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991.
We present an all-aluminum MEMS process (Al-MEMS) for the fabrication of large-gap electrostatic actuators with process steps that are compatible with the future use of underlying, pre-fabricated CMOS control circuitry. The process is purely additive above the substrate as opposed to processes that depend on etching pits into the silicon, and thereby permits a high degree of design freedom. Multilayer aluminum metallization is used with organic sacrificial layers to build up the actuator structures. Oxygen-based dry etching is used to remove the sacrificial layers. While this approach has been previously used by other investigators to fabricate optical modulators and displays, the specific process presented herein has been optimized for driving mechanical actuators with relatively large travels. The process is also intended to provide flexibility for design and future enhancements. For example, the gap height between the actuator and the underlying electrode(s) can be set using an adjustable polyimide sacrificial layer and aluminum “post” deposition step. Several Al-MEMS electrostatic structures designed for use as mechanical actuators are presented as well as some measured actuation characteristics  相似文献   
992.
What is the implication for business when information technology (IT) changes in the workplace without a commensurate change in the composition of business programs educating tomorrow's employees? A survey of MBA graduates forms the basis of this article on the IT skills needed in the marketplace.  相似文献   
993.
Conclusions The generalized Chebyshev inequalities are of independent value in mathematical analysis, probability theory, and other fields. Survivability analysis of elements and systems requires specification of functional probability characteristics-distributions of the current durability point. Probabilistic calculation of survivability of complex systems can be carried out using logical-probabilistic methods [22, 28], because the probabilistic-physical meaning of the distribution of current durability point at the point x is the failure probability of an element (a system) given the deterministic level x of the next shock. The methodology of reliability theory can be updated by focusing on a physical stochastic process, instead of time to failure, as the cause of failure. In conclusion, I would like to thank I. A. Ibragimov for discussion of results and some useful comments. Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 159–166, March–April, 1994.  相似文献   
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997.
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 172–176, May–June, 1994  相似文献   
998.
This research was supported under project No. 6.02.02/128-93 as part of the state scientific-technical program on future information technologies and systems by the Ukrainian State Committee, of Science and Technology.  相似文献   
999.
The presence of dissimilar network models and standards necessitates interoperability as a means of achieving ubiquitous connectivity and management. The primary focus of this paper is to identify interoperability issues, independent of the network management model, which form the basis for developing interworking paradigms. Network Management and Interoperability related concepts and terminology are introduced and a generic network management framework is presented. Based on the generic framework, interoperability issues for developing paradigms are identified systematically. Different paradigms for interoperability are described and compared. The techniques used by these paradigms in addressing the issues identified are discussed.  相似文献   
1000.
The aditi deductive database system   总被引:2,自引:0,他引:2  
Deductive databases generalize relational databases by providing support for recursive views and non-atomic data. Aditi is a deductive system based on the client-server model; it is inherently multi-user and capable of exploiting parallelism on shared-memory multiprocessors. The back-end uses relational technology for efficiency in the management of disk-based data and uses optimization algorithms especially developed for the bottom-up evaluation of logical queries involving recursion. The front-end interacts with the user in a logical language that has more expressive power than relational query languages. We present the structure of Aditi, discuss its components in some detail, and present performance figures.  相似文献   
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