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901.
Jan A. Berg-Andereassen 《Maritime Policy and Management》2013,40(4):381-395
This paper tests two fundamental hypotheses concerning international maritime statistics. The first one deals with the question of stationary of the maritime market statistics. The second hypothesis tested is the assumption that the international maritime statistical time series are not distributed according to a normal of Guassian probability law, but rather belong to the same family of distributions with distinctly different critical parameters. Through well documented statistical methods, the paper concludes that the international freight rates observed on a day to day basis are generated by a random walk process. The paper finds that the shipping industry's conventioal wisdom is essentially correct. ‘Last done’ is as good a forecast of tomorrow's freight rate as any other generated by more sophisticated forecasting methods. Furthermore, freight rates and secondhand tonnage prices fluctuate closely together. The freight rates are generated by stochastic processes fully described by the Paretian family of distributions. The critical parameters of these distribution, the characteristic exponents, are such that the risk conscious ship operator can indeed reduce his exposure to risk by securing a correct set of freight rate contracts. 相似文献
902.
Travel time variability (i.e., random variations in travel time) leads to a travel time distribution for a repeated trip from a fixed origin to destination (e.g., from home to work). To represent travel time variability, a series of possible travel times per alternative (departure time, route or mode) are often used in stated choice experiments. In the traditional models, the probabilities associated with different travel scenarios (e.g., arriving early, on time and late) shown in the experiments are directly used as weights. However, evidence from psychology suggests that the shown probabilities may be transformed (underweighted or overweighted) by respondents. To account for this transformation of probabilities, this study incorporates perceptual conditioning through a non-linear probability weighting function into a utility maximisation framework, within which the empirical estimate of the value of expected travel time savings is estimated. The key advantage of this framework is that the estimated willingness to pay value can be directly linked to the source of utility (i.e., the probability distribution of travel time), while taking into account the perceptual transformation of probabilities. 相似文献
903.
Lynne Zeitlin Hale Mark Amaral Abdulrahman S. Issa B. A. J. Mwandotto 《Coastal management》2013,41(1):75-85
Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues. 相似文献
904.
E. G. Coombes A. P. Jones I. J. Bateman J. A. Tratalos J. A. Gill D. A. Showler 《Coastal management》2013,41(1):94-115
As tourists are sensitive to weather conditions and changes to the environments they visit, it is likely that climate change will affect coastal recreation in the future. To understand these impacts, it is first important to quantify how visitor numbers are associated with beach characteristics and weather patterns. Using the East Anglian coastline, UK, as a case study, information on the spatial distribution of visitors recorded from aircraft flights is combined with beach characteristic data in a Geographical Information System. In addition, surveys are undertaken at two beaches to assess temporal variations in visitation. The study finds a diverse range of characteristics are associated with visitor numbers. These findings are evaluated alongside the anticipated effects of climate change and management policies. Although it is predicted that warmer weather will increase visitor numbers overall, sea-level rise may reduce numbers at wide sandy beaches, which are currently most preferred by tourists. 相似文献
905.
Abstract The Sefton Coast Management Scheme in northwest England uses an area‐based project to achieve coordinated land management. It is founded on the ‘'Heritage Coast'’ model pioneered by the Countryside Commission where a ‘"Project Officer”; is employed to promote the Scheme and translate the aims into practical achievement. The Sefton Coast is described and a summary of British coastal planning policy precedes a detailed analysis of the Scheme. The Scheme is assessed with reference to practical management work, its success in competition for scarce financial resources, and the involvement of volunteers. It is established that the Project Officer is crucial to the success of the Scheme and that area‐based management can best be achieved through the local government planning process. Coastal planning needs now to be reviewed at national level to develop a policy for the whole coast using the experience of projects such as the Sefton Coast Management Scheme. 相似文献
906.
Chris A. Wold 《Coastal management》2013,41(2):213-230
Abstract This article explores the lack of uniform penalty assessment in the National Oceanic and Atmospheric Administration's (NOAA) civil penalty policy under the Fishery Conservation and Management Act (the Magnuson Act). The author sugests that NOAA's inconsistent penalty assessment invites noncompliance by fishers because they view the penalties as unfair and arbitrary. In particular, deterrence is undermined by the absence of a provision that removes the economic benefits of noncompliance. NOAA's policy is contrasted with the Environmental Protection Agency's (EPA) civil penalty policy, which uniformly assesses penalties while tailoring the penalty to the individual facts of the case and effectively removing the economic incentives of noncompliance. If NOAA implemented a policy similar to EPA's, NOAA would secure increased Magnuson Act compliance and higher penalty amounts. 相似文献
907.
908.
In this paper, a tramp ship routing model of fleet deployment in a hub-and-spoke network is presented. This model simultaneously determines the selection of hubs, the assignment of spokes to hubs, the deployment of feeder-containerships as well as containership routing between spokes and spokes, hubs and spokes, and hubs and hubs. Even though some parts have been studied, this complex combination of shipping problems has never been addressed. Because the problem is NP-hard, a genetic algorithm (GA) with local search is proposed. In the algorithm, a cut-off procedure is applied to fleet deployment in a sub-route strategy. A number of randomly generated problem instances are solved by both a mathematical program and the GA with local search. A simple but realistic heuristic algorithm is also developed. Both the GA with local search and the heuristic algorithm are used to solve a number of real case instances. A comparison of the results shows the efficiency of the GA with local search. The developed model can be used as a route-decision support tool for shipping companies that provide long-haul shipping services in a hub-and-spoke network. 相似文献
909.
James A. Fawcett 《Maritime Policy and Management》2013,40(7):753-765
The coast of East Africa, the Gulf of Aden and nearby waters of the Indian Ocean stand as the most pirate-ridden area of the seas at this time and naval forces from many nations have descended upon the region to ensure the safe passage of commercial vessels; yet piracy for ransom continues. The US, the North Atlantic Treaty Organization (NATO) and now the European Union deploy their navies to disrupt raids, intercept and capture pirates attacking ships passing through the region. However, apprehending pirates is only effective if they can also be brought to a court capable of adjudicating their guilt. Increasingly, the captured suspects are being disarmed and released, lacking a reliable nearby littoral state to prosecute them. In this region, with few viable states either willing or capable of holding piracy trials, apprehending pirates meets only part of the challenge of abating the practise. What is needed is a court system capable of adjudicating these cases; yet a thicket of both law and custom limits the ability of seagoing states to adequately arrest and hand over to reliable prosecution high seas pirates. This article addresses the problems inherent in abating piracy by these means off the coast of East Africa. 相似文献
910.
Abstract This paper investigates pedestrians' traffic gap acceptance for mid-block street crossing in urban areas. A field survey was carried out at an uncontrolled mid-block location in Athens, Greece. Pedestrians' decisions and traffic conditions were videotaped in terms of the size of traffic gaps rejected or accepted, waiting times and crossing attempts and vehicle speeds. A lognormal regression model was developed to examine pedestrian gap acceptance. It was found that gap acceptance was better explained by the distance from the incoming vehicle, rather than its speed. Other significant effects included illegal parking, presence of other pedestrians and incoming vehicles’ size. A binary logistic regression model was developed to examine the effect of traffic gaps and other parameters on pedestrians' decisions to cross the street or not. The results reveal that this decision is affected by the distance from the incoming vehicles and the waiting times of pedestrians. 相似文献