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Hobert  Anne  Jahn  Najko  Mayr  Philipp  Schmidt  Birgit  Taubert  Niels 《Scientometrics》2021,126(12):9751-9777

This study investigates the development of open access (OA) to journal articles from authors affiliated with German universities and non-university research institutions in the period 2010–2018. Beyond determining the overall share of openly available articles, a systematic classification of distinct categories of OA publishing allowed us to identify different patterns of adoption of OA. Taking into account the particularities of the German research landscape, variations in terms of productivity, OA uptake and approaches to OA are examined at the meso-level and possible explanations are discussed. The development of the OA uptake is analysed for the different research sectors in Germany (universities, non-university research institutes of the Helmholtz Association, Fraunhofer Society, Max Planck Society, Leibniz Association, and government research agencies). Combining several data sources (incl. Web of Science, Unpaywall, an authority file of standardised German affiliation information, the ISSN-Gold-OA 3.0 list, and OpenDOAR), the study confirms the growth of the OA share mirroring the international trend reported in related studies. We found that 45% of all considered articles during the observed period were openly available at the time of analysis. Our findings show that subject-specific repositories are the most prevalent type of OA. However, the percentages for publication in fully OA journals and OA via institutional repositories show similarly steep increases. Enabling data-driven decision-making regarding the implementation of OA in Germany at the institutional level, the results of this study furthermore can serve as a baseline to assess the impact recent transformative agreements with major publishers will likely have on scholarly communication.

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The paper describes an analysis of standardized and non-standardized test methods for polymeric insulating materials, either suitable or applied for, outdoor HV insulation. The analysis particularly considers the increasing use of silicone elastomers for composite insulators. In the first part, test methods covering erosion/tracking performance and hydrolysis phenomena are discussed. These are inclined plane test (IPT) and arc test (AT) for the evaluation of the tracking and erosion behavior as well as boiling water test (BWT) for the evaluation of the HV diffusion-breakdown-strength. These tests have a long tradition in the field of material research. Secondly, the resistance of hydrophobicity under accelerating aging conditions using simultaneous moisture and voltage stress is considered. Results from the rotating wheel dip test (RWDT) are presented and related to results from an equivalent salt-fog test. The third part of the paper deals with the regeneration of hydrophobicity after sample exposure to moisture and corona discharges. Recovery includes also the transfer of hydrophobicity into pollution layers, which is quantified by measurement of dynamic contact angle  相似文献   
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For the design of satellite links, detailed knowledge of the transmission characteristics is important. Development issues such as channel measurements, feasibility and performance studies, pre-operational demonstration and verification tests, etc., are necessary or desirable before launch. For this task, another satellite might and should eventually be used. However, if a suitable test satellite is not available and if a tower, mountain, or cliff is not feasible, a proper airborne platform is necessary to emulate the characteristics of the satellite under investigation as closely as possible. This situation is assumed in the following. In this paper, theoretical as well as practical arguments are derived and collected, respectively: (i) to guide the selection of a suitable platform; (ii) to predict its limitations; and (iii) to consider the time-variant behaviour of satellite orbiting. The capabilities of a helicopter platform and of an airplane platform are demonstrated, supported by data recently collected in several test campaigns. © 1997 by John Wiley & Sons, Ltd.  相似文献   
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The mechanical behavior and microstructure evolution during deformation of novel austenitic Cr–Mn–Ni as‐cast steels with varied Ni content were investigated at various temperatures using static tensile tests, optical microscopy, and the magnetic scale for the detection of ferromagnetic phase fraction. To summarize all knowledge about the deformation‐induced processes, the STT and DTT diagrams were developed for Cr–Mn–Ni steels. The diagrams illustrate the different deformation mechanisms depending on temperature and tension load, and quantify the elongation of the deformation mechanisms. The deformation‐induced ε‐ and α' martensite formation and twinning – the TRIP and TWIP effects – occur in the Cr–Mn–Ni steels depending on the chemical composition and temperature. The differences of deformation‐induced processes depend on thermodynamics and are confirmed by thermodynamic calculations. The nucleation threshold of γ → α′ transformation was determined for the investigated Cr–Mn–Ni steels.  相似文献   
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In this paper, we report a methodology, developed in the context of Smart Energy Efficient Middleware for Public Spaces European Project, aimed at exploiting ICT monitoring and control services to reduce energy usage and CO2 footprint in existing buildings. The approach does not require significant construction work as it is based on commercial-off-the-shelf devices and, where present, it exploits and integrates existing building management systems with new sensors and actuator networks. To make this possible, the proposed approach leverages upon the following main contributions: (a) to develop an integrated building automation and control system, (b) to implement a middleware for the energy-efficient buildings domain, (c) to provide a multi-dimensional building information modelling-based visualisation, and (d) to raise people’s awareness about energy efficiency. The research approach adopted in the project started with the selection, as case studies, of representative test and reference rooms in modern and historical buildings chosen for having different requirements and constraints in term of sensing and control technologies. Then, according to the features of the selected rooms, the strategies to reduce the energy consumptions were defined, taking into account the potential savings related to lighting, heating, ventilation, and air conditioning (HVAC) systems and other device loads (PC, printers, etc.). The strategies include both the control of building services and devices and the monitoring of environmental conditions and energy consumption. In the paper, the energy savings estimated through simulation, for both HVAC and lighting, are presented to highlight the potential of the designed system. After the implementation of the system in the demonstrator, results will be compared with the monitored data.  相似文献   
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