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561.
利用ADAMS/CAR建立了某型五轴半挂车(1+5+5)型的车辆模型,以及不同坡度、不同转弯半径的路面文件。仿真分析了车辆在弯坡路面高速下坡行驶的过程,说明了过程中动荷载变化的原因,统计分析了车辆在不同弯坡的路面上行驶产生的动荷载,找到了动荷载随着坡度、转弯半径的变化规律。可为路面设计和车辆设计时考虑动荷载的变化提供参考。 相似文献
562.
由于现实大药量水下爆炸实验的气泡运动性态,难以很好地利用高速摄影进行拍摄。本文通过自主设计的实验电路,模拟水下电爆炸的各种工况,证明了低电压充放电电路实现水下微型电爆炸的可能性,可以较好地得到水下爆炸后气泡脉动和射流的诸多特性,为揭示水下爆炸气泡运动特性提供了参考。 相似文献
563.
针对舰船水声对抗侦察装备性能参数的不确定性,将灰色系统理论与层次分析法相结合,建立模型对装备效能进行评估。用专家评估分析法确定装备效能评估指标权重,用灰色系统理论建立效能评估模型。以某鱼雷报警声纳为例对模型进行了验证,结果表明该模型能充分利用决策者的判断信息,较为准确地反映实际情况,适用于舰船水声对抗侦察装备效能的评估。 相似文献
564.
The association between light rail transit and satisfactions with travel and life: evidence from Twin Cities 总被引:1,自引:0,他引:1
Jason Cao 《Transportation》2013,40(5):921-933
Rail transit has been touted as a way to enhance livability, quality of life or satisfaction with life (SWL). However, the connections between transit and SWL are mainly conceptual, and little empirical evidence is available in the literature. Using the Hiawatha line in Minneapolis as a case, this study develops structural equations models on a 2011 dataset to explore the impacts of light rail transit (LRT) on SWL. We corroborate that the Hiawatha LRT positively influences SWL through enhanced access to different activities, and through improved transit service, enhanced accessibility, and their impacts on satisfaction with travel. The size of the impacts is marginal. 相似文献
565.
566.
3003铝合金A-TIG焊表面活性剂实验 总被引:1,自引:0,他引:1
对3003铝合金进行交流活性钨极氩弧焊(A-TlG)焊接实验,选用氧化物SiO2,TiO2和卤化物MnCl2,NaCl,CaF2作为活性剂,研究了单一成分表面活性剂对焊接熔深的影响。实验结果表明:涂敷活性剂可以一定程度的增加焊缝熔深;氧化物增加焊缝熔深的作用比卤化物大;TiO2作用最显著,熔深增加约80%,且焊缝无裂纹、气孔、夹渣等缺陷。 相似文献
567.
在分析一个OD对中不同道路之间的交通流量均衡分配的基础上,采用灵敏度分析方法,对其中收费公路费率因素对于交通流量分配变化的影响进行了研究.并用实际算例来说明灵敏度分析方法在并行道路交通分配中的应用,即得出不同并行道路竞争条件下,收费公路费率与其交通流量之间的相互关系. 相似文献
568.
The animal experiment of viscose carbon fiber based C/C composites applied in bone defection intramedullary fixation was carried out in New Zealand white rabbits. The histological observation on the 100th day after surgical operation indicated that the experimental animals recovered well and the bone defect area was reconstructed by new bone trabecula. Immunohistochemical observation of leukocyte common antigen and macrophage suggested that intramedullary fixation materials did not induct any chronic toxicity reactions such as inflammatory reactions, macrophage reactions and formation of granulation tissue. The tissue compatibility of this material was excellent. Meanwhile, the impurity element species and the biological toxic element content of viscose fiber based C/C composites were determined by atomic fluorescence analyzer and inductively coupled plasma atomic emission spectrometry. The results reveal that there are few biological toxic elements in the viscose fiber based C/C composites and it can satisfy the constituent demands of surgical implants. 相似文献
569.
Do changes in neighborhood characteristics lead to changes in travel behavior? A structural equations modeling approach 总被引:5,自引:2,他引:3
Suburban sprawl has been widely criticized for its contribution to auto dependence. Numerous studies have found that residents
in suburban neighborhoods drive more and walk less than their counterparts in traditional environments. However, most studies
confirm only an association between the built environment and travel behavior, and have yet to establish the predominant underlying
causal link: whether neighborhood design independently influences travel behavior or whether preferences for travel options
affect residential choice. That is, residential self-selection may be at work. A few studies have recently addressed the influence
of self-selection. However, our understanding of the causality issue is still immature. To address this issue, this study
took into account individuals’ self-selection by employing a quasi-longitudinal design and by controlling for residential
preferences and travel attitudes. In particular, using data collected from 547 movers currently living in four traditional
neighborhoods and four suburban neighborhoods in Northern California, we developed a structural equations model to investigate
the relationships among changes in the built environment, changes in auto ownership, and changes in travel behavior. The results
provide some encouragement that land-use policies designed to put residents closer to destinations and provide them with alternative
transportation options will actually lead to less driving and more walking.
Xinyu (Jason) Cao is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior. 相似文献
Susan L. HandyEmail: |
Xinyu (Jason) Cao is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior. 相似文献
570.