排序方式: 共有223条查询结果,搜索用时 31 毫秒
191.
Young-Tae Chang Shu-Min Liu Hyosoo Park Younghoon Roh 《Maritime Policy and Management》2013,40(4):483-494
ABSTRACTNo studies have been conducted on cruise traveler expectations for a port of call in Asia. Current literature on general tourism shows that the research to measure traveler satisfaction is divided into two dominant approaches, the disconfirmation model, based on the Expectancy Disconfirmation Paradigm, and the perceptions-only model. However, previous disconfirmation models used different sample populations to measure traveler expectations and perceptions, resulting in biased results. The main objectives of this research was two-fold: (1) to develop a measurement scale for evaluating the expectations of cruise travelers during their visit to a port of call; and, (2) to examine the satisfaction of cruise travelers using the same sample population of the pre-visit expectations and post-visit experiences. The measurement scale for cruise travelers was developed using exploratory factor analysis and confirmatory factor analysis. Three factors, “Overall convenience/People,” “Culture/Exploration,” and “Commodities/Attractions,” were extracted from the analysis. Among these factors, the “Culture/Exploration” factor explained the largest part of overall satisfaction. The results also showed that the perception-only model outperformed the disconfirmation model in explaining overall satisfaction. Additionally, overall satisfaction was found to have a greater impact on the intention to recommend the visit to others than on the intention to revisit. 相似文献
192.
Abstract This paper investigates how air passengers’ expectations, ticket price, airline service quality, value, passenger satisfaction and airline image determine their buying behaviour. To test the conceptual frameworks, path analysis was applied to data collected from Korean and Australian international passengers to examine differences between these two groups. Further analyses were undertaken on different passenger segments between national and foreign airline passengers. The results of the path analysis reveal that air passengers’ buying behaviour differs significantly between Korean and Australian international passengers. Results also reveal that the determinants of air passengers’ buying behaviour differ by airlines. 相似文献
193.
Jong Hyeon Park Chan Young Kim 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1999,31(4):263-278
Traction control systems are used to prevent wheel slippage and to maximize traction forces. This paper proposes a new scheme to enhance vehicle lateral stability with a traction control system during cornering and lane changes. This scheme controls wheel slip during cornering by varying the slip ratio as a function of the slip angle. It assumes that a traction control system with the engine throttle angle is used. The scheme is dynamically simulated with a model of front-wheel-driven passenger vehicles. Simulation results show that the proposed scheme is robust and superior to a conventional one, which is based upon fixed slip ratios, during cornering and lane changes. 相似文献
194.
Many plants can accumulate glycine betaine(GlyBet, N, N, N-trimethylglycine), an non-toxic or osmo-protectant in response to salinity anddrought stress. Numerous experiments in vitrohave indicated that betaine acts as an osmoprotec-tant by stabilizing both the quaternary structure ofproteins and the highly ordered structure of mem-branes against the adverse effects of high salinityand extreme temperatures. Exogenous applicationof betaine to leaves or roots has been shown to in-crease the tol… 相似文献
195.
Jongryeol Jeong Namwook Kim Wonsik Lim Yeong-Il Park Suk Won Cha Myeong Eon Jang 《International Journal of Automotive Technology》2017,18(5):891-900
In a hybrid electric vehicle (HEV) system, it is an important issue on how to distribute the output power from multiple power generating components to operate a vehicle more efficiently. Many studies have been conducted on how to manage multiple power sources of a vehicle based on various optimization theories. In this study, an algorithm to calculate the optimization of a series HEV that has three power generating components, engine, battery and ultra-capacitor, is developed based on dynamic programming. Normally dynamic programming is applied to the optimization of power management and components sizing by estimating potential fuel economy for electrified vehicle such as HEV, Plug-in HEV or Fuelcell HEV. In contrast with most objective systems that have only two power generating components, the system in this study has three power sources. Since the system has three power sources, the number of state and control variables of optimization problem increases. Therefore the number of calculations increases unreasonably. To decrease the number and time of calculations, a new electric model that contains the both characteristics of battery and ultra-capacitor is developed with some assumptions. In comparison with the optimization algorithm which follows the theory of DP with no assumptions, the results from the newly developed algorithm has 1.04 % discrepancy in terms of fuel economy, even though the calculation time decreases to 4400 times less. 相似文献
196.
Myeong Jun Kim Tae Won Park In Kyeong Hwang In Chul Sung Hyoung Seok Kim Sang Do Na Sung Pil Jung Tae Hee Lee Kyung Up Mah Jae Yun Lee 《International Journal of Automotive Technology》2017,18(6):973-981
Worldwide, the tire market requires safe and eco-friendly tires. In this study, a self-inflating tire (SIT) was studied and manufactured. Self-inflating tire refers to a technique for maintaining appropriate tire pressure. An internal regulator senses when tire inflation pressure has dropped below the set air pressure. The tire boosts air through the valve when rolling and compressed air enters into the tire. This procedure keeps the tire air pressure at an appropriate level and increases tire safety. In this study, a regulator was used as a negative-pressure system. A check valve was selected the minute flow check valve depending on the shape of the configured system. In addition, the material of the tube was developed with excellent physical properties and resistances (elastic rebound, working temperature, etc.) owing to its complete compression and restoration. A tube performance tester was developed and a computer aided engineering (CAE) model was modeled for comparison with the test results. Using the tester and model, it was possible to optimize the shape of the tube and regulator. Finally, the reliability of the study was verified through the prototype test. The developed equipment and systems can be used for the manufacture of high-performance and safe tires. 相似文献
197.
Hyung Rim Choi Hyun Soo Kim Byung Joo Park Nam-Kyu Park Sang Wan Lee 《Maritime Policy and Management》2013,40(3):197-210
The major characteristics of ERP (Enterprise Resource Planning) are an enterprise-wide system that covers all the business functions and information resources, integrated database, built-in best industry practice, packaged software and open architecture. ERP enables reduction of system development time, flexibility, standardization of workflow and effective business planning capability. ERP is mainly for the manufacturing industry. However, the principles of ERP can also be applied to container terminal operating systems. This paper presents an ERP system approach for a container terminal. It has clustered the workflow of a container terminal and analysed the business process to generate the best workflows. The integrated database is designed to eliminate redundancy and keep integration. The core of ERP for container terminal is the planning facility such as berth planning and yard planning. The planning capability is very tightly coupled with data flow from client entities such as shipping companies. The ERP can handle the existing problems of container terminal operation that are mainly caused by lack of integration of a whole information resource in a container terminal, ad-hoc and poor planning capability, disconnected and incorrect data from client companies. The ERP approach can not only resolve the problems of container terminals but also promote adoption of information systems for container terminals in the world that have not yet implemented terminal operating systems. 相似文献
198.
This paper proposes an alternative algorithm to solve the median shortest path problem (MSPP) in the planning and design of urban transportation networks. The proposed vector labeling algorithm is based on the labeling of each node in terms of a multiple and conflicting vector of objectives which deletes cyclic, infeasible and extreme-dominated paths in the criteria space imposing cyclic break (CB), path cost constraint (PCC) and access cost parameter (ACP) respectively. The output of the algorithm is a set of Pareto optimal paths (POP) with an objective vector from predetermined origin to destination nodes. Thus, this paper formulates an algorithm to identify a non-inferior solution set of POP based on a non-dominated set of objective vectors that leaves the ultimate decision to decision-makers. A numerical experiment is conducted using an artificial transportation network in order to validate and compare results. Sensitivity analysis has shown that the proposed algorithm is more efficient and advantageous over existing solutions in terms of computing execution time and memory space used. 相似文献
199.
J. Xu Y. B. Li X. Chen D. Y. Ge B. H. Liu M. Y. Zhu T. H. Park 《International Journal of Automotive Technology》2011,12(5):687-695
During accident, the interlayer of windshield plays an important role in the crash safety of automotive and protection of
pedestrian or passenger. The understanding of its energy absorption capability is of fundamental importance. Conventional
interlayer material of automotive windshield is made by Polyvinyl butyral (PVB). Recently, a new candidate of high-performance
nanoporous energy absorption system (NEAS) has been suggested as a candidate for crashworthiness. For the model problem of
pedestrian head impact with windshield, we compare the energy absorption capabilities of PVB and NEAS interlayers, in terms
of the contact force, acceleration, velocity, head injury criteria, and energy absorption ratio, among which results obtained
from PVB interlayers are validated by literature references. The impact speed is obtained from virtual test field in PC-CRASH,
and the impact simulations are carried out using explicit finite element simulations. Both the accident speed and interlayer
thickness are varied to explore their effects. The explicit relationships established among the energy absorption capabilities,
impact speed, and interlayer material/thickness, are useful for safety evaluation as well as automotive design. It is shown
that the NEAS interlayer may absorb more energy than PVB interlayer and it may be a competitive candidate for windshield interlayer. 相似文献
200.
Reliability-based topology optimization based on bidirectional evolutionary structural optimization using multi-objective sensitivity numbers 总被引:1,自引:0,他引:1
K. -H. Cho J. -Y. Park S. -P. Ryu J. -Y. Park S. -Y. Han 《International Journal of Automotive Technology》2011,12(6):849-856
Reliability-based topology optimization (RBTO) is used to obtain an optimal topology satisfying given constraints, as well
as to consider uncertainties in design variables. In this study, RBTO was applied to obtain an optimal topology for the inner
reinforcement of a vehicle’s hood based on bidirectional evolutionary structural optimization (BESO). A multi-objective topology
optimization technique was implemented to obtain the optimal topology for two models with different curvatures while simultaneously
considering the static stiffness of bending, torsion, and natural frequency. A performance measure approach (PMA) with probabilistic
constraints formulated in terms of the reliability index was employed to evaluate the probabilistic constraints. The optimal
topology obtained by RBTO was evaluated and compared to that obtained by deterministic topology optimization (DTO). A more
suitable topology was obtained through RBTO than DTO even though the final volume obtained by RBTO was generally slightly
greater than that obtained by DTO. The multiobjective optimization technique based on BESO can be applied very effectively
with topology optimization for a vehicle’s hood reinforcement. 相似文献