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151.
152.
为促进"十四五"期我国城市交通无障碍环境建设,系统梳理我国城市交通无障碍发展的现状和问题,基于对"十四五"期城市交通无障碍发展形势需求的分析研判,提出相应的政策建议.研究认为:"十四五"期,我国城市交通无障碍发展将面临人口老龄化、新型城镇化、需求品质化、交通智能化的多重趋势叠加,需坚持新发展理念,加快供给侧改革和需求侧管理双向发力,从完善顶层制度设计、推广普及通用设计、完善慢行交通体系、推动无障碍公交认证、加强日常维护管理、提升出行服务水平、加大资金用地保障和营造无障碍出行文化等方面采取对策,推进城市交通无障碍建设高质量发展. 相似文献
153.
Chin-Shan Lu Chih-Ching Chang Yung-Hao Hsu Prakash Metaparti 《Maritime Policy and Management》2013,40(7):663-665
The terrorist attacks of 11 September 2001 heightened awareness about the vulnerability of all modes of transportation to terrorist attack. The issue of maritime security has therefore become a major concern in the international maritime sector over the past several years. Globalization has led to a strong growth in seaborne trade; however, it simultaneously increases vulnerability to not only terrorism but also international criminal activities that threaten the world's supply chain. For example, in 2008, the rise in piracy activities in the Gulf of Aden brought the issue of maritime security to the forefront of international debate. In addition to the direct impact on ships, crews and cargoes, and on the maritime industry and governments, piracy also threatens global seaborne trade, and has an impact on energy security and the environment [UNCTAD, 2009, Review of Maritime Transport 2009 (New York: United Nations)]. Maritime piracy can pose substantial risks to seaborne trades, with considerable commodities, ranging between raw materials and energy to high-value manufactured products, being shipped between global economic powerhouses [FU, X. W., NG, A. K. Y., LAU, Y. Y., forthcoming, The impacts of maritime piracy on global economic development: The case of Somalia. Maritime Policy and Management]. Maritime security management, including the definition of security, maritime risk assessment, security measures, the regulation and policy of maritime security in shipping and port-related business operations has been receiving growing attention, both in practice and research. 相似文献
154.
早期建设的山区T梁桥、空心板桥由于不能满足急剧增长的交通需求必须拓宽。从荷载横向分布系数入手,利用梁格法分析不同拓宽方式对中小跨径桥梁内力的影响。研究表明:合理的拓宽方案可有效降低旧桥梁体承担的荷载,间接提高旧桥承载裕度,达到少加固或不加固即能满足拓宽提载的要求,有效减少加固费用。 相似文献
155.
针对城市道路环境中驾驶人的应激响应操作时间特性,基于虚拟现实技术搭建了测试平台,对28名驾驶人在不同应激场景下的应激操作时间进行了研究.不同应激场景下的数据分析结果表明,非熟练驾驶人的应激操作时间要小于熟练驾驶人,且时间值较为稳定.青年驾驶人的操作时间值最小,且数据最为稳定.此外,随着车速的上升,驾驶人操作时间呈现下降趋势,两者之间符合对数函数关系.以驾驶经验、驾驶人年龄和车速为自变量,采用对数函数的多元线性预测模型能够对驾驶人的应激操作时间进行准确预测,被试样本实测值落在预测区间的比例达到了98.37%. 相似文献
156.
首先总结了建立高速公路建设贯彻国防要求目录管理体系的必要性,进而从分析目录管理体系的内容入手,概括了目录管理体系的内容要点,并提出了针对建立目录管理体系的三个方面的做法建议,对于明确解释高速公路建设贯彻国防要求目录管理体系建立过程中的一些问题具有一定的参考价值。 相似文献
157.
Abstract This paper investigates the routing of pressurized tank trailers and proposes a scheduling plan which ensures the practical delivery of industrial gases under the objective of reducing transportation costs. Using constraint programming, we solve a combinatorial optimization problem that incorporates both hard and soft constraints for routing and scheduling tank trailers. Hard constraints are resource and safety/regulation constraints, whereas soft constraints are utilization and efficiency constraints. This approach enables tank-trailer routing and scheduling management to consider different combinations of parameters and view the results in ‘real-time.’ The routing and scheduling results based on a case study in Taiwan fulfil the goals of avoiding risks associated with transporting industrial gases, and attaining efficient delivery while conforming to regulations and consistent with good business practice. The results also suggest that significant economies in distribution costs are possible. 相似文献
158.
Abstract This paper presents a novel application of a Method of Inequality-based Multi-objective Genetic Algorithm (MMGA) to generate an efficient time-effective multi-fleet aircraft routing algorithm in response to the schedule disruption of short-haul flights. It attempts to optimize objective functions involving ground turn-around times, flight connections, flight swaps, total flight delay time and a 30-minute maximum delay time of original schedules. The MMGA approach, which combines a traditional Genetic Algorithm (GA) with a multi-objective optimization method, can address multiple objectives at the same time, then explore the optimal solution. The airline schedule disruption management problem is traditionally solved by Operations Research (OR) techniques that always require a precise mathematical model. However, airline operations involve too many factors that must be considered dynamically, making a precise mathematical model difficult to define. Experimental results based on a real airline flight schedule demonstrate that the proposed method, Multi-objective Optimization Airline Disruption Management by GA, can recover the perturbation efficiently within a very short time. Our results further demonstrate that the application can yield high quality solutions quickly and, consequently, has potential to be employed as a real-time decision support tool for practical complex airline operations. 相似文献
159.
通过对正交异性钢箱梁桥面结构作适当简化,用平面刚架结构分析了桥面板的受力,揭示了桥面结构的受力特点,可作为钢箱梁结构设计和结构优化的参考。 相似文献
160.