Dissertations / Theses on the topic 'Session and event systems'
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Редько, Владислав Ігорович. "Система збору аналітики додатку для розробників ігор." Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/43959.
Full textAnalytics is a tool for developing and properly maintaining software products. Analytics systems are relevant for all post – release stages of game development-from collecting analytics to determining player engagement in the initial stages, to collecting analytics to develop updates. The aim of the work is to analyze existing analytics systems, and based on the research, develop an analytics system that would easily integrate into any game developed using C#, and display data in a convenient form for the developer. The note contains 64 pages, 29 Figures, 4 attachments and 14 links.
Аналитика - инструмент для разработки и правильного поддержания программных продуктов. Системы аналитики актуальны для всех пост-релизных этапах разработки игры - от сбора аналитики для определения вовлеченности игроков на начальных этапах, к сбору аналитики для разработки обновлений. Цель работы - проанализировать существующие системы Аналитки, и на основе исследования разработать систему аналитики, которая легко интегрировалась в любую игру, разработанную с помощью C #, и отражала данные в удобном для разработчика виде. Записка содержит 64 страницы, 29 рисунков, 4 приложения и 14 ссылок.
Wulff, Tobias. "Evaluation of and Mitigation against Malicious Traffic in SIP-based VoIP Applications in a Broadband Internet Environment." Thesis, University of Canterbury. Computer Science and Software Engineering, 2010. http://hdl.handle.net/10092/5120.
Full textCoen, Stephanie. "NEXUS Poster Session & Book Launch 2009 - Event Flyer." NEXUS, 2009. http://hdl.handle.net/2429/15386.
Full textAiken, Milam Worth. "An expert systems approach to group decision support systems pre-session planning." Diss., The University of Arizona, 1991. http://catalog.hathitrust.org/api/volumes/oclc/31253019.html.
Full textSchulz, Joseph Edward. "A desision support system for session scheduling." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/25106.
Full textNeykova, Rumyana. "Multiparty session types for dynamic verification of distributed systems." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/45276.
Full textFiege, Ludger. "Visibility in event based systems." Phd thesis, [S.l. : s.n.], 2005. http://elib.tu-darmstadt.de/diss/000574.
Full textVan, der Westhuizen Eugene Daniel. "A session layer for the X.400 message handling system." Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/18228.
Full textThe CCITT X.400 Message Handling System resides in the Application Layer of the seven-layer Reference Model for Open Systems Interconnection. It bypasses the services of the Presentation Layer completely to interact directly with the Session Layer. The objectives of this thesis are to show how the general Session Layer may be tailored to be minimally conformant to the requirements of X. 400; to produce a formal specification of this session layer; and to show how this session layer may be implemented on a real system. The session services required by X. 400 are those of the Halfduplex, Minor Synchronization, Exceptions and Activity Management functional units of the CCITT X.215 Session Service Definition. These services, and particularly their use by X.400, are described in detail. State tables describing these services are derived from the general session service state tables. Those elements of the CCITT X. 225 Session Protocol Specification which are required to provide only those services required by X. 400 are described in detail. State tables describing this session protocol are derived from the general session protocol state tables. A formal specification of the session layer for X.400 is presented using the Formal Description Technique Estelle. This specification includes a complete session entity, which characterizes the entire session layer for X.400. A session entity for supporting X.400 is partially implemented and interfaced to an existing X.400 product on a real system. Only the Session Connection Establishment Phase of the session protocol is implemented to illustrate the technique whereby the entire session protocol may be implemented. This implementation uses the C programming language in the UNIX operating system environment.
Chen, Tsu-Chun. "Theories for Session-based Governance for Large-scale Distributed Systems." Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8778.
Full textSeyboth, Georg Sebastian. "Event-based Controlfor Multi-Agent Systems." Thesis, KTH, Reglerteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105117.
Full textZhang, Xueqin. "Control of Boolean discrete event systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28860.pdf.
Full textCarlson, Jan. "Event Pattern Detection for Embedded Systems." Doctoral thesis, Västerås : Department of Computer Science and Electronics, Mälardalen University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-231.
Full textDesai, Sasi Bharath. "Discrete Event Simulation of Elevator Systems." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cmc_theses/343.
Full textStoddart, Bill. "The event based modelling of systems." Thesis, Teesside University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411174.
Full textHuang, Jing. "Directed control of discrete event systems." [Ames, Iowa : Iowa State University], 2009. 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:3369844.
Full textGuo, Ce. "Reconfigurable predictive systems for event streams." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/50159.
Full textLi, Chunhui. "Performance management of event processing systems." Thesis, Aston University, 2014. http://publications.aston.ac.uk/25175/.
Full textPonce, de León Hernan. "Testing concurrent systems through event structures." Thesis, Cachan, Ecole normale supérieure, 2014. http://www.theses.fr/2014DENS0035/document.
Full textComplex systems are everywhere and are part of our daily life. As a consequence, their failures can range from being inconvenient to being life-threatening. Testing is one of the most widely accepted techniques (especially in industry) to detect errors in a system. When the requirements of the system are described by a formal specification, conformance testing is used to guarantee a certain degree of confidence in the correctness of an implementation- in this setting a conformance relation formalizes the notion of correctness. This thesis focuses on conformance testing for concurrent systems. Conformance testing for concurrent system has mainly focused on models that interpret concurrency by interleavings. This approach does not only suf- fer from the state space explosion problem, but also lacks the ability to test properties of the specification such as independence between actions. For such reasons, we focus not only on partial order semantics for concurrency, but also propose a new semantics that allows to interleave some actions while forcing others to be implemented as independent. We propose a generalization of the ioco conformance relation, based on Petri nets specifications and their partial order semantics given by their unfoldings, preserving thus independence of actions from the specification. A complete testing framework for this conformance relation is presented. We introduce the notion of global test cases which handle concurrency, reducing not only the size of the test case, but also the number of tests in the test suite. We show how global test cases can be constructed from the unfolding of the specification based on a SAT encoding and we reduce the test selection problem to select a finite prefix of such unfolding: different testing criteria are defined based on the notion of cut-off events. Finally, we show that assuming each process of a distributed system has a local clock, global conformance can be tested in a distributed testing architecture using only local testers without any communication
Su, Rong. "Decentralized fault diagnosis for discrete-event systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0024/MQ50393.pdf.
Full textWang, Yuwei. "Supervisory control of Boolean discrete-event systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/MQ53446.pdf.
Full textHu, Tun. "Communication states in decentralized discrete-event systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ65626.pdf.
Full textBherer, Hans. "Controller Synthesis for Parameterized Discrete Event Systems." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/26696/26696.pdf.
Full textDiscrete event systems are a special type of dynamic systems. The state of these systems changes only at discrete instants of time and the term event is used to represent the occurrence of discontinuous changes. These systems are mostly man-made and arise in the domains of manufacturing systems, traffic systems, database management systems and communication protocols. This thesis investigates the control of parameterized discrete event systems when specifications are given in terms of predicates and satisfy a similarity assumption. For systems consisting of similar processes under total or partial observation, conditions are given to deduce properties of a system of n processes from properties of a system of n0 processes, with n ≥ n0. Furthermore, it is shown how to infer a control policy for the former from the latter’s, while taking into account interconnections between processes. This study is motivated by a weakness in current synthesis methods that do not scale well to huge systems.
Birkholz, Simon. "Determinism and predictability in extreme event systems." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17495.
Full textIn the last decades, extreme events, i.e., high-magnitude phenomena that cannot be described within the realm of Gaussian probability distributions have been observed in a multitude of physical systems. While statistical methods allow for a reliable identification of extreme event systems, the underlying mechanism behind extreme events is not understood. Extreme events are not well understood due to their rare occurrence and their onset under conditions that are difficult to reproduce. Thus, it is desirable to identify extreme event scenarios that can serve as a test bed. Optical systems exhibiting extreme events have been discovered to be ideal for such tests, and it is now desired to find more different examples to improve the understanding of extreme events. In this thesis, multifilamentation formed by femtosecond laser pulses is analyzed. Observation of the spatio-temporal dynamics of multifilamentation shows a heavy-tailed fluence probability distribution. This finding implies the onset of extreme events during multifilamentation. Linear analysis gives hints on the processes that drive the formation of extreme events. The multifilaments are also analyzed by nonlinear time series analysis, which provides information on determinism and chaos in the system. The analysis of the multifilament s is compared to an analysis of extreme event time series from ocean wave measurements and the supercontinuum output of an optical fiber. The analysis performed in this work shows fundamental differences in the extreme event mechnaism. While the extreme events in the optical fiber system are ruled by the stochastic changes of amplified quantum noise, in the multifilament and the ocean system extreme events appear as a result of the classical mechanical process of turbulence. This implies the predictability of extreme events. In this work, the predictability of extreme events is proven to be possible in a brief time window before the onset of the extreme event.
Zeldovich, Nickolai 1981. "Concurrency control for multiprocessor event-driven systems." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87303.
Full textIncludes bibliographical references (p. 41-43).
by Nickolai Zeldovich.
M.Eng.
Muthiah, Sathappan. "Design and Maintenance of Event Forecasting Systems." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/102866.
Full textDoctor of Philosophy
Event forecasting systems help reduce violence, loss/damage to humans and property. They find applicability in supply chain management, prioritizing citizen grievances, designing mea- sures to control violence and minimize disruptions and also in applications like health/tourism by providing timely travel alerts. Several issues exist with the design and maintenance of such event forecasting systems in general. Predictions from such systems may drift away from ground reality over time if not adapted to various shifts (or changes) in event occurrence patterns in real-time. A continuous source of ground-truth events is of paramount necessity for the continuous maintenance of forecasting systems. However ground-truth events used for training may not be reliable but often information about their uncertainty is not reflected in the systems that are used to build the ground truth. This dissertation focuses on addressing such issues pertaining to design and maintenance of event forecasting systems. We propose a framework for online drift-adaptation and also build machine learning methods capable of modeling and capturing uncertainty in event detection systems. Finally we propose and built a hybrid event coding system that can capture the best of both automated and manual event coders. We breakdown the overall event coding pipeline into several micro-tasks and propose individual methods for each micro-task. Each method is built with the capability to know what it doesn't know and thus is capable of balancing quality vs throughput based on available human resources.
Thiele, Johannes C. "Deep learning in event-based neuromorphic systems." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS403/document.
Full textInference and training in deep neural networks require large amounts of computation, which in many cases prevents the integration of deep networks in resource constrained environments. Event-based spiking neural networks represent an alternative to standard artificial neural networks that holds the promise of being capable of more energy efficient processing. However, training spiking neural networks to achieve high inference performance is still challenging, in particular when learning is also required to be compatible with neuromorphic constraints. This thesis studies training algorithms and information encoding in such deep networks of spiking neurons. Starting from a biologically inspired learning rule, we analyze which properties of learning rules are necessary in deep spiking neural networks to enable embedded learning in a continuous learning scenario. We show that a time scale invariant learning rule based on spike-timing dependent plasticity is able to perform hierarchical feature extraction and classification of simple objects of the MNIST and N-MNIST dataset. To overcome certain limitations of this approach we design a novel framework for spike-based learning, SpikeGrad, which represents a fully event-based implementation of the gradient backpropagation algorithm. We show how this algorithm can be used to train a spiking network that performs inference of relations between numbers and MNIST images. Additionally, we demonstrate that the framework is able to train large-scale convolutional spiking networks to competitive recognition rates on the MNIST and CIFAR10 datasets. In addition to being an effective and precise learning mechanism, SpikeGrad allows the description of the response of the spiking neural network in terms of a standard artificial neural network, which allows a faster simulation of spiking neural network training. Our work therefore introduces several powerful training concepts for on-chip learning in neuromorphic devices, that could help to scale spiking neural networks to real-world problems
Nobliá, Matilda, and Christian Ryan. "Contamination Event Detection in Water Distribution Systems." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214698.
Full textCaulkins, Bruce. "SESSION-BASED INTRUSION DETECTION SYSTEM TO MAP ANOMALOUS NETWORK TRAFFIC." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3466.
Full textPh.D.
Other
Arts and Sciences
Modeling and Simulation
Lindberg, Therese. "Discrete Event Simulation of Bus Terminals." Licentiate thesis, Linköpings universitet, Kommunikations- och transportsystem, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156646.
Full textBrito, Andrey. "Speculation in Parallel and Distributed Event Processing Systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-38911.
Full textSvensson, Harari Natalia. "Manufacturing systems model interoperability in discrete event simulation." Thesis, KTH, Industriell produktion, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91591.
Full textHashtrudi, Zad Shahin. "Fault diagnosis in discrete-event and hybrid systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0019/NQ45687.pdf.
Full textEstrada, Vargas Ana Paula, and Vargas Ana Paula Estrada. "Black-Box identification of automated discrete event systems." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2013. http://tel.archives-ouvertes.fr/tel-00846194.
Full textClark, Kenneth A. "Modeling single-event transients in complex digital systems." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FClark%5FKenneth%5Fphd.pdf.
Full textWen, Qin. "Fault-tolerant supervisory control of discrete-event systems." [Ames, Iowa : Iowa State University], 2009.
Find full textKammoun, Abderrahmen. "Enhancing Stream Processing and Complex Event Processing Systems." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSES012.
Full textAs more and more connected objects and sensory devices are becoming part of our daily lives, the sea of high-velocity information flow is growing. This massive amount of data produced at high rates requires rapid insight to be useful in various applications such as the Internet of Things, health care, energy management, etc. Traditional data storage and processing techniques are proven inefficient. This gives rise to Data Stream Management and Complex Event Processing (CEP) systems.This thesis aims to provide optimal solutions for complex and proactive queries. Our proposed techniques, in addition to CPU and memory efficiency, enhance the capabilities of existing CEP systems by adding predictive feature through real-time learning. The main contributions of this thesis are as follows:We proposed various techniques to reduce the CPU and memory requirements of expensive queries. These operators result in exponential complexity both in terms of CPU and memory. Our proposed recomputation and heuristic-based algorithm reduce the costs of these operators. These optimizations are based on enabling efficient multidimensional indexing using space-filling curves and by clustering events into batches to reduce the cost of pair-wise joins.We designed a novel predictive CEP system that employs historical information to predict future complex events. We proposed a compressed index structure, range query processing techniques and an approximate summarizing technique over the historical space.The applicability of our techniques over the real-world problems presented has produced further customize-able solutions that demonstrate the viability of our proposed methods
Mohror, Kathryn Marie. "Scalable event tracking on high-end parallel systems." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/2811.
Full textAnozie, Chidi H. "Event-Triggered Design of Networked Embedded Automation Systems." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1291754351.
Full textEstrada, Vargas Ana Paula. "Black-Box identification of automated discrete event systems." Thesis, Cachan, Ecole normale supérieure, 2013. http://www.theses.fr/2013DENS0006/document.
Full textThis thesis deals with the identification of automated discrete event systems (DES) operating in an industrial context. In particular the work focuses on the systems composed by a plant and a programmable logic controller (PLC) operating in a closed loop- the identification consists in obtaining an approximate model expressed in interpreted Petri nets (IPN) from the observed behaviour given under the form of a single sequence of input-output vectors of the PLC. First, an overview of previous works on identification of DES is presented as well as a comparative study of the main recent approaches on the matter. Then the addressed problem is stated- important technological characteristics of automated systems and PLC are detailed. Such characteristics must be considered in solving the identification problem, but they cannot be handled by previous identification techniques. The main contribution in this thesis is the creation of two complementary identification methods. The first method allows constructing systematically an IPN model from a single input-output sequence representing the observable behaviour of the DES. The obtained IPN models describe in detail the evolution of inputs and outputs during the system operation. The second method has been conceived for addressing large and complex industrial DES- it is based on a statistical approach yielding compact and expressive IPN models. It consists of two stages- the first one obtains, from the input-output sequence, the reactive part of the model composed by observable places and transitions. The second stage builds the non observable part of the model including places that ensure the reproduction of the observed input-output sequence. The proposed methods, based on polynomial-time algorithms, have been implemented in software tools, which have been tested with input-output sequences obtained from real systems in operation. The tools are described and their application is illustrated through two case studies
David-Henriet, Xavier. "Discrete Event Systems with Standard and Partial Synchronizations." Thesis, Angers, 2015. http://www.theses.fr/2015ANGE0010/document.
Full textMany transportation networks can be modeled by (max,+)-linear systems, i.e., discrete event systems ruled by standard synchronizations (conditions of the form: "for all k>=l, occurrence k of event B is at least t units of time after occurrence k-l of event A"). In some applications, it is also necessary to model simultaneity between events (e.g., for a road equipped with traffic lights, a vehicle can cross an intersection only when the associated traffic light is green). Such conditions cannot be expressed using standard synchronizations. Hence, we introduce the partial synchronization (condition of the form: "event B can only occur when event A occurs"). In this thesis, we consider a class of discrete event systems ruled by standard and partial synchronizations, called (max,+)-systems with partial synchronization. Such systems are split into a main system and a secondary system such that there exist only standard synchronizations between events in the same system and partial synchronizations of events in the secondary system by events in the main system. We adapt some modeling and control approaches developed for (max,+)-linear systems to (max,+)-systems with partial synchronization. Optimal feedforward control and model predictive control for (max,+)-linear systems are extended to (max,+)-systems with partial synchronization. Furthermore, transfer relation and model reference control are provided for the secondary system under a predefined behavior of the main system
Widebäck, West Nikolaus. "Multiple Session 3D Reconstruction using RGB-D Cameras." Thesis, Linköpings universitet, Datorseende, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112799.
Full textAbdelrahim, Mahmoud. "Output feedback event-triggered control." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0110/document.
Full textEvent-triggered control is a sampling paradigm in which the sequence of transmission instants is determined based on the violation of a state-dependent criterion and not a time-driven clock. In this thesis, we deal with event-triggered output-based controllers to stabilize classes of nonlinear systems. The contributions of the presented material are threefold: (i) we stabilize a class of nonlinear systems by using an emulation-based approach; (ii) we develop a co-design procedure to simultaneously design the output feedback law and the event-triggering condition for linear systems; (iii) we propose stabilizing event-triggered controllers for nonlinear systems whose dynamics have two-time scales (in particular, we only rely on the knowledge of an approximate model of the slow dynamics)
Sampath, Sreedevi. "Cost-effective techniques for user-session-based testing of Web applications." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.02 Mb., 169 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3220722.
Full textPålsson, Jonatan. "Querying Federations of Eiffel Event Data Repositories." Thesis, Linköpings universitet, Databas och informationsteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-169138.
Full textGardner, Robert David. "Event handling techniques in high speed networks." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248548.
Full textMyadzelets, Dmitry <1974>. "Discrete Event Systems based Design Patterns for Diagnosability Analysis of Automated Manufacturing Systems." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6335/.
Full textEgilsson, Guðlaugur Stefán. "Event Models : An Evaluation Framework." Thesis, University of Skövde, Department of Computer Science, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-389.
Full textEvent based programming is an important metaphor used in a variety of applications. Research and practice in this field comes primarily from two distinct sources, component software and databases. In both those fields, the need for asynchronous notifications has led to the specification and implementation of event models, but with somewhat different emphasis.
This dissertation defines an evaluation framework for evaluating event models. In doing so, it defines several factors that are important when reviewing different event models with respect to implementing applications or components that require event notification mechanisms.
It has been suggested that the event models defined for COM and CORBA can each be used as the basis for implementing advanced event services. The framework presented in this dissertation is used to evaluate these two event models with respect to their capability to support an advanced event service originating from active database research.
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.
Full textPosse, Ernesto. "Modelling and simulation of dynamic-structure discrete-event systems." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22006.
Full textLa modélisation et la simulation à événements discrets constituent une approche bien établie pour la description et l'étude des systèmes dynamiques complexes. Ces dernières années, il y a eu un regain d'intérêt pour la modélisation des systèmes complexes à structure dynamique. Ces systèmes sont généralement plus difficiles à comprendre et à analyser que les systèmes ayant une structure statique. Cette analyse et cette compréhension peuvent être développées à l'aide de formalismes de modélisation fondés sur une base solide et des outils appropriés. Dans cette thèse, nous explorons une approche de modélisation et de simulation des systèmes à événements discrets fondée sur l'algèbre de processus. Ce document se compose de deux parties. Dans la première partie, nous étudions ce que l'on appelle le formalisme Discrete-EVent System Specifications (DEVS.) Nous développons un autre fondement théorique pour DEVS fondée sur la sémantique opérationnelle structurelle, en mettant l'accent sur les propriétés de déterminisme et de compositionalité. Dans la deuxième partie, nous développons un langage de modélisation pour systèmes à structure dynamique nommé kiltera, en nous fondant sur les algèbres de processus et en incorporant des éléments de modélisation à événements discrets. Ce langage, en se fondant sur le \pi-calcul, nous permet de décrire et de raisonner sur les systèmes mobiles, distribués et au temps-réel, à événements discrets, dans un cadre conceptuel unique. Nous développons une base théorique fondée sur la sémantique opérationnelle structurelle et nous établissons des propriétés fondamentales concernant le déterminisme-temps, la continuité, la compositionalité et la légitimité. Nous construisons un simulateur pour le langage qui supporte à la fois l'exécution séquentielle et distribuée de modèles, en utilisant une variante de l'algorithme Time Warp. Enfin, nous appliquons ce la
Rönn, Pernilla. "Two Approaches to Event Detection in Active Database Systems." Thesis, University of Skövde, Department of Computer Science, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-628.
Full textAn active database management system can react to predefined events in the database, resulting in performing some appropriate action. ECA-rules are used to capture these predefined events and to express the appropriate action in the active database management system. An event is said to be an atomic occurrence and is either primitive or composite. D-SNOOP and O-SNOOP are two ways to describe the semantics of composite events. D-SNOOP is detection-based (an event is considered to be instantaneous) and O-SNOOP occurrence-based (an event is considered to occur over a time interval). Some problems concerning the detection of composite events using D-SNOOP semantics have been highlighted by Galton and Augusto (2001), who have created the O-SNOOP semantics to rectify some of the shortcomings of D-SNOOP. It is, however, not known what practical consequences O-SNOOP has on applications. To find some of these practical consequences, an advanced application that uses composite events must be used. In this work, the advanced application is a cooperative information system.
A cooperative information system is a system in which several agents work together to solve some common problem. The agents can take on a role as either manager (service requester) or agent (problem solver).
In this dissertation an investigation of the differences between O-SNOOP and D-SNOOP in applications handling cooperation protocols is presented. Our first objective has been to model a cooperation protocol using in turn the D-SNOOP and the O-SNOOP semantics. A further objective has been to compare the models of the cooperation protocols to identify any differences between using D-SNOOP and O-SNOOP semantics in applications handling cooperation protocols.