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排序方式: 共有1965条查询结果,搜索用时 15 毫秒
971.
The paper reviews the need for a better understanding of the factors which affect the location of freight facilities, such as depots, terminals, freight forwarding centres, distribution centres, etc. The development of an Elimination by Aspects (EBA) model to analyse such location decisions by the managers of freight firms is described. The results are shown to be comparable (perhaps even superior to) those obtained with a logit model. Conclusions are drawn with respect to both the use of the EBA model to analyse freight facility location preference, and the factors which affect such preference. Five factors were found to be significant: closeness to existing customers, closeness to arterial roads, availability of suitable sites, cost of truck fleet operation, and closeness to labor.  相似文献   
972.

A trio of closely related land‐use/transport interaction models was developed using Marcial Echenique & Partners’ software package MEPLAN. The models were for the cities of Bilbao, (Spain), Dortmund (West Germany) and Leeds (England). All were calibrated using data drawn from earlier studies. The three models were used to predict the effects (relative to a base case) of a common programme of land‐use and transport policies or scenarios. This paper explains briefly the theoretical basis of the MEPLAN package as applied to urban models such as these three; describes the types of policies that have been assessed; and presents some of the key results.  相似文献   
973.
Canada’s west coast has been a hotspot of environmental conflict, most recently in defense of climate action and natural places under threat by energy development. This study examined sense of place as a source of tension in conflicts sparked by two energy proposals. The Bute Inlet run-of-river hydroelectric project would power British Columbia’s remote Central Coast, and the Trans Mountain pipeline expansion would transport bitumen from Alberta’s oil sands to tankers for export. Surveys, interviews, and mapping were used to investigate the depth and character of participants’ sense of favorite places and places expected to be affected by the projects, with appreciation, concern, and responsibility for nature as organizing themes. We discovered a regional, nature-centric sense of place on the south coast, and a sense of place among Albertans linked to that province’s oil and gas economy and its reputation as Canada’s chief breadwinner. Ties to natural places were found to underpin environmental advocacy by tapping into deep place connections as well as place connections conveyed through network ideologies and the protests themselves. We outline for consideration key characteristics of a regional sense of place, and offer ways to mitigate place-based economy versus environment conflicts.  相似文献   
974.
Yeh  Chao-Fu  Lee  Ming-Tsung 《Transportation》2019,46(1):1-16
Transportation - Since 2001, the Taichung City Government has launched several policies to stimulate public transit ridership. Based on this successful experience of reforming the urban bus system,...  相似文献   
975.
Journal of Marine Science and Technology - Autonomous surface vehicles are gaining increasing attention worldwide due to the potential benefits of improving safety and efficiency. This has raised...  相似文献   
976.
ABSTRACT

From simple organizations as gateways for goods and passengers, ports have evolved and transformed into complex organizational systems with multiple functions. Besides providing cargo, logistics, and other kinds of services to its customers, modern ports engage in the development of their hinterlands. Sustainability, evolving from environmental actions over the years, has become the core of many modern ports’ approach towards hinterland development and port competitiveness. While the literature is concerned with and presents examples of large ports implementing sustainability initiatives, the literature is scarce on smaller ports. This article addresses this gap by exploring qualitatively the case of the Port of Aalborg, a medium-sized port in Denmark, and its evolution towards using sustainability for port and hinterland development. The research focuses on the actions behind environmental development at the port. Its evolution is mapped and explored using the analytical framework developed based on the (larger) ports’ development and their roles. The findings from the Port of Aalborg case exemplify how smaller ports can evolve to drive the sustainable development of their hinterlands and contribute to a better understanding of this kind of port.  相似文献   
977.
[Objective]This paper aims to establish a dynamic model of a floating raft vibration isolation system with a liquid tank in order to study the mass effect of the liquid medium, tank form, structural stiffness and loading rate on acoustic performance. [Methods]A floating raft system with a cuboidal or cylindrical liquid tank is taken as the research object, and a fluid-structure coupling finite element dynamic model is established. The dynamic force transmission rate and power flow are then used to evaluate the acoustic performance of the system. The influence of the mass effect of the liquid medium, tank form, structural stiffness and loading rate of tank volume on the acoustic performance of the floating raft system are analyzed.[Results]The results show similar laws obtained through the calculation and analysis of the floating raft system with two types of tanks. The structural stiffness of the tank affects the mass effect of the liquid medium in the tank to a certain extent. [Conclusions]If full advantage is to be taken of the liquid mass effect in the tank with a large loading rate to improve the acoustic performance of the floating raft system, the design of the liquid tank and raft structure must have sufficient stiffness. In addition, under the condition that the floating raft structure has sufficient stiffness, its acoustic performance will improve significantly as the tank loading rate increases in the relevant low frequency range. © 2022 Journal of Clinical Hepatology. All rights reserved.  相似文献   
978.
Fishneck, a small and isolated fishing community in the Chesapeake Bay area, has been characterized by low education levels, few suprafamilial organizations, and little participation in institutions outside the community. Community members have resisted proletarianization through barter, exchange, supplemental wage labour, fill-in work, and family mutual aid.

These patterns are changing as contact increases with the wider society. Leisure is identified as the strongest pull toward participation. Results of greater contact include a more positive image to outsiders, a sharpened sense of community and community boundaries, and greater participation in the educational, economic, and political arenas. Whether this community changes toward a small-town fishing hamlet depends first on moving from clan-based to community-based internal organization.  相似文献   
979.
This paper focuses on a fuzzy logic based intelligent decision making system that aims to improve the safety of marine vessels by avoiding collision situations. It can be implemented in a decision support system of an oceangoing vessel or included in the process of autonomous ocean navigation. Although Autonomous Guidance and Navigation (AGN) is meant to be an important part of future ocean navigation due to the associated cost reduction and improved maritime safety, intelligent decision making capabilities should be an integrated part of the future AGN system in order to improve autonomous ocean navigational facilities. In this study, the collision avoidance of the Target vessel with respect to the vessel domain of the Own vessel has been analyzed and input, and output fuzzy membership functions have been derived. The if–then rule based decision making process and the integrated novel fuzzy inference system are formulated and implemented on the MATLAB software platform. Simulation results are presented regarding several critical collision conditions where the Target vessel fails to take appropriate actions, as the “Give way” vessel to avoid collision situations. In these situations, the Own vessel is able to take critical actions to avoid collisions, even when being the “Stand on” vessel. Furthermore, all decision rules are formulated in accordance with the International Maritime Organization Convention on the International Regulations for Preventing Collisions at Sea (COLREGs), 1972, to avoid conflicts that might occur during ocean navigation.  相似文献   
980.
The dynamic response of planing vessels in regular head seas is investigated numerically. Nonlinear time domain simulations were performed using a 2D + t theory (two-dimensional plus time dependent theory). A prismatic hull form was assumed. We employed a two-dimensional (2D) boundary element method to solve the initial boundary value problems in 2D cross planes, in which nonlinear free-surface conditions and exact body boundary conditions were satisfied. At each time step, the total force and moment on the hull could be obtained by using the sectional forces calculated in those 2D planes. Heave and pitch motions were then acquired by solving the equations for those motions. The calculated heave and pitch responses were compared with the experiments by Fridsma (A systematic study of the rough-water performance of planing boats. Davidson Laboratory Report R-1275, 1969) for two different Froude numbers. Three-dimensional (3D) corrections at the transom stern were applied to show the influence of the 3D effect at the stern on the numerical results. Ship motions were affected by the 3D corrections, especially near the resonance frequency, while the phase angles were slightly affected and the acceleration peaks at the bow near the resonance frequency were sensitive to the 3D corrections. Other error sources in the theoretical results are also mentioned.  相似文献   
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