Software maintenance is such an integral part of its evolutionary process that it consumes much of the total resources available. Some estimate the costs of maintenance to be up to 100 times the amount of developing a software. A software not maintained builds up technical debt, and not paying off that debt timely will eventually outweigh the value of the software, if no countermeasures are undertaken. A software must adapt to changes in its environment, or to new and changed requirements. It must further receive corrections for emerging faults and vulnerabilities. Constant maintenance can prepare a software for the accommodation of future changes.

While there may be plenty of rationale for future changes, the reasons behind historical changes may not be accessible longer. Understanding change in software evolution provides valuable insights into, e.g., the quality of a project, or aspects of the underlying development process. These are worth exploiting, for, e.g., fault prediction, managing the composition of the development team, or for effort estimation models. The size of software is a metric often used in such models, yet it is not well-defined. In this thesis, we seek to establish a robust, versatile and computationally cheap metric, that quantifies the size of changes made during maintenance. We operationalize this new metric and exploit it for automated and efficient commit classification.

Our results show that the density of a commit, that is, the ratio between its net- and gross-size, is a metric that can replace other, more expensive metrics in existing classification models. Models using this metric represent the current state of the art in automatic commit classification. The density provides a more fine-grained and detailed insight into the types of maintenance activities in a software project.

Additional properties of commits, such as their relation or intermediate sojourn-times, have not been previously exploited for improved classification of changes. We reason about the potential of these, and suggest and implement dependent mixture- and Bayesian models that exploit joint conditional densities, models that each have their own trade-offs with regard to computational cost and complexity, and prediction accuracy. Such models can outperform well-established classifiers, such as Gradient Boosting Machines.

All of our empirical evaluation comprise large datasets, software and experiments, all of which we have published alongside the results as open-access. We have reused, extended and created datasets, and released software packages for change detection and Bayesian models used for all of the studies conducted.

Software quality becomes more critical as our dependence on software increases. We need better quality assessment than ever. Comparison and ranking of software artifacts, detection of bad or good quality are important tasks for quality assessment.

Software quality models are widely used to support quality assessment. In general, they have a hierarchical structure and defines quality in terms of sub-qualities and metrics in a tree-like structure. Different metrics evaluate different quality criteria, and several metrics often needs to be assessed and aggregated to obtain a total quality score. The quality models standards of today do not enable numerical metrics aggregation. They leave aggregation to decision makers, and different methods of aggregation lead to different assessment results and interpretations. Hence, there is a need to define metrics aggregation formally based on well-known theories.

We propose to consider the probabilistic nature of quality as a solution. We consider metrics as random variables and define quality scores based on joint probabilities. The aggregation, and the quality model in extension, express quality as the probability of detecting something with equal or worse quality, based on all software projects observed; good and bad quality is expressed in terms of lower and higher probabilities. We analyze metrics dependencies using Bayesian networks and define quality models as directed acyclic graphs. Nodes correspond to metrics, and edges indicate dependencies. We propose an implementation using multi-threading to improve the efficiency of joint probabilities computations.

We validate our approach theoretically and in an empirical study on software quality assessment of approximately 100\,000 real-world software artifacts with approximately 4\,000\,000 measurements in total. The results show that our approach gives likely results and scales in performance to large projects.

We also applied our approach to a multi-criteria decision-making task to propose a ranking method to aid evaluation processes. We use a real-world funding allocation problem for a call that attracted approximately 600 applications to evaluate our approach. We compared our approach with the traditional weighted sum aggregation model and found that ranks are similar between the two methods, but our approach provides a more sound basis for a fair assessment.

Further, we implemented an exploratory multivariate data visualization tool, which visualizes the similarities between software artifacts based on joint distributions. We illustrate the usability of our tool with two case studies of real-world examples: a set of technical documents and an open source project written in Java.

Our overall results show that our approach for multi-criteria quality scoring is well-defined, has a clear interpretation, and is applicable under realistic conditions, generalizable, and transferable to other domains.

The latest developments of mobile devices include a variety of hardware features that allow for more rich data collection and services. Numerous sensors, Internet connectivity, low energy Bluetooth connectivity to other devices (e.g., smart watches, activity tracker, health data monitoring devices) are just some examples of hardware that helps to provide additional information that can be beneficially used for many application domains. Among others, they could be utilized in mobile learning scenarios (for data collection in science education, field trips), in mobile health scenarios (for health data collection and monitoring the health state of patients, changes in health conditions and/or detection of emergency situations), and in personalized recommender systems. This information captures the current context situation of the user that could help to make mobile applications more personalized and deliver a better user experience. Moreover, the context related information collected by the mobile device and the different applications can be enriched by using additional external information sources (e.g., Web Service APIs), which help to describe the user’s context situation in more details.

The main challenge in context modeling is the lack of generalization at the core of the model, as most of the existing context models depend on particular application domains or scenarios. We tackle this challenge by conceptualizing and designing a rich generic context model. In this thesis, we present the state of the art of recent approaches used for context modeling and introduce a rich context model as an approach for modeling context in a domain-independent way. Additionally, we investigate whether context information can enhance existing mobile applications by making them sensible to the user’s current situation. We demonstrate the reusability and flexibility of the rich context model in a several case studies. The main contributions of this thesis are: (1) an overview of recent, existing research in context modeling for different application domains; (2) a theoretical foundation of the proposed approach for modeling context in a domain-independent way; (3) several case studies in different mobile application domains.

Efficient design of high-voltage power cables is important to achieve an economical delivery of electric power from wind farms and power plants over the very long distances as well as the overseas electric power. The main focus of this thesis is the investigation of electromagnetic losses in components of high-voltage power cables. The objective of the ongoing research is to develop the theory and optimization techniques as tools to make material choices and geometry designs to minimize the high-frequency attenuation and dispersion for HVDC power cables and the power losses associated with HVAC cables. Physical limitations, dispersion relationships and the application of sum rules as well as convex optimization will be investigated to obtain adequate physical insight and a priori modeling information for these problems.

For HVAC power cables, the objectives are addressed by performing measurements and estimation of complex valued permeability of cable armour steel in Papers I and II. Efficient analytical solutions for the electromagnetic field generated by helical structures with applications for HVAC power cables have been obtained in Paper III.

For HVDC power cables, estimation of insulation characteristics from dielectric spectroscopy data using Herglotz functions, convex optimization and B-splines, has been investigated in Papers V and VI. The unique solution requirements in waveguide problems have been reviewed in Paper IV.

An increased share of construction with timber is one possible way of achieving more sustainable and energy-efficient life cycles of buildings. The main reason is that wood is a renewable material and buildings require a large amount of resources. Timber buildings taller than two storeys were prohibited in Europe until the 1990s due to fire regulations. In 1994, this prohibition was removed in Sweden.

    Some of the early multi-storey timber buildings were associated with more complaints due to impact sound than concrete buildings with the same measured impact sound class rating. Research in later years has shown that the frequency range used for rating has not been sufficiently low in order to include all the sound characteristics that are important for subjective perception of impact sound in light weight timber buildings. The AkuLite project showed that the frequency range has to be extended down to 20 Hz in order to give a good quality of the rating. This low frequency range of interest requires a need for knowledge of the sound field distribution, how to best measure the sound, how to predict the sound transmission levels and how to correlate numerical predictions with measurements.

    Here, the goal is to improve the knowledge and methodology concerning measurements and predictions of low frequency impact sound in light weight timber buildings. Impact sound fields are determined by grid measurements in rooms within timber buildings with different designs of their joist floors. The measurements are used to increase the understanding of impact sound and to benchmark different field measurement methods. By estimating transfer functions, from impact forces to vibrations and then sound pressures in receiving rooms, from vibrational test data, improved possibilities to correlate the experimental results to numerical simulations are achieved. A number of excitation devices are compared experimentally to evaluate different characteristics of the test data achieved. Further, comparisons between a timber based hybrid joist floor and a modern concrete floor are made using FE-models to evaluate how stiffness and surface mass parameters affect the impact sound transfer and the radiation.

    The measurements of sound fields show that light weight timber floors in small rooms tend to have their highest sound levels in the low frequency region, where the modes are well separated, and that the highest levels even can occur below the frequency of the first room mode of the air. In rooms with excitation from the floor above, the highest levels tend to occur at the floor levels and in the floor corners, if the excitation is made in the middle of the room above. Due to nonlinearities, the excitation levels may affect the transfer function in low frequencies which was shown in an experimental study. Surface mass and bending stiffness of floor systems are shown, by simulations, to be important for the amount of sound radiated.

    By applying a transfer function methodology, measuring the excitation forces as well as the responses, improvements of correlation analyses between measurements and simulations can be achieved

The gradually changing behavior of the population, towards urbanization, ledto an increased shortage of available housing. This development has resultedin a serious issue in Sweden, where too few firms are providing solutions formulti-family houses in wood. Potential firms that could fill this increasingdemand are those in the single-family house industry. Yet, these firms mightface considerable problems with productivity, predominately derived fromincreasing production costs and inadequate production development.Developing these firms are associated with long-term investments, whichis investigated by evaluating the industry structure for sellers, highlightingthe financial and market situation within their industry. These factors aregrowing in importance due to the current market concentration, where morefirms are required to focus on product development driven by the demand toprefabricate wooden elements, volumes or modules in an industrialized way.This thesis studies Swedish firms producing wooden single-familyhouses, with the aim to investigate their possibilities to enter the woodenmulti-family house industry in Sweden.Investigations will be conducted by applying Altman’s Z’ value, riskposition model, the Herfindahl-Hirschman index, the Herfindahl-Hirschmannumber equivalent, productivity ratio model for profitability and finally amodel measuring market Concentration Ratio.Results show that the industry tends towards perfect competition with toomany firms involved, i.e. firms mainly have to compete by prices. Further,firms are grouped into three zones; risk, grey or safe zone. The levels withinthese zone show a reduction of firms in the red zone over time. Related to thecurrent risks, many firms have promising positions to invest in productdevelopment towards wooden multi-family houses, in addition to theircurrent products, even though firm productivity has declined during thestudied time frame. The results that the investigated firms have goodpossibilities gaining a competitive advantage by diversifying into thegrowing wooden multi-family house industry.

Students often voice that the programming assignments are hard and that they spend a lot of time on solving them. Is this true; are we giving them too hard assignments and how much and what do they spend the time on? This is what we want to gain insight to. We constructed a tool that records programming sessions with finer granularity than the existing solutions. The tool has recorded 2643 programming sessions from students. Using that data we found that students spend only 15% of their time writing code, and that on average 40% of their programming effort is spent reading and navigating. We also estimate the time spent outside of the tool to be almost 20%. The increased detail in the recordings can be used to measure the effect of programming source code comments, and we found that the effect of both helpful and redundant comments increases the reading time but did not help to reduce the students writing effort. Finally, we used the tool to examine the effects of an improved programming assignment and found that the total effort was not reduced.

The fossil hydrocarbons are not inexhaustible, and their use is not without impact in our need of energy, fuels and hydrocarbons as building blocks for organic materials. The quest for renewable, environmentally more friendly technologies are in need and woody biomass is a promising candidate, well provided in the boreal parts of the world. To convert the constituents of wood into valuable gaseous products, suitable for the end use required, we need a reliable gasification technology. But to become an industrial application on full scale there are still a few issues to take into account since the presence of contaminants in the process gas will pose several issues, both technical and operational, for instance by corrosion, fouling and catalyst deactivation. Furthermore the downstream applications may have very stringent needs for syngas cleanliness depending on its use. Therefore, the levels of contaminants must be decreased by gas cleanup to fulfil the requirements of the downstream applications.

One of the most prominent problems in biomass gasification is the formation of tars – an organic byproduct in the degradation of larger hydrocarbons. So, tar degrading catalysts are needed in order to avoid tar related operational problems such as fouling but also reduced conversion efficiency. Deactivation of catalysts is generally inevitable, but the process may be slowed or even prevented. Catalysts are often very sensitive to poisonous compounds in the process gas, but also to the harsh conditions in the gasifier, risking problems as coke formation and attrition. Alongside with having to be resistant to any physical and chemical damage, the catalyst also needs to have high selectivity and conversion rate, which would result in a more or less tar-free gas. Commercial tar reforming catalysts of today often contain nickel as the active element, but also often display a moderate to rapid deactivation due to the causes mentioned.

Patterns are a source of knowledge when architecting software systems. They provide abstract and time-tested solutions that show how a system should be structured to achieve needed qualities. However, when developing software there is a chance that small mistakes are introduced in the source code. Over time, these mistakes can accumulate and break the structure of the pattern and its qualities are lost. There are methods that can help find such errors, but none of these provide a pattern abstraction. In this work, we describe a method that raises the level of abstraction from checking individual dependencies to checking key dependencies in the pattern. We implement our method, apply it to check the Model-View-Controller pattern. We show that the method can find architectural problems in real source code and examine how removal of detected erosions affects the source code. We conducted an experiment in a software project setting to determine if using the method affects the number of architectural problems. Some project teams were randomly assigned to use a software service that automated our method. It checked how well their implementation conformed to Model-View-Controller every time they updated the source code. The experiment showed that developers that used the tool had significantly fewer detected architectural problems during the course of the project. Our method makes conformance checking easier to use. This might help increase the adoption of conformance checking in industry.

In three studies of a cruise ship the author has investigated waste heat recovery (WHR)from exhaust gases using an organic Rankine cycle (ORC), and also mapped the energyand exergy flows within the ship. Data were collected from the ship’s machinerysystem for a total extent of one year, and this data were used for simulations andenergy calculations. An off-design analysis was made and an ORC was simulated andoptimised with regards to the ship’s operating conditions. The ORC working fluid wasoptimised in terms for maximum electrical production in the off-design condition. Theoff-design analysis showed that the ship speed and power consumption was far fromits original design. The results indicate that there is a potential for significant savingsby using an organic Rankine cycle for waste heat recovery. The energy and exergyanalysis gave a better understanding of the energy flows and showed that the singlelargest exergy destruction occurs in the ship’s diesel engines.

Increased interaction between scientists and the social environment is considered to be one of the characteristics of modern science. This interaction can occur through collaboration between different sectors in society. In connection to this, the Triple Helix model claims that interaction between university, industry and public sectors, is key to modern innovation development. So far, cross-sector interaction between actors in environmental science has been scarcely studied in a scientific manner. Most studies carried out in the area have disregarded the actual practice of such collaborations and what happens in projects where these sectors interact. As this has become a common way to solve environmental problems, it is of considerable importance to gain more knowledge about this process. The objective of this research was to study and explain cross-sector collaboration. Using the interactive research method, characterised by joint learning and interaction with the participants, this was explored through two case studies. The method was well suited for studying ongoing interactions between the university, industry and public sectors. The first case was an international collaboration between representatives of the Triple Helix sectors. Here, olive-mill wastewater in Greece was the focus. The Triple Helix framework was used both on the intended analytical level and at a management level closer to the actor level of the participants. The second case was a three-year environmental research project in the Kalmar region where strong university-industry collaboration was carried out in order to find wastewater treatment solutions in the wood industry. This collaboration was extended to include more actors in the region during the process. The actual practice of these cases showed the importance of a dialogue between participants. Triple Helix can be used as an initial framework for such a dialogue through which the model is redefined by input from all sectors.

Children´s and young people´s images of the police

                   - a study in two local contexts

Abstract

This licentiate thesis focuses on children´s and young people´s images of the police. The aim is to describe and analyze these images and place them in late modernity. The starting point is taken in a notion that images are socially constructed, based on structures of power, habitus, social positions and a symbolic capital. To understand the importance of what meaning young people put into the police, the approach also is influenced by cultural sociology.

Data were collected through a questionnaire to 1 945 children and young people, aged 10-22 years with no specific criminal experiences, in two local contexts; Karlskrona and Landskrona, two municipalities in the Southern part of Sweden. Conversational interviews were conducted in group sessions with in all 50 children and young people. The quantitative material, processed in SPSS, is used in a descriptive manner. For the interviews, a thematic analysis method was used. Regarding the participants’ images three main themes emerged; conceptions, experiences and expectations.

Findings show that these children and young people have positive thoughts about the police as an institution but are to some extent more critical with regard to the police as an organization and far more critical when it comes to individual police officers. Almost all the participants have been in contact with police officers, mostly in school or when they have applied for a passport. Regarding expectations they want the police to focus their efforts on adults.  The children, aged 10-12, are more positive about the police while the group of 13-16 year olds are more negative. To some extent the older group, aged 17-22, are more differentiated.

Furthermore, it appears that conceptions, experiences and expectations are closely linked. Conceptions are based on various experiences, which in turn generate various expectations in light of different circumstances in life. Some images are more generally occurring while others mainly are produced in groups of young people. Young people´s images can be interpreted as a struggle within the field where the habitus and symbolic capital constitutes a force. If we choose to look at young people as seismographs, their images can be signs of images of the police even among adults. Ultimately it turns out that there seems to be a mystique surrounding the police. For people it is exciting to see the police in action in real life while the police themselves are secretive about how they operate; which also may contribute to the images we create. And in this study it appears not to be differences worth mentioning between the two local contexts.

The purpose of this study is to improve our knowledge about teaching and learning of informal statistical inference. A qualitative research strategy is used in the study that focuses on the testing and generation of theories inspired by grounded theory. The knowledge focus of the study is aimed at the characterisation of statistical processes and concepts where systems of concept frameworks about informal statistical inference and modelling represent an essential part of the research. In order to obtain adequate empirical data, a teaching situation was devised whereby students were involved in planning and implementing an investigation. The study was conducted in a normal classroom situation where the teaching was focused on an area in probability and statistics that included the introduction of box plots and normal distribution with related concepts. The empirical material was collected through video recordings and written reports. The material was analysed using a combined framework of informal statistical inference and modelling. The results of the analysis highlight examples of how students can be expected to express aspects of informal statistical inference within the context of statistical inquiry. A framework was also developed aimed to theoretically depict informal statistical inference in modelling situations. The study suggests that this framework has the potential to be used to analyse how informal statistical inference of students are expressed and to identify potential learning opportunities for students to develop their ability to express inferences.

The work in this thesis is basically divided into two related but separate investigations.

The first part treats simple chemical reactions of adsorbate molecules on metallic surfaces, induced by means of a scanning tunneling probe (STM). The investigation serves as a parameter free extension to existing theories. The theoretical framework is based on a combination of density functional theory (DFT) and non-equilibrium Green's functions (NEGF). Tunneling electrons that pass the adsorbate molecule are assumed to heat up the molecule, and excite vibrations that directly correspond to the reaction coordinate. The theory is demonstrated for an OD molecule adsorbed on a bridge site on a Cu(110) surface, and critically compared to the corresponding experimental results. Both reaction rates and pathways are deduced, opening up the understanding of energy transfer between different configurational geometries, and suggests a deeper insight, and ultimately a higher control of the behaviour of adsorbate molecules on surfaces.

The second part describes a method to calculate STM images in the low bias regime in order to overcome the limitations of localized orbital DFT in the weak coupling limit, i.e., for large vacuum gaps between a tip and the adsorbate molecule. The theory is based on Bardeen's approach to tunneling, where the orbitals computed by DFT are used together with the single-particle Green's function formalism, to accurately describe the orbitals far away from the surface/tip. In particular, the theory successfully reproduces the experimentally well-observed characteristic dip in the tunneling current for a carbon monoxide (CO) molecule adsorbed on a Cu(111) surface. Constant height/current STM images provide direct comparisons to experiments, and from the developed method further insights into elastic tunneling are gained.

Mathematics teachers’ profession and professional development is essential to develop students’ learning. The aim of this study has been to follow a processin order to understand what and how mathematics teachers learn in a community of practice. A group of mathematics teachers grade 1-6 met regularly for a period of one year. This group, called the reflection group, was tasked with developing a common core question. The reflection group’s joint enterprise was to understand more about communication and reasoning in mathematics teaching. The study is based on Goodchild’s (2008) the developmental research cycle combined with Wenger’s (1998) communities of practice to analyse how the reflection group shifts the way of talking about communication and reasoning in mathematics teaching. In the analyses and the interpretation three concepts are used as analytical tools: mutual engagement, joint enterprise and shared repertoire. The results show shifts in the reflection group’s way of talking from to understand, to identify, to interpret and finally to apply mathematical reasoning in teaching. The result of the study also shows changes in the process as the conversation shifted from consensus to problematizing the common core question.

The number of students who use Swedish as a second language for their studies is increasing in Swedish Higher Education. This is a consequence of the fact that more upper secondary school students come from a foreign background and of the task of the universities to work for widening participation in Higher Education.

In spite of the increasing number of students using Swedish as a second language there is not much research on the use of L2 in Higher Education or the success of L2-students. One reason can be that the group is difficult to identify since language background is not a factor which is registered in the national statistics of students. L2-students are to be found within the wider group “students with a foreign background”. As a contribution to a better understanding of the use of language of L2-students in a Swedish context, I have looked at how students in their first year in a social science undergraduate programme meet an academic discourse and its demands on academic writing. The study is a text analysis which looks at the use of language in take-home examinations consisting of the instructions and questions of the teachers, the answers of the students and the results. The questions of the study are:

1. What language functions and what voice roles are embedded in questions in take-home examination for first year students on a social science undergraduate programme?

This question is answered by analysing the wording of the questions and the criteria for assessment in take-home examinations. The results of this analysis constitute the basis for my second research question:

1. How do first-year students with Swedish as their first or second language adapt their answers to the language functions and voice roles requested?

 I analyse the answers written by students who define Swedish as their first or second language, and I discuss the similarities and the differences in their strategies to meet the requirements. In order to study how L2-students meet the requirements of adaptation to the language of the discourse, my third research question is:

1. What voice roles do L2-students use in their examination answers?

I answer the question by a deeper analysis of some texts written by students with Swedish as their second language.

The theoretical framework is based on sociocultural theory, systemic functional linguistics, Academic Literacies and critical discourse analysis. The main conceptions of the study are language func­tions and voice roles. The language functions are the active verbs required in the instructions for the tasks and questions. The verbs are related to the cognitive levels of Bloom’s taxonomy.

The analysis of which voice roles are used and required in the instructions, and used in the answers, draws upon Hood’s (2004) description of voice roles. Following Hood I study the use of the following voice roles: the Observer voice, the Investigator voice and the Critic voice. The latter two are discursive roles and construct the Researcher role.

 In the analysis I study the language functions and voice roles in the texts of the students in the light of Ivanič’s (1998) expressions of identity: autobiographical self, discursive self and self as author.

 The group consisted of 31 students, 12 L1-students and 19 L2-students and 5 of the L2-students formed a group for close analysis of their answers to two essay questions. The material was collected in the academic year of 2010/2011 and consists of the instructions and questions of four take-home examinations and the answers of the students and their results. I have also analysed documents like the programme syllabus and course syllabi as background material. Two of the four take-home examination were chosen for close analysis. The answers of students to four of the questions in these two take-home examinations formed the basis for the analysis of the language use of the students.

The collected texts of the students consist of 96 answers in total, out of which 50 are included in the overall analysis and 10 of these are also included in the close analysis.

The studied take-home examinations consist of general instructions for how to answer the exam and also further instructions for each question. The questions are of three different types: short questions, longer questions and essay questions. In the instructions for the take-home examination, there are clear demands for an adaptation to an academic discourse. In these general descriptions, an expectation of all the three voice roles of Hood is included but it is the Researcher voices as Investigator voice and Critic voice, which are explicitly asked for.

The three voice roles are also asked for in the different phrasing of the questions but they are not explicitly asked for. Not all questions have to be answered in all the roles. It is the type of question that implies which voice role or voice roles the students are expected to use in their answers. The short questions can be answered in the voice role of the Observer and the longer questions implicate the voice roles of the Observer and the Investigator but to a certain extent also that of the Critic, whereas the essay questions require the students to use all the three voice roles in their answers. This means that the demand for the Researcher voice in the general instruction does not apply to all the different parts of the take-home exam, which can be confusing for first year students.

The language functions asked for in the exams represent all the six cognitive levels of Bloom’s revised taxonomy. However, each separate exam does not include all levels. Gradually there is a progression from the lower towards the higher levels. It is also possible to see a connection between the type of questions and language functions and thus a cognitive level. The short questions are used for the lower levels, essay questions are used for all levels. The language functions that occur most frequently and in different types of questions are to explain or describe something, and also to reason about something.

Based on the results of the analysis of the instructions and questions, a clear picture appears of what is asked for in the exam and what the students are expected to do to pass the exam.

On the basis of these results I analyse the students’ answers, especially the language func­tions: to explain, to define, to refer to, to reason about and to reflect on. An analysis of language functions is made on the answers to one short question, one longer question and one essay question in the first take-home exam and, finally, one essay question in the fourth take-home exam. The questions are chosen because the five language functions which I have identified as particularly relevant are asked for in them.

I can see that the answers of the two different groups of students show greater similarities than differences, overall. The answers are more colloquial and personal than academic. However, the texts demonstrate more interim language traits which illustrate that the students are aware of the academic language and strive to acquire the language of the discourse. The results are comparable with the results of studies of L2-students in the undergraduate English-speaking academic discourse (Hyland 2004, Ivanič 1998, Schleppegrell).

Not surprisingly, I found that the language functions that are higher in Bloom’s taxonomy are more difficult for the students. Level 4 – analysis – seems to be a critical level for many students but particularly for L2-students. The level of analysis is also the level that Rienecker & Stray Jørgensen regard as the lowest level for a good academic essay (2013: 48). Thus, the level is central to the academic language.

 In addition to the three voice roles defined by Hood, the Observer voice, the Investigator voice and the Critic voice, I was also able to identify the voice roles of the debater, the experiencer and the learner.

Crucial to the voice roles is whether they are taken by the student’s autobiographical self or discursive self. The experiencer and the learner are interim roles, which lie between the autobiographical and the discursive self and are not explicitly asked for in the instructions. For the student who is not familiar with the discourse, instructions to “reflect”, “reason about” and “give examples of your own” can imply that it is the voice roles as experiencer and learner which are required. The voice roles differ from the required ones by being taken from the students’ autobiographical self rather from their discursive self, as expected. When a voice role is taken by the students’ autobiographical self instead of the expected discursive self, new voice roles emerge and the text becomes less functional. The same effect arises when the wrong strategy, for example the choice of language function, is used to demonstrate a certain voice role.

A further observation is that the phrasing of the questions is crucial to which language functions and voice roles appear in the answers of the students. Some phrasings of questions lead the students in the wrong direction. For example, yes/no questions result in answers that resemble argumentative texts on lower levels in the educational system rather than the expository texts that are expected in the academic take-home examinations. The students have not understood the difference between arguing on an upper secondary school level and arguing in an academic context, nor have they understood the academic meaning of reasoning. The differences between L1- and L2-students’ adaptations to the demands of the discourse can be linked to which voice roles they take in the text and how they use their own voices in the texts. The results also show that even if both groups of students use a more colloquial language than expected, the L2-students, as a group, are closer to colloquial language and to the autobiographical self in their use of language than L1-students.

I have noticed that the use of language of the students in the form of voice roles and the adaptation to the required language functions are crucial to how well the texts function in their context. This probably influences how the texts are assessed and, thereby, how well the students succeed in their studies. A challenge for teachers is to give both new and experienced students adequate conditions and realistic opportunities to develop their use of language towards the academic target language. However, it is important that such teaching does not focus only on formal demands but goes below the surface of the text and creates an understanding of the reasons for the demands and expectations of the discourse in order to secure a common understanding of what is required in the examinations. The results in this study imply that teaching based on the levels of the taxonomies, expressed as language functions and the voice roles, can be a way to support the students in their acquisition of the academic discourse.

Translated by Anna Maria Staaf Wernheden

To enter higher education means making new experiences and develop newunderstanding within a knowledge field. The situation could also entail, for thestudent, an entirely different self-understanding. This licentiate thesis deals withthis kind of learning process.The overall aim of this licentiate thesis is to analyze what an art teachers education,founded on contemporary conceptual art, can offer in terms of transformativelearning. The point of departure is adults learning processes as renegotiations ofprevious interpretations which can be transformed to new understanding. The studyanalyzes what aspects of transformative learning are reflected in students' texts andimages, produced as part of the studied course. The licentiate thesis also discussespossibilities and constraints of this learning process. The study was conducted as acase study based on a hermeneutic approach. Material was collected from thecourse blog which consisted of students' texts and images.The study results show a transformative learning process which students experiencedas emotionally tumultuous because their self-image, as future art teachers, isrenegotiated. The situation contains a dimension of learning which I call "twistingand turning" in which new understanding is being formed. This situation requires aself-reflexive creative approach. The result generates questions about therelationship between the content of the education (what) and the learner (who) in anart teachers education founded on a non-traditional base. This applies above all ineducations that challenge students' prior understanding of a field. One could alsoask how adult learning is staged as relearning in higher education. The studydevelops a concept of reflexive creativity which contains a more abstract level thanjust problem solving. The idea of reflexive turn in art education, based onconceptually contemporary art, is also discussed.

This thesis consists of three parts. The first part is an introduction and referencessome recent work on 2D electromagnetic scattering problems at high frequencies. It alsopresents the basic integral equation types for impenetrable objects. A brief discussionof the standard elements of the method of moments is followed by summaries of thepapers.Paper I presents an accurate implementation of the method of moments for a perfectlyconducting cylinder. A scaling for the rapid variation of the solution improves accuracy.At high frequencies, the method of moments leads to a large dense system of equations.Sparsity in this system is obtained by modifying the integration path in the integralequation. The modified path reduces the accuracy in the deep shadow.In paper II, a hybrid method is used to handle the standing waves that are prominentin the shadow for the TE case. The shadow region is treated separately, in a hybridscheme based on a priori knowledge about the solution. An accurate method to combinesolutions in this hybrid scheme is presented.

In this work, I have mainly aimed to show how the results of previous field surveysin Misterhult parish, Småland province, Sweden have influenced past andcurrent research. Targeted surveys may in fact still change the picture radically.Our state of knowledge may also change through reviews of previous fieldworkand new excavations targeted at knowledge gaps. I have discussed Misterhult’sBronze Age and problems in that field. I have emphasised our current state ofknowledge and made a call for further fieldwork in the area. There is still muchto be done, and this study pinpoints what, in order to approach an answer towhat attracted people to the area 3000 years ago. Misterhult is one of NorthernEurope’s most extensive and best preserved Bronze Age settled landscapes, andconditions for research are good.In addition to surveys and the spatial site distribution, my focus has been on theunderlying economy, i.e. the economy behind the burial-cairn environments. Ihave tried to show that the economy was crucial to the design and ritualisationof those environments.

Most strength grading machines on the European market use an averagemodulus of elasticity (MOE), estimated on a relatively large distance along awood member, as the indicating property (IP) to bending strength. Theaccuracy of such grading machines in terms of coefficient of determination israther low at R² ≈ 0.5. This research is motivated by a desire to increase theaccuracy of the strength grading in the industry today. The aim of the presentstudy is to contribute knowledge of local variation in bending stiffness/MOEwith high resolution and thus locate weak sections due to stiffness reducingfeatures (the most important is knots) for structural timber.The present study introduces three methods that involve structural dynamics,classical beam theory and optical measurement to assess local wood stiffness.Specifically:

• The dynamic method, in which a wood member is treated as an ordinaryphysical structure and the local stiffness is studied by exploring itsdynamic properties.
• In Method II, a bending MOE profile is established based on local fibre angle information. The local fibre orientation is detected through highresolution laser scanning based on the tracheid effect.
•  For Method III, a bending MOE profile is established using surfacestrain information under four-point bending. A high resolution strainfield is obtained using the digital image correlation (DIC) technique.

From the present study, the two latter methods are more favourable inevaluating the local stiffness within a piece of structural timber. Moreover, thestudy reveals that the established bending MOE profiles using the two lattermethods, i.e. based on information of the local fibre angle and surface strain,agree reasonably well. However, for some patterns of knot clusters, the localbending MOE, calculated on the basis of fibre angles, is significantly higherthan the local bending MOE estimated on the basis of surface strain.

In industry, linear finite element models are commonly employed to represent global structural behavior. It is crucial that the computational models are able to accurately represent the structures’ behavior. This cannot always be achieved by the use of linear models.

When vibrational test data show significant nonlinear characteristics, an initial linear finite element model may be judged insufficient in representing the structural behavior. Although an initial model can give a good foundation for the understanding of the dynamic behavior of the structure, the parameters that capture the nonlinear effects are most likely not included. Therefore, a set of candidate parameters controlling the nonlinear effect have to be added. The selection of such candidates is a delicate task which solution is preferably supported by engineering insight into the characteristics of the structure.

One part of this work is on the selection of parameters, among all possibly uncertain properties, together with the forming of the objective function to be used for calibration. To obtain precise estimates of the parameters, the objective function data have to be informative with respect to the selected parameters. Further the parameters have to be identifiable. To improve these qualities, a multi-harmonic sinusoidal excitation was designed since the corresponding steady-state responses at the sub- and super- harmonics were shown to contain valuable information for the calibration process. Model calibration of nonlinear systems made by minimizing the differences between predicted and measured multi-harmonic frequency response functions.

Further, in the calibration, multi-harmonic frequency response functions need to be calculated recurrently in order to reach convergence; therefore a fast simulation scheme was required. The performance of computations of multi-harmonic frequency response functions calculated using time domain as well as frequency domain simulation techniques were studied and compared.

Finally, the proposed calibration method was validated by use of experimental testing on a replica of the Ecole de Lyon nonlinear benchmark structure. It was shown in the validation results that the predictions stemming from the calibrated model matched the experimental data well.

Målet med denna avhandling är att bidra med kunskap om hur digital teknik kan bidra till att utveckla matematikundervisning. I studien riktades intresset mot undervisning i tredimensionell geometri som skedde med stöd av interaktiva skrivtavlor. Syftet varatt studera hur läraren utnyttjar tekniken för att skapa matematiska situationer vilka kan möjliggöra lärande. Studien har en etnografisk inriktning där forskaren under fem veckor följdeen lärares teknikunderstödda undervisning i en klass i årskurs 9. Det empiriska materialet samlades in genom videounderstödd observation, intervju med läraren, fokusgruppsintervjuer med elever samt elevtester. Detta materialanalyserades med fokus på desätt på vilka läraren utnyttjar tekniken för att lyfta fram och arbetamed det matematiska innehållet. Resultatet visar att läraren utnyttjar flertalet strategier som tekniken erbjuder för att representera det matematiska innehållet och med teknikens hjälp växla mellan olika representationsformer, t.ex. genom att bearbeta, flytta och klona geometriska figurer. Läraren är överlag positiv till användande av teknik i matematikundervisningen, och de fördelar med tekniken som hon lyfter fram är att den hjälper och understödjerhenne utifrån de behov som uppstår i undervisningen och ger henne fler verktyg att belysa sådant som en del elever kan ha svårt att få syn på. Resultatet visar även att det fordras mycket arbete av läraren att sätta sig in i teknikens möjligheter och anpassa dessa till den egna undervisningen. Även eleverna är positiva till undervisning som sker med stöd av teknik då de menar att det hjälper dem att skapa sig en förståelse för tredimensionell geometri. Detta stärks av resultaten på det uppföljandetest som genomfördes efter arbetsområdet vilket visar att eleverna på ett påtagligt sätt utvecklat sin förståelse för geometriska begrepp.

The shift towards collegiality is a new setting for many teachers. Most teachers work alone, in isolation from their colleagues and collegial collaboration requires organisational structures. The aim of the study is to describe and analyse upper secondary mathematics teachers’ collective practice,developed in a professional development initiative. This study is a case study and the empirical data is generated through observations and an interview of a group of four teachers at a school who met on a weekly basis throughout a term. Their discussions focused on the mathematical concept of slope in a setting of learning study. This thesis is the case of when mathematics teachers focus discussions on slope and draws on Wenger’s Communities of Practice Perspective, as a unitof analysis, and addresses the question: What are the characteristics of practice when upper secondary mathematics teachers focus discussions on slope in the setting of a learning study? The analysis accounts for characteristics of the aspects of practice, through the coherence of mutual engagement, joint enterprise and shared repertoire in the community of practice. The teachers are engaged around finding small changes in their teaching that could give major effect in students learning. They negotiate what the students need to know in order to understand the relation between Δy and Δx. The characteristic of practice is a conceptual mapping of the concept of slope. It reveals students’ partial understanding of related concepts due to how they were given meaning through previous teaching. The conceptual mapping of slope goes back as far as to the student’s partial understanding of the meaning of subtraction. However, what emerges is in relation to the teachers’ experience of avoiding students’ difficulties with negative difference when teaching slope. It turns out to be a negotiation and a renegotiation of teaching slope for instrumental understanding or conceptual understanding. An overall characteristic of practice is that it develops in a present teaching culture.

Abstract

The permit application process for offshore wind farms (OWF) in Sweden conceivably requires a comprehensive and transparent complement within risk management. The NETEP framework (covering risks concerning navigation, economics, technology, environment and politics), based on a futures planning mechanism (STEEP) has consequently been brought forward as a structure for the application of FMECA (Failure Mode, Effects, and Criticality Analysis) methodology to the permit application process of the Swedish offshore wind farm sector. FMECA, originating from the aeronautical and automobile industries, presents a systematic method for the prediction of future failure in a product, part or process, to evaluate the consequences of that failure and to suggest possible measures for its mitigation or eradication. Its application to attitude and acceptance, safety and environmental effect remains, however, limited which creates the research gap for this thesis. Three Swedish offshore wind farm (OWF) projects in the Baltic Sea area (Lillgrund, Taggen and Trolleboda) were put forward as case studies for use in the evaluation of the proposed FMECA-NETEP methodology, which was approached in two stages. The first evaluation stage results showed that the model accommodates the precautionary principle, the consideration of stakeholder viewpoints, the mitigation of negative effects, the analysis of alternative sites, the observation of relevant legislation and the utilisation of contemporary research. In the subsequent stage of evaluation, the factor for incorporation into the adapted model was intra- and inter-sector cumulative impact. Results showed that positive cumulative impact cannot be illustrated by the model whereas neutral and negative cumulative impact can.  The model’s added value is that it facilitates decision making by providing a rigorous, transparent and structured methodology, the holistic approach of which provides a sound basis for the incorporation of contemporary research.

Essay 1: This paper studies tipping behaviour in the residential mobility of the native population inSweden between 1990 and 2007. Using regression discontinuity methods, we find that thegrowth in native population in a neighbourhood discontinuously drops once aneighbourhood’s immigrant share exceeds the identified tipping point. In the 1990s the dropcan be attributed both to increased out-migration of natives (native flight) and to thedecreased in-migration of natives (native avoidance) while native flight appears to be drivingthe segregation pattern between the years 2000 and 2007. Further, we find native migrationfrom neighbourhoods that have tipped is selective, in the sense that natives with a high levelof educational attainment are the most likely to move from such neighbourhood. We concludethat the native residential mobility has contributed to increased ethnic segregation but it alsoappears to have increased socio-economic segregation in Sweden between 1990 and 2007.

Essay 2: This paper focuses on second-generation immigrants and analyses the short- and long-termeffects of immigrant and ethnic group concentration in childhood neighbourhood on earnings,unemployment, reliance on income support and educational attainment. The results show thata high immigrant concentration in a childhood neighbourhood is negatively associated witheconomic outcomes of both second-generation immigrants and natives. Ethnic groupconcentration seems to work in the opposite direction, improving economic outcomes forsecond-generation immigrants. Furthermore, the results highlight the importance of includingtime dynamics in any analysis of the effect of childhood neighbourhood ethnic compositionon economic outcomes.

The study of functional data analysis is motivated by their applications in various fields of statistical estimation and statistical inverse problems.

In this thesis we propose a functional Hodrick-Prescott filter. This filter is applied to functional data which take values in an infinite dimensional separable Hilbert space.  The filter depends on a smoothing parameter. In this study we characterize the associated optimal smoothing parameter when the underlying distribution of the data is Gaussian. Furthermore we extend this characterization to the case when the underlying distribution of the data is white noise.

As of autumn 2011, all schools in Sweden have adopted and applied the latest curriculum for the compulsory school system. The following is written in concern to technology:

"The school is responsible for ensuring that each pupil on completing compulsory school: [...] can use modern technology as a tool in the search for knowledge, communication, creativity and learning." (Skolverket, 2011, pp.13-14)

With this said, there are no guidelines or manuals on how this is to be conducted. In a report from the Swedish Schools Inspectorate it was concluded that the investment in technology is not being used for school education. The education systems keep investing in technology in the belief that schools and teachers will sooner or later adopt and benefit from the use of mobile and ubiquitous technologies.

The aim of this study is to “create an understanding of the aspects that have an impact on adopting novel use of mobile and ubiquitous technologies in everyday teaching and learning practices in compulsory schools.”

The empirical foundation will be based upon three projects: Geometry Mobile (GeM); Learning Ecology with Technologies from Science for Global Outcomes (LETS GO); and Collaborative Learning Using Digital Pens and Interactive Whiteboards (Collboard). All were conducted at local compulsory schools in Växjö municipality, Sweden, in collaboration with teachers, students and fellow researchers from the CeLeKT research group at Linnaeus University.

Two Thematic Analyses have been conducted: the first, an inductive analysis exploring the Students’ and Teachers’ Experience of using Mobile and Ubiquitous Technologies in their learning and teaching environment. The second analysis is deductive and uses themes from the Unified Theory of Acceptance and Use of Technology models with the aim of understanding the Perception and Acceptance of Teachers’ use of Mobile and Ubiquitous Technologies. In the results from the two analyses there are clear indicators on the added value that mobile and ubiquitous technology brings to the classrooms: students are able to actively participate, collaborate and discuss in different learning settings, which enhances their understanding of the subject at hand. The challenges are mainly to be found in the lack of training and education in use of the technology as a supporting tool for teaching and learning. Further factors influencing the teachers and the students are ease of use and reliability of the technology and societal changes.

The results of the analysis and the theoretical base of Technology Enhanced Learning have been illustrated with Soft Systems Methodologies Rich Picture, providing a holistic view of the problematic situation and making it possible to discuss the various parts as well as the situation as a whole. This study indicates that there are several factors influencing the adoption of the novel use of mobile and ubiquitous technologies in everyday teaching and learning within a complex situation on different levels. 

This thesis is about the shape stability of laminated veneer products.

Laminated veneer products consist of veneers bonded together with adhesive into a predetermined shape. Such products are used in several contexts but especially in furniture manufacture. Deviation from the intended shape is a problem for both manufacturers and customers of the final products. The shape stability of laminated veneer products depends on a variety of material and process parameters, and this thesis identifies several important factors that influence shape stability. The purpose of this thesis is to find ways to decrease distortion and improve shape stability so that product quality can be improved.

Different ways of measuring shape stability, both in an industrial environment and in a more research-based context, are presented in this thesis. Various studies have been conducted to evaluate the influence of different material and process parameters on shape stability. The parameters studied were species (beech and birch), adhesive system (bio-based adhesives, adhesive systems based on urea formaldehyde), adhesive distribution on the veneer, climate, moisture content and fibre orientations of the veneers, as well as orientation of the individual veneers in an assembly.

The results clearly show that the fibre orientation of the veneer strongly influences the shape stability of a laminated veneer product. This means that products can show considerable distortion (particularly twist) if the fibre orientation of the veneer is orientated in an unsuitable way in the assembly before moulding. The effect of fibre orientation on shape stability can be very small directly after moulding, but it increases considerably when the moulded product is subjected to a change in moisture content. In general, a change in moisture content leads to distortion. Moisture change alone, however, results in a controlled distortion.

An asymmetrical construction coupled with different moisture contents of the veneers in an assembly before moulding will result in poor shape stability of the product. Other studied parameters had a low impact on shape stability, although beech resulted in more distortion and poorer shape stability than birch.

In order to produce shape-stable laminated veneer products, the veneers should be conditioned to a uniform moisture content and sorted with regard to fibre orientation before bonding. The orientation of the veneers is highly important regarding both fibre orientation and the loose or tight side of the veneer. If shape stability is the main target, the loose sides of peeled and sliced veneers should be oriented in the same manner.

Gäng i dess olika former, vare sig det är lokala ambulerande gatugäng eller sofistikerade, internationella kriminella gäng, är ett allt större problem i vårt samhälle. Gäng skapar enorma kriminella vinster från grov brottslig verksamhet och undergräver allvarligt allmänhetens förtroende för samhällets institutioner såsom polisen och socialtjänsten. Att förebygga gäng och gängkriminalitet, är därför ett prioriterat område såväl på nationell som på internationell nivå. Tusen fiender - behandlar de svenska gatugängen och dess ledare, med syftet att öka vår kunskap och förståelse om vilka sociala processer och faktorer som bidrar till att gäng bildas i Sverige. Studierna som Tusen fiender bygger på ,utgår ifrån 239 gängmedlemmar, tagna ur sju självmarkerande svenska gatugäng med tydlig gäng- och lagbrytande identitet, samt intervjuer med 24 gängmedlemmar varav tolv gängledare.

The integration of mobile and sensor technologies, and the design and implementation of different web-enabled visualizations to support inquiry learning in different educational scenarios encompass the main research efforts carried out in this thesis. These challenges are addressed from the perspectives of mobile and web engineering, visualization and technology-enhanced learning (TEL). Thus, the main research question investigated in this thesis relates to the identification of the main features that can guide the design and implementation of web and mobile applications to support inquiry learning in different contexts.

This thesis consists of a collection of four publications that describe the research efforts conducted during a period of three years in relation to the Learning Ecology through Science with Global Outcomes (LETS GO) research project. The research questions investigated and the implemented technological solutions reported in these publications are closely related to the main goals and challenges of this thesis. The design and implementation of the proposed software system was guided, deployed and refined having the following aspects in mind: (1) System Requirements and Architectural Design, (2) System Implementation and Deployment, and (3) System Assessment and Web Usability Testing. During the three years of development efforts, three software prototypes were implemented utilizing service-oriented approaches. These efforts have been tested with more than 200 users in connection to several trials that took place during this period. The user trials allowed testing the software application throughout three development iterations on authentic settings, while new requirements continuously emerged in these activities. This process made it possible to verify that user requirements were adequately addressed while satisfying their needs.

The outcomes of these activities led to the design and implementation of a system architecture that relies on service-oriented approaches and open standards. The main outcomes of this thesis are presented in the form of Architectural Concepts, as they can be used to guide the design and implementation of web and mobile applications to support inquiry learning. The idea behind architectural concepts is to provide a set of tools for supporting the overall life cycle of a software development process, such as requirements, design, implementation, deployment and testing while coping with rapid changes of technological implementations. Some of the architectural concepts identified in this thesis correspond well with the kind of support that inquiry-learning activities require. They provide solid foundations in terms of possibilities to tackle the requirements for supporting inquiry learning in a flexible manner.

Derivation of an electromagnetic model, regarding the wave propagation in a very long (10 km or more) High Voltage Direct Current (HVDC) power cable, is the central part of this thesis. With an existing “perfect” electromagnetic model there are potentially a wide range of applications.The electromagnetic model is focused on frequencies between 0 and 100 kHz since higher frequencies essentially will be attenuated. An exact dispersion relation is formulated and the propagation constant is computed numerically. The dominating mode is the first Transversal Magnetic (TM) mode of order zero, denoted TM01, which is also referred to as the quasi-TEM mode. A comparison is made with the second propagating TM mode of order zero denoted TM02. The electromagnetic model is verified against real time data from Time Domain Reflection (TDR) measurements on a HVDC power cable. A mismatch calibration procedure is performed due to matching difficulties between the TDR measurement equipment and the power cable regarding the single-mode transmission line model.An example of power cable length measurements is addressed, which reveals that with a “perfect” model the length of an 80 km long power cable could be estimated to an accuracy of a few centimeters. With the present model the accuracy can be estimated to approximately 100 m.In order to understand the low-frequency wave propagation characteristics, an exact asymptotic analysis is performed. It is shown that the behavior of the propagation constant is governed by a square root of the complex frequency in the lowfrequency domain. This thesis also focuses on an analysis regarding the sensitivity of the propagation constant with respect to some of the electric parameters in the model. Variables of interest when performing the parameter sensitivity study are the real relative permittivityand the conductivity.

Essay 1: Swedish micro and macro data on internal migration indicate that home-owners on average have a higher propensity to migrate to other labour market areas in response to higher unemployment and job vacancy rates than renters and tenant-owners. This is evidence that owning your home does not constrain labour mobility across labour market areas in comparison to other forms of housing tenure. The response to high local job vacancy rates indicates that migration in general is driven by differences in matching efficiency in local labour market areas rather than a pure response to high local unemployment. A third finding is that at higher levels of aggregation high unemployment is associated to high levels of home-ownership as previous researchers have found. The suggested explanation for this correlation, i.e. that home-ownership constrains mobility of individuals, however, seems falsified in Sweden by our results.

Essay 2: Swedish micro and macro data on internal migration indicate that interregional migration responds to regional labour market conditions and individual unemployment. Migration is found to go from relatively high unemployment and high job vacancy to low unemployment and low job vacancy regions contrary to earlier research. The response to job vacancy rates indicate that migration responds to differences in local Beveridge curves and migration goes towards better matching efficiency. Unemployment on the individual level is found to increases the propensity for interregional migration.

Dahl, Thomas (2012). Problemlösning kan avslöja matematiska förmågor. Att upptäcka matematiska förmågor i en matematisk aktivitet (Problem-solving can reveal mathematical abilities: How to detect students‟ abilities in mathematical activities). Linnéuniversitetet 2012; ISBN:978-91-86983-28-4. Written in Swedish.The thesis deals with the problem of identifying and classifying components of mathematical ability in students‟ problem-solving activities. The main theoretical framework is Krutetskii‟s theory of mathematical abilities in schoolchildren. After a short historical background focusing on the question of differentiation or integration among students on the basis of their various aptitudes for studies, the theory of mathematical ability and especially the Krutetskiian theory are described. According to Krutetskii mathematical ability should be looked upon as a structure of seven or eight different components called abilities which may appear and be subject to analysis during a mathematical activity.Krutetskii used school pupils and experimental problems to establish the relevance of his structure of abilities. However, in this work the theme is approached from the opposite perspective: If a problem and an experimental person are given, which mathematical abilities will appear and in what ways do they appear in the mathematical activity? The empirical study uses three so called “rich mathematics problems” and 98 students of which 37 study at the lower secondary school, 39 at the upper secondary school and 22 at the teacher education programme. The output data is either the written outcomes of the students‟ individual work on a problem or the recordings from small groups of students solving a problem in cooperation with their peers.In order to identify and classify abilities, the separate components of mathematical ability must be interpreted and adapted to the specific problem on which the students are working. I call this process of conformation of the abilities operationalization and the question in focus is if such an operationalization can be done successfully. The results indicate that it could be done and several examples are given which show how one or several mathematical abilities may come out more or less strongly in the mathematical activity of problem solving. The results also indicate that even low or average achieving students may show significant creative abilities. Another observation from the empirical study is that creative abilities do not seem to be more abundant among upper than lower secondary students. These two observations point out possible pathways to proceed further in the study of mathematical abilities.

The main purpose of this thesis is to explore the safety culture onboard vessels trading in the Baltic Sea. The common denominator for vessels trading in the Baltic Sea is frequent port visits, coastal voyages, voyages in dense trafficked areas and small crews. Earlier research shows that there may be a system fault in the shipping industry. Charles Perrow describes the maritime industry as an error inducing system. He means that the cause for that is the way shipping is carried out. In a safety culture values, attitudes, competence and behavioral patterns are four important factors that define the safety culture. The maritime safety management system, International Safety Management Code (ISM) aims towards a proactive and evolutionally safety culture in the shipping industry. The results show that shipping today lacks a foresight, “failure of foresight”, where the proactive way of work leads to incidents and accidents being anticipated.

This study has an ethnographic perspective, which aims to create a thick and substantial description of the culture that is being studied. Totally a number of eleven vessels participated in the study. The visits onboard reach from a couple of hours up to a few days. Collected data has been analysed through a self-developed model in an ambition to try to explain the safety culture. The model focuses on how information, feedback, responsibility, co-operation, follow-up and development are being handled. The study reveals that there is a need to discuss and change the safety culture in the shipping industry, in large as on the single vessel. As well as a need for further studies of how the safety culture can be improved and a need for education aimed towards system thinking, organizational theory and safety culture.

Thermal stresses can arise in glass used in architectonic realisations in buildings as a result of solar irradiation:  that is, sunlight.  The magnitude of these thermal stresses depends on the temperature conditions in the glass in terms of the temperature differences between warm and cold areas. 

The work described here has verified the existence and distribution of thermal stresses in glass, both theoretically and experimentally, in a load-bearing element made of glass and wood, when exposed to incident solar radiation and various degrees of shading. 

The finite element method was used in order to simulate the temperature distribution in the glass, together with the resulting associated thermal stresses.  Parts of these model results were then compared with results and data from experimental investigations in a solar simulator.  The experimental trials were carried out on a plain glass sheet and on a wood-framed glass sheet.  This frame assembly saw the glass fitted in a wooden frame such that its edge was flush with the edges of the frame and therefore freely exposed to the surroundings.  Two different grades of glass were analysed in the theoretical modelling and used in the experimental solar exposure:  a clear glass, with a low absorption coefficient, and a tinted glass having a relatively high absorption coefficient.  The experimental part of the work included two different finishes to the glass edge:  as-cut, with no further attention, and cut and smoothed. 

The results from the finite element method calculations agree relatively well with the experimental results.  When simulating the temperature values and distributions, the value of the coefficient of heat transfer is an important factor in determining the results.  The coefficient can be given either a constant value, taken from a standard, or a calculated value that varies depending on the surface temperature and ambient temperature at every instant.  For the clear glass with a low coefficient of absorption, the calculated temperatures did not differ significantly depending on which method had been used to provide a value for the coefficient of heat transfer.  However, for the glass with a high coefficient of absorption, and when exposed to high solar intensity, a calculated value of coefficient of heat transfer should be used in order to arrive at relevant values of surface temperatures and stresses.  Thermal tensile stresses have more effect on the total stress level than have stresses arising from typical in-service vertical loads.

 Many open challenges exist when dealing with different biological networks. They are crucial for the understanding of living beings. Complete drawings of these typically large networks usually suffer from clutter and visual overload. In order to overcome this issue, the networks are divided into single, hierarchically structured pathways. However, this subdivision makes it harder to navigate and understand the connections between pathways. Another challenge is to visualize ontologies and hierarchical clusterings, which are important tools to study high-throughput data that are automatically generated nowadays. Both of these methods produce different types of large graphs. Although these methods are used to explore the same data set, they are usually considered independently. Therefore, a combined view showing the results of both methods is desired. Additionally, real life data sets, including biological networks, usually have additional attributes related to the considered network. Investigating means to visualize such multivariate data together with the network drawing is also one of the ongoing challenges in biology, but also in other fields.

The aim of this thesis is to lay out the foundations towards defining techniques for the visualization of multivariate biochemical networks. An overall understanding of the problems related to biochemical networks should be acquired to achieve this aim. More importantly, a contribution to the aforementioned challenges is necessary.

Two research goals have been defined to accomplish our aim: for the first goal, we should improve shortcomings of the approach of dividing larger biological networks into smaller pieces and contribute to the problem of a visualization of different types of interconnected biological networks. The second goal is a contribution for the visualization of multivariate biological networks.

Initially, a brief survey on techniques to visualize multivariate networks is presented in this thesis. Then, various visualization and interaction techniques are presented that address the challenges in biochemical network analysis. Three different software tools were implemented to demonstrate our research efforts. We discuss all features of our systems in detail, describe the visualization and interaction techniques as well as disadvantages and scalability issues if present.

The presence of computer technologies in our daily life is growing by leaps and bounds. One of the recent trends is the use of mobile technologies and cloud services for supporting everyday tasks and the sharing of information between users. The field of education is not absent from these developments and many organizations are adopting Information and Communication Technologies (ICT) in various ways for supporting teaching and learning. The field of Mobile Learning (M-Learning) offers new opportunities for carrying out collaborative educational activities in a variety of settings and situations. The use of mobile technologies for enhancing collaboration provides new opportunities but at the same time new challenges emerge.

One of those challenges is discussed in this thesis and it con- cerns with uncertainties related to the dynamic aspects that characterized outdoor M-Learning activities. The existence of these uncertainties force software developers to make assumptions in their developments. However, these uncertainties are the cause of risks that may affect the required outcomes for M-Learning activities. Mitigations mechanisms can be developed and included to reduce the risks’ impact during the different phases of development. However, uncertainties which are present at runtime require adaptation mechanisms to mitigate the resulting risks.

This thesis analyzes the current state of the art in self-adaptation in Technology-Enhanced Learning (TEL) and M-Learning. The results of an extensive literature survey in the field and the outcomes of the Geometry Mobile (GEM) research project are reported. A list of uncertainties in collaborative M-Learning activities and the associated risks that threaten the critical QoS outcomes for collaboration are identified and discussed. A detailed elaboration addressing mitigation mechanisms to cope with these problems is elaborated and presented. The results of these efforts provide valuable insights and the basis towards the design of a multi-agent self-adaptive architecture for multiple concerns that is illustrated with a prototype implementation. The proposed conceptual architecture is an initial cornerstone towards the creation of a decentralized distributed self-adaptive system for multiple concerns to guarantee collaboration in M-Learning. 

The general intention of recent Swedish legislation concerning adults with intellectual disabilities has been to provide care and support for this group in small settings in the community. It has been shown that adults with intellectual disabilities are better equipped to exert influence over their own care and support when living in group homes in the community and other forms of independent living as opposed to large institutional settings. Recent research on this group has to a great extent concerned the study of how life is in small group homes for this group and has highlighted obstacles preventing them from participating in society. Previous research has indicated that living in institutional settings makes it difficult for them to exert influence on their lives. A small number of large institutional care settings still exist, however, in Sweden and there is a dearth of research that focuses on how adults with intellectual disabilities experience everyday life in such settings. In addition, little research has been carried out on the role of the care workers who work in such settings. The aim of this research has thus been to describe the experiences of adults with intellectual disabilities and care workers of living and working in an institutional care setting in Sweden.

An ethnographic approach including participant observation and in-depth interviews was used to gain a deeper understanding of how adults with intellectual disabilities and staff experience their everyday life in an institutional care setting. The result showed that the residents experienced;  I) a sense of belonging, which was connected to having access to a private sphere and being part of social togetherness;  II) a feeling of insecurity in relation to other residents and care workers;  III) a longing for independence and a desire to get away. The study of the staff revealed three main themes that represent their approach; I) creating a family-like atmosphere; II) making the everyday life ordered and structured; III) being exposed to stress factors.

The results revealed the importance of paying close attention to what adults with intellectual disabilities and their care workers have to say about their everyday lives when living and working in an institutional care setting. It may be concluded that adults living in an institutional care setting experience their everyday lives in existential terms such as belonging, insecurity and longing. For caring science and in caring practices of people with intellectual disabilities, it is not satisfactory that residents experience such an insecure existence in a care setting. In order to provide individual care and support, staff need to be more open and vigilant as to the residents’ vulnerability and be able to guide them in matters  concerning emotional aspects. It was seen that care workers in their everyday work with residents in an institutional care setting used experiences from their personal lives in situations where they lacked formal care training. Such experiences may have helped to create meaningfulness but at the same time risked preserving inequality and gender stereotyping. In order to avoid these risks care workers should receive clear directives from the management about the care objectives, and guidelines about how best to care for adults with intellectual disabilities and offer them individualized care. Furthermore, it also became evident that care workers need additional support, training and opportunities for reflection to cope with their complex work situation. The results of this research can contribute to a greater insight and deeper knowledge of what adults with intellectual disabilities experience in an institutional care setting in the 2000’s , enabling the staff and management to further enhance the well-being for this group of individuals. The findings can provide feedback to staff, managers and researchers working in the intellectual disabilities field.

Keywords: adults with intellectual disabilities, care, care workers, ethnography, institutional care setting, Sweden

Information is one of the most essential resources in our contemporary societies, as it guideshuman thinking, planning and subsequent actions, which in turn generates consequencesthat are desired or not. The Lehman Brothers bankruptcy in 2008, the tsunami in Indonesiain 2004, the Space Shuttle Challenger destruction in 1986 are just three instances ofdramatic situations, emerging continuously, where information plays a crucial role. Thisstudy investigates the phenomenon of the lack of needed information, predominantlyexperienced with difficulties in human, social and industrial affairs. Consequently, thechallenge is to understand why such situations emerge. Two approaches are utilized toexplore this challenge using an interpretivist tradition. The first is a hermeneutic approach,the second a grounded theory approach. The first approach – theoretically oriented –investigates numerous theoretical bodies, selected with the assumption that they can explainthe addressed challenge. The results show that there are no comprehensive theoreticalbodies that can fully account for the phenomenon of the lack of needed information.Furthermore, there is no consensus on what “information” is – the very core of thechallenge, which gave the foundations for a formulation of an alternative notion ofinformation and is instrumental for the present investigation. Thus, no a priori theory isused to guide the empirical investigation. The second approach – empirically oriented –investigates fifty empirical cases, where the lack of needed information is clearly manifested.The results present an initial outline for a possible future theory of information inadequacy,constituted by the dichotomy of information-lack and information-overflow. Informationlackis dominated by: “information is non-existent”, “information is insufficient”, “information is censored” and “information is undelivered”. Whereas, information-overflow isdominated by: “information is ambiguous”, “information is redundant”, “information isirrelevant” and “information is undervalued”. The two main dichotomous characteristics andtheir interrelations result in patterns of various information inadequacies. The keyconclusion of the present study is that while dramatic situations are increasing everyday,there is as yet no theoretical body designed to comprehensively account for the phenomenonin context; only partial accounts are found. Thus, the empirical investigation suggests thatthe phenomenon of the lack of needed information seems to emerge because of diversefactors, ranging from political and cultural structures, through human individualcapabilities, and ending with procedural and technological artefacts. This study advocatesthat further research is needed to fully account for and explain instances of the lack ofneeded information, and that such an account requires an innovative and interdisciplinary focus.

Processing decision information is a constitutive part in a number of applicationsin Computer Science fields. In general, decision information can be used to deduce the relationship between a certain context and a certain decision. Decision information is represented by a decision model that captures this information. Frequently used examples of decision models are decision tables and decision trees. The choice of an appropriate decision model has an impact on application performance in terms of memory consumption and execution time. High memory expenses can possibly occur due to redundancy in a decision model; and high execution time is often a consequence of an unsuitable decision model.

Applications in different domains try to overcome these problems by introducing new data structures or algorithms for implementing decision models. These solutions are usually domain-specificand hard to transfer from one domain to another. Different application domains of Computer Science often process decision information in a similar way and, hence, have similar problems. We should thus be able to present a unifying approach that can be applicable in all application domains for capturing and manipulating decision information. Therefore, the goal of this thesis is (i) to suggest a general structure(Decision Algebra) which provides a common theoretical framework that captures decision information and defines operations (signatures) for storing, accessing, merging, approximating, and manipulating such information along with some general algebraic laws regardless of the used implementation. Our Decision Algebra allows defining different construction strategiesfor decision models and data structures that capture decision information as implementation variants, and it simplifies experimental comparisons between them.

Additionally, this thesis presents (ii) an implementation of Decision Algebra capturing the information in a non-redundant way and performing the operations efficiently. In fact, we show that existing decision models that originated in the field of Data Mining and Machine Learning and variants thereof as exploited in special algorithms can be understood as alternative implementation variants of the Decision Algebra by varying the implementations of the Decision Algebra operations. Hence, this work (iii) will contribute to a classification of existing technology for processing decision information in different application domains of Computer Science.

Traditional approaches to knowledge collaboration and sharing have proven to be limited in the sense of addressing organizational needs of dynamic and distributed knowledge. More recently, the emergence of social media and the second generation of web technologies have introduced new ways and possibilities for sharing knowledge in organizations. In particular, the wiki technology, as one type of social media, is argued to mark a shift in the way people collaborate and share knowledge with each other on the web. It represents a new, open style of knowledge collaboration and sharing which allows anyone to freely and openly create and shape knowledge. In this respect, organizations have been attracted by this new dynamic approach which is based on open collaboration and flexible participation. More organizations are using wikis in order to effectively leverage distributed knowledge and improve their competitive edge. Against this backdrop, this research is concerned with examining how such organizations use social media, the wiki technology in particular, for sharing knowledge among individuals and groups. The aim is twofold: to develop an understanding of the ways by which these individuals and groups exchange and share knowledge with each other and to identify different factors that influence knowledge collaboration and sharing using a wiki in an organizational setting. The research is based on three published research papers which provide both theoretical and empirical accounts of knowledge collaboration and sharing using wikis. To these ends of this research, an interpretive case study was used as an empirical research method with interviews as primary sources of data. Several other data sources have been triangulated during the empirical inquiry including field visits, observations, and documents. The case took place at a large multinational organization that used a wiki as a collaborative platform to support knowledge sharing among members of several professional communities of practice. Eventually, the outcome of the research is a thorough understanding that describes knowledge collaboration and sharing using a wiki as a dynamic social process involving recursive and dynamic social interactions among members of communities of practice through which knowledge is collaboratively constructed and reconstructed and thus shared. It also presents a dual impact of wiki openness on knowledge collaboration and sharing within organizations.

The study of p-adic dynamical systems is motivated by their applications in various (and surprisingly diverse) areas of mathematics, e.g., in physics, genetics, biology, cognitive science, neurophysiology, computer science, cryptology, etc.

In this thesis we use decomposition of a continuous function f : zp -> zp into a convergent van der Put series to determine whether f is 1-Lipschitz, measure-preserving and/or ergodic.

The main mathematical tool used in this research is the representation of the function by the van der Put series, which are special convergent series from p-adic analysis.

This is the first attempt to use the van der Put basis to examine the properties of (discrete) dynamical systems in fields of p-adic numbers. Note that the van der Put basis differs fundamentally from previously used ones, for example, the monomial and Mahler bases, which are related to the algebraic structure of p-adic fields.

The van der Put basis is related to the zero dimensional topology of these fields (ultrametric structure), since it consists of characteristic functions of p-adic balls; i.e., the basic point in the construction of this basis is the continuity of the characteristic function of a p-adic ball.

This thesis investigates the needs and opportunities for the Swedish wood house industry to obtain wood material with properties meeting demands of both producers and final customers. A common problem within the Swedish wood house industries is the insufficient quality of the wood material that companies purchase for their production. These flaws in quality can render an additional annual cost for the industry of approximately 10 million Euros.

Wood house companies express a certain resignation regarding communication with wood material suppliers. However, timber suppliers claim that they rather receive very few complaints regarding timber quality from wood house companies and other purchasers. For a timber supplier, being able to offer an acceptable price is often a determining factor, since most deals will go to the supplier offering the lowest price.

This has led to a non-existent dialogue between suppliers and purchasers regarding how to approach the wood quality issue. This study has, among other things, studied the preparation of sawn wood into finished components, for instance, the production of knotfree boards. The results illustrate the importance of carrying out evaluations of raw material and suppliers. Furthermore, results show that the cutting cost for wood components, including waste is approximately 1/3 of the total cost for ready-made components. However, in relation to the total cost of the house the timber cost is low. This means that a higher price for wood that fully meets the target specifications, will have limited impact on the total cost for the house.

The wood house industry is recommended to present firm demands for a high-quality material and to evaluate material and suppliers. In addition to this, the wood house industry should aim towards becoming a modern manufacturing industry, like those most successful manufacturing industries in other fields.

Wind power is one of the fastest growing energy sources, which have advantages in terms of delivering clean, cheap and fast energy. Many actors and organizations have realized this potential, which has lead to exponential growth of the wind power over recent couple of years. Despite promising future of clean and green energy through wind there are still areas to be improved to tackle main hinders for further development on a larger scale. The larger scale development of wind power has up-to-date been reached in only few countries such asDenmarkandGermany. The most potential can be found through offshore wind turbines due to, among other, lesser height and noise restrictions than inland wind turbines as well as better wind resources.

This thesis is mainly characterized by the mixed-method method, which is in its turn characterized by mixing different research methods such as induction, deduction and abduction as they might be suitable to apply during the different stages of the research process. In this thesis the system approach will be considered to model the scope of this study’s context. As this thesis was constructed as a theoretical study the systematic literature review was used as the main source for data collection. The synthesis of the reviewed articles was initially performed in a broad manner to show overall picture of research related to the scope of this thesis. In the following step, the adopted LCM tool was used to extract study specific data from the reviewed and additional articles. This enabled to link some of the current problems, in wind power area, and ‘unfulfilled’ stakeholder requirements.   

This thesis aim was to identify important stakeholders and to address their respective requirements within the scope of supportability engineering applied in the wind power context, particularly stakeholder requirements that have not been considered by previous research. The purpose of it was to compare different requirements with current issues in the wind power sector. Conducted systematic literature review showed significant and costly (development) issues related to the supportability engineering such as reliability, availability, maintainability, accessibility problems etc. This was fully in line with the stakeholders’ requirements, which in several cases demanded higher dependability i.e. availability performance and its influencing factors. 

The thesis also included definition of supportability engineering framework, through comparing several widely accepted and standardized theoretical concepts. This comparison enabled definition of more focused approach with requirements on the ‘supported system’ and to lesser extent the ‘support system’. These requirements are usually mixed within the different theoretical concepts. 

The main findings from this study are that application of supportability engineering framework would lead to earlier identification of important stakeholders and their requirements. Considering these requirements, for instance availability and maintainability of the wind turbines, at earlier stages of the life cycle through better design and improved supportability infrastructure could potentially decrease amount of current problems in the wind energy sector in particular for the offshore part. Another result was that different stakeholders and their requirements were identified. Thesis contribution overall was a new ‘refined approach’ to deal with supportability issues through supportability engineering framework, whose main focus is the ‘supported system’.