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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.
101

Instrumentation and Coverage Analysis of Cyber Physical System Models

January 2016 (has links)
abstract: A Cyber Physical System consists of a computer monitoring and controlling physical processes usually in a feedback loop. These systems are increasingly becoming part of our daily life ranging from smart buildings to medical devices to automobiles. The controller comprises discrete software which may be operating in one of the many possible operating modes and interacting with a changing physical environment in a feedback loop. The systems with such a mix of discrete and continuous dynamics are usually termed as hybrid systems. In general, these systems are safety critical, hence their correct operation must be verified. Model Based Design (MBD) languages like Simulink are being used extensively for the design and analysis of hybrid systems due to the ease in system design and automatic code generation. It also allows testing and verification of these systems before deployment. One of the main challenges in the verification of these systems is to test all the operating modes of the control software and reduce the amount of user intervention. This research aims to provide an automated framework for the structural analysis and instrumentation of hybrid system models developed in Simulink. The behavior of the components introducing discontinuities in the model are automatically extracted in the form of state transition graphs. The framework is integrated in the S-TaLiRo toolbox to demonstrate the improvement in mode coverage. / Dissertation/Thesis / Masters Thesis Computer Science 2016
102

From Formal Requirement Analysis to Testing and Monitoring of Cyber-Physical Systems

January 2017 (has links)
abstract: Cyber-Physical Systems (CPS) are being used in many safety-critical applications. Due to the important role in virtually every aspect of human life, it is crucial to make sure that a CPS works properly before its deployment. However, formal verification of CPS is a computationally hard problem. Therefore, lightweight verification methods such as testing and monitoring of the CPS are considered in the industry. The formal representation of the CPS requirements is a challenging task. In addition, checking the system outputs with respect to requirements is a computationally complex problem. In this dissertation, these problems for the verification of CPS are addressed. The first method provides a formal requirement analysis framework which can find logical issues in the requirements and help engineers to correct the requirements. Also, a method is provided to detect tests which vacuously satisfy the requirement because of the requirement structure. This method is used to improve the test generation framework for CPS. Finally, two runtime verification algorithms are developed for off-line/on-line monitoring with respect to real-time requirements. These monitoring algorithms are computationally efficient, and they can be used in practical applications for monitoring CPS with low runtime overhead. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2017
103

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
104

Stochastic Optimization and Real-Time Scheduling in Cyber-Physical Systems

January 2012 (has links)
abstract: A principal goal of this dissertation is to study stochastic optimization and real-time scheduling in cyber-physical systems (CPSs) ranging from real-time wireless systems to energy systems to distributed control systems. Under this common theme, this dissertation can be broadly organized into three parts based on the system environments. The first part investigates stochastic optimization in real-time wireless systems, with the focus on the deadline-aware scheduling for real-time traffic. The optimal solution to such scheduling problems requires to explicitly taking into account the coupling in the deadline-aware transmissions and stochastic characteristics of the traffic, which involves a dynamic program that is traditionally known to be intractable or computationally expensive to implement. First, real-time scheduling with adaptive network coding over memoryless channels is studied, and a polynomial-time complexity algorithm is developed to characterize the optimal real-time scheduling. Then, real-time scheduling over Markovian channels is investigated, where channel conditions are time-varying and online channel learning is necessary, and the optimal scheduling policies in different traffic regimes are studied. The second part focuses on the stochastic optimization and real-time scheduling involved in energy systems. First, risk-aware scheduling and dispatch for plug-in electric vehicles (EVs) are studied, aiming to jointly optimize the EV charging cost and the risk of the load mismatch between the forecasted and the actual EV loads, due to the random driving activities of EVs. Then, the integration of wind generation at high penetration levels into bulk power grids is considered. Joint optimization of economic dispatch and interruptible load management is investigated using short-term wind farm generation forecast. The third part studies stochastic optimization in distributed control systems under different network environments. First, distributed spectrum access in cognitive radio networks is investigated by using pricing approach, where primary users (PUs) sell the temporarily unused spectrum and secondary users compete via random access for such spectrum opportunities. The optimal pricing strategy for PUs and the corresponding distributed implementation of spectrum access control are developed to maximize the PU's revenue. Then, a systematic study of the nonconvex utility-based power control problem is presented under the physical interference model in ad-hoc networks. Distributed power control schemes are devised to maximize the system utility, by leveraging the extended duality theory and simulated annealing. / Dissertation/Thesis / Ph.D. Electrical Engineering 2012
105

Software Architecture for a Cyber-Physical Ecosystem in support of Open Innovation - : Balancing Open Innovation and Governance through Software Architecture

Platanias, Efthymios January 2017 (has links)
This is a qualitative exploratory study of Software Architecture in Cyber-Physical Ecosystems. Software Architecture plays a pivotal role to Software Ecosystems and, apart from Functional and non-Functional requirements, it is affected by factors of a different nature. The purpose of this paper is to identify these factors and describe their relationship with the ecosystem’s architecture. Several owners of Cyber-Physical systems are in the process of setting up new ecosystems by sharing functionalities of their proprietary platform with third-party developers. This makes Architecture that supports Open Innovation critical to this endeavor. We believe that the application of Software Ecosystem best practices  to the domain of Cyber-Physical Systems is an interesting subject. An exploratory literature study was conducted to create a conceptual model which describes the relationship of architecture with the factors presented above. This study resulted in a conceptual model which supports the decision making process of the platform owner during the various stages of the ecosystem’s lifecycle.
106

A Hierarchical Architectural Framework for Securing Unmanned Aerial Systems

Leccadito, Matthew 01 January 2017 (has links)
Unmanned Aerial Systems (UAS) are becoming more widely used in the new era of evolving technology; increasing performance while decreasing size, weight, and cost. A UAS equipped with a Flight Control System (FCS) that can be used to fly semi- or fully-autonomous is a prime example of a Cyber Physical and Safety Critical system. Current Cyber-Physical defenses against malicious attacks are structured around security standards for best practices involving the development of protocols and the digital software implementation. Thus far, few attempts have been made to embed security into the architecture of the system considering security as a holistic problem. Therefore, a Hierarchical, Embedded, Cyber Attack Detection (HECAD) framework is developed to provide security in a holistic manor, providing resiliency against cyber-attacks as well as introducing strategies for mitigating and dealing with component failures. Traversing the hardware/software barrier, HECAD provides detection of malicious faults at the hardware and software level; verified through the development of an FPGA implementation and tested using a UAS FCS.
107

Cyber-Physical Production Systems - Herausforderungen bei Modellierung und Informationsmanagement [Präsentationsfolien]: EEE Dresden 30.06.2016

Gerhard, Detlef January 2016 (has links)
No description available.
108

Innovationsforum open4INNOVATION2012 regional kooperativ-global innovativ: Beiträge zum Fachforum

Gräning, André, Röttger, Simone 27 June 2012 (has links)
Die Zukunft liegt bereits heute schon im Internet der Dinge, Daten, Dienste und Personen. Informations- und Kommunikationstechnologien (IKT) beeinflussen vermehrt die alltäglichen Abläufe, übernehmen im Ernstfall lebenserhaltende Körperfunktionen, unterstützen Arbeits- und Produktionsprozesse und halten Einzug in unsere Wohnbereiche. Dabei rückt der Gedanke einer anwendungsnahen und integrierten Sicht von Software zunehmend in den Vordergrund und verlangt deshalb interdisziplinäre Ansätze. Eine frühzeitige technische Abstimmung zwischen Soft- und Hardware sowie unterschiedlichen technischen Öko-Systemen wird dabei notwendiger und fordert Politik, Wissenschaft und Wirtschaft in gleichem Maße. Das Innovationsforum open4INNOVATION2012 am 9.Mai bot dazu Praktikern und Akademikern eine Plattform für den interdisziplinären und fachbereichsübergreifenden Austausch zu neuen und anwendungsnahen IKT-Ansätzen. Unter dem Motto regional kooperativ, global innovativ galt es dabei regional politische, wirtschaftliche und wissenschaftliche Kompetenzen zu bündeln, um globale Märkte erfolgreich zu bestreiten. In dem vorliegenden Tagungsband finden Sie die Beiträge des Fachforums, welches ein Hauptformat der Veranstaltung darstellte. Zusätzlich kam es auf dem Innovationsforum open4INNOVATION2012 erstmals zur aktiven Vernetzung sächsischer Forschergruppen, deren wissenschaftlicher Schwerpunkt die Robotik ist. Auf diesem ersten sächsischen Robotertreffen stand vor allem die Arbeit mit humanoiden Robotern im Mittelpunkt.
109

Self-managed Workflows for Cyber-physical Systems

Seiger, Ronny 03 December 2018 (has links)
Workflows are a well-established concept for describing business logics and processes in web-based applications and enterprise application integration scenarios on an abstract implementation-agnostic level. Applying Business Process Management (BPM) technologies to increase autonomy and automate sequences of activities in Cyber-physical Systems (CPS) promises various advantages including a higher flexibility and simplified programming, a more efficient resource usage, and an easier integration and orchestration of CPS devices. However, traditional BPM notations and engines have not been designed to be used in the context of CPS, which raises new research questions occurring with the close coupling of the virtual and physical worlds. Among these challenges are the interaction with complex compounds of heterogeneous sensors, actuators, things and humans; the detection and handling of errors in the physical world; and the synchronization of the cyber-physical process execution models. Novel factors related to the interaction with the physical world including real world obstacles, inconsistencies and inaccuracies may jeopardize the successful execution of workflows in CPS and may lead to unanticipated situations. This thesis investigates properties and requirements of CPS relevant for the introduction of BPM technologies into cyber-physical domains. We discuss existing BPM systems and related work regarding the integration of sensors and actuators into workflows, the development of a Workflow Management System (WfMS) for CPS, and the synchronization of the virtual and physical process execution as part of self-* capabilities for WfMSes. Based on the identified research gap, we present concepts and prototypes regarding the development of a CPS WFMS w.r.t. all phases of the BPM lifecycle. First, we introduce a CPS workflow notation that supports the modelling of the interaction of complex sensors, actuators, humans, dynamic services and WfMSes on the business process level. In addition, the effects of the workflow execution can be specified in the form of goals defining success and error criteria for the execution of individual process steps. Along with that, we introduce the notion of Cyber-physical Consistency. Following, we present a system architecture for a corresponding WfMS (PROtEUS) to execute the modelled processes-also in distributed execution settings and with a focus on interactive process management. Subsequently, the integration of a cyber-physical feedback loop to increase resilience of the process execution at runtime is discussed. Within this MAPE-K loop, sensor and context data are related to the effects of the process execution, deviations from expected behaviour are detected, and compensations are planned and executed. The execution of this feedback loop can be scaled depending on the required level of precision and consistency. Our implementation of the MAPE-K loop proves to be a general framework for adding self-* capabilities to WfMSes. The evaluation of our concepts within a smart home case study shows expected behaviour, reasonable execution times, reduced error rates and high coverage of the identified requirements, which makes our CPS~WfMS a suitable system for introducing workflows on top of systems, devices, things and applications of CPS.:1. Introduction 15 1.1. Motivation 15 1.2. Research Issues 17 1.3. Scope & Contributions 19 1.4. Structure of the Thesis 20 2. Workflows and Cyber-physical Systems 21 2.1. Introduction 21 2.2. Two Motivating Examples 21 2.3. Business Process Management and Workflow Technologies 23 2.4. Cyber-physical Systems 31 2.5. Workflows in CPS 38 2.6. Requirements 42 3. Related Work 45 3.1. Introduction 45 3.2. Existing BPM Systems in Industry and Academia 45 3.3. Modelling of CPS Workflows 49 3.4. CPS Workflow Systems 53 3.5. Cyber-physical Synchronization 58 3.6. Self-* for BPM Systems 63 3.7. Retrofitting Frameworks for WfMSes 69 3.8. Conclusion & Deficits 71 4. Modelling of Cyber-physical Workflows with Consistency Style Sheets 75 4.1. Introduction 75 4.2. Workflow Metamodel 76 4.3. Knowledge Base 87 4.4. Dynamic Services 92 4.5. CPS-related Workflow Effects 94 4.6. Cyber-physical Consistency 100 4.7. Consistency Style Sheets 105 4.8. Tools for Modelling of CPS Workflows 106 4.9. Compatibility with Existing Business Process Notations 111 5. Architecture of a WfMS for Distributed CPS Workflows 115 5.1. Introduction 115 5.2. PROtEUS Process Execution System 116 5.3. Internet of Things Middleware 124 5.4. Dynamic Service Selection via Semantic Access Layer 125 5.5. Process Distribution 126 5.6. Ubiquitous Human Interaction 130 5.7. Towards a CPS WfMS Reference Architecture for Other Domains 137 6. Scalable Execution of Self-managed CPS Workflows 141 6.1. Introduction 141 6.2. MAPE-K Control Loops for Autonomous Workflows 141 6.3. Feedback Loop for Cyber-physical Consistency 148 6.4. Feedback Loop for Distributed Workflows 152 6.5. Consistency Levels, Scalability and Scalable Consistency 157 6.6. Self-managed Workflows 158 6.7. Adaptations and Meta-adaptations 159 6.8. Multiple Feedback Loops and Process Instances 160 6.9. Transactions and ACID for CPS Workflows 161 6.10. Runtime View on Cyber-physical Synchronization for Workflows 162 6.11. Applicability of Workflow Feedback Loops to other CPS Domains 164 6.12. A Retrofitting Framework for Self-managed CPS WfMSes 165 7. Evaluation 171 7.1. Introduction 171 7.2. Hardware and Software 171 7.3. PROtEUS Base System 174 7.4. PROtEUS with Feedback Service 182 7.5. Feedback Service with Legacy WfMSes 213 7.6. Qualitative Discussion of Requirements and Additional CPS Aspects 217 7.7. Comparison with Related Work 232 7.8. Conclusion 234 8. Summary and Future Work 237 8.1. Summary and Conclusion 237 8.2. Advances of this Thesis 240 8.3. Contributions to the Research Area 242 8.4. Relevance 243 8.5. Open Questions 245 8.6. Future Work 247 Bibliography 249 Acronyms 277 List of Figures 281 List of Tables 285 List of Listings 287 Appendices 289
110

A Resource and Criticality Aware Cyber-Physical System with Robots for Precision Animal Agriculture

Upinder Kaur (16642614) 26 July 2023 (has links)
<p>Precision livestock farming (PLF) has emerged as a solution to address global challenges related to food scarcity, increasing demand for animal products, slim profit margins in livestock production, and growing societal concerns regarding farm animal welfare. By offering individualized care for animals, PLF aims to provide labor savings, enhanced monitoring, and improved control capabilities within complex farming systems, enabled by digital technologies. The adoption of an individual-centric approach to farming through PLF is anticipated to enhance farm productivity and ensure ethical treatment of animals while mitigating concerns associated with labor shortages in modern intensive farming operations. Real-time continuous monitoring of each animal enables precise and accurate health and well-being management. However, to achieve these benefits, large-scale animal farms require commercially viable technological solutions for individualized care and welfare. Cyber-physical systems (CPSs) offer precise monitoring and control and present a promising avenue for PLF but pose significant implementation challenges.</p> <p>  In this work, a generalizable CPS architecture was formalized with active robotic nodes that can realize adaptive continuous real-time animal health monitoring to maximize productivity, animal welfare, and sustainability. Taking the example of dairy farming, a resource- and criticality-aware CPS was developed that enables real-time resource-aware sensing, adaptive control, and agile networking with an emphasis on handling emergencies autonomously. Using a decentralized approach, each node was made capable of optimizing its operation to be resource conscious, while also being able to identify emergency conditions in real-time. In this novel design, we accommodate the social dynamics of the herd and effectively address the various types of emergencies possible in PLF. Moreover, the communication was customized for the unique needs of animal agriculture, wherein it reduced latency and power consumption while ensuring collision-free two-way synchronization with adaptive range extension for emergency conditions. Further, since the CPS was centered around animals, a special robust security layer was also developed and implemented to protect the active embodied nodes against known and unknown malicious attacks. The proposed CPS reference architecture provides a foundation for implementing individualized care and welfare, ultimately improving the efficiency and sustainability of livestock operations.</p>

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