This report identifies how Tuxedo fits into the scheme of distributed database processing. Tuxedo is an On-Line Transaction Processing (OLTP) system. Tuxedo was studied because it is the oldest and most widely used transaction processing system on UNIX. That means that it is established, extensively tested, and has the most tools available to extend its capabilities. The disadvantage of Tuxedo is that newer UNIX OLTP systems are often based on more advanced technology. For this reason, other OLTPs were examined to compare their additional capabilities with those offered by Tuxedo. As discussed in Sections I and II, Tuxedo is modeled according to the X/Open's Distributed Transaction Processing (DTP) model. The DTP model includes three pieces: Application Programs (APs), Transaction Monitors (TMs), and Resource Managers (RMs). Tuxedo provides a TM in the model and uses the XA specification to communicate with RMs (e.g. Informix). Tuxedo's TX specification, which defines communications between the APs and TMs is also being considered by X/Open as the standard interface between APs and TMs. There is currently no standard interface between those two pieces. Tuxedo conforms to all X/Open's current standards related to the model. Like the other major OLTPs for UNIX, Tuxedo is based on the client/server model. Tuxedo expands that support to include both synchronous and asynchronous service calls. Tuxedo calls that extension the enhanced client/server model. Tuxedo also expands their OLTP support to allow distributed transactions to include databases on IBM compatible Personal Computers (PCs) and proprietary mainframe (Host) systems. Tuxedo calls this extension Enterprise Transaction Processing (ETP). The name enterprise comes from the fact that since Tuxedo supports database transactions supporting UNIX, PCs. and Host computers, transactions can span the computer systems of entire businesses, or enterprises. Tuxedo is not as robust as the distributed database system model presented by Date. Tuxedo requires programmer participation in providing the capabilities that Date says the distributed database manager should provide. The coordinating process is the process which is coordinating a global transaction. According to Date's model, agents exist on remote sites participating in the transaction in order to handle the calls to the local resource manager. In Tuxedo, the programmer must provide that agent code in the form of services. Tuxedo does provide location transparency, but not in the form Date describes. Date describes location transparency as controlled by a global catalog. In Tuxedo, location transparency is provided by the location of servers as specified in the Tuxedo configuration file. Tuxedo also does not provide replication transparency as specified by Date. In Tuxedo, the programmer must write services which maintain replicated records. Date also describes five problems faced by distributed database managers. The first problem is query processing. Tuxedo provides capabilities to fetch records from databases, but does not provide the capabilities to do joins across distributed databases. The second problem is update propagation. Tuxedo does not provide for replication transparency. Tuxedo does provide enough capabilities for programmers to reliably maintain replicated records. The third problem is concurrency control, which is supported by Tuxedo. The fourth problem is the commit protocol. Tuxedo's commit protocol is the two-phase commit protocol. The fifth problem is the global catalog. Tuxedo does not have a global catalog. The other comparison presented in the paper was between Tuxedo and the other major UNIX OL TPs: Transarc's Encina, Top End, and CICS. Tuxedo is the oldest and has the largest market share. This gives 38 Tuxedo the advantage of being the most thoroughly tested and the most stable. Tuxedo also has the most tools available to extend its capabilities. The disadvantage Tuxedo has is that since it is the oldest, it is based on the oldest technology. Transarc's Encina is the most advanced UNIX OLTP. Encina is based on DCB and supports multithreading. However, Encina has been slow to market and has had stability problems because of its advanced features. Also, since Encina is based on DCB, its success is tied to the success of DCB. Top End is less advanced than Encina, but more advanced than Tuxedo. It is also much more stable than Encina. However. Top End is only now being ported from the NCR machines on which it was originally built. CICS is not yet commercially available. CICS is good for companies with CICS code to port to UNIX and CICS programmers who are already experts. The disadvantage to CICS is that companies which work with UNIX already and do not use CICS will find the interface less natural than Tuxedo, which originated under UNIX. / Master of Science

The Ph.D. project has evolved from focusing on the technical problem of the integration and interoperability of an assemblage of complex systems and SoS within a flight training system to development of a workflow process using frameworks to aid the decision making process for the selection of optimal flight training blending mixes. The focus of the research involved developing a methodology to satisfy research project proposal requirements agreed upon with the industrial sponsor. This thesis investigates the complexity of a modern flight training systems and the need for understanding that it is supported by a complex Family of Systems (FoS) including Virtual Reality Training Environments such as flight simulators, to live training aircraft with various configurations of avionic controls. One of the key technical problems today is how best to develop and assemble a family of flight training system into an integrated Live/Synthetic mix for aircrew training to optimise organisation and training objectives. With the increased use of emulation/synthetic data on aircraft for live training, the synthetic boundary is becoming increasingly blurred. Systematic consideration of the most appropriate blend is needed. The methodology used in the research is model driven and the architecture produced is described at a level of abstraction to enable communication to all stakeholders for the means of understanding the structure involved in the system design process. Relational Oriented Systems Engineering and Technology Trade-Off Analysis (ROSETTA) frameworks are described using Model Based Systems Engineering (MBSE) techniques for supporting capability based trade-off decisions for selection of optimal flight training FoS mixes dependent on capability. The research proposes a methodology and associated methods including a high-level systematic closed loop information management structure for blended device/tool aircrew training and a modelling and analysis approach for the FoS aviation training problem to enhance the existing training programmes to provide a more efficient and agile training environment. The mathematical formalisms used provide a method of quantifying subjective opinions and judgements for trade studies to be accomplished on the suitability of technology for each student pilot in relation to training and organisational objectives. The methodology presented is by no means a final solution, but a path for further research to enable a greater understanding of the suitability of training tools/technology used to train individual pilots at various stages throughout the training pipeline lifecycle(s).

Much of industry is seeking scope economies, but this requires more complex and flexible product realisation. Modelling technologies have potential to support the life cycle engineering of both Economies of Scope and Scale (EoSS) manufacturing systems. However when companies operate in dynamic environments it is not sufficient to model manufacturing systems in isolation. Rather a holistic modelling methodology is needed which can create structural and behavioural models of dependencies between the manufacturing systems, and the business and engineering environments in which they operate; so that a suitable balance between economies of scope and scale can be achieved. This thesis describes the conception and development of a step wised Extended Modelling Methodology (EMM) which facilitates reasoning, and related decision making, about EoSS manufacturing systems. The EMM was conceived from exploratory research in two SMEs, following which it was applied and case tested in a large manufacturing company. Little academic attention to date has been paid to theorising about the link between ‘Economies of Scope and Scale (EoSS) phenomenon' and ‘manufacturing systems design'. Hence many questions about EoSS manufacturing remain unanswered, such as: (1) academic communities need to know what EoSS actually means and how state-of-the-art modelling can support qualitative and quantitative analysis of EoSS system phenomenon; and (2) industry needs to know how they can benefit from EoSS, what attended costs they might incur, and what best balance between scope and scale economies can be achieved. With these general requirements in mind the thesis reports on the conception and industrial application of the EMM. This has: (A) developed new ideas about EoSS, which can be used to characterise EoSS phenomenon; (B) introduced a new way of visualising architectural aspects of EoSS at multiple-levels of abstraction; and (C) with reference to case studies has illustrated the use of multi-level modelling to enable predictions to be made about EoSS benefits and costs.

The High Redundancy Actuator (HRA) project investigates a novel approach to fault tolerant actuation, which uses a high number of small actuation elements, assembled in series and parallel in order to form a single intrinsically fault tolerant actuator. Element faults affect the maximum capability of the overall actuator, but through control techniques, the required performance can be maintained. This allows higher levels of reliability to be attained in exchange for less over-dimensioning in comparison to conventional redundancy techniques. In addition, the combination of both serial and parallel elements provides intrinsic accommodation of both lock-up and loose faults. Research to date has concentrated on HRAs based on electromechanical technology, of relatively low order, controlled through passive Fault Tolerant Control (FTC) methods. The objective of this thesis is to expand upon this work. HRA configurations of higher order, formed from electromagnetic actuators are considered. An element model for a moving coil actuator is derived from first principles and verified experimentally. This element model is then used to form high-order, non-linear HRA models for simulation, and reduced-order representations for control design. A simple, passive FTC law is designed for the HRA configurations, the results of which are compared to a decentralised, active FTC approach applied through a framework based upon multi-agent concepts. The results indicate that limited fault tolerance can be achieved through simple passive control, however, performance degradation occurs, and requirements are not met under theoretically tolerable fault levels. Active FTC offers substantial performance improvements, meeting the requirements of the system under the vast majority of theoretically tolerable fault scenarios. However, these improvements are made at the cost of increased system complexity and a reliance on fault detection. Fault Detection (FD) and health monitoring of the HRA is explored. A simple rule-based FD method, for use within the active FTC, is described and simulated. An interacting multiple model FD method is also examined, which is more suitable for health monitoring in a centralised control scheme. Both of these methods provide the required level of fault information for their respective purposes. However, they achieve this through the introduction of complexity. The rule-based method increases system complexity, requiring high levels of instrumentation, and conversely the interacting multiple model approach involves complexity of design and computation. Finally, the development of a software demonstrator is described. Experimental rigs at the current project phase are restricted to relatively low numbers of elements for practical reasons such as cost, space and technological limitations. Hence, a software demonstrator has been developed in Matlab/Simulink which provides a visual representation of HRAs with larger numbers of elements, and varied configuration for further demonstration of this concept.

The lack of interoperability between Pay‐TV service providers and a horizontally integrated business transaction model have compromised the competition in the Pay‐TV market. In addition, the lack of interactivity with customers has resulted in high churn rate and improper security measures have contributed into considerable business loss. These issues are the main cause of high operational costs and subscription fees in the Pay‐TV systems. This paper presents a novel end‐to‐end system architecture for Pay‐TV systems cooperating mobile and broadcasting technologies. It provides a cost‐effective, scalable, dynamic and secure access control mechanism supporting converged services and new business opportunities in Pay‐TV systems. It enhances interactivity, security and potentially reduces customer attrition and operational cost. In this platform, service providers can effectively interact with their customers, personalise their services and adopt appropriate security measures. It breaks up the rigid relationship between a viewer and set‐top box as imposed by traditional conditional access systems, thus, a viewer can fully enjoy his entitlements via an arbitrary set‐top box. Having thoroughly considered state‐of‐the‐art technologies currently being used across the world, the thesis highlights novel use cases and presents the full design and implementation aspects of the system. The design section is enriched by providing possible security structures supported thereby. A business collaboration structure is proposed, followed by a reference model for implementing the system. Finally, the security architectures are analysed to propose the best architecture on the basis of security, complexity and set‐top box production cost criteria.

Semiconductor diode lasers are successful tools in atomic spectroscopy. They are routinely used in frequency conversion applications to develop devices that access regions of the spectrum not directly available. This thesis describes the practical application of novel violet diode laser systems and their possible inclusion in spectroscopic systems. The design, assembly and successful operation of a doubly resonant optical parametric oscillator is described. There is discussion of the spectral behaviour of the device and the potential for pumping with a violet diode laser. Methods to adapt the output from the solitary diode devices are demonstrated with the use of microlensed diode lasers and extended cavity configurations. Details of the current tuning, linewidth and smooth tuning characteristics of a number of the lasers used are given. A commercial violet diode laser is used within an extended cavity to measure the hyperfine structure of atomic indium from a hollow cathode galvatron source at room temperature. Stabilisation of the diode laser to a line from the indium spectrum is attempted. The remainder of the thesis is concerned with the development of techniques to deliver clearer and more precise spectral information about trace species. Microlensed red and violet diode lasers are used to generate light at 254nm via sum frequency generation for the direct detection and modulation spectroscopy of mercury vapour, with microlensed lasers with modulation allowing more accurate discrimination between spectral features than direct absorption measurements. In addition Raman tweezers modulation spectroscopy is undertaken to investigate polymer microspheres and biological cell samples where the use of the modulation technique demonstrated improvements in the acquisition time and clarity of spectra through increased signal to noise and rejection of background fluorescence effects. A comparison between the direct and modulation techniques for all the systems indicates the greater sensitivity of the modulation technique.

<p>Kroz istraživanja je postavljen i razvijen kompleksan model sistema<br />identifikacije procesnih parametara štampe na osnovama<br />savremenih programskih sistema i alata koji omogućuju značajno<br />ubrzanje procesa dolaska do rešenja čime su se unapredili grafički<br />proizvodni procesi i procesi sticanja i proširivanja znanja. Model<br />je baziran na integrativnim modulima koga čine, sistem<br />identifikacije procesnih parametara štampe na osnovi sistema<br />zasnovanih na algoritamskoj programskoj strukturi, sistem<br />identifikacije procesnih parametara štampe na osnovi sistema<br />zasnovanih na principima gradnje ekspernih sistema i sistem<br />identifikacije procesnih parametara štampe na osnovi sistema<br />zasnovanih na učenju na daljinu.</p> / <p>The complex model of the printing processing parameter identification<br />system is set and developed through research on the basis of modern<br />software systems and tools that enable you to significantly speed up the<br />process reaching solutions which have improved graphics production<br />processes and the processes of acquiring and expanding knowledge. The<br />model is based on the integration modules, which consist the printing<br />processing parameter identification system based on algorithmic structure,<br />the printing processing parameter identification system based on the<br />construction principles of expert systems and the printing processing<br />parameter identification system based on distance learning principles.</p>

Reúso de software, principalmente quando apoiado por ferramentas computacionais, é uma forma de enfrentar os constantes desafios da Engenharia de Software em aumentar a produtividade e qualidade no desenvolvimento de software. Diversos ambientes de apoio ao reúso de software têm sido propostos, em sua maioria com objetivos específicos, por exemplo, repositórios de componentes, ferramentas para geração de aplicações e ferramentas para configuração de linhas de produtos. Entretanto, a integração desses ambientes é, muitas vezes, deficiente e deixada por conta do próprio desenvolvedor. Por outro lado, Sistemas-de-Sistemas (SoS) constituem uma forma de integrar sistemas independentes e seus relacionamentos, formando um todo maior que a soma das partes. Dessa forma, o SoS permite alcançar objetivos complexos que não poderiam ser facilmente alcançados individualmente pelos seus sistemas constituintes. Em um SoS, comportamentos emergentes podem surgir a qualquer momento ou terem sido previamente implementados. Por serem recentes, os conceitos de SoS ainda apresentam uma vasta gama de tópicos em aberto, entre eles sua aplicação a ambientes de reúso de software. Assim, neste trabalho, investigou-se como integrar ambientes de reúso com base nos conceitos de SoS. O SoS resultante, denominado SoS-Reúso, visa facilitar a implementação de comportamentos emergentes relacionados ao reúso de software. Com isso, pode-se potencializar a atividade de reúso, facilitando a busca por ativos reusáveis em diferentes sistemas constituintes. Para colocar em prática essa ideia, desenvolveu-se um simulador do SoS-Reúso, denominado P-SoS-Reúso. Realizou-se um estudo qualitativo da usabilidade e adequação funcional do P-SoS-Reúso, a fim de obter do usuário feedbacks em relação ao seu uso. A abordagem utilizada no desenvolvimento do SoS-Reúso poderá ser adaptada futuramente para integrar outros tipos de sistemas, os quais poderiam se beneficiar da abordagem baseada em SoS. / Software reuse, specially when supported by computational tools, is a way to face the constant challenges of Software Engineering in increasing productivity and quality in software development. Several enviroments to support software reuse have been proposed, mostly for specific purposes, for example, component repositories, application generation tools, and tools for configuring product lines. However, the integration among these environments is often deficient and left to the developerss responsibility. On the other hand, Systems-of-Systems (SoS) is a way of integrating independent systems and their relationships, forming a whole greater than the sum of the parts. In this way, SoS allows us to achieve complex goals that could not be easily achieved individually by their constituent systems. In a SoS, emergent behaviors can arise at any time or have been previously implemented. Because they are recent, SoS concepts still feature a variety of open research topics, including their application to software reuse environments. Thus, in this work, we investigated how to integrate reuse environments based on SoS concepts. The resulting SoS, called SoS-Reuse, aims to facilitate the implementation of emergent behaviors related to software reuse. This allows to enhance the reuse activity, facilitating the search for reusable assets in different constituent systems. To implement this idea, it was developed a simulator of the SoS-Reuse, named P-SoS-Reuse. An qualitative study of the usability and functional adequacy of the P-SoS-Reuse was performed to obtain feedback from users regarding its use. The approach used to develop SoS-Reuse can be adapted in the future to integrate other types of systems, which could benefit from the SoS-based approach.

Systems-of-Systems (SoS) have performed an important and even essential role to the whole society and refer to complex softwareintensive systems, resulted from interoperability of independent constituent systems that work together to achieve more complex missions. SoS have emerged specially in critical application domains and, therefore, high level of quality must be assured during their development and evolution. However, dealing with quality of SoS still presents great challenges, as SoS present a set of unique characteristics that can directly affect the quality of such systems. Moreover, there are not comprehensive models that can support the quality evaluation of SoS. Motivated by this scenario, the main contribution of this Masters project is to present a SoS Evaluation Model, more specifically, addressing the crisis/emergency management domain, built in the context of a large international research project. The proposed model covers important evaluation activities and considers all SoS characteristics and challenges not usually addressed by other models. This model was applied to evaluate a crisis/emergency management SoS and our results have shown it viability to the effective management of the SoS quality. / Sistemas-de-Sistemas (SoS, do inglês Systems-of-Systems) realizam um importante e até essencial papel na sociedade. Referem-se a complexos sistemas intensivos em software, resultado da interoperabilidade de sistemas constituintes independentes que trabalham juntos para realizar missões mais complexas. SoS têm emergido especialmente em domínios de aplicação crítica, portanto, um alto nível de qualidade deve ser garantido durante seu desenvolvimento e evolução. Entretanto, lidar com qualidade em SoS ainda apresenta grandes desafios, uma vez que possuem um conjunto de características únicas que podem diretamente afetar a qualidade desses sistemas. Além disso, não existem modelos abrangentes para o suporte à avaliação de qualidade de SoS. Motivado por este cenário, a principal contribuição deste projeto de mestrado é apresentar um modelo de avaliação para SoS, especialmente destinado ao domínio de gerenciamento de crises e emergências. Este modelo foi construído no contexto de um grande projeto de pesquisa internacional, e cobre as mais importantes atividades de avaliação, considerando as principais características e desafios de SoS geralmente não abordados por outros modelos. Este modelo foi aplicado na avaliação de um SoS de gerenciamento de crises e emergência, e nossos resultados têm mostrado sua viabilidade para o efetivo gerenciamento da qualidade de SoS.

Context: Software-intensive systems have been increasingly interoperated forming alliances termed as Systems-of-Systems (SoS). SoS comprises a collection of systems joined to achieve a set of missions that none of the systems can accomplish on its own. Each constituent system keeps its own management, goals, and resources while coordinating within the SoS and adapting to meet SoS goals. Applications of SoS range from traffic control to emergency response and crisis management. As SoS often support critical domains, such systems must be correct by dealing with malfunction or defects and avoiding failures that could cause extensive damage and losses to the users. Problem: Correct SoS operations depend on a precise specification and a rigorous attestation of its operational consistency. However, besides limitations on languages to jointly capture SoS structure and behavior, predictions on the SoS operational consistency rely on constituent systems not totally known at design-time. Therefore, SoS have been developed and deployed without evaluating their operations, since current languages do not support such precision in evaluation. Objectives: This thesis provides solutions founded on a formal architectural description language to support an early evaluation of SoS operation regarding SoS structure and behavior by means of simulations. Contribution: The main contributions of this project comprise (i) a model transformation approach for automatically producing simulation models from SoS software architecture descriptions, combining SoS structure and behavior description in a same solution, (ii) a SoS software architecture evaluation method for SoS operation prediction considering the inherent changes that can occur, (iii) environment modelling and automatic generation of stimuli generators to sustain the SoS simulation, delivering data to feed such simulation, and (iv) a method for the automatic synchronization between the runtime descriptive architecture (changed at runtime due to dynamic architecture) and its original prescriptive architecture based on model discovery and recovery mechanisms and a backward model transformation. Evaluation: We conducted case studies to assess our solutions using Flood Monitoring SoS and Space SoS. Results: Our solutions support a high accuracy to (i) produce fault-free and fully operational simulations for SoS software architectures, (ii) support evaluation and prediction of SoS operation at design-time, (iii) automatically generate stimuli generators to sustain and feed the simulation execution, and (iv) maintain the synchronization between the runtime architecture and the intended version of the SoS architecture. Conclusions: We concluded that the proposed solutions advance the state of the art in SoS software architecture evaluation by offering solutions to predict the SoS operations effectiveness to maintain a continuous operation despite architectural changes, providing more trust for users that futurely shall rely on SoS services. / Contexto: Sistemas intensivos em software tem sido interoperados para formar alianças conhecidas como Sistemas-de-Sistemas (SoS). Domínios de aplicação de SoS variam do controle de tráfego ao gerenciamento de situações de crises e emergência. Devido à criticidade destes domínios, tais sistemas precisam ser confiáveis e robustos, lidando com potenciais defeitos e mal funcionamento, e evitando falhas que poderiam causar ameaças à integridade dos usuários. Problema: O funcionamento correto de um SoS depende da especificação precisa e da garantia rigorosa da consistência de suas operações. Entretanto, além das limitações nas linguagens quanto à especificação de ambos estrutura e comportamento do SoS, prever seu comportamento depende da especificação de constituintes que não são totalmente conhecidos em tempo de projeto e de seu comportamento emergente. Neste sentido, SoS têm sido desenvolvidos e implantados sem a devida avaliação de seus comportamentos, uma vez que as linguagens disponíveis atualmente não dão suporte a uma especificação precisa destes comportamentos. Objetivos: Este projeto de doutorado relata avanços teóricos e práticos fundamentados em uma linguagem de descrição arquitetural formal para permitir a predição e avaliação do comportamento e estrutura dos SoS com base em simulações. Contribuições: As principais contribuições deste projeto envolvem (i) uma transformação de modelos para produzir automaticamente modelos de simulação para descrições de arquitetura de software de SoS, combinando estrutura e comportamento em uma mesma solução, (ii) um método de avaliação de arquitetura de software de SoS para prever o comportamento do SoS considerando sua dinâmica inerente, (iii) modelagem do ambiente e derivação automática de geradores de estímulos entregando dados continuamente e sustentando a execução de simulações de SoS, e (iv) um método para promover a sincronização automática entre modelos descritivos e prescritivos de arquitetura de software de SoS baseados em mecanismos de descoberta e recuperação de modelos, e transformação de modelos reversa. Avaliação: Estudos de caso foram conduzidos para avaliar as soluções nos domínios de Monitoramento de Enchentes e Espacial. Resultados: As abordagens propostas exibem alta acurácia no que tange (i) a produzir simulações operacionais e sem falhas para arquiteturas de software de SoS, (ii) ao suporte á avaliação, ainda em tempo de projeto, do comportamento que emerge da operação do SoS, (iii) à derivação automática de geradores de estímulos para entrega contínua de dados e manutenção da execução das simulações geradas, e (iv) à manutenção do alinhamento entre os modelos descritivos e prescritivos da arquitetura do SoS avaliado. Conclusões: Conclui-se que as abordagens propostas avançam o estado da arte no projeto de arquiteturas de Software de SoS ao permitir prever, em tempo de projeto, como o SoS vai operar em tempo de execução, permitindo estabelecer estratégias para manter a simulação rodando, e sua operação contínua, mesmo com as mudanças arquiteturais inerentes ao seu funcionamento, provendo mais confiabilidade para os usuários futuramente dependerão de seus serviços.