Branch and Bound Algorithm for Multiprocessor Scheduling

The multiprocessor task graph scheduling problem has been extensively studied asacademic optimization problem which occurs in optimizing the execution time of parallelalgorithm with parallel computer. The problem is already being known as one of the NPhardproblems. There are many good approaches made with many optimizing algorithmto find out the optimum solution for this problem with less computational time. One ofthem is branch and bound algorithm.In this paper, we propose a branch and bound algorithm for the multiprocessor schedulingproblem. We investigate the algorithm by comparing two different lower bounds withtheir computational costs and the size of the pruned tree.Several experiments are made with small set of problems and results are compared indifferent sections.

Upper secondary school students' gendered conceptions about mathematics

This study explores Swedish Natural Science students' conceptions about gender and mathematics. I conducted and compared the results from two questionnaires. The first questionnaire revealed a view of rather traditional feminities and masulinities, a result that did not repeat itself in the second questionnaire. There was a discrepancy between the traits the students ascribed as gender different and the traits they ascribed to themselves.

On statistical bounds of heuristic solutions to location problems

Solutions to combinatorial optimization problems, such as problems of locating facilities, frequently rely on heuristics to minimize the objective function. The optimum is sought iteratively and a criterion is needed to decide when the procedure (almost) attains it. Pre-setting the number of iterations dominates in OR applications, which implies that the quality of the solution cannot be ascertained. A small, almost dormant, branch of the literature suggests using statistical principles to estimate the minimum and its bounds as a tool to decide upon stopping and evaluating the quality of the solution. In this paper we examine the functioning of statistical bounds obtained from four different estimators by using simulated annealing on p-median test problems taken from Beasley’s OR-library. We find the Weibull estimator and the 2nd order Jackknife estimator preferable and the requirement of sample size to be about 10 being much less than the current recommendation. However, reliable statistical bounds are found to depend critically on a sample of heuristic solutions of high quality and we give a simple statistic useful for checking the quality. We end the paper with an illustration on using statistical bounds in a problem of locating some 70 distribution centers of the Swedish Post in one Swedish region. 

A web-based system for visualizing upper limb motor performance of Parkinson’s disease patients

Objective To design, develop and set up a web-based system for enabling graphical visualization of upper limb motor performance (ULMP) of Parkinson’s disease (PD) patients to clinicians. Background Sixty-five patients diagnosed with advanced PD have used a test battery, implemented in a touch-screen handheld computer, in their home environment settings over the course of a 3-year clinical study. The test items consisted of objective measures of ULMP through a set of upper limb motor tests (finger to tapping and spiral drawings). For the tapping tests, patients were asked to perform alternate tapping of two buttons as fast and accurate as possible, first using the right hand and then the left hand. The test duration was 20 seconds. For the spiral drawing test, patients traced a pre-drawn Archimedes spiral using the dominant hand, and the test was repeated 3 times per test occasion. In total, the study database consisted of symptom assessments during 10079 test occasions. Methods Visualization of ULMP The web-based system is used by two neurologists for assessing the performance of PD patients during motor tests collected over the course of the said study. The system employs animations, scatter plots and time series graphs to visualize the ULMP of patients to the neurologists. The performance during spiral tests is depicted by animating the three spiral drawings, allowing the neurologists to observe real-time accelerations or hesitations and sharp changes during the actual drawing process. The tapping performance is visualized by displaying different types of graphs. Information presented included distribution of taps over the two buttons, horizontal tap distance vs. time, vertical tap distance vs. time, and tapping reaction time over the test length. Assessments Different scales are utilized by the neurologists to assess the observed impairments. For the spiral drawing performance, the neurologists rated firstly the ‘impairment’ using a 0 (no impairment) – 10 (extremely severe) scale, secondly three kinematic properties: ‘drawing speed’, ‘irregularity’ and ‘hesitation’ using a 0 (normal) – 4 (extremely severe) scale, and thirdly the probable ‘cause’ for the said impairment using 3 choices including Tremor, Bradykinesia/Rigidity and Dyskinesia. For the tapping performance, a 0 (normal) – 4 (extremely severe) scale is used for first rating four tapping properties: ‘tapping speed’, ‘accuracy’, ‘fatigue’, ‘arrhythmia’, and then the ‘global tapping severity’ (GTS). To achieve a common basis for assessment, initially one neurologist (DN) performed preliminary ratings by browsing through the database to collect and rate at least 20 samples of each GTS level and at least 33 samples of each ‘cause’ category. These preliminary ratings were then observed by the two neurologists (DN and PG) to be used as templates for rating of tests afterwards. In another track, the system randomly selected one test occasion per patient and visualized its items, that is tapping and spiral drawings, to the two neurologists. Statistical methods Inter-rater agreements were assessed using weighted Kappa coefficient. The internal consistency of properties of tapping and spiral drawing tests were assessed using Cronbach’s α test. One-way ANOVA test followed by Tukey multiple comparisons test was used to test if mean scores of properties of tapping and spiral drawing tests were different among GTS and ‘cause’ categories, respectively. Results When rating tapping graphs, inter-rater agreements (Kappa) were as follows: GTS (0.61), ‘tapping speed’ (0.89), ‘accuracy’ (0.66), ‘fatigue’ (0.57) and ‘arrhythmia’ (0.33). The poor inter-rater agreement when assessing “arrhythmia” may be as a result of observation of different things in the graphs, among the two raters. When rating animated spirals, both raters had very good agreement when assessing severity of spiral drawings, that is, ‘impairment’ (0.85) and irregularity (0.72). However, there were poor agreements between the two raters when assessing ‘cause’ (0.38) and time-information properties like ‘drawing speed’ (0.25) and ‘hesitation’ (0.21). Tapping properties, that is ‘tapping speed’, ‘accuracy’, ‘fatigue’ and ‘arrhythmia’ had satisfactory internal consistency with a Cronbach’s α coefficient of 0.77. In general, the trends of mean scores of tapping properties worsened with increasing levels of GTS. The mean scores of the four properties were significantly different to each other, only at different levels. In contrast from tapping properties, kinematic properties of spirals, that is ‘drawing speed’, ‘irregularity’ and ‘hesitation’ had a questionable consistency among them with a coefficient of 0.66. Bradykinetic spirals were associated with more impaired speed (mean = 83.7 % worse, P < 0.001) and hesitation (mean = 77.8% worse, P < 0.001), compared to dyskinetic spirals. Both these ‘cause’ categories had similar mean scores of ‘impairment’ and ‘irregularity’. Conclusions In contrast from current approaches used in clinical setting for the assessment of PD symptoms, this system enables clinicians to animate easily and realistically the ULMP of patients who at the same time are at their homes. Dynamic access of visualized motor tests may also be useful when observing and evaluating therapy-related complications such as under- and over-medications. In future, we foresee to utilize these manual ratings for developing and validating computer methods for automating the process of assessing ULMP of PD patients.

Online and Offline Gaming as Support for English Education in Swedish Upper Elementary Schools with Focus on Reading Comprehension Online and Offline Gaming as Support for English Education in Swedish Upper Elementary Schools with Focus on Reading Comprehension : A literature review about online and offline gaming as a resource for developing English reading comprehension in Swedish schools in year 4-6

The aim of this degree thesis is to see what research says about the use of computer and video games to support upper elementary pupils’ development in English reading comprehension in Swedish schools. Other goals are to see how online and offline gaming can be integrated in the Swedish schools and what attitudes teachers have towards gaming. The method used is a systematic literature review and the purpose is to analyze chosen articles and to find relevant content that answers the research questions. Five articles were chosen from different databases and were systematically analyzed in this thesis. The results show that online gaming as support for education can be rewarding for some upper elementary pupils in English learning. However, in English reading comprehension there is not much research found which means that more research needs to be made within this area. Moreover, involving online gaming in English language learning seems to be a challenge for teachers mostly because of their lack of knowledge about the subject, even though they are positive to gaming. The lack of knowledge about the subject could be altered with more education and courses in the area.

Teaching grammar: A study of the common English grammar errors and grammar teaching methods that can be relevant for Swedish upper secondary schools

Grammar has always been an important part of language learning. Based on various theories, such as the universal grammar theory (Chomsky, 1959) and, the input theory (Krashen, 1970), the explicit and implicit teaching methods have been developed. Research shows that both methods may have some benefits and disadvantages. The attitude towards English grammar teaching methods in schools has also changed and nowadays grammar teaching methods and learning strategies, as a part of language mastery, are one of the discussion topics among linguists. This study focuses on teacher and learner experiences and beliefs about teaching English grammar and difficulties learners may face. The aim of the study is to conduct a literature review and to find out what scientific knowledge exists concerning the previously named topics. Along with this, the relevant steering documents are investigated focusing on grammar teaching at Swedish upper secondary schools. The universal grammar theory of Chomsky as well as Krashen’s input hypotheses provide the theoretical background for the current study. The study has been conducted applying qualitative and quantitative methods. The systematic search in four databases LIBRIS, ERIK, LLBA and Google Scholar were used for collecting relevant publications. The result shows that scientists’ publications name different grammar areas that are perceived as problematic for learners all over the world. The most common explanation of these difficulties is the influence of learner L1. Research presents teachers’ and learners’ beliefs to the benefits of grammar teaching methods. An effective combination of teaching methods needs to be done to fit learners’ expectations and individual needs. Together, they will contribute to the achieving of higher language proficiency levels and, therefore, they can be successfully applied at Swedish upper secondary schools.

English-medium instruction in Sweden : Perspectives and practices in two upper secondary schools

This thesis presents English-medium instruction (EMI) in the Swedish context, focusing on perspectives and practices in two schools. The research question is as follows: How and why is EMI offered, chosen, and practiced in the Swedish upper secondary school today? The aim is to explore the status of the educational option, the reasons for offering EMI to stakeholders, the stakeholders’ beliefs about and goals of EMI, and the implementation of EMI in the classroom. A survey of all upper secondary schools in Sweden was conducted to ascertain the spread of content teaching through a foreign language. The educational context was studied from an ecological perspective using methods based in linguistic ethnography. Language alternation, academic language, and language hierarchy were all considered. Interviews were analysed for content; and classroom language use was analysed for language choice and function. The concepts of affordance and scaffolding together with translanguaging were key. The de facto policies of the micro contexts of the schools were examined in light of the declared national policy of the macro context of Sweden. The results indicate that the option in Swedish schools has not increased, and also tends to only be EMI—not Content and Language Integrated Learning (CLIL) or instruction through other languages. EMI is offered for prestige, an international profile, marketing potential and personal interest. EMI students are academically motivated and confident, and see the option as “fun”. 100% EMI in the lessons is not the goal or the practice. Translanguaging is abundant, but how language alternation is perceived as an affordance or not differs in the two schools. One focuses on how the languages are used while the other focuses on how much each language is used. In conclusion, the analysis suggests that a development of definitions and practices of EMI in Sweden is needed, especially in relation to language policy and language hierarchy.

Learning by Reading : A literature study on the use of authentic texts in the EFL upper elementary classroom

The English language is widely used throughout the world and has become a core subject in many countries, especially for students in the upper elementary classroom. While textbooks have been the preferred EFL teaching method for a long time, this belief has seemingly changed within the last few years. Therefore, this study looks at what prior research says about the use of authentic texts in the EFL upper elementary classroom with an aim to answer research questions on how teachers can work with authentic texts, what the potential benefits of using authentic texts are and what teachers and students say about the use of authentic texts in the EFL classroom. While this thesis is written from a Swedish perspective, it is recognized that many countries teach EFL. Therefore, international results have also been taken into consideration and seven previous research studies have been analyzed in order to gain a better understanding of the use of authentic texts in the EFL classroom. Results indicate that the use of authentic texts is beneficial in teaching EFL. However, many teachers are still reluctant to use these, mainly because of time constraints and the belief that such texts are too difficult for their students. Since these findings are mainly focused on areas outside of Sweden, additional research is needed before conclusions can be drawn on the use of authentic texts in the Swedish upper elementary EFL classroom.

English as the target language : A literature study on teachers’ and L2 learners’ language use in the upper elementary classroom

Even though English is a subject where Swedish pupils do well compared to pupils in other countries, research indicates that pupils are not always motivated to learn in the English classroom. Therefore, the aim of this study is to find research relating to the use of the target language in classrooms for pupils at the upper elementary level, particularly language learners in Sweden. The focus of this thesis is to find out what benefits and challenges accompany the use of the target language during English lessons, as well as what pupils’ opinions are on the consistent use of the target language in the classroom. This literature review of five research articles shows that it is beneficial for pupils’ language development to have lessons where mainly the target language is used. It is for example beneficial for pupils’ ability to speak, their pronunciation, vocabulary and ability to use language strategies. The results show that there are challenges as well, especially for the teachers, since use of the target language presumes that the teacher has good language skills and is capable of scaffolding each pupil at their individual level and in their zone of proximal development. Furthermore, there are challenges like differences in pupils’ skill level, creating tasks that both motivate and stimulate, and creating a safe learning environment. Even though the results in this thesis are limited, it is still obvious that it is an important area, where more research is necessary in order to assist teachers in how to teach English as effectively as possible.

An Empirical Study on Teachers’ Choice of Extensive Literature in the Swedish Upper Secondary EFL Classroom

The importance of extensive literature reading in the English as a Foreign Language (EFL) context has been given increasing attention in recent research. Literature reading is also a required part of the national syllabi of the (EFL) courses offered to both adolescents and adults at Upper Secondary level in Sweden. This thesis aims to investigate the teachers’ process of making literature choices for extensive reading in upper secondary EFL courses in Sweden. Eight teachers of three different student groups took part in the study, representing adolescent university preparatory programs and vocational programs, as well as programs for adult students. Questionnaires were used and the data was analyzed for patterns revealing three main factors affecting teachers’ literature choice: language proficiency, reading experience and contextual factors. These three factors were fitted into the theoretical framework of psycholinguistic and sociolinguistic reading models, with the addition of a perspective of motivational research. The results of this survey underline the importance of extensive reading, according to teachers, and that motivation for literature choice can be primarily related to factors associated with psycholinguistic reading models. The survey also points to the need for further investigating of teachers’ own experiences of literature reading, searching for deeper motivational factors which influence teaching choices. Another future field of research is the choice of reading activities assigned together with the chosen literature, which probably also influence teachers’ choices in the Swedish EFL classroom.

L1 Use in the EFL-classroom : A Literature Review on Teachers’ Use of the L1 in the EFL-classroom on Upper Secondary Level

Even though English should mainly be used in the EFL-classroom according to the Swedish national curriculum, some recent scholars have argued that a judicious use of the students’ L1 by the teachers in some particular situations may benefit the learning environment there. From this context, this thesis examines what research says about in what particular situations the L1 is used by teachers in upper secondary EFL-classrooms as well as the teachers’ and the students’ attitudes towards this practice. The method used was a systematic literature review, where seven articles from all across the globe were analyzed, compared and synthesized. The results show that the L1 was mainly used by the teachers when managing discipline, when explaining grammar and when teaching vocabulary. However, the articles did not conclude how the L1 could be used strategically by the teachers. Concerning the teachers’ and students’ attitudes, the majority of these were positive towards L1 use by the teacher in the above mentioned situations. However, the teachers were not aware of how the L1 could be used by them in a judicious and a strategic way. Lastly, it can be concluded that more research is needed on how the L1 can be used more strategically by the teachers as well as on the students’ perspective on this.

The Role of Motivational Strategies in the Upper Elementary Classroom : A systematic literature review about teacher strategies that promote self-confidence, motivation and a conducive learning environment

The aim of this literature review is to investigate which strategies teachers use to motivate pupils to communicate orally in English. The literature review also investigates how these teacher strategies affect pupils. The methodology used for this investigation is a systematic literature review. Various databases have been used when searching for literature. Scientific articles and theses have been searched for. They have also been read and analyzed before they have become a part of this review. The results indicate that some teachers feel insecure when speaking English. Therefore Swedish is spoken in many language classrooms. Teachers speaking in front of the class is the traditional way of teaching, and it does not seem to be a strategy who influences pupils positively. If teachers speak the target language among pupils they often get more motivated and focused pupils who feel comfortable speaking English. Young pupils are fast learners. By exposing them to the English language in early ages they receive great opportunities to learn a foreign language and strengthen their self-confidence. Drama, songs and rhymes are preferable strategies to use when teaching young learners. What position teachers decide to take in the classroom is also a significant element when teaching foreign languages.

How initial vocational education and training (IVET) teachers in Sweden perceive their prospects of being able to prepare upper secondary school pupils for a future occupation

Vocational teachers in Swedish upper secondary schools are a heterogeneous category of teachers, connected to different types of trade. These teachers represent a broad set of trade skills varying in content and character. In their teacher role, they continue to wear the clothes, speak the language, share the culture and remain mentally in their former professions. Still, it is central that they keep up this contact to be able to school the pupils into the environment of the trade in question, but also to help them to understand what skills a profession demands. However, the individual teacher also has to distance himself from the negative elements in the culture of the profession: patterns and habits that, for various reasons, have to be broken or changed. This paper draws attention to the ways in which a group of vocational teachers, who were participants in a project that aimed to train unauthorized vocational teachers, expressed their ambitions to prepare the pupils for a future professional career. When collecting information, we used the degree dissertations they produced and discussed in seminars, and informal dialogues. The result shows that it is important that the instruction location resembles a real working site as far as possible. These places are more or less realistic copies of a garage, a restaurant kitchen, a hairdressing salon, and so on, in order to give the pupils a realistic setting for instruction. However, the fact that these simulated workplaces lack the necessary support functions that exist in a company creates problems, problems which make a lot of extra work for the teachers. Vocational teachers also have to instruct the pupil in the experienced practitioner’s professional skills and working situation, but the pupil herself/himself must learn the job by doing it in practice. Some vocational upper secondary programs lack relevant course literature and the businesses give little support. This also makes extra work for the teachers. Moreover, the distance between the vocational programs and the trainee jobs was experienced as being difficult to overcome. One reason seems to be differences between businesses and differing preconditions between small and big companies’ abilities to take care of these pupils. The upper secondary school vocational programs also play a role in cementing existing gender roles, as well as perpetuating class-related patterns on the labour market.

Must teachers be social workers, as well …? : Reflections on the current teacher role in the Swedish upper secondary school and how it affects teacher training

The Swedish upper secondary school has made a transition from a school for the elite to be a school for everybody. When almost every youth nowadays chooses to continue studying, for some of them this is not what they want to do most of all. However, as there in practice is no choice, there come up problems and many upper secondary school teachers experience a growing frustration. We will here discuss some aspects of the following questions: -  How do upper secondary schoolteachers handle their working-conditions in a new situation? - What possible consequences do this have on teacher education?