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81.
82.
提出并讨论了两种实现码分多址系统中最佳多用户检测的神经网络方法。一种基于离散Hopfield神经网络,另一种基于采用反向传播算法的多层感知器神经网络。理论分析和计算机模拟都证实了这两种神经网络方法的可行性,优越性和实用性。前者适用“固定”用户情况;后者既可用于“固定”用户吼适用于移动用户的情况,因而在未来的CDMA个人通信网中有较好的应用前景。 相似文献
83.
Ye. L. Stolov 《Journal of Electronic Testing》1993,4(3):283-283
Let a circuit havem outputs,m>1. There are two ways to test this circuit by means of a signature analyzer: use a single input analyzer for each output or use anm-input analyzer to test all outputs simultaneously. The main goal of this letter is to demonstrate that for fault output sequences with small multiplicity of errors and long length the second approach is more effective. 相似文献
84.
The aim of this paper is to assess the state-of-the-art in the Decision Support Systems (DSS) field from both a research and a practice perspective. Three main dimensions of DSS research and practice are addressed: 1) supporting human decision-making processes, 2) integrating DSS into the organizational context, and 3) identifying new application domains. The related analysis and discussion provides a better understanding of past developments in the DSS field and insights into future evolution patterns. 相似文献
85.
钢中非金属夹杂物显微评级方法的定量化探讨 总被引:2,自引:0,他引:2
应用IBAS系列图像分析系统,对建立一套与国家标准GB10561─89兼容的钢中非金属夹杂物显微评级方法的自动化和定量化标准作了可行性分析,结果表明建立这套标准是切实可行的。 相似文献
86.
球罐活性缺陷的模糊评定方法 总被引:6,自引:0,他引:6
根据国内外有关标准和文献,利用模糊数学中的模糊描述和隶属度等概念,首次采用多级模糊综合评定理论,分层次地把活性缺陷的主要监测信息(即声发射源信息)和专家们的经验考虑在内,建立在用球形贮罐声发射源严重度多级模糊综合评定模型和方法,并编制计算机数据分析和处理程序,使评定结果趋于更合理和可靠.并给出在用球形贮罐声发射源严重度多级模糊综合评定算例,结果表明,该评定方法可以达到定量化的程度,与局部无损复验结果有良好的一致性. 相似文献
87.
Abstract. This paper examines the capacity of the research designs of 37 empirical studies of information systems (IS) effectiveness to provide a basis for the development of theories about behaviour related to IS effectiveness. The power of each study to support causal inference was evaluated in terms of (a) its handling of the time dimension, (b) its ability to weigh differences and (c) its resistance to internal validity threats that pose alternative explanations for its reported findings. Of the reviewed studies, 29.7% could account for the time dimension, 32.4% employed a comparison group and 16.2% were not susceptible to any internal validity threats. Only 13.5% of the studies combined an accounting for the time dimension with the use of a comparison group. Of these, however, only 5.4% were also invulnerable to internal validity threats. The research designs of nearly 95% of these published studies were deficient in supporting causal inference. In those studies, suggestions that one variable was causally related to another variable could not be substantiated. Encouragement for the future capacity of IS effectiveness research to support causal inference was found in a trend towards the use of quasiexperimental designs. Recommendations are made regarding ways to increase the inferential capacity of research designs employed in the study of IS effectiveness. 相似文献
88.
本文介绍了大坝施工混凝土质量的评价系统软件的设计思路和设计成果。它利用现代计算机技术和应用模糊数学理论评价混凝土重力坝和拱坝单块和整体的质量。在采用模糊综合评价工程质量中,对不同工艺环节,对坝体不同部位,鉴于其质量要求的差异应赋予不同的权重,在权重的取值上采用了专家调查排序,定量转化的方法是比较适宜的。在程序设计中,评价数学模型采用了BASIC程序,访膜块通过*TXT文件实现了与整个大坝混凝土质量微机管理系统的接口及数据传递。操作运行方便灵活。 相似文献
89.
In a survey of the practical wind energy resource present in the Tayside Region of Scotland it was estimated that over 1500 km2 of land is suitable for wind energy development in the Region after consideration of a range of physical, technical and institutional factors. Wind speed data for this survey was obtained from the Energy Technology Support Unit (ETSU) UK Wind Speed Data Package. To verify the wind speeds obtained from the ETSU package a representative sample of sites in and around the identified areas of potential in Tayside were modelled for mean annual wind speed using the Wind Atlas Analysis and Application Program (WAsP). The wind speeds for the sites obtained from the WAsP analysis were compared with those obtained from the ETSU UK Wind Speed Data Package and conclusions drawn as to the reliability of the Tayside wind energy survey and the general applicability of the ETSU package for broad wind energy resource assessment. 相似文献
90.
The analysis of recently collected wind data at five sites in Saudi Arabia namely, Dhulum, Arar, Yanbu, Gassim and Dhahran is presented. The five sites represent different geographically and climatologically conditions. The data collected over a period spanned between 1995 and 2002 with different collection periods for each site. Daily, monthly and frequency profiles of the wind speed at the sites showed that Dhulum and Arar sites have higher wind energy potential with annual wind speed average of 5.7 and 5.4 m/s and speeds higher than 5 m/s for 60 and 47% of the time, respectively. The two sites are candidates for remote area wind energy applications. The costal site's, i.e. Yanbu and Dhahran wind speed data indicated that the two sites have lower annual wind speed averages and wind blows at speed higher than 5 m/s during afternoon hours. That makes the two sites candidates for grid connected wind systems for electrical load peak shaving. The data of Gassim site showed that the site has the lowest wind energy potential compared to the others. The annual energy produced by a Nordex N43 wind machine is estimated to be 1080, 990, 730, 454 and 833 MWh for Dhulum, Arar, Yanbu, Gassim and Dhahran, respectively. The analysis showed that the estimated annual energy produced by the machine based on 10 min averaged data is 2.5% higher than the estimated energy based on 30 min averaged data. 相似文献