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101.
城市公交停靠站选址与平面布置优化   总被引:1,自引:0,他引:1  
公交停靠站是公交车运行当中的重要节点,在城市主要地段人口密集区域,公交使用者的出行便利程度作为公交车停靠站站点选址的重要考量指标。在此基础上利用重心法定量分析及结合站点周围用地性质、客流量等多项指标进行定量分析提出一个公交停靠站微观选址模型并优化现有停靠站的布置形式,这对于新建以及现有公交停靠站的站点微观位置和平面布置都将具有一定的现实指导意义。  相似文献   
102.
以3000m深水工程勘察船(“海洋石油708”)为实例,介绍了挪威船级社(DNV)NAUT-OSV船级符号对电气系统的设计要求.结合实船试航过程中发现的问题,指出了系统设计、设备订货和船舶施工过程中的要点.  相似文献   
103.
吴乐 《隧道建设》2012,32(6):892-895,906
为了解决由于单护盾TBM掘进刀盘扭矩过大或盾体姿态发生偏差时,管片在掘进过程中产生旋转,造成管片安装精度、外观质量及运输效率受到影响等问题,结合单护盾TBM在软岩地层掘进条件下,分析管片旋转产生的原因,针对刀盘等设备的结构进行设计改进、优化掘进参数、优选刀具类型、及时清理刀盘以及必要时采取牺牲管片环缝与纵缝等措施,最终解决了单护盾TBM掘进过程中管片旋转的施工难题。  相似文献   
104.
This article provides a multi-scale analysis of the links between commuting patterns and urban form by using both morphological and more classical indicators of urban form (like density). Thirteen French urban areas of more than 500,000 inhabitants (excluding Paris) are compared. The findings highlight the complexity of the links between urban form and commuting patterns because the same indicators of urban form do not have the same influence according to the spatial scale. Even if the influence of the morphological indicators is lower than that of more classical socioeconomic variables (income level, motorization rate), our study discusses the various and multi-scale consequences of urban development on daily travel behaviour.  相似文献   
105.
某轿车悬架系统的载荷仿真分析   总被引:1,自引:0,他引:1  
基于多体动力学理论建立了某型轿车后悬架的刚柔耦合动力学模型,将采集的某试车场比利时路面不平度信号作为路面激励输入,对悬架系统进行了动态仿真,并用已有道路试验数据,包括后桥垂向加速度和悬架动行程验证了模型的正确性.最后,基于经验证的悬架动力学模型,对关键部件的受力状况进行了全面仿真,确定了悬架系统各部件承受的主要载荷形式,可为悬架系统载荷谱采集测点的选取提供参考.  相似文献   
106.
路由器互联端口运用安全策略,有效拦截病毒的传播 在网关路由器、三层交换机上实行ARPA绑定,瓦解ARP病毒的攻击,实用效果良好。在计费UNIX主机上编写的程序,查出实时采集丢失的原始话单,保证原始话单无损到达计费系统,带来的经济效益显著。  相似文献   
107.
Agent-based approach is a popular tool for modelling and developing large-scale distributed systems such as urban traffic control system with dynamic traffic flows. This study proposes a multi-agent-based approach to optimize urban traffic network signal control, which utilizes a mathematical programming method to optimize the signal timing plans at intersections. To improve the overall network efficiency, we develop an online agent-based signal coordination scheme, underpinned by the communication among different intersection control agents. In addition, the initial coordination scheme that pre-adjusts the offsets between the intersections is developed based on the historical demand information. Comparison and sensitivity analysis are conducted to evaluate the performance of the proposed method on a customized traffic simulation platform using MATLAB and VISSIM. Simulation results indicate that the proposed method can effectively avoid network oversaturation and thus reduces average travel delay and improves average vehicle speed, as compared to rule-based multi-agent signal control methods.  相似文献   
108.
该文以某地下车库工程为实例,介绍了基坑施工在管线穿越的情况下,采用高压摆喷桩和SMW工法相结合的围护设计、型钢支架架空管线的方案,以及支撑拆除过程中的管线保护措施,有效地保护了管线,降低了建设的成本,加快了工程的进度。  相似文献   
109.
This study investigates how air traffic emissions taxes may impact carbon emissions in the US. The magnitude of emissions savings in the US domestic airline industry that would result from lower demand for air travel as taxes are levied and air fares increase is estimated. At the same time, the air-automobile substitution effect is considered and it is argued that some air travelers may divert to automobiles, thus increasing automobile carbon emissions. Both the analysis of the aggregate US domestic airline industry and the study of a sample of US domestic route markets indicate that potentially sizeable increases in automobile traffic and related emissions may substantially reduce the environmental benefits of air travel carbon emissions taxes. In some instances, carbon emissions may even increase in short-haul markets. Sensitivity analyses are performed to demonstrate the robustness of these findings.  相似文献   
110.
Access to current, comprehensive, and reliable spatial information is necessary for informed decision making in integrated coastal and ocean management. This need is being met through development of a marine spatial information infrastructure that encompasses both technological and institutional responses. This article traces Canada's experience in developing a marine spatial information infrastructure over the last 30 years starting with the compilation of coastal atlases, through the development of geographic information systems, to remote data acquisition instruments and Web mapping portals. Because of the plethora of initiatives, it has been essential to be selected and limit the number and choice of examples. The institutional response has lagged behind that of technological innovation and hinges on understanding users’ needs and decision support drivers, sustainability of institutional and individual champions, and, above all, cooperation and collaboration among the broad community of practice.  相似文献   
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