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In der Ausbildung angehender Lehrkräfte kann fragmentiertes Wissen zu Schwierigkeiten im Umgang mit komplexen Problemsituationen im Unterricht führen. Fähigkeiten im Bereich des vernetzten Denkens, speziell verschiedene Bereiche des Lehrerprofessionswissens miteinander vernetzen zu können, können in komplexen problematischen Unterrichtssituationen hilfreich sein. Um die Fähigkeiten des vernetzten Denkens der Studierenden zu fördern, wird in dieser Studie die Fallmethode im Master of Education der Biologie eingesetzt und in Bezug auf die Förderung der Vernetzungsfähigkeit von Studierenden überprüft. Die Theoriegrundlage der Studie bilden biologiespezifische Kategorien des fachdidaktischen Lehrerprofessionswissens und ein Modell des vernetzten Denkens. In Verbindung mit dem Einsatz von Fällen sollen Fähigkeiten zur theoriebasierten Analyse problematischer Unterrichtssituationen und zur Bildung von Handlungsalternativen, in denen verschiedene Aspekte biologiespezifischen Lehrerprofessionswissens miteinander verknüpft sind, gefördert werden. Die eingesetzten Fälle werden in dieser Studie als theoriebasierte und gleichzeitig praxisnahe Darstellungen komplexer problematischer Unterrichtssituationen verstanden. Die Effektivität der Intervention wird durch eine Interviewstudie sowie durch ein Zwei-Gruppen-Prä-Post-Test, in dem die Studierenden Fälle bearbeiteten, überprüft. Die Ergebnisse zeigen, dass bei beiden Studierendengruppen bereits grundlegende Fähigkeiten im Bereich der theoriebasierten Unterrichtsanalyse vorliegen. Studierende der Interventionsgruppe zeigen zudem eine deutliche Zunahme der Fähigkeiten, Handlungsalternativen für Unterrichtsituationen zu entwickeln, in denen verschiedene fachdidaktische Bereiche miteinander vernetzt sind. Weiterhin konnten vier Fallbearbeitungstypen identifiziert werden. Die Anzahl der Studierenden, die die Kriterien des besonders leistungsstarken Fallbearbeitungstyps erfüllen, nahm bei der Interventionsgruppe deutlich zu. / Teacher education students fragmented knowledge can create difficulties to cope with complex and problematic teaching incidents. The ability to draw on cross-linked thinking, particularly with regard to connect certain aspects of professional teacher knowledge, is helpful in their approach to complex and problematic teaching incidents. To foster the students’ cross-linked thinking ability, the case method of teaching was implemented and evaluated in a module of the masters course in biology teacher education. The theoretical background of the study is based on biology specific pck categories and a model of cross-linked thinking. The central aim of the study is to develop students’ capability in analysing teaching incidents and their capability in creating different action possibilities to deal with teaching incidents, and to identify which different aspects of pck are connected to one another. The multiple intervention study implements a variety of learning cases in a module of the master course in biology teacher education. In this study a case is understood to be based in theory and has to be as close to the practical teaching situation as possible. The effect of the intervention was evaluated by using guided interviews and utilising a two group pre- and post-test design, in which the students analysed test cases. The results show that masters students of the intervention and control group have basic skills in case analysis. Students, particularly in the intervention group, showed an increase in the number of possible ways to deal with case studies of difficult teaching incidents, in which different areas of pck could be cross-linked. Based on students’ test case analyses, four different case-processing types were identified. Furthermore the number of students, whose case analysis ability fell into the strong performance case-processing type, had particularly increased in the intervention group.

<p>Syfte: Syftet är att se om det finns likheter och skillnader mellan Oslobodjenjes, DN:s och New York Times rapportering om massakern som inträffade den 5 februari 1994 på Markalemarknaden i centrala Sarajevo. Syftet är också att se hur journalister från de tre tidningarna förhåller sig till händelsen och de inblandade aktörerna. Avsikten är dessutom att upptäcka om vilken typ av journalistik det handlar om i rapporteringen om den utvalda krigssituationen, samt att se av vilka metoder som tidningarna använder sig av för att uppnå och förmedla ett visst budskap om situationen till sina läsare.</p><p>Metod: kritisk diskursanalys</p><p>Material:</p><p>Oslobodjenje (11-18 februari 1994), Sarajevo/Ljubljana. Europeisk utgåva. Nr. 48</p><p>Dagens Nyheter (6-7 februari 1994)</p><p>New York Times (6-7 februari 1994)</p><p>Huvudresultat:</p><p>Det har visats existera både likheter och skillnader mellan de utvalda tidningarnas rapportering om Markalemassakern. Tidningarna har på ett likadant sätt definierat massakern, samt offer. Dock finns det skillnader mellan tidningarnas förhållningssätt till de inblandade parterna i konflikten, samt till de internationella aktörerna. När det handlar om typen av journalistiken i rapporteringen om Markalemassakern, har det visats existera sida vid sida olika typer av journalistiken. Resultaten har också visat att tidningarna, i produceringen av en bestämd kunskap om situationen, använt sig av nästan likadana metoder. Dessa metoder har även lett till insikten om att tidningarna strävat efter att visa och bevisa existensen av den ”objektiva” nyhetsförmedlingen. Dock har enbart New York Times lyckats bekräfta sin profil som ”oberoende” och ”objektiv” förmedlare av situationen på Markalemarknaden. Hos andra två tidningar har det varit svårt att bekräfta en sådan status, då Oslobodjenjes rapportering visade följa en bosnisk politisk linje, medan det hos Dagens Nyheter uppenbarades ett NATO-perspektiv.</p>

Syfte: Syftet är att se om det finns likheter och skillnader mellan Oslobodjenjes, DN:s och New York Times rapportering om massakern som inträffade den 5 februari 1994 på Markalemarknaden i centrala Sarajevo. Syftet är också att se hur journalister från de tre tidningarna förhåller sig till händelsen och de inblandade aktörerna. Avsikten är dessutom att upptäcka om vilken typ av journalistik det handlar om i rapporteringen om den utvalda krigssituationen, samt att se av vilka metoder som tidningarna använder sig av för att uppnå och förmedla ett visst budskap om situationen till sina läsare. Metod: kritisk diskursanalys Material: Oslobodjenje (11-18 februari 1994), Sarajevo/Ljubljana. Europeisk utgåva. Nr. 48 Dagens Nyheter (6-7 februari 1994) New York Times (6-7 februari 1994) Huvudresultat: Det har visats existera både likheter och skillnader mellan de utvalda tidningarnas rapportering om Markalemassakern. Tidningarna har på ett likadant sätt definierat massakern, samt offer. Dock finns det skillnader mellan tidningarnas förhållningssätt till de inblandade parterna i konflikten, samt till de internationella aktörerna. När det handlar om typen av journalistiken i rapporteringen om Markalemassakern, har det visats existera sida vid sida olika typer av journalistiken. Resultaten har också visat att tidningarna, i produceringen av en bestämd kunskap om situationen, använt sig av nästan likadana metoder. Dessa metoder har även lett till insikten om att tidningarna strävat efter att visa och bevisa existensen av den ”objektiva” nyhetsförmedlingen. Dock har enbart New York Times lyckats bekräfta sin profil som ”oberoende” och ”objektiv” förmedlare av situationen på Markalemarknaden. Hos andra två tidningar har det varit svårt att bekräfta en sådan status, då Oslobodjenjes rapportering visade följa en bosnisk politisk linje, medan det hos Dagens Nyheter uppenbarades ett NATO-perspektiv.

In this paper, a discussion and analysis on the Swedish participation  in the UN-mission in the Balkan conflict versus the reporting from the Swedish news press Dagens Nyheter (DN) of the same action is held. From a ground in survey questions to Swedish soldiers that took part in the conflict ,what they thought of the conflict and what got reported back to the Swedish civilians via the press and their differences is later held. A question in the survey also treats what the soldiers think got changed in the Swedish Armed Forces due to their actions in the conflict and what the soldiers thought of the view in the 1990s, national and international, on the Swedish Armed Forces. This survey and the articles  from DN that is analyzed is the ground in this papers issues, discussion and results. The paper overall and later the analysis is based on a theory in Oral history taken of Malin Thor's previous researches in the field and also strengthened with other researchers in the same field of studies.   The title to this paper is from the English press reporting about the Swedes taking charge of the UNPROFOR-mission in the Balkan conflict and is about the Colonel Ulf Henricsson, commander of the UN Nordic battalion (NordBat2) in central Bosnia and his firm hand and authority against the local warlords. Later the title went famous international and a lot of different newspapers used it as a headline when reporting about the Swedish soldiers acting aggressively and firmly towards the war-criminals when protecting civilians and their properties in Bosnia.

Die Förderung epistemischer Überzeugungen gilt als wichtige Aufgabe in der Lehrerbildung. Insbesondere im bildungswissenschaftlichen Begleitstudium tendieren Studierende jedoch zu ungünstigen Überzeugungen: Bildungswissenschaftliches Wissen wird im Vergleich zu fachwissenschaftlichem Wissen als wenig systematisiert, subjektiv und kaum praxisrelevant beurteilt. Wie Studierende dabei unterstützt werden können, angemessene Überzeugungen zum Wissen in den Bildungswissenschaften zu entwickeln, ist empirisch noch unzureichend untersucht. Aus diesem Grund wurden literaturgestützt drei Kurzinterventionen entwickelt, die auf je spezifischen Förderstrategien gründen: (1) Direkt-explizite Adressierung von epistemischen Überzeugungen, (2) indirekt-implizite Adressierung und (3) Kombination aus direkten und indirekten Förderansätzen. Die Eignung der drei Interventionen wurde in einem quasi-experimentellen Mixed-Methods-Design in zwei Teilstudien untersucht. Die quantitative Teilstudie umfasste eine Veränderungsmessung. Es konnte gezeigt werden, dass sich die Studierenden aus der direkten und der kombinierten Intervention tendenziell in Richtung reflektierter Überzeugungen weiterentwickelt haben. Die indirekte Intervention blieb dagegen wirkungslos. Die qualitative Teilstudie umfasste die Analyse von Follow-Up-Interviews, die im Nachgang der Interventionen mit teilnehmenden Studierenden geführt wurden. Die Ergebnisse stützten erstens die Befunde aus der quantitativen Teilstudie, wobei ein besonderes Veränderungspotenzial für die kombinierte Intervention deutlich wurde. Zweitens konnten die zugrunde liegenden Wirkweisen der verschiedenen Interventionen herausgearbeitet werden. Drittens konnten weiterführende Erkenntnisse zu den grundlegenden Veränderungsmechanismen epistemischer Überzeugungen erzielt werden. Das bestehende Veränderungsmodell epistemischer Überzeugungen konnte weiterentwickelt und um individuelle Faktoren ergänzt werden. / Fostering epistemic beliefs is considered an important task in teacher education. However, especially in educational science, preservice teachers tend to hold unfavorable epistemic beliefs: Compared to knowledge in other disciplines, educational knowledge is perceived to be less systematic, subjective and irrelevant for classroom practice. However, how students can be supported in developing adequate beliefs about educational knowledge has not been sufficiently explored. For this reason, three short-term interventions were designed, each based on specific approaches to elicit changes in students’ epistemic beliefs (1) direct-explicit approach, (2) indirect-implicit approach, and (3) combination of direct and indirect approaches. The effectiveness of the three interventions was investigated in a quasi-experimental mixed-methods design in two studies. In the quantitative study a measurement of change was performed. It was shown that students from the direct and combined intervention groups tended to develop more adequate beliefs. The indirect intervention, in contrast, can be considered ineffective. The qualitative study involved the analysis of follow-up interviews conducted with participating students after the interventions. First, the results supported the findings from the quantitative study, highlighting a particular potential for change in the combined intervention. Second, the underlying ways in which the interventions stimulated change were identified. Third, further insights into the underlying mechanisms of epistemic change were obtained. The existing model of epistemic change was refined and complemented by individual factors that can influence the process of epistemic change.

Historically ceramic crystal laser material has had disadvantages compared to single crystal laser material. However, progress has been made in the last decade and a half to overcome the disadvantages associated with ceramic crystal. Today, because of the promise of ceramic crystal as a high power laser material, investigation into its properties, both physical and optical, is warranted and important. Thermal expansion was measured in this thesis for Nd:YAG (yttrium aluminum garnet) ceramic crystal using an interferometric method. The interferometer employed a spatially filtered HeNe at 633 nm wavelength. Thermal expansion coefficients measured for the ceramic crystal samples were near the reported values for single crystal Nd:YAG. With a similar experimental setup as that for the thermal expansion measurements, dn/dT for ceramic crystal Nd:YAG was measured and found to be slightly higher than the reported value for single crystal. Depolarization loss due to thermal gradient induced stresses can limit laser performance. As a result this phenomenon was modeled for ceramic crystal materials and compared to single crystals for slab and rod shaped gain media. This was accomplished using COMSOL Multiphysics, and MATLAB. Results indicate a dependence of the depolarization loss on the grain size where the loss decreases with decreased grain size even to the point where lower loss may be expected in ceramic crystals than in single crystal samples when the grain sizes in the ceramic crystal are sufficiently small. Deformation-induced thermal lensing was modeled for a single crystal slab and its relevance to ceramic crystal is discussed. Data indicates the most notable cause of deformation-induced thermal lensing is a consequence of the deformation of the top and bottom surfaces. Also, the strength of the lensing along the thickness is greater than the width and greater than that due to other causes of lensing along the thickness of the slab. Emission spectra, absorption spectra, and fluorescence lifetime were measured for Nd:YAG ceramic crystal and Yb:Lu2O3 ceramic crystal. No apparent inhomogeneous broadening appears to exist in the Nd:YAG ceramic at low concentrations. Concentration and temperature dependence effects on emission spectra were measured and are presented. Laser action in a thin disk of Yb:Y2O3 ceramic crystal was achieved. Pumping was accomplished with a fiber coupled diode laser stack at 938 nm. A slope efficiency of 34% was achieved with maximum output energy of 28.8 mJ/pulse.

Size exclusion chromatography is the method of choice for characterizing molecular weights and molecular weight distributions of polymers. An important advancement in SEC is multidetection SEC which includes multi-angle laser light scattering, viscometry, refractive index and UV spectroscopy to analyze block and graft copolymers as well as polymers with oligomeric molecular weights. Oligomeric molecular weights present special challenges since the light scattering and viscosity detectors are more sensitive to higher molecular weights and both detectors have low molecular weight threshold values. The molecular weights and distributions of poly(2-ethyl-2-oxazoline) oligomers and block copolymers as well as poly(2-ethyl-2-oxazoline) were investigated by SEC using multiple detectors. Both a universal calibration method and light scattering were used to determine molecular weights and molecular weight distributions. The solvent was N-methylpyrrolidone that contained 0.05M LiBr used to minimize interactions among the polymers and solvent. SEC was used to establish that the diblock copolymers had heterogeneous compositional distributions. The low molecular weights of the diblock and homopolymer made it necessary to use the universal calibration method with combined refractive index and viscometry detectors to determine absolute molecular weights. / Master of Science

Este trabalho discutiu o estudo da inferência de carregamento e a reconstrução fratográfica da taxa de propagação da trinca por fadiga em histórias de vôos simulados do tipo Twist, mini-Twist, Falstaff e mini-Falstaff. O material estudado foi uma liga de alumínio de grau aeronáutico SAE-AMS 7475 T7351 na qual foram obtidas as propriedades mecânicas a partir dos ensaios de tração e dureza, análise química, metalográfica. Foram realizados ensaios de amplitude constante de carregamento em corpos de prova com geometria tipo C(T) extraídos de um bloco e ensaios de amplitude variável em corpos de prova com geometria tipo M(T) extraídos de uma placa. Corpos de prova do tipo C(T) foram extraídos da orientação L-T e T-L, à temperatura ambiente com diferentes espessuras para a realização de ensaios de propagação de trinca por fadiga (da/dN vs. &#916K) com distintos valores de razão de carregamento,R (0,1;0,3; 0,5; 0,7 e 0,8) de acordo com a norma ASTM-E647 (1993). Foram realizados dois tipos de ensaios de fadiga com amplitude constante de carregamento. Primeiro, o ensaio com &#916P constante para obtenção dos dados dos estágios II e III das curvas da/dN vs. &#916K para distintos valores de R e, posteriormente, o ensaio com &#916K constante e R crescente para ser utilizado no estudo da inferência de carregamento de amplitude constante a partir da relação entre a morfologia da estria, H/s e a razão de carregamento R. Adicionalmente foram realizados ensaios de tenacidade à fratura, nas direções L-T e T-L, conforme a norma ASTME1820 (1999). As taxas de propagação macroscópica e microscópica foram comparadas e boas correlações foram obtidas para um intervalo entre 0,1 a 1,0 &#956m/ciclo, mesmo com distintos R. Através da técnica proposta por Berkovitz (1995), o espectro de carregamento foi estimado para distintos valores de R, através da técnica de parametrização do fator K e os resultados foram comparados ao espectro de carregamento real imposto pela máquina de ensaio. Após os ensaios de amplitude constante de carregamento foram realizados ensaios de amplitude variável com a aplicação em corpos de prova M(T) de espectros de vôos simulados padronizados pela NLR do tipo Twist e Falstaff e seus vôos reduzidos, mini-Twist e mini- Falstaff, em uma máquina servohidráulica de ensaios dinâmicos. A partir destes ensaios notou-se que suprimir os vôos com os carregamentos menos severos influencia muito a vida da propagação da trinca de fadiga, quando vôos simulados do tipo Twist e mini-Twist, fato este não observado para o Falstaff e mini-Falstaff. Foi possível observar também o efeito da aceleração e desaceleração da trinca por fadiga observando os gráficos de d2a/dvôo vs. a obtidos dos ensaios de amplitude variável. Foi realizado um estudo da superfície de fratura do CP05 por meio da técnica fractográfica do reconhecimento de blocos marcadores sendo possível mostrar uma satisfatória reconstituição da taxa de propagação da trinca por fadiga de vôo simulado do tipo Falstaff por meio de medidas das marcações na superfície de fratura dos vôos mais severos, realizadas em imagens obtidas por MEV. / The loading inference and the fractographic reconstruction of fatigue crack propagation rate in simulated flight stories, as Twist, mini-Twist, Falstaff and mini-Falstaff were investigated in this work. The studied material was an aluminum alloy SAE-AMS 7475 T7351. Tensile and hardness tests were carried out in order to determine mechanical properties, as well as chemical and microstructure analysis of the material. C(T) specimens were extracted from a block of material for constant amplitude load testing and M(T) specimens were extracted from a plate and were tested in variable amplitude loading. The curves (da/dN vs. &#916K) for constant-amplitude loading were obtained from fatigue crack propagation tests performed in L-T and T-L directions in C(T) specimens for R (0.1; 0.3; 0.5; 0.7 and 0.8), at room temperature, according to ASTM-E647 (1993). Two different constant loading fatigue tests were performed. At constant &#916P and distinct values of R for obtaining data of stages II and III of da/dN - &#916K curves; and at constant &#916K and increasing the R ratio to be used in the inference of constant amplitude loading in the relation of H/s striation morphology (obtained from fractographic images) and the loading ratio, R. Additionally, fracture toughness tests were executed in T-L and L-T directions, according to ASTM-E1820 (1999). The macroscopic and microscopic fatigue crack propagations were compared and good correlation was obtained for the range 0.1-1.0 &#956m/cycle, for all R values. By using the K factor parametrization method, Berkovitz (1995), the loading spectrum was estimated for the distinct R-values and the results were compared to the actual spectrum imposed by the test machine. Variable amplitude tests were performed in M(T) specimens by applying simulating flight spectra normalized by NLR, as Twist, mini-Twist, Falstaff and mini-Falstaff, in a servohydraulic test machine MTS, in which a Flextest GT controller was coupled. The suppression of less severe loading flights showed a great influence in fatigue crack propagation life, in simulated flight tests Twist and mini-Twist, but not in Falstaff and mini-Falstaff. The acceleration and slowing down of fatigue crack were observed in the d2a/dflight - a curve obtained from variable loading tests. The fractured surfaces of some samples were examined by the fractographic technique of blocking marks recognition. A good reconstitution of fatigue crack propagation rate of a simulated flight like Falstaff was obtained by the measurements of marks in the fracture surfaces of the more severe flights, in MEV images.