In dieser Dissertation wird das Skalenverhalten derÜbergangstemperatur von Systemen an diskontinuierlichen Phasenübergängen aus einem Zwei- Zustands-Modell abgeleitet und erweitert. Es wird erläutert, wie sich das Skalenverhalten für periodische Randbedingungen drastisch verändern kann, sobald der Entartungsgrad der geordneten Phasen von der Teilchenzahl abhängt. Eswerden Modellsysteme in zwei und drei Dimensionen betrachtet, deren Zustandssummen mittels analytischer, kombinatorischer Argumente berechnet werden. Für das kompliziertere, isotrope Plaquettemodell in drei Dimensionen können durch diese Rechnungen Ordnungsparameter definiert werden. Diese werden, zusammen mit dem veränderten Skalenverhalten selbskonsistent durch anspruchsvolle und hochpräzise, sogenannte multikanonische Monte-Carlo Simulationen überprüft und bestätigt.

Development of software for electronic systems in the aviation industry is strongly regulated by pre-defined standards. The aviation industry spends significant costs of development in ensuring flight safety and showing conformance to these standards. Some safety requirements can be satisfied by performing formal verification. Formal verification is seen as a way to reduce costs of showing conformance of software with the requirements or formal specifications. Therefore, the correctness of formal specifications is critical. Writing formal specifications is at least as difficult as developing software [36]. This work proposes an approach to generate formal specifications from example data. This example data illustrates the natural language requirements and represents the ground truth about the system. This work eases the task of an engineer who has to write formal specifications by allowing the engineer to specify the example data instead. The use of a relationship model and a marking syntax and semantics are proposed that make the creation of formal specifications goal oriented. The evaluation of the approach shows that the proposed syntax and semantics capture more information than is strictly needed to generate formal specifications. The relationship model reduces the computational load and only produces formal specifications that are interesting for the engineer.

New magnetocaloric Heusler alloys with larger magnetocaloric effects need to function in relatively low applied magnetic fields ≤ 1 T. Therefore, the emphasis of this Ph.D. thesis was to understand how the first order magnetostructural transformation in Mn-rich Ni-based rare-earth free magnetocaloric Heusler alloys works and to use this understanding for the design of new Mn-rich Ni-based rare-earth free magnetocaloric Heusler alloys. In this context, the rare-earth free, non-toxic, and environmentally friendly Heusler series: Ni2−xMn1+xSn, Mn50Ni50−ySny, and Ni-(Co-)Mn-In were systematically studied. In detail, it pointed out that in the Heusler series Ni2−xMn1+xSn, the structure and the disorder character can be predicted by using simple rules. On the other hand, an isoplethal section of the Heusler series Mn50Ni50−ySny was derived, which is very useful for the design of new magnetocaloric materials. In addition to it, in the Heusler alloy Ni49.9Mn34.5In15.6 a large saturated magnetic moment and a reversible magnetocaloric effect at its purely second order magnetic phase transition was present, which is in reasonable agreement with ab initio calculations. Finally, the effect of post-annealing on the Heusler alloy Ni45.2Co5.1Mn36.7In13 revealed that the magnetocaloric effect could be tuned and improved significantly. Consequently, this work shows that the Heusler alloys are promising candidates for magnetocaloric applications.

There have been numerous studies on formal methods but little utilisation of formal methods in the commercial world. This can be attributed to many factors, such as that few specialists know how to use formal methods. Moreover, the use of mathematical notation leads to the perception that formal methods are difficult. Formal methods can be described as system design methods by which complex computer systems are built using mathematical notation and logic. Formal methods have been used in the software development world since 1940, that is to say, from the earliest stage of computer development. To date, there has been a slow adoption of formal methods, which are mostly used for mission-critical projects in, for example, the military and the aviation industry. Researchers worldwide are conducting studies on formal methods, but the research mostly deals with path planning and control and not the runtime verification of autonomous systems. The main focus of this dissertation is the question of how to increase the pace at which formal methods are adopted in the business or commercial world. As part of this dissertation, a framework was developed to facilitate the use of formal methods in the commercial world. The framework mainly focuses on education, support tools, buy-in and remuneration. The framework was validated using a case study to illustrate its practicality. This dissertation also focuses on different types of formal methods and how they are used, as well as the link between formal methods and other software development techniques. An ERP system specification is presented in both natural language (informal) and formal notation, which demonstrates how a formal specification can be derived from an informal specification using the enhanced established strategy for constructing a Z specification as a guideline. Success stories of companies that are applying formal methods in the commercial world are also presented. / School of Computing

: leaves 122-134 / There have been numerous studies on formal methods but little utilisation of formal methods in the commercial world. This can be attributed to many factors, such as that few specialists know how to use formal methods. Moreover, the use of mathematical notation leads to the perception that formal methods are difficult. Formal methods can be described as system design methods by which complex computer systems are built using mathematical notation and logic. Formal methods have been used in the software development world since 1940, that is to say, from the earliest stage of computer development. To date, there has been a slow adoption of formal methods, which are mostly used for mission-critical projects in, for example, the military and the aviation industry. Researchers worldwide are conducting studies on formal methods, but the research mostly deals with path planning and control and not the runtime verification of autonomous systems. The main focus of this dissertation is the question of how to increase the pace at which formal methods are adopted in the business or commercial world. As part of this dissertation, a framework was developed to facilitate the use of formal methods in the commercial world. The framework mainly focuses on education, support tools, buy-in and remuneration. The framework was validated using a case study to illustrate its practicality. This dissertation also focuses on different types of formal methods and how they are used, as well as the link between formal methods and other software development techniques. An ERP system specification is presented in both natural language (informal) and formal notation, which demonstrates how a formal specification can be derived from an informal specification using the enhanced established strategy for constructing a Z specification as a guideline. Success stories of companies that are applying formal methods in the commercial world are also presented. / School of Computing / M. Sc. (Computing)

The aim of the thesis Applications of The Theory of Second-Order Elections to Elections in the Czech Republic is to answer the research question, whether is the theory fulfilled in the Czech Republic, through various hypotheses. The introduction introduces the intention of my research. The theoretical part deals with the original Theory of Second-order elections, which was introduced already in 1980 by authors Karlheinz Reif and Hermann Schmitt. During the next electoral cycles, the Theory of Second-order elections was more refined and reflected by other theoreticians, whose contribution is a source of inspiration for my theoretical part. Another major chapter presents the methodology and research design. This chapter defines hypotheses. The Thesis is trying to prove, or disprove the following hypotheses. Electoral participation in the case of Second-order elections is lower than in the case of the First-order elections. The Second-order elections tend to punish ruling parties. Political parties that currently govern, gets in case of Second-order elections less votes. Governmental parties lose the most electoral support in the middle of their term and it turns out the influence of the electoral cycle. Small political subjects have a greater chance of success during the Second-order elections than...

Organic matter (OM) is often considered the “currency” for ecosystem processes, such as respiration and primary production. OM in aquatic ecosystems is derived from multiple sources, and is a complex mixture of thousands of different chemical constituents. Therefore, it is difficult to identify all the sources of OM that enter and exit aquatic ecosystems. As humans develop undisturbed land, the rate at which terrestrial OM (e.g.soil and plants) and associated nutrients (e.g.nitrogen) enters rivers has increased. Increased nutrients may lead to increased primary production from aquatic plants and algae, potentially causing eutrophication and harmful algal blooms. In this study, I identified and characterized different sources of OM in four watersheds of Northeastern Utah with multiple land covers such as cities, forests, and crops. I expected OM in watersheds with human-altered land cover would have more OM produced instream by algae and other primary producers, than OM in less disturbed watersheds, which typically have OM from terrestrial sources. I found that OM at river sites with high human impact had high amounts of OM from instream primary production, but there was also OM produced in-steam at sites with low human impact. The greatest differences in OM across watersheds was due to wastewater treatment effluent. I also measured microbial consumption rates of algal derived and terrestrially derived DOM in experimental streams to quantify how much faster algal derived OM was consumed than terrestrial OM. I found algal derived OM was consumed extremely fast, so fast that realistic measurements of its consumption in some river ecosystems may not be possible. It is important to identify and characterize sources of OM to rivers, so watershed manager scan devise effective OM reduction plans appropriate for the constituent of concern unique to that watershed or region. Constituents of concern associated with OM include pathogens affiliated with manure, toxins in harmful algal blooms, metals, and pharmaceuticals from wastewater treatment effluent. Each pollutant requires a unique mitigation strategy and therefore the first step to pollution mitigation is source identification.

There is a lot of demand from society or the government to incorporate ICT into preschool and education in general. However, no research in this area has been found that specifically cites technology's capacity to address concerns connected to planning, and systematic quality work in the preschool context. Technology integration, on the other hand, has ramifications for teachers, who face first- and second-order barriers to technological acceptance. In this study, we identify the determinants of technology acceptance among preschool teachers in Sweden. This study follows a mixed-method approach that comprises 12 semi-structured interviews and a self-completion survey of 9 respondents. The qualitative results were analyzed by a thematic analysis process and the quantitative results with descriptive statistics. We identified that job relevance, external control,  result demonstrability, output quality and internal control are the main determinants that play a crucial role in technological acceptance. We also found the persistence of the first-order barrier to the acceptance of technology. This finding contradicts an earlier study where it was stated that the first-order barriers were decreasing in schools. It was, however, discovered that several first-order obstacles in the form of external control factors still exist. Furthermore, it was also found that social factors such as voluntariness, image and subjective norm did not play a crucial role in technology acceptance. Finally, our results show that the use of technology has helped teachers in the documentation and planning, as well as identify the benefits of systematic quality work.

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