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31.
This paper presents the results of a major before-and-after study carried out to establish the short term effects of the removal of a severe bottleneck in the road network around Amsterdam. An important focus in the study was on measuring changes in the timing of travel, as well as changes in route choice, mode choice, destination choice and frequency of travel. The results of the study indicated that, in the short run, there was little or no change in mode choice, nor was there significant emergence of new induced trips. On the other hand, large shifts in time of travel as well as route choice were reported, emphasising the importance of alterations to the timing and routes of existing trips when congestion is relieved, and the need to consider the benefits these bring in evaluating the impact of any road investment.  相似文献   
32.
经济状况和未来的排放要求可能对这两个品牌不利,塔塔应为此做好准备,并具有足够的资本,才能安全渡过这场经济风暴。  相似文献   
33.
This article examines the use of inland mined sand and offshore dredged sand for beach nourishment projects in North Carolina, focusing on the question of whether inland mined sand is economically preferential for hot‐spot erosion control. Excavation, processing, and transport costs are presented, and cost efficiencies of hypothetical beach nourishment projects are compared. Cost analyses indicate that inland mined sand is economical for small projects (10,000–50,000 cubic yards), given that a clean sand source can be located within 15 miles of the nourishment site. The two factors primarily influencing per cubic yard costs of inland sand are overland transportation expenses and processing costs. The use of dredged offshore sand is less expensive for large projects (> 100,000 cubic yards) due to the economies of scale affecting dredge mobilization. Large beach nourishment projects in North Carolina will most likely continue to utilize offshore dredged sand.  相似文献   
34.
There is growing interest in the use of models that recognise the role of individuals’ attitudes and perceptions in choice behaviour. Rather than relying on simple linear approaches or a potentially bias-inducing deterministic approach based on incorporating stated attitudinal indicators directly in the choice model, researchers have recently recognised the latent nature of attitudes. The uptake of such latent attitude models in applied work has however been slow, while a number of overly simplistic assumptions are also commonly made. In this article, we present an application of jointly estimated attitudinal and choice models to a real-world transport study, looking at the role of latent attitudes in a rail travel context. Our results show the impact that concern with privacy, liberty and security, and distrust of business, technology and authority have on the desire for rail travel in the face of increased security measures, as well as for universal security checks. Alongside demonstrating the applicability of the model in applied work, we also address a number of theoretical issues. We first show the equivalence of two different normalisations discussed in the literature. Unlike many other latent attitude studies, we explicitly recognise the repeated choice nature of the data. Finally, the main methodological contribution comes in replacing the typically used continuous model for attitudinal response by an ordered logit structure which more correctly accounts for the ordinal nature of the indicators.  相似文献   
35.
This paper focuses on recent experiences in the evolution of Flexible Transport Services (FTS). It describes how previous manifestations of FTS provided dedicated solutions for special groups, often in parallel to the conventional public transport network, but highlights that in numerous countries across Europe there is now a discernable trend towards open access FTS providing services for the whole community and often feeding the conventional public transport network to provide wider access and opportunities. This is as a result of policies intended to mainstream services for people with disabilities and moves to tackle social exclusion amongst other groups while at the same time reducing the very high costs per trip associated with STS.To meet these policies, and the higher expectations and different travel behaviours of citizens to-day, it is suggested that FTS will need to radically reposition itself in terms of scale, so that there is mass coverage and ability to function as a full transport mode. This will require breakthroughs in concepts; business models; organisational and operational models; and in supporting technologies. A proposed solution to this is the Flexible Agency for Collective Mobility Services (FAMS) which provides an organisational structure and business model for FTS that incorporates the required supporting technologies.  相似文献   
36.
过去10年,美国环境保护机构已经对铸造工厂施加了更大的压力,以迫使他们减少废弃物的排出. 在金属铸造业,废砂占到整个铸造业废弃物总量的近70%.每生产1 t铸件,大约平均要用363kg砂,这就意味美国铸造工业每年大概要产出700~800万t废砂.  相似文献   
37.
Silicon Controlled Rectifier (SCR) drives have become a standard technique for transit systems. Their utilization meets the most demanding specifications and results in an effective decrease in power consumption which translates in decreased costs for energy. The regenerative DC power may be inverted to 3-phase AC power and returned to the line as usable power. However, regenerative capability is at a cost penalty.  相似文献   
38.
Cars are designed to appeal to the buyer’s self-image, many of them evoking an impression of speed and power. Such an impression conflicts both with the aesthetic language of suburban architecture, and the needs of pedestrians. The research described in this report was conceived as a preliminary investigation of how members of the public view the aesthetic impact of cars in the residential street environment, particularly from the pedestrian’s point of view. The results suggested that people use two distinct sets of criteria when evaluating the motor car and the residential environment in visual terms. When asked to ‘match’ different models of car with different street scenes, respondents avoided referring to abstract visual qualities such as shape, colour and texture, but concentrated instead on the owners: the imagined driver and the imagined householder. The problem of visual harmony was reduced to one of social and cultural harmony. Could the imagined householder be expected to drive this or that car? However, SUVs were singled out as visually intrusive because they blocked the pedestrian’s view. Members of one of the groups, boys aged 11–12, found it difficult to visualise the impact of cars on pedestrians at all, or even to question vehicle design from the pedestrian’s point of view. They just wanted to be in the driving seat.  相似文献   
39.
娜威的6yda油田位于北海南部的UIa和lkofisk之间,于1990年开始投产。该油田是用一个集钻井、膳宿、加工为一体的钢套管架设施开发的。该设施的日产量为将近14000桶原油。  相似文献   
40.
The paper presents a family of disaggregate choice models, which are shown to be equivalent to many of the aggregate models commonly used in planning studies. A brief summary is given of the method that has been developed for estimating the parameters of these models. A generalisation is then introduced in which variables representing the attractiveness in terms of size or quantity of each alternative are allowed to enter the model. It is shown that the form in which these variables enter the model requires a more general estimation algorithm than is commonly used, and such an algorithm is presented. A series of practical tests of the new algorithm is described.  相似文献   
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