• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12A
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• pp.1246-1252
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• 2006

In this paper, a collision probability, processing time and traffic capacity analysis algorithm for RFID system using random FHSS and synchronous FHSS is proposed. Service time, duty cycle, traffic intensity and additional delay time required for re-transmission due to collision are considered and the processing delay and frequency channel capacity are analyzed for the steady state operation of the system. The simulation results which show maximum capacity of the system and explain the accuracy of the algorithm are provided.

• Journal of Ocean Engineering and Technology
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• v.16 no.5
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• pp.80-87
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• 2002

In this study, CT specimens were prepared from spring steel(SUP9) which was used in suspension of automobile for room temperature and low temperature service. We got the following characteristics from fatigue crack growth test carried out in the environment of room temperature and low temperature at $25^{\circ}C$, ­3$0^{\circ}C$, ­5$0^{\circ}C$, ­7$0^{\circ}C$ and ­10$0^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range ΔK in the stable of fatigue crack growth (Region II) was decreased in proportion to descend temperature. It is assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

• Proceedings of the CALSEC Conference
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• 2005.03a
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• pp.163-168
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• 2005

While the client-vendor relationship has been mainly examined from the service receiver's perspective in IS outsourcing literature, the vendor's factors have seldom been explored. To address this issue, our study adopts interaction process theory and develops the model focusing on the competence of the vendor as a key antecedent of the client-vendor relationship intensity and outsourcing success. Results from empirical data gathered from Korean firms indicate that the vendor competence factors identified in this paper positively impacts the client-vendor relationship and outsourcing success. The findings have significant implications for IS outsourcing practices and further research.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.120-128
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• 1995

The fatigue failure of rail is a principal source of derailment accidents. The reduction of fatigue failures can be achieved by Intensive track maintenance and periodic safety assessments for the railway. For the safety assessments, it is required to have more accurate knowledge for fatigue behavior such as the crack initiation, propagation, crack growth rate and the remaining service life in rail. In this paper, the mean stress effects for the fatigue behavior of rail steel are studied. For this study, the fatigue test is conducted and some equations for fatigue evaluation are applied and compared. From the results, we can see that the fatigue crack growth rate is the more increased as the men stress Is the more increased, the mean stress effect is represented well by the combination of stress intensity factor range and maximum stress intensity factor and Crooker and Range's equation represented by ${\Delta}K, K_{max}$ is the best fit for fatigue evaluation and safety assessment of rail.

• Journal of Industrial Convergence
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• v.1 no.2
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• pp.53-67
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• 2003

This paper intends to contribute to the understanding of customer repurchase by studying the relationship between correction of postpurchase dissonance and intention of customer repurchase. Previous studies have broadly speculated on the relationship between the intensity of dissatisfaction and repurchase; few empirical results have, however, been reported. This study is based on a convenience sample of 257individuals who reported intensity of dissatisfaction and type of responses to dissatisfying retailing service situations. The results of an empirical study, the relationship is found between correction of postpurchase dissonance and intention of customer repurchase. And it examines the relatively important marketing factors influencing customer repurchase.

• Journal of applied mathematics & informatics
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• v.39 no.1_2
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• pp.31-43
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• 2021

A homogeneous circular disk undergoing a contact force is considered to investigate the thermo-elastic characteristics, and the inquiry is based on the variations of outer surface temperature and angular velocity. The intensity of stresses grows with the increase of outer surface temperature, and the circumferential strain reacts more sensitively to the change of outer surface temperature than the radial strain. In general, higher angular velocity produces; (i) larger expansion in the radial direction, (ii) smaller displacement in the circumferential, (iii) diminished intensity in the stresses. It is demonstrated that outer surface temperature and angular velocity are critical factors in the determination of thermo-elastic characteristics of homogeneous circular disks subjecting to a contact force. The results obtained can be applied on the design of a homogeneous circular cutter to promote proper and reliable thermos-elastic characteristics in service by the proper operation of these parameters.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.10
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• pp.159-186
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• 1999

This study attempted to present the ways of improving relationship marketing activities of tourist hotels. The field survey was carried out at six deluxe hotels in Seoul to find out their relationship marketing activities and analyze the problems of the activities. The problems were analyzed as follow; 1) lack of adequate understanding of the importance of relationship marketing, 2) poor contents of customer file information, 3) insufficient service encounter management, 4) negative inducement of guests' complaints, 5) insufficient survey of guests' satisfaction, 6) insufficient relationship maintenance programs and regaining program of lost guests. This study relationship marketing activities should be improved with customer information file establishment, service encounter mangement, and communication enforcement as follow; 1. Customer Information File Establishment As relationship marketing Is marketing for individual, it needs customer file information. The guest information files should be made in detail in all the market segments. Hotels have to make use of the information strategically for establishing relationship with their guests. 2. Service Encounter Mnagement Because the guest-oriented mind and professionalism of hotel staff are prerequisite for relationship continuity, hotel should make efforts to make its staff keep the mind and cultivate expert service technique of the staff. 3. Communication Enforcement Communication enforcement consists of communication activities and communication programs which are focused on contact intensity and two-way communication.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.263-271
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• 2011

This study was performed to develop duck stock using various nutritional elements in duck bone by the addition of malic acid (0.5%, 1.0%, 1.5% and 2.0%). Moisture contents, b value, and pH were decreased, while the L value, a value, salinity, and sugar contents were increased by increasing the ratio of malic acid. Thirty four types of free amino acid were detected, and the highest individual amino acid content was 1.0%. In a test for different attributes, malic acid content significantly affected properties including color intensity, transparency, acid flavor, savory flavor, acid taste, and savory taste. In the acceptance test, a malic content of 1.0% was preferred for appearance, taste, and overall quality. The optimal malic acid content for maximizing the overall quality of duck stock was 1.0%.

• Journal of the Optical Society of Korea
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• v.20 no.6
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• pp.704-715
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• 2016

In this paper, we explore a low-complex bandwidth allocation (BA) scheme with multi-level service guarantees in VLC-OFDM systems. Effective capacity theory, which evaluates wireless channel capacity from a novel view, is utilized to model the system capacity under delay QoS constraints of the link layer. Since intensity modulation of light is used in the system, problems caused by frequency selectivity can be neglected. Then, the BA problem can be formulated as an integer programming problem and it is further relaxed and transformed into a concave one. Lagrangian formulation is used to reformulate the concave problem. Considering the inefficiency of traditional gradient-based schemes and the demand for distributed implementation in local area networks, we localize the global parameters and propose a quasi-distributed quadratic allocation algorithm to provide two-level service guarantees, the first level is QoS oriented, and the second level is QoE oriented. Simulations have shown the efficient performance of the proposed algorithm. The users with more stringent QoS requirements require more subcarriers to guarantee their statistical delay QoS requirements. We also analyze the effect of subcarrier granularity on the aggregate effective capacity via simulations.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.525-532
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• 2009

The purpose of this study was to compare the ability of Northeast Asians to discriminate the salinity in salt solution and foods, and to compare their preference of salinity. Panels of Korean, Japanese and Chinese evaluated three kinds of samples that contained different level of salt such as salt solutions, julienned radish salad, Bulgogi. The salt levels had been manipulated to produce five samples of each one. The salt solutions were prepared by adding 0.3%, 0.7%, 1.1%, 1.5%, 1.9% salt into water. Different levels of salt in Julienned radish salad and Bulgogi were prepared by adding 0.5%, 1.5%, 2.5%, 3.5%, 4.5% salt to the recipe. The results of this study showed that the three ethnic groups had significant differences in their ability to distinguish the intensity of salinity in solutions containing a high contents of salt(1.5~1.9%). According to the regression analysis, Koreans(a=1.050) turned out to be the most able to detect the intensity of salinity, compared to the Japanese (a=0.988) and Chinese (a=0.807). All ethnic groups preferred a salt concentration of 0.3%, and the preference for this concentration was lower in Japanese than in Koreans and Chinese. There were significant differences in the perception of salinity in the julienned radish salad containing more than 3.5% salt between Koreans and Chinese. Koreans (a=1.168) appeared to be the most able to detect the intensity of salinity, compared to the Japanese (a=0.908) and Chinese (a=0.793). Both Koreans and Japanese had the strongest preference for the julienned radish salad containing a 1.5% salt concentration, while the Chinese preferred a salt concentraion of 2.5%. The ability of ethnic groups to detect the salinity in Bulgogi were significantly different at high salt -concentrations (more than 3.5%), and the awareness of salinity was as fallows : Koreans(a=0.161) > Japanese (a=0.896) > Chinese (a= 0.845). Koreans and Japanese had a higher preference or the Bulgogi containing a salt concentration of 1.5%, and the Chinese had higher preference at a salt concentration of 2.5%.