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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.
21

Empirically-based self-diagnosis and repair of domain knowledge

Jones, Joshua K. 17 December 2009 (has links)
In this work, I view incremental experiential learning in intelligent software agents as progressive agent self-adaptation. When an agent produces an incorrect behavior, then it may reflect on, and thus diagnose and repair, the reasoning and knowledge that produced the incorrect behavior. In particular, I focus on the self-diagnosis and self-repair of an agent's domain knowledge. The implementation of systems with the capability to self-diagnose and self-repair involves building both reasoning processes capable of such learning and knowledge representations capable of supporting those reasoning processes. The core issue my dissertation addresses is: what kind of metaknowledge (knowledge about knowledge) may enable the agent to diagnose faults in its domain knowledge? In providing a solution to this issue, the central contribution of this research is a theory of the kind of metaknowledge that enables a system to reason about and adapt its conceptual knowledge. For this purpose, I propose a representation that explicitly encodes metaknowledge in the form of procedures called Empirical Verification Procedures (EVPs). In the proposed knowledge representation, an EVP is associated with each concept within the agent's domain knowledge. Each EVP explicitly semantically grounds the associated concept in the agent's perception, and can thus be used as a test to determine the validity of knowledge of that concept during diagnosis. I present the formal and empirical evaluation of a system, Augur, that makes use of EVP metaknowledge to adapt its own domain knowledge in the context of a particular subclass of classification problem that I call compositional classification, in which the overall classification task can be broken into a hierarchically organized set of subtasks. I hypothesize that EVP metaknowledge will enable a system to automatically adapt its knowledge in two ways: first, by adjusting the ways that inputs are categorized by a concept, in accordance with semantics fixed by an associated EVP; and second, by adjusting the semantics of concepts themselves when they fail to contribute appropriately to system goals. The latter adaptation is realized by altering the EVP associated with the concept in question. I further hypothesize that the semantic grounding of domain concepts in perception through the use of EVPs will increase the generalization power of a learner that operates over those concepts, and thus make learning more efficient. Beyond the support of these hypotheses, I also present results pertinent to the understanding of learning in compositional classification settings using structured knowledge representations.
22

An API for adaptive loop scheduling in shared address space architectures

Govindaswamy, Kirthilakshmi. January 2003 (has links) (PDF)
Thesis (M.S.)--Mississippi State University. Department of Computer Science and Engineering. / Title from title screen. Includes bibliographical references.
23

A Model-Based Approach to Engineer Self-Adaptive Systems with Guarantees / En modelbaserad metod för att utveckla självadaptiva system med garantier

Iftikhar, Muhammad Usman January 2017 (has links)
Modern software systems are increasingly characterized by uncertainties in the operating context and user requirements. These uncertainties are difficult to predict at design time. Achieving the quality goals of such systems depends on the ability of the software to deal with these uncertainties at runtime. A self-adaptive system employs a feedback loop to continuously monitor and adapt itself to achieve particular quality goals (i.e., adaptation goals) regardless of uncertainties. Current research applies formal techniques to provide guarantees for adaptation goals, typically using exhaustive verification techniques. Although these techniques offer strong guarantees for the goals, they suffer from well-known state explosion problem. In this thesis, we take a broader perspective and focus on two types of guarantees: (1) functional correctness of the feedback loop, and (2) guaranteeing the adaptation goals in an efficient manner. To that end, we present ActivFORMS (Active FORmal Models for Self-adaptation), a formally founded model-driven approach for engineering self-adaptive systems with guarantees. ActivFORMS achieves functional correctness by direct execution of formally verified models of the feedback loop using a reusable virtual machine. To efficiently provide guarantees for the adaptation goals with a required level of confidence, ActivFORMS applies statistical model checking at runtime. ActivFORMS supports on the fly changes of adaptation goals and updates of the verified feedback loop models that meet the changed goals. To demonstrate the applicability and effectiveness of the approach, we applied ActivFORMS in several domains: warehouse transportation, oceanic surveillance, tele assistance, and IoT building security monitoring. / Marie Curie CIG, FP7-PEOPLE-2011-CIG, Project ID: 303791
24

Engineering innovation (TRIZ based computer aided innovation)

Shahdad, Mir Abubakr January 2015 (has links)
This thesis describes the approach and results of the research to create a TRIZ based computer aided innovation tools (AEGIS and Design for Wow). This research has mainly been based around two tools created under this research: called AEGIS (Accelerated Evolutionary Graphics Interface System), and Design for Wow. Both of these tools are discussed in this thesis in detail, along with the test data, design methodology, test cases, and research. Design for Wow (http://www.designforwow.com) is an attempt to summarize the successful inventions/ designs from all over the world on a web portal which has multiple capabilities. These designs/innovations are then linked to the TRIZ Principles in order to determine whether innovative aspects of these successful innovations are fully covered by the forty TRIZ principles. In Design for Wow, a framework is created which is implemented through a review tool. The Design for Wow website includes this tool which has been used by researcher and the users of the site and reviewers to analyse the uploaded data in terms of strength of TRIZ Principles linked to them. AEGIS (Accelerated Evolutionary Graphics Interface System) is a software tool developed under this research aimed to help the graphic designers to make innovative graphic designs. Again it uses the forty TRIZ Principles as a set of guiding rules in the software. AEGIS creates graphic design prototypes according to the user input and uses TRIZ Principles framework as a guide to generate innovative graphic design samples. The AEGIS tool created is based on TRIZ Principles discussed in Chapter 3 (a subset of them). In AEGIS, the TRIZ Principles are used to create innovative graphic design effects. The literature review on innovative graphic design (in chapter 3) has been analysed for links with TRIZ Principles and then the DNA of AEGIS has been built on the basis of this study. Results from various surveys/ questionnaires indicated were used to collect the innovative graphic design samples and then TRIZ was mapped to it (see section 3.2). The TRIZ effects were mapped to the basic graphic design elements and the anatomy of the graphic design letters was studied to analyse the TRIZ effects in the collected samples. This study was used to build the TRIZ based AEGIS tool. Hence, AEGIS tool applies the innovative effects using TRIZ to basic graphic design elements (as described in section 3.3). the working of AEGIS is designed based on Genetic Algorithms coded specifically to implement TRIZ Principles specialized for Graphic Design, chapter 4 discusses the process followed to apply TRIZ Principles to graphic design and coding them using Genetic Algorithms, hence resulting in AEGIS tool. Similarly, in Design for Wow, the content uploaded has been analysed for its link with TRIZ Principles (see section 3.1 for TRIZ Principles). The tool created in Design for Wow is based on the framework of analysing the TRIZ links in the uploaded content. The ‘Wow’ concept discussed in the section 5.1 and 5.2 is the basis of the concept of Design for Wow website, whereby the users upload the content they classify as ‘Wow’. This content then is further analysed for the ‘Wow factor’ and then mapped to TRIZ Principles as TRIZ tagging methodology is framed (section 5.5). From the results of the research, it appears that the TRIZ Principles are a comprehensive set of innovation basic building blocks. Some surveys suggest that amongst other tools, TRIZ Principles were the first choice and used most .They have thus the potential of being used in other innovation domains, to help in their analysis, understanding and potential development.
25

Uma camada de adaptação para transmissão de mídias digitais. / An adaptation layer for multimedia transmission.

Kulesza, Raoni 21 July 2006 (has links)
A convergência da Internet com outras redes (telefonia móvel e televisão digital), o surgimento da computação ubíqua e crescente demanda pela computação autônoma, tem favorecido a existência de um ambiente constantemente modificado e altamente dinâmico, caracterizado pelo tratamento e transporte de conteúdo multimídia, heterogeneidade nos recursos, tecnologias de redes e dispositivos de acesso. Este cenário tem exigido a existência de sistemas adaptativos, ou seja, que tenham a capacidade de se adaptar dinamicamente em resposta a mudanças no contexto em que estão inseridos. O projeto de software de sistemas adaptativos que visem atender de forma satisfatória evolução e mudança neste novo ambiente heterogêneo da Internet tem particular relevância e complexidade. Um dos principais desafios é realizar a implementação de comportamentos adaptativos sem entrelaçamento com outras funcionalidades da aplicação, que podem levar a dificuldade de legibilidade e prejudicar a manutenção do código. Este trabalho procura abordar este tema empregando programação orientada a aspectos na especificação e implementação de uma camada de adaptação que atua sobre aplicações multimídia em rede utilizando abordagens de adaptação baseados em servidor. Em particular, através do uso da linguagem AspectJ, é mostrado como promovemos a separação do interesse de adaptabilidade de forma modular para permitir que a camada de adaptação realize configuração estática e dinâmica de processos de transmissão de fluxos multimídia a partir de mecanismos de monitoração do seu ambiente de operação. / The convergence of the Internet with other networks (e.g. Mobile Telecom and Digital Television Networks), the ubiquitous computing raising and the increasing demand on the autonomic computing has favored the existence of a constantly modified and highly dynamic environment. It is characterized by the treatment and transport of multimedia content and resources, network technologies and access devices heterogeneity. This scenario has demanded the existence of adaptive systems, which has the capacity to dynamically adapt based on the context where they are inserted. The software design for adaptive systems, which aim to deal on a satisfactory way the evolution and changes in this new heterogeneous Internet environment, has particular relevance and complexity. One of the main challenges is performing the development of adaptive behaviors without tangled and scattered code along other application functionalities, which could result in code legibly problems, affecting its maintenance. The main purpose of this work is the specification and development of an adaptation layer working in multimedia networked application and using server based adaptation approach, making use of aspect oriented programming. Specifically, through the adoption of the AspectJ language it was showed how the adaptability concern was well modularized by enabling the adaptation layer to perform static and dynamic configuration of the multimedia chains through the monitoring of its operational environment.
26

Uma camada de adaptação para transmissão de mídias digitais. / An adaptation layer for multimedia transmission.

Raoni Kulesza 21 July 2006 (has links)
A convergência da Internet com outras redes (telefonia móvel e televisão digital), o surgimento da computação ubíqua e crescente demanda pela computação autônoma, tem favorecido a existência de um ambiente constantemente modificado e altamente dinâmico, caracterizado pelo tratamento e transporte de conteúdo multimídia, heterogeneidade nos recursos, tecnologias de redes e dispositivos de acesso. Este cenário tem exigido a existência de sistemas adaptativos, ou seja, que tenham a capacidade de se adaptar dinamicamente em resposta a mudanças no contexto em que estão inseridos. O projeto de software de sistemas adaptativos que visem atender de forma satisfatória evolução e mudança neste novo ambiente heterogêneo da Internet tem particular relevância e complexidade. Um dos principais desafios é realizar a implementação de comportamentos adaptativos sem entrelaçamento com outras funcionalidades da aplicação, que podem levar a dificuldade de legibilidade e prejudicar a manutenção do código. Este trabalho procura abordar este tema empregando programação orientada a aspectos na especificação e implementação de uma camada de adaptação que atua sobre aplicações multimídia em rede utilizando abordagens de adaptação baseados em servidor. Em particular, através do uso da linguagem AspectJ, é mostrado como promovemos a separação do interesse de adaptabilidade de forma modular para permitir que a camada de adaptação realize configuração estática e dinâmica de processos de transmissão de fluxos multimídia a partir de mecanismos de monitoração do seu ambiente de operação. / The convergence of the Internet with other networks (e.g. Mobile Telecom and Digital Television Networks), the ubiquitous computing raising and the increasing demand on the autonomic computing has favored the existence of a constantly modified and highly dynamic environment. It is characterized by the treatment and transport of multimedia content and resources, network technologies and access devices heterogeneity. This scenario has demanded the existence of adaptive systems, which has the capacity to dynamically adapt based on the context where they are inserted. The software design for adaptive systems, which aim to deal on a satisfactory way the evolution and changes in this new heterogeneous Internet environment, has particular relevance and complexity. One of the main challenges is performing the development of adaptive behaviors without tangled and scattered code along other application functionalities, which could result in code legibly problems, affecting its maintenance. The main purpose of this work is the specification and development of an adaptation layer working in multimedia networked application and using server based adaptation approach, making use of aspect oriented programming. Specifically, through the adoption of the AspectJ language it was showed how the adaptability concern was well modularized by enabling the adaptation layer to perform static and dynamic configuration of the multimedia chains through the monitoring of its operational environment.
27

Model-driven engineering of adaptation engines for self-adaptive software : executable runtime megamodels

Vogel, Thomas, Giese, Holger January 2013 (has links)
The development of self-adaptive software requires the engineering of an adaptation engine that controls and adapts the underlying adaptable software by means of feedback loops. The adaptation engine often describes the adaptation by using runtime models representing relevant aspects of the adaptable software and particular activities such as analysis and planning that operate on these runtime models. To systematically address the interplay between runtime models and adaptation activities in adaptation engines, runtime megamodels have been proposed for self-adaptive software. A runtime megamodel is a specific runtime model whose elements are runtime models and adaptation activities. Thus, a megamodel captures the interplay between multiple models and between models and activities as well as the activation of the activities. In this article, we go one step further and present a modeling language for ExecUtable RuntimE MegAmodels (EUREMA) that considerably eases the development of adaptation engines by following a model-driven engineering approach. We provide a domain-specific modeling language and a runtime interpreter for adaptation engines, in particular for feedback loops. Megamodels are kept explicit and alive at runtime and by interpreting them, they are directly executed to run feedback loops. Additionally, they can be dynamically adjusted to adapt feedback loops. Thus, EUREMA supports development by making feedback loops, their runtime models, and adaptation activities explicit at a higher level of abstraction. Moreover, it enables complex solutions where multiple feedback loops interact or even operate on top of each other. Finally, it leverages the co-existence of self-adaptation and off-line adaptation for evolution. / Die Entwicklung selbst-adaptiver Software erfordert die Konstruktion einer sogenannten "Adaptation Engine", die mittels Feedbackschleifen die unterliegende Software steuert und anpasst. Die Anpassung selbst wird häufig mittels Laufzeitmodellen, die die laufende Software repräsentieren, und Aktivitäten wie beispielsweise Analyse und Planung, die diese Laufzeitmodelle nutzen, beschrieben. Um das Zusammenspiel zwischen Laufzeitmodellen und Aktivitäten systematisch zu erfassen, wurden Megamodelle zur Laufzeit für selbst-adaptive Software vorgeschlagen. Ein Megamodell zur Laufzeit ist ein spezielles Laufzeitmodell, dessen Elemente Aktivitäten und andere Laufzeitmodelle sind. Folglich erfasst ein Megamodell das Zusammenspiel zwischen verschiedenen Laufzeitmodellen und zwischen Aktivitäten und Laufzeitmodellen als auch die Aktivierung und Ausführung der Aktivitäten. Darauf aufbauend präsentieren wir in diesem Artikel eine Modellierungssprache für ausführbare Megamodelle zur Laufzeit, EUREMA genannt, die aufgrund eines modellgetriebenen Ansatzes die Entwicklung selbst-adaptiver Software erleichtert. Der Ansatz umfasst eine domänen-spezifische Modellierungssprache und einen Laufzeit-Interpreter für Adaptation Engines, insbesondere für Feedbackschleifen. EUREMA Megamodelle werden über die Spezifikationsphase hinaus explizit zur Laufzeit genutzt, um mittels Interpreter Feedbackschleifen direkt auszuführen. Zusätzlich können Megamodelle zur Laufzeit dynamisch geändert werden, um Feedbackschleifen anzupassen. Daher unterstützt EUREMA die Entwicklung selbst-adaptiver Software durch die explizite Spezifikation von Feedbackschleifen, der verwendeten Laufzeitmodelle, und Adaptionsaktivitäten auf einer höheren Abstraktionsebene. Darüber hinaus ermöglicht EUREMA komplexe Lösungskonzepte, die mehrere Feedbackschleifen und deren Interaktion wie auch die hierarchische Komposition von Feedbackschleifen umfassen. Dies unterstützt schließlich das integrierte Zusammenspiel von Selbst-Adaption und Wartung für die Evolution der Software.
28

Issues in Specifying Requirements for Adaptive Software Systems

Peng, Qian January 2009 (has links)
<p>This thesis emphasizes on surveying the state-of-the-art in software requirements specification with a focus on, autonomic, self-adapting software systems. Since various requirements are brought forward accord with environments, modeling requirements for adaptive software systems may be changed at run-time. Nowadays, Keep All Objectives Satisfied (KAOS) is an effective method to build goal model. Various manipulations, such as change, remove, active and de-active goals, appear new goals, could mediate conflicts among goals in adaptive software system. At specification time, specifications of event sequences to be monitored are generated from requirements specification.</p>
29

Context management and self-adaptivity for situation-aware smart software systems

Villegas Machado, Norha Milena 25 February 2013 (has links)
Our society is increasingly demanding situation-aware smarter software (SASS) systems, whose goals change over time and depend on context situations. A system with such properties must sense their dynamic environment and respond to changes quickly, accurately, and reliably, that is, to be context-aware and self-adaptive. The problem addressed in this dissertation is the dynamic management of context information, with the goal of improving the relevance of SASS systems' context-aware capabilities with respect to changes in their requirements and execution environment. Therefore, this dissertation focuses on the investigation of dynamic context management and self-adaptivity to: (i) improve context-awareness and exploit context information to enhance quality of user experience in SASS systems, and (ii) improve the dynamic capabilities of self-adaptivity in SASS systems. Context-awareness and self-adaptivity pose signi cant challenges for the engineering of SASS systems. Regarding context-awareness, the rst challenge addressed in this dissertation is the impossibility of fully specifying environmental entities and the corresponding monitoring requirements at design-time. The second challenge arises from the continuous evolution of monitoring requirements due to changes in the system caused by self-adaptation. As a result, context monitoring strategies must be modeled and managed in such a way that they support the addition and deletion of context types and monitoring conditions at runtime. For this, the user must be integrated into the dynamic context management process. Concerning self-adaptivity, the third challenge is to control the dynamicity of adaptation goals, adaptation mechanisms, and monitoring infrastructures, and the way they a ect each other in the adaptation process. This is to preserve the eff ectiveness of context monitoring requirements and thus self-adaptation. The fourth challenge, related also to self-adaptivity,concerns the assessment of adaptation mechanisms at runtime to prevent undesirable system states as a result of self-adaptation. Given these challenges, to improve context-awareness we made three contributions. First, we proposed the personal context sphere concept to empower users to control the life cycle of personal context information in user-centric SASS systems. Second, we proposed the SmarterContext ontology to model context information and its monitoring requirements supporting changes in these models at runtime. Third, we proposed an effi cient context processing engine to discover implicit contextual facts from context information speci fied in changing context models. To improve self-adaptivity we made three contributions. First, we proposed a framework for the identi cation of adaptation properties and goals, which is useful to evaluate self-adaptivity and to derive monitoring requirements mapped to adaptation goals. Second, we proposed a reference model for designing highly dynamic self-adaptive systems, for which the continuous pertinence between monitoring mechanisms and both changing system goals and context situations is a major concern. Third, we proposed a model with explicit validation and veri cation (V&V) tasks for self-adaptive software, where dynamic context monitoring plays a major role. The seventh contribution of this dissertation, the implementation of Smarter-Context infrastructure, addresses both context-awareness and self-adaptivity. To evaluate our contributions, qualitatively and quantitatively, we conducted several comprehensive literature reviews, a case study on user-centric situation-aware online shopping, and a case study on dynamic governance of service-oriented applications. / Graduate
30

Issues in Specifying Requirements for Adaptive Software Systems

Peng, Qian January 2009 (has links)
This thesis emphasizes on surveying the state-of-the-art in software requirements specification with a focus on, autonomic, self-adapting software systems. Since various requirements are brought forward accord with environments, modeling requirements for adaptive software systems may be changed at run-time. Nowadays, Keep All Objectives Satisfied (KAOS) is an effective method to build goal model. Various manipulations, such as change, remove, active and de-active goals, appear new goals, could mediate conflicts among goals in adaptive software system. At specification time, specifications of event sequences to be monitored are generated from requirements specification.

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