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1.
发动机曲轴弯扭复合疲劳强度的试验评估方法   总被引:1,自引:0,他引:1  
冯美斌  李满良 《汽车工程》1997,19(3):165-169
本文叙述了曲轴弯矩复合疲劳强度的实验评估方法,其中包括试验装置,弯矩扭矩比的选定和安全系数估算,并给出了应用实例。  相似文献   
2.
针对太旧高速公路路面工程的特点,从调研、选型、购置、使用等方面对国产设备替代进口设备完成路面施工任务的可行性和必要性进行了详细的阐述  相似文献   
3.
Ramp meters in the Twin Cities have been the subject of a recent test of their effectiveness, involving turning them off for eight weeks. This paper analyzes the results with and without ramp metering for several representative freeways during the afternoon peak period. Seven performance measures: mobility, equity, productivity, consumers’ surplus, accessibility, travel time variation and travel demand responses are compared. It is found that ramp meters are particularly helpful for long trips relative to short trips. Ramp metering, while generally beneficial to freeway segments, may not improve trip travel times (including ramp delays). The reduction in travel time variation comprises another benefit from ramp meters. Non-work trips and work trips respond differently to ramp meters. The results are mixed, suggesting a more refined ramp control algorithm, which explicitly considers ramp delay, is in order.  相似文献   
4.
为贯彻全国铁路工作会议精神,落实铁科院工作会议部署,总结铁道部产品质量监督检验中心2011年工作,分析2012年面临的形势和任务,提出2012年重点工作,以适应新的一年铁路发展对质检工作的新要求、新任务,加快提升质检能力,加强全面风险管理,为铁路发展提供技术基础支持。  相似文献   
5.
王燕 《铁道技术监督》2012,40(10):17-18,26
在介绍企业实施纠正措施和预防措施必要性的基础上,分析实施纠正措施和预防措施过程中存在的主要问题及其形成原因,指出提高纠正措施和预防措施有效性的具体做法。  相似文献   
6.
从加强组织管理和现场跟踪检查,提高人员素质和施工设备质量,重视工地试验室建设,采取有效的质量奖罚措施,提高设计质量等方面较详细地阐述了高速公路现场施工中的质量管理问题。  相似文献   
7.
现代高科技的迅猛发展,在给人类带来巨大利益的同时,也带来了许多令人难以预料的消极影响。其中,环境问题就是人类共同关注的现实问题,文章认为,坚持环境道德中的人类中心原则,才能维护人类与自然环境的关系,以达到人与自然的和谐发展。  相似文献   
8.
航海类专业学生教育与管理的成效,关系到我国航海事业的发展.对航海职业特点和新时期航海类专业学生的特点进行了分析,提出了航海类专业学生教育与管理的目标,同时就目标的实现途径和保证方面进行了探讨.  相似文献   
9.
This research focuses on coral reef health in the South Pacific region, an area of high global coral diversity. Coral reef health surrounding two study sites in Rarotonga, Cook Islands, has been assessed in areas that have not been previously surveyed. Each study site has distinct differences based upon marine management practices. Marine management practices are identified and described and some historical reasons as why they exist are discussed. Data are also presented on the ecological condition (coral coverage, number of coral species, clonal condition, disease, and presence and absence of bioindicators). This interdisciplinary research methodology includes both ecological and social data collection to further understand human- environment interactions. In comparing the reefs with different management practices, I argue that the implementation of traditional marine social institutions as exemplified in this case study of the Ra'ui in Rarotonga, Cook Islands, is an effective conservation management tool and is improving coral reef health. The Ra'ui site has significantly higher species diversity/Mortality Index ( F = 2.63).  相似文献   
10.
Standardized and free-format questionnaires on the state of coastal management were fielded to coastal management practitioners during three workshops and a national feedback and recommendation workshop. The most commonly cited responses were identified for each of 13 political regions and overall trends were identified. Management frameworks frequently included research, community organizing, education, livelihood, resource enhancement, resource protection, regulation, and networking components. Gender issues, documentation, and infrastructure investment were rare. The most commonly perceived environmental problem was illegal/ destructive fishing and its associated overfishing and low fish catch. The most commonly cited socioeconomic problem was the inadequacy of law enforcement. The best monitored variables were usually those related to environmental management: status and change of habitats, resources, and degree of enforcement/patrolling activities. The most common nonregulatory enhancement, aside from environmental education (which is the most popular), was mangrove reforestation. In terms of regulations, the majority of the respondents have reportedly formulated an integrated coastal management plan. In practice, regulating destructive and illegal fishing practices and then the establishment of fish sanctuaries are the next most implemented. The most popular quality-of-life enhancement strategies focused on the improvement of sustainable fishing as a livelihood and on a variety of supplementary livelihoods. The most usual institutional intervention being implemented was the setting up of local community people's organizations. Major factors which may influence success or failure of coastal management and recommendations on research, community organizing and livelihood, legislation and policies, implementation and coordination, and networking are also summarized.  相似文献   
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