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121.
Ulrike Meyer Stump 《History of Photography》2013,37(3):290-292
Abstract ‘Made in Switzerland. The Photography Collections of the Swiss Confederation’ was an exhibition organized by the Swiss Federal Office of Culture and hosted by the Musee de l'Elysee in Lausanne in 1997. The exhibition officially confIrmed that the Swiss are at last beginning to recognize the value of their national photographic heritage. Official efforts concerning the conservation of photographs have until recently consisted of the preservation of architectural documents by the Federal Archive for the Protection of Monuments in Bern and of the rather limited activities of the Swiss Foundation of Photography, located in Zurich since 1971, which has primarily focused on professional reportage. Two private collectors, however, have been discreetly active for over three decades amassing thousands of photographs, albums, cameras, and books on photography, thus safeguarding material that might have been lost or destroyed due to the general lack of interest shown by public institutions. Michele and Michel Auer, two photography encyclopaedists living in Hermance on Lake Geneva, and Ruth and Peter Herzog in Basle have assembled the two largest private photography collections in Switzerland. But whereas collecting is an extension of the professional work of the Auers, Ruth Herzog-Wyss, a book dealer, and Peter Herzog, a lawyer and art expert, are amateur collectors. 相似文献
122.
Surface defects strongly influence the surface chemistry of metal oxides, and a detailed picture of defect structures may help to understand reactivity and overall materials performance in many applications. We report first-principles calculations of step edges, the most common intrinsic defects on surfaces (and probably the predominant ones on nanoparticles). We have determined the structure, energetics, and chemistry of step edges on the (101) surface of TiO(2) anatase, an important photocatalytic material. Scanning tunnelling microscopy measurements of step-edge configurations and the contrast in atomically resolved images agree remarkably well with the theoretical predictions. Step-edge formation energies as well as the adsorption energies of water scale with the surface energy of the step facet, a trend that is expected to generally hold for metal oxide surfaces. Depending on the terrace/step configuration, this can lead to a situation where a step is less reactive than the flat terrace. 相似文献
123.
Gen Li Ulrike K. Müller Johan L. van Leeuwen Hao Liu 《Journal of the Royal Society Interface》2014,11(101)
Fish larvae may intercept their own wake during sharp turns, which might affect their escape performance. We analysed C-starts of larval zebrafish (Danio rerio, Hamilton, 1822) using a computational fluid dynamics approach that simulates free swimming (swimming trajectory is determined by fluid forces) by coupling hydrodynamics and body dynamics. The simulations show that fish may intercept their own wake when they turn by 100–180°. During stage 1 of a C-start, the fish generates a strong jet at the tail that is shed into the wake. During stage 2, the fish intercepts this wake. Counterfactual simulations showed that wake interception increased the lateral force on the fish and reduced the fish''s turning angle by more than 5°. Wake interception caused no significant acceleration tangential to the trajectory of the fish and did not affect total power output. While experimental and simulation evidence suggests that fish larvae can either undershoot or intercept but not overshoot their wake, our simulations show that larger fish might be able to avoid intercepting their wake by either under- or overshooting. As intercepting its own wake modifies the fish''s escape trajectory, fish should account for this effect when planning their escape route. 相似文献
124.
In most studies using informant reports of personality, the informants are recruited by the targets. Such informants may tend to like the targets and thus portray them in specific ways (e.g., too positively). Study 1 (N = 403) demonstrated the necessity to distinguish between “liking” and “knowing” in studying the relationships between informants and targets. Informants who liked their targets better described them more positively (i.e., as being more extraverted, agreeable, open, conscientious, and less neurotic). The association between personality ratings and liking was moderated by item evaluativeness. Liked targets were also described as being more similar to each other (range restriction), which would lower correlations of informant ratings of personality with external variables. Study 2 (N = 90) used a within-subjects design to disentangle actual personality differences between targets (substance) from the informants’ specific views on the targets (style). Ninety informants were asked to nominate targets they did not like. These targets then nominated informants of their own choice. Target-nominated informants liked the targets very much and described the targets’ personalities very positively and in ways that were highly redundant with the average target’s self-rating. There was evidence that lower liking may be associated with better accuracy. Higher subjective levels of knowing were not associated with better interrater agreement but with a greater willingness to describe targets negatively. Implications for the field of recruiting are discussed. Where possible, the choice of informants and referees should be made independent of the targets’ preferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
126.
It is known that austenite strength determines the morphology of the new phase during martensitic transformation. As the strength of austenite influences the growth of a martensite crystal, i.e. the movement of the austenite/martensite interface, a correlation between strength of the parent phase and Ms has to exist. Ms depends on thermodynamical and mechanical properties of the alloys. To distinguish the individual variables, austenite strength was changed by different hardening mechanisms: solid solution hardening, plastic deformation or both. 相似文献
127.
Christina Schwind Jürgen Buder Ulrike Cress Friedrich W. Hesse 《Computers & Education》2012,58(2):787-796
The Web is a perfect backdrop for opinion formation as a multitude of different opinions is publicly available. However, the different opinions often remain unexploited: Learners prefer preference-consistent over preference-inconsistent information, a phenomenon called confirmation bias. Two experiments were designed to test whether technologies such as recommender systems can be used to overcome this bias. The role of preference-inconsistent recommendations was explored by comparing their influence to a condition with preference-consistent recommendations and to a control condition without recommendations. In Study 1, preference-inconsistent recommendations led to a reduction of confirmation bias and to a more moderate view of the controversial topic of neuro-enhancement. In Study 2, we found that preference-inconsistent recommendations stimulated balanced recall and divergent thinking. Together these studies showed that preference-inconsistent recommendations are an effective approach for reducing confirmation bias and stimulating divergent thinking. In conclusion, future research and practical implications are discussed. 相似文献
128.
While a growing number of travelers engages in consumer-generated media (CGM) use and creation, the gap between the number of users and the number of actual content creators remains large. It is important to find out what drives this minority of creators and what makes them different from those who only use CGM. Personality has been found to be a particularly influential trait that predicts behavior. The influence of personality on travel CGM creation was investigated and the results indicate that travelers’ personality traits significantly influence perceived barriers to content creation, motivations to engage in CGM creation, and specific creation behaviors. Contributions and implications are discussed from both a theoretical and a practical perspective. 相似文献
129.
Whereas the contribution from renewable energies in the electrical power market is increasing rapidly, similar progress in the heat market is yet to be made. A prerequisite for progress is the development of innovative support instruments that transcend the usual support through public subsidies or tax reductions. We present an overview of the various classes of possible instruments. Some particularly interesting instruments will be selected and evaluated, comparing them qualitatively and quantitatively for the case of Germany. The most favourable model is found to be a new, allocation-financed1 model known as the Bonus Model. This model will be described in more detail. 相似文献
130.
This research proposes a model that predicts the effect of the anode diffusion layer and membrane properties on the electrochemical performance and methanol crossover of a direct methanol fuel cell (DMFC) membrane electrode assembly (MEA). It is an easily extensible, lumped DMFC model. Parameters used in this design model are experimentally obtainable, and some of the parameters are indicative of material characteristics. The quantification of these material parameters builds up a material database. Model parameters for various membranes and diffusion layers are determined by using various techniques such as polarization, mass balance, electrochemical impedance spectroscopy (EIS), and interpretation of the response of the cell to step changes in current. Since the investigation techniques cover different response times of the DMFC, processes in the cell such as transport, reaction and charge processes can be investigated separately. Properties of single layers of the MEA are systematically varied, and subsequent analysis enables identification of the influence of the layer's properties on the electrochemical performance and methanol crossover. Finally, a case study indicates that the use of a membrane with lower methanol diffusivity and a thicker anode micro-porous layer (MPL) yields MEAs with lower methanol crossover but similar power density. 相似文献