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991.
992.
ABSTRACT Marketing policies have gained more importance in container shipping as the industry experiences challenges arising from commoditization. Market segmentation is fundamental to marketing policies, yet it needs a detailed analysis in container shipping. Accordingly, this paper aims to explore homogenous customer groups in container shipping by conducting a segmentation analysis, which can help container lines apply more efficient marketing policies. A survey study is conducted on 356 shippers in Turkey. The study develops five reliable and valid selection criteria factors and applies cluster analysis based on the selection criteria factors. The cluster analysis produces a total of six benefit segments which are differentiable. The segments are significantly identified by the demographic characteristics of shippers. The paper suggests several implications for the marketing policies of container lines. 相似文献
993.
Increasing stack heights on container ships and growing volumes of high density cargo have increased the loads and stresses placed on containers, requiring an assessment of current container strength specifications. Growing adoption of terminal automation is also requiring greater standardisation in the codification and marking of containers. However, it is shown that there is widespread misunderstanding of the roles of the IMO and the ISO in regulating and promoting standards in the design, dimensions, ratings, coding, marking and strength of containers. In this paper the legal status of the IMO’s Convention for Safe Containers (CSC) and ISO standards is clarified, and a common container specification framework is developed to assess the extent to which international regulations and standards are aligned. The analysis identifies gaps and inconsistencies between regulations and standards and assesses the impact these have on operations and safety. The study highlights to policy makers anomalies arising from the recent inclusion in the CSC of direct references to ISO standards. Finally, in providing a comprehensive definition of container specifications the paper provides a knowledge base to promote theory building for applied researchers in the field of container technology and operations. 相似文献
994.
充分考虑集装箱货物与集装箱班列在时间和数量方面的匹配关系,以集装箱货物送达目的站的总延误最小为目标,构建集装箱班列时刻表优化的线性混合整数规划模型.采 用Benders分解算法将原问题分解为确定集装箱货物与班列匹配方案的主问题,以及优化班列时刻表的子问题,通过求解子问题的对偶模型不断产生主问题的割平面.为克服割平面有效性较低的缺点,设计改进策略,使每次迭代产生多个割平面同时添加至主问题中.最后,通过算例验证模型和算法的有效性.结果表明:改进策略的运用有效提高了算法的计算效率,利用模型及算法得到的班列时刻表与集装箱货物的数量、时间分布之间具有较好的匹配性,制定的班列时刻表很好地响应了用户需求. 相似文献
995.
将船期延误与重要港口节点的识别问题相结合,通过传播动力学模型,对世界集装箱海运
网络的传播特性进行分析,发现港口节点传播能力与度值满足幂为16.84的幂律分布,具有无标
度特征,且度值与传播影响力的相关性较强。以 SIS(Susceptible-Infected-Susceptible)模型为基
础,结合网络结构特性,比较不同节点传播影响力评估方法发现,节点间最短路径长度是衡量节
点传播能力的一个重要因素。基于引力模型,提出考虑度值、节点核心位置及节点间最短路径长
度的综合取值法,验证了改进引力模型在世界集装箱海运网络节点传播能力评估中的适用性,发
现综合取值法对模型精确度提高有促进作用。研究得到:世界各港口传播影响力排序,为关键港
口的识别提供了不同视角;高传播影响力港口普遍集中在亚洲区域,其次为欧洲地区;高连通性
与高传播影响力无正相关性。 相似文献
996.
This paper investigates intermodal freight transport planning problems among deep-sea terminals and inland terminals in hinterland haulage for a horizontally fully integrated intermodal freight transport operator at the tactical container flow level. An intermodal freight transport network (IFTN) model is first developed to capture the key characteristics of intermodal freight transport such as the modality change phenomena at intermodal terminals, physical capacity constraints of the network, time-dependent transport times on freeways, and time schedules for trains and barges. After that, the intermodal freight transport planning problem is formulated as an optimal intermodal container flow control problem from a system and control perspective with the use of the proposed IFTN model. To deal with the dynamic transport demands and dynamic traffic conditions in the IFTN, a receding horizon intermodal container flow control (RIFC) approach is proposed to control and to reassign intermodal container flows in a receding horizon way. This container flow control approach involves solving linear programming problems and is suited for transport planning on large-sized networks. Both an all-or-nothing approach and the proposed RIFC approach are evaluated through simulation studies. Simulation results show the potential of the proposed RIFC approach. 相似文献
997.
ABSTRACTAccurately estimating fuel consumption of ships is crucial for shipping companies, port authorities, and environmental protection agencies. The bottom-up approach is becoming increasingly popular because it can estimate ship fuel consumption by accounting for ship activity conditions, such as changes in voyage speed, time, and distance; however, its use is still limited when estimating ship fuel consumption. Ship-specific information, such as the daily fuel consumption rate for main and auxiliary engines for every vessel, is expensive to gather, and generally not collected from private shipping companies. To address this research gap, we develop simplified and composite ship fuel consumption models for ocean-going container ships by size using a regression model. To estimate the fuel consumption models for container ships, we rely on ship activity data, including average speed and sailing time, distance, and actual fuel consumption for main and auxiliary engines. This information is obtained from a major container shipping company in Korea. We estimate and validate the parameters associated with fuel consumption for five different container ship sizes, all of which are smaller than the Post-Panamax container ship (15,000 TEU and above). 相似文献
998.
999.
基于最优线性组合的港口集装箱吞吐量预测方法 总被引:1,自引:0,他引:1
张浩 《武汉理工大学学报(交通科学与工程版)》2007,31(2):373-376
以某港1981~1999年集装箱吞吐量为实测数据,建立其集装箱吞吐量的趋势外推、时间序列平滑、回归分析和灰色系统等预测模型.对比该港2000~2005年集装箱吞吐量各模型预测值与实际值的差异,分析了差异产生的原因及其单一预测模型的局限性,提出了基于最优线性组合的港口集装箱吞吐量预测法.以原各单项预测模型的预测值作为外生变量,以方差绝对值之加权和最小作为最优准则,建立线性组合预测模型,用单纯形表法解出加权系数,进行外推预测,并验证了方法的有效性. 相似文献
1000.
为提高门机使用的安全性,就M10-30型转柱式门座起重机(简称门机)超负荷(超载)限制器在使用中存在的问题进行分析,提出解决办法。阐述新型超负荷限制器的技术要求,详细介绍新型超负荷限制器的设计。通过设计、安装、调试、试用,充分证实了单片机和传感器技术在门机超负荷机构控制系统中的优越性。 相似文献