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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.
121

Impact des impulsions périodiques de courant sur la performance et la durée de vie des accumulateurs lithium-ion et conséquences de leur mise en oeuvre dans une application transport / Impact of periodic current pulses on the performance and the lifetime of Lithium-ion batteries and the consequences on its processing in vehicular applications

Savoye, François Paul 01 March 2012 (has links)
Ce travail vise à identifier l’impact potentiel des impulsions périodiques de courant sur laperformance et la durée de vie des accumulateurs graphite/LiFePO4. Il apparait que,contrairement aux résultats connus pour les accumulateurs Plomb-acide et à ceux annoncéspar certains auteurs de la littérature pour les accumulateurs Li-ion, l’application d’impulsionspériodiques de courant ne présente pas d’intérêt dans une logique d’amélioration de laperformance et/ou de la durée de vie des accumulateurs Li-ion. De surcroit, certains typesd’impulsions ont été identifiés pour entrainer des effets préjudiciables à ces derniers. En seréférant à une application de véhicule industriel hybride électrique, nous avons évalué sur descritères techniques et économiques l’intérêt d’implémenter un système de stockage d’énergiecombiné, c'est-à-dire mutualisant l’usage d’une batterie Li-ion et desupercondensateurs/condensateurs. Il apparait que les stratégies consistant à agir sur lescomposantes hautes fréquences du signal pour ajouter/retirer des impulsions du profil vu parla batterie ne permettent pas d’accéder à des allongements de durée de vie qui pourraientcompenser le surcoût actuel lié à l’implémentation de ces systèmes. En outre, il apparait quele meilleur levier d’optimisation du bilan technique et économique associé au système destockage d’énergie est son dimensionnement. En effet, même si les systèmes de stockaged’énergie combinés utilisant les supercondensateurs permettent d’atteindre des réductions duratio coût/durée de vie considérables, la prise en compte globale des critères de coût, de duréede vie, de masse et d’encombrement s’avère plus favorable à la solution constituée d’unebatterie seule, de taille optimisée vis-à-vis de son application. / This work aims to identify the possible impact of periodic current pulses on both performanceand lifetime of graphite/LiFePO4 secondary batteries. Contrary to the well-known results onlead-acid batteries and to results announced in previously published works, periodic pulses donot bring any benefit to the performance and the lifetime of Li-ion batteries. Moreover,certain pulse types have been identified to be detrimental to Li-ion batteries. Using the hybridelectric vehicle application as a reference, we evaluated both the technical and economicalaspects of implementing combined energy storage systems composed with Li-ion batteriesand supercapacitors/capacitors. We found that the control strategies acting on high frequencyharmonics of the current signal to adding/retrieving pulses to the Li-ion battery profile doesnot prolong its life enough to compensate the extra cost of such system implementation.Furthermore, it seems that the best way to optimize the technico-economic balance of theenergy storage system is the sizing. Even if combined energy storage systems using Li-ionbatteries and supercapacitors enable to considerably increase the lifetime/cost ratio, a generalconsideration of the criteria cost, life, mass and volume is more favorable to a solution whereone single Li-ion battery is optimally sized for its application.
122

Research on system architecture for device and content independent applications including 3d imaging and virtual reality as content / Recherche sur système de l'architecture pour dispositif et contenu indépendant, applications, y compris 3D l'imagerie et la réalité virtuelle comme contenu

Sultana, Razia 30 September 2014 (has links)
Les réseaux traitant l’information, intègrent différentes technologies incluant une large gamme de dispositifs aux capacités et puissances très variées et capables de gérer une immense quantité d’informations sous forme de données d’une grande diversité de formats. La recherche sur l'imagerie 3D, la réalité virtuelle et autres techniques holographiques permettront d’offrir de nouvelles techniques d’interactions homme/machine (IHM), notamment pour les appareils mobiles. Cela enrichira encore la variété et la diversité de ces dispositifs. Beaucoup d'efforts ont été faits, notamment ces dernières années, afin d’établir une intégration ouverte, évolutive et transparente des différentes technologies permettant l’affichage de contenus, notamment d’images 2D et 3D et ce pour tout type de système, y compris mobile en tenant compte, notamment et de plus en plus, de la situation géographique individuelle de l'utilisateur final. Sur ces différents points, la tâche est loin d’être terminée. Cette thèse représente, dans ce contexte, une contribution, vers la généralisation de la transportabilité des informations pour des objets communicants de natures différentes, notamment portables, particulièrement dans le cas de l’imagerie en 3 dimensions, de plus en plus exploitée.L'objectif de ce travail de recherche est de trouver un moyen de résoudre le problème énoncé ci-dessus en proposant une architecture pour fournir un accès sans contrainte, continu et personnalisé pour le contenu et les applications interactives partout et à tout moment avec la plus grande quantité possible d’appareils communicants. Un exemple d’exploitation utile et particulièrement adaptée d'un tel système est l'apprentissage sur mobile en raison de la grande diversité des appareils communicants disponibles, dotés de caractéristiques et de fonctionnalités très différentes. Comme solution au problème considéré, une nouvelle architecture nommée "Smoothie" est proposée, un prototype a été développé et évalué en tant que composant important d'un jeu d'apprentissage collaboratif de langues étrangères nommé LLG (Language Learning Game). / Today’s network landscape consists of many different network technologies, a wide range of end-devices with large scale of capabilities and power, an immense quantity of information and data represented in different formats. Research on 3D imaging, virtual reality and holographic techniques will result in new user interfaces (UI) for mobile devices and will increase their diversity and variety. A lot of effort is being made in order to establish open, scalable and seamless integration of various technologies and content presentation for different devices including those that are mobile, considering the individual situation of the end user. Till today the research is going on in different parts of the world but the task is not completed yet.The goal of this research work was to find a way to solve the above stated problems by investigating system architectures to provide unconstrained, continuous and personalized access to the content and interactive applications everywhere and at anytime with different devices. As a Solution of the problem considered, a new architecture named “Smoothie” is proposed, developed as prototype and evaluated as an important feature of a collaborative foreign language learning game named LLG.
123

Dependable cognitive wireless networking:modelling and design

Celentano, U. (Ulrico) 06 June 2014 (has links)
Abstract Radio communication is used in increasingly diversified device typologies. Telecommunications with a reduced detrimental impact on health and environment, and an improved cost-efficiency and working lifetime are expected by institutions, end-users, operators and manufacturers. Moreover, with more networks present or more articulated systems, dependability of the entirety is to be ensured. The related need of efficiency in various compartments – such as in the use energy or the radio spectrum – and of effectiveness in adapting to changing operating conditions can be achieved with cognitive features. This dissertation addresses network reconfiguration and dependability by cognitive measures from multiple perspectives – each covered by a respective part of this work – providing guidelines for cognitive networks design. A rationalising view on cognitive networks with related taxonomies and models includes a discussion on the dynamics and interactions in networks operating closely and simultaneously (here, concurrent networks). While cognitive domains are specified for cognitive functions, with a more generic scope control functions are assigned to topological domains. This allows a flexible exploitation of the system design by decoupling the specification of system functions from their mapping onto network devices that will host them. As interaction plays an important role in many topical scenarios, a model for networked engineered cognitive entities comprising four categories (observation, interworking, consolidation, operation) and two levels (a cognitive frontier and a metacognitive hub) is presented here. Its cognitive phases are considered with regard to the other architectural elements. Moving the focus down to the levers for exploitation of context awareness, are presented solutions for efficient use of resources and dependability in general, considering the network dynamics. For communication link and network adaptation, the effective capacity is captured by a compact-form expression also considering imperfections, while learning is exploited for reducing overhead, and collaboration for fairly maximising energy save. / Tiivistelmä Käyttäjät, operaattorit ja laitevalmistajat toivovat tulevilta tietoliikennejärjestelmiltä sekä aiempaa pienempiä haitallisia vaikutuksia terveyteen ja ympäristöön että parannettua kustannustehokkuutta ja toiminta-aikaa. Lisäksi olisi varmistettava useiden verkkojen ja niiden muodostamien monimutkaisten järjestelmien kokonaisuuden luotettava toiminta. Tarvittava tehokkuus energian ja radioresurssien käytössä, samoin kuin kyky sopeutua muuttuviin käyttötilanteisiin, voidaan saavuttaa kognitiivisilla radioteknikoilla. Tämä väitöskirja käsittelee kognitiivisten menetelmien tuomaa radioverkkojen mukauttamista ja luotettavuutta eri näkökulmista. Samalla esitetään kognitiivisten verkkojen suunnittelun periaatteita ja lähtökohtia. Väitöskirja sisältää katsauksen kognitiivisiin radioverkkoihin niihin liittyvine luokitteluineen ja malleineen, sekä tarkastelee samanaikaisesti ja läheisesti toimivien verkkojen (rinnakkaisten verkkojen) dynamiikkaa ja vuorovaikutuksia. Työssä määritetään kognitiiviset lohkot kognitiivisine toimintoineen, kun taas topologiset tasot hallintatoimintoineen määritetään yleisemmin. Tämä mahdollistaa järjestelmäsuunnittelun joustavan hyödyntämisen erottamalla järjestelmän toimintojen määrittelyn toteuttavista verkkolaitteista. Koska vuorovaikutus on merkittävä tekijä useissa sovellusskenaarioissa, verkottuneille keinotekoisille kognitiivisille yksiköille ehdotetaan tässä neljä luokkaa (havainnointi, yhteistoiminta, vakauttaminen, toiminta) sekä kaksi vyöhykettä (kognitiivinen raja-alue ja metakognitiivinen keskus) sisältävää mallia. Mallin kognitiiviset vaiheet käsitellään suhteessa muihin arkkitehtuurin elementteihin. Järjestelmän kontekstitietoisuuden hyväksikäyttöön liittyen esitetään ratkaisuja resurssien tehokkaaseen käyttöön ja yleisemmin luotettavuuteen ottaen huomioon verkkojen dynamiikkaa. Yhteyksien ja verkkojen mukauttamisesta esitetään analyyttinen ratkaisu saavutettavan tehollisen kapasiteetin määrittämiseksi, huomioiden mahdolliset epäideaalisuudet. Kognitiivista oppimista hyödynnetään hallintalikenteen vähentämiseksi ja yhteistyötä energiansäästön maksimoimiseksi verkon alueella tasapuolisesti.
124

Implementace informačního modelu v prostředí systémové architektury / Information model implementation in systems architecture

Pořádek, Jiří January 2013 (has links)
This thesis deals with a field of information modeling and its relation to systems architecture. It is divided into two notional parts -- theoretical (first and second chapter) and practical (third and fourth chapter). First chapter explains the meaning of the term 'information model', compares it to the term 'data model' and then introduce its practical use in an enterprise modeling. It also defines the term of 'systems architecture' in its broad meaning and reduces it to three narrow meaning -- enterprise architecture, information architecture and information systems architecture, while it explains their relation to the information modeling. Finally this chapter provides the base for information model implementation methodology created later in the practical part of this thesis. Second chapter introduces architecture framework called TM Forum Frameworx specialized for a telecommunication services provider. It consists of three standards for business process, information and application architecture. The second one defines specific information model which is described partly in the second chapter and partly in the appendix B of this thesis. Third chapter describes the first of two contributions of this thesis - the information model implementation methodology. This methodology is applicable to any implementation of an information model. Three sections of this chapter contains diagrams and description of three phases of the methodology - pre-implementation phase, implementation phase and post-implementation phase. In the end of the chapter there is a table containing outputs of every single activity performed during all the phases. Fourth and last chapter then describes and evaluates real implementation of the information model from TM Forum Frameworx in the systems architecture department of an enterprise providing telecommunication services. This implementation based on the created methodology and its successful results then became the second contribution of this thesis.
125

Záznamového zařízení pro oblast civilního letectví / Data storage system for area of civil aviation

Kotulič, Dominik January 2018 (has links)
In the thesis the design of the Data Storage System (DSS) is proposed with the respect to the V-Model methodology. The design is based on users requirements, from which the system requirements are created and the technical specification of the DSS is developed. In the technical specifications the functionality of the DMM and HMI DSS subsystems are described and sub-system requirements are assigned to them, then they are subdivided and assigned to individual DMM (Data memory module) and HMI hardware items. Moreover, requirements are analyzed on hardware items, specific electronic components, are selected and implemented into the block design of the DMM hardware. Based on the block design of hardware, the hardware of the DMM subsystem is designed, selectively simulated and implemented along with the printed circuit board. On the implemented hardware of the DMM subsystems measurements are performed in order to verify the basic functionality of the hardware and the calculated, assimilated and measured values are compared as well. At the end of the thesis there is a short description of the implementation of the software design and its use for basic initialization of the selected processor, together with the verification of its basic function - measuring the frequency of the internal clock sources and the clock domains. The work is completed by sending a message of defined parameters to the selected communication line and sapling it by an oscilloscope, so that the basic function of the DMM subsystem is verified.
126

Návrh distribuovaného systému pro zpracování školní matriky ZŠ, SŠ, VOŠ / Distributed System for School Register of Basic and Secondary Schools

Martiš, Viktor Unknown Date (has links)
One of the software success condition on the software market is permanent development to keep in condition with actual technical tools. That is the reason why SAS software is searching for a way how to fulfil customer's requirements better. The change to the distributed system architecture brings new opportunities and sets up competitive advantage for SAS concurrently. The subject of this thesis is to create the design of movement to the distributed system. The main reason is to make analysis, design and partial implementation meeting functional requirements of the new architecture.
127

Entwicklung und Abstimmung eines Momentenmodells für eine Otto-DI-Motorsteuerung

Pietzsch, Albrecht 18 December 2017 (has links)
Die Zulieferindustrie im Automobilbereich sieht sich heutzutage hochkomplexen Systemen bei der Entwicklung von Verbrennungsmotoren gegenüber. Applikationssteuergeräte mit passendem Datenstand werden selten von Fahrzeugherstellern an Dritte für die Entwicklung am Verbrennungsmotor bereitgestellt. Eine Alternative bieten Prototypensteuergeräte mit individuellen Softwarepaketen, die in ihrer Funktionalität auf die Bedürfnisse der Entwicklungsingenieure zugeschnitten sind. Die FlexECU von ETAS ist ein gutes Beispiel für solch ein offenes, kostengünstiges und seriennahes Prototypensteuergerät. Hauptbestandteil dieser Arbeit ist die Entwicklung und Integration eines Momentemodells in eine vorhandene Motorsteuerungssoftware sowie die Applikation dieses Modells am Motorprüfstand. Die Motivation für die Erweiterung der jetzigen Motorsteuerungssoftware um das Momentemodell ist, den Entwicklungsingenieuren ein möglichst seriennahes Steuergeräteumfeld bei der Erarbeitung innovativer verbrauchs- und schadstoffoptimierter Konzepte für den Verbrennungsmotor bereitzustellen. Bei der Evaluation wird gezeigt, dass die Integration und die Funktion des Momentenmodells grundsätzlich gelungen ist. Diese Arbeit bildet den Grundstein für eine umfangreiche Entwicklung, die noch einige Zeit in Anspruch nehmen wird, bis eine voll umfängliche abgesicherte Software geschaffen ist.:Abkürzungsverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I Verzeichnis der Formelzeichen und Symbole . . . . . . . . . . . . . . . II Variablenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .V Abbildungsverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VII Tabellenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .VIII 1. Einleitung 1 1.1. Aufgabenstellung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 1.2. Zielsetzung und Aufbau der Arbeit . . . . . . . . . . . . . . . . . . .1 2. Stand der Technik 4 2.1. Steuerung und Regelung von Ottomotoren . . . . . . . . . . . . 4 2.2. Architektur Motorsteuerungssoftware . . . . . . . . . . . . . . . . 7 2.3. Das Momentenmodell . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3. Theoretische Grundlagen 15 3.1. Innermotorische Drehmomentenerzeugung . . . . . . . . . . .15 3.2. Eingriffsmöglichkeiten und deren Geschwindigkeit . . . . . .18 4. Modellierung des Momentenmodells 20 4.1. Entwicklungsumgebung . . . . . . . . . . . . . . . . . . . . . . . . . .20 4.2. Modellbildung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 5. Versuch 34 5.1. Versuchsplanung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 5.2. Versuchsträger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 5.2.1. ETAS FlexECU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.2.2. Simulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.2.3. Versuchsmotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5.2.4. Motorprüfstand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40 5.3. Applikationssoftware . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 5.3.1. ETAS INCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42 5.3.2. ETAS MDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 5.3.3. ETAS ASCMO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 6. Vorstellung der Ergebnisse . . . . . . . . . . . . . . . . . . . . . . . . .45 6.1. Ergebnisse der Applikation des Momentemodells . . . . . . 45 6.2. Evaluierung der Drehmomentumsetzung des Momentenmodells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 6.3. Evaluierung der Untersysteme des Momentenmodells . . 62 7. Zusammenfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71 Literatur- und Quellenverzeichnis . . . . . . . . . . . . . . . . . . . . . 75 Eidesstattliche Erklärung . . . . . . . . . . . . . . . . . . . . . . . . . . . .76 Anlagenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 / Nowadays, the automotive supplier industry is confronted with highly complex systems for the development of internal combustion engines. Vehicle manufacturers very rarely provide third party developers with their engine control units with calibration access and matching description and data files for internal combustion engines. An alternative are prototype control units with individual software packages, which in their functionality are adapted to the needs of development engineers. One example for such an open, cost-effective and field-proven control system development platform is FlexECU from ETAS. The essential part of this thesis is the development and integration of a torque-based system structure for an existing engine management system and the calibration of this model on an engine test bench. The motivation for this improvement is to provide development engineers with a control unit environment as close to serial as possible for the development of consumption- and emission-optimized concepts for internal combustion engines. The evaluation shows that integration as well as functionality of the torque-based system structure has generally been achieved. This thesis lays the foundations for an extensive development of this system – although the creation of a fully verified and validated software will still take some time.:Abkürzungsverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I Verzeichnis der Formelzeichen und Symbole . . . . . . . . . . . . . . . II Variablenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .V Abbildungsverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VII Tabellenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .VIII 1. Einleitung 1 1.1. Aufgabenstellung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 1.2. Zielsetzung und Aufbau der Arbeit . . . . . . . . . . . . . . . . . . .1 2. Stand der Technik 4 2.1. Steuerung und Regelung von Ottomotoren . . . . . . . . . . . . 4 2.2. Architektur Motorsteuerungssoftware . . . . . . . . . . . . . . . . 7 2.3. Das Momentenmodell . . . . . . . . . . . . . . . . . . . . . . . . . . . .11 3. Theoretische Grundlagen 15 3.1. Innermotorische Drehmomentenerzeugung . . . . . . . . . . .15 3.2. Eingriffsmöglichkeiten und deren Geschwindigkeit . . . . . .18 4. Modellierung des Momentenmodells 20 4.1. Entwicklungsumgebung . . . . . . . . . . . . . . . . . . . . . . . . . .20 4.2. Modellbildung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 5. Versuch 34 5.1. Versuchsplanung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 5.2. Versuchsträger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37 5.2.1. ETAS FlexECU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.2.2. Simulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 5.2.3. Versuchsmotor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 5.2.4. Motorprüfstand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40 5.3. Applikationssoftware . . . . . . . . . . . . . . . . . . . . . . . . . . . .41 5.3.1. ETAS INCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42 5.3.2. ETAS MDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 5.3.3. ETAS ASCMO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43 6. Vorstellung der Ergebnisse . . . . . . . . . . . . . . . . . . . . . . . . .45 6.1. Ergebnisse der Applikation des Momentemodells . . . . . . 45 6.2. Evaluierung der Drehmomentumsetzung des Momentenmodells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 6.3. Evaluierung der Untersysteme des Momentenmodells . . 62 7. Zusammenfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71 Literatur- und Quellenverzeichnis . . . . . . . . . . . . . . . . . . . . . 75 Eidesstattliche Erklärung . . . . . . . . . . . . . . . . . . . . . . . . . . . .76 Anlagenverzeichnis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
128

Gestion de contexte pour l'optimisation de l'accès et l'adaptation des services sur des environnements hétérogènes / Context management for network access optimisation and services adaptation in heterogeneous environments

Loukil, Mehdi 20 December 2012 (has links)
Dans le domaine des TIC, les services de demain seront certainement basés sur des systèmes ubiquitaires, omniprésents et pervasifs. Ces systèmes devront prendre en considération différents paramètres provenant de l’environnement de l’utilisateur, c’est à dire son contexte. Le contexte de l’utilisateur peut être composé d’informations statiques ou dynamiques, objectives ou subjectives, quantitatives ou qualitatives. Il peut inclure des données telles que la localisation géographique, les caractéristiques du terminal utilisé, la température ambiante, l’humeur de l’utilisateur. Afin d’améliorer la QoS et la QoE, les services et les systèmes doivent être adaptés aux changements du contexte des utilisateurs. Le contexte doit donc être collecté et interprété et les règles d’adaptation du système doivent être définies. Sur les systèmes étendus, riches, dynamiques et hétérogènes, tels que ceux considéré dans le cadre de cette thèse, ces opérations doivent être automatisées. Vu la quantité et la complexité des données contextuelles à considérer, l’utilisation de la sémantique dans la gestion de contexte peut faciliter cette automatisation et ouvrir la porte au raisonnement et à l’adaptation automatiques. Aujourd’hui, peu de solutions viables existent pour cette problématique. Nous proposons alors d’utiliser et d’adapter des mécanismes et technologies provenant du web sémantique pour décrire et manipuler les informations de contexte. Dans un premier temps, nous avons proposé une méthodologie de conception qui nous permit de proposer « Ubiquity-Ont » : une ontologie générique au domaine des TIC, flexible et extensible. Les données de contexte ont alors été décrites sous forme de concepts et d’instances, reliés par des relations sémantiques. Nous avons ensuite proposé une architecture overlay, composée de deux niveaux de vitalisation et permettant d’intégrer un gestionnaire de contexte, basé sur la sémantique, sur des environnements réseaux et services. Cette solution overlay permet de (a) masquer l’hétérogénéité des composants du système et (b) d’augmenter virtuellement les entités du système existant par les capacités nécessaires à la manipulation et au raisonnement sur les données sémantiques du contexte. Nos propositions ont étés implémentées et testées sur une plateforme réelle et appliquées à deux cas d’études : Gestion de la mobilité sur des environnements de réseaux d’accès hétérogènes et Optimisation de la consommation d’énergie dans les terminaux mobiles / Future Information and Telecommunication Systems are expected to be pervasive and ubiquitous solutions, able to consider users’ context and to automatically adapt to their environments. Traditional configuration and management tools are not adapted. The richness, the heterogeneity and the complexity of the upcoming systems require automated solutions able to gather contextual information, to reason on them and to make the appropriate adaptation decisions. The representation and the sharing of contextual information is a key issue. In this thesis, we proposed and used a methodology to conceive « Ubiquity-Ont », a generic ontology dedicated to Information and Telecommunication Systems. Contextual information are the described through semantic concepts, instances and relations. We then proposed an overlay architecture, composed of two virtualization layers that can integrate a semantic context management framework over existing networking environments. This architecture is able (a) to hide any heterogeneity among the system components and (b) to augment the different entities with additional capacities for context gathering, reasoning and sharing operations. The proposed solutions were then implemented and tested in Lab for two applications. The fisrt is related to mobility management over heterogeneous Wireless Networks and the second aims to power optimization on mobile terminals. These two case studies helped in proving and enhancing the proposed solutions
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Modernisering av mjukvaruarkitektur för äldre mjukvarusystem / Modernization of software architecture for legacy software systems

Saffo, Farah, Saeed, Basma January 2021 (has links)
Flera företag använder sig än idag av mjukvarusystem som är uppbyggda med äldre mjukvaruarkitektur som den monolitiska. Ett av dessa företag är Consid vars personalsystem är uppbyggt med det utdaterade ramverket klassisk ASP och där användargränssnitt samt logik kan direkt kommunicera med varandra. Detta medför begränsningar som uppstår till följd av brister i modularitet på grund av valet av mjukvaruarkitektur, vilket försvårar vidareutveckling och ändringar i ett system. Dessa begränsningar påverkar i sin tur parametrar som prestanda, skalbarhet, säkerhet, robusthet samt integrering med modernare tekniker.  I denna rapport presenteras en litteraturstudie samt en semistrukturerad intervjustudie, i syfte att undersöka vilka mjukvaruarkitekturer som är lämpliga att implementera vid en modernisering av en monolitisk mjukvaruarkitektur. Arbetet diskuterade också vilka utmaningar som kan uppstå vid en sådan modernisering och hur de hanteras på ett effektivt sätt. Ett bedömningsschema med önskvärda parametrar, med avseende på skalbarhet, prestanda, säkerhet och robusthet, togs fram för att underlätta avgörandet vid val av mjukvaruarkitektur. Utifrån detta, beslutades det att en prototyp med en REST-baserad arkitektur skulle implementeras och utvärderas.  Resultatet av prototypen, till följd av re-architecting, visade en ökad modularisering av mjukvaruarkitekturen. I jämförelse mot med det tidigare systemet har den nya prototypen ingen större påverkan på prestanda i form av responstid. Däremot bidrog prototypen till förbättrad skalbarhet när det gäller vidareutvecklingen av systemet, eftersom det förenklar införandet av ny funktionalitet. Prototypen hade också högre säkerhet genom att isolera lager ifrån varandra samt dölja underliggande detaljer i implementationen. Dessutom blev prototypen inte bara mer robust till följd av modulariseringen, men även enklare att utföra integrationstester samt destruktiva tester mot. / Several companies still use software systems that are built with older software architecture such as the monolithic one. One of these companies is Consid, whose personnel system is built with the outdated framework Classic ASP and where the user interface and logic can directly communicate with each other. This entails limitations that arise because of shortcomings in modularity due to the choice of software architecture, which complicates further development and changes in a system. These limitations in turn, affect parameters such as performance, scalability, security, robustness, and integration with modern technologies. In this work, a literature study was conducted as well as a semi-structured interview study in order to investigate which software architectures are suitable to implement when a modernization of a monolithic software architecture, is carried out. The work also discussed the challenges that may arise in a modernization of the software architecture and how they are handled efficiently. An assessment scheme with desirable parameters regarding scalability, performance, security, and robustness, was developed to facilitate the decision in the choice of software architecture. Based on this, it was decided that a prototype with a REST-based architecture would be implemented and evaluated. The result of the prototype, following re-architecting, showed an increased modularization of the software architecture. Compared to the previous system, the new prototype has no major impact on performance in terms of response time. However, the prototype contributed to better scalability in the further development of the system as it simplifies the introduction of new functionality. The prototype also had higher security by isolating layers from each other and hiding the underlying details in the implementation. In addition, the prototype not only became more robust because of the modularization, but also easier to perform destructive tests against.
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Advanced metering infrastructure reference model with automated cyber security analysis

Blom, Rikard January 2017 (has links)
European Union has set a target to install nearly 200 million smart metersspread over Europe before 2020, this leads into a vast increase of sensitiveinformation flow for Distribution System Operators (DSO’s), simultaneously thisleads to raised cyber security threats. The in and outgoing information of the DSOneeds to be processed and stored by different Information technology (IT)- andOperational Technology (OT)-systems depending on the information. High demandsare therefore required of the enterprise cyber security to be able to protect theenterprise IT- and OT-systems. Sensitive customer information and a variety ofservices and functionality is examples that could be fatal to a DSO if compromised.For instance, if someone with bad intentions has the possibility to tinker with yourelectricity, while you’re away on holiday. If they succeed with the attack and shuttingdown the house electricity, your food stored in your fridge and freezer would mostlikely to be rotted, additionally damage from defrost water leaking could cause severedamaging on walls and floors. In this thesis, a detailed reference model of theadvanced metering architecture (AMI) has been produced to support enterprisesinvolved in the process of implementing smart meter architecture and to adapt to newrequirements regarding cyber security. This has been conduct using foreseeti's toolsecuriCAD, foreseeti is a proactive cyber security company using architecturemanagement. SecuriCAD is a modeling tool that can conduct cyber security analysis,where the user can see how long time it would take for a professional penetrationtester to penetrate the systems in the model depending of the set up and defenseattributes of the architecture. By varying defense mechanisms of the systems, fourscenarios have been defined and used to formulate recommendations based oncalculations of the advanced meter architecture. Recommendation in brief: Use smalland distinct network zones with strict communication rules between them. Do diligentsecurity arrangements for the system administrator PC. The usage of IntrusionProtection System (IPS) in the right fashion can delay the attacker with a percentageof 46% or greater. / Europeiska Unionen har satt upp ett mål att installera nära 200miljoner smarta elmätare innan år 2020, spritt utöver Europa, implementeringen ledertill en rejäl ökning av känsliga dataflöden för El-distributörer och intresset av cyberattacker ökar. Både ingående och utgående information behöver processas och lagraspå olika IT- och OT-system beroende på informationen. Höga krav gällande ITsäkerhet ställs för att skydda till exempel känslig kundinformation samt en mängdvarierande tjänster och funktioner som är implementerade i systemen. Typer avattacker är till exempel om någon lyckats få kontroll over eltillgängligheten och skullestänga av elektriciteten till hushåll vilket skulle till exempel leda till allvarligafuktskador till följd av läckage från frysen. I den här uppsatsen så har en tillräckligtdetaljerad referens modell för smart elmätar arkitektur tagits fram för att möjliggörasäkerhetsanalyser och för att underlätta för företag i en potentiell implementation avsmart elmätare arkitektur. Ett verktyg som heter securiCAD som är utvecklat avforeseeti har använts för att modellera arkitekturen. securiCAD är ett modelleringsverktyg som använder sig av avancerade beräknings algoritmer för beräkna hur långtid det skulle ta för en professionell penetrationstestare att lyckats penetrera de olikasystem med olika sorters attacker beroende på försvarsmekanismer och hurarkitekturen är uppbyggd. Genom att variera systemens försvar och processer så harfyra scenarion definierats. Med hjälp av resultaten av de fyra scenarierna så harrekommendationer tagits fram. Rekommendationer i korthet: Använd små ochdistinkta nätverkszoner med tydliga regler som till exempel vilka system som fårkommunicera med varandra och vilket håll som kommunikationen är tillåten.Noggranna säkerhetsåtgärder hos systemadministratörens dator. Användningen avIPS: er, genom att placera och använda IPS: er på rätt sätt så kan man fördröjaattacker med mer än 46% enligt jämförelser mellan de olika scenarier.

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