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981.
叶巧云 《平顶山工学院学报》2000,9(1):34-36
针对GPS测量实际工作中 ,影响GPS测量的成果质量和工效的因素进行了分析研究 ,并提出了解决的办法。对完善GPS测量的技术和方法 ,具有一定的指导意义。 相似文献
982.
This paper presents a hybrid efficient genetic algorithm (EGA) for the stochastic competitive Hopfield (SCH) neural network, which is named SCH–EGA. This approach aims to tackle the frequency assignment problem (FAP). The objective of the FAP in satellite communication system is to minimize the co-channel interference between satellite communication systems by rearranging the frequency assignment so that they can accommodate increasing demands. Our hybrid algorithm involves a stochastic competitive Hopfield neural network (SCHNN) which manages the problem constraints, when a genetic algorithm searches for high quality solutions with the minimum possible cost. Our hybrid algorithm, reflecting a special type of algorithm hybrid thought, owns good adaptability which cannot only deal with the FAP, but also cope with other problems including the clustering, classification, and the maximum clique problem, etc. In this paper, we first propose five optimal strategies to build an efficient genetic algorithm. Then we explore three hybridizations between SCHNN and EGA to discover the best hybrid algorithm. We believe that the comparison can also be helpful for hybridizations between neural networks and other evolutionary algorithms such as the particle swarm optimization algorithm, the artificial bee colony algorithm, etc. In the experiments, our hybrid algorithm obtains better or comparable performance than other algorithms on 5 benchmark problems and 12 large problems randomly generated. Finally, we show that our hybrid algorithm can obtain good results with a small size population. 相似文献
983.
莱钢集团全面风险管理信息系统实现了风险收集、风险归档、风险事件库、风险评估、风险图谱、风险文化管理和系统管理功能.实现全员、全面、全方位、全过程的风险管理,使公司生产经营管理风险得到有效控制. 相似文献
984.
低渗透油藏有效厚度下限标准研究 总被引:5,自引:0,他引:5
低渗透油藏储层物性较差,通常油层在酸化压裂等工艺技术措施下,才可产出工业油流,对低渗透油藏有效储层进行测井解释较为困难。从冷家堡油田冷46区块的油藏特征出发,建立了一套有效厚度下限标准研究方法。为检测油层有效厚度划分精度,在取心井中选取5口井进行岩心厚度与测井厚度对比,层划准率达100%。并据此标准划分39口单井有效厚度,有效地保证油层射孔,为注水开发提供可靠的依据。 相似文献
985.
The paper presents experimental results of evaluation of the data transfer speed between a mobile object and base stations of a wireless 802.11.g standard network. Estimates are produced for different velocities of object motion. At the same time, measurement was carried out on the signal-to-noise ratio in a channel. A functional relation has been established between the real data transfer speed and the signal-to-noise ratio in the channel of the wireless net connected to a mobile object. 相似文献
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Don E. Smith 《Computers & Industrial Engineering》1986,11(1-4):124-127
The primary purpose of this paper is to present a computerized lease-versus-buy program utilized by the Defense Contract Audit Agency to monitor defense contractor data processing hardware procurement. The main points of the paper shall pertain to the financial elements incorporated into the software, reports generated, and the resulting lease-versus-buy decision. Discussion of the lease-versus-buy process shall relate primarily to the procurement of data processing equipment. The approach taken in the lease-versus-buy decision process for procuring data processing equipment is basically no different from the methodology used in acquiring other types of capital equipment. Hence, the proposed microcomputer-based program used to performed lease-versus-buy analysis for data processing equipment is suitable for industrial equipment procurement, as well. 相似文献
990.
Aimo A. Trn 《Decision Support Systems》1990,6(4)
The working of a tool, Simulation Nets, for designing and executing models for simulation of systems is presented. The tool is an extension of the theoretically attractive Petri Nets, whose suitability in general simulation modeling has largely been overlooked in the simulation community. Simulation Nets helps in obtaining a correct simulation model because of their good graphical properties, their strength in describing concurrent processes, and because of the possibility in proving correctness for some parts of the model by applying the well known reachability tree technique. The resulting graphical model consists of a number of submodels. The submodels are exact enough to permit simulation experiments to be performed without the need of programming. This permits easy incremental validation of the model, i.e., validation of the submodels and a hierarchy of coupled submodels. Simulation nets thus facilitates rapid modeling and experimentation and thus supports the decision maker in obtaining the data needed for him to make his decision. Experiences with a working prototype are presented. 相似文献