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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.
601

Elicitación y especificación de requerimientos no funcionales en aplicaciones web

Rojo, Silvana del Valle 20 February 2014 (has links)
Este trabajo de tesis presenta lineamientos específicos para la aplicación de Ingeniería de Requerimientos Web al tratamiento de los RNF. Presenta procesos de Elicitación y Especificación de RNF Web y ofrece las plantillas diseñadas particularmente para la captura y especificación de los RNF en los procesos definidos. Si bien actualmente la Ingeniería de Requerimientos proporciona numerosas técnicas y herramientas para identificar, describir, validar y gestionar requerimientos, estos no son aplicados muy a menudo, en el desarrollo de aplicaciones Web. La madurez del proceso de ingeniería de requerimientos parece ser insuficiente, esa insuficiencia demanda nuevos enfoques o evolución de los actuales para el tratamiento adecuado de los RNF. Los RNF de los sistemas software no son un todo homogéneo, hay falta de consenso para responder a los interrogantes: ¿Qué son? ¿Cómo se clasifican dentro del contexto de desarrollo de software? y ¿Cómo se clasifican en el desarrollo de aplicaciones Web? Este trabajo parte de una revisión del estado de arte de los conceptos de RNF en la literatura de la Ingeniería de Requerimientos y establece como bases conceptuales que los RNF son requerimientos de calidad y son restricciones. Luego ofrece un análisis comparativo de seis enfoques existentes de desarrollo de aplicaciones Web para estudiar qué tratamiento aplican a los RNF, en el cual se pudo determinar que las metodologías de aplicaciones Web estudiadas: Contemplan los RNF, aunque se carece de consenso en su significado. No disponen de técnicas específicas para la elicitación de RNF, ni lineamientos uniformes para la especificación y la validación. No brindan técnicas que soporten el tratamiento de los RNF a lo largo del ciclo de vida. Hay carencia de consenso para establecer en qué fase del ciclo de vida de desarrollo se identifican los RNF. Hay RNF que no son identificados durante la fase de relevamiento y análisis. A partir de este análisis y dada la importancia de los RNF, se proponen procesos para la elicitación y especificación de los RNF Web (de calidad y restricciones), se describen las plantillas propuestas que dan soporte a los procesos y finalmente se presenta la validación de los conceptos y técnicas propuestos mediante un caso de estudio en un proyecto real. / This thesis introduces specifics guidelines to apply Web Requirements Engineering to the treatment of Non-Functional Requirements. It introduces the process of Elicitation and Specification for Web Non-Functional Requirements and offers spreadsheets designed to capture and specify Non-Functional Requirements in the defined processes. While at present Requirement Engineering has numerous techniques and tools to identify, describe, validate and manage requirements, these are not frequently applied in the development of Web applications. The maturity of the Requirements Engineering process seems insufficient; this insufficiency demands new approaches or the evolution of current process to the correct treatment of Non-Functional Requirements. Non-Functional Requirements of software systems are not homogenous; there is a lack of consensus to answer the following questions: What are Non-Functional Requirements? How they are classified within the context of software development? and How the Non-Functional Requirements are classified within the development of web software application? This thesis starts with a revision of the state of art of the concept of Non-Functional Requirements in Requirements Engineering literature and establishes as conceptual foundations that Non-Functional Requirements are quality requirements and restrictions. Then, there is a comparative analysis of six different existing approaches in Web application development to study what treatment applies to Non-Functional Requirements, in which methodologies of the Web applications studied: Non-Functional Requirements are considered, but there is no consensus in their meaning. There are neither specifics techniques for elicitation of Non-Functional Requirements nor uniform guidelines for the specification and validation. There are no techniques supporting the treatment of the Non-Functional Requirements along the lifetime cycle. There is a lack of consensus to establish within which phase of development lifetime cycle Non-Functional Requirements are identified. There are Non-Functional Requirements that are not indentified during requirement capture and analysis phases. After this analysis and the give importance of the Non-Functional Requirements, a process for the elicitation and specification of the Web Non-Functional Requirements (quality and restrictions) is proposed, exposed spreadsheets are described to support processes and finally, validations of the concepts and techniques are introduced applied to a real project.
602

Intrusion detection techniques in wireless local area networks

Gill, Rupinder S. January 2009 (has links)
This research investigates wireless intrusion detection techniques for detecting attacks on IEEE 802.11i Robust Secure Networks (RSNs). Despite using a variety of comprehensive preventative security measures, the RSNs remain vulnerable to a number of attacks. Failure of preventative measures to address all RSN vulnerabilities dictates the need for a comprehensive monitoring capability to detect all attacks on RSNs and also to proactively address potential security vulnerabilities by detecting security policy violations in the WLAN. This research proposes novel wireless intrusion detection techniques to address these monitoring requirements and also studies correlation of the generated alarms across wireless intrusion detection system (WIDS) sensors and the detection techniques themselves for greater reliability and robustness. The specific outcomes of this research are: A comprehensive review of the outstanding vulnerabilities and attacks in IEEE 802.11i RSNs. A comprehensive review of the wireless intrusion detection techniques currently available for detecting attacks on RSNs. Identification of the drawbacks and limitations of the currently available wireless intrusion detection techniques in detecting attacks on RSNs. Development of three novel wireless intrusion detection techniques for detecting RSN attacks and security policy violations in RSNs. Development of algorithms for each novel intrusion detection technique to correlate alarms across distributed sensors of a WIDS. Development of an algorithm for automatic attack scenario detection using cross detection technique correlation. Development of an algorithm to automatically assign priority to the detected attack scenario using cross detection technique correlation.
603

Design of a Test Generation Methodology for ARTIS using Model-Checking with a Generic Modelling Approach

Vernekar, Ganesh Kamalakar 22 January 2016 (has links) (PDF)
In the recent trends, automated systems are increasingly seen to be embedded in human life with the increase of human dependence on software to perform safetycritical tasks like airbag deployment in automobiles to real-time mission planning in UAVs (Unmanned Aircraft Vehicles). The safety-critical nature of the aerospace domain demands for a software without any errors to perform these tasks. Therefore the field of computer science needs to address these challenges by providing necessary formalisms, techniques, and tools that will ensure the correctness of systems despite their complexity. DO-178C/EC-12C is a standard that governs the certification of software for airborne systems in commercial aircraft. The additional supplement DO- 333 enables us to use the formal methods in our technique of verifying the autonomous behaviour of UAV’s. The Mission Manager system is primarily responsible for the execution of behaviour sequence in online and offline mission planning of UAV. This work presents the process of software verification by making use of formal modelling using model checking of the Mission Manager component of ARTIS (Autonomous Rotorcraft Testbed for Intelligent Systems) UAV by gaining advantages from a generic modelling approach. The main idea is to make use of the designed generic models into specific cases like ARTIS in our case. The generic models are designed using the ALFU(R)S (Autonomy Levels For Unmanned Rotorcraft System) framework that delineates the commonalities of several UAVs considered around the world which also includes the ARTIS UAV. Furthermore this work walks through every process involved in model checking like requirements extraction and documentation using a template based method, requirements specification using the temporal logics like LTL and CTL, developing a formal model using NuSMV as a model checking tool to analyze the requirements against the model for the Mission Manager component of MiPlEx (Mission Planning and Execution). Additionally as a validation approach, test sequences are generated by using trap properties or negation properties. This aids for a test generation approach by harnessing counterexample generating capabilities of the NuSMV Model Checker.
604

Towards a comparative evaluation of text-based specification formalisms and diagrammatic notations

Moremedi, Kobamelo 19 January 2017 (has links)
Specification plays a vital role in software engineering to facilitate the development of highly dependable software. The importance of specification in software development is to serve, amongst others, as a communication tool for stakeholders in the software project. The specification also adds to the understanding of operations, and describes the properties of a system. Various techniques may be used for specification work. Z is a formal specification language that is based on a strongly-typed fragment of Zermelo-Fraenkel set theory and first-order logic to provide for precise and unambiguous specifications. Z uses mathematical notation to build abstract data, which is necessary for a specification. The role of abstraction is to describe what the system does without prescribing how it should be done. Diagrams, on the other hand, have also been used in various areas, and in software engineering they could be used to add a visual component to software specifications. It is plausible that diagrams may also be used to reason in a semi-formal way about the properties of a specification. Many diagrammatic languages are based on contours and set theory. Examples of these languages are Euler-, Spider-, Venn- and Pierce diagrams. Euler diagrams form the foundation of most diagrams that are based on closed curves. Diagrams, on the other hand, have also been used in various areas, and in software engineering they could be used to add a visual component to software specifications. It is plausible that diagrams may also be used to reason in a semi-formal way about the properties of a specification. Many diagrammatic languages are based on contours and set theory. Examples of these languages are Euler-, Spider-, Venn- and Pierce diagrams. Euler diagrams form the foundation of most diagrams that are based on closed curves. The purpose of this research is to demonstrate the extent to which diagrams can be used to represent a Z specification. A case study is used to transform the specification modelled with Z language into a diagrammatic specification. Euler, spider, Venn and Pierce diagrams are combined for this purpose, to form one diagrammatic notation that is used to transform a Z specification / School of Computing / M. Sc. (Information Systems)
605

Uma proposta de modelagem conceitual de sistemas dirigida por comportamento / A proposal of behavior-driven systems conceptual modeling

Bustos Reinoso, Guillermo January 1996 (has links)
A Modelagem Orientada a Objetos (MOO) é o processo de construção de modelos de sistemas através da identificação e definição de um conjunto de objetos relacionados, que comportam-se e colaboram entre si conforme os requisitos estabelecidos para o sistema. Esta definição inclui os três aspectos ortogonais, ou dimensões, deste tipo de modelagem: a dimensão estrutural dos objetos, a dimensão dinâmica do comportamento e a dimensão funcional dos requisitos. Conforme a importância relativa dada a cada uma destas dimensões, podem ser definidas três estratégias possíveis para conduzir a MOO. Estas estratégias são as dirigidas por dados, por comportamento e por processos. A estratégia dirigida por processos já esta superada. Atualmente, a estratégia dirigida por dados domina na maioria das técnicas de MOO. A estratégia dirigida por comportamento propõe que a estrutura dos objetos em um sistema pode ser determinada a partir do comportamento externo e interno que o sistema deve apresentar. Esta idéia é interessante, porque permite introduzir tardiamente o encapsulamento na MOO. Conforme é argumentado neste trabalho, as vantagens atribuídas a orientação a objetos são de implementação, isto é, a decisão de orientar ou não a objetos é, na realidade, uma decisão de design. Ao introduzir o encapsulamento na modelagem inicial do sistema, ganha-se o benefício da continuidade estrutural ao custo de colocar a MOO mais perto do design. Neste contexto, este trabalho apresenta um processo de modelagem conceitual de sistemas do ponto de vista comportamental que introduz tardiamente o encapsulamento da orientação a objetos como primeiro passo de design. Em outras palavras, é proposta uma técnica de modelagem sob uma estratégia dirigida por comportamento (privilegiando, assim, o aspecto dinâmico dos sistemas) com o suficiente poder de expressão para, ao mesmo tempo, permitir a modelagem de sistemas de informação no nível conceitual e derivar dos modelos dinâmicos obtidos uma representação estrutural orientada a objetos. 0 sistema, na concepção desta proposta, é composto por um conjunto de processos concorrentes, cada um dos quais recebe um estimulo do ambiente, realiza um tratamento especifico sobre ele e gera para o ambiente uma resposta. Os estímulos externos são decompostos em conjuntos de eventos concorrentes tratados no interior do processo. As ações realizadas no interior do mesmo são compostas nas respostas geradas para o exterior. Os processos são modelados comportamentalmente, utilizando o formalismo proposto High-Level Statecharts (HLS). HLS é uma extensão dos statecharts de Harel. As principais extensões propostas são a introdução de estados "parametrizados" usando variáveis e a representação genérica de conjuntos de estados concorrentes e exclusivos. 0 modelo de processos e desintegrado em unidades de comportamento que tratam das mesmas variáveis. Estas unidades são integradas em um modelo de ciclos de vida para estas variáveis. Finalmente, apos a aplicação da técnica de modelagem conceitual, e obtido um modelo estrutural orientado a objetos. Este modelo e derivado utilizando unicamente informações contidas nos modelos dinâmicos gerados no processo da técnica proposta. No modelo estrutural são identificadas classes, objetos, atributos, associações estáticas, hierarquias de herança e operações. Todo o processo e exemplificado utilizando o problema padrão de preparação de congressos da IFIP. / Object-Oriented Modeling (OOM) is the process of construction of systems models, through an identification and definition of a set of relating objects. These objects have a collaborative behavior according to the system requirements previously defined. This definition includes three modeling aspects or dimensions: object structural dimension, behavior dynamic dimension and requirements functional dimension. Depending on a relative importance of each dimension, three possible strategies to drive OOM are defined. The strategies are: data-driven, behavior-driven and process-driven. Process-driven strategy is obsolete. Nowadays, data-driven is the dominant strategy in the world of OOM techniques. Behavior-driven strategy suggests both internal and external system behaviors define its object structure. This idea is attractive because it allows a late encapsulation in the OOM. As explained in this work, the main advantage to use object-orientation is for implementation. So, to object-orient or not to object-orient is a design decision. If encapsulation is introduced in the very beginning of systems modeling, the structural continuity is achieved at the cost of pulling OOM closer to design. In this context, the work presents a process of systems conceptual modeling using a behavioral point of view. This process introduces object-oriented encapsulation lately as a first step in the design phase. In other words, this work is a proposal of a modeling technique under a behavior-driven strategy (focusing the dynamic aspect of the systems) with enough expression power to model information systems at conceptual level and, at the same time, to derive of an object-oriented structural representation from the dynamic models. As conceived in the proposal, a system is composed by a set of concurrent processes. Each process receives a stimuli from the environment, makes a specific treatment on it and generates a response to the environment. The external stimuli is decomposed into a set of concurrent events which are internally handled by the process. Actions internally performed by the process are composed into a response which is sent outside the process. Processes are behaviorally modeled using a proposed formalism called High-Level Statecharts (HLS). HLS is a extension of Harel's statecharts. The main extensions proposed are parameterized states using variables and generic representation of concurrent and exclusive sets of states. Process model is disintegrated into behavior units handling the same variables. The units are integrated into a life cycle model for these variables. Finally, after the modeling technique has been applied, an object-oriented structural model is obtained. This model is derived exclusively using information from the dynamic models constructed during the modeling process. Classes, objects, attributes, static associations, inheritance hierarchies and operations in the structural model are identified. Examples used in all the modeling process are taken from the standard problem of IFIP conference.
606

The validation of a test battery for the selection of call centre operators in a communications company

Nicholls, Michelle Lee 11 1900 (has links)
The purpose of the research was to determine whether personality and measures of ability would significantly predict job performance of call centre operators in a South African communications company. The Customer Contact Styles Questionnaire (CCSQ7.2), the Basic Checking (CP7.1) ability test and the Audio Checking (CP8.1) ability test were completed by operators as the predictors. Supervisors completed the Customer Contact Competency Inventory (CCCI) for 140 operators as a measure of job performance. Performance statistics were obtained for the sample as additional criterion data. Correlations and multiple regression analysis revealed statistically significant small to moderate correlations between the criteria and the predictors. The research was conducted from a concurrent validity perspective. Further research from a predictive validity perspective is suggested in order to substantiate the findings and to improve the generalisability thereof. / Industrial and Organisational Psychology / M.A. (Industrial Psychology)
607

Structural equation modelling

Mohanlal, Pramod 06 1900 (has links)
Over the past two decades there has been an upsurge in interest in structural equation modelling (SEM). Applications abound in the social sciences and econometrics, but the use of this multivariate technique is not so common in public health research. This dissertation discusses the methodology, the criticisms and practical problems of SEM. We examine actual applications of SEM in public health research. Comparisons are made between multiple regression and SEM and between factor analysis and SEM. A complex model investigating the utilization of antenatal care services (ANC) by migrant women in Belgium is analysed using SEM. The dissertation concludes with a discussion of the results found and on the use of SEM in public health research. Structural equation modelling is recommended as a tool for public health researchers with a warning against using the technique too casually. / Mathematical Sciences / M. Sc. (Statistics)
608

'n Ondersoek na die rol van werkontleding in die uitvoering van funksionele personeelbedrywighede met verwysing na die Stadsraad van Lichtenburg

Muller, Catherina Elizabeth 11 1900 (has links)
Text in Afrikaans / Werkontleding word onderneem om die onderskeie funksies wat in 'n instelling uitgevoer word, te ontleed en te groepeer as pligte van individuele betrekkings wat in die proses ge1dentifiseer word. Inligting wat op grond van werkontleding verkry is, kan daartoe bydra dat die uitvoering van personeelfunksies doeltreffend en effektief geskied. 'n Li teratuurstudie en empiriese narvorsing is in hierdie·studie onderneem om te bepaal wat die rol van werkontleding in die ui tvoering van funksionele personeelbedrywighede in die Stadsraad van Lichtenburg is. Empiriese navorsing is onderneem in al die Departemente van die Stadsraad van Lichtenburg. Ten einde die doel van die studie te verwesenlik is vier navorsingsvrae gestel. Deur middel van vraelyste wat aan die teikengroep gestuur is, is data oor die navorsingsvrae ingesamel. Die empiriese studie het daarop gedui dat inligting verkry op grond van werkontleding wel kan bydra tot die effektiewe uitvoering van funksionele personeelbedrywighede. Dies studie het egter ui tgewys dat nie alle leidinggewende amptenare bewus is dat die inligting op grond van werkontleding verkry,. die uitvoering van hul personeelfunksies kan vergemaklik nie. / respective functions performed in an institution, as duties of individual jobs identified in the process. Information gathered on the basis of the job analysis, can contribute to the fact that the performing of personnel functions transpires efficiently and effectively. A literature study as well as empiricial research were undertaken in this study to determine ' what the role of job analyses is in the performing of functional personnel activities in the City Council of Lichtenburg. .on the basis of job analysis can definitely contribute to the effective performing of functional personnel activities. The study indicated however, that not all leadinq officials were aware that information gathered on the basis of job analysis, could expedite the performing of their personnel functions. / Public Administration and Management / M.Admin. (Public Administration)
609

Biblistika na českých vysokých školách od roku 1989 (instituce, osoby, díla) / Bible studies on Czech universities since 1989 (the institution, personalities, research work)

DOHNALOVÁ, Helena January 2014 (has links)
The main part of the thesis is a research focused on describing research activities at Czech universities since 1989 to the present time, i.e. until the end of 2013. The thesis describes the work and publications of all personalities who participated in the research within the field of Bible Studies.
610

Uma proposta de modelagem conceitual de sistemas dirigida por comportamento / A proposal of behavior-driven systems conceptual modeling

Bustos Reinoso, Guillermo January 1996 (has links)
A Modelagem Orientada a Objetos (MOO) é o processo de construção de modelos de sistemas através da identificação e definição de um conjunto de objetos relacionados, que comportam-se e colaboram entre si conforme os requisitos estabelecidos para o sistema. Esta definição inclui os três aspectos ortogonais, ou dimensões, deste tipo de modelagem: a dimensão estrutural dos objetos, a dimensão dinâmica do comportamento e a dimensão funcional dos requisitos. Conforme a importância relativa dada a cada uma destas dimensões, podem ser definidas três estratégias possíveis para conduzir a MOO. Estas estratégias são as dirigidas por dados, por comportamento e por processos. A estratégia dirigida por processos já esta superada. Atualmente, a estratégia dirigida por dados domina na maioria das técnicas de MOO. A estratégia dirigida por comportamento propõe que a estrutura dos objetos em um sistema pode ser determinada a partir do comportamento externo e interno que o sistema deve apresentar. Esta idéia é interessante, porque permite introduzir tardiamente o encapsulamento na MOO. Conforme é argumentado neste trabalho, as vantagens atribuídas a orientação a objetos são de implementação, isto é, a decisão de orientar ou não a objetos é, na realidade, uma decisão de design. Ao introduzir o encapsulamento na modelagem inicial do sistema, ganha-se o benefício da continuidade estrutural ao custo de colocar a MOO mais perto do design. Neste contexto, este trabalho apresenta um processo de modelagem conceitual de sistemas do ponto de vista comportamental que introduz tardiamente o encapsulamento da orientação a objetos como primeiro passo de design. Em outras palavras, é proposta uma técnica de modelagem sob uma estratégia dirigida por comportamento (privilegiando, assim, o aspecto dinâmico dos sistemas) com o suficiente poder de expressão para, ao mesmo tempo, permitir a modelagem de sistemas de informação no nível conceitual e derivar dos modelos dinâmicos obtidos uma representação estrutural orientada a objetos. 0 sistema, na concepção desta proposta, é composto por um conjunto de processos concorrentes, cada um dos quais recebe um estimulo do ambiente, realiza um tratamento especifico sobre ele e gera para o ambiente uma resposta. Os estímulos externos são decompostos em conjuntos de eventos concorrentes tratados no interior do processo. As ações realizadas no interior do mesmo são compostas nas respostas geradas para o exterior. Os processos são modelados comportamentalmente, utilizando o formalismo proposto High-Level Statecharts (HLS). HLS é uma extensão dos statecharts de Harel. As principais extensões propostas são a introdução de estados "parametrizados" usando variáveis e a representação genérica de conjuntos de estados concorrentes e exclusivos. 0 modelo de processos e desintegrado em unidades de comportamento que tratam das mesmas variáveis. Estas unidades são integradas em um modelo de ciclos de vida para estas variáveis. Finalmente, apos a aplicação da técnica de modelagem conceitual, e obtido um modelo estrutural orientado a objetos. Este modelo e derivado utilizando unicamente informações contidas nos modelos dinâmicos gerados no processo da técnica proposta. No modelo estrutural são identificadas classes, objetos, atributos, associações estáticas, hierarquias de herança e operações. Todo o processo e exemplificado utilizando o problema padrão de preparação de congressos da IFIP. / Object-Oriented Modeling (OOM) is the process of construction of systems models, through an identification and definition of a set of relating objects. These objects have a collaborative behavior according to the system requirements previously defined. This definition includes three modeling aspects or dimensions: object structural dimension, behavior dynamic dimension and requirements functional dimension. Depending on a relative importance of each dimension, three possible strategies to drive OOM are defined. The strategies are: data-driven, behavior-driven and process-driven. Process-driven strategy is obsolete. Nowadays, data-driven is the dominant strategy in the world of OOM techniques. Behavior-driven strategy suggests both internal and external system behaviors define its object structure. This idea is attractive because it allows a late encapsulation in the OOM. As explained in this work, the main advantage to use object-orientation is for implementation. So, to object-orient or not to object-orient is a design decision. If encapsulation is introduced in the very beginning of systems modeling, the structural continuity is achieved at the cost of pulling OOM closer to design. In this context, the work presents a process of systems conceptual modeling using a behavioral point of view. This process introduces object-oriented encapsulation lately as a first step in the design phase. In other words, this work is a proposal of a modeling technique under a behavior-driven strategy (focusing the dynamic aspect of the systems) with enough expression power to model information systems at conceptual level and, at the same time, to derive of an object-oriented structural representation from the dynamic models. As conceived in the proposal, a system is composed by a set of concurrent processes. Each process receives a stimuli from the environment, makes a specific treatment on it and generates a response to the environment. The external stimuli is decomposed into a set of concurrent events which are internally handled by the process. Actions internally performed by the process are composed into a response which is sent outside the process. Processes are behaviorally modeled using a proposed formalism called High-Level Statecharts (HLS). HLS is a extension of Harel's statecharts. The main extensions proposed are parameterized states using variables and generic representation of concurrent and exclusive sets of states. Process model is disintegrated into behavior units handling the same variables. The units are integrated into a life cycle model for these variables. Finally, after the modeling technique has been applied, an object-oriented structural model is obtained. This model is derived exclusively using information from the dynamic models constructed during the modeling process. Classes, objects, attributes, static associations, inheritance hierarchies and operations in the structural model are identified. Examples used in all the modeling process are taken from the standard problem of IFIP conference.

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