Thesis (M.S.)--University of Copenhagen, 1995. / "Department of Computer Science, University of Copenhagen"--Cover. "Summer 1995." Includes bibliographical references.

This thesis develops a methodology for designing resilient system-of-systems (SoS) networks. This methodology includes a capability-based resilience assessment framework, used to quantify SoS resilience. A complex networks approach is used to generate potential SoS network designs, focusing on scale-free and random network topologies, degree-based and random rewiring adaptation, and targeted and random node removal threats. Statistical design methods, specifically response surface methodology, are used to evaluate SoS networks and provide an understanding of the advantages and disadvantages of potential designs. Linear regression is used to model a continuous representation of the network design space, and determine optimally resilient networks for particular threat types. The methodology is applied to an information exchange (IE) network model (i.e., a message passing network model) and military command and control (C2) model. Results show that optimally resilient IE network topologies are random for networks with adaptation, regardless of the threat type. However, the optimally resilient adaptation method sharply transitions from being fully random to fully degree-based as threat randomness increases. These findings suggest that intermediately defined networks should not be considered when designing for resilience. Cost-benefit analysis of C2 networks suggests that resilient C2 networks are more cost-effective than robust ones, as long as the cost of rewiring network links is less than three-fourths the cost of creating new links. This result identifies a threshold for which a resilient network design approach is more cost-effective than a robust one.This thesis develops a methodology for designing resilient system-of-systems (SoS) networks. This methodology includes a capability-based resilience assessment framework, used to quantify SoS resilience. A complex networks approach is used to generate potential SoS network designs, focusing on scale-free and random network topologies, degree-based and random rewiring adaptation, and targeted and random node removal threats. Statistical design methods, specifically response surface methodology, are used to evaluate SoS networks and provide an understanding of the advantages and disadvantages of potential designs. Linear regression is used to model a continuous representation of the network design space, and determine optimally resilient networks for particular threat types. The methodology is applied to an information exchange (IE) network model (i.e., a message passing network model) and military command and control (C2) model. Results show that optimally resilient IE network topologies are random for networks with adaptation, regardless of the threat type. However, the optimally resilient adaptation method sharply transitions from being fully random to fully degree-based as threat randomness increases. These findings suggest that intermediately defined networks should not be considered when designing for resilience. Cost-benefit analysis of C2 networks suggests that resilient C2 networks are more cost-effective than robust ones, as long as the cost of rewiring network links is less than three-fourths the cost of creating new links. This result identifies a threshold for which a resilient network design approach is more cost-effective than a robust one.

This thesis presents the development and validation of a novel interface modelling methodology integrated with a system architectural analysis framework that emphasises the need to manage the integrity of deriving and allocating requirements across multiple levels of abstraction in a structured manner. The state of the art review in this research shows that there is no shared or complete interface definition model that could integrate diverse interaction viewpoints for defining system requirements with complete information. Furthermore, while existing system modelling approaches define system architecture with functions and their allocation to subsystems to meet system requirements, they do not robustly address the importance of considering well-defined interfaces in an integrated manner at each level of systems hierarchy. This results in decomposition and integration issues across the multiple levels of systems hierarchy. Therefore, this thesis develops and validates following: -Interface Analysis Template as a systematic tool that integrates diverse interaction viewpoints for modelling system interfaces with intensive information for deriving requirements. -Coupling Matrix as an architecture analysis framework that not only allocates functions to subsystems to meet requirements but also promotes consistent consideration of well-defined interfaces at each level of design hierarchy. Insights from the validation of developed approach with engineering case studies within an automotive OEM are discussed, reflecting on the effectiveness, efficiency and usability of the methods.

This thesis addresses the complexities in the design of System of Systems, by providing a flexible, case independent method to analyse and rank the alternatives that are capable of performing the desired missions or operations assigned by decision makers. Although its methods involve only low-fidelity models, these proved to be the best choice as the design space created and, consequently, the number of analysis grow explosively with the increase of available options to perform the required tasks. This is due to the combinatory approach used in the generation of the design space. Another goal is to provide a demonstration of possible improvements with the addition of ontologies to the early stages of design, especially when complex solutions are expected. This also diminishes the probability of human error by decreasing the amount of work demanded when adding alternatives or changing their characteristics, displaying again the feasible application of knowledge based and automated solutions to the engineering design process. With these advantages, the flexibility of altering the set of inputs is enhanced, adding to the resilience of the framework, as it can be attached to any available compatible ontology and perform in that specific domain without hindrance. Due to the lack of techniques and the probable cost of these once made available, the evaluation of emergence is not considered in this work, and is not reccomended to be directly done once ready for use, at least not on the full result array. Moreover, the modular implementation of the framework makes the exchange of functions a rather simple task, enabling users to adapt it to their own needs. Some immediate implementations are mentioned to greatly improve the general performance and relevance of results provided.

Context. Colossal systems that are evolving are primarily system of systems (SOS). The system of systems are characteristic of functionally independent subsystems. These subsystems exhibit heterogeneity in terms of software or hardware. Each subsystem may reflect heterogeneity in dimensions such as the system complexity, system configuration, programming language and platforms, etc. Exploratory testing (ET) is perceived to be the best for testing such systems. An enhancement to exploratory testing is the session-based test management (SBTM) where several activities form a part of each session. These activities are mainly dependent on tester and the test charter of that session. There is lack of information in existing literature regarding a standard framework to design test charters for exploratory testing which forms the main area of focus of this thesis research. Objectives. Firstly, to investigate the design of test charters in general. Secondly, to find out the factors influencing the design of test charters. Lastly, to develop a framework to design effective test charters in SOS context. Methods. A mixed method approach that incorporates both qualitative and quantitative research methods is used. This research includes the quantitative leg of the online survey along with the interviews and literature review that are qualitative in nature. Literature review has been chosen to investigate the test charter design in general. Besides, interviews and online surveys  have been used to research regarding the factors and test charter framework.  Snowball sampling method and convenience sampling method have been used to sample the research data. Moreover, thematic analysis method is used for analyzing the qualitative data while descriptive statistics is used for quantitative data analysis. Results. The design aspects of test charter are documented, the factors influencing test charter design and the framework for effective test charter design for exploratory testing are presented. Conclusions. The thesis objectives are fulfilled. The findings on how the test charters are generally designed have helped in gaining insight on the primary elements that constitute a test charter design. Further, investigating the factors influencing the test charter design has helped in knowing the main elements affecting the test charter design. Finally, the main contribution of this thesis, the developed flexible test charter framework for exploratory testing encapsulates variables that should be considered, controlled or varied systematically during the course of testing. It is deemed to act as a guideline for practitioners for effective test charter design.

System-of-Systems (SoS) refer to complex, large-scale, and sometimes critical software-intensive systems that has raised as a promising class of systems in several application domains. In parallel, software architectures play a significant role in the development of software-intensive systems, dealing with both functional and non-functional requirements. In particular, systematic processes to design SoS software architectures can tackle challenges from SoS development, including to handle collaboration of independent constituent systems with different owners, missions, and interests. Despite the relevance and necessity of software-intensive SoS for diverse application domains, most of their software architectures have been still developed in an ad hoc manner. In general, there is a lack of structured processes for architecting SoS, hindering the secure adoption of SoS, reducing possibilities of sharing common architectural solutions, and negatively impacting in the success rate for these systems. This thesis presents SOAR (\\General Process for Acknowledged SoS Software Architectures\") that supports the establishment of architectural design processes for acknowledged SoS. Conceived to provide different levels of support according to each SoS development context, it comprises a high level kernel that describes what must be done when architecting SoS and also three practices with specific activities and work products to guide how to perform architectural analysis, synthesis, and evaluation. To evaluate SOAR, three surveys, a viability study, and an experiment were conducted. Results achieved in these evaluation studies indicate that SOAR can positively support the instantiation of architecting processes for acknowledged SoS and, as a consequence, contribute to the development and evolution of these complex, software-intensive systems. / Sistemas-de-sistemas ou SoS (do inglês, \"Systems-of-Systems\"), são sistemas complexos de larga escala e, algumas vezes, críticos e intensivos a software que têm se mostrado uma classe de sistemas promissora em vários domínios de aplicação. Em paralelo, arquiteturas de software têm um papel importante no desenvolvimento de sistemas intensivos a software, tratando requisitos funcionais e não-funcionais. Processos sistemáticos para o design de arquiteturas de software de SoS podem lidar com desafios do desenvolvimento desses sistemas, incluindo a promoção da colaboração de sistemas constituintes independentes, envolvendo diferentes proprietários, missões e interesses. Embora SoS intensivos a software sejam relevantes e necessários em diversos domínios de aplicação, a maior parte de suas arquiteturas tem sido desenvolvidas de forma ad hoc. Há uma ausência de processos estruturados para arquitetar SoS, dificultando a adoção segura de SoS, reduzindo possibilidades de compartilhamento de soluções arquiteturais para problemas comuns e impactando negativamente no sucesso desses sistemas. Esta tese apresenta um processo geral para SoS reconhecidos chamado SOAR (do inglês, \"General Process for Acknowledged SoS Software Architectures\") que dá suporte ao estabelecimento de instâncias de processos para o design arquitetural desses sistemas. Concebido para prover diferentes níveis de suporte de acordo com o contexto de desenvolvimento de cada SoS, o SOAR é constituído por um kernel de alto nível que descreve o que precisa ser feito para arquitetar SoS e também por três práticas que descrevem atividades e produtos de trabalho para guiar como conduzir a análise, a síntese e a avaliação arquitetural. Na avaliação do SOAR, foram realizados três surveys, um estudo de viabilidade e um experimento. Os resultados obtidos indicam que o SOAR pode oferecer um suporte positivo na instanciação de processos para o design de SoS reconhecidos e, como consequência, contribuir para o desenvolvimento e a evolução destes sistemas complexos intensivos a software.

Sistemas de software estão cada vez mais presentes na sociedade, bem como são componentes imprescindíveis no mundo contemporâneo, uma vez que facilitam e fomentam as praticidades que os cidadãos e desenvolvedores necessitam. Esses sistemas tornam-se muito mais eficientes quando conseguem interoperar com outros, de forma que troquem recursos e não necessitem implementar essas funcionalidades de maneira individual. Os stakeholders desses sistemas buscam cada vez mais métodos que facilitem essa comunicação, de um jeito prático e sem perder a independência gerencial de cada um. Desse modo, a classe emergente de Sistema de Sistemas (SoS) ganhou uma atenção considerável, por causa de suas características intrínsecas que promovem a interoperabilidade de sistemas distintos e heterogêneos. No entanto, essa comunicação não é trivial, em razão das diferentes interfaces de cada sistema, além da presença de vários stakeholders e a falta de documentação dos sistemas constituintes, dificultando assim, a busca e o uso de cada capacidade. Assim, o objetivo deste trabalho de mestrado é estabelecer uma abordagem baseada em serviços que visa auxiliar os engenheiros de SoS, principalmente na falta de ferramentas de suporte e no esforço para procurar, compreender e adaptar componentes reutilizáveis. A abordagem proposta possui elementos fundamentais que foram utilizados como base para o desenvolvimento de um repositório para engenheiros de SoS e proprietários de sistemas constituintes, de forma organizada e bem documentada, visto que pode ser usado tanto pela comunidade de pesquisa quanto por instituições privadas. / Software systems are increasingly present in society, and consist in indispensable components in the contemporary world, since they facilitate and foster the practices that citizens and developers need. These systems become much more efficient when they can interoperate with others, so that they exchange resources and do not need to implement these features individually. Stakeholders of these systems increasingly seek methods that facilitate such communication in a practical way and without losing the managerial independence of each one. Therefore, the emerging System Of System class (SoS) gained considerable attention, because of its intrinsic characteristics that promote the interoperability of distinct and heterogeneous systems. However, this communication is not trivial, due to the different interfaces of each system, besides the presence of several stakeholders and the lack of documentation of the constituent systems, making it difficult to search and to use each capacity. Thus, the aim of this masters project is to establish a service-based approach that aims to assist SoS engineers, especially in the lack of supporting tools, in the effort to search, understand and adapt reusable components. The proposed approach has fundamental elements that were used as the basis for the development of a repository for SoS engineers and owners of constituent systems, in an organized and well documented way, since it can be used by both the research community and private institutions.

The thesis deals with technologies of goods protection. It is focused on electronic technologies of goods protection, which call EAS (electronic article surveillance) in foreign literature. The goal of this thesis is support for instruction in electronic surveillance of goods. This document systematically describes principle and technical solution recent electronic technologies of goods protection. There are mentioned advantages and disadvantages too. The other chapter deals with basic operating mode and configuration parameters of loop systems, acoustic-magnetic system and radio system. On the basis of this was suggested laboratory task. This task is use for better understanding of principles electronic surveillance of goods. Some possible attacks of electronic surveillance of goods are described at the last chapter of this thesis. This attacks was also realized.

As problems in the world become increasingly complex, designers in multiple disciplines have begun to propose swarms as a solution. The espoused benefits include flexibility, resilience, and potential for decentralized control, yet there lacks consensus on what a swarm is, what characteristics they possess, and what applications they are able to address. This study addresses these questions by creating a unified approach for understanding and analyzing swarms, called the Swarm Analysis Framework. The framework pursues three goals: 1) provide extensive analysis on the many characteristics and applications that define a swarm, 2) remain flexible enough to facilitate design, testing, analysis, and other problems in understanding swarms, and 3) outline swarm applications specific to aircraft and spacecraft based swarms. Afterwards, the Swarm Analysis Framework is used to guide a case study in which the application is a swarm was developed to study one of these aerospace applications. Ultimately, the Swarm Analysis Framework, along with its extensions improvements, should be able to act as a guide or roadmap in understanding how swarms behave across multiple disciplines.<br>

<div>The methods presented in this thesis follow the three-phase process for System-of-Systems Engineering (SoSE): Definition, Abstraction, and Implementation. It begins with problem definition, then identification of stakeholders and value measures, and then proceeds to value and cost analysis using the Modeling Architectures and Parameterization of Space (MAPS) environment, which was created for this thesis. Each of the methods are applied to the case study of a persistent platform in low-Earth orbit. In the case study, over 18,000 architectures were analyzed to determine the design characteristics that best balanced value and cost. </div><div><br></div><div>Several strategies for demonstrating On-Orbit Servicing, Assembly, and Manufacturing (OSAM) technologies in orbit have been presented to the public over time, but this thesis has defined physical architecture design options and relevant value measures. In addition, the full SoSE process was applied to an OSAM concept for the first time. This work is therefore a significant step towards providing future insight to decision makers. The dialogue on these topics and the SoSE methods should be valuable to a future OSAM market and other new ventures in the space industry. </div>