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101.
Abstract

This article applies a methodology for selecting carriers for the transportation of dangerous goods by road, with a special focus on risk management aspects. The methodology makes use of Stated Preference techniques and verifies the most critical risk-related variables influencing decision-making from the shippers' point of view. It embraces the planning and execution stages, an evaluation of the contracted company and a feedback process. The methodology was effectively applied to the case of liquid fuel shippers in the Brazilian middle-west region where it proved possible to identify which dangerous goods road transport company to contract in accordance with the risk management factors selected by the decision makers.  相似文献   
102.
Abstract

This paper computes the cost of traffic congestion in the city of Antofagasta in Chile. A microsimulation is implemented where all the agents of the system travel across the transport network. The congestion cost is computed through the aggregation of the opportunity cost of people waiting within the transport system, as a consequence of traffic congestion. Monte Carlo experiments produced an approximated congestion cost of US$1.02 million during a typical working day. Moreover, the simulation provides useful information about the average traveling time for the 14 districts of the city.  相似文献   
103.
Abstract

Public transport policy in the Madrid Metropolitan Area is often deemed as a success. In 1985, an important reform was carried out in order to create a new administrative authority to coordinate all public transport modes and establish a single fare for all of them. This reform prompted a huge growth in public transport usage, even though it reduced the funding coverage ratio of the transport system. Since then, Madrid’s public transport system has been undergoing an increasing level of subsidization, which might jeopardize the financial viability of the city public transport system in the future. In this paper, we present a detailed analysis of the evolution of the public transport funding policy in Madrid in recent years. We found that the increasing level of subsidy can hardly be explained on the basis of equity issues. Moreover, we claim that there is still room for a funding policy that makes the efficiency of the system compatible with its financial sustainability.  相似文献   
104.
Abstract

This paper develops a heuristic algorithm for the allocation of airport runway capacity to minimise the cost of arrival and departure aircraft/flight delays. The algorithm is developed as a potential alternative to optimisation models based on linear and integer programming. The algorithm is based on heuristic (‘greedy’) criteria that closely reflect the ‘rules of thumb’ used by air traffic controllers. Using inputs such as arrival and departure demand, airport runway system capacity envelopes and cost of aircraft/flight delays, the main output minimises the cost of arrival and departure delays as well as the corresponding interdependent airport runway system arrival and departure capacity allocation. The algorithm is applied to traffic scenarios at three busy US airports. The results are used to validate the performance of the proposed heuristic algorithm against results from selected benchmarking optimisation models.  相似文献   
105.
An empirical algorithm has been developed to compute the sea surface CO2 fugacity (fCO2sw) in the Bay of Biscay from remotely sensed sea surface temperature (SSTRS) and chlorophyll a (chl aRS) retrieved from AVHRR and SeaWiFS sensors, respectively. Underway fCO2sw measurements recorded during 2003 were correlated with SSTRS and chl aRS data yielding a regression error of 0.1 ± 7.5 µatm (mean ± standard deviation). The spatial and temporal variability of air–sea fCO2 gradient (ΔfCO2) and air–sea CO2 flux (FCO2) was analyzed using remotely sensed images from September 1997 to December 2004. An average FCO2 of ? 1.9 ± 0.1 mol m? 2 yr? 1 characterized the Bay of Biscay as a CO2 sink that is suffering a significant long-term decrease of 0.08 ± 0.05 mol m? 2 yr? 2 in its capacity to store atmospheric CO2. The main parameter controlling the long-term variability of the CO2 uptake from the atmosphere was the air–sea CO2 transfer velocity (57%), followed by the SSTRS (10%) and the chl aRS (2%).  相似文献   
106.
In recent years in the European Union (EU), we have witnessed an externalization process of the provision of local government services, in order to separate the political responsibility and the direct delivery of the service. The reasons that justify this process are focused on the belief that the private sector is more efficient in carrying out economic activities, the pressure to reduce the public deficit and the public debt, the search for management systems that bypass public administration procedures, and the increase of control on local governments in auditing and accountability issues.The objective of this paper is to compare the efficiency of public and private sectors in the provision of urban transportation services. This paper shows the results of an empirical study commissioned by the Regional Audit Office of Catalonia (Spain), in order to evaluate the efficiency with which urban transportation services are delivered in the most important cities of this region. This efficiency study has been carried out using the Data Envelopment Analysis (DEA) model, multiple linear regression and logit and cluster analysis. The results allow us to conclude that, in the cities studied, exogenous factors are not relevant and the private management of urban transport service is not more efficient than public management.  相似文献   
107.
The Paris Memorandum of Understanding (Paris MoU) has defined criteria aimed at better targeting of ships for Port State Control inspections. These criteria are mostly based on ship detentions or deficiencies. Another approach proposed in this paper is based on the concept of risk, combining in various ways the probability of the occurrence of casualties and the potential consequences of such occurrences. These measures are to help identify High Risk Vessels (HRV) and to inspect them accordingly.  相似文献   
108.
During the 1990s Argentina engaged in a process of restructuring and deregulation of its ports. The main objective of the reform was to increase efficiency and service quality and to reduce the size and role of the public sector in ports. Overall, it was expected to allow the transport sector to adjust its capacity to demand changes and to facilitate international trade while contributing to the reduction of the fiscal burden of this sector. This paper shows that the reform caused significant efficiency gains, allowing a 50% drop in container terminal handling price within five years in the most important ports. The paper also identifies outstanding issues that could impact the long-run sustainability of the gains achieved. Among these issues, emphasis is given to recent horizontal and vertical mergers in the Port of Buenos Aires and their consequences in terms of actual competition and access regulation.  相似文献   
109.
The authors present a recent development in the use of classic travel demand models (TDMs) to environmental impact assessment of transport, far from its initial target. By comparing previous cases found in the literature (Chester, Seoul, Florence, Brisbane and Saint-Etienne) with their present works (Eval-PDU in Nantes), the authors notice that their predecessors tend to be evasive on their use of TDM. Hence, traffic data are little discussed in these works, while their works constitute one of the main stakes in this kind of study. Indeed, the hypotheses for traffic modeling are impacting the next steps of the modeling chain (pollutants emission/dispersion). The importance of this first modeling stage implies that relevant attention has to be brought to their assumptions and input data.  相似文献   
110.
This study aims to determine risk factors contributing to traffic crashes in 9,176 fatal cases involving motorcycle in Malaysia between 2010 and 2012. For this purpose, both multinomial and mixed models of motorcycle fatal crash outcome based on the number of vehicle involved are estimated. The corresponding model predicts the probability of three fatal crash outcomes: motorcycle single-vehicle fatal crash, motorcycle fatal crash involving another vehicle and motorcycle fatal crash involving two or more vehicles. Several road characteristic and environmental factors are considered including type of road in the hierarchy, location, road geometry, posted speed limit, road marking type, lighting, time of day and weather conditions during the fatal crash. The estimation results suggest that curve road sections, no road marking, smooth, rut and corrugation of road surface and wee hours, i.e. between 00.00 am to 6 am, increase the probability of motorcycle single-vehicle fatal crashes. As for the motorcycle fatal crashes involving multiple vehicles, factors such as expressway, primary and secondary roads, speed limit more than 70 km/h, roads with non-permissible marking, i.e. double lane line and daylight condition are found to cause an increase the probability of their occurrence. The estimation results also suggest that time of day (between 7 pm to 12 pm) has an increasing impact on the probability of motorcycle single-vehicle fatal crashes and motorcycle fatal crashes involving two or more vehicles. Whilst the multinomial logit model was found as more parsimonious, the mixed logit model is likely to capture the unobserved heterogeneity in fatal motorcycle crashes based on the number of vehicles involved due to the underreporting data with two random effect parameters including 70 km/h speed limit and double lane line road marking.  相似文献   
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