首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1426篇
  免费   50篇
  国内免费   10篇
财政金融   13篇
工业经济   87篇
计划管理   720篇
经济学   106篇
综合类   72篇
运输经济   221篇
旅游经济   16篇
贸易经济   136篇
农业经济   22篇
经济概况   93篇
  2024年   10篇
  2023年   21篇
  2022年   24篇
  2021年   36篇
  2020年   49篇
  2019年   21篇
  2018年   19篇
  2017年   37篇
  2016年   36篇
  2015年   56篇
  2014年   156篇
  2013年   101篇
  2012年   138篇
  2011年   156篇
  2010年   115篇
  2009年   63篇
  2008年   111篇
  2007年   107篇
  2006年   60篇
  2005年   45篇
  2004年   37篇
  2003年   36篇
  2002年   11篇
  2001年   14篇
  2000年   6篇
  1999年   7篇
  1998年   4篇
  1996年   1篇
  1995年   2篇
  1994年   2篇
  1993年   1篇
  1987年   1篇
  1984年   1篇
  1982年   1篇
  1979年   1篇
排序方式: 共有1486条查询结果,搜索用时 15 毫秒
31.
交通政策实践分析表明,京沪两市目前交通实践主要集中于交通供给政策,交通需求政策和空间政策实施力度不够,这与发达国家大城市交通实践形成鲜明对比,也导致了京沪城市交通效率低下.两市交通政策的最大差别在于对个体机动车辆的控制方面,上海通过私家车牌照拍卖,在一定程度上控制了小汽车的增长速度,而北京由于缺乏有效举措导致小汽车过快增长,这一政策差别是两市交通效率差异的主要原因.通过京沪交通比较研究,就我国特大城市交通战略的未来走向提出相应的政策建议,以期为城市交通发展决策提供参考依据.  相似文献   
32.
对影响客户选择物流运输产品的因素进行了分析,在此基础上运用模糊综合评价法对物流企业运输产品的市场效果进行评价。  相似文献   
33.
煤炭运输方式的经济性问题是制定能源产业政策的基本理论问题之一,为此回顾了我国五十年代以来的部分有关研究工作,对不同时期的部分研究实例从研究方法、技术方案和研究结论三个方面进行了对比分析,揭示了不同研究工作在基本原理方面的一致性和技术方案方面的差异性,以及由此造成的研究结论的异同。  相似文献   
34.
对石油资源价值评价中的4个成本因素之一——运销成本级差因素进行了讨论。文中分析了运销成本级差因素的组成因子之后.建立对之进行测算的数学模型,并就两个油田的实测数据给出了计算结果。  相似文献   
35.
The Essential Air Service Program (EAS) has attracted considerable criticism and has been a target for either modification or complete termination almost since its inception through the Airline Deregulation Act in 1978. Although its opponents emphasize the program's inefficiency, its supporters claim that the program is crucial to accessing small and remote communities, which helps them develop economically and socially. This paper demonstrates the economic contributions of EAS flights to small and remote communities. Using a two-stage least squares estimation, the major findings indicate that a 1% increase in air passenger traffic in EAS airports with a minimum annual air passenger traffic of 1000 likely leads to a 0.12% increase in per capita income of the community served by that airport. Our results also suggest that EAS communities that are able to sustain their subsidized flights experienced higher per capita income growth in the 1999–2011 period than did ex-EAS communities that lost their flights as a result of non-eligibility.  相似文献   
36.
The main objective of this study is to investigate the inclusion of lateral transhipment opportunities into the humanitarian relief chain and to examine the effect of different parameters on minimizing the average distance travelled per item while serving the beneficiaries. Direct shipment model (DT), lateral transhipment model (LTSP) and maritime lateral transhipment model (MLTSP) are developed and compared between each other by using a real life earthquake scenario prepared for the city of Istanbul by JICA (Japanese International Cooperation Agency). Developed mathematical models decide on the locations and number of disaster relief facilities, quantity of relief items to hold at those facilities, and quantity of lateral transhipment between the facilities. Vulnerability of the roads and heterogeneous capacitated facilities are also considered. It can be concluded that both LTSP and MLTSP models gave better results than DT model and lateral transhipment option helps beneficiaries to obtain relief items faster and with higher service level.  相似文献   
37.
王昌豪 《价值工程》2014,(32):67-68
当支架工作一定时间后出井维护时,需要将前梁与顶梁之间的销轴拿掉后改为运输销轴连接,由于井底空间、设备有限,操作极为不便;另外,由于前梁千斤顶是靠销轴受力,因为支架工作时间比较长且井下环境恶劣,导致销轴出现变形、生锈等现象,以致销轴不易拆卸。  相似文献   
38.
考虑了牵引车空驶、带空挂车行驶和带重挂车行驶所引起的成本差异,定义了牵引车运行成本的概念,将总运行成本最小作为调度方案优劣的判别指标,并同时考虑牵引车数量最少。将牵引任务分为四种类型,定义了任务链、虚拟任务、链内交叉和链间交叉的概念,提出了一种求解该类单车场甩挂运输车辆调度无时间窗约束的启发式算法,包括初始调运方案、链内优化、空车调运交叉、牵引车数量优化和链间交叉。最后给出了仿真算例,算法优化后的最终方案与初始方案相比,牵引车数量减少,总运行成本降低,验证了算法的有效性和可行性。  相似文献   
39.
Transportation literature is shifting its focus from passengers’ perception of transit quality to understanding passenger experience from a holistic perspective. Few studies have investigated passenger experience factors from a holistic perspective; however, they are explored independently. A holistic approach can help the transport service providers to understand the complete journey of the passenger. This study proposes the concept of holistic passenger experience (HPX) and identifies the determinants of HPX in the context of public transportation with specific reference to Indian Railways. The study develops a comprehensive scale that measures the influence of these determinants on HPX to address this gap. Following a systematic scale development process, this study identified and validated (content, construct, convergent, and discriminant validity) a seven factor structure scale that determines HPX. Of these seven factors, four factors (vehicle maintenance, comfort & security, off board service, and travel information) constitute the core services offered by the transport service provider. Interestingly these four factors can be effectively managed by the service provider. The other three factors (social environment, supporting services, and accessibility) cannot be entirely managed by the transport service provider effectively, as these factors fall beyond the scope of the service provider.Nomological validity results are explained by constructing a matrix (holistic passenger experience Matrix) which reveals that most of the constructs that are can be managed by the transport service provider can be mapped to the cognitive component of customer experience, whereas most of the factors which go beyond the scope of the transport service provider could be mapped to the emotional component of customer experience. The findings can assist the transport sector executives to identify the key determinants to deliver superior passenger experiences throughout the journey.  相似文献   
40.
The main objective of this article is to evaluate determinants of demand for light fuels in Brazil between 2003 and 2013. Through a vector autoregression analysis, an effort was made to identify and quantify the impact of different economic variables and public policy measures adopted during this period on the surprising increase in energy consumption by Brazil’s light-vehicle fleet. The results suggest that demand for energy by the light-vehicle fleet was influenced by an increase in income, by a decrease in fuel prices associated with a policy designed to prevent increases in the price of gasoline from pushing the inflation rate up, by a higher availability of credit for buying vehicles, and by a drop in the real price of those goods, with emphasis on countercyclical measures to waive the tax on industrialized products levied on new vehicles during economic downturns in the automotive industry.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号