Model checking is a formal verification technique for verifying temporal properties in state-transition models. The main problem with using model checking is the state explosion problem, where the number of states in the model can grow exponentially, making verification infeasible. Previous work has tried to mitigate the state explosion problem by representing code blocks as Hoare-logic contracts in an abstract state-transition model using the temporal logic TLA. This is achieved by treating the block as atomic. In order to ensure that the abstract state-transition model is faithful with respect to the temporal properties you want to verify, only some code blocks can be considered atomic. This thesis aims to answer how atomic code blocks can be identified atomically and evaluate their potential for reducing state space during model checking. We give a theoretical foundation of what it means for a code block to be considered as atomic in TLA. Moreover, we introduce a property that characterizes these atomic code blocks and presents an algorithm to identify them for sequential programs written in a subset of C. Experimental results demonstrate that the identification of atomic code blocks using our algorithm can be used to significantly reduce the state space during model checking, with an average reduction factor of 62. The potential of this verification approach is promising, however, further case studies are necessary to better understand the extent of this reduction across different program types and properties. / Modellkontroll är en formell verifieringsteknik för att bekräfta tidsrelaterade egenskaper i tillståndsövergångsmodeller. Huvudproblemet med modellkontroll är problemet med tillståndsexplosion, där antalet tillstånd i modellen kan öka exponentiellt och göra verifieringen ogenomförbar. Tidigare arbete har försökt mildra problemet med tillståndsexplosion genom att representera kodblock som Hoare-logiska kontrakt i en abstrakt tillståndsövergångsmodell med hjälp av tidslogiken TLA. Detta uppnås genom att behandla blocket som atomiskt. För att säkerställa att den abstrakta tillståndsövergångsmodellen är trogen med avseende på de tidsrelaterade egenskaper du vill verifiera kan endast vissa kodblock betraktas som atomiska. Denna avhandling syftar till att besvara hur atomiska kodblock kan identifieras automatiskt och utvärdera deras potential för att minska tillståndsutrymmet under modellkontroll. Vi ger en teoretisk grund för vad det innebär för ett kodblock att betraktas som atomiskt inom TLA. Dessutom introducerar vi en egenskap som karaktäriserar dessa atomiska kodblock och presenterar en algoritm för att identifiera dem för sekventiella program skrivna i en delmängd av C. Experimentella resultat visar att identifieringen av atomiska kodblock med hjälp av vår algoritm kan användas för att betydligt minska tillståndsutrymmet under modellkontroll, med en genomsnittlig reduktionsfaktor på 62. Potentialen för denna verifieringsmetod är lovande, men ytterligare fallstudier krävs för att bättre förstå omfattningen av denna reduktion över olika typer av program och egenskaper.

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This degree project’s purpose is to gain some insight into what advantages and disadvantages on teaching and learning a TL exist in multilingual classrooms, as well as what impact these outcomes might have on teachers’ pedagogical choices. The paper provides an overview of theories relating to language learning and third language learning, as well as the research. Researchers contend that teachers should maximize the TL use in the classroom, however there currently exists a dispute about whether the L1 should be used as a resource in the TL classroom or not. The study is conducted through interviews with four active English teachers, in the south of Sweden. The major conclusions of this paper are that L3 learners can have an advantage when learning a TL, and that the presence of L3 learners can have a positive effect on the motivation of the L2 learner classmates with regard to learning the TL. A discrepancy exists between how research and the national curriculum encourage teachers to teach and how they actually do in their pedagogical practice. The paper identifies a possible explanation for this discrepancy, as well as possible implications of it.

With the widely use of software technique in everyday applications, the correctness of software becomes more and more important. Formal verification is an important method to improve the correctness of software. However, it mainly takes formal languages as its modeling languages, which are based on mathematical logic, automata or graph theory, hard for learning and domain description. That hinders the applications of formal verification in industry. This dissertation investigates the design and practice of domain modeling and verification language EDOLA, to possess all the features of the usability for domain description, reusability and automatic verification. It proposes a three-level design method with the domain knowledge level, the common module level and the verification support level. The main contributions are summarized as follows: 1. In the domain knowledge level, the extraction and representation methods of the domain knowledge on both job-shop scheduling and PLC control software are proposed. It defines domain-specific operators of the job-shop scheduling problem, timed Petri net, etc. for the job-shop scheduling description. It also defines the operators of the scan cycle pattern, the complete environment pattern and five kinds of verification requests for the PLC domain description. It presents the formal semantics of the defined domain-specific operators, for the further EDOLA definition and its automatic verification. 2. In the common module level, the method to define common operators is presented with real-time as an example for common knowledge. It proposes two kinds of basic time operators and four advanced ones, which help EDOLA to describe real-time features easily and make the reusability of EDOLA design among time-sensitive domains possible. 3. In the verification support level, it presents a properties-oriented abstraction strategy, which reduces the state space and exploring space during automatic verifi- cation. It then formulates the encoding rules from EDOLA to first-order logic, thus implements the verification of the models with infinite states, with the help of first-order logic automatic theorem provers. 4. A prototype of the PLC domain modeling and verification language: EDOLA-PLC are developed and its tools are implemented. The tools provide an EDOLA-PLC editor and a compiler with the functionalities like syntax checking, semantics checking and translation-based automatic verification. 5. A case study of the EDOLA-PLC language on a dock fire-fighting control system is presented. It indicates that EDOLA-PLC is easy to describe both the PLC domain knowledge and the properties to be verified; is easy to describe the common knowledge: real-time and can be verified automatically. The results show that the abstraction strategy adopted in the verification support level of EDOLA-PLC improves the efficiency of automatic verification.

The aim of this dissertation is to critically explore elements of comedy and satiric elements in two television dramas of D.M. Mothibi, / African Languages / M.A. (African Languages)

In the present study, the influence of morphosyntactic aspects of L1 and L2 on L3 comprehension is investigated using ERP (Event-Related Brain Potentials). The study examines the processing of verb and gender agreement incongruences in Spanish by native Swedish speakers that are fluent in English and learning Spanish, in comparison to a control group of native Spanish speakers. The study investigates the relevance of morphosyntactic transfer from L1 and/or L2 to L3, as well as language processing in third language acquisition. Language acquisition is considered as an individual process, different in acquisition of the first, second and third language. EEG (Electrocephalograpy) had been used in the present study to examine the processing of verb and gender agreement. Different views on L3 learning have been shown in previous studies according to whether L1 or L2 have a stronger influence on the acquisition of L3. Regarding native like processing of language, the study showed that L3 learners process language differently in comparison with native like speakers. In particular, adjective agreement engender a specific brain reaction (a P300) in L3 learners only and not in L1 speakers. Verb agreement, on the other hand, do not engender the P300 in any of the of the groups. The P300 effect is related to strategic processing of language, which leads to the possibility of considering that the morphosyntactic transfer of their first language (Swedish) to the third language is processed in a less automatic mode than L2 (English).

(in English) This diploma thesis focuses on teachers' attitudes and beliefs regarding English grammar teaching at Czech high schools. The thesis is based on the assumption that teachers' decisions and actions in ESL and EFL teaching are motivated by what teachers know, think and believe. It takes the concept of teacher cognition as a starting point. The research part ot the thesis is based on a questionnaire survey among Czech high-school teachers. It aims to observe teachers' beliefs about English grammar teaching and learning and to describe the way Engligh grammar is taught at Czech high schools. The main areas which the research focuses on are grammar teaching approaches, grammar practice, grammatical error correction, the use of L1 in teaching grammar and the use of coursebooks. Moreover, the thesis observes teachers' position towards the concept of method with respect to the recent trend discussed in ELT research - the post-method condition which redefines the relationship of 'method' and a teacher who is understood as a critical and creative strategic thinker.

Sustainable Built Environments Senior Capstone / The purpose of this paper is to provide basic empirical evidence to support the implementation of an innovation campus in downtown Tucson. This would be a satellite of the Arizona Center for Innovation (AZCI) currently located in the University of Arizona Science and Technology Park – an innovation, research and business center on the outskirts of Tucson. A multi-case study analysis will be performed where the results will be compared with that of the AZCI results, using the same criteria.

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)