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Almeida, Cardoso F. J. "A distributed system for laboratory process automation." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329584.
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Lee, Szer-Ming. "A component-based distributed control paradigm for manufacturing automation system." Thesis, Loughborough University, 2004. https://dspace.lboro.ac.uk/2134/33872.
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Manufacturing enterprises need to have agile manufacturing automation systems that can be responsive to changes in demand and operate efficiently within the context of a global business economy. Manufacturing automation systems that possess the capabilities to support flexibility, reconfigurability and reusability would enable enterprises to have a competitive edge in their markets. However, traditional approaches to manufacturing automation systems development and implementation are typically rigid in nature and thus do not provide the capabilities to adequately support the required levels of agility. This thesis has specified and developed a paradigm for developing and implementing an agile manufacturing automation system.
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Wang, Xiaolong. "A Secure Computing Platform for Building Automation Using Microkernel-based Operating Systems." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7589.
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Building Automation System (BAS) is a complex distributed control system that is widely deployed in commercial, residential, industrial buildings for monitoring and controlling mechanical/electrical equipment. Through increasing industrial and technological advances, the control components of BAS are becoming increasingly interconnected. Along with potential benefits, integration also introduces new attack vectors, which tremendous increases safety and security risks in the control system. Historically, BAS lacks security design and relies on physical isolation and "security through obscurity". These methods are unacceptable with the "smart building" technologies. The industry needs to reevaluate the safety and security of the current building automation system, and design a comprehensive solution to provide integrity, reliability, and confidentiality on both system and network levels.
This dissertation focuses on the system level in the effort to provide a reliable computing foundation for the devices and controllers. Leveraged on the preferred security features such as, robust modular design, small privilege code, and formal verifiability of microkernel architecture, this work describes a security enhanced operating system with built-in mandatory access control and a proxy-based communication framework for building automation controllers. This solution ensures policy-enforced communication and isolation between critical applications and non-critical applications in a potentially hostile cyber environment.
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Panjaitan, Seno Darmawan. "Development process for distributed automation systems based on elementary mechatronic functions." Aachen Shaker, 2007.
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Clabough, Douglas M. "An electronic calendar system in a distributed UNIX environment." Thesis, Kansas State University, 1986. http://hdl.handle.net/2097/9906.
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Franco, Nicola. "Distributed Observer Analysis and Design." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19642/.
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A Distributed observer design is described for estimating the state of a continuous-time, input free, linear system. This thesis explains how to construct the local estimators, which comprise the observer inputs and outputs, and it is shown which are the requirements to deal with this structure. Every agent senses an output signal from the system and distributes it across a fixed-time network to its neighbors. The information flow increases the capability of each agent to estimate the state of the system and uses collaboration to improve the quality of data. The proposed solution has several positive features compared to recent results in the literature, which include milder assumptions on the network connectivity and the maximum dimension of the state of each observer does not exceed the order of the plant. The conditions are reduced to certain detectability requirements for each cluster of agents in the network, where a cluster is identified as a subset of agents that satisfy specific properties. Instead, the dimension of each observer is reduced to the number of possible observable states of the system, collected by the agent and by the neighbors.
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Ding, Fei. "Smart Distribution System Automation: Network Reconfiguration and Energy Management." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1417291114.
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Mukkavaara, Jani. "Structures for supporting BIM-based automation in the design process." Licentiate thesis, Luleå tekniska universitet, Industriellt och hållbart byggande, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70412.
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During recent decades the advent of IT in the construction industry has prompted a gradual shift from manual paper-based processes to computer-aided design and production. In this shift there has been an increasing interest in the application of building information modelling (BIM) for the overall management of information throughout the lifecycle of a building. By implementing BIM and automating the workflows within, decreased time spent on engineering tasks and an increased focus on building performance could be achieved during the design process. Due to the complexity of the design process it is rare that a single BIM application can manage all the activities that are present. This puts pressure on the coupling of multiple applications, tools, and information. The challenges that this poses on interoperability and information exchange has received a wealth of attention in research however it is still argued that many of these operations require manual input. Automating parts of a BIM-based workflow is facilitated by the possibilities that exists for exchanging information and controlling the flow of information. This implies that not only do we need to understand this on a data level, but also that we understand how the system and information structures can be managed to enable this. The purpose of this thesis was to investigate how structures could be applied on both a system and information level to support automation within a BIM-based design process, and more specifically how these structures could be used to overcome some of the challenges of information exchange. Three studies were conducted to explore different methods and their potential in achieving automated workflows. The findings of these studies were then analysed against a theoretical framework based on structures of systems and information. The results show that choosing a distributed method for structuring systems allows for the coupling of multiple software, tools, and information without the need for a single shared schema. The critical component of the distributed system structure is a middleware which is responsible for controlling the flow of information. It is the middleware that when implemented allows for the management of multiple sources of information, each with their corresponding schemas. The results also showed that information which travels between the components of the distributed system can be structured according to their relationships to provide the foundation for a mapping. This structure enables the decomposition of information that can be used to transfer information only relevant to the current activity. When applied this aids to resolve the coupling of information at each activity in an automated BIM-based workflow.
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Mather, Jonathan, and Nancy Shaw. "RANGE SAFETY CASE STUDY: WESTERN RANGE CENTRALIZED TELEMETRY PROCESSING SYSTEM (WR CTPS), A LARGE DISTRIBUTED GROUND SYSTEM." International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604505.
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ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada<br>This paper presents a case study of the Western Range Centralized Telemetry Processing Subsystem (WR CTPS). This system was developed by Lockheed Martin Integrated Systems and Global Services and L-3 Communications Telemetry-West as part of the Range Standardization and Automation (RSA) IIA program. Requirements included real-time simultaneous acquisition of 16 PCM streams at rates of up to 30M bits per second; real-time processing; and data display on workstations connected over a gigabit Ethernet network. This system is designed for range safety and needs to be fault-tolerant while maintaining 100 percent data availability in the event of a single failure during an operation. The development of such a system demanded a rigorous Systems Engineering approach to ensure the successful upgrade and deployment onto the range infrastructure. This case study provides an overview of the system technical requirements and its architecture. The summary presents challenges encountered during the development and lessons learned while meeting them.
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畢天姝 and Tianshu Bi. "Distributed intelligent system for on-line fault section estimation oflarge-scale power networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42576714.
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Kaur, Navjot. "A service-oriented approach to embedded component-based manufacturing automation." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/9445.
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This thesis is focused on the application of Component-Based (CB) technology to shop floor devices using a Service Oriented Architecture (SOA) and Web Services (WS) for the purpose of realising future generation agile manufacturing systems. The environment of manufacturing enterprises is now characterised by frequently changing market demands, time-to-market pressure, continuously emerging new technologies and global competition. Under these circumstances, manufacturing systems need to be agile and automation systems need to support this agility. More specifically, an open, exible automation environment with plug and play connectivity is needed. Technically, this requires the easy connectivity of hardware devices and software components from different vendors. Functionally, there is a need of interoperability and integration of control functions on different hierarchical levels ranging from field level to various higher level applications such as process control and operations management services. A potential solution is to realise a modular and reconfigurable automation system, based on a platform of reusable components; while simultaneously reducing the number of unique components. For designing such reusable components, a component-based technology has been used in current thesis. The automation components created are active and distributed entities interacting through their data, event and service ports. To communicate these entities, this thesis focuses on applying SOA and WS at device level. SOA and WS have already been proven successful in linking business applications. If SOA can be applied at shop floor using the embedded devices, it can enable entirely new automation architecture based on peer-to-peer interactions between autonomous devices. The adoption of this SOA-WS approach at shop floor level would enable a seamless integration of higher level business applications and shop- floor level system. This will also provide a loosely coupled message-oriented service in embedded device networks and geographically distributed automation system. SOA can be implemented using Web Services on the embedded devices, which will provide even greater exibility and interoperability because WS is platform neutral. This SOA-WS approach will enable end users to operate and maintain the supplied system easily. A key aim of this thesis is to examine if the adoption of SOA-WS at the embedded control devices can provide the same level of message speed and reliability as the current control systems. It is expected that the desired distributed, loosely coupled and reconfigurable automation system can be formed by a network of these collaborative autonomous SOA-WS based devices using an open control platform. This approach has been experimentally evaluated both in terms of quantity and quality using various parameters involved in the design, implementation, evaluation and recon guration of SOA-WS based automation systems. This has been done using the Ford Festo test rig located at the Manufacturing System Integration Research Institute of Loughborough University. The mechanisms on this test rig represent control problems typically associated in engine assembly and handling machines. Therefore, the result of experimental studies performed on this test rig can be considered applicable to real manufacturing applications.
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Souto, Laiz de Carvalho. "Fault location in power distribution networks with distributed generation." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-28062016-151847/.
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This research presents the development and implementation of fault location algorithms in power distribution networks with distributed generation units installed along their feeders. The proposed algorithms are capable of locating the fault based on voltage and current signals recorded by intelligent electronic devices installed at the end of the feeder sections, information to compute the loads connected to these feeders and their electric characteristics, and the operating status of the network. In addition, this work presents the study of analytical models of distributed generation and load technologies that could contribute to the performance of the proposed fault location algorithms. The validation of the algorithms was based on computer simulations using network models implemented in ATP, whereas the algorithms were implemented in MATLAB.<br>Esta pesquisa apresenta o desenvolvimento e a implementação de algoritmos para localização de faltas em redes primárias de distribuição de energia elétrica que possuem unidades de geração distribuída conectadas ao longo dos seus alimentadores. Esses algoritmos são capazes de efetuar a localização de faltas utilizando registros dos sinais de tensões e correntes realizados por dispositivos eletrônicos inteligentes, instalados nas saídas dos alimentadores de distribuição, além de informações que permitam determinar os valores das cargas conectadas nesses alimentadores, características elétricas, e o estado operativo da rede de distribuição. Ademais, este trabalho apresenta o estudo de modelos analíticos de unidades de geração distribuída e de cargas que poderiam contribuir positivamente com o desempenho dos algoritmos propostos. A validação dos algoritmos foi realizada através de simulações computacionais, utilizando modelos de rede implementados em ATP e os algoritmos foram implementados em MATLAB.
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Carnevale, Guido. "Control-based Design and Analysis of Gradient-Tracking Algorithms for Distributed Quadratic Optimization." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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In this work we design an iterative distributed optimization algorithm, based on the well-known distributed gradient tracking algorithm. We show the advantages of a system theoretical approach on a distributed optimization framework in which the cost function is
given by a sum of quadratic functions. In other words, the main idea of the work consists in seeing the update equation characterizing an iterative optimization algorithm as the dynamics equation of a discrete-time system in which the decision variable plays the state
variable role. The goal of the work is to show how system and control theory tools can be used to force this state variable to the optimum of the considered cost function even in presence of disturbances and/or uncertainties. So, the design of a distributed optimization algorithm is seen as the design of a controller able to solve the set point control problem in which the reference signal is given by the optimum of the considered cost function.
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Malaviya, Anoop Kumar. "Decision mechanism, knowledge representation, and software architecture for an intelligent control system." University of Western Australia. Dept. of Electrical and Electronic Engineering, 1998. http://theses.library.uwa.edu.au/adt-WU2006.0127.
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[Truncated abstract] This thesis analyses the problem of Intelligent Control for large industrial plants and suggests a hierarchical, distributed, object-oriented architecture for Intelligent Control. The architecture is called MLIAC (Multi Level Intelligent Adaptive Control) Architecture. The MLIAC architecture is inspired by biological control systems (which are flexible, and are capable of adapting to unstructured environments with ease) and the success of the distributed architecture SCADA (Supervisory Control and Data Acquisition) Systems. The MLIAC Architecture structures the decision and control mechanism for the real-time properties namely safety, liveliness, and timeliness . . . In addition, three case studies have been reported. The case studies cover the control of a Flexible Manufacturing System and the Mine Products Quality Control. The results show that MLIAC Knowledge Representation model meets the requirements of the Roth-Hayes benchmark regarding Knowledge Representation. The decisions taken are logically tractable. The software architecture is effective and easily implemented. The actual performance has been found to depend upon a number of factors discussed in this thesis. For the specification and design of Potline MLIAC software, a CASE package ("Software Through Pictures") has been used. The Potline MLIAC software has been developed using C⁄C++, SQL, 4 GL and RDBMS based on a Client-Server model. For computer simulation the Potline MLIAC software has been integrated with the MATLAB⁄SIMULINK package.
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Lanzarini, Matteo. "Distributed optimization methods for cooperative beamforming in satellite communications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23246/.
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This thesis analyzes various beamforming techniques and theories of space information networking (SIN), with the aim of merging and using them in real application. We propose then two algorithm to solve two different problem linked to satellites and beamforming. The first one show a cluster of satellites that performs collaborative beamforming to reach an Earth user, while reducing interference in secondary directions. Then we consider a problem for hybrid satellite-terrestrial relay networks (HSTRNs), where multiple geostationary satellites transmit signals to multiple Earth terminal, with the help of multiple single-antenna relays.
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Zaitouni, Wael K. "Applied Real-Time Integrated Distributed Control Systems: An Industrial Overview and an Implemented Laboratory Case Study." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc862854/.
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This thesis dissertation mainly compares and investigates laboratory study of different implementation methodologies of applied control systems and how they can be adopted in industrial, as well as commercial, automation applications. Namely the research paper aims to assess or evaluate eventual feedback control loops' performance and robustness over multiple conventional or state-of-the-art technologies in the field of applied industrial automation and instrumentation by implementing a laboratory case study setup: the ball on beam system. Hence, the paper tries to close the gap between industry and academia by: first, conducting a historical study and background information of main evolutional and technological eras in the field of industrial process control automation and instrumentation. Then, some related basic theoretical as well as practical concepts are reviewed in Chapter 2 of the report before displaying the detailed design. After that, the next Chapter, analyses the ball on beam control system problem as the case studied in the context of this research through reviewing previous literature, modeling and simulation. The following Chapter details the proposed design and implementation of the ball on beam case study as if it is under the introduced distributed industrial automation architecture. Finally, Chapter 5 concludes this work by listing several points leaned, remarks, and observations, and stating possible development and the future vision of this research.
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Trentesaux, Damien. "Conception d'un système de pilotage distribué, supervisé et multicritère pour les systèmes automatisés de production." Phd thesis, Grenoble INPG, 1996. http://www.theses.fr/1996INPG0030.
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Le cadre de travail dans lequel s'inscrit cette thèse porte sur le développement d'une structure de pilotage prenant en compte simultanément les contraintes prévisionnelles et les contraintes réelles du système de production. Ces premières s'expriment en terme d'objectifs globaux et les secondes en terme de réactivité et de flexibilité. Plusieurs études ont montré les possibilités offertes par la structure distribuée pour absorber les fonctionnements dégradés. L'objectif de ce mémoire est d'étendre et de compléter la structure de pilotage de Tchako afin: , de permettre la prise en compte de la notion d'objectif global, , d'accroître la capacité intrinsèque de réactivité de l'approche distribuée. Nous montrons d'une part que l'intégration de la notion d'objectif global peut être obtenue par l'adjonction d'un niveau de supervision au modèle de Tchako. D'autre part, afin de conserver un niveau de réactivité satisfaisant, nous montrons qu'un compromis efficace entre les besoins en termes de réactivité et de gestion prévisionnelle (objectifs globaux) consiste à ordonnancer une partie des opérations à réaliser (ordonnancement partiel). Nous élaborons une liste des différentes approches possibles concernant les opérations (ou les ressources de production) à ordonnancer, et justifions une approche par ordonnancement partiel d'une ressource critique. Nous désignons la structure de pilotage correspondante sous le terme de pilotage hybride. L'accroissement de la capacité intrinsèque de réactivité résulte de la conception et du développement d'une structure de communication décomposée en deux niveaux, intégrant chacun une gestion de la robustesse. Ce point constitue une conceptualisation et une extension de la structure de communication de Tchako. Un autre point porte sur le développement d'un module de gestion de contraintes dynamiques portant sur le processus de fabrication. Par ailleurs, l'étude des processus de décision dans un cadre de pilotage temps-réel et distribué montre que les décisions sont de nature multicritère. L'étude de faisabilité que nous présentons a porté sur l'intégration d'une approche multicritère au niveau des processus décisionnels, prenant en compte les contraintes imposées au niveau du pilotage hybride. Elle a mis en évidence le faible niveau de structuration des processus décisionnels et conduit à analyser les possibilités d'intégration de l'opérateur humain via un système interactif d'aide multicritère à la décision<br>A distributed production activity control system has been developed to solve several problems inherent in the inflexibility of classic centralized production activity control systems. The distributed approach implies local decision makings and real time control for task allocations. This forbids correct forecast on critical information such as time cycle for each manufacturing order, meaning a miss of viability for industrial application. The aim of our work is to provide a structure which takes advantage of both extrema and which is able to support just-in-time concepts: the hybrid production activity control structure. The hybrid approach uses the notion of bottleneck and non bottleneck resources and is based on the distributed control structure developed in the laboratory. The bottleneck is the only resource scheduled. It forces the synchronicity of the whole production structure because of its characteristics. This paper evaluates the relative performances of the three control structures (centralized, distributed and hybrid) through theoretical discussions and practical examples from a simplified industrial case study
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Mahmoud, Thair. "Optimal power generation in microgrids using agent-based technology." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/599.
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The existing power grids that form the basis of the respective electrical power infrastructures for various states and nations around the world, are expected to undergo a period of rapid change in the near future. The key element driving this change is the emergence of the Smartgrid. The Smartgrid paradigm represents a transition towards an intelligent, digitally enhanced, two-way power delivery grid. The aim of the Smartgrid is to promote and enhance the e_cient management and operation of the power generation and delivery facilities, by incorporating advanced communications, information technology, automation, and control methodologies into the power grid proper. Smartgrid's are currently an active topic for research, where the research is strongly focused on developing new technologies such as: demand response, power generation management, pricing modelling and energy markets participation, power quality, and self-healing scenarios. In recent times, in both the United States of America and Europe, many new projects have begun which are specifically directed towards developing “Smartgrid” technologies. In Australia, the Federal Government has recently initiated funding plans to promote the commercialisation of renewable energy. In order to exploit these developments, Edith Cowan University (ECU); which is a High Voltage (HV) customer for the major utility network of Western Australia, and which owns its own transformers and Low Voltage (LV) network; is planning to integrate renewable energy suppliers within its LV network.
The aim of this research is to introduce a smart decision making system, which can manage the operation of disparate power generation sources installed on a LV network (microgrid); such as that owned by ECU on its campuses. The proposed energy management system is to gather data in real-time, and it must be capable of anticipating and optimising energy needs for each operational scenario that the microgrid might be expected to experience. The system must take into account risk levels, while systematically favouring low economic and environmental costs. A management system application, based on autonomous and distributed controllers, is investigated in a virtual environment. The virtual environment being a full-scale simulation of ECU's microgrid; with solar panels, wind turbines, storage devices, gas gen-sets, and utility supply. Hence the simulation studies were conducted on the basis of realistic demand trends and weather conditions data.
The major factors for reducing the cost of generation in the case study, were identified as being: 1) demand forecasting; 2) generation scheduling; 3) markets participation; and 4) autonomous strategies configuration, which is required to cope with the unpredictable operation scenarios in LV networks. Due to the high uncertainty inherent within the operational scenarios; an Artificial Intelligence (AI) deployment for managing the distributed sub-systems was identified as being an ideal mechanism for achieving the above mentioned objectives. Consequently it is proposed that Multi-Agent System (MAS) technology be deployed, to enable the system to respond dynamically to the unpredictable operational conditions by updating the method of analysis. The proposed system is to behave in a strategic manner when dealing with the expected operational scenarios, by aiming to achieve the lowest possible cost of power generation for the microgrid. The simulated system is based on realistic operational scenarios, which have been scaled to suit the size and type of load in the case study. The distributed intelligent modules have proven to be successful in achieving the potential benefits of the dynamic operational conditions, by minimising the cost of power generation.
The distributed intelligent modules, which form the basis of the proposed management systems, have been designed to perform the following functions:
1. Provide accurate demand forecasts through the utilisation of an AI-based adaptive demand forecasting model. The novel demand-forecast modelling technique, which was introduced to model demand in the case study, has been utilised to supply reasonably accurate demand forecasts to other stages of processing in the management system. The forecasts are generated from this model, by monitoring and controlling the forecasting error to ensure consistent and satisfactory forecasts.
2. Make optimum decisions concerning the operation of the power generators by considering the economic and the environmental costs. In order to deal with the complexity of the operational conditions, a smart and adaptive generation scheduling method was implemented for the case study. The method was primarily applied to control the charging/ discharging process of the Storage Devices (SDs) among the other generators. The proposed method aims at controlling the resources, and extracting the benefit of having an hourly based variable generation cost.
3. Integrate the microgrid into the electricity market, in order to enable the microgrid to offer its spinning and non-spinning power generation reserve as Ancillary Services (AS) to the grid. To this end, studying the operational mechanisms of the Australian market was essential prior to building the proposed market participation rules which form an integral part of the proposed management system. As a result we used the market data, by approaching the market operators to create a semi-realistic competitive market environment for our simulations. Consequently, a smart and adaptive pricing mechanism, that adapts the AS prices to the amount of electricity on offer, and the level of demand in the market has been presented.
The motivation for introducing the proposed management system, is to achieve a transition plan for current microgrids, so that they can have a commercial connection to the future Smartgrid. The results obtained in this work show that there is a signi_cant economic and environmental advantage to be gained from utilising intelligence when managing electricity generation within a power grid. As a consequence, selecting the appropriate management strategy is fundamental to the success of the proposed management system. In conclusion, modelling of the proposed strategies using MAS technology has proven to be a successful approach, and one that is able to reflect the human attitude; in making critical decisions and in reducing the cost of generation.
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Britton, Karen J. "Automation of a capacitance dilatometer using distributed control." Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/13975.
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A comprehensive and novel system of automatic control has been designed and constructed using distributed intelligence techniques to control a complex item of equipment for the measurement of linear thermal expansion over the temperature range 1.5K - 300K. The system is designed to perform its own self-calibration automatically before the experiment commences. The low temperature dllatometer developed for this research project incorporates the most sensitive length change sensor available; a three-terminal capacitance transducer. This transducer technique has been refined to resolve length changes of 10-5A and more importantly, measure length against temperature profiles to better than 10-2A. The period of time required to collect a full set of data measurements on any particular specimen was in excess of 100 hours. Forming the heart of the automated control system is an assembly of Intel MCS-Sl single chip microcontrollers connected together on a serial link consisting of a simple pair of wires. The approach has been to divide the system automation into a number of specific control tasks and to allocate a different task to each controller. The Instrument has been used as a diagnostic tool to investigate the properties of lead glasses, and in particular to study the possibility of negative thermal expansion existing at low temperatures. Thermal expansion measurements were also performed to observe the phase change within single crystals of polydiacetylene and to research into low temperature phenomena occurlng within the crystal.
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Ajmani, Sameer 1976. "Automatic software upgrades for distributed systems." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28717.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.<br>Includes bibliographical references (p. 156-164).<br>Upgrading the software of long-lived, highly-available distributed systems is difficult. It is not possible to upgrade all the nodes in a system at once, since some nodes may be unavailable and halting the system for an upgrade is unacceptable. Instead, upgrades may happen gradually, and there may be long periods of time when different nodes are running different software versions and need to communicate using incompatible protocols. We present a methodology and infrastructure that address these challenges and make it possible to upgrade distributed systems automatically while limiting service disruption. Our methodology defines how to enable nodes to interoperate across versions, how to preserve the state of a system across upgrades, and how to schedule an upgrade so as to limit service disrup- tion. The approach is modular: defining an upgrade requires understanding only the new software and the version it replaces. The upgrade infrastructure is a generic platform for distributing and installing software while enabling nodes to interoperate across versions. The infrastructure requires no access to the system source code and is transparent: node software is unaware that different versions even exist. We have implemented a prototype of the infrastructure called Upstart that intercepts socket communication using a dynamically-linked C++ library. Experiments show that Upstart has low overhead and works well for both local-area-and Internet systems.<br>by Sameer Ajmani.<br>Ph.D.
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Ştefănescu, Alin. "Automatic synthesis of distributed transition systems." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-25606.
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Akazan, Justin N'Guessan. "Contribution à l'intégration de la messagerie industrielle MMS dans les systèmes et applications temps réel et répartis." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL067N.
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Compte tenu de l'importance de la communication dans un Système Automatise (SA), le réseau MAP (Manufacturing Automation Protocol) et, en particulier, le protocole MMS (Manufacturing Message Specification) ont été développés afin de permettre la communication et la synchronisation entre des machines hétérogènes dans un SA. Bien que MMS offre des facilités de communication et de synchronisation entre taches réparties, ce protocole présente des faiblesses, notamment au niveau de la prise en compte des contraintes temporelles, alors que celles-ci sont fondamentalement importantes dans les environnements qui utilisent MMS. Par ailleurs, l'utilisation de MMS dans des environnements industriels est limitée en raison de la difficulté inhérente à l'usage de MMS. Cette thèse est une contribution à la résolution de ces problèmes. Elle est structurée en trois parties: 1. Présentation de l'importance de la communication, donc de MMS, dans les systèmes automatisés. 2. Présentation d'un outil de développement d'applications temps réel fondées sur MMS. À partir d'une spécification d'application temps réel et répartie, cet outil, baptisé MMS-Toolkit, permet de générer les services de communication MMS ainsi que les contraintes temporelles provenant de la spécification de l'application. Il permet ainsi d'automatiser, en partie, l'étape de passage d'une architecture fonctionnelle à une architecture opérationnelle. 3. Présentation d'une approche d'extension de MMS du point de vue temps réel. Il s'agit de l'intégration des contraintes de temps dans les objets, services et le protocole MMS afin de mieux prendre en compte la dimension temporelle des applications faisant appel à MMS. Les contraintes de temps exprimées sur les objets et les services n'offrent d'intérêt que si les exécutions auxquelles elles sont associées sont ordonnancées en vue de respecter ces contraintes. Ainsi l'ordonnancement temps réel de taches et de messages devient primordial pour MMS temps réel ; il est donc étudié dans cette partie. La thèse se termine par une conclusion montrant les résultats obtenus et les perspectives envisagées pour poursuivre ce travail
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Jayaraman, Usha. "Toward the development of control software for an operator interface in the distributed automation environment." Master's thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-04122010-083449/.
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Wang, Yanyan. "Automating experimentation with distributed systems using generative techniques." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219040.
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Козирка, В. Є. "Автоматизація процесів управління розподіленими командами з використанням технології чат-ботів". Master's thesis, Сумський державний університет, 2019. http://essuir.sumdu.edu.ua/handle/123456789/75935.
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У роботі проведено дослідження процесів управління в компанії ТОВ «Центр мережевих технологій ВЕБ100» (QATestLab) і сформовано вимоги до автоматизованої інформаційної системи. Виконано проектування архітектури автоматизованої інформаційної системи. Створено прототип автоматизованої інформаційної системи на основі чат-бота.<br>The master's thesis conducted research on management processes in the company "Center Network Technology WEB100" (QATestLab) and the requirements for the automated information system were composed. The architecture of the automated information system has been designed. A prototype of an automated chatbot information system has been developed.
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Kara, Mourad. "Development of distributed scheduling systems with an application to office automation." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484190.
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Ye, Lina. "Optimized diagnosability of distributed discrete event systems through abstraction." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00635695.
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Depuis plusieurs années, de nombreuses recherches ont été menées autour du diagnostic. Cependant, il est impératif de se préoccuper dès la phase de conception d'un système des objectifs de diagnostic à atteindre. Aussi, de nombreux travaux se sont intéressés à analyser et à caractériser les propriétés de la diagnosticabilité d'un système. La diagnosticabilité est la propriété d'un système garantissant qu'il génère des observations permettant de détecter et discriminer les fautes en temps fini après leur occurrence.Le sujet de cette thèse porte sur les méthodes permettant d'établir les propriétés de la diagnosticabilité des systèmes à événements discrets dans le cadre distribué, sans construction du modèle global du système. Ce cadre est de première importance pour les applications réelles : systèmes naturellement distribués, systèmes trop complexes pour traiter leur modèle global, confidentialité des modèles locaux les uns par rapport aux autres. L'analyse de la diagnosticabilité de tels systèmes distribués se fonde sur des opérations de synchronisation des modèles locaux, par les observations et les communications. D'abord, nous étudions comment optimiser cette analyse de la diagnosticabilité en faisant abstraction de l'information nécessaire et suffisante à partir des objets locaux pour décider la diagnosticabilité globale. L'efficacité de l'algorithme peut être grandement améliorée par la synchronisation des objets locaux et abstraits en comparaison avec celle des objets locaux et non abstraits.Ensuite, nous proposons, dans le cadre distribué, l'algorithme de la diagnosticabilité de motifs d'événements particuliers a priori inobservables dans les systèmes. Ces motifs peuvent être simplement l'occurrence, brutale ou graduelle, d'une faute permanente ou transitoire, plusieurs occurrences d'une faute, plusieurs fautes en cascade, etc. Dans le cadre distribué, la reconnaissance du motif d'événements s'effectue d'abord progressivement dans un sous-système et ensuite la diagnosticabilité de ce motif peut être déterminée par la méthode abstraite et distribuée. Nous prouvons la correction et l'efficacité de notre algorithme à la fois en théorie et en pratique par la mise en œuvre de l'implémentation sur des exemples.Finalement, nous étudions le problème de la diagnosticabilité dans les systèmes distribués avec composants autonomes, où l'information observable est distribuée au lieu d'être centralisée comme jusqu'alors. En d'autres termes, chaque composant ne peut appréhender que ses propres événements observables. Nous donnons la définition de la diagnosticabilité conjointe. Et puis nous discutons de l'indécidabilité de diagnosticabilité conjointe dans le cas général, c'est à dire, les événements de communication ne sont pas observables, avant de proposer un algorithme pour tester sa condition suffisante. De plus, nous obtenons également un résultat de décidabilité et de l'algorithme lorsque les communications sont observables.
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Qin, Ming Melvin. "Automatic generation of performance models of distributed application systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ27066.pdf.
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Qin, Ming Melvin Carleton University Dissertation Engineering Systems and Computer. "Automatic generation of performance models for distributed application systems." Ottawa, 1998.
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Puchol, Carlos Miguel. "An automation-based design methodolgy [sic] for distributed, hard real-time systems /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Gastin, Paul. "Un modele distribue." Paris 7, 1987. http://www.theses.fr/1987PA077072.
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Le modele presente s'inspire de la theorie des langages. Son originalite est le refus de representer le parallelisme par intercalage des actions concurrentes. Les idees fortes reprises dans ce travail sont issues des langages csp et estelle. Il s'agit principalement de l'independance totale des processus en dehors des synchronisations, ces dernieres etant des rendez-vous. Un element du modele distribue sera en consequence un vecteur d'histoires (un four chaque processus) et un ensemble de synchronisations
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Capiluppi, Marta <1978>. "Fault tolerance in large scale systems: hybrid and distributed approaches." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/343/1/main_thesis.pdf.
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Capiluppi, Marta <1978>. "Fault tolerance in large scale systems: hybrid and distributed approaches." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/343/.
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Yao, Lisha. "Distributed Consensus, Optimization and Computation in Networked Systems." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404555/.
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In the first part of this thesis, we propose a distributed consensus algorithm under multi-layer multi-group structure with communication time delays. It is proven that the consensus will be achieved in both time-varying and fixed communication delays. In the second part, we study the distributed optimization problem with a finite-time mechanism. It is shown that our distributed proportional-integral algorithm can exponentially converge to the unique global minimizer when the gain parameters satisfy the sufficient conditions. Moreover, we equip the proposed algorithm with a decentralized algorithm, which enables an arbitrarily chosen agent to compute the exact global minimizer within a finite number of time steps, using its own states observed over a successive time steps. In the third part, it is shown the implementation of accelerated distributed energy management for microgrids is achieved. The results presented in the thesis are corroborated by simulations or experiments.
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Niemelä, Eila. "A component framework of a distributed control systems family /." Espoo [Finland] : Technical Research Centre of Finland, 1999. http://www.vtt.fi/inf/pdf/publications/1999/P402.pdf.
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Hallgren, Dan, and Håkan Skog. "Distributed Fault Diagnosis for Networked Embedded Systems." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5229.
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<p>In a system like a Scania heavy duty truck, faultcodes (DTCs) are generated and stored locally in the ECUs when components, e.g. sensors or actuators, malfunction. Tests are run periodically to detect failure in the system. The test results are processed by the diagnostic system that tries to isolate the faulty components and set local faultcodes.</p><p>Currently, in a Scania truck, local diagnoses are only based on local diagnostic information, which the DTCs are based upon. The diagnosis statement can, however, be more complete if diagnoses from other ECUs are considered. Thus a system that extends the local diagnoses by exchanging diagnostic information between the ECUs is desired. The diagnostic information to share and how it should be done is elaborated in this thesis. Further, a model of distributed diagnosis is given and a few distributed diagnostic algorithms for transmitting and receiving diagnostic information are presented.</p><p>A basic idea that has influenced the project is to make the diagnostic system scalable with respect to hardware and thereby making it easy to add and remove ECUs. When implementing a distributed diagnostic system in networked real-time embedded systems, technical problems arise such as memory handling, process synchronization and transmission of diagnostic data and these will be discussed in detail. Implementation of a distributed diagnostic system is further complicated due to the fact that the isolation process is a non deterministic job and requires a non deterministic amount of memory.</p>
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Johansson, Björn. "On Distributed Optimization in Networked Systems." Doctoral thesis, KTH, Reglerteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-9801.
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Numerous control and decision problems in networked systems can be posed as optimization problems. Examples include the framework of network utility maximization for resource allocation in communication networks, multi-agent coordination in robotics, and collaborative estimation in wireless sensor networks (WSNs). In contrast to classical distributed optimization, which focuses on improving computational efficiency and scalability, these new applications require simple mechanisms that can operate under limited communication. In this thesis, we develop several novel mechanisms for distributed optimization under communication constraints, and apply these to several challenging engineering problems. In particular, we devise three tailored optimization algorithms relying only on nearest neighbor, also known as peer-to-peer, communication. Two of the algorithms are designed to minimize a non-smooth convex additive objective function, in which each term corresponds to a node in a network. The first method is an extension of the randomized incremental subgradient method where the update order is given by a random walk on the underlying communication graph, resulting in a randomized peer-to-peer algorithm with guaranteed convergence properties. The second method combines local subgradient iterations with consensus steps to average local update directions. The resulting optimization method can be executed in a peer-to-peer fashion and analyzed using epsilon-subgradient methods. The third algorithm is a center-free algorithm, which solves a non-smooth resource allocation problem with a separable additive convex objective function subject to a constant sum constraint. Then we consider cross-layer optimization of communication networks, and demonstrate how optimization techniques allow us to engineer protocols that mimic the operation of distributed optimization algorithms to obtain an optimal resource allocation. We describe a novel use of decomposition methods for cross-layer optimization, and present a flowchart that can be used to categorize and visualize a large part of the current literature on this topic. In addition, we devise protocols that optimize the resource allocation in frequency-division multiple access (FDMA) networks and spatial reuse time-division multiple access (TDMA) networks, respectively. Next we investigate some variants of the consensus problem for multi-robot coordination, for which it is usually standard to assume that agents should meet at the barycenter of the initial states. We propose a negotiation strategy to find an optimal meeting point in the sense that the agents' trajectories to the meeting point minimize a quadratic cost criterion. Furthermore, we also demonstrate how an augmented state vector can be used to boost the convergence rate of the standard linear distributed averaging iterations, and we present necessary and sufficient convergence conditions for a general version of these iterations. Finally, we devise a generic optimization software component for WSNs. To this end, we implement some of the most promising optimization algorithms developed by ourselves and others in our WSN testbed, and present experimental results, which show that the proposed algorithms work surprisingly well.<br>QC 20100813
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吳建雄 and Jianxiong Wu. "A parallel distributed processing system for machine recognition of speech signals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31232887.
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Wu, Jianxiong. "A parallel distributed processing system for machine recognition of speech signals /." [Hong Kong : University of Hong Kong], 1991. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13068568.
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Lu, Hao. "Approximation and applications of distributed delay." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00961273.
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A distributed delay is a linear input-output operators and appears in many control problems. We investigate distributed delay and its applications. After introducing the definition and the main properties of the distributed delay, the numerical implementation problem of distributed delays is analyzed and a general method for its approximation is given. Then three applications are focused on where distributed delay appears. The first application is the stable inversion and model matching. A new class of stable inversion and model matching problem for finite dimensional linear time-invariant systems is defined. The stable inversion (resp. model matching) is an approximation of the inverse of a given model (resp. model matching), where exact inversion (resp. exact matching) is reached after a time $t=h$, which is a parameter of our procedure. The second application is concerned with stabilization and finite spectrum assignment for a class of infinite dimensional systems. The last application concerns observer synthesis for estimation or output control. For linear finite dimensional systems. A closed-loop memoryless observer by input injection is introduced. Asymptotic convergence as well as finite time convergence of the estimation are analyzed by output injection and input information via distributed delay. At last, we introduce a new class for approximation of distributed parameter systems. We work on the graph topology, and show that under some weak assumptions, such an approximation can be realized using distributed delay.
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Park, Young-Saeng. "Automatic schedule computation for distributed real-time systems using timed automata." Thesis, Northumbria University, 2008. http://nrl.northumbria.ac.uk/745/.
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The time-triggered architecture is becoming accepted as a means of implementing scalable, safer and more reliable solutions for distributed real-time systems. In such systems, the execution of distributed software components and the communication of messages between them take place in a fixed pattern and are scheduled in advance within a given scheduling round by a global scheduling policy. The principal obstacle in the design of time-triggered systems is the difficulty of finding the static schedule for all resources which satisfies constraints on the activities within the scheduling round, such as the meeting of deadlines. The scheduler has to consider not only the requirements on each processor but also the global requirements of system-wide behaviour including messages transmitted on networks. Finding an efficient way of building an appropriate global schedule for a given system is a major research challenge. This thesis proposes a novel approach to designing time-triggered schedules which is radically different from existing mathematical methods or algorithms for schedule generation. It entails the construction of timed automata to model the arrival and execution of software tasks and inter-task message communication for a system; the behaviour of an entire distributed system is thus a parallel composition of these timed automata models. A job comprises a sequence of tasks and messages; this expresses a system-wide transaction which may be distributed over a system of processors and networks. The job is formalized by a timed automata based on the principle that a task or message can be modelled by finite states and a clock variable. Temporal logic properties are formed to express constraints on the behaviour of the system components such as precedence relationships between tasks and messages and adherence to deadlines. Schedules are computed by formally verifying that these properties hold for an evolution of the system; a successful schedule is simply a trace generated by the verifier, in this case the UPPAAL model-checking tool has been employed to perform the behaviour verification. This approach guarantees to generate a practical schedule if one exists and will fail to construct any schedule if none exists. A prototype toolset has been developed to automate the proposed approach to create of timed automata models, undertake the analysis, extract schedules from traces and visualize the generated schedules. Two case studies, one of a cruise control system, the other a manufacturing cell system, are presented to demonstrate the applicability and usability of the approach and the application of the toolset. Finally, further constraints are considered in order to yield schedules with limited jitter, increased efficiency and system-wide properties.
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Panjaitan, Seno D. [Verfasser]. "Development Process for Distributed Automation Systems based on Elementary Mechatronic Functions / Seno D Panjaitan." Aachen : Shaker, 2008. http://d-nb.info/1164342428/34.
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Sahlholm, Per. "Distributed Road Grade Estimation for Heavy Duty Vehicles." Doctoral thesis, KTH, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32054.
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An increasing need for goods and passenger transportation drives continued worldwide growth in traffic. As traffic increases environmental concerns, traffic safety, and cost efficiency become ever more important. Advancements in microelectronics open the possibility to address these issues through new advanced driver assistance systems. Applications such as predictive cruise control, automated gearbox control, predictive front lighting control, and hybrid vehicle state-of-charge control decrease the energy consumption of vehicles and increase the safety. These control systems can benefit significantly from preview road grade information. This information is currently obtained using specialized survey vehicles, and is not widely available. This thesis proposes new methods to obtain road grade information using on-board sensors. The task of creating road grade maps is addressed by the proposal of a framework where vehicles using a road network collect the necessary data for estimating the road grade. The estimation can then be carried out locally in the vehicle, or in the presence of a communication link to the infrastructure, centrally. In either case the accuracy of the map increases over time, and costly road surveys can be avoided. This thesis presents a new distributed method for creating accurate road grade maps for vehicle control applications. Standard heavy duty vehicles in normal operation are used to collect measurements. Estimates from multiple passes along a road segment are merged to form a road grade map, which improves each time a vehicle retraces a route. The design and implementation of the road grade estimator are described, and the performance is experimentally evaluated using real vehicles. Three different grade estimation methods, based on different assumption on the road grade signal, are proposed and compared. They all use data from sensors that are standard equipment in heavy duty vehicles. Measurements of the vehicle speed and the engine torque are combined with observations of the road altitude from a GPS receiver, using vehicle and road models. The operation of the estimators is adjusted during gearshifts, braking, and poor satellite coverage, to account for variations in sensor and model reliability. The estimated error covariances of the road grade estimates are used together with their absolute positions to update a stored road grade map. Highway driving trials show that the proposed estimators produce accurate road grade data. The estimation performance improves as the number of road segment traces increases. A vehicle equipped with the proposed system will rapidly develop a road grade map for its area of operation. Simulations show that collaborative generation of the third dimension for a pre-existing large area two-dimensional map is feasible. The experimental results indicate that road grade estimates from the proposed methods are accurate enough to be used in predictive vehicle control systems to enhance safety, efficiency, and driver comfort in heavy duty vehicles. The grade estimators may also be used for on-line validation of road grade information from other sources. This is important in on-board applications, since the envisioned control applications can degrade vehicle performance if inaccurate data are used.<br>QC 20110408
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Celanovic, Ivan. "A Distributed Digital Control Architecture for Power Electronics Systems." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34998.
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This thesis proposes a novel approach to power electronics system design that is based on the open-architecture distributed digital controller and modular power electronics building blocks (PEBBs). The proposed distributed digital controller partitions the controller in three levels of control authority. The power stage controller, designated as hardware manager, is responsible for low-level hardware oriented tasks; the high level controller, designated as applications manager, performs higher-level application-oriented tasks; and the system level controller handles system control and monitoring functions.
Communications between the hardware-oriented controller and the higher-level controller are implemented with the previously proposed 125 Mbits/sec daisy-chained fiber optic communication protocol. Real-time control and status data are communicated by means of communication protocol. The distributed controller on the power converter level makes the system open, flexible and simple to use. Furthermore, this work gives an overview and comparison of current state-of-the-art communication protocols for real-time control applications with emphasis on industrial automation and motion control. All of the studied protocols have been considered as local area networks (LAN) for system-level control in power converter systems. The most promising solution has been chosen for the system level communication protocol.
This thesis also provides the details of design and implementation of the distributed controller. The design of both the hardware and software components are explained. A 100 kVA three-phase voltage source inverter (VSI) prototype was built and tested using the distributed controller approach to demonstrate the feasibility of the proposed concept.<br>Master of Science
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Maiolini, Jacopo. "On delay compensation control for systems with distributed input delay." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Questa tesi riguarda lo sviluppo di una nuova tecnica di controllo chiamata Delay Compensation per sistemi scalari che presentano un ritardo distribuito nei canali di ingresso. Lo scopo principale è di compensare realmente il lag intrinseco del sistema per un dato instante T_0. Esistono, infatti, alcune tecniche già utilizzate in questo ambito, chiamate predictor-like, che assegnano uno spettro stabile in closed-loop solamente dopo che il sistema è stato soggetto a tutto il ritardo presente in ingresso, non riuscendo perciò a compensarlo esattamente. L'obbiettivo secondario è dovuto a delle approssimazioni scaturite dall'implementazione in controllori real-time di questi controlli. Tutte le tecniche di cui sopra, inclusa Delay Compensation, necessitano infatti di un controllo anch'esso distribuito. Quando ci si scontra con la realtà, l'integrale di controllo deve essere approssimato tramite un integrazione numerica. Negli anni questa non idealità è stata ampiamente studiata, in particolar modo per il controllo Finite Spectrum Assignment (FSA) che verrà, nel caso di ritardi distribuiti di ingresso, relazionato con la tecnica Delay Compensation qui introdotta. Differenti metodi di quadratura verranno utilizzati e confrontati, per l'approssimazione dell'integrale di controllo, effettuando un analisi sia nel dominio del tempo sia nel dominio delle frequenze. Verrà poi effettuata un'estensione della tecnica nel caso di sistemi vettoriali, con dimostrazione annessa della validità nell'utilizzo del controllo Delay Compensation in questo frangente. Anche se non è presente una dimostrazione rigorosa dell'applicabilità del controllo Delay Compensation anche nel caso di un sistema Multi-Input, nella tesi sono presenti alcuni risultati considerando una semplificazione nel sistema controllato. La tesi si conclude elencando gli aspetti positivi e negativi derivanti dall'applicazione della tecnica Delay Compensation qui presentata e da un'indicazione di futuri sviluppi.
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Sairaman, Viswanath. "A Generalized Framework for Automatic Code Partitioning and Generation in Distributed Systems." Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1759.
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In distributed heterogeneous systems the partitioning of application software to be executed in a distributed fashion is a challenge by itself. The task of code partitioning for distributed processing involves partitioning the code into clusters and mapping those code clusters to the individual processing elements interconnected through a high speed network. Code generation is the process of converting the code partitions into individually executable code clusters and satisfying the code dependencies by adding communication primitives to send and receive data between dependent code clusters. In this work, we describe a generalized framework for automatic code partitioning and code generation for distributed heterogeneous systems. A model for system level design and synthesis using transaction level models has also been developed and is presented. The application programs along with the partition primitives are converted into independently executable concrete implementations. The process consists of two steps, first translating the primitives of the application program into equivalent code clusters, and then scheduling the implementations of these code clusters according to the inherent data dependencies. Further, the original source code needs to be reverse engineered in order to create a meta-data table describing the program elements and dependency trees. The data gathered, is used along with Parallel Virtual Machine (PVM) primitives for enabling the communication between the partitioned programs in the distributed environment. The framework consists of profiling tools, partitioning methodology, architectural exploration and cost analysis tools. The partitioning algorithm is based on clustering, in which the code clusters are created to minimize communication overhead represented as data transfers in task graph for the code. The proposed approach has been implemented and tested for different applications and compared with simulated annealing and tabu search based partitioning algorithms. The objective of partitioning is to minimize the communication overhead. While the proposed approach performs comparably with simulated annealing and better than tabu search based approaches in most cases in terms of communication overhead reduction, it is conclusively faster than simulated annealing and tabu search by an order of magnitude as indicated by simulation results. The proposed framework for system level design/synthesis provides an end to end rapid prototyping approach for aiding in architectural exploration and design optimization. The level of abstraction in the design phase can be fine tuned using transaction level models.
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Fabris, Marco. "Distributed Optimization Strategies for Mobile Multi-Agent Systems." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422819.
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In the recent years, the field of automation has witnessed a tendency to employ networked control for groups of agents to fulfill complex tasks arising from robotic surveillance to smart-grid production, from autonomous vehicle servicing to sensor network monitoring and a variety of space-based applications. Such mobile systems are referred to as multi-agent systems (MASs). In this thesis, the main research interest concerns how to design the effective decentralized coordination among autonomous agents, by means of a limited local sensing, to perform common tasks, aiming at reaching a high-quality overall performances. This approach has had a transformative impact in several application domains and, indeed, MASs possess well-known capabilities for autonomous and intelligent operation based on planning, reactivity, learning, proactivity, mobility, adaptivity and reasoning. Furthermore, such elements collaborate to seek a solution to problems that are out of reach for the single entity. What has led to this rapid progress in the last two decades is a combination of technological advances in price, scale of the platforms themselves, computational performance and a novel breakthrough of how the mobile robots should be arranged algorithmically. At the light of these increasing trends of investigation, it is crucial to reinforce the latest knowledge to keep up with the research demand.
The main objective of this thesis is firstly represented by the investigation of distributed strategies to optimize the design of MASs. In particular, numerous theoretical methodologies borrowed from Optimization Theory, Combinatorial Graph Theory, Dynamic Systems and Control are applied to realistic multi-agent-based models in order to offer new perspectives exploring efficient solutions and consolidate the vast paradigm of MASs.
To fully present the potential of the optimization approach applied to MASs, four major research studies are here considered and deeply examined in the theoretical, algorithmic and application point of view.
1. The development of a distributed algorithm to perform dynamic robotic coverage and focus on event with limited sensing capabilities.
2. The design of optimal control laws to accomplish time-invariant robotic formation tracking that also take into account energy consumption aspects.
3. The conceptualization, analysis and optimization of a general regularized distributed linear model to perform a state estimation from relative measurements.
4. The research of spectral properties connecting circulant algebraic entities to the Dirichlet kernel.<br>Recentemente, nel campo dell'automazione, si ha assistito a una tendenza data dell'impiego di controlli su reti formate da gruppi di agenti per realizzare complessi compiti, emergenti dalla sorveglianza robotica alla produzione di smart grids, dai servizi per veicoli autonomi al monitoraggio attuato grazie a reti di sensori e una vasta gamma di applicazioni spaziali. A tali sistemi mobili si fa riferimento con i cosiddetti sistemi multi-agente
(MASs). In questa tesi, il principale interesse di ricerca verte sull'indagine di un efficace coordinamento decentralizzato attraverso agenti autonomi, per mezzo di un utilizzo di sensori limitati a misurazioni locali, con lo scopo di svolgere compiti comuni, mirando al raggiungimento di prestazioni globali ad elevata qualità. Questo approccio ha avuto un impatto trasformativo in vari domini applicativi e, infatti, i MASs possiedono note capacità per operazioni intelligenti autonome basate sulla pianificazione, la reattività, l'apprendimento, la proattività, la mobilità, l'adattabilità e il ragionamento. Inoltre, tali elementi collaborano alla ricerca di soluzioni a problemi al di fuori della portata per la singola entità.
Ciò che ha condotto a questo rapido progresso negli ultimi due decenni è la combinazione di avanzamenti tecnologici nel prezzo, nelle dimensioni delle piattaforme stesse, nella capacità computazionale e in un'innovativa svolta sul come i robot mobili dovrebbero organizzarsi metodicamente. Alla luce di questo crescente andamento di investigazione, è cruciale rinforzare le conoscenze recenti per stare al passo con le esigenze di ricerca.
Il principale obiettivo di questa tesi è in primo luogo rappresentato dall'investigazione di strategie distribuite per ottimizzare la progettazione di MASs. In particolare, numerose metodologie teoriche prese in prestito dalla teoria dell'ottimizzazione, dalla teoria combinatoria dei grafi, dai sistemi dinamici e dal controllo sono applicate a realistici modelli multi-agente al fine di offrire nuove prospettive in grado di esplorare soluzioni efficienti e consolidare il vasto paradigma dei MASs. Allo scopo di presentare appieno il potenziale dell'approccio di ottimizzazione applicato ai MASs, quattro studi predominanti vengono qui considerati e largamente esaminati da un punto di vista teorico, algoritmico e applicativo.
1. Lo sviluppo di un algoritmo distribuito per eseguire copertura dinamica con agenti robotici e focalizzazione attorno a un evento mediante sensori a capacità limitata.
2. La progettazione di leggi ottimali per governare un gruppo di robot e realizzare un inseguimento tempo-invariante in formazione tenendo conto del consumo energetico.
3. Il concepimento, l'analisi e l'ottimizzazione di modelli lineari distribuiti e regolarizzati per portare a termine una stima dello stato a partire da misure relative.
4. La ricerca di proprietà spettrali che connettono entità algebriche dotate di struttura circolante al nucleo di Dirichlet.
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FRANCO, ELISA. "A STABILIZING DISTRIBUTED RECEDING HORIZON CONTROL SCHEME FOR COOPERATIVE LINEAR AND NONLINEAR SYSTEMS." Doctoral thesis, Università degli studi di Trieste, 2007. http://thesis2.sba.units.it/store/handle/item/12283.
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Neuner, Oliver. "Automatic learning of state machines for fault detection systems in discrete event based distributed systems." Thesis, KTH, Kommunikationsnät, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-53513.
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The electronic components in modern automobiles build up a distributed system with so called electronic control units connected via bus systems. As more safety- and security-relevant functions are implemented in such systems, the more important fault detection becomes. A promising approach to fault detection is to build a system model from state machines and compare its predictions with properties observed in a real system. In the automobile, potential are communication characteristics between the distributed control units. Especially, the sequence of transmitted messages can be used as the basis for supervising the communication. This thesis investigates if data gathered during system tests can be used to create state-machine system models. Such an automatically created model reflects the observed normal system behavior and can potentially be used for fault detection purposes. The task can be seen as learning a state machine from a single long message sequence. Today’s automata learning algorithms are not designed for such singlemessage- sequence input data. Especially, learning without interaction between the original system and the learning algorithm is in general a NPcomplete task. Additionally, if only positive data from the normal behaving system is available, the task is further complicated. The well-known Angluin’s L∗ state-machine learning algorithm works in general independent from the type of input data. In order for this algorithm to be applicable, certain queries have to be answered. This work proposes a statistical approach to answer such queries. The implemented adapted Angluin algorithm showed the potential of automatic model building in fault detection systems and, in particular, the possibility of learning state machines from a single positive data stream.
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Lena, Cota Guido. "Addressing selfishness in the design of cooperative systems." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI023/document.
Full textAbstract:
Les systèmes distribués collaboratifs, en particulier les systèmes pair-à-pair, forment l’infrastructure sous-jacente de nombreuses applications Internet, certaines parmi les plus populaires (ex : partage de fichiers, streaming multimédia). Ils se situent également à la base d’un ensemble de technologies émergentes telles que la blockchain et l’Internet des Objets. Le succès de ces systèmes repose sur la contribution volontaire, de la part des nœuds participants, aux ressources partagées (ex : bande passante réseau, puissance de calcul, stockage de données). Or ces nœuds sont des entités autonomes qui peuvent considérer comme plus avantageux de se comporter de manière égoïste, c’est-à-dire de refuser de collaborer. De tels comportements peuvent fortement impacter les performances et la stabilité opérationnelles du système cible. Prendre en compte et prévenir les comportements égoïstes des nœuds est donc essentiel pour garantir l’efficacité et la fiabilité des systèmes coopératifs. Cependant, cela exige du développeur, en dépit de la grande quantité de techniques et d’approches proposées dans la littérature, des connaissances multisectorielles approfondies. L'objectif de cette thèse est de concevoir et étudier de nouveaux outils théoriques et pratiques pour aider les concepteurs de systèmes distribués collaboratifs à faire face à des nœuds égoïstes. La première contribution, basée sur une analyse exhaustive de la littérature sur les comportements égoïstes dans les systèmes distribués, propose un modèle de classification pour identifier et analyser les comportements égoïstes les plus importants sur lesquels il est important de se concentrer lors de la conception d'un système coopératif. Dans la deuxième contribution, nous proposons RACOON, un framework pour la conception et la configuration de systèmes coopératifs résilients aux comportements égoïstes. Outre un ensemble de mécanismes d'incitation à la coopération, RACOON fournit une méthodologie semi-automatique d’intégration et de calibration de ces mécanismes de manière à garantir le niveau de performance souhaité. RACOON s’appuie sur une analyse du système cible fondée sur la théorie des jeux et sur des simulations pour prédire l’existence de nœuds égoïstes dans le système. RACOON a été étendu en un deuxième framework, RACOON++. Plus précis, plus flexible, RACOON++ offre également une plus grande facilité d'utilisation. Une dernière contribution, SEINE, propose un framework pour la modélisation et l'analyse des différents types de comportements égoïstes dans un système coopératif. Basé sur un langage dédié, développé pour décrire les scénarios de comportement égoïstes, SEINE fournit un support semi-automatique pour la mise en œuvre et l'étude de ces scénarios dans un simulateur choisi sur la base de l’état de l’art (PeerSim)<br>Cooperative distributed systems, particularly peer-to-peer systems, are the basis of several mainstream Internet applications (e.g., file-sharing, media streaming) and the key enablers of new and emerging technologies, including blockchain and the Internet of Things. Essential to the success of cooperative systems is that nodes are willing to cooperate with each other by sharing part of their resources, e.g., network bandwidth, CPU capability, storage space. However, as nodes are autonomous entities, they may be tempted to behave in a selfish manner by not contributing their fair share, potentially causing system performance degradation and instability. Addressing selfish nodes is, therefore, key to building efficient and reliable cooperative systems. Yet, it is a challenging task, as current techniques for analysing selfishness and designing effective countermeasures remain manual and time-consuming, requiring multi-domain expertise. In this thesis, we aim to provide practical and conceptual tools to help system designers in dealing with selfish nodes. First, based on a comprehensive survey of existing work on selfishness, we develop a classification framework to identify and understand the most important selfish behaviours to focus on when designing a cooperative system. Second, we propose RACOON, a unifying framework for the selfishness-aware design and configuration of cooperative systems. RACOON provides a semi-automatic methodology to integrate a given system with practical and finely tuned mechanisms to meet specified resilience and performance objectives, using game theory and simulations to predict the behaviour of the system when subjected to selfish nodes. An extension of the framework (RACOON++) is also proposed to improve the accuracy, flexibility, and usability of RACOON. Finally, we propose SEINE, a framework for fast modelling and evaluation of various types of selfish behaviour in a given cooperative system. SEINE relies on a domain-specific language for describing the selfishness scenario to evaluate and provides semi-automatic support for its implementation and study in a state-of-the-art simulator