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231.
Peter B. Marlow 《Maritime Policy and Management》2013,40(7):667-676
This paper presents a comment on some of the key issues relating to piracy, terrorism, regulatory approaches and economic issues stemming from maritime security measures. It takes a wide ranging view of these issues and argues that security measures must be managed effectively so as not to be perceived as burdensome. Furthermore, any measures adopted must cover the whole of the international logistics supply chain and not just the shipping component of such distribution channels. 相似文献
232.
Abstract Despite considerable examination of the impact of telecommunications on travel, little empirical evidence sheds light on the impact of e‐shopping on travel—a recent and increasingly popular form of telecommunications. This paper analyses determinants of online buying and their relationship with in‐store shopping, using empirical data obtained from Minneapolis, USA, and Utrecht, the Netherlands. Based on chi‐square tests and logistic and ordinary least‐squares regressions, the results indicate that online buying is affected by sociodemographics and spatial characteristics of people, their Internet experience, and their attitudes towards in‐store shopping. US respondents who prefer to see products in person are less likely to buy online. Dutch respondents are more likely to buy online as travel times to shops are shorter. At first sight, this counterintuitive result might be related to an urban, innovative lifestyle that supports e‐shopping. A more detailed analysis of Dutch online buyers reveals that they make more shopping trips than non‐online buyers and have a shorter shopping duration. The results indicate that the relationship between online buying and in‐store shopping is not one of substitution but of complementarity. 相似文献
233.
Shipping has traditionally been viewed as the least environmentally damaging mode of freight transport. Recent studies have increasingly questioned this perception, as attention has focused on both the greenhouse gas emissions (mainly CO2) and the emission of health-damaging pollutants (such as sulphur, nitrogen oxides and particulates) by ships. This paper reviews the available evidence on the atmospheric emissions of shipping. It proposes that the profit objective has prompted the pursuit of greater fuel efficiency within the sector, but that reliance on market forces alone is insufficient to deliver on the environmental imperative. The paper outlines the current and planned regulatory regime for the atmospheric emissions from ships and posits that greater, and more diverse, market regulation is required. Alternative general approaches to regulatory compliance are categorised as ‘alternative sources of energy’ or ‘abatement technologies’ and the characteristics of a range of specific options are analysed. The paper concludes that although the shipping industry has been slow to improve its environmental credentials, a combination of regulation and technological innovation provides it with significant potential to dramatically reduce its environmental impact. 相似文献
234.
Abstract Road freight transportation has increased dramatically over recent years along with its impacts such as congestion, noise, and pollution. As a result, European and US governments have started policies to promote alternatives to road transportation, such as logistic chains containing a Short Sea Shipping (SSS) link. Road is, by definition, a more flexible means of transportation than shipping, which is usually cheaper. Therefore, to move traffic to SSS chains, it is necessary to provide fast, frequent, and reliable maritime transportation. In this sense, roll-on/roll-off (RoRo) vessels are the most convenient ships to be used, since they have smaller dwell times in port and, therefore, this is a kind of traffic likely to increase dramatically. The foreseeable increase of this kind of traffic must meet with an increase in the actual capacity by means of either improvement in performance and possible enlargements of existing terminals or the construction of new terminals. In that sense, this paper proposes a simple methodology to calculate the capacity of a RoRo terminal, whether already in operation or during its design process, and relate it to some quality standards by means of quality indicators, which should lead to the definition of Levels of Service similar to those already used in roads and airports. The paper ends by applying the methodology to a real terminal in Barcelona, Spain. 相似文献
235.
Transportation specialists, urban planners, and public health officials have been steadfast in encouraging active modes of
transportation over the past decades. Conventional thinking, however, suggests that providing infrastructure for cycling and
walking in the form of off-street trails is critically important. An outstanding question in the literature is how one’s travel
is affected by the use of such facilities and specifically, the role of distance to the trail in using such facilities. This
research describes a highly detailed analysis of use along an off-street facility in Minneapolis, Minnesota, USA. The core
questions addressed in this investigation aim to understand relationships between: (1) the propensity of using the trail based
on distance from the trip origin and destination, and (2) how far out of their way trail users travel for the benefit of using
the trail and explanatory factors for doing so. The data used in the analysis for this research was collected as a human intercept
survey along a section of an off-street facility. The analysis demonstrates that a cogent distance decay pattern exists and
that the decay function varies by trip purpose. Furthermore, we find that bicyclists travel, on average, 67% longer in order
to include the trail facility on their route. The paper concludes by explaining how the distance decay and shortest path versus
taken path analysis can aid in the planning and analysis of new trail systems.
Kevin J. Krizek is an Associate Professor of Planning and Design at the University of Colorado where he directs the Active Communities/Transportation Research Group. His research interests include land use-transportation policies and programs that influence household residential location decisions and travel behavior. He has published in the areas of transportation demand management, travel behavior, neighborhood accessibility, and sustainable development. He earned a Ph.D. in Urban Design and Planning and M.S.C.E. from the University of Washington in Seattle. His master’s degree in planning is from the University of North Carolina at Chapel Hill and his undergraduate degree is from Northwestern University. Ahmed El-Geneidy is a Post-Doctoral research fellow at the Department of Civil Engineering, University of Minnesota and Humphrey Institute of Public Affairs. El-Geneidy’s research interests include transit operations, travel behavior, land use and transportation planning, and accessibility/mobility measures in urban areas. He earned B.S. and M.S. degrees from the Department of Architectural Engineering at the University of Alexandria, Egypt, and continued his academic work at Portland State University, where he received a Graduate GIS Certificate and earned a Ph.D. in Urban Studies from Nohad A. Toulan School of Urban Studies and Planning. Kristin Thompson was a research assistant with ACT and currently works for Metro Transit in Minneapolis, Minnesota. 相似文献
Ahmed El-GeneidyEmail: |
Kevin J. Krizek is an Associate Professor of Planning and Design at the University of Colorado where he directs the Active Communities/Transportation Research Group. His research interests include land use-transportation policies and programs that influence household residential location decisions and travel behavior. He has published in the areas of transportation demand management, travel behavior, neighborhood accessibility, and sustainable development. He earned a Ph.D. in Urban Design and Planning and M.S.C.E. from the University of Washington in Seattle. His master’s degree in planning is from the University of North Carolina at Chapel Hill and his undergraduate degree is from Northwestern University. Ahmed El-Geneidy is a Post-Doctoral research fellow at the Department of Civil Engineering, University of Minnesota and Humphrey Institute of Public Affairs. El-Geneidy’s research interests include transit operations, travel behavior, land use and transportation planning, and accessibility/mobility measures in urban areas. He earned B.S. and M.S. degrees from the Department of Architectural Engineering at the University of Alexandria, Egypt, and continued his academic work at Portland State University, where he received a Graduate GIS Certificate and earned a Ph.D. in Urban Studies from Nohad A. Toulan School of Urban Studies and Planning. Kristin Thompson was a research assistant with ACT and currently works for Metro Transit in Minneapolis, Minnesota. 相似文献
236.
J. Son B. Reimer B. Mehler A. E. Pohlmeyer K. M. Godfrey J. Orszulak J. Long M. H. Kim Y. T. Lee J. F. Coughlin 《International Journal of Automotive Technology》2010,11(4):533-539
Driving demands significant psychomotor attention and requires even more when drivers are engaged in secondary tasks that
increase cognitive workload and divert attention. It is well established that age influences driving risk. Less is known about
how culture impacts changes in attention. We conducted parallel driving simulations in the US and Korea to measure the extent
to which age and culture influence dual-task performance. There were 135 participants divided into two groups: a younger group
aged 20∼29, and an older group aged 60∼69. Whereas some differences by culture appeared in absolute control measures, the
younger participants showed similar mean velocity and compensatory patterns associated with increased cognitive load in the
urban setting; however, the results from the older samples were less similar. 相似文献
237.
D. García-Pozuelo Ramos A. Gauchía B. L. Boada V. Díaz 《International Journal of Automotive Technology》2010,11(5):691-699
Vehicle systems such as the steering, brakes and suspension greatly influence vehicle safety. Therefore, these systems must
be inspected to guarantee that they are functioning correctly and to certify that the vehicle is functioning at a satisfactory
safety level. In disc brakes, warping is one of the principal reasons for vibrations and noise, and it contributes to diminished
brake efficiency. Currently, the International Motor Vehicle Inspection Committee (CITA) demands disc brake warping inspections
occur during periodic motor vehicle inspections (PMVIs); however, the procedure to carry out this inspection is not well defined.
In this investigation, the warping phenomenon has been analyzed, and a new inspection procedure is proposed. 相似文献
238.
D. K. Park C. D. Jang S. B. Lee S. J. Heo H. J. Yim M. S. Kim 《International Journal of Automotive Technology》2010,11(4):489-494
This paper presents a design technique to optimize the shape of a vehicle bumper beam that satisfies both the safety requirements
for a front rigid-wall impact and the regulations protecting pedestrians from lower leg injuries caused by bumper impacts.
An intermediate response surface modeling (IRSM) technique was introduced to approximate the non-linear force-displacement
curves obtained from the front impact analysis of a vehicle bumper. The accuracy of the IRSM model was tested by comparing
its results with those of the non-linear finite element analysis. The maximum displacement error between the two models did
not exceed 3%. Using pedestrian impact analyses based on the experimental arrangement of the Plackett-Burman design, the approximate
functions describing the response values acting on the lower legs were calculated. The shape of the bumper beam was optimized
by integrating the IRSM with the force-displacement model and the approximate functions on lower leg impact. The optimization
results satisfied safety regulations on the maximum allowable displacement of the vehicle bumper, and also the regulations
protecting pedestrians from lower leg injuries caused by bumper impacts. 相似文献
239.
S. B. Han Y. H. Chang E. Y. Lee Y. J. Chung B. Suh 《International Journal of Automotive Technology》2010,11(1):105-110
Hybrids combine a combustion engine with an electric motor and battery. The two technologies can be combined to reduce fuel
consumption and exhaust emissions. This paper presents the concept of hybrid electric vehicles (HEVs) applied to truck or
van vehicles with diesel engines. The simulation results from the advanced vehicle simulator (ADVISOR) demonstrate that the
required power may be properly shared between the internal combustion engine and electric motor. The simulation can also be
used to prove that the technique is useful for improvements in driving performance; additionally, the technique is suitable
for hybrid electric vehicles, allowing for good fuel economy and low emissions performance. 相似文献
240.
B. H. Lee J. H. Song Y. J. Chang C. H. Jeon 《International Journal of Automotive Technology》2010,11(6):783-791
The diesel combustion process is highly dependent on fuel injection parameters, and understanding fuel spray development is
essential for proper control of the process. One of the critical factors for controlling the rate of mixing of fuel and air
is the number of injector holes in a diesel engine. This study was intended to explore the behavior of the formation of spray
mixtures, combustion, and emissions as a function of the number of injector hole changes; from this work, we propose an optimal
number of holes for superior emissions and engine performance in diesel engine applications. The results show that increasing
the number of holes significantly influences evaporation, atomization, and combustion. However, when the number of holes exceeds
a certain threshold, there is an adverse effect on combustion and emissions due to a lack of the air entrainment required
for the achievement of a stoichiometric mixture. 相似文献