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Visual Stimuli for Charity : A field experiment about recycling and charitable givingMarklund, Victor January 2010 (has links)
Never before has the interest for charity been greater. At this writing, U.S. charities have collected nearly one billion U.S. dollars (!) only in the aid for the disaster victims in Haiti.But can you get people to give even more? Are there yet unexplored market in which charitable organizations still have growth potential? Traditional economic theory which is based in individuals' rational behavior and self-utility maximization has a hard time to explain the phenomenon of charitable donations. But relatively new research can possibly connect the theory and the phenomenon through the theorem of warm-glow in why people actually donate money anonymously and indirectly to people they never met or will ever know who made the donation. This thesis will examine whether or not a small change in the environment could influence individuals to donate more money and / or more frequently. The study was conducted as a field experiment at an ICA store deposit station where people are faced with the choice to donate their deposit to the Swedish Red Cross instead of getting a voucher for themselves. The obtained results shows a statistically significant difference between the donation of the pledge of over 13 percentage more in the presence of a visual stimulus, more specifically a picture of a poor boy drinking clean water from a tap. That results in a doubling in nominal amounts of donations for the charity. Moreover, I find that people who already before the experiment are sympathetic to donating the pledge do so to a greater extent than people who were not. Neither sex nor age seemed to affect the results in any way.
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Postmating Sexual Selection and its Role in Population Divergence in BeetlesFricke, Claudia January 2006 (has links)
Speciation is the process describing the formation of new species and is at the heart of evolutionary biology. According to the biological species concept only reproductively isolated forms are regarded good species. This thesis aims at identifying evolutionary processes that cause population divergence and, ultimately, speciation. Natural and sexual selection are two major candidates driving changes in traits that could render populations reproductively incompatible. In recent years, biologists have recognized that most animal species are polygamous. Therefore, sexual selection does not end at mating but continues to include interactions between individuals after mating has occurred but before zygote formation. Male-male sperm competition and cryptic female choice are two main forms of postmating sexual selection shaping reproductive traits like behaviour. The studies presented in this thesis focus on laboratory experiments attempting to identify the role of postmating sexual selection in causing reproductive divergence across populations in beetles. The majority of studies were performed using a Bruchid beetle, Callosobruchus maculatus, a common, worldwide pest on stored leguminose seeds. I used two major methodological approaches. One approach seeks to identify the traces left by past selection among extant conspecific populations, by assessing the pattern of female reproductive responses to mating with males of decreasing relatedness. Second, I used a selection experiment to disentangle the joint effect of natural and sexual selection acting simultaneously on diverging replicated selection lines. In general, these experiments revealed that postmating sexual selection can be a powerful engine of incipient divergence between allopatric populations. Changes in traits underlying variables such as female reproductive output, female mating rate or male success in sperm competition evolved rapidly and could in some cases effectively reduce gene flow between conspecific populations. While postmating sexual selection per se can drive divergence, I found that interactions with natural selection can limit divergence in reproductive characters. Sexual selection tended to reinforce natural selection under strong directional selection. In contrast, sexual selection inflicted a reproductive load on populations under weak natural selection. Thus, the joint effects of natural and sexual selection on allopatric populations are non-trivial and should be considered in greater detail in future studies of early divergence.
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Tid för reformering : Försöksverksamheten med slopad timplan i grundskolanRönnberg, Linda January 2007 (has links)
In 1999, the Swedish Parliament decided to launch an experiment to test the idea of replacing, at the compulsory educational level, the national time schedule with localized control of schedules. This was in keeping with strategies of deregulation, decentralisation and increased local autonomy that had dominated Swedish education policy, particularly since the 1990s. The aim of the thesis is to describe and analyse the initiation, decision, implementation and consequences of this experiment The analytical framework combines several different approaches and theories from the literature on public policy and policy analysis. The framework encompasses four dimensions, which cover the experiment’s origins, local application in the classroom setting and consequences. On the empirical level, findings are based on interviews with 32 municipal school directors, and head teachers, teachers and pupils in three schools participating in the experiment, as well as written sources from schools, municipalities, and the national level. The thesis shows that the policy problem the experiment was intended to resolve was represented in an inconsistent manner: On the one hand, the experiment was perceived as a driving force for change; on the other hand, it was seen as legitimising a change that had already taken place. Furthermore, the experiment was formulated in vague terms, which accorded far-reaching discretionary space to the schools. The program’s causal theory expressed by the policy makers was complex, containing a multifaceted chain of presumptions on a range of activities and processes through which the experiment ultimately would lead to improved opportunities for pupils to reach the educational objectives. Empirically, this prediction proved to be invalid as student achievement did not increase. The degree of implementation at the local level varied according to the comprehension, capability and willingness of those involved to carry out the experiment. The courses of action taken by the schools frequently could have been undertaken within the existing legislative framework, as they mostly concerned new ways of working and organising staff and pupils. An assessment of the objectives attained showed that, even if elements of developmental work corresponding to the direction stated in the policy documents were observed, the experiment did not emerge as the primary explanatory factor for this result Thus, the net impact of the experiment can be questioned. If judged against the criterion of adaptiveness, the results are more successful than if the experiment is assessed according to goal-attainment and the validity of the program theory. The experiment was found to integrate, alter and accommodate itself readily to local needs. The thesis illustrates the complexity of formulating and implementing policy in a decentralised context and points to important aspects in the historical background of the programme, which often tend to be overlooked when policy is analysed and discussed. At the same time, the study sheds light on the significant role played by street-level implementation actors in the educational context.
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Ultracold rubidium atoms in periodic potentialsSaers, Robert January 2008 (has links)
This thesis includes both experimental and theoretical investigations, presented in a series of eight papers. The experimental part ranges from the construction procedures of an apparatus for Bose-Einstein condensates, to full scale experiments using three different set-ups for ultracold atoms in optical lattices. As one of the main themes of the thesis, an experimental apparatus for production of Bose-Einstein Condensates is under construction. A magneto-optically trapped sample, hosting more than 200 million 87Rb atoms, have successfully been loaded into a magnetic trap with high transfer rate. The lifetime of the sample in the magnetic trap is in the range of 9 s, and the atoms have been shown to respond to evaporative cooling. The experiment is ready for optimization of the magnetic trap loading, and evaporative cooling parameters, which are the final steps for reaching Bose-Einstein condensation. The set-up is designed to host experiments including variable geometry optical lattices, and includes the possibility to align laser beams with high angular precision for this purpose. The breakdown of Bloch waves in a Bose-Einstein condensate is studied, attributed to the effect of energetic and dynamical instability. This experimental study is performed using a Bose-Einstein condensate in a moving one-dimensional optical lattice at LENS, Florence Italy. The optical lattice parameters, and the thermal distribution of the atomic sample required to trigger the instabilities, are detected, and compared with a theoretical model developed in parallel with the experiments. In close connection with these one-dimensional lattice studies, an experimental survey to characterize regimes of superradiant Rayleigh scattering and Bragg scattering is presented. Tunneling properties of repulsively bound atom pairs in double well potentials are characterized in an experiment at Johannes Gutenberg University, Mainz Germany. A three-dimensional optical lattice, producing an array of double wells with tunable properties is let to interact with a Bose-Einstein condensate. Pairs of ultracold atoms are produced on one side in the double wells, and their tunneling behavior, dependent on potential barrier and repulsion properties, is studied. A theoretical study of the crossover between one- and two-dimensional systems has been performed. The simulations were made for a two-dimensional array of atoms, where the behavior for different tunneling probabilities and atom-atom repulsion strengths was studied. Scaling relations for systems of variable sizes have been examined in detail, and numerical values for the involved variables have been found.
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Peter Weiss filmer : från de korta små lekfulla kopparslagen till kommersiell långfilmsdebut: filmer - filmidéer - utkast / Films by Peter WeissBengtsson, Jan Christer January 2010 (has links)
This doctoral thesis deals with Peter Weiss’ (1916-1982) films and some of his never finished attempts. The focus is in general on Weiss’ film work activities in the 1950’s, when film held the very central place in his works of art. The intention has been to interrogate what short films Peter Weiss made and to find out the meaning and the role of film in the life of the artist Peter Weiss. The conclusion is that Peter Weiss fought with personal difficulties in expressing himself in a language — a language of words and a language of signs — because it is assumed that Peter Weiss carried a very strong will to become an author. In order to “conquer the words” Weiss exercised himself in describing all kinds of worlds — an interior one as well as an exterior one. That explains why he dealt with surrealist psychological subjects and documentary forms while making films.
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Informationsöverflöd på den svenska fondmarknaden? / Information overload on the Swedish investment fund market?Bank, Joakim, Jansson, Eric January 2009 (has links)
No description available.
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Barns lärande – Om trädWerme, Linda January 2008 (has links)
Med naturen och Learning study modellen som inspirationskällor har jag arbetat med tema träd under två veckor på en förskola med barn i åldrarna 3 – 6 år. För att tydligt kunna synliggöra barnets lärande har för- och eftertester varit en del av metodarbetet. Testerna genomfördes med hjälp av intervjuer. Barnen fick även rita teckningar av ett träd både vid förtestet och eftertestet. Detta som ett ytterligare komplement för att kunna se deras kunskapsutveckling. Under dessa två veckor mellan för- och eftertestet deltog barnen i olika aktiviteter på ett lekfullt och lustfyllt sätt. Genom hela arbetet användes en handdocka i form av en ekorre. Handdockan gjorde att även de barn som var lite reserverade vågade prata och ställa frågor. Vidare användes även olika lekar såsom tillexempel memory och Kims lek. Utifrån den här studien med inspiration från Learning study metoden kan man konstatera att barnens kunskap inom temat träd har utvecklats.
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Aeroelastic and Flight Dynamics Analysis of Folding Wing SystemsWang, Ivan January 2013 (has links)
<p>This dissertation explores the aeroelastic stability of a folding wing using both theoretical and experimental methods. The theoretical model is based on the existing clamped-wing aeroelastic model that uses beam theory structural dynamics and strip theory aerodynamics. A higher-fidelity theoretical model was created by adding several improvements to the existing model, namely a structural model that uses ANSYS for individual wing segment modes and an unsteady vortex lattice aerodynamic model. The comparison with the lower-fidelity model shows that the higher-fidelity model typical provides better agreement between theory and experiment, but the predicted system behavior in general does not change, reinforcing the effectiveness of the low-fidelity model for preliminary design of folding wings. The present work also conducted more detailed aeroelastic analyses of three-segment folding wings, and in particular considers the Lockheed-type configurations to understand the existence of sudden changes in predicted aeroelastic behavior with varying fold angle for certain configurations. These phenomena were observed in carefully conducted experiments, and nonlinearities - structural and geometry - were shown to suppress the phenomena. Next, new experimental models with better manufacturing tolerances are designed to be tested in the Duke University Wind Tunnel. The testing focused on various configurations of three-segment folding wings in order to obtain higher quality data. Next, the theoretical model was further improved by adding aircraft longitudinal degrees of freedom such that the aeroelastic model may predict the instabilities for the entire aircraft and not just a clamped wing. The theoretical results show that the flutter instabilities typically occur at a higher air speed due to greater frequency separation between modes for the aircraft system than a clamped wing system, but the divergence instabilities occur at a lower air speed. Lastly, additional experimental models were designed such that the wing segments may be rotated while the system is in the wind tunnel. The fold angles were changed during wind tunnel testing, and new test data on wing response during those transients were collected during these experiments.</p> / Dissertation
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The Relationship between Decision Making Deficits and Drug Addiction: A Neurobiological ApproachJohnson, Alex R 01 January 2013 (has links)
Drug addiction is a complex behavioral disorder that has been extensively studied in an attempt to uncover its underlying biological mechanisms. This paper contributes to the literature on addiction by demonstrating that addiction is a result of an improperly functioning decision making process. The areas of the brain that are most implicated in decision making demonstrate significant overlap with those areas most affected by addiction. Specifically, the limbic structures of the brain (amygdala, basal ganglia, and mesolimbic reward pathway) and the prefrontal cortices (orbitofrontal cortex, dorsolateral prefrontal cortex, and ventromedial prefrontal cortex) are discussed in relation to their involvement in prominent theories of decision making such as Prospect Theory and the Somatic Marker Hypothesis. This paper will then use the above knowledge regarding the specific brain mechanisms that control decision making and apply it to neurobiological theories of addiction. The view that addiction is a behavioral disorder that results primarily from a degradation of the brain mechanisms involved in decision making processes is important to consider because it can help provide a concrete approach to developing more individualized and effective treatment programs in the future.
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Evidence pour une nouvelle particule semblable au boson de Higgs du modèle standard et se désintégrant en quatre leptons dans l'expérience CMSPlestina, Roko 21 February 2013 (has links) (PDF)
Cette thèse présente la mise en évidence dans l'expérience CMS d'un nouveau boson dans la voie H→ZZ et la contribution à la découverte de ce nouveau boson à une masse proche de 125 GeV dans l'expérience CMS au CERN. La mesure des propriétés est passée en revue. Les résultats sont obtenus par une analyse inclusive du canal H→ZZ→ 4l , i.e. où chacun des bosons Z se désintègre en une paire de leptons (l ), électrons ou muons. La recherche du boson de Higgs couvre toutes les hypothèses de masse dans le domaine 110 < mH < 1000 GeV. L'analyse utilise les données de collisions proton-proton enregistrées par le détecteur CMS au collisionneur LHC, correspondants à des luminosités intégrées de 5.1 fb^−1 a sqrt(s) = 7 TeV et 12.2 fb^−1 at sqrt(s) = 8 TeV. Le nouveau boson est observé avec une signifiance statistique au-desus du bruit de fond attendu de 4.5 écarts standards. L'intensité du signal μ, normalisé à l'attendu pour le boson de Higgs du modèle standard, est mesuré à une valeur de μ = 0.80+0.35-0.28 a 126 GeV. Une mesure précise de la masse du nouveau boson a été effectué et donne 126.2 ± 0.6 (stat) ±0.2 (syst) GeV. L'hypothèse d'un boson scalaire 0+ est en accord avec l'observation. Les données expérimentales défavorisent l'hypothèse pseudoscalaire 0− avec CLs de 2.4%. Aucun autre excès significatif n'est observé, et des limites supérieures d'exclusions sont obtenues à 95% de niveau de confiance pour les domaines 113-116 GeV et 129-720 GeV, alors que la domaine d'exclusion attendue en absence du boson de Higgs est de 118-670 GeV. Pour cette thèse, une emphase particulière a été mis sur l'isolation des leptons. L'isolation des leptons fait parties des observables clefs sur le chemin de la découverte. En même temps, l'isolation est très sensible aux conditions pile-up de la machine LHC. Cette thèse établit une méthode robuste qui permet de marginaliser l'effet de pile-up sur l'isolation. La méthode est maintenant utilisée à travers les différentes analyses de CMS. Une attention particulière a également été mis sur les mesures de l'efficacité de l'identification des leptons, l'isolation et le paramètre d'impact directement à partir de données à l'aide désintégrations leptoniques de boson Z . Les mesures ont été utilisées pour les corrections finales appliquées aux leptons lors du calcul de la signifiance statistique de l'excès des événements à quatre leptons.
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