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101.
通过对各种价格管制模型的分析,揭示其对成本的依赖性,探讨了在价格管制模型的运用中,加强成本管理的重要性。  相似文献   
102.
随着我国高速铁路里程的逐年提高,既有铁路不仅承担着繁重的营运压力,还面临着较为频繁的大中修工作.为了不影响线路的正常营运,也为了铁路施工安全的考虑,既有铁路的大中修普遍采取天窗点施工的方式.本文主要针对铁路大中修天窗点施工的特点,以典型大中修工程天窗点施工为例,结合现场测量的实际数据,详细分析了施工过程中人工和机械的消...  相似文献   
103.
为降低金属陶瓷摩擦材料的制造成本,介绍了Cu基金属陶瓷摩擦材料成本优化方案,并研究了优化方案对Cu基金属陶瓷摩擦材料性能的影响。研究结果表明,Fe可替代Cu用以降低成本,但Fe的含量不应超过20%;可选用低纯度的天然鳞片状石墨作为润滑组元以降低成本,但其纯度不应低于90%;通过合理选择烧结工艺参数,在保证钢背与金属陶瓷摩擦材料的结合强度不低于金属陶瓷摩擦材料自身的抗剪强度的前提下,可以用“平板”状钢背代替“碗状”钢背来降低成本。  相似文献   
104.
作者通过对铁路建设项目经济评价业务特点的分析,提出了利用计算机辅助经济评价的设计思想,并对运量预测、运营成本计算的算法作了详细讨论。  相似文献   
105.
地铁施工已经进入了微利时代,亏损项目比比皆是。深圳地铁2222标段隧道施工出现了巨额亏损,充分说明了地铁施工也是成本高风险专业施工,并非"金隧银桥"。文章通过全面、系统地分析深圳地铁2222标段施工成本,计算出各项施工成本指标,总结出施工过程中成本风险控制方法,提出了地铁隧道施工成本风险的防范措施。  相似文献   
106.
文章针对我国公路造价管理中存在的管理人员思想意识不强、素质不高、造价审计职能弱化、变更管理不到位、缺乏完善的定额管理体系、信息化水平低下等问题,提出了相应的解决对策,为建设单位加强公路造价管理工作提供参考。  相似文献   
107.
Regulators, policy analysts, automobile manufacturers, environmental groups, and others are debating the merits of policies regarding the development and use of battery-powered electric vehicles (BPEVs). At the crux of this debate is lifecycle cost: the annualized initial vehicle cost, plus annual operating and maintenance costs, plus battery replacement costs. To address this issue of cost, we have developed a detailed model of the performance, energy use, manufacturing cost, retail cost, and lifecycle cost of electric vehicles and comparable gasoline internal-combustion engine vehicles (ICEVs). This effort is an improvement over most previous studies of electric vehicle costs because instead of assuming important parameter values for such variables as vehicle efficiency and battery cost, we model these values in detail. We find that in order for electric vehicles to be cost-competitive with gasoline ICEVs, batteries must have a lower manufacturing cost, and a longer life, than the best lithium-ion and nickel–metal hydride batteries we modeled. We believe that it is most important to reduce the battery manufacturing cost to $100/kWh or less, attain a cycle life of 1200 or more and a calendar life of 12 years or more, and aim for a specific energy of around 100 Wh/kg.  相似文献   
108.
来永 《西部交通科技》2013,(8):106-108,119
建设管理阶段的成本控制,是项目建设管理的重要环节。文章以六寨至河池高速公路№5合同段建设管理工作为例,强调了成本控制在项目建设管理工程中的重要性,分析了影响高速公路工程建设成本和进度的常见问题,探讨了在高速公路建设过程中成本控制的方法及措施。  相似文献   
109.
This paper identifies some implications of the cost of public funds (CF) in public transit subsidization and regulation. Regulation is considered because a monopolistic operator is assumed. A social welfare maximization model is proposed, subject to individual rationality and vehicle capacity constraints. Optimality conditions are provided and a key formula is derived about CF’s role in balancing the need to cover the fixed operation cost through fares on the operator’s side and the effort to maintain the user surplus on the passengers’ side. Major findings from this model’s formulation include: (1) CF determines the extent to which the passengers’ surplus is compromised in order to cover the fixed part of the operating cost, and (2) subsidy is unjustified when CF exceeds the critical shadow price of the financial constraint. Analytical relations are illustrated through numerical examples.  相似文献   
110.
This study provides a comprehensive comparison of well-to-wheel (WTW) energy demand, WTW GHG emissions, and costs for conventional ICE and alternative passenger car powertrains, including full electric, hybrid, and fuel cell powertrains. Vehicle production, operation, maintenance, and disposal are considered, along with a range of hydrogen production processes, electricity mixes, ICE fuels, and battery types. Results are determined based on a reference vehicle, powertrain efficiencies, life cycle inventory data, and cost estimations. Powertrain performance is measured against a gasoline ICE vehicle. Energy carrier and battery production are found to be the largest contributors to WTW energy demand, GHG emissions, and costs; however, electric powertrain performance is highly sensitive to battery specific energy. ICE and full hybrid vehicles using alternative fuels to gasoline, and fuel cell vehicles using natural gas hydrogen production pathways, are the only powertrains which demonstrate reductions in all three evaluation categories simultaneously (i.e., WTW energy demand, emissions, and costs). Overall, however, WTW emission reductions depend more on the energy carrier production pathway than on the powertrain; hence, alternative energy carriers to gasoline for an ICE-based fleet (including hybrids) should be emphasized from a policy perspective in the short-term. This will ease the transition towards a low-emission fleet in Switzerland.  相似文献   
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