Tuberculosis (TB) is a two-stage disease, acquisition of infection and progression to disease. A complex interaction exists between the individual and their environment that determines who acquires infection and who progresses to disease. According to TB literature, 10% of individuals with infection will develop TB disease (1;2). Tuberculosis has been described a disease of poverty, but other factors may be important. The contribution of both individual measures, such as ethnic origin, gender and age and area-level measures, or socio-economic factors, to this two-stage process is not well understood. Understanding tuberculosis epidemiology and identifying those at risk for developing TB is important for effectively controlling the disease. The objective of this study was to determine the individual (age, gender, ethnic origin, geographic location) and area-level measures (income, home ownership, housing density, education, and employment) that contribute to the progression from tuberculosis infection to disease. Data from all Canadian-born Caucasians, Status Indians, and non-Status Indians and Metis, with an initial positive tuberculin skin test (TST) documented in the Saskatchewan TB Control database from January 1, 1986 to January 31, 2002 was analyzed. Exclusion criteria included any previous BCG vaccination, treatment for latent TB infection, or missing data. Individual data was obtained from the TB Control database. Area-level measures were obtained by matching individual postal codes with Canada census data to obtain information from enumeration areas. Outcome was time to TB disease at > 1 month following a documented positive tuberculin skin test. Analysis was completed using Cox regression proportional hazards model. 7588 individuals with a positive tuberculin skin test were included in the study and of these 338 (4.5%) developed TB disease. Thirty-four out of 4140 (0.8%) of Caucasians, 183 out of 2649 (6.9%) of Status Indians and 121 out of 799 (15.1%) non-Status Indians and Metis developed TB. The rate of progression to TB was 5.6/1000 person years for the entire study population. The incidence for Caucasians was 0.9/1000 person years, 7.7/1000 person years for Status Indians and 16.0/1000 person years for non-Status Indians and Metis. In the Cox regression model, including individual and area-level measures, the risk factors association with the progression to TB was age and ethnic origin (< 19 years of age HR 3.7, 95% CI 2.8 - 4.8 compared to > 19 years and ethnic origin HR 5.1, 95% CI 3.0 - 8.6 for Status Indians and HR 7.4, 95% CI 4.1-13.3 for non-Status Indians and Metis both compared to Caucasians). No socio-economic factor was consistently associated with progression to disease. We have found that age and ethnic origin are associated with an increased risk of TB infection progressing to disease. The differences in TB rates between Saskatchewan Caucasians and Status Indians, non-Status Indians and Metis can be explained by Grigg's natural history curve of TB epidemiology within a population (3). The Aboriginal population of Saskatchewan is much earlier in its epidemic resulting in higher disease rates compared to the Caucasian population. Identifying those at risk of developing TB and understanding the determinants of TB epidemiology are important for establishing successful TB control programs.

The aim of this study was to examine the view that officials involved in youth unemployment have on the significance of collaboration between organizations working with unemployed youth. The study was based on nine qualitative interviews with officials from PES offices and from municipalities such as job coaches. The results were analyzed based on qualitative content analysis. The analysis led to two different themes: conditions and the individual. In the analysis two different theories were used, new institutionalism and Lipsky's theory about street-level bureaucrats. The analysis led us to the conclusion that these officials find collaboration important both for their work and for the unemployed youth and that they collaborate with the individual’s interests in mind.

Tuberculosis (TB) is a two-stage disease, acquisition of infection and progression to disease. A complex interaction exists between the individual and their environment that determines who acquires infection and who progresses to disease. According to TB literature, 10% of individuals with infection will develop TB disease (1;2). Tuberculosis has been described a disease of poverty, but other factors may be important. The contribution of both individual measures, such as ethnic origin, gender and age and area-level measures, or socio-economic factors, to this two-stage process is not well understood. Understanding tuberculosis epidemiology and identifying those at risk for developing TB is important for effectively controlling the disease. The objective of this study was to determine the individual (age, gender, ethnic origin, geographic location) and area-level measures (income, home ownership, housing density, education, and employment) that contribute to the progression from tuberculosis infection to disease. Data from all Canadian-born Caucasians, Status Indians, and non-Status Indians and Metis, with an initial positive tuberculin skin test (TST) documented in the Saskatchewan TB Control database from January 1, 1986 to January 31, 2002 was analyzed. Exclusion criteria included any previous BCG vaccination, treatment for latent TB infection, or missing data. Individual data was obtained from the TB Control database. Area-level measures were obtained by matching individual postal codes with Canada census data to obtain information from enumeration areas. Outcome was time to TB disease at > 1 month following a documented positive tuberculin skin test. Analysis was completed using Cox regression proportional hazards model. 7588 individuals with a positive tuberculin skin test were included in the study and of these 338 (4.5%) developed TB disease. Thirty-four out of 4140 (0.8%) of Caucasians, 183 out of 2649 (6.9%) of Status Indians and 121 out of 799 (15.1%) non-Status Indians and Metis developed TB. The rate of progression to TB was 5.6/1000 person years for the entire study population. The incidence for Caucasians was 0.9/1000 person years, 7.7/1000 person years for Status Indians and 16.0/1000 person years for non-Status Indians and Metis. In the Cox regression model, including individual and area-level measures, the risk factors association with the progression to TB was age and ethnic origin (< 19 years of age HR 3.7, 95% CI 2.8 - 4.8 compared to > 19 years and ethnic origin HR 5.1, 95% CI 3.0 - 8.6 for Status Indians and HR 7.4, 95% CI 4.1-13.3 for non-Status Indians and Metis both compared to Caucasians). No socio-economic factor was consistently associated with progression to disease. We have found that age and ethnic origin are associated with an increased risk of TB infection progressing to disease. The differences in TB rates between Saskatchewan Caucasians and Status Indians, non-Status Indians and Metis can be explained by Grigg's natural history curve of TB epidemiology within a population (3). The Aboriginal population of Saskatchewan is much earlier in its epidemic resulting in higher disease rates compared to the Caucasian population. Identifying those at risk of developing TB and understanding the determinants of TB epidemiology are important for establishing successful TB control programs.

The aim of this thesis is to find out if there is a gap between the formalization level and the realization level in the Namibian school system. Moreover, our aim is to figure out how we, as visiting teaching students, interpret the relationship between steering documents and the teaching in the classroom. In turn, the aim was used to formulate three different research questions: What can we experience while observing in the class room/at school? What do the interviewed teachers express concerning our asked questions? What are the main differences between the two latest steering documents? The reason why we decided to do a study about the school system in Namibia is because it is a young country, it was proclaimed independent in 1990. Therefore we think it is interesting to study how the school system and its political steering documents have developed over the years. Our theoretical framework includes the concept of curriculum, reconceptualism and cultural issues. Our focal point has been on the following three perspectives, democracy, gender and learner centred education. The method we used in this study is triangulation, in this case analyzing political steering documents, interviewing teachers and other people connected to the school and finally class room observations. The attitudes to the three above mentioned perspectives vary amongst the interviewed personnel This study as come to the conclusion that there is a gap between the formalization level and realization level.

Sound wave has much better transmission in ocean environment than electromagnetic waves, therefore sonar systems are widely applied in underwater investigations. However, not only the target signal is received by the sonar but also the noise from different directions. The noise will affect the performance of the sonar, so the understanding of ocean ambient is an important issue both in academic study and military applications. The ambient noise data of this research was collected by a passive acoustic recording system deployed in the southwest sea of Taiwan, along with the information of wind velocity in the experimented area. The influence on noise level fluctuations by the variation of the wind velocity was first discussed in light of correlation analysis. The fluctuations were expressed in terms of statistic distribution, mean value, standard deviation in different time series. As results, 500 Hz and 1.5k Hz were saturated by high levels signal from unknown sources in spring and summer, so the average sound levels were higher than in fall and winter, about 10 dB and 5 dB higher for 500 Hz and 1.5k Hz respectively. In seasonal analysis, 2.4k and 3.6k Hz have quite stable the mean levels and their standard deviations were around 3 dB. Especially, the noise level of 3.6 Hz has the least fluctuation throughout the year than any other frequencies analyzed. It was also observed that the noise level was decreased with the increase of frequency. Calculated by linear regression, this research worked out the estimation equation for the ambient noise level at high wind speed. However, the estimated values are higher than the measured data, it is due to the distribution of wind velocity. The wind data in this study was skewed towards the lower velocity, consequently the predicted values were overestimated.

In recent years, many researches focused on the supervised machine learning classification methods using Lidar and remotely sensed image to provide buildings, trees, roads, and grass categories for urban ground feature classification. First, this research performed urban ground feature classification based on true color aerial imagey and Lidar Intensity. Second, Lidar derived normalized DSM (nDSM) was added to the classification. Finally, the concept of height level rules was applied. This research utilized two-level height rule-based classification exteneded from three-level height rule-based classification (Huang, 2007). It is obvious to observ the overlap for the roads and houses, and grass and trees in the feature space plot where result in the classification confusion. These confusions can be resolved by fusion the height information. After comparing classification accuracy, the two-level height is better than three-level height classification scheme. This research proposed hybrid classification method based on Maximum likelihood classification (MLC) and two-level height rules. This method reveals the role of height information in urban ground feature classification. The height level rules were also applied to other supervised classification method such as Back-Propagation Network (BPN) and Support Vector Machine (SVM). The classification results show that the accuracy of hybrid method is better than the orgional classification method. However, the time required to look for the classification parameters for BPN and SVM is greater than MLC but only can derived considerable results. Therefore, the hybrid classification method based on MLC is better than other two methods.

In the Internet of Services (IoS) providers and consumers of services engage in business interactions on service marketplaces. Provisioning and consumption of services are regulated by service level agreements (SLA), which are negotiated between providers and consumers. Trading composite services requires the providers to manage the SLAs that are negotiated with the providers of atomic services and the consumers of the composition. The management of SLAs involves the negotiation and renegotiation of SLAs as well as their monitoring during service provisioning. The complexity of this task arises due to the fact that dependencies exist between the different services in a composition. Dependencies between services occur because the complex task of a composition is distributed between atomic services. Thus, the successful provisioning of the composite service depends on its atomic building blocks. At the same time, atomic services depend on other atomic services, e.g. because of data or resource requirements, or time relationships. These dependencies need to be considered for the management of composite service SLAs. This thesis aims at developing a management approach for dependencies between services in service compositions to support SLA management. Information about service dependencies is not explicitly available. Instead it is implicitly contained in the workflow description of a composite service, the negotiated SLAs of the composite service, and as application domain knowledge of experts, which makes the handling of this information more complex. Thus, the dependency management approach needs to capture this dependency information in an explicit way. The dependency information is then used to support SLA management in three ways. First of all dependency information is used during SLA negotiation the to ensure that the different SLAs enable the successful collaboration of the services to achieve the composite service goal. Secondly, during SLA renegotiation dependency information is used to determine which effects the renegotiation has on other SLAs. Finally, dependency information is used during SLA monitoring to determine the effects of detected violations on other services. Based on a literature study and two use cases from the logistics and healthcare domains different types of dependencies were analyzed and classified. The results from this analysis were used as a basis for the development of an approach to analyze and represent dependency information according to the different dependency properties. Furthermore, a lifecycle and architecture for managing dependency information was developed. In an iterative approach the different artifacts were implemented, tested based on two use cases, and refined according to the test results Finally, the prototype was evaluated with regard to detailed test cases and performance measurements were executed. The resulting dependency management approach has four main contributions. Firstly, it represents a holistic approach for managing service dependencies with regard to composite SLA management. It extends existing work by supporting the handling of dependencies between atomic services as well as atomic and composite services at design time and during service provisioning. Secondly, a semi-automatic approach to capturing dependency information is provided. It helps to achieve a higher degree of automation as compared to other approaches. Thirdly, a metamodel for representing dependency information for SLA management is shown. Dependency information is kept separately from SLA information to achieve a better separation of concerns. This facilitates the utilization of the dependency management functionality with different SLA management approaches. Fourthly, a dependency management architecture is presented. The design of the architecture ensures that the components can be integrated with different SLA management approaches. The test case based evaluation of the dependency management approach showed its feasibility and correct functioning in two different application domains. Furthermore, the performance evaluation showed that the automated dependency management tasks are executed within the range of milliseconds for both use cases. The dependency management approach is suited to support the different SLA management tasks. It supports the work of composite service providers by facilitating the SLA management of complex service compositions.

Silicon carbide (SiC) is currently under development for high power bipolar devices such as insulated gate bipolar transistors (IGBTs). A major issue for these devices is the charge carrier lifetime, which, in the absence of structural defects such as dislocations, is influenced by point defects and their associated deep levels. These defects provide energy levels within the bandgap and may act as either recombination or trapping centers, depending on whether they interact with both conduction and valence band or only one of the two bands. Of all deep levels know in 4H-SiC, the intrinsic carbon vacancy related Z1/2 is the most problematic since it is a very effective recombination center which is unavoidably formed during growth. Its concentration in the epilayer can be decreased for the production of high voltage devices by injecting interstitial carbon, for example by oxidation, which, however, results in the formation of other new deep levels. Apart from intrinsic crystal flaws, extrinsic defects such as transition metals may also produce deep levels within the bandgap, which in literature have so far only been shown to produce trapping effects. The focus of the thesis is the transient electrical and optical characterization of deep levels in SiC and their influence on the carrier lifetime. For this purpose, deep level transient spectroscopy (DLTS) and minority carrier transient spectroscopy (MCTS) variations were used in combination with time-resolved photoluminescence (TRPL). Paper 1 deals with a lifetime limiting deep level related to Fe-incorporation in n-type 4H-SiC during growth and papers 2 and 3 focus on identifying the main intrinsic recombination center in p-type 4H-SiC. In paper 4, the details of the charge carrier capture behavior of the deeper donor levels of the carbon vacancy, EH6/7, are investigated. Paper 5 deals with trapping effects created by unwanted incorporation of high amounts of boron during growth of n-type 4H-SiC which hinders the measurement of the carrier lifetime by room temperature TRPL. Finally, paper 6 is concerned with the characterization of oxidation-induced deep levels created in n- and p-type 4H- and 6H-SiC as a side-product of lifetime improvement by oxidation. In paper 1, the appearance of a new recombination center in n-type 4H-SiC, the RB1 level is discussed and the material is analyzed using room temperature TRPL, DLTS and pnjunction DLTS. The level appears to originate from a reactor contamination with Fe, a transition metal that generally leads to the formation of several trapping centers in the bandgap. Here it is found that under specific circumstances beneficial to the growth of high-quality material with a low Z1/2 concentration, the Fe incorporation also creates an additional recombination center capable of limiting the carrier lifetime. In paper 2, all deep levels found in p-type 4H-SiC grown at Linköping University which are accessible by DLTS and MCTS are investigated with regard to their efficiency as recombination centers. We find that none of the detectable levels is able to reduce carrier lifetime in p-type significantly, which points to the lifetime killer being located in the top half of the bandgap and having a large hole to electron capture cross section ratio (such as Z1/2, which is found in n-type material), making it undetectable by DLTS and MCTS. Paper 3 compares carrier lifetimes measured by temperature-dependent TRPL measurements in n- and p-type 4H-SiC and it is shown that the lifetime development over a large temperature range (77 - 1000 K) is similar in both types. This is interpreted as a further indication that the carbon vacancy related Z1/2 level is the main lifetime killer in p-type. In paper 4, the hole and electron capture cross sections of the near midgap deep levels EH6/7 are characterized. Both levels are capable of rapid electron capture but have only small hole capture rates, making them insignificant as recombination centers, despite their advantageous position near midgap. Minority carrier trapping by boron, which is both a p-type dopant and an unavoidable contaminant in 4H-SiC grown by CVD, is investigated in paper 5. Since even the shallow boron acceptor levels are relatively deep in the bandgap, minority trap and-release effects are detectable in room-temperature TRPL measurements. In case a high density of boron exists in n-type 4H-SiC, for example leached out from damaged graphite reactor parts during growth, we demonstrate that these trapping effects may be misinterpreted in room temperature TRPL measurements as a long free carrier lifetime. Paper 6 uses MCTS, DLTS, and room temperature TRPL to characterize the oxidation induced deep levels ON1 and ON2 in n- and p-type 4H- and their counterparts OS1-OS3 in 6H-SiC. The levels are found to all be positive-U, coupled two-levels defects which trap electrons efficiently but exhibit very inefficient hole capture once the defect is fully occupied by electrons. It is shown that these levels are incapable of significantly influencing carrier lifetime in epilayers which underwent high temperature lifetime enhancement oxidations. Due to their high density after oxidation and their high thermal stability they may, however, act to compensate n-type doping in low-doped material.

This study focuses on investigating if specific aspects in texture design, used in the 3D-Models implemented in 3D-digital games, can influence a player's action. The method used is a minor section of a game called a level being constructed for player testing. The level has 6 rooms each with 2 out of 6 different designs of doors. The player will choose one, and with an interview tell us why he or she picked that door. I found that the players choose logic, rather than discomfort, when choosing a door as the choice often was about where the door lead. As the test shows interesting results, it validated my hypthesis in terms of whether a design can affect the player’s choices. / Den här studien fokuserar på att undersöka specifika sidor I textur design som kan påverka en spelares val. Metoden som användes är ett mindre område i spel kallad Level som designades för spelare att testa. Level består av 6 rum med 2 av 6 olika designs på dörrar i varje rum, spelaren väljer en dörr och med en intervju förklarar varför han eller hon valde just den dörren. Jag fann att spelare hellre gjorde logiska val än ett val ledd av obehag när de valde dörr då valet ofta var om vart dörren leder till. Testet visar intressanta resultat men bekräftar också min hypotes när det gäller om en dörr design kan påverka en spelares val.

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