Choice and chance:model-based testing of stochastic behaviour

Probability plays an important role in many computer applications. A vast number of algorithms, protocols and computation methods uses randomisation to achieve their goals. A crucial question then becomes whether such probabilistic systems work as intended. To investigate this, such systems are often subjected to a large number of well-designed test cases, that compare a observed behaviour to a requirements specification. Model-based testing is an innovative testing technique rooted in formal methods, that aims at automating this labour intense and often error-prone manual task. By providing faster and more thorough testing at lower cost, it has gained rapid popularity in industry and academia alike. However, classic model-based testing methods are insufficient when dealing with inherently stochastic systems. This thesis introduces a rigorous model-based testing framework, that is capable to automatically test such systems. The presented methods are capable of judging functional correctness, discrete probability choices, and hard and soft-real time constraints. The framework is constructed in a clear step-by-step approach. First, the model-based testing landscape is laid out, and related work is discussed. Next, we instantiate a model-based testing framework to highlight the purpose of individual theoretical components like, e.g., a conformance relation, test cases, and practical test generation algorithms. This framework is then conservatively extended by introducing discrete probability choices to the specification language. A last step further extends this probabilistic framework by adding hard and soft real time constraints. Classical functional correctness verdicts are thus extended with goodness of fit methods known from statistics. Proofs of the framework’s correctness are presented before its capabilities are exemplified by studying smaller scale case studies known from the literature. The framework reconciles non-deterministic and probabilistic choices in a fully-fledged way via the use of schedulers. Schedulers then become a subject worthy to study in their own rights. This is done in the second part of this thesis; we introduce a most natural equivalence relation based on schedulers for Markov automata, and compare its distinguishing power to notions of trace distributions and bisimulation relations. Lastly, the power of different scheduler classes of stochastic automata is investigated. We compare reachability probabilities of different schedulers by altering the information available to them. A hierarchy of scheduler classes is established, with the intent to reduce complexity of related problems by gaining near optimal results for smaller scheduler classes

Rise of the Planet of Serverless Computing: A Systematic Review

Serverless computing is an emerging cloud computing paradigm, being adopted to develop a wide range of software applications. It allows developers to focus on the application logic in the granularity of function, thereby freeing developers from tedious and error-prone infrastructure management. Meanwhile, its unique characteristic poses new challenges to the development and deployment of serverless-based applications. To tackle these challenges, enormous research efforts have been devoted. This paper provides a comprehensive literature review to characterize the current research state of serverless computing. Specifically, this paper covers 164 papers on 17 research directions of serverless computing, including performance optimization, programming framework, application migration, multi-cloud development, testing and debugging, etc. It also derives research trends, focus, and commonly-used platforms for serverless computing, as well as promising research opportunities

Finding fun:characteristics of non-formal technology education in Oulu

Abstract. Education is not a singular, straight line from kindergarten to a diploma anymore for everyone. It is important to know and acknowledge the different types of out-of-school learning experiences young people can embark on in the quest for mastering a trade or just to have a good time. In this exploratory study into the world of non-formal technology education in the area of Oulu, Finland two different instances of varying levels of non-formality were investigated and how participants find fun in these situations since it is apparent that if something is non-mandatory to attend to, there should be some type of enjoyment found in the process. Tiedekoulu and Koodikärpät-kerho are clubs geared towards children and teens that have interest in playing with, making and programming technology. The observations with field notes were done in five different types of programming clubs and three different robotics ones with interviews that were conducted with 10 participants (ages 8–17), 6 parents and 6 instructors from these clubs. From the previous literature the practices and qualities of non-formal education could be defined, what fun is and how it manifests in children while they attend pedagogical situations. From this framework, the results of the analysis suggest that there are three main ways children and teenagers have fun in non-formal education: fun from the tasks they are doing, social fun by sharing with other attendants and pedagogical fun with instructors. Some attributes of the observed clubs were categorized as well along the lines of formal/non-formal/informal and the practices of the clubs were explored. Besides these findings, the limitations and implications for future research were also looked at

Stakeholder perceptions : the impact of a university-based laboratory school on a campus-based university educator preparation program

Field of study: Educational leadership and policy analysis.Dr. Carole Edmonds, Dissertation Supervisor.Includes vita."May 2018."A gap in research on the impact of a university-based laboratory school on a campus-based educator preparation program and a decrease in the number of university-based laboratory schools requires current laboratory school programs to evaluate strengths and weaknesses to provide quality evaluative data to ensure continued viability. This qualitative study sought to expand the extant research by identifying perceptions of stakeholders, educator preparation program students, faculty, administrators, and laboratory school teachers, parents, and administrators--to examine the impact of a laboratory school on an educator preparation program. The case study outlined stakeholder perceptions at one university and one laboratory school and investigated the perceptions of stakeholders regarding the impact of a university-based laboratory school to a campus-based educator preparation program. Four major themes emerged related to the impact of a laboratory school on an educator preparation program include: experimentation, early practice and ability to bridge theory to practice, expertise of faculty and teachers, and safety and support of environment to practice new learning. A fifth overarching theme was identified as significant to research: complexity of the organization.Includes bibliographical references (pages 131-144)

From The Top: Impression Management Strategies And Organizational Identity In Executive-authored Weblogs

This research examines impression management strategies high-ranking organizational executives employ to create an identity for themselves and their companies via executive authored Weblogs (blogs). This study attempts to identify specific patterns of impression management strategies through a deductive content analysis applying Jones’ (1990) taxonomy of self-presentation strategies to this particular type of computer mediated communication. Sampling for this study (n=227) was limited to blogs solely and regularly authored by the highest-ranking leaders of Fortune 500 companies. The study revealed that executive bloggers frequently employed impression management strategies aimed at currying competency attributes (self-promotion), likeability (ingratiation), and moral worthiness (exemplification) to construct and shape a positive identify for themselves and their organization for their publics. Supplication strategies were used less frequently, while intimidation strategies were rarely used