Dissertations / Theses on the topic 'Distributed applications'

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1

Dixon, Eric Richard. "Developing distributed applications with distributed heterogenous databases." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/42748.

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2

Mir, Taheri Seyed Mohammad. "Distributed Crawling of Rich Internet Applications." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32089.

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Web crawlers visit internet applications, collect data, and learn about new web pages from visited pages. Web crawlers have a long and interesting history. Quick expansion of the web, and the complexity added to web applications have made the process of crawling a very challenging one. Different solutions have been proposed to reduce the time and cost of crawling. New generation of web applications, known as Rich Internet Applications (RIAs), pose major challenges to the web crawlers. RIAs shift a portion of the computation to the client side. Shifting a portion of the application to the client browser influences the web crawler in two ways: First, the one-to-one correlation between the URL and the state of the application, that exists in traditional web applications, is broken. Second, reaching a state of the application is no longer a simple operation of navigating to the target URL, but often means navigating to a seed URL and executing a chain of events from it. Due to these challenges, crawling a RIA can take a prohibitively long time. This thesis studies applying distributed computing and parallel processing principles to the field of RIA crawling to reduce the time. We propose different algorithms to concurrently crawl a RIA over several nodes. The proposed algorithms are used as a building block to construct a distributed crawler of RIAs. The different algorithms proposed represent different trade-offs between communication and computation. This thesis explores the effect of making different trade-offs and their effect on the time it takes to crawl RIAs. We study the cost of running a distributed RIA crawl with client-server architecture and compare it with a peer-to-peer architecture. We further study distribution of different crawling strategies, namely: Breath-First search, Depth-First search, Greedy algorithm, and Probabilistic algorithm. To measure the effect of different design decisions in practice, a prototype of each algorithm is implemented. The implemented prototypes are used to obtain empirical performance measurements and to refine the algorithms. The ultimate refined algorithm is used for experimentation with a wide range of applications under different circumstances. This thesis finally includes two theoretical studies of load balancing algorithms and distributed component-based crawling and sets the stage for future studies.
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Parkin, Simon Edward. "Monitoring middleware for distributed applications." Thesis, University of Newcastle Upon Tyne, 2007. http://hdl.handle.net/10443/2099.

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With growing maturity Internet services are proving integral to the provision of computer services. To provide consistent end-user experiences these services are increasingly augmented with some notion of 'Quality-of-Service' (QoS), which typically requires the management of computing resources to maintain a predictable level of service performance. It is difficult to guarantee consistent servIce provision In dynamic and open environments such as the Internet. However service monitoring can be used to inform compensatory actions by collecting meaningful service performance data from strategic points in an active service environment. Due to the unpredictable nature of the Internet distributed monitoring mechanisms face challenges with respect to the various communication protocols, application languages, and monitoring requirements associated with a service environment. With the growing popularity of Internet services creation of monitoring solutions on a per- service basis becomes time-consuming and misses opportunities to re-use existing logic. Ideally monitoring solutions would be domain-agnostic, automatically generated and automatically deployed. This thesis progresses these ambitions by providing a generic, distributed monitoring and evaluation framework based on Metric Collector (MeCo) components. These components can transparently gather measurement data across a range of service technologies as used within E-Commerce service environments. MeCo components form part of a framework which can interpret Service Level Agreements (SLAs) to automatically provide tailored service monitoring. The evaluation paradigms of the Meeo Framework are re-appropriated for use in Distributed Virtual Environments (DYEs). Quantifiable QoS requirements are established for Interest Management mechanisms (which limit message production based on object localities within a DYE). These are then incorporated into a DVE Simulator application. This application allows DYE application developers to evaluate Interest Management configurations for their suitability. Extensions to the DVE Simulator are exhibited in the Evolutionary Optimisation Simulator (EOS), which provides automated optimisation capabilities for DVE configurations through utilisation of genetic algorithm techniques.
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Nevelsteen, Kim J. L. "Distributed Technology-Sustained Pervasive Applications." Doctoral thesis, Stockholms universitet, Institutionen för data- och systemvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-129151.

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Technology-sustained pervasive games, contrary to technology-supported pervasive games, can be understood as computer games interfacing with the physical world. Pervasive games are known to make use of ‘non-standard input devices’ and with the rise of the Internet of Things (IoT), pervasive applications can be expected to move beyond games. This dissertation is requirements- and development-focused Design Science research for distributed technology-sustained pervasive applications, incorporating knowledge from the domains of Distributed Computing, Mixed Reality, Context-Aware Computing, Geographical Information Systems and IoT. Computer video games have existed for decades, with a reusable game engine to drive them. If pervasive games can be understood as computer games interfacing with the physical world, can computer game engines be used to stage pervasive games? Considering the use of non-standard input devices in pervasive games and the rise of IoT, how will this affect the architectures supporting the broader set of pervasive applications? The use of a game engine can be found in some existing pervasive game projects, but general research into how the domain of pervasive games overlaps with that of video games is lacking. When an engine is used, a discussion of, what type of engine is most suitable and what properties are being fulfilled by the engine, is often not part of the discourse. This dissertation uses multiple iterations of the method framework for Design Science for the design and development of three software system architectures. In the face of IoT, the problem of extending pervasive games into a fourth software architecture, accommodating a broader set of pervasive applications, is explicated. The requirements, for technology-sustained pervasive games, are verified through the design, development and demonstration of the three software system architectures. The scaling up of the architecture to support distributed pervasive applications, is based on research in the domain of Virtual Worlds and IoT. The results of this dissertation are: the aligning of the Pervasive Games research domain with that of Virtual Worlds, the mapping of virtual time and space to physical counterparts, the scaling up of pervasive games to distributed systems, and the explication of the problem of incorporating IoT into pervasive applications. The implication of this dissertation is to ensure that pervasive games are not left reinventing existing technologies.
Teknikförmedlade verklighetsspel (technology-sustained pervasive games), i motsats till teknikstödda verklighetsspel (technology-supported pervasive games), kan förstås som dataspelets gränssnitt mot den fysiska världen. Verklighetsspel games är kända för att använda sig av ‘icke-standardiserade inmatningsenheter’ och med ökningen av Sakernas Internet (Internet of Things) (IoT), kan verklighetsapplikationer (pervasive applications) förväntas gå längre än verklighetsspel. Denna avhandling omfattar krav- och utvecklingfokuserad (Design Science) forskning för distribuerad teknik omfattande verklighetsspel, som innehåller kunskap från områdena distribuerad databehandling (Distributed Computing), blandad realitet (Mixed Reality), kontextmedveten databehandling, geografiska informationssystem och IoT. Dataspel har funnits i decennier, ofta med en återanvändbar spelmotor för att driva dem. Om verklighetsspel kan förstås som dataspel med gränssnitt mot den fysiska världen, kan då dataspelsmotorer användas för att iscensätta verklighetsspel? Med tanke på användningen av ickestandardiserade inmatningsenheter i verklighetsspel och den tilltagande mängde IoT tillämpningar, hur kommer detta att påverka arkitekturen som stöder verklighetsspel? Användningen av en konventionell spelmotor kan återfinnas i vissa befintliga verklighetsspelsprojekt, men mer generell forskning om hur verklighetsspel överlappar med konventionella dataspel saknas. När en konventionell dataspelsmotor används, är en diskussion om vilken typ av motor som är mest lämplig och vilka egenskaper uppfylls av motorn ofta inte en del av diskursen. Denna avhandling använder flera iterationer av metodramverket för design vetenskap (method framework for Design Science) för konstruktion och utveckling av tre mjukvarusystemarkitekturer. Med tanke på IoT utarbetas problemet att utvidga verklighetsspel till en fjärde mjukvaruarkitektur som kan tillmötesgå en bredare uppsättning av verklighetsapplikationer. Kraven för teknikförmedlade verklighetsspel verifieras genom design, utveckling och demonstration av tre mjukvarusystemarkitekturer. Uppskalning av arkitekturen för att stödja distribuerade verklighetsspel är baserad på forskning inom området för virtuella världar och IoT. Resultaten från avhandlingen är: anpassning av forskningsområdet verklighetsspel med forskningsområdet virtuella världar, metod för matchning av virtuell tid och utrymme till fysiska motsvarigheter, uppskalning av verklighetsspel till distribuerade system, och utarbetning av problemen med att införliva IoT in verklighetsapplikationer. Innebörden av denna avhandling är att se till att implementeringen av verklighetsspel inte leder till att man återuppfinner redan existerande teknik.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Submitted. Paper 6: Submitted. Paper 7: Submitted.

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Morajko, Anna. "Dynamic Tuning of Parallel/Distributed Applications." Doctoral thesis, Universitat Autònoma de Barcelona, 2004. http://hdl.handle.net/10803/3043.

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Andersson, Filip, and Simon Norberg. "Scalable applications in a distributed environment." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3917.

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As the amount of simultaneous users of distributed systems increase, scalability is becoming an important factor to consider during software development. Without sufficient scalability, systems might have a hard time to manage high loads, and might not be able to support a high amount of users. We have determined how scalability can best be implemented, and what extra costs this leads to. Our research is based on both a literature review, where we have looked at what others in the field of computer engineering thinks about scalability, and by implementing a highly scalable system of our own. In the end we came up with a couple of general pointers which can help developers to determine if they should focus on scalable development, and what they should consider if they choose to do so.
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Kaushal, Seema. "Automating the instrumentation in distributed applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39838.pdf.

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8

Yeung, Kwok Cheung. "Dynamic performance optimisation of distributed applications." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405781.

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9

Wu, Maomao. "Adaptive privacy management for distributed applications." Thesis, Lancaster University, 2007. http://eprints.lancs.ac.uk/12984/.

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In networked computing environments, it becomes increasingly difficult for normal people to manage privacy, i.e., “to determine for themselves when, how, and to what extent information about them is communicated with others”. The thesis argues that achieving better privacy is not about hiding as much personal information as possible but enabling personal information disclosure at a level of openness that is as close as to a user’s desired level to assist him/her in accomplishing useful tasks. Following Palen and Dourish’s observation that privacy management is a dialectic and dynamic boundary regulation process [Palen03], the thesis argues that no set of pre-specified static privacy policies can meet users' changing requirements for privacy in networked computing environments, and therefore a new approach (i.e., adaptive privacy management) is proposed as the process that a user and/or a system to continuously adjust the system behaviour of disclosing personal information according to the user's changing desire for openness. In this thesis, we propose a set of requirements for adaptive privacy management and i the design and implementation of a middleware that meets these requirements for the target domain of applications that enable intentional sharing of personal information in networked computing environments. The middleware facilitates the creation of adaptive privacy aware applications that allows users or the system on behalf of the user to adjust the balance between openness and closedness; leading to an evolution of the users’ privacy preferences as a result of on-going interactions. A prototype adaptive privacy management system was implemented based on this middleware; demonstrating the feasibility of adaptive privacy management for the target domain. Both the principles of adaptive privacy management and the prototype implementation were evaluated based on the results of a detailed user study using a GSM location sharing application constructed using the prototype platform. The study reveals the our core requirements are important for end users, and that our supporting design did provide adequate support for the characteristics we propose.
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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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Bates, John. "Presentation support for distributed multimedia applications." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319546.

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Cheng, Winnie Wing-Yee. "Information flow for secure distributed applications." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/55095.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 171-177).
Private and confidential information is increasingly stored online and increasingly being exposed due to human errors as well as malicious attacks. Information leaks threaten confidentiality, lead to lawsuits, damage enterprise reputations, and cost billion of dollars. While distributed computing architectures provide data and service integration, they also create information flow control problems due to the interaction complexity among service providers. A main problem is the lack of an appropriate programming model to capture expected information flow behaviors in these large distributed software infrastructures. This research tackles this problem by proposing a programming methodology and enforcement platform for application developers to protect and share their sensitive data. We introduce Aeolus, a new platform intended to make it easier to build distributed applications that avoid the unauthorized release of information. The Aeolus security model is based on information flow control but differs from previous work in ways that we believe make it easier to use and understand. In addition, Aeolus provides a number of new mechanisms (anonymous closures, compound tags, boxes, and shared volatile state) to ease the job of writing applications. This thesis provides examples to show how Aeolus features support secure distributed applications. It describes the system design issues and solutions in designing a prototype implementation and presents performance results that show our platform has low overhead.
by Winnie Wing-Yee Cheng.
Ph.D.
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Brook, Matthew Jess. "Dynamic contention management for distributed applications." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2630.

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Distributed applications often make use of replicated state to afford a greater level of availability and throughput. This is achieved by allowing individual processes to progress without requiring prior synchronisation. This approach, termed optimistic replication, results in divergent replicas that must be reconciled to achieve an overall consistent state. Concurrent operations to shared objects in the replicas result in conflicting updates that require reconciliatory action to rectify. This typically takes the form of compensatory execution or simply undoing and rolling back client state. When considering user interaction with the application, there exists relationships and intent in the ordering and execution of these operations. The enactment of reconciliation that determines one action as conflicted may have far reaching implications with regards to the user’s original intent. In such scenarios, the compensatory action applied to a conflict may require previous operations to also be undone or compensated such that the user’s intent is maintained. Therefore, an ability to manage the contention to the shared data across the distributed application to pre-emptively lower conflicts resulting from these infringements is desirable. The aim is to not hinder throughput, achieved from the weaker consistency model known as eventual consistency. In this thesis, a model is presented for a contention management framework that schedules access using the expected execution inherent in the application domain to best inform the contention manager. A backoff scheme is employed to create an access schedule, preserving user intent for applications that require this high level of maintenance for user actions. By using such an approach, this results in a performance improvement seen in the reduction of the overall number of conflicts, while also improving overall system throughput. This thesis describes how the contention management scheme operates and, through experimentation, the performance benefits received.
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Campadello, Stefano. "Middleware infrastructure for distributed mobile applications." Helsinki : University of Helsinki, 2003. http://ethesis.helsinki.fi/julkaisut/mat/tieto/vk/campadello/.

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AGATE, Vincenzo. "REPUTATION MANAGEMENT ALGORITHMS IN DISTRIBUTED APPLICATIONS." Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/395198.

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Nowadays, several distributed systems and applications rely on interactions between unknown agents that cooperate in order to exchange resources and services. The distributed nature of these systems, and the consequent lack of a single centralized point of control, let agents to adopt selfish and malicious behaviors in order to maximize their own utility. To address such issue, many applications rely on Reputation Management Systems (RMSs) to estimate the future behavior of unknown agents before establishing actual interactions. The relevance of these systems is even greater if the malicious or selfish behavior exhibited by a few agents may reduce the utility perceived by cooperative agents, leading to a damage to the whole community. RMSs allow to estimate the expected outcome of a given interaction, thus providing relevant information that can be exploited to take decisions about the convenience of interacting with a certain agent. Agents and their behavior are constantly evolving and becoming even more complex, so it is increasingly difficult to successfully develop the RMS, able to resist the threats presented. A possible solution to this problem is the use of agent-based simulation software designed to support researchers in evaluating distributed reputation management systems since the design phase. This dissertation presents the design and the development of a distributed simulation platform based on HPC technologies called DRESS. This solution allows researchers to assess the performance of a generic reputation management system and provides a comprehensive assessment of its ability to withstand security attacks. In the scientific literature, a tool that allows the comparison of distinct RMS and different design choices through a set of defined metrics, also supporting large-scale simulations, is still missing. The effectiveness of the proposed approach is demonstrated by the application scenario of user energy sharing systems within smart-grids and by considering user preferences differently from other work. The platform has proved to be useful for the development of an energy sharing system among users, which with the aim of maximizing the amount of energy transferred has exploited the reputation of users once learned their preferences.
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Abid, Rim. "Coordination and reconfiguration of distributed cloud applications." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAM055/document.

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Les applications reparties dans le nuage sont constituées d'un ensemble de composants logiciels interconnectés et répartis sur plusieurs machines virtuelles. Cet environnement nécessite des protocoles pour configurer dynamiquement ces applications. Nous présentons dans la première partie de cette thèse un nouveau protocole pour résoudre les dépendances dans ces applications. Ce protocole consiste à (dé) connecter et démarrer/arrêter les composants dans un ordre spécifique. Il supporte les pannes des machines virtuelles et les opérations de reconfiguration se terminent toujours avec succès. Ces machines virtuelles interagissent à travers un «publish-subscribe communication media» et se reconfigurent d'une manière décentralisée. La conception de ces protocoles étant une source d'erreurs, nous avons étudié l'utilisation du langage formelle LNT pour spécifier le protocole et les outils disponibles dans la boîte à outils CADP pour le vérifier. D'autre part, la gestion des applications reparties dans le nuage est une tâche complexe car l'administration manuelle n'est plus réaliste pour ces systèmes. Nous avons proposé d'automatiser certaines fonctions d'administration en utilisant des boucles de contrôle appelées gestionnaires autonomes. Plusieurs gestionnaires peuvent être déployés pour la gestion de la même application. Cependant, leur utilisation sans coordination peut conduire à des incohérences et des situations d'erreur. Dans la deuxième partie de cette thèse, nous avons proposé une nouvelle approche pour coordonner plusieurs gestionnaires autonomes. Cette approche repose sur une langue de coordination simple, de nouvelles techniques asynchrone pour la synthèse de contrôleur et la génération de code Java. Nous avons appliqué notre approche pour coordonner les applications de cloud computing dans le monde réel
Cloud applications are composed of a set of interconnected software components distributed over several virtual machines. There is a need for protocols that can dynamically reconfigure such distributed applications. We present in the first part of this thesis a novel protocol, which can resolve dependencies in these applications, by (dis)connecting and starting/stopping components in a specific order. The protocol also supports virtual machine failures. The virtual machines interact through a publish-subscribe communication media and reconfigure themselves upon demand in a decentralised fashion. Designing such protocols is an error-prone task. Therefore, we investigated the use the LNT value-passing process algebra to specify the protocol and the model checking tools available in the CADP toolbox to verify it.Managing distributed cloud applications is a challenging problem because manual administration is no longer realistic for these complex distributed systems. Thus, autonomic computing is a promising solution for monitoring and updating these applications automatically. This is achieved through the automation of administration functions and the use of control loops called autonomic managers. Multiple autonomic managers can be deployed in the same system and must make consistent decisions. Using them without coordination may lead to inconsistencies and error-prone situations. In the second part of the thesis, we propose our approach for coordinating stateful autonomic managers, which relies on a simple coordination language, new techniques for asynchronous controller synthesis and Java code generation. We used our approach for coordinating real-world cloud applications
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Khan, Izhar Ahmed. "A Distributed Context Simulation Component." Thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-32576.

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Mobile devices with access to large numbers of sensors with internet access move forwards the development of intelligent applications towards new shape of ubiquitous applications. In order to create such applications we need to be able to do simulations to test and deploy. Current simulators do not permit this since they are centralized and the information is not shared globally. Therefore we cannot use them to test application built on distributed sensor information. I selected Siafu as the simulator component. In the next step, the simulator was customized according to the requirements of the project. There are different possibilities to achieve this task, but a simple GUI is made to control the simulator.The end result is a complete architecture for simulating context aware scenarios. The implementation is tested by running the simulator and dumping the context data into the PGRID overlay. For future work, implementing proximity estimation between the agents will be a good idea and can be interesting as well.
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Tejedor, Saavedra Enric. "Programming and parallelising applications for distributed infrastructures." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/129576.

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The last decade has witnessed unprecedented changes in parallel and distributed infrastructures. Due to the diminished gains in processor performance from increasing clock frequency, manufacturers have moved from uniprocessor architectures to multicores; as a result, clusters of computers have incorporated such new CPU designs. Furthermore, the ever-growing need of scienti c applications for computing and storage capabilities has motivated the appearance of grids: geographically-distributed, multi-domain infrastructures based on sharing of resources to accomplish large and complex tasks. More recently, clouds have emerged by combining virtualisation technologies, service-orientation and business models to deliver IT resources on demand over the Internet. The size and complexity of these new infrastructures poses a challenge for programmers to exploit them. On the one hand, some of the di culties are inherent to concurrent and distributed programming themselves, e.g. dealing with thread creation and synchronisation, messaging, data partitioning and transfer, etc. On the other hand, other issues are related to the singularities of each scenario, like the heterogeneity of Grid middleware and resources or the risk of vendor lock-in when writing an application for a particular Cloud provider. In the face of such a challenge, programming productivity - understood as a tradeo between programmability and performance - has become crucial for software developers. There is a strong need for high-productivity programming models and languages, which should provide simple means for writing parallel and distributed applications that can run on current infrastructures without sacri cing performance. In that sense, this thesis contributes with Java StarSs, a programming model and runtime system for developing and parallelising Java applications on distributed infrastructures. The model has two key features: first, the user programs in a fully-sequential standard-Java fashion - no parallel construct, API call or pragma must be included in the application code; second, it is completely infrastructure-unaware, i.e. programs do not contain any details about deployment or resource management, so that the same application can run in di erent infrastructures with no changes. The only requirement for the user is to select the application tasks, which are the model's unit of parallelism. Tasks can be either regular Java methods or web service operations, and they can handle any data type supported by the Java language, namely les, objects, arrays and primitives. For the sake of simplicity of the model, Java StarSs shifts the burden of parallelisation from the programmer to the runtime system. The runtime is responsible from modifying the original application to make it create asynchronous tasks and synchronise data accesses from the main program. Moreover, the implicit inter-task concurrency is automatically found as the application executes, thanks to a data dependency detection mechanism that integrates all the Java data types. This thesis provides a fairly comprehensive evaluation of Java StarSs on three di erent distributed scenarios: Grid, Cluster and Cloud. For each of them, a runtime system was designed and implemented to exploit their particular characteristics as well as to address their issues, while keeping the infrastructure unawareness of the programming model. The evaluation compares Java StarSs against state-of-the-art solutions, both in terms of programmability and performance, and demonstrates how the model can bring remarkable productivity to programmers of parallel distributed applications.
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Wohlstadter, Eric A. "Aspect-oriented development of distributed object applications /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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Thesis (Ph. D.)--University of California, Davis, 2005.
Degree granted in Computer Science. Dissertation completed in 2004; degree granted in 2005. Also available via the World Wide Web. (Restricted to UC campuses)
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Harel, Nissim. "Memory Optimizations for Distributed Stream-based Applications." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/13988.

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Distributed stream-based applications manage large quantities of data and exhibit unique production and consumption patterns that set them apart from general-purpose applications. This dissertation examines possible ways of creating more efficient memory management schemes. Specifically, it looks at the memory reclamation problem. It takes advantage of special traits of streaming applications to extend the definition of the garbage collection problem for those applications and include not only data items that are not reachable but also items that have no effect on the final outcome of the application. Streaming applications typically fully process only a portion of the data, and resources directed towards the remaining data items (i.e., those that dont affect the final outcome) can be viewed as wasted resources that should be minimized. Two complementary approaches are suggested: 1. Garbage Identification 2. Adaptive Resource Utilization Garbage Identification is concerned with an analysis of dynamic data dependencies to infer those items that the application is no longer going to access. Several garbage identification algorithms are examined. Each one of the algorithms uses a set of application properties (possibly distinct from one another) to reduce the memory consumption of the application. The performance of these garbage identification algorithms is compared to the performance of an ideal garbage collector, using a novel logging/post-mortem analyzer. The results indicate that the algorithms that achieve a low memory footprint (close to that of an ideal garbage collector) perform their garbage identification decisions locally; however, they base these decisions on best-effort global information obtained from other components of the distributed application. The Adaptive Resource Utilization (ARU) algorithm analyzes the dynamic relationships between the production and consumption of data items. It uses this information to infer the capacity of the system to process data items and adjusts data generation accordingly. The ARU algorithm makes local capacity decisions based on best-effort global information. This algorithm is found to be as effective as the most successful garbage identification algorithm in reducing the memory footprint of stream-based applications, thus confirming the observation that using best-effort global information to perform local decisions is fundamental in reducing memory consumption for stream-based applications.
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Beznosov, Konstantin. "Engineering access control for distributed enterprise applications." FIU Digital Commons, 2000. http://digitalcommons.fiu.edu/etd/1651.

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Access control (AC) is a necessary defense against a large variety of security attacks on the resources of distributed enterprise applications. However, to be effective, AC in some application domains has to be fine-grain, support the use of application-specific factors in authorization decisions, as well as consistently and reliably enforce organization-wide authorization policies across enterprise applications. Because the existing middleware technologies do not provide a complete solution, application developers resort to embedding AC functionality in application systems. This coupling of AC functionality with application logic causes significant problems including tremendously difficult, costly and error prone development, integration, and overall ownership of application software. The way AC for application systems is engineered needs to be changed. In this dissertation, we propose an architectural approach for engineering AC mechanisms to address the above problems. First, we develop a framework for implementing the role-based access control (RBAC) model using AC mechanisms provided by CORBA Security. For those application domains where the granularity of CORBA controls and the expressiveness of RBAC model suffice, our framework addresses the stated problem. In the second and main part of our approach, we propose an architecture for an authorization service, RAD, to address the problem of controlling access to distributed application resources, when the granularity and support for complex policies by middleware AC mechanisms are inadequate. Applying this architecture, we developed a CORBA-based application authorization service (CAAS). Using CAAS, we studied the main properties of the architecture and showed how they can be substantiated by employing CORBA and Java technologies. Our approach enables a wide-ranging solution for controlling the resources of distributed enterprise applications.
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Fuad, Mohammad Muztaba. "An autonomic software architecture for distributed applications." Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/fuad/FuadM0807.pdf.

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Simons, Christof. "Context aware applications in mobile distributed systems." Aachen Shaker, 2007. http://d-nb.info/987900757/04.

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Simons, Christof. "Context aware applications in mobile distributed systems /." Aachen : Shaker, 2008. http://d-nb.info/987900757/04.

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Thanitsukkarn, Thanwadee. "Multiperspective development environment for configurable distributed applications." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314226.

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Fergus, Edward Joseph. "Specifying distributed applications : the limits of formality." Thesis, Open University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236204.

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Wang, Wei. "Distributed real-time processing for automotive applications." Thesis, Cranfield University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427159.

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Chan, Patrick Wai-Ho. "A mobile system for distributed multimedia applications." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10866.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.
Includes bibliographical references (p. 127-129).
by Patrick Wai-Ho Chan.
M.Eng.
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Phillips, Brent M. (Brent Michael). "A distributed programming system for media applications." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36960.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.
Includes bibliographical references (leaves 104-106).
by Brent M. Phillips.
M.S.
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30

Branco, Miguel. "Distributed data management for large scale applications." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/72283/.

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Improvements in data storage and network technologies, the emergence of new highresolution scientific instruments, the widespread use of the Internet and the World Wide Web and even globalisation have contributed to the emergence of new large scale dataintensive applications. These applications require new systems that allow users to store, share and process data across computing centres around the world. Worldwide distributed data management is particularly important when there is a lot of data, more than can fit in a single computer or even in a single data centre. Designing systems to cope with the demanding requirements of these applications is the focus of the present work. This thesis presents four contributions. First, it introduces a set of design principles that can be used to create distributed data management systems for data-intensive applications. Second, it describes an architecture and implementation that follows the proposed design principles, and which results in a scalable, fault tolerant and secure system. Third, it presents the system evaluation, which occurred under real operational conditions using close to one hundred computing sites and with more than 14 petabytes of data. Fourth, it proposes novel algorithms to model the behaviour of file transfers on a wide-area network. This work also presents a detailed description of the problem of managing distributed data, ranging from the collection of requirements to the identification of the uncertainty that underlies a large distributed environment. This includes a critique of existing work and the identification of practical limits to the development of transfer algorithms on a shared distributed environment. The motivation for this work has been the ATLAS Experiment for the Large Hadron Collider (LHC) at CERN, where the author was responsible for the development of the data management middleware.
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Peterson, Krystal, Samuel Richter, Adam Schafer, Steve Grant, and Kurt Kosbar. "DISTRIBUTED COMPUTING PROCESSOR FOR SIGNAL PROCESSING APPLICATIONS." International Foundation for Telemetering, 2016. http://hdl.handle.net/10150/624191.

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Many signal processing, data analysis and graphical user interface algorithms are computationally intensive. This paper investigates a method of off-loading some of the calculations to remotely located processors. Inexpensive, commercial off the shelf processors are used to perform operations such as fast Fourier transforms and other numerically intensive algorithms. The data is passed to the processors, and results collected, using conventional network interfaces such as TCP/IP. This allows the processors to be located at any location, and also allows potentially large caches of processors to be shared between multiple applications.
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Scheidegger, Matthias. "Prediction of internet characteristics for distributed applications /." Bern : [s.n.], 2007. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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Burt, Robert. "Distributed Electrical Power System in Cubesat Applications." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1052.

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The single bus voltage distributed architecture is the mainstay architecture for small satellite spacecraft. Even large satellites follow this architecture. While they may have more than one voltage that is distributed, such as a high voltage bus and a low voltage bus, within a subsystem, there is usually one bus voltage. Each subsystem component is responsible for further regulation or point-of-load regulation. The Nano-satellite class, and more particularly the cubesat, have broken away from this norm and overwhelmingly implement a centralized architecture. With the advances of small, highly efficient monolithic dc-dc converters, this thesis researches the possibilities of implementing the distributed architecture at the cubesat scale. The Goal is to create a very efficient electrical power system design that has a high degree of utility, allowing it to be used for multiple missions, without having to redesign the system every time.
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Nair, Sreeja Sasidhara. "Designing safe and highly available distributed applications." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS272.

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La conception d'applications distribuées implique fondamentalement un compromis entre la sûreté et les performances. Nous nous concentrons sur les cas où la sûreté est la principale exigence. Dans le cadre des systèmes distribués basés sur l'état, nous proposons une méthodologie de preuve pour établir qu'une application donnée maintient un invariant donné. Notre approche permet de raisonner sur les opérations individuelles séparément. Nous démontrons que nos règles sont correctes et, à l'aide d'un moteur de preuve, nous illustrons leur utilisation par quelques exemples représentatifs. Pour les opérations conflictuelles, le développeur peut choisir entre la résolution de conflit ou la coordination. Nous présentons une nouvelle structure de données en forme d'arbre répliqué qui prend en charge les déplacements atomiques concurrents sans coordination et qui maintient l'invariant de l'arbre. Notre analyse identifie les cas où les déplacements concurrents sont intrinsèquement sûrs. Pour les autres cas, nous concevons un algorithme de résolution des conflits. La contrepartie est que dans certains cas, une opération de déplacement est "perdante". Étant donné la coordination requise par certaines applications pour la sûreté, elle peut être implémentée de nombreuses façons différentes. Même en se limitant aux verrous, ceux-ci peuvent utiliser diverses configurations qui diffèrent par: la granularité, le type et le placement. La performance de chaque configuration dépend de la charge de travail. Nous étudions le "treillis de coordination", l'espace de conception des configurations de verrouillage, et définissons un ensemble de mesures pour y naviguer systématiquement
Designing distributed applications involves a fundamental trade-off between safety and performance as described by CAP theorem. We focus on the cases where safety is the top requirement.For the subclass of state-based distributed systems, we propose a proof methodology for establishing that a given application maintains a given invariant. Our approach allows reasoning about individual operations separately. We demonstrate that our rules are sound, and with a mechanized proof engine, we illustrate their use with some representative examples. For conflicting operations, the developer can choose between conflict resolution or coordination. We present a novel replicated tree data structure that supports coordination-free concurrent atomic moves, and arguably maintains the tree invariant. Our analysis identifies cases where concurrent moves are inherently safe. For the remaining cases we devise a conflict resolution algorithm. The trade-off is that in some cases a move operation "loses". Given the coordination required by some application for safety, it can be implemented in many different ways. Even restricting to locks, they can use various configurations, differing by lock granularity, type, and placement. The performance of each configuration depends on workload. We study the "coordination lattice", i.e., design space of lock configurations, and define a set of metrics to systematically navigate them
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Toor, Salman Zubair. "Managing Applications and Data in Distributed Computing Infrastructures." Doctoral thesis, Uppsala universitet, Avdelningen för beräkningsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-173467.

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During the last decades the demand for large-scale computational and storage resources in science has increased dramatically. New computational infrastructures enable scientists to enter a new mode of science, e-science, which complements traditional theory and experiments. E-science is inherently interdisciplinary, involving researchers from several disciplines, and also opens up for large-scale collaborative efforts where physically distributed groups of scientists share software tools and data to make scientific progress. Within the field of e-science, new challenges are emerging in managing large-scale distributed computing efforts and distributed data sets. Different models, e.g. grids and clouds, have been introduced over the years, but new solutions built on these models are needed to enable easy and flexible use of distributed computing infrastructures by application scientists. In the first part of the thesis, application execution environments are studied. The goal is to hide technical details of the underlying distributed computing infrastructure and expose secure and user-friendly environments to the end users. First, a general-purpose solution using portal technology is described, enabling transparent and easy usage of a variety of grid systems. Then a problem-solving environment for genetic analysis is presented. Here the statistical software R is used as a workflow engine, enhanced with grid-enabled routines for performing the computationally demanding parts of the analysis. Finally, the issue of resource allocation in grid system is briefly studied and certain modifications in the distributed resource-brokering model for the ARC middleware are proposed. The second part of the thesis presents solutions for managing and analyzing scientific data using distributed storage resources. First, a new reliable and secure file-oriented distributed storage system, Chelonia, is presented. The architectural design of the system is described and implementation issues are considered. Also, the stability and scalable performance of Chelonia is verified using several test scenarios. Then, tools for providing an efficient and easy-to-use platform for data analysis built on Chelonia are presented. Here, a database driven approach is explored. An extended architecture where Chelonia is combined with the Web-Service MEDiator (WSMED) system is implemented, providing web service tools to query data without any further programming. This approach is then developed further and Chelonia is combined with SciSPARQL, a query language that extends SPARQL to queries over numeric scientific data. This results in a system that is capable of interactive analysis of distributed data sets. Writing customized modules in Java, Python or C can fulfill advanced application-specific analysis requirements. The viability of the approach is demonstrated by applying the system to data produced by URDME, a computational environment in systems biology and results for sample queries expressed in SciSPARQL are presented. Finally, the use of an open source storage cloud, Openstack – SWIFT, for analysis of data from CERN experiments is considered. Here, a pilot implementation for the ROOT data analysis framework is presented together with a performance evaluation.
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Deng, Jie. "Profiling large-scale live video streaming and distributed applications." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/43948.

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Today, distributed applications run at data centre and Internet scales, from intensive data analysis, such as MapReduce; to the dynamic demands of a worldwide audience, such as YouTube. The network is essential to these applications at both scales. To provide adequate support, we must understand the full requirements of the applications, which are revealed by the workloads. In this thesis, we study distributed system applications at different scales to enrich this understanding. Large-scale Internet applications have been studied for years, such as social networking service (SNS), video on demand (VoD), and content delivery networks (CDN). An emerging type of video broadcasting on the Internet featuring crowdsourced live video streaming has garnered attention allowing platforms such as Twitch to attract over 1 million concurrent users globally. To better understand Twitch, we collected real-time popularity data combined with metadata about the contents and found the broadcasters rather than the content drives its popularity. Unlike YouTube and Netflix where content can be cached, video streaming on Twitch is generated instantly and needs to be delivered to users immediately to enable real-time interaction. Thus, we performed a large-scale measurement of Twitchs content location revealing the global footprint of its infrastructure as well as discovering the dynamic stream hosting and client redirection strategies that helped Twitch serve millions of users at scale. We next consider applications that run inside the data centre. Distributed computing applications heavily rely on the network due to data transmission needs and the scheduling of resources and tasks. One successful application, called Hadoop, has been widely deployed for Big Data processing. However, little work has been devoted to understanding its network. We found the Hadoop behaviour is limited by hardware resources and processing jobs presented. Thus, after characterising the Hadoop traffic on our testbed with a set of benchmark jobs, we built a simulator to reproduce Hadoops job traffic With the simulator, users can investigate the connections between Hadoop traffic and network performance without additional hardware cost. Different network components can be added to investigate the performance, such as network topologies, queue policies, and transport layer protocols. In this thesis, we extended the knowledge of networking by investigated two widelyused applications in the data centre and at Internet scale. We (i) studied the most popular live video streaming platform Twitch as a new type of Internet-scale distributed application revealing that broadcaster factors drive the popularity of such platform, and we (ii) discovered the footprint of Twitch streaming infrastructure and the dynamic stream hosting and client redirection strategies to provide an in-depth example of video streaming delivery occurring at the Internet scale, also we (iii) investigated the traffic generated by a distributed application by characterising the traffic of Hadoop under various parameters, (iv) with such knowledge, we built a simulation tool so users can efficiently investigate the performance of different network components under distributed application.
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37

Wheater, Stuart Mark. "Constructing reliable distributed applications using actions and objects." Thesis, University of Newcastle Upon Tyne, 1989. http://hdl.handle.net/10443/1767.

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A computation model for distributed systems which has found widespread acceptance is that of atomic actions (atomic transactions) controlling operations on persistent objects. Much current research work is oriented towards the design and implementation of distributed systems supporting such an object and action model. However, little work has been done to investigate the suitability of such a model for building reliable distributed systems. Atomic actions have many properties which are desirable when constructing reliable distributed applications, but these same properties can also prove to be obstructive. This thesis examines the suitability of atomic actions for building reliable distributed applications. Several new structuring techniques are proposed providing more flexibility than hitherto possible for building a large class of applications. The proposed new structuring techniques are: Serialising Actions, Top-Level Independent Actions, N-Level Independent Actions, Common Actions and Glued Actions. A new generic form of action is also proposed, the Coloured Actions, which provides more control over concurrency and recovery than traditional actions. It will be shown that Coloured Actions provide a uniform mechanism for implementing most of the new structuring techniques, and at the same time are no harder to implement than normal actions. Thus this proposal is of practical importance. The suitability of new structuring techniques will be demonstrated by considering a number of applications. It will be shown that the proposed techniques provide natural tools for composing distributed applications.
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Zou, Li. "A New Architecture for Developing Component-based Distributed Applications." University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin974951548.

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39

Du, Wei. "Advanced middleware support for distributed data-intensive applications." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1126208308.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xix, 183 p.; also includes graphics (some col.). Includes bibliographical references (p. 170-183). Available online via OhioLINK's ETD Center
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Dai, Min. "Control of power converters for distributed generation applications." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1124329850.

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41

Madelaine, Eric. "Specification, Model Generation, and Verification of Distributed Applications." Habilitation à diriger des recherches, Université de Nice Sophia-Antipolis, 2011. http://tel.archives-ouvertes.fr/tel-00625248.

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Depuis 2001 j'ai développé au sein de l'équipe Oasis des travaux de recherche sur la sémantique des applications à base d'objets distribués, appliquant dans le contexte d'un vrai langage, et d'applications de taille réelle, mes recherches précédentes dans le domaine des algèbres de processus. Les différents aspects de ce travail touchent naturellement à la sémantique comportementale, et à la définition de procédures de génération de modèles prenant en compte les différentes facettes de la programmation d'applications distribuées, mais aussi, en amont, à l'analyse statique de code et aux techniques d'abstraction de modèles, et en aval aux outils de vérification de propriétés comportementales. Je montre dans ce mémoire la complexité de ces recherches et la grande variété des techniques requises. Nous avons mis en place une méthode cohérente basée sur un modèle sémantique très flexible, le modèle pNets (parameterized Networks of automata), qui nous offre un bon compromis entre décidabilité, complexité, et utilisabilité. Cette approche nous a permis de définir une sémantique comportementale pour différents aspects des applications à base d'objets ou de composants distribués, mais aussi une notion d'abstraction vers des modèles abstraits finis, permettant d'utiliser des outils de vérification de type " model-checking ". L'ensemble de ces aspects a donné lieu à la réalisation de prototypes, dans la plateforme VerCors, et à des cas d'étude de grande taille.
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Read, Tom Oliver Trevett. "Applications of distributed temperature sensing in subsurface hydrology." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/59401/.

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In the study of dynamic subsurface processes there is a need to monitor temperature and groundwater fluxes efficiently in both time and space. Distributed Temperature Sensing has recently become more accessible to researchers in Earth Sciences, and allows temperatures to be measured simultaneously, at small intervals, and over large distances along fibre optic cables. The capability of DTS in conjunction with heat injection to detect groundwater fluxes, is assessed in this thesis using a combination of numerical modelling, laboratory tests, and field trials at the Ploemeur research site in Brittany, France. In particular, three methodological approaches are developed: thermal dilution tests, point heating, and the hybrid cable method. A numerical model was developed to assess the sensitivity range of thermal dilution tests to groundwater flow. Thermal dilution tests undertaken at Ploemeur showed lithological contrasts, and allowed the apparent thermal conductivity to be estimated in-situ, but failed to detect previously identified transmissive fractures. The use of DTS to monitor in-well vertical flow is then investigated. This is first using a simple experiment deploying point heating (T-POT), which tracks a parcel of heated water vertically through the borehole. The method allowed for the relatively quick estimation of velocities in the well. The use of heated fibre optics is then trialled, and through a field test was shown to be sensitive to in-well vertical flow. However, the data suffered from a number of artefacts related to the cable installation. To address this, a hybrid cable system was deployed in a flume to determine the sensitivity relationship with flow angle and electrical power input. Additionally, a numerical model was developed, which suggested a lower limit for velocity estimation due to thermal buoyancy. With the emergence of Distributed Acoustic Sensing, fibre optics may become an increasingly practicable and complete solution for monitoring subsurface processes.
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Yang, Yongsheng. "Comparative study and implementation methodologies for distributed applications." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/27089.

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Today's rapid development of Internet demands highly concurrent and distributed systems. In this context, it is interesting to note that correct protocol specifications can be derived from a given service specification of the application. The main objective of this thesis is to introduce protocol derivation and develop general methodologies for designing distributed systems. Protocol synthesis focuses on generating an error-free protocol specification automatically from a higher-level service specification and it is a very important step in the protocol development process. Petri net is a very powerful model for describing and analyzing distributed, concurrent and asynchronous systems; therefore, we use it in protocol synthesis. Furthermore, we review SOAP (Simple Object Access Protocol), Java RMI (Remote Method Invocation) and J2EE (Java 2 Platform, Enterprise Edition) technologies and discuss their usages in decentralized, distributed applications. This thesis gives an overview of protocol engineering background knowledge, presents several protocol synthesis methods using Petri nets, gives general methodologies of distributed system implementation and presents a distribution prototype: An example service specification is used to derive a corresponding abstract protocol specification, which is implemented with three different approaches: SOAP, Java RMI and J2EE. Finally, the performance of these different implementation approaches is compared.
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44

Toor, Salman. "Managing applications and data in distributed computing infrastructures." Licentiate thesis, Uppsala universitet, Avdelningen för teknisk databehandling, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-121099.

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Over the last few decades, the needs of computational power and data storage by collaborative, distributed scientific communities have increased very rapidly. Distributed computing infrastructures such as computing and storage grids provide means to connect geographically distributed resources and helps in addressing the needs of these communities. Much progress has been made in developing and operating grids, but several issues still need further attention. This thesis discusses three different aspects of managing large-scale scientific applications in grids: • Using large-scale scientific applications is often in itself a complex task, and to set them up and run experiments in a distributed environment adds another level of complexity. It is important to design general purpose and application specific frameworks that enhance the overall productivity for the scientists. The thesis present further development of a general purpose framework where existing portal technology is combined with tools for robust and middleware independent job management. Also, a pilot implementation of a domain-specific problem solving environment based on a grid-enabled R solution is presented. • Many current and future applications will need large-scale storage systems. Centralized systems are eventually not scalable enough to handle huge data volumes and also have can have additional problems with security and availability. An alternative is a reliable and efficient distributed storage system. In the thesis the architecture of a self-healing, grid-aware distributed storage cloud, Chelonia, is described and performance results for a pilot implementation are presented. • In a distributed computing infrastructure it is very important to manage and utilize the available resources efficiently. The thesis presents a review of different resource brokering techniques and how they are implemented in different production level middlewares. Also, a modified resource allocation model for the Advanced Resource Connector (ARC) middleware is described and performance experiments are presented.
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45

Versteegh, Ronald. "Support for development of distributed systems management applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0021/MQ28679.pdf.

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46

Wang, Silong. "Object-oriented design for distributed real-time applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39704.pdf.

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Sheikh, Fahim A. "Sensitivity analysis of performance predictions for distributed applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/MQ27026.pdf.

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48

Nam, Beomseok. "Distributed multidimensional indexing for scientific data analysis applications." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/6795.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.
Thesis research directed by: Computer Science. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Venugopal, Srikumar. "Scheduling distributed data-intensive applications on global grids /." Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/0002929.

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Sampigethaya, Radhakrishna. "On the privacy of emerging distributed network applications /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6073.

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