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71.
Erica L. Plambeck Bor-Ruey Fu Stephen M. Robinson Rajan Suri 《Mathematical Programming》1996,75(2):137-176
In this paper we propose a method for optimizing convex performance functions in stochastic systems. These functions can include
expected performance in static systems and steady-state performance in discrete-event dynamic systems; they may be nonsmooth.
The method is closely related to retrospective simulation optimization; it appears to overcome some limitations of stochastic
approximation, which is often applied to such problems. We explain the method and give computational results for two classes
of problems: tandem production lines with up to 50 machines, and stochastic PERT (Program Evaluation and Review Technique)
problems with up to 70 nodes and 110 arcs.
Sponsored by the National Science Foundation under grant number CCR-9109345, by the Air Force Systems Command, USAF, under
grant numbers F49620-93-1-0068 and F49620-95-1-0222, by the U.S. Army Research Office under grant number DAAL03-92-G-0408,
and by the U.S. Army Space and Strategic Defense Command under contract number DASG60-91-C-0144. The U.S. Government has certain
rights in this material, and is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding
any copyright notation thereon.
Sponsored by a Wisconsin/Hilldale Research Award, by the U.S. Army Space and Strategic Defense Command under contract number
DASG60-91-C-0144, and the Air Force Systems Command, USAF, under grant number F49620-93-1-0068.
Sponsored by the National Science Foundation under grant number DDM-9201813. 相似文献
72.
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76.
双环戊二烯的催化氢脂基化制备三环单,双酯 总被引:2,自引:0,他引:2
双环戊二烯(DCPD)通过均相催化与一氧化碳及乙醇或甲醇反应生成四种三环单酯或三种三环双酯,其反应式如下: 相似文献
77.
液相色谱法测定地质样品中的芳香化合物 总被引:1,自引:0,他引:1
发展了用液相色谱法检测地质样品中芳香化合物的方法。对观察到的色谱峰进行了定性分析,了该法对油气地球化学勘探的意义。 相似文献
78.
4,4’—二苯甲酰基联苯有两个三岔点,属于二元三岔共轭体系。从结构式上看,卽可把它作为二苯甲酮骨架的取代产物,又可看作是在联苯骨架上的取代。作为系统研究三岔共轭体系结构效应的部分工作,我们用QCFF/PI+MCA(Quantum Mechanical Extension of the Consistent Force Field to PI Electron System+Molecular Crystal Analysis)程序研究了其晶态和孤立态(气态)构象。研究结果表明,在孤立态中,联苯基的二个苯环的最小二乘 相似文献
79.
超声波辐射下的固—液相转移催化法合成苯乙酰基芳基硫脲化合物 总被引:2,自引:0,他引:2
合成酸基硫减类化合物常用的方法是固一液相转移催化法“‘.因超声波辐射可以加快有机合成反应,提高产率,本文采用了超声波辐射与相转移催化相结合的方法,以聚乙二醇一400(PEG-400)为催化剂,二氯甲烷为溶剂,在常温下合成了10种N一苯乙酸基一N‘一芳基硫腺新化合物,产率大部分比相应的相转移催化法合成高.本法条件温和、操作简便、产率较高.仪器为CQ-250型超声波清洗器,频率33土2kHZ;PE1730FT-IR红外光谱仪,溪化钾压片;BRUKERAC七0核磁共振仪,CDCI。为溶剂,TMS为内标;PE-2400CHN元素分析仪.化合物(皿… 相似文献
80.
Iron speciation related to color of Jurassic sedimentary rocks in Turpan Basin, northwest China 总被引:1,自引:0,他引:1
Guodong Zheng Bihong Fu Yi Duan Qi Wang M. Matsuo B. Takano 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(2):421-427
Mesozoic-Cenozoic reddish and green beds are widely distributed in northwest China. Mössbauer spectroscopy revealed that the composition of iron species varies with color in the middle-upper Jurassic sedimentary rocks from the Turpan Basin. Three main kinds of iron species were identified: (1) ferric iron of hematite (hem-Fe3+), (2) paramagnetic ferric iron (para-Fe3+), and (3) paramagnetic ferrous iron (para-Fe2+). Pyrite iron (pyr-Fe2+) was revealed only in a few samples. In general, there is a direct correlation between rock color, iron species and total iron content, however, in detail, this relationship is more complicated. The reddish rocks contain higher contents of total iron and hem-Fe3+, whereas the gray rocks contain much more para-Fe2+. However, relatively low hematite content cannot give red color to rocks, probably due to suppression by other pigments such as organic matter in black or chlorite in green. The dark or green rocks normally contain either only paramagnetic Fe2+ and paramagnetic Fe3+ species or these two species associated with hematite Fe3+, but the relative content of hematite species is lower. The variations of different iron species control lithological properties such as color and also may reflect the sedimentary conditions. Moreover, iron speciation in these rocks is one of the main factors, which result the color features of rocks in remote sensing imagery.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献