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511.
计算机编制客运专线周期列车运行图问题已成为国内外研究的热点问题之一.在充分研究国内外周期与非周期列车运行图的规划理论与方法的基础上,构建了我国客运专线周期列车运行图的多目标模型,并将之转化为具有优先级结构的单目标模型;然后结合运行图的数学本质与周期性,设计了基于Job-shop的遗传算法,弥补了国外基于PESP理论所开发的周期列车运行图的算法不足.最后结合京津客运专线实例来验证算法的有效性. 相似文献
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V. A. Knyazik A. S. Shteinberg V. I. Gorovenko 《Journal of Thermal Analysis and Calorimetry》1993,40(1):363-371
A new thermoanalytikal method, called electrothermal explosion (ETE) is described in which uniform heating of samples at extremely high rates (up to 105 deg. sec?1) is achieved. Heating is by direct passing of an electric current through the sample in the initial stages and by chemical heat release after the ignition conditions have been attained. ETE is the only direct method that allows the macrokinetics of heterogeneous reactions occurring in condensed systems to be studied at high temperature and at short conversion times, which are prohibitive for traditional thermoanalytical devices (up to 3500 K and 10?2 sec respectively). Kinetic data on high-temperature, high-speed interactions in powder mixtures of carbon with titanium, silicon and tantalum are presented. The rate of heat release in the Ti?C system depends only to a small extent on temperature after the metal has melted, being mainly determined by the solution rate of carbon particles. The interaction mechanism in the Si?C system is similar to that in Ti?C, but the high enthalpy of carbon solution in liquid silicon results in a bulk activation energy ofE=55 kcal. mol?1. Synthesis of tantalum carbide from the elements in the temperature range 1500–3000 K occurs by the mechanism of reaction diffusion and proceeds with strong self-retardation. 相似文献
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Guan-Wu Wang Ting-Hu ZhangYu-Jin Li Ping LuHuan Zhan You-Cheng Liu Yasujiro MurataKoichi Komatsu 《Tetrahedron letters》2003,44(23):4407-4409
Inorganic base, Na2CO3, was utilized to replace organic base, DBU, in the Bingel reaction employing diethyl bromomalonate under the mechanochemical ‘high-speed vibration milling’ conditions to give the cyclopropanated C601 in high yield. In contrast, reactions of C60 with diethyl malonate and ethyl acetoacetate in the presence of Na2CO3 under HSVM conditions afforded 1,4-bisadduct 2 and dihydrofuran-fused C60 derivative 3, respectively. 相似文献
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用于高速可压缩流体分析的带多维耗散格式的自适应Delaunay三角剖分 总被引:2,自引:1,他引:1
利用自适应Delaunay三角剖分并结合胞格中心迎风算法,分析非粘滞高速可压缩流体问题.推导了多维耗散格式,并采用非结构化三角网格的迎风算法,改善了激波的计算结果.解精度评价中引入误差估计,在网格重划分算法中,解梯度变化大的区域生成小单元格,解梯度变化小的区域使用大单元格.该格式能进一步推广到高阶时空的解精度分析中.通过稳态和不稳态的高速可压缩流体超音速激波和激波传播特性的分析,可以评估该算法的效率. 相似文献
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Ángel Marín 《TOP》2007,15(2):231-241
The rapid transit network design problem consists of the location of train alignments and stations, in a context where the
demand makes its own decisions about the mode and route. The originality of this study is to incorporate in the model the
line locations constraints with a bounded but variable number of lines, and lines with no predetermined origins and destinations.
The computational experiments show the necessity of this extension to solve large networks, principally because of its computational
advantage.
The project has been supported by Ministerio de Educación y Ciencia (Spain) under project TRA-2005-09068-C03-01/MODAL, and
by Ministerio de Fomento (Spain) under project 2005/70029/T05. 相似文献
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