Some disciplines are inherently complex and challenging to learn. This research attempts to design an instructional strategy for CBL systems to simplify learning certain complex domains. Firstly, problem transformation, a constructionist instructional technique, is used to promote active learning by encouraging students to construct more complex artefacts based on less complex ones. Scaffolding is used at the initial learning stages to alleviate the difficulty associated with complex transformation processes. The proposed instructional strategy brings various techniques together to enhance the learning experience. A functional prototype is implemented with Object-Z as the exemplar subject. Both objective and subjective evaluations using the prototype indicate that the proposed CBL system has a statistically significant impact on learning a complex domain. CBL systems include Learner models to provide adaptable support tailored to individual learners. Bayesian theory is used in general to manage uncertainty in Learner models. In this research, a fuzzy logic based locally intelligent Learner model is utilized. The fuzzy model is simple to design and implement, and easy to understand and explain, as well as efficient. Bayesian theory is used to complement the fuzzy model. Evaluation shows that the accuracy of the proposed Learner model is statistically significant. Further, opening Learner model reduces uncertainty, and the fuzzy rules are simple and resemble human reasoning processes. Therefore, it is argued that opening a fuzzy Learner model is both easy and effective. Scaffolding requires formative assessments. In this research, a confidence based multiple test marking scheme is proposed as traditional schemes are not suitable for measuring partial knowledge. Subjective evaluation confirms that the proposed schema is effective. Finally, a step-by-step methodology to transform simple UML class diagrams to Object-Z schemas is designed in order to implement problem transformation. This methodology could be extended to implement a semi-automated translation system for UML to Object Models.

Aspect oriented programming (AOP) introduces new and powerful modularization constructs. The aspect module is used to encapsulate crosscutting concerns, which otherwise would remain tangled and scattered. The idea of encapsulating crosscutting concerns rapidly expanded to earlier phases in the development cycle, including requirement analysis (aspect oriented requirement engineering, AORE) and design (aspect oriented modeling, AOM). The overall application of aspect orientation concepts is known as aspect oriented software development (AOSD). AOP is not yet a mainstream practice. Particularly AOSD is still in its early stages. This is reflected in the lack of reports of full development cycles using aspect oriented approaches, especially using industrial case studies. Furthermore, the power of aspects comes at the price of new challenges, one of them is that systems built using aspects are more difficult to understand. The crosscutting nature of aspects allows them to alter the behavior of many other modules. As a result, aspects may interact in unintended and unanticipated ways. This problem is known as aspect interactions. In this work we deal with the aspect interaction problem in the context of an industrial domain: slots machines. We perform a complete development cycle of the slot machine software. This is, to the best of our knowledge, the first complete industrial case of study of aspect orientation. Through this experience we discovered the limitations with regard to aspect interactions, of some emblematic aspect oriented approaches for requirement engineering, design and implementation. The contribution of this work is threefold. Firstly, we contribute with the evaluation and extensions to some of AORE and AOM approaches, in order to provide explicit support for aspect interactions in requirement analysis and design phases. We also evaluate the implementation of interactions using a static and a dynamic AOP language, and propose an AspectJ extension that copes with aspect interactions. Secondly, this work is the first report of a complete aspect oriented development cycle of an industrial case study. Thirdly, this work provides a complex case study that presents several business logic crosscutting concerns, which in turn exhibit numerous aspect interactions, that serves as a challenging test bed for upcoming AOSD approaches.

With the rise of modern programming languages like Java that include native support for multi-threading, the issue of concurrency in graphical applications becomes more and more important. Traditional graphical component libraries for Java have always used the threading concepts provided by the language very carefully, telling the programmer that the use of threads in this context is often unnecessarily burdensome and complex. On the other hand, experience gained from systems like Inferno or BeOS shows that the use of concurrency in graphical applications is clearly manageable and leads to a different program design, once you dissociate the application from the limitations of the GUI library. This thesis describes the design of a general architecture that allows for the separation of a program´s user interface from the application logic using thread communication. It enables the use of concurrency in the application code without requiring any degree of thread-safety at the native interface component level.

Ao final desta pesquisa deseja-se que haja uma metodologia eficiente, cuja finalidade será auxiliar o usuário na transformação de modelos matemáticos e computacionais codificados para computadores sequenciais, em modelos paralelos otimizados para executarem em microcomputadores pessoais modernos, constituídos de CPU com múltiplos núcleos ou de híbridos (CPU + GPGPU) integrados no mesmo chip, com ou sem processadores gráficos (GPGPU) densamente paralelos instalados, mantendo a qualidade de seus resultados originais, com respeito à sua precisão numérica, mas com uma diminuição considerável no tempo de processamento. A emergência, em meados da década 2000, dessas novas arquiteturas de hardware elevou a capacidade de processamento dos microcomputadores pessoais aos patamares dos computadores de grande porte de apenas alguns anos atrás. Este trabalho de pesquisa apresenta duas metodologias, onde a primeira metodologia é composta de três partes e a segunda de duas partes. Somente a terceira parte da primeira metodologia é dependente de tecnologias de hardware. / At the end of this research project, an efficient methodology is expected with the purpose of assisting users in the processing of mathematical and computer models coded for sequential computers in parallel models that are optimized to run on modern personal computers, consisting of a CPU with multiple or hybrid (CPU + GPGPU) cores integrated into the same chip, with or without massively parallel graphics processors (GPGPU) installed. This will ensure the original quality of the results with respect to numerical accuracy, but with a considerable reduction in processing time. The emergence of these new hardware architectures in the mid-2000s increased the processing power of personal computers to the levels of mainframe computers from just a few years previously. This research work presents two methodologies, where the first methodology is composed of three parts and the second methodology is composed of two parts. Only the third part of the first methodology is dependent on hardware technologies.

Ao final desta pesquisa deseja-se que haja uma metodologia eficiente, cuja finalidade será auxiliar o usuário na transformação de modelos matemáticos e computacionais codificados para computadores sequenciais, em modelos paralelos otimizados para executarem em microcomputadores pessoais modernos, constituídos de CPU com múltiplos núcleos ou de híbridos (CPU + GPGPU) integrados no mesmo chip, com ou sem processadores gráficos (GPGPU) densamente paralelos instalados, mantendo a qualidade de seus resultados originais, com respeito à sua precisão numérica, mas com uma diminuição considerável no tempo de processamento. A emergência, em meados da década 2000, dessas novas arquiteturas de hardware elevou a capacidade de processamento dos microcomputadores pessoais aos patamares dos computadores de grande porte de apenas alguns anos atrás. Este trabalho de pesquisa apresenta duas metodologias, onde a primeira metodologia é composta de três partes e a segunda de duas partes. Somente a terceira parte da primeira metodologia é dependente de tecnologias de hardware. / At the end of this research project, an efficient methodology is expected with the purpose of assisting users in the processing of mathematical and computer models coded for sequential computers in parallel models that are optimized to run on modern personal computers, consisting of a CPU with multiple or hybrid (CPU + GPGPU) cores integrated into the same chip, with or without massively parallel graphics processors (GPGPU) installed. This will ensure the original quality of the results with respect to numerical accuracy, but with a considerable reduction in processing time. The emergence of these new hardware architectures in the mid-2000s increased the processing power of personal computers to the levels of mainframe computers from just a few years previously. This research work presents two methodologies, where the first methodology is composed of three parts and the second methodology is composed of two parts. Only the third part of the first methodology is dependent on hardware technologies.

Future space missions, such as Mars Science Laboratory, suggest the engineering of some of the most complex man-rated autonomous software systems. The present process-oriented certification methodologies are becoming prohibitively expensive and do not reach the level of detail of providing guidelines for the development and validation of concurrent software. Time and concurrency are the most critical notions in an autonomous space system. In this work we present the design and implementation of the first concurrency and time centered framework for product-oriented software certification of autonomous space systems. To achieve fast and reliable concurrent interactions, we define and apply the notion of Semantically Enhanced Containers (SEC). SECs are data structures that are designed to provide the flexibility and usability of the popular ISO C++ STL containers, while at the same time they are hand-crafted to guarantee domain-specific policies, such as conformance to a given concurrency model. The application of nonblocking programming techniques is critical to the implementation of our SEC containers. Lock-free algorithms help avoid the hazards of deadlock, livelock, and priority inversion, and at the same time deliver fast and scalable performance. Practical lock-free algorithms are notoriously difficult to design and implement and pose a number of hard problems such as ABA avoidance, high complexity, portability, and meeting the linearizability correctness requirements. This dissertation presents the design of the first lock-free dynamically resizable array. Our approach o ers a set of practical, portable, lock-free, and linearizable STL vector operations and a fast and space effcient implementation when compared to the alternative lock- and STM-based techniques. Currently, the literature does not offer an explicit analysis of the ABA problem, its relation to the most commonly applied nonblocking programming techniques, and the possibilities for its detection and avoidance. Eliminating the hazards of ABA is left to the ingenuity of the software designer. We present a generic and practical solution to the fundamental ABA problem for lock-free descriptor-based designs. To enable our SEC container with the property of validating domain-specific invariants, we present Basic Query, our expression template-based library for statically extracting semantic information from C++ source code. The use of static analysis allows for a far more efficient implementation of our nonblocking containers than would have been otherwise possible when relying on the traditional run-time based techniques. Shared data in a real-time cyber-physical system can often be polymorphic (as is the case with a number of components part of the Mission Data System's Data Management Services). The use of dynamic cast is important in the design of autonomous real-time systems since the operation allows for a direct representation of the management and behavior of polymorphic data. To allow for the application of dynamic cast in mission critical code, we validate and improve a methodology for constant-time dynamic cast that shifts the complexity of the operation to the compiler's static checker. In a case study that demonstrates the applicability of the programming and validation techniques of our certification framework, we show the process of verification and semantic parallelization of the Mission Data System's (MDS) Goal Networks. MDS provides an experimental platform for testing and development of autonomous real-time flight applications.

Future space missions, such as Mars Science Laboratory, suggest the engineering of some of the most complex man-rated autonomous software systems. The present process-oriented certification methodologies are becoming prohibitively expensive and do not reach the level of detail of providing guidelines for the development and validation of concurrent software. Time and concurrency are the most critical notions in an autonomous space system. In this work we present the design and implementation of the first concurrency and time centered framework for product-oriented software certification of autonomous space systems. To achieve fast and reliable concurrent interactions, we define and apply the notion of Semantically Enhanced Containers (SEC). SECs are data structures that are designed to provide the flexibility and usability of the popular ISO C++ STL containers, while at the same time they are hand-crafted to guarantee domain-specific policies, such as conformance to a given concurrency model. The application of nonblocking programming techniques is critical to the implementation of our SEC containers. Lock-free algorithms help avoid the hazards of deadlock, livelock, and priority inversion, and at the same time deliver fast and scalable performance. Practical lock-free algorithms are notoriously difficult to design and implement and pose a number of hard problems such as ABA avoidance, high complexity, portability, and meeting the linearizability correctness requirements. This dissertation presents the design of the first lock-free dynamically resizable array. Our approach o ers a set of practical, portable, lock-free, and linearizable STL vector operations and a fast and space effcient implementation when compared to the alternative lock- and STM-based techniques. Currently, the literature does not offer an explicit analysis of the ABA problem, its relation to the most commonly applied nonblocking programming techniques, and the possibilities for its detection and avoidance. Eliminating the hazards of ABA is left to the ingenuity of the software designer. We present a generic and practical solution to the fundamental ABA problem for lock-free descriptor-based designs. To enable our SEC container with the property of validating domain-specific invariants, we present Basic Query, our expression template-based library for statically extracting semantic information from C++ source code. The use of static analysis allows for a far more efficient implementation of our nonblocking containers than would have been otherwise possible when relying on the traditional run-time based techniques. Shared data in a real-time cyber-physical system can often be polymorphic (as is the case with a number of components part of the Mission Data System's Data Management Services). The use of dynamic cast is important in the design of autonomous real-time systems since the operation allows for a direct representation of the management and behavior of polymorphic data. To allow for the application of dynamic cast in mission critical code, we validate and improve a methodology for constant-time dynamic cast that shifts the complexity of the operation to the compiler's static checker. In a case study that demonstrates the applicability of the programming and validation techniques of our certification framework, we show the process of verification and semantic parallelization of the Mission Data System's (MDS) Goal Networks. MDS provides an experimental platform for testing and development of autonomous real-time flight applications.

The thesis focuses on advanced programming constructs and techniques of the Swift programming language. At the beginning programming paradigms that are supported by the Swift design (object-oriented and functional) are introduced. Concepts of each paradigm are described and Swift is then evaluated by the level of support for these paradigms. Following programming constructs are described in-depth: working with variables, optional types, enumerated types, functions and closures. Creating of custom operators and subscripts. Operations with protocols, generic types and parallel program execution. Error handling with throwing functions. Detailed explanation of value types and their differences from reference type is given too. Thesis also explains nested types and all higher-order functions in Swift. At the end are described extensions; specifically extension of computed property, initialization function, function, subscript, nested type and protocol and generic types extensions. In the last section of the thesis these advanced programming techniques are described; function chaining and composition, structure saving, performance optimization of value types, reflection in the Swift programming language and how modules and namespaces work. At the end protocol-oriented programming is introduced.

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