This thesis deals with the design and realization of wireless electronic timer for fire sport. The first part of thesis provides an analysis of the given problems and all component parts of the system which are needed for time measurement in the fire sport. The principal aim of thesis was to create a wireless electronic timer for simultaneous measurement of up to four lanes. The designed measuring system is equipped with a large LED display to show the final time. Targets and starting pistols are wirelessly connected with the main unit of timer with using a communication platform IQRF. The whole device is structural designed to the handling was as simple as possible.

abstract: Stress-related failure such as cracking are an important photovoltaic (PV) reliability issue since it accounts for a high percentage of power losses in the midlife-failure and wear-out failure regimes. Cell cracking can only be correlated with module degradation when cracks are of detectable size and detrimental to the performance. Several techniques have been explored to access the deflection and stress status on solar cell, but they have disadvantages such as high surface sensitivity. This dissertation presents a new and non-destructive method for mapping the deflection on encapsulated solar cells using X-ray topography (XRT). This method is based on Bragg diffraction imaging, where only the areas that meet diffraction conditions will present contrast. By taking XRT images of the solar cell at various sample positions and applying an in-house developed algorithm framework, the cell‘s deflection map is obtained. Error analysis has demonstrated that the errors from the experiment and the data processing are below 4.4 and 3.3%. Von Karman plate theory has been applied to access the stress state of the solar cells. Under the assumptions that the samples experience pure bending and plain stress conditions, the principal stresses are obtained from the cell deflection data. Results from a statistical analysis using a Weibull distribution suggest that 0.1% of the data points can contribute to critical failure. Both the soldering and lamination processes put large amounts of stress on solar cells. Even though glass/glass packaging symmetry is preferred over glass/backsheet, the solar cells inside the glass/glass packaging experience significantly more stress. Through a series of in-situ four-point bending test, the assumptions behind Von Karman theory are validated for cases where the neutral plane is displaced by the tensile and compressive stresses. The deflection and stress mapping method is applied to two next generation PV concepts named Flex-circuit and PVMirror. The Flex-circuit module concept replaces traditional metal ribbons with Al foils for electrical contact and PVMirror concept utilizes a curved PV module design with a dichroic film for thermal storage and electrical output. The XRT framework proposed in this dissertation successfully characterized the impact of various novel interconnection and packaging solutions. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2019

Zusammenfassung "Prozessgebundene Berechnungs-Baugruppen bieten Konstrukteuren die Möglichkeit, ihre zum Teil mehrstufigen Berechnungen durch den Einsatz modularer Funktionsbausteine ablauforientiert, verbindlich, nachvollziehbar und vor allem zeitsparender zu gestalten. Die Grundlage dieser neuen Methode bilden Ansätze, die sich bereits in der Informationstechnik und in der Konstruktionsmethodik bewährt haben. Vom Anforderungsmanagement bis zur Validierung kann dabei auf eine Bibliothek modularer Berechnungsobjekte in Form von Prozess-Bausteinen zugegriffen werden, deren Schnittstellen und Datenstrukturen ausnahmslos einheitlichen Definitionen entsprechen. Gemeinsam mit der in Anlehnung an den eCl@ss - Standard entwickelten Merkmalsstruktur der Prozess-Bausteine wird so eine hohe Wiederverwendbarkeit in unterschiedlichen Berechnungskonfigurationen erzielt. Ihre Klassifizierung orientiert sich an konstruktionssystematischen Gesichtspunkten. Die Methode wird beispielhaft an Berechnungen für Getriebekomponenten erläutert."

The goal of this thesis is to, on behalf of JB Eco Tech, investigate a novel method of interconnecting photovoltaic (PV) modules. The principle is to stick the interconnecting strings on the cells with a transparent tape instead of soldering. As a part of the assembly process, the module is laminated under heat which makes the strings stick to the PV cell. The method is going to reduce one step in the production process, replacing the soldering procedure with the lamination of the strings onto the cells. Also, the replacement of lead and silver will spare costs and the environment. To analyse the effects of the novel method on the performance of the cell, the optical properties of the module were investigated by mathematical models and Light Beam Induced Current (LBIC). Also, the electrical properties were compared to the conventional method of soldering by analysing the I-V characteristics. The experiments were done on mini modules. Although the mini module displayed a reflectance of about 5.7 – 6.0% the contribution of the tape only accounted for a maximum of 0.5%. Since the tape only covers a fraction of the cell, this reflectance is negligible. Only 3 modules were successfully analysed, and the electrical properties of the novel method did not differ from the conventional method. To solidify the later a claim a more extensive rapport has to be made. The thesis opens up a new research area where improvements to the novel method can be done. / Det här examensarbetet är gjort på uppdrag av JB Eco Tech. De har utvecklat en ny metod i produktionen av solcells moduler. Syftet med studien är att undersöka metoden som baseras på att fästa transparant tejp med en belagd koppartråd på solcellerna istället för den konventionella metoden som använder sig av lödning. Metoden kommer att reducera ett steg i produktionskedjan genom att utesluta lödningsprocessen. Processen kommer också bidra till en minskning i användandet av silver och bly vilket bidrar till en reducerad kostnad och en minskad miljöpåverkan. För att analysera effekterna av prestandan till följd av den nya metoden så analyserades de optiska egenskaperna med hjälp av matematiska modeller och Light Beam Induced Current (LBIC). De elektriska egenskaperna hos solcells modulerna jämfördes med den konventionella metoden som involverar lödning genom att analysera I-V karakteristiken för de båda metoderna. De ovannämnda experimenten utfördes på miniatyr moduler. Resultaten som erhållits visade på att modulerna hade en reflektans av 5.7 – 6.0% och att tejpen endast stod för max 0.5%. Tejpen täcker endast en bråkdel av cellen därför går det att konstatera att reflektansen som härstammar från tejpen är försumbar. Det innebar att de optiska egenskaperna inte bidrog till en signifikant påverkan på prestandan av modulerna. De elektriska egenskaperna av modulerna påvisade ingen signifikant skillnad mellan de två olika metoderna. För att säkerställa det senare antagandet krävs en utökad studie inom området. Studien har öppnat upp för nya rön som grundas på den nya metoden där det finns utrymme för förbättringar av tejpen.

The Technology today is changing at a fast pace. The growth of computers and telecommunications over the past three decades has been extraordinary. We today are at the point where all technologies related to communication and data transfer are submerging to a common platform. A number of different methods are available for data communication or data transfer. The important factor in all communication setups is to satisfy user demands with low cost and reliability. The area of interest for this thesis is future energy substations and wind mills. In order to make things more straight forward and see its different options and capabilities the focus is on designing and implementing a new energy protocol called Energy Real Time Protocol (eRTP) based on Iyad Real Time Protocol (iRTP) [2]. The protocol is designed to meet the requirements of power and energy networks in terms of sending the energy parameters with VoIP data (optional) among power stations at different locations. Keeping in mind the importance transferring energy parameters in real-time, the presented protocol has built upon small individual algorithms/modules designed for multi-core architecture. Each module is supposed to be processed by an individual core/processor in parallel.

Im Beitrag wird argumentiert, dass sich die Scientific Community reflexiv mit Wissenschafts- und Forschungsethik auseinandersetzen muss. Ergänzend zu institutionalisierten Regeln und Routinepraktiken der Fächer braucht es dafür eine frühestmögliche Aneignung des Themas durch Studierende im Sinne einer „Schlüsselkompetenz“. Jedoch ist für die Disziplinen insgesamt eine systematische Integration als Ausbildungsinhalt nicht erkennbar. Es wird beschrieben, vor welchen Herausforderungen der Einbezug des Gegenstands in der Hochschullehre steht. Dem werden Didaktikbausteine als Potenzial für die systematische Verankerung in Curricula gegenübergestellt. Abschließend werden förderliche Maßnahmen vorgeschlagen.

The aim of this study is to examine how teachers understand interactive methods in history education in secondary and upper secondary school. The study is based on learning theories by Lev Vygotskij, John Dewey and Jean Piaget on how different interactive teaching methods can enhance pupils’ literacy. The method used is a qualitative study which is analyzed inductively through thematic strategy. The findings show how teachers perceive the usefulness in interactive methods and its role in improving literacy in historical concepts.

<p>Cognitive load theory (CLT) lays out a tripartite scheme concerned with how learners cognitively interact with instructional materials during learning and problem solving. Cognitive load refers to the utilization of working memory resources, and CLT designates three types of cognitive load as intrinsic cognitive load, extraneous cognitive load, and germane cognitive load. Intrinsic cognitive load is related to the intrinsic complexity of the material. Extraneous cognitive load is concerned with unnecessary utilization of cognitive resources due to suboptimal instructional design. Germane cognitive load results from processing the intrinsic load and schema acquisition. The expertise reversal effect follows as a consequence of CLT.  </p> <p>The expertise reversal effect (ERE) states that instructional materials that are beneficial to low prior knowledge (LPK) learners may be detrimental to high prior knowledge (HPK) learners. Less guided materials have been shown to reduce extraneous cognitive load for these learners and therefore produce a greater benefit.  </p> <p>In this work we present the development of online instructional modules that deliver content in two distinct styles, differentiated by their use of guiding features. the high level guidance version (HLG) uses guiding features, such as animations and voice narration, which have been shown to benefit LPK learners. Alternatively, guiding features have been shown to be destructive to the learning of HPK students. The low level guidance (LLG) version uses text in place of voice narration and pop-up content in place of continuous animations. Both versions led to a statistically significant improvement from pre-test to post-test. However, both HPK and LPK students showed a preference for the HLG version of the module, contrary to the ERE. Future work will focus on improving the ability to indentify HPK and LPK students, and refining methods for providing optimal instructional materials for these cohorts.  </p> <p>Meanwhile, the use of machine learning is an emerging trend in education. Machine learning has been used in roles such as automatic scoring of essays in scientific argumentation tasks and providing feedback to students in real time. In this work we report our results on two projects using machine learning in education. In one project we used machine learning to predict students’ correctness on a physics problem given an essay outlining their approach to solving the problem. Our overall accuracy in predicting problem correctness given a student’s strategy essay was 80%. We were able to detect students whose approach would lead to an incorrect solution at a rate of 87%. However, deploying this model to provide real-time feedback would necessitate performance improvement. Planned future work on this problem includes hand grading essays to produce a label that reflects the scientific merit of each essay, using more sophisticated models (like Google’s B.E.R.T.), and generalizing to a larger set of problems. </p> <p>In another study, we used data about students’ prior academic behavior to predict academic risk in a first-year algebra based physics course. Their final course grade was used to define their risk category as; B- and above is designated low risk, and C+ and below is designated as high-risk. Using a mix of numerical and category features such as high school gpa, ACT/SAT scores, gender, and ethnicity we were able to predict student academic risk with 75% overall accuracy. Students with a very high grade (A) or students with a very low grade (D,F,W) were identified at a rate 92% and 88% (respectively).</p> <p>Prior work has shown that performance can be greatly increased by including in-class features into the model. Future work will focus on obtaining raw data, rather than using curved scores reported to the university registrar. Also, obtaining more batches of data to improve predictive power with existing models developed in this study.<br> </p>

The study sets out to review various literatures concerning photovoltaic/thermal (PVT) modules for the extraction of electricity and heat, it also reviews different PVT collectors as well as their performance. The study provides an understanding of a system that fully supports ecological society by promoting the use of solar modules from a different scope in future global resolutions. Furthermore, it looks into renewable energy in Sweden, solar energy and PVT systems, operational principles of hybrid PVT collectors, PVT applications, PVT market and legal face of PVT in Sweden among others. Among other social benefits, PVT system contributes enormously to energy savings and energy consumption which in turn lowers CO2 emissions. The review shows that PVT modules can provide homes and industries with 100% renewable electricity and heat that is affordable. This paper adopts systematic literature review, as it allows thorough cross-examination of various publications regarding the subject.

Parents of children with disabilities need accurate information to help them provide tailored services and supports to their families. This is especially true for immigrant Latino families who tend to experience poor overall health and who tend to avoid formal services and supports.Based on input gathered from Latino Parents of children with disabilities, a three module curriculum, "Empowering Families," was developed. Following a cultural appropriateness review of the curriculum and associated measurement instruments, revisions were made to the content and presentation procedure. This was followed by a field test of the curriculum with two groups of Latino parent/caregivers of children with developmental disabilities. Results from the training sessions with both groups indicate that the training resulted in moderate knowledge gains and that self-reported healthy lifestyle behaviors experience minimal improvement. Overall health status was essentially unchanged. Participants rated the content very highly in terms of cultural appropriateness and usefulness.