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31.
Transportation - In this paper, an optimisation model for recovery planning of road networks is presented in which both social and economic resilience is aimed to be achieved. The model is... 相似文献
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Robert Thompson 《Coastal management》2013,41(2-3):211-237
Along the coast we witness property conflicts that would seem strange at inland locations. To understand why property conflicts seem particularly common and intense along shorelines, one must appreciate that property is enacted by real people in specific places. The successful enactment of property requires sufficiently shared expectations for behavior. Expectations are formed by consulting cultural models, which are inter-subjectively shared cognitive tools. This article describes seven cultural models of property that can play a role in the enactment of property along the shoreline. These are the sovereignty, community, landscape, ecology, commodity, moral order, and productivity models. A focus on cultural models shows how property conflicts can occur when models are not adequately grounded in real world circumstances, when a cultural model is not shared, or when multiple cultural models conflict. This article argues that all three of these types of failures are more likely to occur along shorelines than with inland property. Finally, even though cultural models of property are not hierarchical, this article argues that too much emphasis is currently being placed on the sovereignty and commodity models, and it suggests ways to reestablish a better balance between all of the cultural models of property. 相似文献
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Jean C. Kenyon Russell E. Brainard Ronald K. Hoeke Frank A. Parrish Casey B. Wilkinson 《Coastal management》2013,41(3):339-349
An integrated method for benthic habitat assessment is described, in which divers maneuver boards equipped with digital video, temperature, and depth recorders while being towed behind a small boat. The tow path is concurrently recorded by a GPS receiver, and a layback model is applied to more accurately map the data. Percent cover of salient benthic categories is quantified by whole-image analysis of still frames sampled at 30-s intervals. The results of 15 towed-diver surveys at Midway Atoll in the Hawaiian Archipelago during a mass coral bleaching event are presented to exemplify the method and are compared to results derived from conventional methods. Towed-diver surveys bridge a gap between large-scale mapping efforts using satellite data and small-scale, roving diver assessments, providing a mesoscale spatial assessment of reef habitats. The spatial coverage of towed-diver surveys provides comprehensive data to managers concerning the extent, intensity, differential taxonomic response, and bathymetric correlates of bleaching. 相似文献
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B. R. Davis A. G. Thompson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2001,35(6):409-415
The road profile is usually considered to be a random process x ( d ), where x is the road height and d is the distance along the road. As the vehicle travels along the road with velocity v , the random process x ( d ) is converted to a random process x ( t ) which is input to the vehicle suspension via the tyre. The random process x ( d ) is usually described in terms of its power spectral density as a function of frequency in either radians or cycles per unit distance. However, there are several different ways of defining power spectral density, and this makes it difficult to compare published data without knowing how the power spectral density has been defined. The proper calculation of RMS values of vehicle response for an assumed road power spectral density is explained by an example. 相似文献
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David J. Thompson Georges Kouroussis Evangelos Ntotsios 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(7):936-983
ABSTRACTThere is a great need to develop rail networks over long distances and within cities as more sustainable transport options. However, noise and vibration are seen as a negative environmental consequence. Compared with airborne noise, the related problem of ground vibration is much more complex. The properties of the ground vary significantly from one location to another. There is no common assessment criterion or measurement quantity and no equivalent to the noise maps. Ground-borne vibration is transmitted into buildings and perceived either as feelable whole-body vibration or as low frequency noise; it can also affect sensitive equipment but it is generally at a level that is too low to cause structural or cosmetic damage to buildings. A review is given of evaluation criteria for both feelable vibration and ground-borne noise, empirical and numerical prediction methods, the main vehicle and track parameters that can affect the vibration levels and a range of possible mitigation methods. 相似文献
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A. G. Thompson B. R. Davis 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1988,17(4):179-192
In optimally controlled active suspensions with either full or incomplete state feedback there is tradeoff between system performance and overall stiffness. It is sought to remove this limitation by incorporating integral action which results in a system with infinite stiffness towards static loading, but which is soft with respect to road inputs. The system is also able to eliminate the steady state deflections due to step and (potentially) ramp type inputs at the wheel. Optimality is retained at the cost only of a derivative constraint and the system can be physically realised using output feedback control. 相似文献
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Little is known about the sources of public support for transit systems even though the perceptions of transit users and potential users have been extensively documented. Research reported here examines dimensions of public support for the first U.S. downtown people mover during three critical phases in the system's life: construction, shakedown, and operations. The method employed was a community sample survey with home interviews. Data analysis showed that the public—who were virtually all nonusers—were largely favorable toward the system during the construction phase. During the shakedown phase, when system reliability was extremely low, many attitudes toward the system became less favorable, especially perceptions of performance and direct community impacts. Later, reliability improved, and attitudes which had become less favorable tended to grow more favorable once again. It is suggested that a system's performance can influence many aspects of public support for a transit system, even among nonusers. This pattern has implications for system planners who must depend on public good will for continuing support of transit systems. In particular, extensive pretesting of new systems should occur before the fare gates are opened to patrons. 相似文献
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Abstract Designing environmental monitoring programs to deal with widespread, subtle, and/or cumulative impacts on a regional basis is challenging. It requires a shift away from focusing primarily on individual point sources to a more regional perspective. It also necessitates involving scientists and managers together in a cooperative effort to establish priorities and articulate clear objectives. In our view, this objective‐setting task is neither a strictly scientific nor a strictly management activity. It depends on effective communication between scientists and managers but is confounded by differing perspectives, value systems, and behaviors. We present a conceptual framework to assist managers and scientists in this process. This is intended to structure such communication by helping to create a context that permits fruitful give‐and‐take between the two groups. We then describe a six‐part model for specifying the key elements of regional monitoring objectives. 相似文献