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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
811.
I. J. Good 《Cryptologia》2013,37(2):65-77
The head of the American contingent at Britain's Government Code and Cypher School (GC&;CS) at Bletchley during World War II tells how he got into cryptology and about his social and administrative experiences as commanding officer of the 6813 th Detachment. 相似文献
812.
Antoine Diguet Maël Le Berre Yong Chen Damien Baigl 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(14):1661-1666
By dragging a phospholipid solution on microstructured silicon surfaces, phospholipid molecules are selectively deposited inside the microstructures to get regular phospholipid multilayer patterns of controlled thickness over a large scale (~cm2). By varying the dragging speed, the thickness of the patterns varies between 28 and 100 nm on average (7 to 25 bilayers). Electroswelling of phospholipid multilayer patterns leads to the formation of giant liposomes of controlled size and narrow size distributions. 相似文献
813.
Understanding the uncertainty of climate models in space and time is necessary to help water resources managers and hydrologists in the selection of appropriate model for a specific application. In this paper, we use three separate methods to evaluate and compare the utility of 14 climate models for seven basins with area range of 2,656–26,355 km2 on the South Korean Peninsula. On the one hand, the method of probabilistic uncertainty analysis is used to evaluate the capability of the studied General Circulation Models (GCMs) in recognizing the extreme events. On the other hand, we use two statistical tests (correlation coefficient and root mean square error) to examine the capability of the GCMs in simulating quantitatively each event. The results show that, for the first method, the performance of climate model varies depending on the number of climate model nodes used for a specific application of given basin, especially for monthly time scale. In addition, we find that, there are several GCMs showing good results for the probabilistic uncertainty test but poor results for the statistical test and conversely. Therefore, climate models should be evaluated for specific applications and specific regions. The results indicated quite clearly that, it is not easy to select an optimal climate model which can satisfy both applications using precipitation and temperature projections. However, the results of this study suggest that, there are several GCMs which are more useful than the others for general hydrological application in South Korean peninsula. 相似文献
814.
汕头超声印制板(二厂)公司藉“节能减排”的契机,打破经验思维的束缚,把汕头超声印制板公司的成果和理念成功运用到本公司的清洁生产工作中,创造了良好的经济效益和环境效益。 相似文献
815.
Clotilde Minfray Thierry Le Mogne Jean-Michel Martin Tasuku Onodera Sayaka Nara Shuko Takahashi 《摩擦学汇刊》2013,56(5):589-601
Zinc phosphate glass is considered to be the main constituent of tribofilms generated under boundary lubrication with zinc dialkyldithiophosphate (ZDDP), a well-known antiwear additive. The reaction occurring during friction between zinc phosphate glasses and steel native iron oxide layer is investigated by both an experimental approach and by Molecular Dynamics simulations (MD). The importance of this “tribochemical” reaction in the general ZDDP antiwear process is discussed. 相似文献
816.
Rare earth organic complexes as down-shifters to improve Si-based solar cell efficiency 总被引:1,自引:0,他引:1
This work reports on the optical and electrical characterization of crystalline silicon based solar modules encapsulated with ethylene-vinyl-acetate layers (that is the encapsulating matrix used nowadays by the photovoltaic industry) doped with a single europium complex whose sensitized region is broadened due to the presence of a co-ligand. Such europium doped EVA layers are able to realize down-shifting of photons with wavelength lower than 460 nm without introducing modifications of the industrial process leading to the fabrication of the photovoltaic modules. This effect has been proven under Air Mass 1.5 conditions (simulating terrestrial applications), where a 2.9% relative increase of the total power delivered by the encapsulated modules has been observed, allowing a reduction in the watt-peak price. 相似文献
817.
818.
This paper deals with a well-known problem in the general area of search theory: optimize the search resources sharing so as to maximize the probability of detection of a (moving) target. However, the problem we consider here considerably differs from the classical one. First, there is a bilevel search planning and we have to consider jointly discrete and continuous optimization problems. To this perspective original methods are proposed within a common framework. Furthermore, this framework is sufficiently general and versatile so as to be easily and successfully extended to the difficult problem of the multizone multisensor search planning for a Markovian target. 相似文献
819.
820.
Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M&R) activities are extremely costly. Unfortunately, the funds available for the M&R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. 相似文献