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1.
Neighborhood services,trip purpose,and tour-based travel   总被引:6,自引:0,他引:6  
Krizek  Kevin J. 《Transportation》2003,30(4):387-410
Communities are increasingly looking to land use planning strategies to reduce drive-alone travel. Many planning efforts aim to develop neighborhoods with higher levels of accessibility that will allow residents to shop closer to home and drive fewer miles. To better understand how accessible land use patterns relate to household travel behavior, this paper is divided into three sections. The first section describes the typical range of services available in areas with high neighborhood accessibility. It explains how trip-based travel analysis is limited because it does not consider the linked (chained) nature of most travel. The second section describes a framework that provides a more behavioral understanding of household travel. This framework highlights travel tours, the sequence of trips that begin and end at home, as the basic unit of analysis. The paper offers a typology of travel tours to account for different travel purposes; by doing so, this typology helps understand tours relative to the range of services typically offered in accessible neighborhoods. The final section empirically analyzes relationships between tour type and neighborhood access using detailed travel data from the Central Puget Sound region (Seattle, Washington). Households living in areas with higher levels of neighborhood access are found to complete more tours and make fewer stops per tour. They make more simple tours (out and back) for work and maintenance (personal, appointment, and shopping) trip purposes but there is no difference in the frequency of other types of tours. While they travel shorter distances for maintenance-type errands, a large portion of their maintenance travel is still pursued outside the neighborhood. These findings suggest that while higher levels of neighborhood access influences travel tours, it does not spur households to complete the bulk of their errands close to home.  相似文献   
2.
AlterationIntroductionThereisastrongini6ractionamongtemPetalrefield,strCssfield,andmicrosttuctutulaltOrationinm8terialsduringtheirhotworking[l'2].Especiallyduringthecoolingprocess,inwhichtemPeratorechangnsgreatly,intendionsbecomemorecomplexbecauseoftransformationoccurmnce.Duringthehotdeformation,thingswillaPpearsuchas:a.hotdeformation,relatedtostressfieId,changesessentiallytheshaPeofmaterialsandcausesthevariationofthecontactstatebetWeenthedieandsample,resultinginchangeofthethermalboundnyco…  相似文献   
3.
近年来在国际航运市场高度竞争趋势下,高等海事教育便成为船员素质养成的重要关键,在现今教育学习多元化的感染下,以学生为主体的学习活动,可增进学生主动探索知识、发现与解决问题,随之激发学生的潜能.本文以学习者本身、教师、学校三大构面来探讨学生学习动机构成因素,并依据学习动机理论结合相关专家学者的实务性教学意见,提出六项激励学习动机的教学策略,以教与学并进的方式规划与培养具有国际竞争能力的高级航海技术人员.在此,学生学习动机将扮演其正向积极的意义与功能.  相似文献   
4.
Korea has achieved remarkable economic growth over the last three decades. This has largely been due to the adoption of export-oriented economic policies. This economic development has resulted in a rapid increase in export and import cargos. Since the foreign trade of Korea is carried predominantly by sea transport (approximately 99.8% in terms of volume), ports play a crucial role in this process. Although recent port developments are aimed at keeping pace with ever-growing seaborne cargoes, problems persist, especially insufficient port capacity and inefficient management and operations. As a consequence, the ports of Korea suffer from serious port congestion. This problem is particularly acute in Pusan, the fifth largest container port in the world. In the past, all ports in Korea were controlled and administered by the Korea Maritime and Port Administration which was a public port authority. In August 1996, the Korean government established a new government organization, the Ministry of Maritime Affairs and Fisheries (MMAF), with a remit to control and manage its seaports and other related activities and to improve management efficiency in the maritime area. As a way of solving problems related to port congestion and other sources of inefficiency, the new MMAF has launched several new port development schemes. In this context, this paper will discuss (1) the extent of congestion in Korean ports, especially Pusan, the major seaport of the country; and (2) governmental and commercial reaction to solving the problems, including measures such as new port development schemes aimed at attracting private and foreign finance. From this analysis, a strategy for port development in developing countries may be inferred.  相似文献   
5.
Eddy systems are a unique ecosystem, usually having high biological masses and primary production in the sea. In this study, both particulate and dissolved phases of cadmium in the water column of 15 stations over a cyclonic eddy in the southern East China Sea were determined to obtain their spatial distributions. This allows us to confirm that cyclonic eddy systems play the role of a Cd pump in the sea.Results showed that particulate Cd (PCd) and dissolved Cd (DCd) concentrations in water varied greatly, ranging over two orders and one order of magnitude, respectively. Large spatial variability was found not only for PCd but also for DCd in the upper water, apparently due to the effects of the cyclonic eddy system on the Cd distributions over the study area. DCd accounts for about 99% of the total Cd. For the surface water, DCd concentration at the eddy center was about five times the average of the water surrounding the eddy center. The depth distributions of DCd exhibited a typical surface depletion and a subsequent increase with depth; however, the PCd distribution showed the opposite, i.e. a surface maximum and a subsequent decline with depth. In general, the DCd maxima were found at depths of 600–1000 m, agreeing well with the literature. It reflected the internal biogeochemical cycling of Cd in the water column, which was driven by the utilization of Cd by plankton in the euphotic zone and by the regeneration of Cd at depth. In addition, a remarkably high DCd concentration existed in near-bottom water around the cyclonic eddy center.The horizontal distributions of both PCd and DCd in the upper water shared a common feature with elevated concentrations centering around the eddy center and a decline in concentration with distance from the eddy center. This shows that the cyclonic eddy could bring up the Cd-rich deep water to the surface water around the eddy center and could then expand toward eddy's vicinity via advection–diffusion. It is thus likely that it produces ample biological masses over the eddy system. Hence, this work can demonstrate that the ascending nutrient-rich water driven by the cyclonic eddies can serve as an important source not only for many nutrients but also for Cd in the sea.  相似文献   
6.
Fang  Kevin  Handy  Susan 《Transportation》2019,46(1):263-283
Transportation - Efforts to promote non-motorized, active transportation modes typically focus on walking and bicycling. However, other self-propelled devices such as skateboards, roller skates,...  相似文献   
7.
8.
The terrorist attacks of 11 September 2001 heightened awareness about the vulnerability of all modes of transportation to terrorist attack. The issue of maritime security has therefore become a major concern in the international maritime sector over the past several years. Globalization has led to a strong growth in seaborne trade; however, it simultaneously increases vulnerability to not only terrorism but also international criminal activities that threaten the world's supply chain. For example, in 2008, the rise in piracy activities in the Gulf of Aden brought the issue of maritime security to the forefront of international debate. In addition to the direct impact on ships, crews and cargoes, and on the maritime industry and governments, piracy also threatens global seaborne trade, and has an impact on energy security and the environment [UNCTAD, 2009, Review of Maritime Transport 2009 (New York: United Nations)]. Maritime piracy can pose substantial risks to seaborne trades, with considerable commodities, ranging between raw materials and energy to high-value manufactured products, being shipped between global economic powerhouses [FU, X. W., NG, A. K. Y., LAU, Y. Y., forthcoming, The impacts of maritime piracy on global economic development: The case of Somalia. Maritime Policy and Management]. Maritime security management, including the definition of security, maritime risk assessment, security measures, the regulation and policy of maritime security in shipping and port-related business operations has been receiving growing attention, both in practice and research.  相似文献   
9.
The purpose of this article is to evaluate the service requirements of dedicated container terminals (DCTs). In this article, the service attributes (SAs) of DCTs were first discussed. A fuzzy analytic hierarchy process model was then constructed to measure the users’ perceived importance and dissatisfaction for each of the SAs. Based on these two measurements, a revised importance-performance analysis model was proposed to identify the SAs that should be improved. To validate the model, the dedicated container terminal of Evergreen Marine Corp. (EMC DCT) at Kaohsiung Port and its users were empirically investigated. With respect to the empirical results, managerial implications of the findings in improving service quality for the EMC DCT are discussed.  相似文献   
10.
This study proposes an aggregate approach to model evacuee behavior in the context of no-notice evacuation operations. It develops aggregate behavior models for evacuation decision and evacuation route choice to support information-based control for the real-time stage-based routing of individuals in the affected areas. The models employ the mixed logit structure to account for the heterogeneity across the evacuees. In addition, due to the subjectivity involved in the perception and interpretation of the ambient situation and the information received, relevant fuzzy logic variables are incorporated within the mixed logit structure to capture these characteristics. Evacuation can entail emergent behavioral processes as the problem is characterized by a potential threat from the extreme event, time pressure, and herding mentality. Simulation experiments are conducted for a hypothetical terror attack to analyze the models’ ability to capture the evacuation-related behavior at an aggregate level. The results illustrate the value of using a mixed logit structure when heterogeneity is pronounced. They further highlight the benefits of incorporating fuzzy logic to enhance the prediction accuracy in the presence of subjective and linguistic elements in the problem.  相似文献   
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