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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
J. Jiang Fanghua Mei W. J. Meng G. B. Sinclair Sunggook Park 《Microsystem Technologies》2008,14(6):815-819
For direct imprinting of metals, hard materials such as diamond and SiC have been used to construct mold inserts in preference
to Si, despite the ease in fabricating Si-based micro-/nano- scale structures. In this communication, we demonstrate that
micron scale Al structures can be replicated with good fidelity at room temperature by compression molding with Si inserts
without incurring insert damage. We further report on results of a finite element analysis of the mechanics of the molding
process. The finite element results provide some understanding of the observed lack of damage to the Si inserts. 相似文献
992.
David G.W. Birch 《Information Security Technical Report》2009,14(3):143-145
It is impossible to make any progress on the security vs. privacy debate, or move towards a political settlement around identity for the coming years, unless we develop a more modern notion of what identity is and how it should be addressed online. So long as we maintain an essentially “Victorian” view of the balance between security and privacy, founded on the central concept of identity as a card in a filing cabinet, then society cannot properly take advantage of technological developments. If it does, then security and privacy are no longer competing concerns that need to be balanced but simultaneous deliverables of an infrastructure founded in utility. 相似文献
993.
Ye Chen Keith W. Hipel D. Marc Kilgour Yuming Zhu 《Environmental Modelling & Software》2009,24(5):647-654
Brownfield redevelopment (BR) is an ongoing issue for governments, communities, and consultants around the world. It is also an increasingly popular research topic in several academic fields. Strategic decision support that is now available for BR is surveyed and assessed. Then a dominance-based rough-set approach is developed and used to classify cities facing BR issues according to the level of two characteristics, BR effectiveness and BR future needs. The data for the classification are based on the widely available results of a survey of US cities. The unique features of the method are its reduced requirement for preference information, its ability to handle missing information effectively, and the easily understood linguistic decision rules that it generates, based on a training classification provided by experts. The resulting classification should be a valuable aid to cities and governments as they plan their BR projects and budgets. 相似文献
994.
Task-based abstraction can express user tasks via underlying services with minimal effort. However, developers must first address several issues including task execution transparency, exception handling, ontologies, and abstract architecture design. 相似文献
995.
Alex W. Wardrop 《Networks and Spatial Economics》2009,9(1):123-143
The functions of Australia’s railways are divided between the delivery of suburban passenger railway services, long distance
general and intermodal freight services and regional bulk commodity haulage. There is a national interest in the efficient
carriage of export freight flows because Australia is a major trading nation. Australia’s railways are expected play their
part in hauling export commodities. Unsurprisingly, there are conflicting demands on these railways. Hence, universities,
and the industry itself, are directing research and investigation effort into policy, planning, engineering, operational and
human factors matters. A question which then arises is what means could be used to analyse the problems identified during
this research and investigation. This paper is thus concerned with the inter-relationships between the planning, engineering
and operations of railways in Australia. It identifies four areas of analysis associated with the planning and development
of railway infrastructure and operations. It then discusses a range of analytical tools which could be applied to different
components of these analytical areas and critiques their appropriateness from an Australian perspective. Having made this
assessment, the paper uses a recent Australian case study to show how analytical tools could be used and what lessons might
be learnt from the process.
Figure Use of Railway Analysis Tools from an Australian Perspective
相似文献
Alex W. WardropEmail: |
996.
997.
W B?cher 《Canadian Metallurgical Quarterly》1994,31(6):356-366
The paper deals with the fundamental problem: How does the brain (in the way it is and the way it functions) influence human experience, behaviour and social interaction? Deriving from this question, there's the matter of how all this influences people as road users. After some epistemological considerations the following subjects are dealt with the article: the human perception and human "reality", the limits of human imagination, the basis of human learning, the complexity of processes within the brain, the reaction to changes and the ability to concentrate as well as McLean's theory of the triune brain. The subjects are complemented by aspects of biological and socio-cultural evolution of man, starting from evolutionary ethics going right up to the problem of responsibility. 相似文献
998.
M. J. Annen R. Kizhappali P. W. Carr A. McCormick 《Journal of Materials Science》1994,29(23):6123-6130
Polymerization-induced colloid aggregation is used to synthesize spheres of narrow size distribution which are porous aggregates of ZrO2 colloids. Variation of the reaction pH has been investigated to determine the optimum rate of polymerization of the urea-formaldehyde resin. At the optimum rate, a colloid packing structure is formed where a balance of high porosity and high strength of the aggregates is achieved. This optimum coincides with the maximum yield of the 5 m sintered (polymer-free) particles. Particles synthesized at pH values below the optimum are mechanically weak; some are hollow spheres. Variation of the pore structure, and thus colloid packing structure, is elucidated by nitrogen adsorption and apparent density measurements. Differences on either side of the optimum pH are related to the efficiency of polymer-bridge formation between colloids. 相似文献
999.
We have shown that dicyanogold(I), [Au(CN)(2)](-) is a common metabolite found in blood and urine samples of patients treated with different gold based drugs. Some patients have high levels of gold within their red blood cells (RBCs). Size exclusion and C18 reversed phase chromatography show that the majority of the gold in RBC lysates is bound to protein, but small molecules such as dicyanogold(I) and gold-glutathione complexes are also present. Dicyanogold incubation with red blood cells in vitro leads to a rapid and complete uptake of gold. This uptake is unaffected by DIDS, an inhibitor of the anion channel, but is blocked by the addition of external cyanide. Dicyanogold is also readily taken up by H9 cells, a continuous CD(4+) cell line. This uptake is significantly inhibited by N-ethylmaleimide, suggesting a requirement for sulfhydryl groups. Dicyanogold inhibits the replication of the AIDS virus, HIV, in a cell culture model. 相似文献
1000.