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121.
航运合约中的速遣费和滞期费对不定期船港口选择有重要影响.针对不定期船舶航速优化和港口选择问题,建立货主存在违约概率情况下不定期船港口选择停靠和航速优化模型,并考虑滞期费和速遣费对船公司利润的影响,使用改进型粒子群算法--两阶段粒子群算法进行求解模型.通过算例分析,将改进型粒子群算法与传统粒子群算法对比,发现改进型粒子群算法无论在收敛速度还是计算结果方面都优于传统粒子群算法.最后通过灵敏度分析发现,船公司利润在一定范围内会随着违约率、滞期费和港口装卸效率的上升而上升. 相似文献
122.
文章对船舶机械机座联接应用环氧树脂垫片进行了受力分析,给出了环氧树脂垫片总压应力计算和机座联接螺栓强度计算与校核方法,分析了机座联接螺栓在机械承受外力负荷时进行补充拧紧存在的安全危险,并提出了机座螺栓不宜在机械承受外力负荷时进行补偿拧紧的建议。 相似文献
123.
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
124.
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
125.
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
126.
Theo E. Notteboom Athanasios A. Pallis Peter W. De Langen Aimilia Papachristou 《Maritime Policy and Management》2013,40(7):636-653
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
127.
James P. Walsh 《Coastal management》2013,41(5):409-425
The Magnuson-Stevens Fishery Management and Conservation Act, enacted in 1974, is the primary federal fishery management legislation in the United States. The political impetus that led to enactment was the extensive foreign fish off U.S. shores that expanded following World War II and the failure of international negotiations to prevent the decline in many fisheries relied upon by domestic fishers. In Congress, there was uncertainty as to whether a comprehensive management program would be created along with a unilateral extension of fishery management jurisdiction out to 200 nautical miles. The delay in agreement over a new United Nations Law of the Sea Treaty and resolution of the extent of coastal nation jurisdiction over fisheries culminated in enactment of the legislation sponsored by Senator Warren Magnuson, a Democrat from Washington State, and Senator Ted Stevens, a Republican from the State of Alaska. 相似文献
128.
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
129.
Floriano Pires 《Maritime Policy and Management》2013,40(7):831-844
ABSTRACTThe 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
130.
ABSTRACTWe 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