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171.
Given the inherent complexity of the maritime transportation system, developing effective policy can be challenging. Using risk factors identified by an elicitation and aggregation of expert judgment, a relative-risk rating scheme was developed in the theory-building tradition of the social sciences. The model was empirically evaluated using 18 months of data from the US small passenger vessel sector. The model identified that the top 10% of relatively highest risk vessels accounted for 50% of all marine casualties during the period of examination. A policy for deploying the model nationally is proposed.  相似文献   
172.
Port choice is an important issue to be investigated to ensure the effective integration of container supply chains and the sustainable development of regional economy. The selection of appropriate ports to facilitate shipping activities and international trade is crucial for many stakeholders, including shipping lines, port administrators, cargo shippers and national governments. The task is essentially a process of multiple criterion decision-making (MCDM) under uncertainty, requiring analysts to derive rational decisions from uncertain and incomplete data related to different quantitative and qualitative determinants. This paper aims at proposing a new conceptual port choice method by explaining the role fuzzy logic in evidential reasoning in a complementary way, in which various forms of raw data (either objective or subjective) collected to evaluate port performance can first be converted into and presented as fuzzy grades defined using linguistics terms with degrees of belief (DoBs) and second be combined using evidential reasoning to produce a port choice preference score. The method is applied to analyse the selection of major Northeast Asian (NEA) container ports from a shipping line’s perspective. The outcome, a port choice preference score, is calculated using evidential reasoning to directly synthesize the true estimation of the port with respect to each criterion and therefore, unlike a relative ranking index, keeps the ‘goodness’ of port evaluation, capable of benchmarking a specific port’s performance and monitoring the increase of its competitiveness in a longitude study with respect to an individual criterion or all the criteria as a whole.  相似文献   
173.
共用车汽车租赁已经吸引了数以万计的城市青年加入拼车一族.如今,这场运动正在成为当下汽车消费的主流--就连赫兹租车和福特汽车也想参与其中.  相似文献   
174.
The US federal Congestion Mitigation and Air Quality program was created to fund transportation projects that have the potential to contribute to the attainment or maintenance of the National Ambient Air Quality Standards. This study evaluates a random sample of eight suburban bicycle and pedestrian facilities funded by the Congestion Mitigation and Air Quality Program in the Chicago metro area. Users of these facilities were randomly sampled using a “time-based” user sampling approach and surveyed in intercept mode to implement a recall-based evaluation design. A random intercept logit model was used to explain variations in the propensity to switch from single occupant vehicle use to bicycling or walking, using attributes of users and sites. The analysis shows relatively low usage levels but that substitution of motorized modes have resulted, potentially leading to improved air quality outcomes.  相似文献   
175.

In this article, an "intelligent" airline seat inventory control system is developed. Applications of the system are considered for both nonstop flights and flights with stopovers. The system developed is able to recognize a situation characterized by the number of reservations made by individual passenger classes and the number of canceled reservations at a certain moment in time before departure. The system can also make the appropriate decision without knowing the functional relationships in effect between individual variables. As in other intelligent systems, the "intelligent" airline seat inventory control system proposed here is able to generalize, adapt and learn based on new knowledge and new information. The "intelligent" airline seat inventory control system is based on fuzzy logic. The system makes on-line decisions as to whether to accept or reject any passenger request using established fuzzy rules. The "intelligent" system's results are compared with those of the EMSR model for nonstop flights. The results for flights with stopovers are compared with those obtained using integer programming. The final conclusions are very promising.  相似文献   
176.
Abstract

This paper explores the external costs of domestic container transportation in Taiwan by analysing the origin and destination of current container cargoes. After reviewing an extensive literature survey of methods of external cost, a comparison of external costs between trucking and short sea shipping (SSS) by corridor is made by using a model developed in this paper. Based on the findings that external costs of SSS are considerably lower than truck transport and can be a viable alternative to current domestic container cargo transportation, we discuss the significance and managerial implications of SSS from the perspective of green logistics. In so doing, a top‐down approach is employed for developing government policies, which aim to not only reduce the external costs of domestic container transportation but also promote SSS in Taiwan.  相似文献   
177.
Accurate measurement of travel behaviour is vital for transport planning, modelling, public health epidemiology, and assessing the impact of travel interventions. Self-reported diaries and questionnaires are traditionally used as measurement tools; advances in Global Positioning Systems (GPS) technology allow for comparison. This review aimed to identify and report about studies comparing self-reported and GPS-measured journey durations. We systematically searched, appraised, and analysed published and unpublished articles from electronic databases, reference lists, bibliographies, and websites up to December 2012. Included studies used GPS and self-report to investigate trip duration. The average trip duration from each measure was compared and an aggregated, pooled estimate of the difference, weighted by number of trips, was calculated. We found 12 results from eight eligible studies. All studies showed self-reported journey times were greater than GPS-measured times. The difference between self-report and GPS times ranged from over-reporting of +2.2 to +13.5 minutes per journey. The aggregated, pooled estimate of the difference, weighted by number of trips, was over-report of +4.4 minutes (+28.6%). Studies comparing self-reported and GPS-measured journey duration have shown self-reported to be consistently over-reported across the study sample. Our findings suggest that when using self-reported journey behaviour, the journey durations should be treated as an over-estimation.  相似文献   
178.
179.
介绍了一种装置,它采用8031单片机技术,实现了内燃机车与机车运行速度有关的五项功能的集中控制,给出了系统的框图和部分关键电路的实现方法。实践证明装置运用情况良好。  相似文献   
180.
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