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71.
Photovoltaics: Quantification of Nano‐ and Mesoscale Phase Separation and Relation to Donor and Acceptor Quantum Efficiency,Jsc, and FF in Polymer:Fullerene Solar Cells (Adv. Mater. 25/2014) 下载免费PDF全文
Wei Ma John R. Tumbleston Long Ye Cheng Wang Jianhui Hou Harald Ade 《Advanced materials (Deerfield Beach, Fla.)》2014,26(25):4399-4399
72.
Waste disposal and waste avoidance are examined from two different perspectives, from the point of view of the waste 'producing' company on the one hand, and from the point of view of the waste disposing company on the other hand. The idea of the basic model lies in the 'turning upside down' of the lot-sizing approach to inventory control theory. We derive a corresponding formula for disposal that shows that the number of waste disposals depends positively on the waste accumulation rate and negatively on the fixed costs for a pick-up. Moreover, we formally work out at which waste avoidance costs a company will enlist the services of a disposal company. Specifically, disposal tends to be preferred to avoidance when waste-avoidance is relatively expensive and three cost rates to be specified are relatively low. Finally, we take the perspective of a monopolistic disposal company that has to decide on the optimal pricing policy. In our model, we determine that the price for a pick-up should be chosen just to cover costs. The disposal company can earn a profit by the suitable choice of the price per unit waste to be disposed of. 相似文献
73.
In current cars, loops are commonly used to redirect the webbing which reels out from the retractor to the passenger's shoulder. Some types of pillar loops, also called D-rings, lead to a non-systematic instability. The webbing, which should scroll without hindrance through the D-ring, laterally shifts, bunches and produces the overturning of the ring. 相似文献
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Marc Blumenau Afrooz Barnoush Ingo Thomas Harald Hofmann Horst Vehoff 《Surface & coatings technology》2011,205(2-3):542-552
The present study discusses the impact of selective oxidation during in-line annealing of Fe–23%Mn–0.6%C–0.3%Si steel on surface and sub-surface properties and is focused on hot-dip galvanizability and susceptibility to hydrogen-induced delayed cracking. Annealing temperature (700–1100 °C) and dewpoint DP (? 15/?30/?50 °C) of the 5%H2–N2 annealing atmosphere were varied in order to investigate Zn wetting in dependence on selective oxidation of Mn and Si. Sub-surface microplasticity (hardness, pop-in frequency, pop-in activation load) was examined by electrochemical nanoindentation in-situ to hydrogen charging (ECNI) to assess hydrogen/material interactions. Zn wetting fails if external Mn and Si oxidation is not avoided by performing high reductive bright annealing (1100 °C/DP ? 50 °C). Zn wetting will however turn to increase if a roughly globular MnO layer appears and Si is internally oxidized (700–900 °C/DP ? 15 °C). Selective oxidation further affects hydrogen/material interactions by influencing the local distribution of solid-soluted Mn: ECNI results indicate hydrogen-induced dislocation demobilization (HEDE mechanism) or dislocation mobilization (HELP mechanism) in dependence on the local amount of solid-soluted Mn within the sub-surface. Macroscopic delayed cracking seems to occur earlier if HELP is predominating. The gained results benefit understanding the impact of selective oxidation on galvanizability and susceptibility to hydrogen-induced failure of austenitic FeMnC steel and advance further developments in processing high Mn alloyed steels. 相似文献
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Dorothea Heiss-Czedik Reinhold Huber-Mörk Daniel Soukup Harald Penz Beatriz López García 《Journal of Visual Communication and Image Representation》2009,20(6):389-398
Most color image sensors use color filter arrays (CFA). With this sensor design the captured information at each sensor pixel position is restricted to a specific spectral portion (typically red, green and blue bands). To obtain the missing color responses at each pixel position, so-called CFA demosaicing algorithms are commonly used. We propose two new CFA demosaicing algorithms, which are well suited for industrial print inspection with respect to the requirements in accuracy and speed. As a main contribution, we introduce novel demosaicing algorithms for specific high-speed color digital time delay and integration (DTDI) CFA line-scan cameras. We compare the suggested CFA demosaicing algorithms to state-of-the art algorithms for area and line-scan camera operation modes. We show that the two new algorithms perform superior to conventional algorithms as indicated by reconstruction error. 相似文献
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Harald Reiss 《Journal of Superconductivity and Novel Magnetism》2013,26(3):593-617
The ratio J Crit[T(x,y,t)]/J Crit[T(x,y,t 0)] of critical current densities (t 0 indicating start of a disturbance) integrated over sample cross section serves to calculate the “stability function”, Φ(t), to predict under which conditions zero-loss transport current is possible. Critical current density and stability function are correlated with (conventional) timescale, t, in the superconductor (the “phonon aspect”). However, the stability problem is not simply restricted to coupled conduction/radiation heat transfer. It is questionable whether decay of electron pairs and subsequent recombination of excited electron states to a new dynamic equilibrium (the “electron aspect” under a disturbance) proceeds on the same timescale. A sequential model has been defined to calculate lifetimes of the excited electron states. These are estimated from analogy to the nucleon–nucleon, pion-mediated Yukawa interaction, from an aspect of the Racah-problem (expansion of an antisymmetric N-particle wave function from a N?1 parent state) and from the uncertainty principle, all in dependence of the local (transient) temperature field; with these approximations, the sequential model accounts for the retarded electron–phonon interaction. The numerical analysis is applied to NbTi and YBaCuO filaments in a standard matrix. As a result, the difference between both timescales can be significant, in particular near the phase transition: in the NbTi filament, a minimum distance of at least 60 μm (in this example) from the location of a disturbance should be observed for reliable stability analysis. This difference could have consequences also for safe operation of a resistive fault current limiter. 相似文献