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51.
Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues.  相似文献   
52.
This article reports on a study that estimated the economic activity of snorkel-with-whales tourism in the small, isolated island group of Vava'u, Tonga. This research shows that these activities generate important economic and other benefits and that these benefits grew from a relatively modest USD500,000 per year in 1999 to USD5 million per year by 2009. Data from self-reply questionnaires completed by holiday-makers who traveled by aircraft (n = 499) and yacht-based visitors (n = 52) showed that whales have become the predominant attraction for visitors to these remote islands. Interviews with tour operators (n = 10) confirmed the increasing influence of whale based activities over all tourism in the Vava'u area.  相似文献   
53.
Unsteady Reynolds averaged Navier–Stokes (URANS) computations of standard maneuvers are performed for a surface combatant at model and full scale. The computations are performed using CFDShip-Iowa v4, a free surface solver designed for 6DOF motions in free and semi-captive problems. Overset grids and a hierarchy of bodies allow the deflection of the rudders while the ship undergoes 6DOF motions. Two types of maneuvers are simulated: steady turn and zigzag. Simulations of steady turn at 35° rudder deflection and zigzag 20/20 maneuvers for Fr = 0.25 and 0.41 using constant RPM propulsion are benchmarked against experimental time histories of yaw, yaw rate and roll, and trajectories, and also compared against available integral variables. Differences between CFD and experiments are mostly within 10 % for both maneuvers, highly satisfactory given the degree of complexity of these computations. Simulations are performed also with waves, and with propulsion at either constant RPM or torque. 20/20 zigzag maneuvers are simulated at model and full scale for Fr = 0.41. The full scale case produces a thinner boundary layer profile compared to the model scale with different reaction times and handling needed for maneuvering. Results indicate that URANS computations of maneuvers are feasible, though issues regarding adequate modeling of propellers remain to be solved.  相似文献   
54.
1简介 在汽车制造过程中,作为一种金属连接的方式,结构粘合剂的应用正处于迅猛发展阶段。结构粘合剂可增强粘接结构的刚性、耐久性和抗冲撞性。此外.该粘合剂的使用使得相容性差的金属之间的粘接变得容易,因此从成本高低和车体质量大小方面加大了车体结构优化设计的可能性。  相似文献   
55.
Sea-level rise (SLR) is not just a future trend; it is occurring now in most coastal regions across the globe. It thus impacts not only long-range planning in coastal environments, but also emergency preparedness. Its inevitability and irreversibility on long time scales, in addition to its spatial non-uniformity, uncertain magnitude and timing, and capacity to drive non-stationarity in coastal flooding on planning and engineering timescales, create unique challenges for coastal risk-management decision processes. This review assesses past United States federal efforts to synthesize evolving SLR science in support of coastal risk management. In particular, it outlines the: (1) evolution in global SLR scenarios to those using a risk-based perspective that also considers low-probability but high-consequence outcomes, (2) regionalization of the global scenarios, and (3) use of probabilistic approaches. It also describes efforts to further contextualize regional scenarios by combining local mean sea-level changes with extreme water level projections. Finally, it offers perspectives on key issues relevant to the future uptake, interpretation, and application of sea-level change scenarios in decision-making. These perspectives have utility for efforts to craft standards and guidance for preparedness and resilience measures to reduce the risk of coastal flooding and other impacts related to SLR.  相似文献   
56.
Many U.S. bicyclists are killed or injured in traffic accidents annually. Based on analysis of available research and published reports on traffic accidents, it was theorized that adherence to six safety-oriented on-road bicycling practices will reduce involvement in traffic accidents. This study investigated whether adherence to these safety-oriented bicycling practices is associated with reduced involvement in traffic accidents. U.S. adult bicycle riders responded to an anonymous on-line survey covering bicycling practices, recent traffic accident experiences, and potential confounding variables. Participants were recruited via on-line announcements to bicycling-related organizations. The results suggested that neither vigilance nor cautiousness will protect adult bicycle riders from traffic accident involvement, but predictability might reduce accident risk, particularly for younger adults. Results should be interpreted cautiously due to limitations in the study methodology. Further research of this type is warranted.This paper is a re-formulation of research originally presented as a conference paper and oral presentation at the International Cycling Safety Conference in Bologna, Italy, 3–4 November 2016.  相似文献   
57.
ABSTRACT

Anthropogenic climate change poses risks to transport infrastructure that include disrupted operations, reduced lifespan and increased reconstruction and maintenance costs. Efforts to decrease the vulnerability of transport networks have been largely limited to understanding projected risks through governance and administrative efforts. Where physical adaptation measures have been implemented, these have typically aligned with a traditional “engineering resilience” approach of increasing the strength and rigidity of assets to withstand the impacts of climate change and maintain a stable operating state. Such systems have limited agility and are susceptible to failure from “surprise events”. Addressing these limitations, this paper considers an alternate approach to resilience, inspired by natural ecosystems that sense conditions in real-time, embrace multi-functionality and evolve in response to changing environmental conditions. Such systems embrace and thrive on unpredictability and instability. This paper synthesises key literature in climate adaptation and socio-ecological resilience theory to propose a shift in paradigm for transport infrastructure design, construction and operation, towards engineered systems that can transform, evolve and internally manage vulnerability. The authors discuss the opportunity for biomimicry (innovation inspired by nature) as an enabling discipline for supporting resilient and regenerative infrastructure, introducing three potential tools and frameworks. The authors conclude the importance of leveraging socio-ecological resilience theory, building on the achievements in engineering resilience over the past century. These findings have immediate practical applications in redefining resilience approaches for new transport infrastructure projects and transport infrastructure renewal.  相似文献   
58.
In 1987, the government of Kuwait requested permission of the US government to reflag 11 of its tankers to the American flag for the purpose of gaining protection from Iranian attacks. The US government agreed, citing overall strategic and political considerations. As part of the reflagging, waivers were granted to permit the vessels to operate without proper inspections and without licensed radio operators. Furthermore, the vesels employed only one US mariner each, th eecaptain, and though subsequent legislation closed the 'loophole' through which that occurred, anotherr waiver allowed the Kuwaitis to continue without hiring Americans. The maritime policy implications-and the juxtaposition of maritime and foreign policies-were of concern to members of Congress, who held hearings and introduced and passed legislation on the issue.  相似文献   
59.
This paper analyzes transportation attitudes, behaviors and policy preferences in a suburban region. The focus of the study is Orange County, which has experienced rapid growth and industrialization in recent decades. The results from the 1989 Orange County Annual Survey indicate that most residents perceive traffic to be the most serious problem facing the area, and most residents are dissatisfied with the current freeways. Over time, the trend is increased perceptions of traffic problems, However, there is little evidence that residents have changed their driving habits in recent years and there is considerable opposition to new transportation taxes and policies aimed at reducing traffic congestion. These trends are related to opposition to change by affluent suburban residents and to distrust of local government. Traffic attitudes and conservativism appear to play a minor role in predicting current driving habits and policy preferences. The results have important implications for future efforts to improve suburban traffic.  相似文献   
60.
Wardman  Mark  Batley  Richard 《Transportation》2022,49(2):555-589
Transportation - This paper updates and extends the systematic review and meta-analysis of Wardman and Batley (Transportation 41:1041–1069, 2014), which hitherto was the most comprehensive...  相似文献   
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