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991.
992.
The microwave propagation-dominated problem in the multilayer structure made of a BCS superconducting film and a dielectric substrate is investigated theoretically by using the modified two-fluid model and transmission line theory. The effective microwave surface impedances are studied as functions of temperature, frequency, and film thickness, as well as substrate thickness. Special attention is paid to the substrate resonance phenomenon in the resonant structure. The influence of BCS coherence effects on surface impedance and resonant behavior is clearly demonstrated. The resonant effect in the stack structure is well interpreted with the help of the transverse resonance technique in the microwave theory 相似文献
993.
本文根据实地考察内容,结合宽带网络技术和业务重点及实施策略,全面介绍了日本关西宽带实验网发展背景,通信与广播电视综合应用实验和B-ISDN实用化实验的进展以及NTT所起作用。文章最后就关西宽带实验网的借鉴意义提出了几方面意见。 相似文献
994.
The effects of H2O and NH3 on the kinetics of the liquid phase hydrogenation of tetralin to decalin at 6.9 MPa and 330°C over commercial P---Ni---Mo/alumina catalysts in the presence of H2S have been investigated. H2O functioned as a mild kinetic inhibitor to an extent sensitive to the H2S level. Quasi in situ XPS was used to investigate the catalyst structure after exposure to H20/H2S. 相似文献
995.
在管理信息系统的开发以及分布式数据库系统的设计中,已开始使用面向对象的技术.本文论述了面向对象的设计特征,介绍了用于面向对象设计的各种实现语言,并着重分析了各种实现语言支特面向对象设计的能力. 相似文献
996.
Montserrat Bóo Francisco Argüello Javier D. Bruguera Emilio L. Zapata 《The Journal of VLSI Signal Processing》1997,17(1):57-73
A rate 1/n binary generic convolutional encoder is a shift-register circuit where the inputs are information bits and the outputs are blocks of n bits generated as linear combinations on the appropriate shift register contents. The decoding of the outputs of a convolutional encoder can be carried out by the well-known Viterbi algorithm. The communication pattern of the Viterbi Algorithm is given as a graph, called trellis, associated to the state diagram of the corresponding encoder. In this paper we present a methodology that permits the efficient mapping of the Viterbi algorithm onto a column of an arbitrary number of processors. This is done through the representation of the data flow by using mathematical operators which present an inmediate hardware projection. A single operator string has been obtained to represent a generic encoder through the study of the data flow of free-forward encoders and feed-back encoders. The formal model developed is employed for the partitioning of the computations among an arbitrary number of processors in such a way that the data are recirculated opimizing the use of the processors and the communications. As a result, we obtain a highly regular and modular architecture suitable for VLSI implementation. 相似文献
997.
998.
详细研究了以乙酸乙酯和环己烷为溶剂,丙烯酸为单体,BPO,LPO,AIBN为引发剂,聚烯基多醚为交联剂,合成增稠能力强、透明度高的聚丙烯酸树脂。于混和溶剂存在下制得的聚合物,消除了以往由二氯甲烷为溶剂的反应介质中所得产品的毒性,可广泛应用于医药及日用化工等行业。 相似文献
999.
In arc welding processes, because of the complexity and nonlinearity of heat transfer phenomena, it is often difficult to design an effective control system based upon an exact mathematical model. In this paper, a self-organizing fuzzy control method is proposed to obtain a uniform weld quality by regulation of the surface temperature at a desired level. The proposed control system is designed to comprise a combined structure of the fuzzy SOC with conventional PD control for improving the system's stability. The control experiments show that the proposed controller guarantees a uniform weld quality for various welding conditions. 相似文献
1000.
Since the late 1980s, the eight-component model of the comprehensive school health program (CSHP), has been adopted widely in the United States and internationally. While it is acknowledged that the eight program elements should be delivered in a coordinated, interactive manner, numerous issues regarding how this integration best can be achieved, including who at the school level should have this responsibility and how the eight components relate conceptually and logistically, have not been addressed adequately. In essence, a CSHP transforms several solo performers into an orchestra. This article proposes the school health coordinator as an essential element in the eight-component model of the CSHP--the maestro, without whom there can be no symphony. The coordinator's principal responsibilities include administration, integration of personnel and programs, evaluation, and direct intervention. Three program elements--staff wellness, healthy environment, and community/family involvement--are subsumed within the coordinator's role, effectively reducing the number of program elements from eight to five. Potential benefits in addition to issues regarding feasibility of the SHC, are discussed and studies examining the effectiveness of the SHC model are recommended. 相似文献