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621.
Some scholars consider that today’s market conditions are in favor of the Northern Sea Route (NSR) rather than the Suez Canal Route (SCR). However, the number of bulk carriers using the NSR remains extremely limited, despite higher fuel prices since 2009 and subsequent significant fuel savings. In 2013, there were 53 transits via the Arctic, out of which 27 by oil tankers and 6 by bulk carriers. In this article we show that this result might be attributable to a factor, which is not considered in most studies: the spot freight rate to fuel ratio which governs ship owners’ decisions regarding the sailing speed. Due to a low ratio since 2011, the speed of vessels on the SCR is at its lowest level, and potential NSR fuel savings are too limited to provide a viable alternative. We further argue that, contrary to most studies, internalizing NSR environmental benefits marginally improves the attractiveness of the NSR.  相似文献   
622.
According to a range of assessments, there exists a large cost-effective potential to increase energy efficiency in shipping through reduced speed at sea enabled by shorter time in port. This means that the energy needed can be reduced whilst maintaining the same transport service. However, the fact that a large cost-effective potential has been identified that is not being harnessed by decision-makers in practice suggests that there is more to this potential to understand. In this paper, the possibilities for increasing energy efficiency by reducing waiting time in port are explored and problematised through a case study of a short sea bulk shipping company transporting dry bulk goods mainly in the North and Baltic seas. Operational data from two ships in the company’s fleet for one year showed that the ships spent more than 40% of their time in ports and that half of the time in port was not productive. The two most important reasons for the large share of unproductive time were that ports were closed on nights and weekends and that ships arrived too early before the stevedores were ready to load or unload the cargo. Reducing all of the unproductive time may be difficult, but the results also show that even a conservative estimate of one to four hours of reduced time per port call would lead to a reduction in energy use of 2–8%. From in-depth interviews with employees of the shipping company, ports and ship agencies, a complex picture is painted when attempting to understand how this potential arises. Aspects such as a lack of effective ship-shore-port communication, little time for ship operators, an absence of means for accurately predicting energy use of voyages as a function of speed, perceived risk of arriving too late, and relationships with third-party technical management may all play a role.  相似文献   
623.
In this paper, the maritime fleet renewal problem (MFRP) is extended to include regional limitations in the form of emission control areas. The motivation for including this aspect is that strengthening of emission regulations in such areas is expected to be challenging for deep sea shipping in the years to come. In the proposed model, various means to cope with these stricter emission regulations are evaluated for new vessels, and the possibility of upgrading existing vessels with new emission reduction technology is introduced. We consider future fuel prices to be important for the problem, and have chosen to treat them as uncertain, and thus, a stochastic programming model is chosen. A fleet renewal problem faced by the liner shipping operator Wallenius Wilhelmsen Logistics, concerning whether to use low sulphur fuel or have an exhaust gas scrubber system installed to comply with sulphur regulation in emission control areas from 2015, is used as a case study. Furthermore, tests show that the savings from including the aspect of emission control areas in the MFRP are substantial.  相似文献   
624.
With the effects of global warming, the Arctic is presenting a new environment where numerous ice floes are floating on the open sea surface. Whilst this has improved Arctic shipping navigability in an unprecedented way, the interaction of such floes with ships is yet to be understood to aid the designing of ships and route planning for this region. To further explore this topic, the present work develops a procedure to derive an empirical equation that can predict the effects of such floes on ship resistance. Based on a validated computational approach, extensive data are extracted from simulations of three different ships with varying operational and environmental conditions. The ice-floe resistance is shown to strongly correlate with ship beam, ship buttock angle, ship waterline angle, ship speed, ice concentration, ice thickness and floe diameter, and the regression powers of each of the parameters on resistance are ascertained. This leads to a generic empirical equation that can swiftly predict ice-floe resistance for a given ship in a given condition. Subsequently, demonstrations are given on the incorporation of the derived equation into a set of real-time Arctic ship performance model and voyage planning tool, which can predict a ship's fuel consumption in ice-infested seas and dynamically suggest a route with the least safety concern and fuel consumption. Moreover, the equation is validated by providing ice resistance prediction for experimental and full-scale conditions from multiple sources, showing high accuracy. In conclusion, the empirical equation is shown to give valid and rapid estimates for ice-floe resistance, providing valuable insights into ship designs for the region, as well as facilitating practical applications for polar navigation.  相似文献   
625.
This paper proposes a state-augmented shipping (SAS) network framework to integrate various activities in liner container shipping chain, including container loading/unloading, transshipment, dwelling at visited ports, in-transit waiting and in-sea transport process. Based on the SAS network framework, we develop a chance-constrained optimization model for a joint cargo assignment problem. The model attempts to maximize the carrier’s profit by simultaneously determining optimal ship fleet capacity setting, ship route schedules and cargo allocation scheme. With a few disparities from previous studies, we take into account two differentiated container demands: deterministic contracted basis demand received from large manufacturers and uncertain spot demand collected from the spot market. The economies of scale of ship size are incorporated to examine the scaling effect of ship capacity setting in the cargo assignment problem. Meanwhile, the schedule coordination strategy is introduced to measure the in-transit waiting time and resultant storage cost. Through two numerical studies, it is demonstrated that the proposed chance-constrained joint optimization model can characterize the impact of carrier’s risk preference on decisions of the container cargo assignment. Moreover, considering the scaling effect of large ships can alleviate the concern of cargo overload rejection and consequently help carriers make more promising ship deployment schemes.  相似文献   
626.
The foreign trade transport accessibility (FTTA) of Mainland China to overseas regions is studied in terms of the shipping connectivity and achievable market scales. First, the concept of FTTA is defined. Second, the path choice behavior of shippers is analyzed, and a method to measure FTTA is proposed. Last, with 357 cities in Mainland China as the origins and eight overseas regions as the destinations, the FTTAs from origins to destinations are evaluated. The study is helpful to acquaint decision-makers with the FTTA’s spatial distribution and to offer information by which China can expand its export-oriented industry and optimize its port and shipping industries.  相似文献   
627.
Container liner shipping companies only partially alter their shipping networks to cope with the changing demand, rather than entirely redesign and change the network. In view of the practice, this paper proposes an optimal container liner shipping network alteration problem based on an interesting idea of segment, which is a sequence of legs from a head port to a tail port that are visited by the same type of ship more than once in the existing shipping network. In segment-based network alteration, the segments are intact and each port is visited by the same type of ship and from the same previous ports. As a result, the designed network needs minimum modification before implementation. A mixed-integer linear programming model with a polynomial number of variables is developed for the proposed segmented-based liner shipping network alternation problem. The developed model is applied to an Asia–Europe–Oceania liner shipping network with a total of 46 ports and 11 ship routes. Results demonstrate that the problem could be solved efficiently and the optimized network reduces the total cost of the initial network considerably.  相似文献   
628.
This paper deals with a practical tramp ship routing problem while taking into account different bunker prices at different ports, which is called the joint tramp ship routing and bunkering (JSRB) problem. Given a set of cargoes to be transported and a set of ports with different bunker prices, the proposed problem determines how to route ships to carry the cargoes and the amount of bunker to purchase at each port, in order to maximize the total profit. After building an integer linear programming model for the JSRB problem, we propose a tailored branch-and-price (B&P) solution approach. The B&P approach incorporates an efficient method for obtaining the optimal bunkering policy and a novel dominance rule for detecting inefficient routing options. The B&P approach is tested with randomly generated large-scale instances derived from real-world planning problems. All of the instances can be solved efficiently. Moreover, the proposed approach for the JSRB problem outperforms the conventional sequential planning approach and can incorporate the prediction of future cargo demand to avoid making myopic decisions.  相似文献   
629.
随着我国参与经济全球化的长足发展,省域内临港经济区内的跨文化交流日益频繁,同时跨文化适应问题也越发突显,并以前所未有的速度影响着港口航运物流企业人员的工作表现。通过采用SPSS软件和Microsoft Excel软件对调查数据进行的统计分析,发现相关企业人员的跨文化适应情况与工作表现呈现正相关关系。通过进一步分析发现影响这些人员的跨文化适应的社会文化和心理因素表现出共性特征。这为临港经济相关专业"专业英语"教学改革提供了依据。  相似文献   
630.
A wide array of technical and operational solutions is available to shipowners in order to comply with existing and upcoming environmental regulation within Emission Control Areas (ECAs). Liquefied Natural Gas (LNG) is a promising alternative since it offers potential cost savings in addition to ensuring compliance with ECA regulation. But investment to retrofit existing vessels to be able to use LNG carries significant upfront costs, and a high degree of uncertainty remains on the differential between the prices of LNG and conventional maritime fuels, as well as on the availability of LNG and the reliability of its supply chain. New technologies such as LNG inherently carry substantial risk and an ill-chosen investment strategy may have irreversible consequences that could jeopardise the future of the shipping company. One important question is whether interested owners should invest in LNG now to comply with ECA rules in 2015 and reap the benefits of lower LNG prices, or whether it would be advisable to wait until some of the uncertainty is resolved.While traditional discounted cash flow techniques are unable to account for the value of managerial flexibility linked, for example, to the possibility of deferring an investment, real option analysis can be used to analyse such cases. The paper discusses the optimal time for investment in LNG retrofit and takes specific account of the value of an investment deferral strategy versus the advantages obtainable from the immediate exploitation of fuel price differentials. Through the use of a real option model the paper shows that there is a trade-off between low fuel prices and capital expenses for investment in LNG retrofit. The development in LNG is critically dependent on its future price as well as the reduction in capital costs and ship retrofitting costs. In this respect, policy makers can play a critical role in providing support to advance technical knowledge, maintain LNG prices at favourable levels and in avoiding ambiguity on regulation.  相似文献   
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