Les logiciels dépendent de bibliothèques tierces pour réduire les coûts liés à leur développement et à leur maintenance. Elles proposent un ensemble de fonctionnalités robustes dont les développeurs peuvent tirer parti depuis une interface de programmation. Cependant, cette forte dépendance entre un logiciel et ses bibliothèques oblige les développeurs à reconsidérer leur rôle lorsque le logiciel évolue. Dans cette thèse, nous identifions plusieurs problématiques impliquant les bibliothèques tierces dans un contexte de maintenance logicielle. Plus particulièrement, une bibliothèque peut ne plus répondre aux besoins d’un logiciel et doit être remplacée par une nouvelle.Nous nommons cette opération une migration de bibliothèque.Nous soulevons dans ce contexte trois points qui caractérisent les difficultés rencontrées par les développeurs. Vers quelle bibliothèque migrer ? Comment appliquer la migration ? Avec l’aide de quels développeurs ? Cette thèse discute de solutions et apporte des contributions autour de ces problèmes. Nous présentons plusieurs approches et les évaluons lors de différents cas d’étude. L’analyse de l’évolution logicielle sera notre support de travail, dont la méthodologie est basée sur l’observation des changements de logiciels. Nous décrivons les limites actuelles de nos contribu-tions et ouvrons des perspectives futures pour enrichir l’état de l’art dans ce domaine / Software depend on third-party libraries to reduce development and maintenance costs. Developers have access to robust functionalities through an application programming interface designed by these libraries. However, due to the strong relationship with these libraries, developers have to reconsider their position when the software evolves. In this thesis, we identify several re-search problems involving these third-party libraries in a context of software maintenance. More specifically, a library may not satisfy the software new requirements and has to be replaced by anew one. We call this operation a library migration.We leverage three points that characterize the impediments met by developers in this situation.To which library should they migrate ? How to migrate their software ? Who can help them in this case ? This thesis suggests answers and exposes several contributions to these problems. We define three approaches that are evaluated through several case studies. To achieve this work, weuse a methodology based on software evolution analysis to observe and understand how software change. We describe numerous perspectives to overcome the current limitations of our solutions.

Dans les modèles à objets distinguant la notion de classe (ensemble d'individus) de celle d'instance (individu particulier), la classe peut jouer deux rôles fondamentalement différents. Les modèles qui mettent en œuvre des mécanismes de classification d'instances, présentent la classe comme une unité d'identification caractérisant les propriétés que doivent posséder toutes ses instances. Ces propriétés sont alors utilisées pour établir l'appartenance d'une instance à une classe. D'autres modèles utilisent la classe comme unité de construction, ou de gestion, d'instances. Ils laissent alors toutes libertés dans la description de la classe pour introduire des informations procédurales qui sont utilisées pour modifier ou compléter une instance qui lui a été explicitement rattachée. Notre travail consiste à mettre en place un mécanisme capable de trouver les différentes solutions que peut proposer une hiérarchie de classes à un problème de construction d'instance. Schématiquement, un tel problème se caractérise par la donnée d'une instance pour laquelle subsistent des possibilités de raffinement dans la hiérarchie de classes et dont la valeur de certains attributs reste inconnue. La solution proposée prend place dans un modèle à objets, appelé TROPES, défini pour accueillir un raisonnement classificatoire. La mise en place du mécanisme de construction d'instance par exploration d'une hiérarchie est assurée par un système, dit d'assistance hypothétique, couplé au système TROPES. Ce système d'assistance est chargé de produire et de gérer les hypothèses permettant de prolonger l'exploration d'une hiérarchie de classes au delà des limites atteintes par la classification d'instances. Les différentes combinaisons d'hypothèses pouvant ainsi être formées sont validées par TROPES sur des versions différentes de l'instance. Lorsque le mécanisme est appliqué à un objet composite, le partage de valeurs d'attributs entre composants et composite permet la propagation du processus de construction du composite vers les composants

Guide est un système d'exploitation expérimental reparti sur un réseau local. Les informations qu'il manipule sont structurées selon un modelé à objets. La description de l'un des composants de la machine virtuelle réalisant la gestion d'objets, a savoir la mémoire d'objets, est proposée. Sont présentés les choix de conception, sa réalisation et une analyse de l'expérience acquise. La mémoire d'objets est repartie et comporte deux niveaux: la mémoire virtuelle d'objets, qui constitue le support d'exécution des objets et la mémoire permanente d'objets, qui se charge de leur conservation

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<p>The need for change of direction in Software Engineering has been suggested in severalresources [Power of Models]. In recent years many organizations have focused on ModelDriven Engineering (MDE) as an approach to application design and implementation.Model Driven Architecture (MDA) was introduced by Object Management Group (OMG) in2001 in support of MDE. Models are the basic elements in MDE. The focus on MDE is onthe concept of “Everything is a model”. So far several languages, tools and platforms havebeen created for MDE.In particular, models can be developed in a distributed environment, thus once they mergetogether, conflicts and inconsistencies should be detected in a convenient way to bereconciled (automatically by software or manually by developers). This project is based onprevious works that define difference and conflict metamodels of a source model. In thisreport, we introduce the benefits of versioning systems in MDE framework. A conflictmetamodel that is generated from the input metamodel and the architecture for detectingconflicts are represented. The proposed approach is metamodel independent that meansconflict metalmodel is created for any input model which conforms to Kernel Meta MetaModel (KM3). The concept of used conflict model can be also changed regardless ofmodels. The extended idea for conflicts detection, the presented architecture for modelcode management and the tools that can detect conflicts of concurrent models can help toimprove MDE in model code management. For this report, some implementation in Eclipseplatform has been rendered while some future works are suggested.</p> / University of L'Aquila, Project group in Moedling with Alfonso Pierantonio

Aspect-oriented middleware is a promising technology for the realisation of dynamic reconfiguration in heterogeneous distributed systems. However, like other dynamic reconfiguration approaches, AO-middleware-based reconfiguration requires that the consistency of the system is maintained across reconfigurations. AO-middleware-based reconfiguration is an ongoing research topic and several consistency approaches have been proposed. However, most of these approaches tend to be targeted at specific contexts, whereas for distributed systems it is crucial to cover a wide range of operating conditions. In this paper we propose an approach that offers distributed, dynamic reconfiguration in a consistent manner, and features a flexible framework-based consistency management approach to cover a wide range of operating conditions. We evaluate our approach by investigating the configurability and transparency of our approach and also quantify the performance overheads of the associated consistency mechanisms.

In a variety of text document editing and processing applications, it is necessary to keep track of the revision history of text documents by recording changes and the metadata of those changes (e.g., user names and modification timestamps). The recent Web 2.0 document editing and processing applications, such as real-time collaborative note taking and wikis, require fine-grained shared access to collaborative text documents as well as efficient retrieval of metadata associated with different parts of collaborative text documents. Current revision control techniques only support coarse-grained shared access and are inefficient to retrieve metadata of changes at the sub-document granularity. In this dissertation, we design and implement partial persistent sequences (PPSs) to support real-time collaborations and manage metadata of changes at fine granularities for collaborative text document editing and processing applications. As a persistent data structure, PPSs have two important features. First, items in the data structure are never removed. We maintain necessary timestamp information to keep track of both inserted and deleted items and use the timestamp information to reconstruct the state of a document at any point in time. Second, PPSs create unique, persistent, and ordered identifiers for items of a document at fine granularities (e.g., a word or a sentence). As a result, we are able to support consistent and fine-grained shared access to collaborative text documents by detecting and resolving editing conflicts based on the revision history as well as to efficiently index and retrieve metadata associated with different parts of collaborative text documents. We demonstrate the capabilities of PPSs through two important problems in collaborative text document editing and processing applications: data consistency control and fine-grained document provenance management. The first problem studies how to detect and resolve editing conflicts in collaborative text document editing systems. We approach this problem in two steps. In the first step, we use PPSs to capture data dependencies between different editing operations and define a consistency model more suitable for real-time collaborative editing systems. In the second step, we extend our work to the entire spectrum of collaborations and adapt transactional techniques to build a flexible framework for the development of various collaborative editing systems. The generality of this framework is demonstrated by its capabilities to specify three different types of collaborations as exemplified in the systems of RCS, MediaWiki, and Google Docs respectively. We precisely specify the programming interfaces of this framework and describe a prototype implementation over Oracle Berkeley DB High Availability, a replicated database management engine. The second problem of fine-grained document provenance management studies how to efficiently index and retrieve fine-grained metadata for different parts of collaborative text documents. We use PPSs to design both disk-economic and computation-efficient techniques to index provenance data for millions of Wikipedia articles. Our approach is disk economic because we only save a few full versions of a document and only keep delta changes between those full versions. Our approach is also computation-efficient because we avoid the necessity of parsing the revision history of collaborative documents to retrieve fine-grained metadata. Compared to MediaWiki, the revision control system for Wikipedia, our system uses less than 10% of disk space and achieves at least an order of magnitude speed-up to retrieve fine-grained metadata for documents with thousands of revisions.

Denial-of-Service (DoS) attacks form a very important category of security threats that are possible in MIPv6 (Mobile Internet Protocol version 6). This thesis proposes a scheme for participants (Mobile Node, Home Agent, and Correspondent Node) in MIPv6 to recover from DoS attacks in the event of any of them being subjected to a DoS attack. We propose a threshold based scheme for participants in MIPv6 to detect presence of DoS attacks and to recover from DoS attacks in the event of any of them being subjected to a DoS attack. This is achieved using an infrastructure for MIPv6 that makes such a solution practical even in the absence of IPsec infrastructure. We propose a protocol that uses concepts like Cryptographically Generated Addresses (CGA), short-term IP addresses using a Lamport hash like mechanism and a hierarchy based trust management infrastructure for key distribution. However, reasoning about correctness of such protocols is not trivial. In addition, new solutions to mitigate attacks may need to be deployed in the network on a frequent basis as and when attacks are detected, as it is practically impossible to anticipate all attacks and provide solutions in advance. This makes it necessary to validate solutions in a timely manner before deployment in real network. However, threshold schemes needed in group protocols make analysis complex. Model checking threshold-based group protocols that employ cryptography have been not successful so far. The testing in a real network or a test bed also will not be feasible if faster and frequent deployment of DoS mitigation solutions is needed. Hence, there is a need for an approach that lies between automated/manual verification and an actual implementation. It is evident from existing literature that not many simulations for doing security analysis of MIP/MIPv6 have been done. This research is a step in that direction. We propose a simulation based approach for validation using a tool called FRAMOGR [40] that supports executable specification of group protocols that use cryptography. FRAMOGR allows one to specify attackers and track probability distributions of values or paths. This work deals with simulation of DoS attacks and their mitigation solutions for MIP in FRAMOGR. This makes validation of solutions possible without mandating a complete deployment of the protocol to detect vulnerabilities in a solution. This does away with the need for a formal theoretical verification of a DoS mitigation solution. In the course of this work, some DoS attacks and recovery mechanisms are simulated and validated using FRAMOGR. We obtained encouraging results for the performance of the detection scheme. We believe that infrastructure such as FRAMOGR would be required in future for validating new group based threshold protocols that are needed for making MIPv6 more robust.

Tyrime dalyvavo 18 - 69 metų amžiaus 92 tiriamieji, 63 moterys ir 29 vyrai. Darbe naudoti tiesioginis (akselerometrija) ir netiesioginis (IPAQ-LT trumposios versijos klausimynas) metodai, siekiant įvertinti tiriamųjų bendrą savaitės fizinį aktyvumą ir palyginti gautus duomenis tarpusavyje. Kiekvienas tyrimo dalyvis IPAQ-LT trumposios versijos anketą pildė baigęs fizinio aktyvumo (FA) vertinimą akselerometru (buvo prisimenamas FA praėjusios savaitės – pirmas anketų pildymo atvejis) ir kitą - po savaitės baigus FA vertinimą akselerometru (buvo prašoma ,,prisiminti“ FA vykusį už praėjusią savaitę - antras anketų pildymo atvejis). Pagal IPAQ-LT trumposios versijos pirmo ir antro anketos pildymo atvejų gautus bendrus savaitės fizinio aktyvumo duomenis, tarp pirmo ir antro anketos pildymo atvejų egzistuoja vidutinis koreliacinis ryšys (rho=0,531, p=0,01). Vertinant akselerometro pagalba gautus duomenis ir lyginant juos su anketų duomenimis (bendro savaitės fizinio aktyvumo pirmo ir antro anketos pildymo atvejų) tarp akselerometro nustatyto FA ir IPAQ-LT pirmo anketų pildymo atvejo egzistuoja silpnas koreliacinis ryšys (r=0,270, p=0,009), o tarp antro IPAQ-LT anketų pildymo atvejo – labai silpnas ryšys (r=0,057, p=0,591). Tyrimo metu gauti rezultatai leidžia teigti, kad dauguma tyrime dalyvavusių savanorių savo fizinį aktyvumą buvo linkę pervertinti. Tyrimo objektas - IPAQ-LT trumposios versijos klausimynas ir jo patikimumo bei pagrįstumo nustatymas. Darbo tikslas – nustatyti... [toliau žr. visą tekstą] / The study involved 92 18 - 69 year old subjects, 63 women and 29 men. In our work we used the direct (accelerometer) and indirect (IPAQ-LT short version of the questionnaire) methods to assess the total weekly physical activity and compare the findings with each other. Each study participant the first International physical activity questionnaire short Lithuanian version filled when completed physical activity estimation with accelerometer (physical activity was remembered of the last week - the first case of the questionnaires filling and another - after a week when physical activity estimation was completed with accelerometer (was asked „to remember“ physical activity that was done for the last week - the second case of the questionnaires filling). According to the IPAQ-LT short version the first and second questionnaire filling cases received the total weekly physical activity data between the first and second questionnaire filling cases exists a moderate correlation (rho=0,531, p=0,01). Evaluating the data of accelerometer and comparing them with the questionnaire data (the first and second guestionnaire filling cases of the total weekly physical activity) between the accelerometer and the the first guestionnaires filling case there is a small correlation (r=0,270, p=0,009), but between the second guestionnaires filling case - a very small (negligible) correliation (r=0,057, p=0,591). The study results suggest that the majority of volunteers in the study of their... [to full text]

Darbe atlikta teorinė gyvenimo kokybės sampratos ir lėtiniu inkstų nepakankamumu sergančių pacientų gyvenimo bruožų analizė.Iškelta hipotezė, kad dialize gydomi pacientai blogai vertina visas pagrindines gyvenimo kokybės sritis. Gyvenimo kokybės klausimynu ir interviu pokalbio metodais buvo atliktas tyrimas, kurio tikslas - ištirti dialize gydomų pacientų gyvenimo kokybę. Tyrimo duomenys apdoroti statistinių programų paketu SPSS Statistics 17.0, Microsoft Excel ir turinio (angl. content) analizės metodu. Tyrime dalyvavo 100 dialize gydomų pacientų, iš kurių 5 pacientai dalyvavo interviu pokalbyje. Empirinėje dalyje nagrinėjamas dialize gydomų pacientų pagrindinių gyvenimo sričių (fizinės sveikatos, psichologinės, socialinių santykių, aplinkos sričių) vertinimas ir gyvenimo kokybės ypatumai. / The work carried out in the theoretical concept of quality of life and chronic renal failure patients living traits analyzed.The hypothesis that dialysis patients bad the quality of life of all the key areas.The quality of life questionnaire and interview techniques interview was conducted with the aim - to investigate dialysis patients quality of life. The data processing of the statistical software package SPSS 17.0, Microsoft Excel, and text content analysis.The study included 100 dialysis patients, of which five patients participated in the interview conversation.In the empirical part of dialysis patients major life domains (physical health, psychological, social relationships, environment areas) Assessment of quality of life features.