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271.
非理性投资行为是导致航运危机的重要原因,也是航运企业可持续发展的关键障碍.基于行为金融学理论,分析组织因素、环境因素、个人因素与航运企业非理性投资行为间的关系,并构建非理性投资行为影响因素的结构方程模型.实证结果显示:问责制度、激励措施、项目熟悉度和经验水平对非理性投资行为具有显著的负向影响;运价走势和竞争压力对非理性投资行为具有显著的正向影响;非理性投资行为会导致航运企业投资风险增加,投资绩效降低.  相似文献   
272.
中国国际海运船队温室气体排放测算研究   总被引:1,自引:0,他引:1  
为估算中国国际海运船队温室气体的排放状况,对联合国政府间气候变化专门委员会(IPCC)提出的“自下而上”以及“自上而下”排放量估测方法进行分析,表明海运温室气体排放量取决于海运业燃油消耗量以及燃油的排放因子,燃油消耗量与海运船舶的活动频率以及船舶能效有关。提出基于船舶装机总量以及基于船舶活动强度的两种估算方法。结果表明,1990~2007年间,中国国际海运船队二氧化碳排放量平均年递增7.6%,而同期全球国际海运温室气体排放平均年递增3.7%。中国应积极研究相关措施以控制中国国际海运船队二氧化碳排放量的不断增长。  相似文献   
273.
姜宁林 《水运工程》2013,(8):131-135
利用长江口澄通河段多年实测水深、流量等资料,建立反映澄通河段典型断面面积随含沙量和落潮流量变化的河相关系。依据所建立的各典型断面的河相关系式,分别探讨在含沙量变化和落潮流量变化下,典型断面面积的变化情况。分析可知,当含沙量从0.312 kg/m3减少到0.043 kg/m3时,各典型断面的面积普遍增加超过55%,而当落潮流量从10000 m3/s增加到100000 m3/s时,典型断面面积增加了约7.7倍。这表明在落潮流量不变的前提下,含沙量的减少会导致澄通河段各典型断面面积较大幅度地增大,而在含沙量保持不变的情况下,随着落潮流量的增加,断面面积的增加也较为明显。  相似文献   
274.
Shipping business is capital intensive and highly competitive. It necessitates for the shipping companies to constantly monitor their performance and measure relative efficiencies of their supply chains. Despite such importance, the studies devoted to this field have been surprisingly limited. This paper reviews the involved factors and proposes a relational network data envelopment analysis (DEA) model for measuring the efficiency of supply chain of an international shipping company in Iran with relevant sub-processes in the period 2008–2011. First, the supply chain network of the company is illustrated and then the input and output variables associated to each member are determined. The proposed model is suitable for shipping companies which usually use similar pattern in this business. Finally based on the results, recommendations are made for improvements and a new field of business is also proposed.  相似文献   
275.
Port economics, management and policy have progressively emerged as a distinctive research field, and a core part of maritime economics. This paper provides an analysis of all the 267 port studies published in Maritime Policy & Management (MPM) since its inception in 1973. This paper provides a content analysis for seven interrelated research theme categories including main research topics and methods, authorship distribution and citation counts. It is demonstrated that MPM played, and continues to play, a key role in publishing research on seaports. The published research increasingly applies established analytical frameworks to ports. The paper concludes with a discussion on current challenges for port-related research.  相似文献   
276.
唐晓峰 《水运工程》2013,(4):187-191
新浏河沙护滩及南沙头通道潜堤工程是长江口深水航道治理工程的重要组成部分.受不利河势变化影响,其整治建筑物局部余排外侧冲刷持续发展,影响了结构的安全稳定.为确保治理效果而实施了本次防护工程.在总结长江口深水航道治理工程经验的基础上,通过对现场水流条件分析及典型施工,在船机设备、软体排加工及施工工艺等方面进行了一系列优化改进,首次在长江口水深30m以上的深水区成功实施了砂袋抛填及软体排铺设,满足了设计要求.  相似文献   
277.
基于有限体积方法,建立平面二维水流数学模型,对北江白石窑枢纽坝下19km航道整治工程进行数值研究.运用实测水文资料对模型进行验证.验证结果表明:该模型精度符合规范要求.计算了整治工程实施前、后白石窑坝下游河段通航水流特性,分析了各级恒定流和非恒定流作用下整治工程对坝下游河段通航水流条件的影响.研究结果表明:实施整治工程后,整治河段水流条件得到了明显的改善,水流条件可以满足千吨级船舶的通航要求.  相似文献   
278.
Maritime trade has been and even continues to account for about a lion's share of India's total cargo volumes. Despite the growth of multimodal transport (by land, water and air), shipping still continues to be the major mode of transport in the bulk carriage of country's overseas trade. In view of this vital role of shipping, in the first four decades of independence, under the initiative of planned development and active government support, India's shipping and port sector saw dramatic growth in their performance to build adequate national fleet, in keeping up with the transport of overseas cargo. However, the onset of economic liberalization in 1991 has given rise to many new dimensions in the development of the shipping and port sector of the country with a significant redefinition of shipping and port services, in response to the new global trend patterns. For instance, it has also established the new era of containerization in the mode of cargo delivery from the dominance of the era of bulk and break-bulk trade during the decade of sixties and seventies. Moreover, as global competition increases, in response to this emerging trade patterns within this country, India's volume of traffic growth also increases manifold. So, India's shipping and port sectors need, significantly, to build up and furnish their capacity by increasing the frequency of this mode of transport i.e. the growth of the national overseas fleet to meet this surging demand. This paper, therefore, have focused on this role of shipping in such rising overseas trade, with a view to examine the shipping performance (the growth of overseas fleet) in response to the growing overseas trade at all ports of India during the period (1999–2000 to 2008–2009), in terms of both a mathematical model and a graphical representation. Finally, it concludes that the absolute overseas trade, being highly import dependent, have led to a more or less stagnant performance in overseas shipping, owing to the lack of the adequate growth of absolute overseas exports during this period.  相似文献   
279.
ABSTRACT

The literature on valuation of time charter contracts and real options in shipping generally relies on the complete markets hypothesis and the risk-neutrality of agents. However, these assumptions fail completely in some shipping market segments. This study proposes a numerical approach—based on discounting the certainty equivalent payoff at the risk-free rate—which incorporates the agent’s risk preferences through an exponential utility function. The method comprises an iterative Monte Carlo nested simulation with the real probability measure. This method is applied to a case of Suezmax tankers. The stochastic evolution of the time charter rates is modelled as a geometric mean-reverting process. The case study supports the applicability of the proposed method and evidences that the effect of risk preference may be significant, mainly for more risk-averse agents. Although the method involves intensive computation, it has the benefits of theoretical ease and flexibility, which could encourage utilisation by practitioners.  相似文献   
280.
ABSTRACT

We provide two empirical models for calculating the sailing time and berth time of maritime container liner networks to effectively model the ambiguity associated with sea and port contingency for ex-ante decisions of fleet deployment and route planning. The models are based on recorded AIS data of 110 mega vessels including all the operating container mega vessels with a capacity of 16,000 TEU or more during the summer of 2015. The models are able to estimate the sailing time (with R2 of 0.974) and the berth time (with R2 of 0.895) without knowledge of any operational-level explanatory variables. The models are validated against the published East Asia–North Europe services. Moreover, the study reveals that vessel operators adopt different berthing and sailing strategies even under the same conditions.  相似文献   
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