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991.
One or more layers of textiles can provide a thermal resistance between the human body and its environment, and so help maintain the body in a thermally comfortable state. The effect of wind on and its penetration through such thermal cladding is examined experimentally.  相似文献   
992.
The newly developed ingot growing techniques, as the three-grain and the columnar multigrain ingot processes, are now offering the possibility of slicing thinner wafers (≤ 100 μm). In this paper we present the results obtained on p type large area (≥ 100 cm2) and 100 μm thick wafers by using both conventional and reverse cell manufacturing technologies.The conventional cells are provided with aluminium or boron BSF plus screen-printed silver mirror or a silver-aluminium net; the reverse cells have a FSF and the deep back junction completely covered by a screen-printed or CVD silver layer.The constructing parameters have been chosen on the base of one and two dimensions modeling and both raw material and devices have been completely characterized.This work shows that very thin wafers do not introduce serious problems for the conventional manufacturing of solar cells. The efficiencies of the normal and of the reverse cells are found to be comparable and are of the same order than those of thicker cells, however at a significant lower cost. The main obtained result has to be related to the demonstration of a cell manufacturing feasibility starting from very thin wafers.  相似文献   
993.
Markets and Hierarchies and (Mathematical) Economic Theory   总被引:4,自引:0,他引:4  
Over the past decade transaction-cost economics has been partiallytranslated in the more mathematical language of game theory,and understanding of the costs of transactions has been deepened,refined and extended. But the translation is incomplete: a greatdeal of human behaviour is missed, and doing game theory withmore life-like models of individuals will bring theory closerto phenomena. Transaction-cost economics, particulary the economicsof relational contracts, provides a major arena for these developments,since the important issues of bounded rationality and individualbehavior are central to the topic.  相似文献   
994.
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996.
We obtain expressions for biased estimates for parameters of binomial distributions with allowance fora priori information; our starting poins is the Rao-Kramer inequality. Translated from Izmeritel'naya Tekhnika, No. 10, pp. 14–16, October, 1996.  相似文献   
997.
The author studies dynamic scheduling of computational tasks with communication costs using nonuniform memory access architecture. The computing model assumes that data transfer can be partitioned into parallel and sequential parts with respect to the task execution. A scheduling heuristic, called least-communication (LC), together with a two-level scheduler is proposed in an attempt to minimize the finish time. The LC selects the task that removes the largest amount of remaining data transfer, if no such tasks are available the task that has been ready to run at the earliest is selected first. The time complexity of LC is O(n2). Testing the finish time of LC and first-come first-served scheduling (FCFS) shows that LC is useful for tasks having moderate granularity and whose computation and communication requirements vary widely for different data sets  相似文献   
998.
999.
The ACTS program is moving the results of the R&D of the parent RACE program nearer to realization through technology and user trials. Particularly in the mobile domain of ACTS, several projects have been investigating the user dimension in the context of the third-generation Universal Mobile Telecommunications Service. Results so far suggest many opportunities to broaden participation, exploit the inherent benefits of the mobile environment, and take advantage of the enormous improvements in wireless communications to realize the potential of global multimedia mobility. This article considers the needs of users for mobile multimedia applications and the consequences of those needs on the equipment, supporting services and teleservices, and communications bearers  相似文献   
1000.
In the motion control field, a disturbance observer-based disturbance canceling control is often used as a robust control methodology. However, this method is nothing more than an alternative design of an integral controller, and the robust stability issue cannot be directly accounted for. In this paper, an extended H control scheme is proposed as a new robust motion control method which achieves the disturbance cancellation ability and guarantees robust stability automatically  相似文献   
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