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221.
Mature hub ports in the free trade environment,the way forward from a global supply chain perspective: an Asian case 总被引:1,自引:0,他引:1
Asia-Pacific countries with divergent economic and political backgrounds developed a regime of bilateral free trade agreements in response to globalization. Challenged by the 1997 and 2008 financial crises, this Asian trade regime has remained intact, although the most powerful stakeholders have changed positions, as indicated by the strong emergence of China in the past decade. Efforts of key trading partners to tackle non-tariff barriers (e.g., rule of origin and customs formalities) in the region have yielded little progress thus far. Instead of aiming at a regional consensus on non-tariff barriers by all member states, a global supply chain (GSC) approach is recommended. Mature hub ports at strategic locations with advanced institutional measures could set up international trade facilitation centers co-locating multinational customs formalities. This GSC approach may also be adopted to construct a GSC hub development model that explains the transformation of hub ports. 相似文献
222.
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
223.
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
224.
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
225.
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
226.
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
227.
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
228.
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
229.
Active coolant control strategies in automotive engines 总被引:1,自引:0,他引:1
K. B. Kim K. W. Choi K. H. Lee K. S. Lee 《International Journal of Automotive Technology》2010,11(6):767-772
The coolant flow rate in conventional cooling systems in automotive engines is subject to the mechanical water pump speed,
and high efficiency in terms of fuel economy and exhaust emission is not possible given this limitation. A new technology
must be developed for engine cooling systems. The electronic water pump is used as a substitute for the mechanical water pump
in new engine cooling systems. The new cooling system provides more flexible control of the coolant flow rate and engine temperature,
which previously relied strongly on engine driving conditions such as load and speed. In this study, the feasibility of two
new cooling strategies was investigated using a simulation model that was validated with temperatures measured in a diesel
engine. Results revealed that active coolant control using an electronic water pump and valves substantially contributed to
a reduction of coolant warm-up time during cold engine starts. Harmful emissions and fuel consumption are expected to decrease
as a result of a reduction in warm-up time. 相似文献
230.
T. -Y. Koo B. -Y. Kim H. -J. Shin Y. -T. Son S. -W. Kim M. -W. Suh 《International Journal of Automotive Technology》2010,11(5):743-749
Driving simulators are useful tools that can be used not only to test the components of future cars, but also to evaluate
the telematics service and HMI (Human-Machine Interface). However, driving simulators that are currently available cannot
be implemented to test and evaluate a real commercial telematics service system because the GPS (Global Positioning System),
which contains basic functional support for the telematics module, does not work in the VR (virtual reality) environment.
A driving simulator, together with the GPS simulator, can be used to study the HMI to evaluate commercial CNS (Car Navigation
Systems). In this paper, Sungkyunkwan University Driving Simulator (SKUD) is developed with a GPS simulator that is able to
emulate GPS satellite signals and includes the NMEA-0183 protocol and RS232C communication standards. Furthermore, using the
SKUD, the HMI of the real commercial CNS could be investigated with driver workload assessment methods. 相似文献