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71.
王晖 《电气电子教学学报》2002,24(6):53-54,60
介绍了英国高校电子专业高等数学教学的基本情况,包括课程内容,教学大纲,考核方式和教材等,分析了它的主要特色,供国内同行参考与借鉴。 相似文献
72.
This paper details developments in the CO2 laser cutting of thick ceramic tiles, that is thicknesses of 8.5 mm and 9.2 mm. These tiles were cut at a combination of different cutting speeds to determine the necessary cutting parameters for various tile geometries. Different cutting modes were used in conjunction with different cutting speeds to investigate cut quality after laser processing. The work also looked into the effects on cutting through using various shield gases. Multipass cutting and underwater cutting were performed to examine their effects on thermal load during processing. 相似文献
73.
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75.
解线性约束凸规划的次最优化方法和改进 总被引:1,自引:0,他引:1
1.引 言 关于线性约束下的非线性规划,很多人进行了研究,Zangwill[3] 于1967年提出了次最优化方法,该方法的原理是将原规划问题化为一系列只含有等式约束的子问题求解,最后找到最优解所在的流形,在此流形上使用无约束规划的各种方法求解原问题即可.薛声家[2]1983 相似文献
76.
Z. J. Huang 《Journal of Optimization Theory and Applications》1992,75(2):331-344
In this paper, by a further investigation of the algorithm structure of the nonlinear block scaled ABS methods, we convert it into an inexact Newton method. Based on this equivalent version, we establish the semilocal convergence theorem of the nonlinear block scaled ABS methods and obtain convergence conditions that mainly depend on the behavior of the mapping at the initial point. This complements the convergence theory of the nonlinear block scaled ABS methods. 相似文献
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78.
Mobile communications suffer from cochannel interference, adjacent channel interference and fading. The cell capacity or the number of users per cell is limited by the interference. In this paper we analyze a new blind adaptive array structure called the spectral correlation discriminator array (SCDA), designed to reject cochannel interference for advanced mobile phone service (AMPS) signals. The blind adaptive array exploits the spectral redundancy in the AMPS signals which arises due to the presence of the supervisory audio tone (SAT). SCDA is shown to provide an improvement of 25–30 dB in signal-to-interference plus noise ratio (SINR) in static multipath channels and 10–15 dB improvement of SINR in Rayleigh fading channels. The SCDA is compared to the least squares constant modulus array (LSCMA) and is shown to have better signal selectivity properties. The reduction in interference power can significantly reduce the frequency reuse factor. 相似文献
79.
Treatment of Red Tide in Ocean Using Non-Thermal Plasma Based Advanced Oxidation Technology* 总被引:6,自引:0,他引:6
Mindong?BaiEmail author Xiyao?Bai Zhitao?Zhang Mindi?Bai Bo?Yang 《Plasma Chemistry and Plasma Processing》2005,25(5):539-550
A Pilot-scale experiment for the treatment of red tide in the enclosure was done in sea area of Shandong Province, P.R. China on Aug. 25, 2002. With the method of micro-gap discharge, O2 in air and H2O in seawater are ionized and dissociated into large numbers of OH• radicals, and then dissolved into a part of seawater to form OH• solution of high concentration. With OH• concentration of 0.68 mg/L, the kill efficiencies of 29 kinds of red tide organisms such as Chaetoceros lorenzianus and so on reached 99.89%, in which bacterium and vibrio were reduced below the detection limit, also Gonyaulax cysts and Prei. Cysts with the crust were done the lowest limit of test. At the same time, the content of chlorophyll-a was decreased below the detection limit. DO (dissolved oxygen) saturation of seawater was greatly increased to 100% because the residual OH• radical was decomposed into H2O and O2 after 20 min. Therefore the treatment of red tide using OH• radicals is a kind of advanced oxidation technology, which realizes zero pollution, zero emission and zero residual in the process of the production of OH• radicals and the treatment of red tide.*Key project of National Foundation Research from Science and Technology Ministry of China, (2002CCC00900); key project of National Natural Science Foundation of China (NSFC; 60031001). 相似文献
80.
This paper is concerned with the solution of nonlinear algebraic systems of equations. For this problem, we suggest new methods, which are combinations of the nonlinear ABS methods and quasi-Newton methods. Extensive numerical experiments compare particular algorithms and show the efficiency of the proposed methods.The authors are grateful to Professors C. G. Broyden and E. Spedicato for many helpful discussions. 相似文献