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981.
介绍电动汽车空调制冷系统的组成及控制原理,对电动压缩机在电动汽车上的合理选择做出了详细分析。通过电动汽车空调制冷系统选择核心零部件的探究,为电动汽车车内环境控制提供技术支持。  相似文献   
982.
介绍了塞拉门分类、结构及特点,重点阐述了大净开度电动双开塞拉门在BFC6128GBEV6纯电动城市客车上的应用。  相似文献   
983.
交流电力机车三电平逆变器-异步电动机系统采用SVPWM控制时,在低速启动阶段,希望正多边形磁链轨迹尽可能接近圆形,使异步牵引电动机三相对称电压近似正弦,以使启动过程更加平稳.文章分析得出系统在低速、低电压工作区,以增加磁链正多边形边数,减小零电压矢量加入时间的电压空间矢量的合成方法,达到改善系统的低速性能的目的.  相似文献   
984.
This paper formulates force constraints of over-actuated road vehicles. In particular, focus is put on different vehicle configurations provided with electrical drivelines. It is demonstrated that a number of vehicles possesses non-convex tyre and actuator constraints, which have an impact on the way in which the actuators are to be used. By mapping the actuator forces to a space on a global level, the potential of the vehicle motion is investigated for the vehicles studied. It is concluded that vehicles with individual drive, compared with individual brakes only, have a great potential to yaw motion even under strong lateral acceleration.  相似文献   
985.
Quantifying progress in management of marine protected areas (MPAs) is crucial to marine conservation and fisheries management in the Philippines. This study compiles data on the status, occurrence, and management gaps of MPAs through coordination with multiple organizations supporting and guiding MPAs in the Philippines. MPA management effectiveness was measured using a MPA Rating System. Since 2002 the modal MPA rating levels increased from level 1 (initiated) to level 4 (sustained) in 2008/9. This upward trend is attributed to factors that promoted both the establishment and improved management of MPAs. Analysis indicated that: (1) most MPAs struggle with budgetary constraints or lack of sustainable financing and (2) overall the MPAs are being maintained and progressing with notable improvement in management despite a range of difficulties encountered during the implementation process. For MPAs in the Visayan Region for which biophysical data were available, the MPA Rating System was used to assess the effectiveness of local government capacity building on MPA coral reef health. Our results suggest that MPAs with higher ratings are likely to have better reef health conditions.  相似文献   
986.
This article recommends the parallel but separate modeling of nature-based and people-based marine protected areas (MPA) before the design and siting stages of establishing an MPA. Separate but simultaneous modeling of ideal nature and people MPAs permits each to be maximized for its own variables and subsequently compared to identify conflicts and agreements. The case that supports this recommendation is in the Commonwealth of the Bahamas, where the study conducted 572 interviews with people from six traditional settlements in the central Exumas Islands and Cays. The research is focused on why members of these settlements differentially responded to three nearby national MPA proposals.  相似文献   
987.
邹立大 《汽车电器》2014,(11):63-75
介绍本田雅阁2010年款EX2.0L自动档(非导航版)轿车常用电气装置的名称、作用、特点和操作方法等,对与行车安全相关的部分作特别提示。  相似文献   
988.
Much has been written about the usefulness of marine protected areas (MPAs) as a management tool. Their performance has been measured using biological and ecological indicators. However, objectives of management also include economic and social responsibilities. As such, stakeholder objectives in MPA management are frequently incompatible. This has been attributed to the variety of stakeholders with an interest in how MPAs are managed. This article considers the development of a performance indicator hierarchy for the Egadi Islands Marine Reserve, and a multi-criteria approach implemented to define compromise positions between stakeholders in decision-making. Data was obtained from a pairwise comparison survey using the analytic hierarchy process to investigate preferences of stakeholder groups for performance indicators in evaluating marine protected area management. The analysis showed that although there are five key stakeholder groups, none are homogenous in prioritizing performance indicators and that none are clear with respect to what the MPA means for them.  相似文献   
989.
The major barriers to a more widespread introduction of battery electric vehicles (BEVs) beyond early adopters are the limited range, charging limitations, and costly batteries. An important question is therefore where these effects can be most effectively mitigated. An optimization model is developed to estimate the potential for BEVs to replace one of the conventional cars in two-car households and to viably contribute to the households’ driving demand. It uses data from 1 to 3 months of simultaneous GPS logging of the movement patterns for both cars in 64 commuting Swedish two-car households in the Gothenburg region.The results show that, for home charging only, a flexible vehicle use strategy can considerably increase BEV driving and nearly eliminate the unfulfilled driving in the household due to the range and charging limitations with a small battery. The present value of this flexibility is estimated to be on average $6000–$7000 but varies considerably between households. With possible near-future prices for BEVs based on mass production cost estimates, this flexibility makes the total cost of ownership (TCO) for a BEV advantageous in almost all the investigated households compared to a conventional vehicle or a hybrid electric vehicle. Because of the ubiquity of multi-car households in developed economies, these families could be ideal candidates for the initial efforts to enhance BEV adoptions beyond the early adopters. The results of this research can inform the design and marketing of cheaper BEVs with small but enough range and contribute to increased knowledge and awareness of the suitability of BEVs in such households.  相似文献   
990.
在使用SolidWorks软件完成船舶柴油机装配体设计的基础上,再利用其动画制作功能,可实现船舶柴油机的虚拟装配及运动仿真.仿真结果直观、生动、形象,可验证装配序列和装配路径的可行性、分析最佳装配次序、确定最优装配路径,从而缩短柴油机的装配周期和提高柴油机的装配质量.  相似文献   
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