This thesis investigates the relationship between object-oriented programming languages and game models of computation. These are intuitively well matched: an object encapsulates some internal state and presents some behaviour to the world via its publicly visible methods, while a strategy for some game represents the possible interactions of a program with its environment. We work with a simple and well-understood game model. Rather than tailoring our model to match some existing programming language, we view the simplicity of our semantic setting as a virtue, and try to find the appropriate language corresponding to the model. We define a class-based, stateful object-oriented language, and give a heapbased operational semantics and an interpretation in our game model. At the heart of this interpretation lies a novel semantic treatment of the phenomenon of data abstraction. The model closely guides the design of our language, which enjoys an intermediate level of expressivity between that of first-order and general higher-order store. The agreement between the operational and game interpretations is verified by a soundness proof. This involves the development of specialised techniques and a detailed analysis of the relationship between the concrete and abstract views. We also show that definability and full abstraction hold at certain types of arbitrary rank, but are problematic at other types. We conclude by briefly discussing an extended language with a control operator, along with other extensions leading to a possible core for a more realistic programming language.

This thesis examines Recursive Markov Chains (RMCs), their natural extensions and connection to other models. RMCs can model in a natural way probabilistic procedural programs and other systems that involve recursion and probability. An RMC is a set of ordinary finite state Markov Chains that are allowed to call each other recursively and it describes a potentially infinite, but countable, state ordinary Markov Chain. RMCs generalize in a precise sense several well studied probabilistic models in other domains such as natural language processing (Stochastic Context-Free Grammars), population dynamics (Multi-Type Branching Processes) and in queueing theory (Quasi-Birth-Death processes (QBDs)). In addition, RMCs can be extended to a controlled version called Recursive Markov Decision Processes (RMDPs) and also a game version referred to as Recursive (Simple) Stochastic Games (RSSGs). For analyzing RMCs, RMDPs, RSSGs we devised highly optimized numerical algorithms and implemented them in a tool called PReMo (Probabilistic Recursive Models analyzer). PReMo allows computation of the termination probability and expected termination time of RMCs and QBDs, and a restricted subset of RMDPs and RSSGs. The input models are described by the user in specifically designed simple input languages. Furthermore, in order to analyze the worst and best expected running time of probabilistic recursive programs we study models of RMDPs and RSSGs with positive rewards assigned to each of their transitions and provide new complexity upper and lower bounds of their analysis. We also establish some new connections between our models and models studied in queueing theory. Specifically, we show that (discrete time) QBDs can be described as a special subclass of RMCs and Tree-like QBDs, which are a generalization of QBDs, are equivalent to RMCs in a precise sense. We also prove that for a given QBD we can compute (in the unit cost RAM model) an approximation of its termination probabilities within i bits of precision in time polynomial in the size of the QBD and linear in i. Specifically, we show that we can do this using a decomposed Newton’s method.

We analyse the validity of common optimisations on multi-threaded programs in two memory models—the DRF guarantee and the Java Memory Model. Unlike in the single-threaded world, even simple program transformations, such as common subexpression elimination, can introduce new behaviours in shared-memory multi-threading with an interleaved semantics. To validate such optimisations, most current programming languages define weaker semantics, called memory models, that aim to allow such transformations while providing reasonable guarantees. In this thesis, we consider common program transformations and analyse their safety in the two most widely used language memory models: (i) the DRF guarantee, which promises sequentially consistent behaviours for data race free programs, and (ii) the Java Memory Model, which is the semantics of multithreaded Java. The DRF guarantee is the semantics of Ada and it has been proposed as the semantics of the upcoming revision of C++. Our key results are: (i) we prove that a large class of elimination and reordering transformations satisfies the DRF guarantee; (ii) we find that the Java language is more restrictive—despite the claims in the specification, the Java Memory Model does not allow some important program transformations, such as common subexpression elimination. To establish the safety results, we develop a trace semantic framework and describe important program optimisations as relations on sets of traces. We prove that all our elimination and reordering transformations satisfy the DRF guarantee, i.e., the semantic transformations cannot introduce new behaviours for data race free programs. Moreover, we prove that all the transformations preserve data race freedom. This ensures safety of transformations composed from eliminations and reorderings. In addition to the DRF guarantee, we prove that for arbitrary programs, our transformations prevent values appearing “outof- thin-air”—if a program does not contain constant c and does not perform any operation that could create c, then no transformation of the program can output c. We give an application of the semantic framework to a concrete language and prove safety of several simple syntactic transformations. We employ similar semantic techniques to prove validity of several classes of transformations, such as the elimination of an overwritten write or reordering of independent memory accesses, in the Java Memory Model. To establish the iii negative results for the Java Memory Model, we provide counterexamples showing that several common optimisations can introduce new behaviours and thus are not safe.

CEJN is a leading transnational company with long history and professional background providing high-tech quick connect products in global market. The headquarters of the com-pany in Skövde, Sweden, is the birthplace and core location of the entire corporation. In the headquarters, the engineer tests their products at their flow test laboratory. In the laboratory, there are flow test stations for all product ranges. Within them, the most basic are flow test benches for air, water and hydraulic oil products. The flow test benches are aim to test the products under International/Swedish standard conditions to determine the performance. This project is aimed in upgrading the test benches by engineering both hardware and soft-ware, to achieve higher level of automation of the data logging system used in the lab. All three test benches were designed and installed following requirements in corresponding in-ternational standards. The principles of testing are similar, but they are not developed from the same era, and the automation level of each test bench differs. As a result, the need of up-grading in the benches is different. In the laboratory, the recorded test results are reorganized and processed by a report genera-tor developed on Microsoft Excel. The Excel report generator is used for organize test results, calibrate the deviation of the instruments, calculate the flow coefficient of the product, gener-ate performance diagrams of the products, generate test reports for different purpose of use, and save the test data and results on the server of the company. Above all, an upgrade of the data logging system for the three flow test benches was needed. Depending on the conditions of each test bench, the project is implemented and designed the following three parts: • A hardware upgrading (flow rate computer) for the air flow test benchA new signal indicating device for replacing the old flow rate computer is purchased from Italy by the company. The new instrument contains filter function to stabilize the flow rate value. • A software upgrading (Excel report generator) for all the test benchesVisual Basic for Applications (VBA) programming language is used for developing functions such as data communication, signal decoding and user interface developing in Excel. • Develop of an automated data visualizing system for the air flow test benchData communication from the new instrument to a PC through serial port and Mod-bus RTU interface is established. The data visualizing function is compiled in the Ex-cel report generator for the air flow test, realized by VBA programming.

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The problem of this study was to determine what are the maintenance practices and to what extent are they being used by industrial arts teachers in the subject areas of woodworking, metalworking, and drafting at the secondary level in the state of Texas.

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Innovation laboratories are environments especially designed for carrying out the innovation process. They are an example of a new kind of organisational structure that has emerged as a managerial response to challenges associated with organisational dynamic capability development. Using a mixed-method approach, this thesis attempts to create an understanding for the challenges and opportunities that exist in the management of an innovation laboratory, both on a level of organisational innovation and of individual creativity. The componential model of creativity and innovation in organisations is used as a framework for analysis of an innovation laboratory in the case company, the tech consultancy firm Semcon. The results confirm that there is a lack of clarity in the conceptualisation of innovation labs. Some important findings are that the implementation of an innovation laboratory could in itself be seen as an opportunity, but that acting in the borderland between the objectives of profitability and creativity could prove a challenge. A challenge may also lie in maintaining a realistic view of the actual abilities of the innovation laboratory. Cross-functional collaboration between consultants seems to bring opportunities in that it may contribute to knowledge creation and transfer within the firm, but there is a challenge in that teams are in need of leaders with skills in creativity management and agile project management, but also technical expertise. A general conclusion for managing innovation laboratories is that they need enough resources to have room for mistakes. The findings have implications for the management of existing innovation laboratories and those in the planning.

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