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排序方式: 共有1623条查询结果,搜索用时 15 毫秒
141.
Armin Herb 《Datenschutz und Datensicherheit - DuD》2011,35(4):270-274
Die Finanzierung des dualen Rundfunksystems in Deutschland und damit insbesondere der ?ffentlich-rechtlichen Rundfunkanstalten
soll ab dem 1. Januar 2013 auf eine neue Basis gestellt werden. Anstatt den bisherigen Gebühren für ein H?rfunk- oder Fernsehger?t
ist dann ein Rundfunkbeitrag für jede Wohnung und Betriebsst?tte zu leisten. Die nachfolgenden Ausführungen befassen sich
mit den datenschutzrechtlichen Vorschriften im neuen Rundfunkbeitragsstaatsvertrag der L?nder. 相似文献
142.
R. D. Moser P. G. Allison M. Q. Chandler 《Journal of Materials Engineering and Performance》2013,22(12):3902-3908
Little work has been done to study the fundamental material behaviors and failure mechanisms of cement-based materials including ordinary Portland cement concrete and ultra-high performance concretes (UHPCs) under high strain impact and penetration loads at lower length scales. These high strain rate loadings have many possible effects on UHPCs at the microscale and nanoscale, including alterations in the hydration state and bonding present in phases such as calcium silicate hydrate, in addition to fracture and debonding. In this work, the possible chemical and physical changes in UHPCs subjected to high strain rate impact and penetration loads were investigated using a novel technique wherein nanoindentation measurements were spatially correlated with images using scanning electron microscopy and chemical composition using energy dispersive x-ray microanalysis. Results indicate that impact degrades both the elastic modulus and indentation hardness of UHPCs, and in particular hydrated phases, with damage likely occurring due to microfracturing and debonding. 相似文献
143.
We present a mean-field approach for calculating thermodynamic properties(free energies) of protein–solvent systems. We apply this method to thetumor suppressor protein p53, where we study the stability of itstetramerization domain when subjected to site-directed mutagenesis. Acomparison with experimental results is included. 相似文献
144.
145.
Analytic models based on discrete-time Markov chains (DTMC) are proposed to assess the algorithmic performance of Software Transactional Memory (TM) systems. Base STM variants are compared: optimistic STM with inplace memory updates and write buffering and pessimistic STM. Starting from an absorbing DTMC, closed-form analytic expressions are developed, which are quickly solved iteratively to determine key parameters of the considered STM systems, like the mean number of transaction restarts and the mean transaction length. Since the models reflect complex transactional behavior in terms of read/write locking, data consistency checks and conflict management independent of implementation details, they highlight the algorithmic performance advantages of one system over the other, which – due to their at times small differences – are often blurred by implementation of STM systems and even difficult to discern with statistically significant discrete-event simulations. 相似文献
146.
RC MacPhail HA Tilson VC Moser GC Becking V Cuomo E Frantík BM Kulig G Winneke 《Canadian Metallurgical Quarterly》1997,18(4):925-928
Numerous events over several years culminated in recognition of the need to explicitly evaluate the nervous system as a potential target for environmental chemicals. Based on recommendations from several international expert panels, the International Programme on Chemical Safety (IPCS) sponsored the Collaborative Study on Neurobehavioral Screening Methods. A Steering Committee was created to oversee the project, develop the testing protocol, recruit participating laboratories and review and analyze the data. The protocol specified the tests, the chemicals (supplied from a common source) and the exposure conditions (acute and repeated dosing). Test methods were based upon existing practices in toxicological screening as well as recent advances in neurotoxicity screening. Chemicals were selected to produce different profiles of neurobehavioral effects. Considerable latitude was afforded the participating laboratories in the choice of several key variables (e.g., strain of rat, testing device for motor activity assessment) that could potentially affect the results of the experiments. The approach therefore provided a standardized yet flexible protocol for evaluating the reproducibility of neurobehavioral screening data in diverse laboratory settings. 相似文献
147.
148.
Christine Bratrich Bernhard Truffer Klaus Jorde Jochen Markard Werner Meier Armin Peter Matthias Schneider Bernhard Wehrli 《河流研究与利用》2004,20(7):865-882
Hydropower is the most important renewable electricity source worldwide. It shows clear advantages for the global CO2 balance but creates serious ecological impacts on a local scale. As a consequence, concern for the conservation of natural river ecosystems is growing within society and more people are willing to pay extra for so‐called ‘green electricity’. The definition of ‘green’, however, is not straightforward and customers cannot directly examine the quality of electricity products. Therefore, credible certification of high ecological standards is essential for successful green electricity marketing. In this paper we introduce a new assessment procedure for evaluating environmentally compatible hydropower production. This so‐called ‘Green Hydro’ concept was developed in the context of a multidisciplinary case study on a 400 MW hydropower scheme in the Southern Alps of Switzerland. The concept guarantees both general standards for different schemes operating in different types of watersheds and flexibility for local particularities. We developed an environmental management matrix that considers basic criteria and eco‐investments and covers five environmental areas of concern (i.e. hydrological character, connectivity, morphology, landscape, and biological communities). The ecological perspective is complemented by five management domains (i.e. instream flow regimes, hydropeaking, reservoir and bedload management, and power plant structures). Applying assessment and modelling tools for the Green Hydro procedure showed that dynamic habitat models allowed quantification of the effects of different instream flow regulations at morphologically distinct sites. In this case, morphological restoration could be more beneficial than increasing the minimum flow. The first experience with the Green Hydro certification is encouraging. So far, 13 facilities have successfully passed the certification procedure. They produce a total of 186 GWh green electricity per year, which is sufficient for the supply of almost 40 000 households in Switzerland. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
149.
Armin De Meijere Klaus Michelsen Rolf Gleiter Jens Spanget-Larsen 《Israel journal of chemistry》1989,29(2-3):153-164
The syntheses of the new hydrocarbons trimethylenetriasterane 12 , trispirocyclopropanetriasterane 3 , trispirocyclopropanenortricyclane 4 , and of the trispirocyclopropanenorbornanes 5, 6 , and 7 are reported. 12 contains six vinylcyclopropane units rigidly held in an antiperiplanar (ap) conformation in a D3h symmetric framework. 3 and 4 are the first model compounds with bicyclopropyl units rigidly fixed in an s-trans (ap) conformation (Θ = 180°). Their PE spectra reveal that the interaction parameter βww = −1.73 eV for this arrangement is the same as that for Θ = 0°. 相似文献
150.
The maximum bubble-pressure method has been used to measure the surface tension and density of liquid alloys (Ag-Sn)eut + Cu (XCu = 0.005, 0.020, 0.0375, and 0.065 (mole fraction)). The surface tension and density measurements were curried out in the
temperature ranges of 262–942°C and 264–937°C, respectively. The linear dependencies of surface tensions and densities on
temperature were observed, and they were described by straight-line equations. It has been found that the additions of Cu
to the Ag-Sn eutectic alloy increase the surface tension. Experimental data of the surface tension were compared with those
from modeling based on Butler’s method, using the optimized-thermodynamic parameters from the literature, and a slight tendency
contrary to the experimental results was observed. 相似文献