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991.
This paper seeks to explore the relationship between mode and destination choice in an integrated nested choice model. A fundamental
argument can be made that in certain circumstances, the ordering of choices should be reversed from the usual sequence of
destination choice preceding mode choice. This results in a travel demand model where travelers are more likely to change
destinations than to change transportation modes. For small and medium size urban areas, particularly in the United States,
with less well developed public transit systems that draw few choice riders, this assumption makes much more sense than the
traditional modeling assumptions. The models used in the new travel modeling system developed for Knoxville, Tennessee utilize
this reversed ordering, with generally good results, which required no external tinkering in the logsum parameters. 相似文献
992.
This paper proposes a new activity-based transit assignment model for investigating the scheduling (or timetabling) problem
of transit services in multi-modal transit networks. The proposed model can be used to generate the short-term and long-term
timetables of multimodal transit lines for transit operations and service planning purposes. The interaction between transit
timetables and passenger activity-travel scheduling behaviors is captured by the proposed model, as the activity and travel
choices of transit passengers are considered explicitly in terms of departure time choice, activity/trip chain choices, activity
duration choice, transit line and mode choices. A heuristic solution algorithm which combines the Hooke–Jeeves method and
an iterative supply–demand equilibrium approach is developed to solve the proposed model. Two numerical examples are presented
to illustrate the differences between the activity-based approach and the traditional trip-based method, together with comparison
on the effects of optimal timetables with even and uneven headways. It is shown that the passenger travel scheduling pattern
derived from the activity-based approach is significantly different from that obtained by the trip-based method, and that
a demand-sensitive (with uneven headway) timetable is more efficient than an even-headway timetable. 相似文献
993.
In this paper we review freight forecasting models and current advances and needs with respect to data and model development.
We then present a case study to suggest which models should be developed for the State of California in the US. We suggest
several alternatives including an aggregate commodity flow model, a disaggregate regional logistics model and a hybrid regional
logistics model with a truck touring model. We point out however, that the data requirements for the latter model would be
extensive. In addition, the development of hybrid models, for example progress in the integration of regional logistics models
with urban truck touring models, will introduce new problems such as reconciling the outputs of multiple models for consistency. 相似文献
994.
A new model system dealing with trips of length up to 100 km has recently been developed in Norway. A new way of dealing with
seasonal passes for public transport is used in the travel-to-work model. The objective was to account for the fact that a
respondent that posses a seasonal pass for public transport may behave as if public transport is free on the day they report
a travel diary. On the other hand, we can not assume that public transport is free for respondents that used other modes of
transport or that public transport is free to alternative destinations. This problem was solved by defining seasonal pass
as a separate alternative in the form of a nest that included all modes of travel. The cost of a seasonal pass is a common
cost for all modes in the nest and will thus not affect the choice within the nest. The estimation of this specification is
compared with the more common approach of assigning an average cost per day based on the cost of a monthly pass and the number
of workdays in a month. The comparison indicates that the “average cost per day” approach may produce biased estimates for
several parameters. It also turns out that the cost parameter for seasonal pass is higher than the parameter for “out of pocket”
cost, probably reflecting that there will be some uncertainty with respect to the actual use of a seasonal pass. 相似文献
995.
Nazneen Ferdous Abdul Rawoof Pinjari Chandra R. Bhat Ram M. Pendyala 《Transportation》2010,37(3):363-390
This paper proposes a multiple discrete continuous nested extreme value (MDCNEV) model to analyze household expenditures for
transportation-related items in relation to a host of other consumption categories. The model system presented in this paper
is capable of providing a comprehensive assessment of how household consumption patterns (including savings) would be impacted
by increases in fuel prices or any other household expense. The MDCNEV model presented in this paper is estimated on disaggregate
consumption data from the 2002 Consumer Expenditure Survey data of the United States. Model estimation results show that a
host of household and personal socio-economic, demographic, and location variables affect the proportion of monetary resources
that households allocate to various consumption categories. Sensitivity analysis conducted using the model demonstrates the
applicability of the model for quantifying consumption adjustment patterns in response to rising fuel prices. It is found
that households adjust their food consumption, vehicular purchases, and savings rates in the short run. In the long term,
adjustments are also made to housing choices (expenses), calling for the need to ensure that fuel price effects are adequately
reflected in integrated microsimulation models of land use and travel. 相似文献
996.
997.
城市轨道交通的建设理念及其实现 总被引:3,自引:2,他引:1
从工程实践出发,结合城市轨道交通的建设标准和规范,通过规划选址、资源整合共享、设计体现等三个视角, 总结归纳出了城市轨道交通在规划、设计、建设中普遍遵循的一些理念,并对这些理念的实现做了初步探讨,从规划、细节设计等方面提出落实相应理念的建议。 相似文献
998.
999.
1000.
根据杭州地铁物业开发建设的原则,结合杭州地铁1号线3个车站周边物业开发的情况,介绍了地铁车站与周边地块物业开发衔接的几种形式,并对车站出入口及风亭等与物业的开发进行了分析。 相似文献