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181.
近年来,随着我国工业化和城镇化进程的加快,能源消费和能源供给连创新高,但供需矛盾日益尖锐,环境压力日趋加大.能源审计作为一种新型的能源科学管理和节能减排方法,在我国尚未广泛开展.其主要原因是政府面临强制性需求与企业自愿性需求不匹配,能源审计供给能力不足.促进能源审计发展对策必须要从提高市场需求与增强市场供给两方面入手.  相似文献   
182.
ABSTRACT

With the economic reform in China, the international shipping industry and some academics anticipated, as early as the 1990s, that Chinese seafarers would flood the world’s seafaring labour market. However, China’s seafarer export has been far lower than these expectations. This article seeks to explain this lack of development through research into the management strategies of two major ship crewing agencies in China, which have been reformed to different degrees, and the experience of the seafarers who work for them. To examine this question, 86 interviews of managers and seafarers were conducted in two Chinese state-owned crewing agencies (SCAs) between 2008 and 2013. The studies demonstrate that despite the economic reform in China, the SCAs were still supported and constrained by institutions at higher levels, instead of becoming independent, market-oriented economic entities, which constrained the development of foreign manning business. This partly explains the limited rate of increase of China’s seafarer export.  相似文献   
183.
文中运用风险管理理论,从“人员、船舶、环境、管理”4个方面对长江船舶油污染风险进行分析,并提出了相应管理对策.  相似文献   
184.
Abstract

Planners, engineers and economists have introduced various demand management methods in an attempt to reduce the fast growing traffic congestion. The basic idea behind various demand management strategies is to force drivers to travel and use transportation facilities more during off-peak hours and less during peak hours, as well as to increase the usage of underutilized routes. In this paper, a new demand management concept – Auction-based Congestion Pricing – is proposed and modeled.  相似文献   
185.
本文论述了学习策略和交际策略的概念和分类,以及目前研究表明的影响学习者使用交际策略的一些主要因素,目的在于探讨交际策略的研究在外语习得中的作用和对外语教学的启发。  相似文献   
186.
单点自适应控制策略的时间参数和相位结构研究   总被引:2,自引:0,他引:2  
时间参数和相位结构是单点自适应控制策略的重要参数。介绍了最佳绿灯时间、最小绿灯时间、最大绿灯时间、单位绿灯延长时间、绿灯间隔时间、黄灯时间等的计算和取值方法。参考NEMA标准的双环相位结构,分析了单点自适应控制策略的备选相位切换方案,提出“三阶段”相位切换过程,能灵活地实现相位组合和相位切换,降低相位切换决策方法的复杂程度。  相似文献   
187.
车辆减速策略与跟驰车距具有相互制约的关系.分析了车辆减速运动规律,提出反映人们期望和行为特点的基于双曲函数的车辆减速策略,进而建立计算安全跟驰车距的数学模型,并按照国际载运工具和我国上海磁浮列车的运行舒适性评价标准,对200 km/h跟驰速度条件下安全车距的计算式进行了仿真试验与数值分析,验证了相关数学模型与计算方法的有效性.  相似文献   
188.
城市公共交通优先的信号控制策略   总被引:9,自引:0,他引:9  
城市公共交通优先的信号控制策略研究如何在道路交叉口信号控制中体现公交优先的技术,本文详细阐述了实施公共交通信号优先的硬件系统和具体的实现策略。为了有效地在路口信号控制系统中体现公交优先策略,在控制过程中要采用实时算法,将公交优先作为信号控制的一个函数,论文给出了交叉口公共交通优先策略的实时最小绿灯持续时间估计。作者在交通控制的模拟中采用了该控制策略,结果表明:公共交通优先信号控制系统的设计和实施能够提高公共交通的行驶速度和公交运行的可靠性。  相似文献   
189.
Automatic two-dimensional layout using a rule-based heuristic algorithm   总被引:1,自引:0,他引:1  
 Efficient layout strategies are introduced for automatic nesting using a rule-based heuristic approach to improve the layout efficiency. Since a large portion of the complexity of the parts layout problem results from the overlapping computation, geometric redesign techniques are also suggested to reduce the complexity of the problem for a fast and reliable means of performing overlapping computation. A new heuristic sliding technique is developed to find a near-optimum layout location from all the feasible arrangements in such a manner that two or more arbitrary parts do not overlap or intersect. An identification method with a pivoting point is suggested to calculate the boundary of the overlap region in a fast computation time-frame. Resource plate clipping using virtual memory, based on a polygon clipping algorithm, is also proposed as a technique to reduce the geometric conditions of the resource plate and the overlap computation time by updating a new stock boundary of the resource plate for the layout space of the next part after each part is placed. The aim of this article is to develop a rule-based heuristic nesting system to achieve a new automatic layout on the AutoCAD system. For this implementation, some nesting examples are demonstrated. A rule-based heuristic approach can be desirable in terms of the layout efficiency and considering the computational time for nesting problems, and is proposed as a real-time layout simulation method in the industrial field. Received: October 7, 2002 / Accepted: March 27, 2003 RID="*"  相似文献   
190.
宋键 《都市快轨交通》2009,22(2):19--23
采用轨道交通客运交通方式,是实施城市交通节能的重要举措,是落实国家节能政策的具体体现.基于城市轨道交通二次节能,结合城市轨道交通能耗特点与实施节能的背景,提出上海城市轨道交通"十一五"实施节能的目标与策略,包括工作思路、能耗指标体系、网络总体节能目标、运营线路节能分解目标、实施节能基本对策与工作体系,着重对城市轨道交通节能实施策略,重点节能技术的应用、试点与研发进行系统阐述.  相似文献   
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