排序方式: 共有78条查询结果,搜索用时 8 毫秒
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为了提高粒子群优化算法(PSO)寻优过程中粒子种群之间的多样性,提出了一种基于停滞判断准则与粒子速度更新的改进PSO。在寻优过程中,当粒子群优化陷入停滞时,新的速度更新公式将激活,提高粒子种群之间的多样性。通过数学标准测试函数,进行了数学实验,对比改进PSO与标准PSO的优化能力。结合近似建模技术与合理的约束处理方法,将该算法运用到考虑100%正面碰撞工况、40%偏置碰撞工况、侧面碰撞工况、追尾碰撞工况以及顶压溃工况的车身轻量化设计中。结果表明:在全局寻优能力方面,运用改进PSO优化得到的问题解均优于标准PSO。在满足各项结构性能指标的前提下,可减轻质量23.41 kg。这为轿车车身轻量化设计提供了可借鉴的方法。 相似文献
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Surrogate models are commonly used for approximation of large computationally expensive vehicle crash simulation to facilitate rapid design space exploration and optimization. Unfortunately, the optimum design based on surrogates may turn out to be infeasible after running finite element crash simulation due to the surrogate errors. To meet this challenge, conservative strategy of surrogate modeling through compensating fitting errors was used for reliability based design optimization of vehicle structures for crashworthiness and weight reduction. The critical crash responses were constructed by unbiased kriging models, and conservative surrogates were obtained via adding safety margin to estimate the crash responses conservatively. The benefits of using conservative surrogates for reliability based design optimization were investigated in the context of constraint feasibility of the optimum designs through a mathematical example and a case study on vehicle crashworthiness design. The results demonstrate that optimization based on conservative surrogate helps to achieve the feasible optimum design, showing more attractive for reliability based design optimization in engineering applications. 相似文献
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HAN Shan-ling 《上海交通大学学报(英文版)》2005,10(4):373-376
IntroductionThe lattice Boltzmann method (LBM)[1],which was proposed a decade ago, has attractedgreat attention as an alternative numerical methodfor simulating complex fluid flows[2~5]. Unlikeconventional numerical schemes based on dis-cretizations of macroscopic continuum equations,the lattice Boltzmann method is based on micro-scopic models and mesoscopic kinetic equations.This method was proved to achieve second-orderaccuracy in the domain of the fluid both theoreti-cally and numerically… 相似文献
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为了加强管理,确保水路运输企业经营资质水平不至于下降,危及经营合法性与运输安全,自2004年4月1日起,绍兴市航运管理处对辖区水运企业的经营资质通过定期检查、分级预警来实施动态管理。 相似文献
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据嵊州港航部门最新统计资料显示,到11月底,全市水路运力4603载重吨,货运船舶平均载重吨达到76.7t,比2004年底的43t增长78.4%。其中,100吨级以上船舶的数量由2004年的5艘增加到19艘,吨位占到总运力的 相似文献
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自2005年10月15日到2006年6月30日,杭甬运河富陵大桥将实施建造工程。为确保施工作业顺利进行和船舶航行安全,期间,该大桥北侧水域将实施交通管制。 相似文献
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通过深层土体位移观测在真空预压加固过程中不同深度、不同距离的土层向加固场地内的水平位移量、水平位移随深度及时间不同的变化。 相似文献
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