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11.
法拉利派对     
2011年4月17日,上海——2011年F1上海大奖赛拉开战幕,法拉利中国车主齐聚上海,与法拉利车队一起尽享赛道激情。决赛当日,法拉利在华经销商及数十位车主携其爱驾组成车队,在上海国际赛车场举行别开生面的赛道巡游,这是F1自1950年创始以来,  相似文献   
12.
A framework for assessing convergence and validation of non-intrusive uncertainty quantification (UQ) methods is studied and applied to a complex industrial problem in ship design, namely the high-speed Delft Catamaran advancing in calm water, with variable Froude number and geometry. Relationship between UQ studies and deterministic verification and validation is discussed. Computations are performed using high- (URANS) and low- (potential flow) fidelity simulations. Froude number has expected value and standard deviation equal to 0.5 and 0.05, respectively, on a truncated normal distribution. Geometric uncertainty is related to the research space of a simulation-based design optimization, and assessed through the Karhunen–Loève expansion (KLE). Monte Carlo method with Latin hypercube sampling (MC-LHS) is used to compute expected value, standard deviation, distribution and uncertainty intervals for resistance, sinkage and trim. MC-LHS with CFD is used as a benchmark for validating less costly UQ methods, including MC-LHS with metamodels and standard quadrature formulas. Gaussian quadrature is found the most efficient method; however, MC-LHS with metamodels is preferred since provides with confidence intervals and distributions in a straightforward way and at reasonably small computational cost. UQ results are compared to earlier deterministic single- and multi-objective optimization; reduced-dimensional KLE studies for geometric variability indicate that stochastic optimization would not be of great benefit for the present problem.  相似文献   
13.
This paper deals with the measurement of the network complexity of some selected shipping groups, also identifying the contribution of co-operative agreements among carriers. The empirical investigation is focused on: (i) the analysis of the distribution of the carrying capacity per range; and (ii) the comparison of that capacity with the throughput handled in the port facilities of the group. These variables are interpreted in the light of the impact that alliances have on the geographical wideness of the services supplied by each partner. This factor also allows to depict how the cultural and political origin of shipping lines affects the decision of joining an alliance and the outcomes deriving from such co-operation.  相似文献   
14.
Abstract

Traditional transport infrastructure assessment methodologies rarely include the full range of strategic benefits for the transportation system. One of these benefits is the contribution to cross‐border integration, critical for the European integration process. However, this is a key issue in strategic planning and decision‐making processes, as its inclusion may increase the probability of large‐scale transport infrastructure projects being funded. This paper presents a methodology for the measurement of the contribution of transport infrastructure plans to European integration. The methodology is based on the measurement of the improvement in network efficiency in cross‐border regions of neighbouring countries, via accessibility calculations in a Geographical Information System support. The methodology was tested by applying it to the ambitious road and rail network extensions included in the Spanish Strategic Transport and Infrastructure Plan (PEIT) 2005–2020. The results show significant and important network efficiency improvements of the PEIT outside the Spanish border. For the road mode, while the Spanish average accessibility improvement accounts for 2.6%, average improvements in cross‐border regions of France and Portugal are of 1.8%. And for the rail mode, the corresponding Spanish value is 34.5%, whereas in neighbouring regions it accounts for 20.2%. These results stress the significant importance of this strategic benefit and the consequent need for its inclusion in strategic planning processes. Finally, the paper identifies the potential of the methodology when applied at different administrative levels, such as the local or state levels.  相似文献   
15.
The main objective of this paper is ‘to assess the conditions, including policy support, under which innovative concepts have a high chance of getting adopted and being successful’. The work will start from the state-of-the-art with the following goals targeted. Firstly, to identify the paths that new innovative concepts usually follow, what key determinants are, which actors are involved, and what policy has been doing and can do. As part of this, a typology of variables is established, which will be the basis for the identification of successful adoption paths. Illustrations are provided of the performance of different innovative concepts in the seaport sector. A further goal is to propose policy recommendations, identify best practices, barriers to implementation and transferability of innovative concepts and processes. Finally, the research establishes developments needed in assessment methods and a methodological framework if innovative concepts are introduced.  相似文献   
16.
Modern ports need to be inserted in an efficient network in order to exploit all their potential, positively affecting both the efficiency of the local markets and the external costs of the served industries. Moreover, the role of the ports within the whole supply chain is affected by the location and the organization of intermediate facilities—such as logistics parks or inland ports—that heavily influence both the effectiveness of the logistics corridors and the externalities generated by the transport industry. New and adequate infrastructures can then reduce congestions, pollution, and accidents smoothing the whole logistics chains. The proposed study aims at discussing the effects in terms of rail share of the different planned interventions that are aimed at increasing the rail capacity of the network under investigation. In order to achieve this goal, a network optimization model has been solved by the optimizer solver of a spreadsheet. Outcomes can be used in order to improve current transport policies that might foster a more efficient and less impacting hinterland transport solution.  相似文献   
17.
During the February 1981 cruise FIBEX MD-25 between 30–50°E and 61–64°S, hydrography showed the presence of two gyres, confirmed by the geostrophic circulation relative to 1000 m from Levitus climatology, at the borders of these gyres concentrations of highly morphologically differentiated krill were found. Gaussian component analysis of krill samples, pooled by sectors, showed three cohorts of Euphausia superba in the western sector and one in the eastern sector. Across the sampling area, Thysanoessa macrura and E. superba occurred at separate stations. Analysis of cohorts in T. macrura separated two size groups in both the western and the eastern sectors. The use of a Differentiation Index (D.I.) [Färber-Lorda, J., 1990. Somatic length relationships and ontogenetic morphometric differentiation of Euphausia superba and Thysanoessa macrura of the southwest Indian Ocean during summer (February 1981). Deep-Sea Res. 37, 1135–1143.], based on somatic lengths, allows studying certain morphological differences within the populations sampled. Morphologically different and bigger males II (D.I. from 2.8 to 3.5) were present only in the southern transect while smaller males I (D.I. from 3.5 to 5.0) were present over the entire area. Biochemical composition of both species showed significant differences among stations for protein, lipids, and carbohydrates. A significant difference in lipid content was found between males I, and males II. For T. macrura, percentage of lipid content in mature animals was much higher than that in E. superba. The D.I. size distribution showed that when populations of E. superba were highly differentiated (corresponding to mature animals) in morphology, lipid content was high, and they were located near a gyre. Differences in morphometry can influence distribution of the species, because different developing stages have different swimming capacities. It is shown that, together with hydrography and trophic conditions, lipid content and morphometry of krill populations, are different but complementary aspects that help to understand krill ecology and distribution.  相似文献   
18.
中庭式地铁车站因用大量横梁取代楼板来形成中庭大开口(顶层和中层楼板的开口率均超过50%),且站厅层无柱,站台层采用宽高比达7.5的薄壁柱,车站结构抵抗横向变形比如地震作用的能力,成为值得担忧的一个问题.为此,针对埋置于人工模型土中的中庭式地铁车站模型,进行了一系列1g振动台试验,探究中庭式地铁车站结构的地震响应特征,以...  相似文献   
19.
Biological control of harmful algal blooms: A modelling study   总被引:1,自引:0,他引:1  
A multispecies dynamic simulation model (ERSEM) was used to examine the influence of allelopathic and trophic interactions causing feeding avoidance by predators, on the formation of harmful algal blooms, under environmental scenarios typical of a Mediterranean harbour (Barcelona). The biological state variables of the model included four functional groups of phytoplankton (diatoms, toxic and non-toxic flagellates and picophytoplankton), heterotrophic flagellates, micro- and mesozooplankton and bacteria. The physical–chemical forcing (irradiance, temperature and major nutrient concentrations) was based on an actual series of measurements taken along a year cycle in the Barcelona harbour. In order to evaluate potential effects of advection, some runs were repeated after introducing a biomass loss term. Numerical simulations showed that allelopathic effects of a toxic alga on a non-toxic but otherwise similar competitor did not have appreciable influence on the dynamics of the system. However, induction of avoidance of the toxic alga by predators, which resulted on increased predation pressure on other algal groups had a significant effect on the development of algal and predator populations. The presence of advection overrided the effect of these interactions and only allowed organisms with sufficiently high potential growth rates to thrive.  相似文献   
20.
The present study considers underground passengers and investigates the ways in which they spend their time during a trip of average length or shorter. Using a structured procedure that had been refined after a preliminary study, more than 1,700 passengers were observed in London. The results showed that even when the length of travel is very short (2–6 stops), underground passengers engage in several occupations, especially those involving the use of mobile Information and Communication Technologies. These occupations depend on the specific spatial and temporal conditions of the travel, as well as on gender and age. These results should be useful in designing travel services that enhance passengers’ experiences; they also suggest a criterion for comparing trips using different transportation modes (i.e., looking at the time point during the trip at which the ratio of active versus passive occupations changes).  相似文献   
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