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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.
41

Thruster fault diagnosis and accommodation for overactuated open-frame underwater vehicles

Omerdic, Edin January 2004 (has links)
The work presented in the thesis concerns the design and development of a novel thruster fault diagnosis and accommodation system (PDAS) for overactuated, open-frame underwater vehicles. The remotely operated vehicles (ROVs) considered in this thesis have four thrusters for motion in the horizontal plane with three controllable degrees of freedom (DoF). Due to the redundancy resulting from this configuration, for the case of a partial fault or a total fault in a single thruster it is possible to reallocate control among operable thrusters in order that the ROV pilot is able to maintain control of the faulty ROV and to continue with missions. The proposed PDAS consists of two subsystems: a fault diagnosis subsystem (FDS) and a fault accommodation subsystem (FAS). The FDS uses fault detector units to monitor thruster states. Robust and reliable interrogation of thruster states, and subsequent identification of faults, is accomplished using methods based on the integration of selforganising maps and fuzzy logic clustering. The FAS uses information provided by the FDS to perform an appropriate redistribution of thruster demands in order to accommodate faults. The FAS uses a hybrid approach for control allocation, which integrates the pseudoinverse method and the fixed-point iterations method. A control energy cost function is used as the optimisation criteria. In fault-free and faulty cases the FAS finds the optimal solution, which minimises this criteria. The concept of feasible region is developed in order to visualise thruster velocity saturation bounds. The PDAS provides a dynamic update of saturation bounds using a complex three-dimensional visualisation of the feasible region (attainable command set), such that the ROV pilot is informed with the effects of thruster fault accommodation, incorporated in the new shape of the attainable command set. In this way the ROV pilot can easy adapt to newly created changes and continue the mission in the presence of a fault. The prototype of the PDAS was developed in the MATLAB environment as a Simulink model, which includes a nonlinear model of an ROV with 6 DOF, propulsion system and a hand control unit. The hand control unit was simulated in hardware using a joystick as input device to generate command signals. Different fault conditions are simulated in order to investigate the performance of the PDAS. A virtual underwater world was developed, which enabled tuning, testing and evaluation of the PDAS using simulations of two underwater vehicles (FALCON, Seaeye Marine Ltd. and URIS, University of Girona) in a 'realistic' underwater environment. The performance of the PDAS was demonstrated and evaluated via tank trials of the FALCON ROV in QinetiQ Ocean Basin Tank at Haslar, where the existing control software was enhanced with the PDAS algorithm. The results of real-world experiments confirmed the effectiveness of the PDAS in maintaining vehicle manoeuvrability and in preserving the vehicle mission in the presence of thruster faults.
42

Návrh propojení a programových modulů pro řízení robotické buňky pro zakládání dílů / Design of interconnections and program modules for robotic cell control for parts creation

Fursov, Ihor January 2019 (has links)
This diploma thesis describes design of interconnections and program modules for robotic cell control for parts creation. Research of this work is focused on industrial comunication protocols. The next part analyzes separate parts of the cell and their ways of connection. Futhermore, control structures of the cell are proposed and after comparison of them SCADA system structure was chosen. Project of connecting separate devices is done in Wonderware Systém Platform. The next step describes procedure of interconection of parts of the cell with each other. Then was designed visualization to operate robotic cell and to illustrate its state. Whole visualization was created using Wonderware InTouch program. In conclusion thesis is reviewed.
43

Implementace protokolu ACP do operačního systému L4 / Implementation of the ACP protocol into L4 operating system

Kolarík, Tomáš January 2012 (has links)
This thesis deals with the implementation of ACP protocol which serves to manage the access for operation system based on L4 microkernel. The theoretical part of the thesis deals with methods of access management in computer networks. It focuses primarily on AAA systems which make access management possible. Furthermore it describes in detail the ACP protocol, the types of messages and their feedback. The next theoretical part is dedicated to operation systems and in particular to their architecture and services. Then we get a closer look at L4 microkernel family, their philosophy and properties. We continue with a detailed description of the L4 application interface and its ways of expansion. The practical section deals with the implemented concept of system for ACP protocol support in computers. General concept is then applied in real implementation of ACP protocol into the L4 operation system environment based on the L4 platform. To assist, I also included a detailed tutorial explaining the modeling and compilation of software for this platform. At this point we describe the methods used at the implementation and the description of particular modules and features. The end of the thesis concludes the information about the ways of testing and the implementation properties.
44

Přístupové a zabezpečovací systémy v automatizaci budov / Access and Security System in Building Automation

Troják, Pavel January 2009 (has links)
This thesis deals with automation of buildings, provides the possibility of automation in today's intelligent buildings. The issue of building automation for security and access systems is solved in details. This thesis contains the basic rules of the systems and procedure in the implementation of access and security systems. The target of this thesis is the proposal of the access and security system for buildings. Part of the thesis is also creating a model, on which will be presented the access and security system. This model will be used by the company ELMONT GROUP as a basis for dealing with contracts.
45

MBSE-basierte Produktkonfiguratoren zur Analyse der Modularisierung bei der Entwicklung modularer Baukastensysteme

Seiler, Florian, Schwede, Lea-Nadine, Krause, Dieter 03 January 2020 (has links)
Der im Zuge der Globalisierung immer stärker anwachsende Wettbewerb im Bereich produzierender Unternehmen führt zu einem kontinuierlichen Wettlauf um stetig kürzer werdende Produktionslaufzeiten. Aufgrund dessen ist eine kontinuierliche Spezialisierung mit produktspezifischen Fertigungssystemen der Akteure am Markt zu verzeichnen, die direkt zu einer erhöhten Nachfrage von Sondermaschinen führt (Krause 2018). Diese geforderte Spezialisierung lässt eine interne Standardisierung für die Hersteller kaum zu und führt zu einer extrem hohen Variantenvielfalt, deren Beherrschung eine der Kernaufgaben bei der Sicherstellung der Wettbewerbsfähigkeit darstellt. Insbesondere große Produktstrukturen sind aufgrund der anfallenden Datenmenge und dem resultierenden, hohen Grad an Verknüpfungen schwierig zu verwalten (Blees 2011). Eine Möglichkeit, die interne Vielfalt bei einer gleichbleibenden externen Vielfalt zu reduzieren und somit den enormen Umfang der Produktarchitektur und deren Folgekosten einzuschränken, bietet die Modularisierung (Krause 2018). Die Entwicklung von modularen Produktstrukturen eröffnet mittels entsprechender Standardisierung die Möglichkeit, durch Modul-, Plattform-, und Baukastenentwicklung den Zielkonflikt zwischen Produktkosten und -vielfalt zu lösen (Ehrlenspiel 2009). Ein solcher Baukasten wird als notwendiges Mittel zur Beherrschung der Vielfalt betrachtet [...] Ein Ansatz zur Lösung dieser Problemstellung ist in der Literatur durch die Verwendung von PLM(Product-Lifecycle-Management)-Systemen beschrieben. Ein entsprechendes PLM-System soll die im Unternehmen existierende Daten- und Softwarestruktur verbinden und als Single-Source of Truth (Riesener 2017) fungieren, um die Konsistenz der Modelle zu gewährleisten. Allerdings wird gerade bei der Verwendung von Modellen bei der Schaffung und Verwaltung der Produktarchitektur deutlich, dass ein PLM-System hierzu nicht vollumfänglich dazu in der Lage ist, als einheitlicher Datenstamm zu fungieren. Hierbei ist die Ontologie, die Verwendung „einheitlicher Vokabeln“ (Kaufmann et al. 2014) zwischen den Systemen, um z. B. eine Konsistenzprüfung bei der Konfiguration zu implementieren, eine nicht zu unterschätzende Herausforderung bei der Umsetzung auf Basis eines reinen PLM-Systems. Wie in diesem Beitrag beschrieben wird, lässt sich diese Lücke mithilfe des MBSE (Model-Based Systems Engineering) schließen. [... aus der Einleitung]
46

Wasserhaushaltsschichten als Bestandteil von Deponieoberflächenabdichtungssystemen

Müller, Mario 24 June 2011 (has links)
Das Wechselspiel Boden-Pflanze und die damit verbundenen Wassergehaltsänderungen im Boden bestimmen die Funktionalität einer Wasserhaushaltsschicht. Untersuchungen an der Lysimeterstation Bautzen/Nadelwitz machen deutlich, dass vielfältige Faktoren (z. B. nFK, Durchwurzelungstiefe) die Mächtigkeit einer Wasserhaushaltsschicht bestimmen. Der Bodeneinbau mit einem Verdichtungsgrad von 90% - 92% Proctordichte gewährleistet ein setzungsstabiles Korngerüst unter Gewährleistung der geforderten nFK und LK. Durch die Erweiterung des Feinbodenartendreiecks mit den Ebenen „Durchwurzelung“, „nutzbare Feldkapazität“ und „Standsicherheit“ wird eine fachübergreifende Eignungsbeurteilung von Böden ermöglicht. Die wasserhaushaltspezifische Anwendung des Dreiecks der Phasenzusammensetzung nach RUDERT erlaubt die Ausweisung von Schwankungsbreiten bzgl. der Einbaukenngrößen, ohne Abweichungen von den geforderten bodenphysikalischen Anforderungen an eine Wasserhaushaltsschicht hinnehmen zu müssen.
47

Governing for Flood Resilience in Urban Stream Corridors: Lessons from public participation in the Ramnadi corridor

Gote, Nakul Nitin 09 October 2019 (has links)
Urbanization coupled with the lack of space has led to soil sealing and encroachment upon stream corridors in many cities the world over. This has caused not just the degradation of the riparian ecosystem, but has also increased the frequency and intensity of flash flooding. India is one of the countries worst affected by urban floods. To manage flood risk, especially in the case of rain-fed urban streams, not just the government but also the public needs to be engaged in the management of the stream corridor. In this context of flood risk management, the resilience concept is increasingly being applied. It revisits some fundamental notions conventionally associated with viewing and managing floods, beginning by acknowledging that floods are natural and unavoidable, and resilience, not stability is the desirable quality. This research aims to study how governance attributes like public participation can enhance flood resilience. To this end, relevant literature on resilience and governance has been studied followed by a study of the events surrounding the flooding of the Ramnadi stream corridor in Pune city through policy analysis, data derived from documents and maps, and through semi-structured interviews with stakeholders like locals, experts, activists and civic authorities. Categorization and meaning interpretation of relevant data has enabled an analysis of the governance structure for the Ramnadi corridor using a causal loop diagram. The nodes, linkages and feedback loops in this diagram have been studied to understand how public participation affects resilience characteristics. Findings of this investigation along with draft recommendations for specific actors were presented to stakeholders in a validation workshop. Implications of the results on the theories of flood resilience, governance and public participation have been examined which has enabled their analytic generalization. General policy recommendations have been based on this. Subsequently, recommendations which promote systems approach based public participation and systems thinking in the governance of social-ecological systems have been made.:Table of Contents i List of figures iv List of tables vi Abbreviations vi Definitions vii 1 Introduction: Urban Floods, Urban Causes 1 1.1 Urban flood risk in India 3 1.2 Flooding in urban stream corridors 5 1.3 Rationale and aims of the research 8 1.4 Structure of the document 9 2 Theoretical and Conceptual Framework 13 2.1 Flood risk management 15 2.1.1 Towards a systems approach 16 2.2 Social-ecological systems 17 2.2.1 The stream corridor as a social-ecological system 17 2.3 Resilience 22 2.3.1 From ecological resilience to social-ecological resilience 23 2.3.2 Characteristics of resilience 24 2.4 Resilience in the light of other prevalent concepts for flood risk management 29 2.5 Flood Resilience 30 2.5.1 Flood resistance vs flood resilience 31 2.6 Governance 32 2.6.1 Resilience building attributes of governance 33 2.6.2 The Resilience characteristics vs. Governance attributes matrix 36 2.6.3 Special focus: Public participation 37 2.7 Research Questions 44 2.8 Conclusions from the theoretical and conceptual study 45 3 Research design and methods 47 3.1 Overall research design 48 3.1.1 The case study approach 51 3.1.2 Sampling of the case study 54 3.1.3 Boundaries of the case study 56 3.2 Data collection methods 57 3.2.1 Why interviews? 57 3.2.2 Interviewing techniques 58 3.3 Data analysis 61 3.3.1 Coding and Categorization 63 3.3.2 Meaning interpretation: 64 3.3.3 Causal loop diagram 65 3.3.4 Validation of the results and recommendations 66 3.4 Concluding remarks on the adopted research design and methods 67 4 The Ramnadi corridor: A Social-Ecological System 69 4.1 Ramnadi in context 70 4.2 A journey along the Ramnadi 75 4.2.1 Section 1: Ramnadi at the source 77 4.2.2 Section 2: Ramnadi in Bhukum 79 4.2.3 Section 3: Ramnadi between Bhukum and Pune Municipal Corporation limits 84 4.2.4 Section 4: Ramnadi in Bavdhan 87 4.2.5 Section 5: Ramnadi between the Pashan Lake and its confluence with the Mula River 91 4.3 Conclusion after the Ramnadi corridor reconnaissance 93 5 Changes in flood governance and observations from the case study 95 5.1 The history of local governance in India 96 5.2 Institutional framework for urban flood management in India 97 5.3 Flood governance and participation in the stream corridors of PunePune 98 5.3.1 The Ramnadi 98 5.3.2 The Devnadi 103 5.4 Remarks on the changes in flood governance seen in the case study 105 6 Understanding the causal links between governance attributes and flood resilience 107 6.1 The need for a Causal Loop Diagram 108 6.2 Causal Loop Diagram 109 6.2.1 Use of Causal Loop Diagram in this Thesis 109 6.2.2 The importance of identifying archetypes 111 6.2.3 Explanation of the causal loop diagram of governance of the Ramnadi corridor 113 6.2.4 Understanding the implications of change in the governance structure between 2010 and 2016 on flood resilience 141 6.3 The importance of public participation for flood resilience 142 6.3.1 Public participation promotes self-organization 142 6.3.2 Public participation increases the adaptive capacity through promotion of learning 142 6.3.3 Public participation increases robustness 143 6.3.4 Public participation increases redundancy 143 6.3.5 Public participation can increase resilience by boosting other governance attributes 143 6.3.6 Some emerging ideas on complex systems and their implications for public participation 145 6.4 Benefits of systems thinking and of the causal loop diagram for public participation 147 6.5 Conclusions from the causal loop diagram based study 149 7 Towards flood resilience through public participation 151 7.1 Continuous public participation and event-based public participation 153 7.1.1 The need for continuous public participation 154 7.1.2 Disadvantages of continuous public participation 158 7.2 Institutional recommendations for continuous public participation 158 7.2.1 Municipal Corporations and other urban local development bodies 158 7.2.2 Schools: 164 7.2.3 NGOs: 166 7.2.4 Ward Councils: 167 7.3 Conclusion 169 8 Epilogue: Discussion and Avenues for Further Research 171 8.1 Answering the research questions in the course of this research 172 8.2 Key lessons 173 8.3 Theoretical contribution to governance, public participation and resilience 174 8.3.1 Interplay between governance attributes 174 8.3.2 A new paradigm for classification of public participation 175 8.3.3 Systems approach for social-ecological resilience 175 8.4 Achieving the Sustainable Development Goals of the UN 176 8.5 Limitations of the research 176 8.6 Avenues for further research 177 9 References 179 10 Appendices 193
48

DYNAMICS OF LARGE ARRAY MICRO/NANO RESONATORS

Borra, Chaitanya 15 July 2020 (has links)
No description available.
49

Dynamical Systems in Categories

Behrisch, Mike, Kerkhoff, Sebastian, Pöschel, Reinhard, Schneider, Friedrich Martin, Siegmund, Stefan 09 December 2013 (has links)
In this article we establish a bridge between dynamical systems, including topological and measurable dynamical systems as well as continuous skew product flows and nonautonomous dynamical systems; and coalgebras in categories having all finite products. We introduce a straightforward unifying definition of abstract dynamical system on finite product categories. Furthermore, we prove that such systems are in a unique correspondence with monadic algebras whose signature functor takes products with the time space. We substantiate that the categories of topological spaces, metrisable and uniformisable spaces have exponential objects w.r.t. locally compact Hausdorff, σ-compact or arbitrary time spaces as exponents, respectively. Exploiting the adjunction between taking products and exponential objects, we demonstrate a one-to-one correspondence between monadic algebras (given by dynamical systems) for the left-adjoint functor and comonadic coalgebras for the other. This, finally, provides a new, alternative perspective on dynamical systems.:1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2 Preliminaries and Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.1 Preliminaries related to topology and measure theory . . . . . . . . 4 2.2 Basic notions from category theory . . . . . . . . . . . . . . . . . . . . . . . 8 2.3 Classical dynamical systems theory . . . . . . . . . . . . . . . . . . . . . . 23 3 Dynamical Systems in Abstract Categories . . . . . . . . . . . . . . . . . . 30 3.1 Monoids and monoid actions in abstract categories . . . . . . . . . . 31 3.2 Abstract dynamical systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.3 Nonautonomous dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 4 Dynamical Systems as Algebras and Coalgebras . . . . . . . . . . . . . .38 4.1 From monoids to monads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 4.2 From abstract dynamical systems to monadic algebras . . . . . . . 48 4.3 Connections to coalgebras . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 4.4 Exponential objects in Top for locally compact Hausdorff spaces . . 52 4.5 (Co)Monadic (co)algebras and adjoint functors . . . . . . . . . . . . . .56
50

Systémový přístup k financování zdravotnictví / A Systems Approach to Health Care Financing

Jankůj, Miroslav January 2010 (has links)
This diploma thesis deals with the Czech healthcare system. Healthcare is generally reffered to as system but not always healthcare problems are solved systematically. Therefore systems theory, theory of complex adaptive systems and other notions, that are often used in healthcare, were described in this thesis. The objective of this thesis was analysis of impacts of patient's financial participation (20 %, 25 % and 30 %) on health care to their financial situation in the complex adaptive healthcare system. In this thesis four indicators were used -- poverty line, household subsistence spending, impoverished households, catastrophic health expenditure. The World Health Organization defined this indicators for World Health Survey in different countries. The indicators were applied to a sample of Czech households and some impacts of increased participation were calculated. It results from this calculation that the increased participation of households has virtually only small impacts to their financial situation. By the indicators of poverty just few households would be on the poverty line. Nevertheless, this results aren't generalized to the whole Czech population. With this indicators we should further work and develop them in order that they could serve as tool to evaluation of state's intervetion into healthcare system.

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