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301.
就车辆动态时间最短路径诱导问题展开研究,提出了一种便于工程实施的变起点、定目标点的动态行程时间最短路径规划方案. 基于该方案,在一种大型方阵图下,就Dijkstra、A*、D* Lite等几种动态路径规划算法的计算时间进行了对比分析,针对车载动态导航设备实时性要求高、计算量要求尽可能小的特点,提出了一种基于路网变化的跳变的动态路径规划策略,根据路网中路段权值变化的具体情况,选取更加节省时间的搜索方式. 利用东莞市区电子地图和路网历史流量数据进行实验,实验结果表明,该策略可以有效减少路径动态规划的计算时间,有一定的工程应用价值. 相似文献
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Objective To investigate the effect of oleanolic acid (OA) on apoptosis, correlation between apoptosis and intracellular calcium, and its mechanism in human lung adenocarcinoma cell line A549. Methods Human lung adenocarcinoma A549 cells were incubated in vitro and assigned with OA concentrations of 0, 10, 20 and 40μg/mL. The apoptosis status of A549 cell line was detected with Annexin V-FITC/PI by flow cytometry (FCM); fluorescence intensity (FI) of A549 cells was assessed and the level of intracellular calcium was calculated at 24 hour of OA intervention. The relation between apoptosis and calcium FI was illustrated by curve fitting. Results FCM showed that 10, 20 and 40μg/mL of OA could induce A549 cell apoptosis, which followed a concentration-effect pattern; 24-hour intervention with 20μg/mL and 40μg/mL OA showed increased A549 cell apoptosis, and was significantly different from that with 0μg/mL OA (P<0.01). The FI of intracellular calcium concentration in 10, 20 and 40μg/mL OA groups was significantly higher than that in 0μg/mL group after 24 hours' intervention, and the FI showed a trend of increase with increased OA concentration (P<0.01). Curve fitting showed a significant correlation between apoptosis rate and intracellular calcium concentration in A549 cells (r=0.981, P<0.01). Regression equation was Y=0.508X-1.627. Conclusion OA plays a role in inducing apoptosis of human lung adenocarcinoma cells in a concentration-dependent manner. The OA-induced apoptosis is responsible for intracellular calcium overload of the tumor. 相似文献
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The paper presents methodological overview of the application of Multiple Criteria Decision Making/Aiding (MCDM/A) in public transportation. It explains why MCDM/A methodology is so important while dealing with different categories of decision problems that arise in mass transit systems. Major features and basic notions of MCDM/A methodology are presented. Different categories of MCDM/A methods are characterized and classified. Two case studies demonstrate possible applications of MCDM/A methodology in public transportation. In the first case study multiple objective evaluation of the mass transit system developments' scenarios is carried out. Four variants of the mass transit system are evaluated by a consistent family of criteria with an application of ELECTRE III method. The second case study refers to optimization of the crew size in the mass transit system operated by a public transportation company (PTC). Multiple objective mathematical programing problem is formulated and solved by a combination of an original, customized heuristic procedure implemented in a computer software PEOPLE and the Light Beam Search (LBS) method. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
306.
洞诺融江大桥是广西三江至柳州高速公路的重要工程之一。文章通过对洞诺融江大桥的桥型进行多方案设计,对预应力混凝土连续刚构桥和独塔双索面预应力混凝土矮塔斜拉桥这两个桥型方案进行综合比较,最后采用了施工工艺成熟、造价低及后期养护简单、费用较少的主桥70+125+70m预应力混凝土连续刚构方案。 相似文献
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在对机械振动和内耗理论进行分析的基础上,设计并研制出球墨铸铁音频检测仪。利用所研制的仪器可同时测出球铁铸件在脉冲激振条件下的两个音频参数-共振频率及内耗值,进而预测出球铁的石墨状况、基体组织类型。经生产现场试用表明,该仪器的复现性好,实测相对误差≤1.0%;采样时间〈500μs。 相似文献
308.
周安德 《电力机车与城轨车辆》2003,26(5):34-36,41
以16位单片机80C196MC为主控制器,采用实时的算法,用MCS96汇编语言编写程序,在ICES-16仿真器上成功实现实时的PWM仿真。 相似文献
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