
18

Automated Modeling of Human-in-the-Loop Systems

Noah M Marquand (11587612) 22 November 2021 (has links)
Safety in human in the loop systems, systems that change behavior with human input, is difficult to achieve. This difficulty can cost lives. As desired system capability grows, so too does the requisite complexity of the system. This complexity can result in designers not accounting for every use case of the system and unintentionally designing in unsafe behavior. Furthermore, complexity of operation and control can result in operators becoming confused during use or receiving insufficient training in the first place. All these cases can result in unsafe operations. One method of improving safety is implementing the use of formal models during the design process. These formal models can be analyzed mathematically to detect dangerous conditions, but can be difficult to produce without time, money, and expertise.<br> This document details the study of potential methods for constructing formal models autonomously from recorded observations of system use, minimizing the need for system expertise, saving time, money, and personnel in this safety critical process. I first discuss how different system characteristics affect system modeling, isolating specific traits that most clearly affect the modeling process Then, I develop a technique for modeling a simple, digital, menu-based system based on a record of user inputs. This technique attempts to measure the availability of different inputs for the user, and then distinguishes states by comparing input availabilities. From there, I compare paths between states and check for shared behaviors. I then expand the general procedure to capture the behavior of a flight simulator. This system more closely resembles real-world safety critical systems and can therefore be used to approximate a real use case of the method outlined. I use machine learning tools for statistical analysis, comparing patterns in system behavior and user behaviors. Last, I discuss general conclusions on how the modeling approaches outlined in this document can be improved and expanded upon.<br> For simple systems, we find that inputs alone can produce state machines, but without corresponding system information, they are less helpful for determining relative safety of different use cases than is needed. Through machine learning, we find that records of complex system use can be decomposed into sets of nominal and anomalous states but determining the causal link between user inputs and transitions between these conditions is not simple and requires further research.
19

Modellbasierte Entwicklungsmethoden als Enabler von Smart Services im Kontext von Industrie 4.0

Kampfmann, Rüdiger, Menager, Nils 29 May 2018 (has links)
Ständig steigende Anforderungen an industrielle Anlagen, wie zum Beispiel ein höherer Durchsatz oder mehr Flexibilität, führen zu einer gesteigerten Komplexität dieser Systeme. Zusätzlich verlagert sich immer mehr Funktionalität aus dem Hardware- in den Softwarebereich, so dass dessen Bedeutung stetig zunimmt. Diesem Wandel mit wettbewerbsfähiger Entwicklungszeit zu begegnen, ist eine der wichtigsten Herausforderungen im Automatisierungssektor. Einen Ansatz hierzu stellt die Verwendung modellbasierter Entwicklungsmethoden dar. Während in den frühen Phasen des Entwicklungsprozesses modellbasierte Methoden zunehmend häufiger eingesetzt werden, besteht vor allem in den späteren Entwicklungsphasen sowie in der Phase des Betriebs erheblicher Nachholbedarf. In diesem Beitrag werden zunächst die bereits heute in der Praxis verwendeten Methoden am Beispiel einer komplexen Roboterkinematik vorgestellt. Anschließend wird im Wesentlichen die Phase des Betriebs betrachtet und dargestellt, welche Mehrwerte sich durch die Verwendung so genannter Smart Services auf Basis der bereits vorhandenen physikalischen Simulationsmodelle ergeben.
20

Modellbasierte Entwicklung von Energiemanagement-Methoden für Flugzeug-Energiesysteme

Schlabe, Daniel 26 January 2017 (has links) (PDF)
Ein geringer Treibstoffverbrauch ist aufgrund von ökologischen und ökonomischen Zielen für die zivile Luftfahrt von großer Bedeutung. Daher werden seit Jahrzehnten konventionell hydraulisch oder pneumatisch betriebene Flugzeugsysteme durch elektrisch betriebene Systeme ersetzt. Dieser Trend wird auch als „More Electric Aircraft (MEA)“ bezeichnet. In bisherigen Studien waren MEA-Architekturen zwar effizienter, jedoch deutlich schwerer als die konventionellen Architekturen. Basierend auf ökonomischen Modellen wird in der vorliegenden Arbeit die modellbasierte Entwicklung eines intelligenten Energiemanagements für Flugzeug-Energiesysteme demonstriert. Das Energiemanagement ermöglicht eine deutliche Reduktion der Systemmasse, verbessert die Energieeffizienz und kann damit den Treibstoffverbrauch eines MEA beträchtlich reduzieren. Insbesondere durch die integrierte und frühzeitige Entwicklung des Energiemanagements mit dem elektrischen System in der Modellbeschreibungssprache Modelica lassen sich die Systemkomponenten mit realistischen Lastprofilen dimensionieren und dadurch die Systemmasse reduzieren. Anhand eines elektrischen Referenzsystems wird das Optimierungspotenzial des Energiemanagements bezüglich Massenreduktion und Energieeffizienzsteigerung quantifiziert und am Systemmodell validiert. Es ergibt sich für das Systemmodell eine Reduktion der Systemmasse um 32 % sowie eine leichte Verbesserung der Energieeffizienz. Durch die multiphysikalische Implementierung des Energiemanagements lässt sich dieses auch für das thermische Management im Flugzeug verwenden. Hierbei kann eine deutliche Verbesserung der Energieeffizienz für die Bereitstellung von Kühlleistung erzielt werden. Aufgrund der erreichten Vorteile sollte ein Energiemanagement bei der Entwicklung zukünftiger Flugzeugenergiesysteme in Betracht gezogen werden. Insbesondere beim MEA existiert ein großes Optimierungspotenzial durch das Energiemanagement. Die Ausführungen in der vorliegenden Arbeit sollen als Motivation für die Flugzeugindustrie dienen, mit realistischen Lastprofilen zu dimensionieren und die modellbasierte und integrierte Entwicklung eines Energiemanagements mit den Energiesystemen bereits in frühen Entwicklungsphasen durchzuführen. / Low fuel consumption is a major concern in civil aerospace due to environmental and economic objectives. Hence, conventional hydraulically or pneumatically driven aircraft systems have been replaced by electrically driven systems for decades. This trend is also known as More Electric Aircraft (MEA). In former studies, MEA architectures were more efficient, but much heavier than their conventional counterparts. The present work demonstrates the model-based development of intelligent energy management algorithms for aircraft energy systems based on economic models. This energy management facilitates a significant reduction of system mass, improves energy efficiency and can hence reduce fuel consumption of MEA considerably. In particular, the integrated development of an energy management along with the electrical system in the Modelica modelling language enables sizing of system components with realistic load profiles. Hence, this reduces the system mass. The optimization potential of the energy management is quantified and validated by means of an electrical reference system model. Applying the energy management, the mass of this system model can be reduced by 32 % and the energy efficiency can be improved slightly. Due to the multi-physical modelling of the energy management, it can also be applied to thermal management of aircraft systems. Thus, the energy efficiency of the cooling system can be improved significantly. As a result of the demonstrated benefits, an energy management should be considered for future development of aircraft energy systems. Especially for MEA, there is tremendous optimization potential for the energy management. Hence, the present work shall motivate aircraft industry to size aircraft systems with realistic load profiles and perform a model-based and integrated development of the energy management along with the electrical system in early phases of the system design process.

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