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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Deducing Basic Graph Patterns from Logs of Linked Data Providers / Déduire des Basic Graph Patterns depuis les Logs des fournisseurs du Linked Data

Nassopoulos, Georges 22 May 2017 (has links)
Conformément aux principes de Linked Data, les fournisseurs de données ont publié des milliards de faits en tant que données RDF. Exécuter les requêtes SPARQL sur les endpoints SPARQL ou les serveurs Triple Pattern Fragments (TPF) permet de consommer facilement des données du Linked Data. Cependant, le traitement des requêtes SPARQL fédérées, tout comme le traitement des requêtes TPF, décompose la requête initiale en de nombreuses sous-requêtes. Les fournisseurs de données ne voient alors que les sous-requêtes et la requête initiale n’est connue que des utilisateurs finaux. La connaissance des requêtes exécutées est fondamentale pour les fournisseurs, afin d’assurer un contrôle de l’utilisation des données, d’optimiser le coût des réponses aux requêtes, de justifier un retour sur investissements, d’améliorer l’expérience utilisateur ou de créer des modèles commerciaux à partir de tendances d’utilisation. Dans cette thèse, nous nous concentrons sur l’analyse des logs d’exécution des serveurs TPF et des endpoints SPARQL pour extraire les Basic Graph Patterns (BGP) des requêtes SPARQL exécutées. Le principal défi pour l’extraction des BGPs est l’exécution simultanée des requêtes SPARQL. Nous proposons deux algorithmes : LIFT et FETA. Sous certaines conditions, nous constatons que LIFT et FETA sont capables d’extraire des BGPs avec une bonne précision et un bon rappel. / Following the principles of Linked Data, data providers published billions of facts as RDF data. Executing SPARQL queries over SPARQL endpoints or Triple Pattern Fragments (TPF) servers allow to easily consume Linked Data. However, federated SPARQL query processing and TPF query processing decompose the initial query into subqueries. Consequently, the data providers only see subqueries and the initial query is only known by end users. Knowing executed SPARQL queries is fundamental for data providers, to ensure usage control, to optimize costs of query answering, to justify return of investment, to improve the user experience or to create business models of usage trends. In this thesis, we focus on analyzing execution logs of TPF servers and SPARQL endpoints to extract Basic Graph Patterns (BGP) of executed SPARQL queries. The main challenge to extract BGPs is the concurrent execution of SPARQL queries. We propose two algorithms: LIFT and FETA. LIFT extracts BGPs of executed queries from a single TPF server log. FETA extracts BGPs of federated queries from a log of a set of SPARQL endpoints. For experiments, we run LIFT and FETA on synthetic logs and real logs. LIFT and FETA are able to extract BGPs with good precision and recall under certain conditions.
62

Enhancement of inventory management system.

January 1998 (has links)
by Chung Chun Hung. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 65-66). / ABSTRACT --- p.ii / TABLE OF CONTENTS --- p.iv / LIST OF TABLES --- p.v / ACKNOWLEDGMENTS --- p.vi / Chapter / Chapter I. --- INTRODUCTION --- p.1 / Company Background --- p.2 / Chapter II. --- OBJECTIVE & METHODOLOGY --- p.7 / Objective --- p.7 / Methodology --- p.7 / Chapter III. --- CURRENT INVENTORY MANAGEMENT PROBLEMS & CAUSES --- p.9 / Chapter IV. --- APPLICATION OF ANALYTICAL TOOLS IN INVENTORY MANAGEMENT --- p.13 / Demand Forecasting --- p.14 / Forecast Evaluation --- p.17 / Result Analysis --- p.18 / Inventory Management for Individual Items --- p.20 / Safety Stock & Reorder Point --- p.20 / Economic Order Quantity --- p.23 / Multiple-Item Management --- p.25 / Multiple Item ABC Analysis --- p.25 / Replenishment Order for Multiple Items --- p.21 / Chapter V. --- RECOMMENDATIONS & CONCLUSIONS --- p.32 / APPENDIX --- p.36 / BIBLIOGRAPHY --- p.65
63

Arms control : a strategic concession bargaining solution

Qi, Yun 01 January 2006 (has links)
No description available.
64

Influence de l'infrastructure routière sur l'occurrence des pertes de contrôle des véhicules légers en virage : modélisation et validation sur site expérimental / Road infrastructure influence on the occurrence of control loss of lightweight vehicles in curves : modelisation and validation on test track

Orfila, Olivier 12 October 2009 (has links)
L’infrastructure routière joue un rôle très important dans l’occurrence des pertes de contrôle des véhicules légers en virage. Dans le but d’évaluer le niveau de risque associé à une infrastructure, les gestionnaires routiers utilisent actuellement des méthodes reposant sur des études statistiques ou empiriques, sachant que leur validité peut évoluer au cours temps. Le but de ces travaux est donc de compléter ces méthodes par une évaluation physique des tracés routiers basée sur la dynamique des véhicules. Tout d’abord, le problème a été abordé de manière théorique par une écriture de critères issus des modèles de la dynamique des véhicules (modèles point et bicyclette) visant à identifier et quantifier l’impact des paramètres routiers sur l’occurrence des pertes de contrôle. Ensuite, pour représenter avec plus de précision le comportement du conducteur, une modélisation numérique complète de contrôle du système véhicule-infrastructure-conducteur, basée sur un algorithme génétique, a été mise en œuvre. Enfin, ces deux approches ont été validées expérimentalement pour différentes adhérences, rayons de courbure et véhicules sur la piste de référence du LCPC de Nantes et sur routes interurbaines et urbaines. Ces travaux de thèse ont permis d’approfondir la connaissance du rôle de l’infrastructure et de développer deux méthodes (analytique et numérique) d’évaluation des tracés routiers. En perspectives à cette étude, un logiciel basé sur ces méthodes sera développé. / Road infrastructure plays a major role in the occurrence of control loss of lightweight vehicles in curves. To evaluate the risk level associated with an infrastructure, road managers are currently using methods founded on statistical or empirical studies, knowing that their reliability can vary over time. The aim of this work is to complete these methods with a physical evaluation of road plans based on vehicle dynamics. First of all, the problem has been dealt on the theoretical way by writing criteria coming from vehicle dynamic models (point and bicycle models) aiming to identify and quantify the influence of road parameters on control loss occurrence. Then, to faithfully take into account the driver behaviour, a complete numerical modelling of the vehicle-infrastructure-driver, resting on a genetic algorithm, has been introduced. Finally, these two approaches has been validated for various grip, curvature radius and vehicles on the LCPC test track in Nantes and on interurban and urban roads. These thesis works has permitted to improve the knowledge of road infrastructure influence and to develop two road plan evaluation methods (analytical and numerical). As a prospect of this study, a software based on these two methods will be developed.
65

Learning to control

Potts, Duncan, Computer Science & Engineering, Faculty of Engineering, UNSW January 2007 (has links)
This thesis examines whether it is possible for a machine to incrementally build a complex model of its environment, and then use this model for control purposes. Given a sequence of noisy observations, the machine forms a piecewise linear approximation to the nonlinear dynamic equations that are assumed to describe the real world. A number of existing online system identification techniques are examined, but it is found that they all either scale poorly with dimensionality, have a number of parameters that make them difficult to apply, or do not learn sufficiently accurate approximations. Therefore a novel framework is developed for learning linear model trees in both batch and online settings. The algorithms are evaluated empirically on a number of commonly used benchmark datasets, a simple test function, and three dynamic domains ranging from a simple pendulum to a complex flight simulator. The new batch algorithm is compared with three state-of-the-art algorithms and is seen to perform favourably overall. The new incremental model tree learner also compares well with a recent online function approximator from the literature. Armed with a tool for effectively constructing piecewise linear models of the environment, a control framework is developed that learns trajectories from a demonstrator and attempts to follow these trajectories within each linear region usinglinear quadratic control. The induced controllers are able to swing up and balance a simple forced pendulum both in simulation and in the real world. They can also swing up and balance a real double pendulum. The induced controllers are empirically shown to perform better than the original demonstrator, and could therefore be used to either replace a human operator or improve upon an existing automatic controller. In addition an ability to generalise the learnt trajectories enables the system to perform novel tasks. This is demonstrated on a flight simulator where, having observed an aircraft flying several times around a circuit, the controller is able to copy the take-off procedure, fly a completely new circuit that includes new manoeuvres, and successfully land the plane.
66

Development of collaborative order processing and inventory tracing software

Singh, Gaurav, January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 130 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 78-80).
67

Receding horizon control of air operation resource allocation

Ruschmann, Matthew Charles. January 2006 (has links)
Thesis (M.S.)--State University of New York at Binghamton, Dept. of Electrical & Computer Engineering, 2006. / Includes bibliographical references.
68

Perspectives in modern control theory

January 1976 (has links)
by Michael Athans. / Bibliography: leaves 33-36. / Prepared under ONR Contract N00014-76-C-0346.
69

Applying and analyzing robust modern control on uncertain hydraulic systems

Bax, Brian. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 5, 2007) Includes bibliographical references.
70

Replenishing routing under vendor managed inventory systems /

Li, Jing An. January 2006 (has links) (PDF)
Thesis (Ph.D.)--City University of Hong Kong, 2006. / "Submitted to Department of Management Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy" Includes bibliographical references (leaves 118-132)

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