• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.103-114
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• 2006

Now distribution centers include an ASRS (Automated Storage and Retrieving System) and automated transfer systems such as conveyors and AGV (Automated Guided Vehicle). These automated distribution centers have lots of parameters to be considered fur operating performance. The general basic parameters in the distribution centers are specifications of storage equipment, system operating rules, configuration of storage area and unit load features. In this paper, an approach using simulation and metamodeling with response Surface method to optimize the design parameters of an automated distribution center model is presented. The simulation based metamodel will constitute an efficient approximation of the system function, and the approximate function will be used to design rapid optimal parameters of the distribution center model. This paper provides a comprehensive framework for economical material flow system design using the simulation and metamodeling.

• Journal of the Korea Society for Simulation
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• v.9 no.3
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• pp.91-102
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• 2000

The distribution routing problem is one of the important problems in distribution and supply center management. This research is concerned with an integrated distribution routing problem for multi-supply centers based on improved genetic algorithm and GUI-type programming. In this research, we used a three-step approach; in step 1 a sector clustering model is developed to transfer the multi-supply center problem to single supply center problems which are more easy to be solved, in step 2 we developed a vehicle routing model with time and vehicle capacity constraints and in step 3, we developed a GA-TSP model which can improve the vehicle routing schedules by simulation. For the computational purpose, we developed a GUI-type computer program according to the proposed methods and the sample outputs show that the proposed method is very effective on a set of standard test problems, and it could be potentially useful in solving the distribution routing problems in multi-supply center problem.

• Journal of Distribution Science
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• v.11 no.10
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• pp.17-25
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• 2013

Purpose - This study analyzes the effect of customers' perceived service innovativeness of service centers for electronic goods, on repurchase intentions of customers, using behavior intentions of service centers as a mediator variable. In customer management and customer relationship marketing, service centers can be the most representative customer relationship management departments because they are most closely placed at the interface with customers. In addition, this study intends to investigate if continuous relationship with customers during one-time product-selling can affect their repurchase intentions. Specifically, this research aims to investigate if the expansion of the saturated physical market of the manufacturing business, to intangible service markets, can be competitive enough to satisfy customer needs. Research design, data, and methodology - This study targets college students, and especially those who have computers, digital cameras, or cell-phones, and often use electronic products and services. In order to investigate our hypothesis, we analyzed dates through SEM (structural equation modeling) using SPSS for Windows 18.0 and AMOS 18.0. In addition, we measured Cronbach's α coefficient using SPSS for Windows 18.0 in order to measure reliability. Further, using AMOS 18.0, this research statistically measured convergent validity as well as discriminant validity, and examined mediation models and path models in which service innovativeness leads to customers' repurchase intentions of electronic products. Results - As a result, this research shows that customers' perceived service innovativeness of service centers for electronic goods has significant positive influence on customers' behavior intentions of service centers. In addition, service innovativeness of electronic goods' service centers also has significant positive influence on repurchase intentions of customers. Conclusion - This study investigates the effect of customers' positive relation with the innovativeness of electronic service center on their behavior intention and product repurchase. The more concrete, important results of the study are as follows. Through the mediating effect, the findings of the study suggest that customers' behavior intentions of service centers partially mediate the effect of customers'perceived service innovativeness of service centers for electronic goods on customers' repurchase intentions. This research also provides an insight that the importance of service innovativeness and innovative approaches in managing customers should be recognized in the process of repurchase and service roles of manufacturing business as a way for customer management. As a result, the relationship between customer satisfaction and service quality of service centers for the electronic products is very sensitive. Although previous studies focus on certain aspects of the case for enhancing service innovation (Kim, 2012), this research recommends that the service centers need to understand the customers'desire first and try to adapt to achieve customer satisfaction by being innovative. This innovativeness of service centers would make customers visit them consistently, which in the long run, will also influence their repurchase decisions.

• Journal of the Optical Society of Korea
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• v.18 no.4
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• pp.317-329
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• 2014

In vision measurement systems based on structured light, the key point of detection precision is to determine accurately the central position of the projected laser line in the image. The purpose of this research is to extract laser line centers based on a decision function generated to distinguish the real centers from candidate points with a high recognition rate. First, preprocessing of an image adopting a difference image method is conducted to realize image segmentation of the laser line. Second, the feature points in an integral pixel level are selected as the initiating light line centers by the eigenvalues of the Hessian matrix. Third, according to the light intensity distribution of a laser line obeying a Gaussian distribution in transverse section and a constant distribution in longitudinal section, a normalized model of Hessian matrix eigenvalues for the candidate centers of the laser line is presented to balance reasonably the two eigenvalues that indicate the variation tendencies of the second-order partial derivatives of the Gaussian function and constant function, respectively. The proposed model integrates a Gaussian recognition function and a sinusoidal recognition function. The Gaussian recognition function estimates the characteristic that one eigenvalue approaches zero, and enhances the sensitivity of the decision function to that characteristic, which corresponds to the longitudinal direction of the laser line. The sinusoidal recognition function evaluates the feature that the other eigenvalue is negative with a large absolute value, making the decision function more sensitive to that feature, which is related to the transverse direction of the laser line. In the proposed model the decision function is weighted for higher values to the real centers synthetically, considering the properties in the longitudinal and transverse directions of the laser line. Moreover, this method provides a decision value from 0 to 1 for arbitrary candidate centers, which yields a normalized measure for different laser lines in different images. The normalized results of pixels close to 1 are determined to be the real centers by progressive scanning of the image columns. Finally, the zero point of a second-order Taylor expansion in the eigenvector's direction is employed to refine further the extraction results of the central points at the subpixel level. The experimental results show that the method based on this normalization model accurately extracts the coordinates of laser line centers and obtains a higher recognition rate in two group experiments.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.79.4-80
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• 2021

Sunspots' subsurface structure is an important subject to explain their stability and energy transport. Previous studies suggested two models for the subsurface structure of sunspots: monolithic model and cluster model. However, it is not revealed which model is more plausible so far. We obtain clues about the subsurface structure of sunspots by analyzing the motion of umbral flashes observed by the IRIS Mg II 2796Å slit-jaw images (SJI). The umbral flashes are believed as shock phenomena developed from upward propagating slow magnetohydrodynamic (MHD) waves. If the MHD waves are generated by convective motion below sunspots, the apparent origin of the umbral flashes known as oscillation center will indicate the horizontal position of convection cells. Thus, the distribution of the oscillation centers is useful to investigate the subsurface structure of sunspots. We analyze the spatial distribution of oscillation centers in the merged sunspot. As a result, we found that the oscillation centers distributed over the whole umbra regardless of the convergent interface between two merged sunspots. It implies that the subsurface structure of the sunspot is not much different from the convergent interface, and supports that many field-free gaps may exist below the umbra as the cluster model expected. For more concrete results, we should confirm that the oscillation centers determined by the umbral flashes accurately reflect the position of wave sources.

• Journal of the Korean association of regional geographers
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• v.13 no.5
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• pp.576-594
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• 2007

The purpose of this study is to derive policy implications in allocating day care centers for the elderly with more efficiency and/or equity by calculating and analysing the accessibility scores of individual dongs to day care centers for the elderly in Seoul using GIS spatial analysis techniques. The study finds that the spatial distribution of the centers does not respond to the distribution of the potential users very well and that dongs in Gangseo-gu and Songpa-gu at the outskirt of Seoul has the lowest level of accessibility. The findings of the study has policy implications in the management of day care centers for the elderly. First, in order to improve the accessibility of the elderly to the centers, an increase in the number and the capacity of the centers needs to be made especially in areas with lower level of services provided. Second, if policy decision is made in the way to increase the capacity of the existing centers rather than to increase the number of centers due to, for example, the budget limit, capacity expansion needs to be made in the centers with higher proximity in order for more elderly people to use the centers more frequently with easy access. Finally, this type of accessibility analysis techniques needs to be used to allocate, expand, and evaluate other types of care facilities for the elderly and social welfare facilities in order to preserve the welfare right of the users of the facility who usually have a lower mobility and to assure the necessity of the resource investment.

• Korean Journal of Community Nutrition
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• v.6 no.1
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• pp.91-96
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• 2001

The purpose of this study was to identify the determinants of nutrition service utilization in health centers. Utilization of nutrition services for chronic discase were also investigated. Interview survey using questionnaire was conducted to collect the data required for analysis. The study subjects were 300 residents over 40 years of age, and 15 health workers representing health center service personnel in Kypnggi province. A wilcoxon 2-sample test and Kruskal-Wallis test were used to compare the distribution of health centers by health center characteristics and nutrition services. A chi-square test was used to test the association between service utilization and personal variables of the population. A multiple logistic regression analysis was used to measure the relative importance between the variables on service utilization. The results showed that only 10.0% of the study subjects used nutrition services provided by the health centers. Pilot project implementation and location of health centers, as well as educational level of the residents were significant factors influencing the utilization of the nutrition services provided by the health centers. Among the variables, pilot project implementation was the most important factor that influenced the nutrition service utilization in health centers.

• The Mathematical Education
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• v.29 no.2
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• pp.79-93
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• 1990

In this thesis the following studies have been tried: 1. To estimate reliability and validity of the items of scholastic achievment tests that had been tested by the evaluation service centers. 2. To smooth the sample frequency distribution of observed scores and to estimate the frequency distribution of observed scores approximating to the Negative Hypergeometric Distribution.

• Journal of Distribution Science
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• v.8 no.4
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• pp.35-41
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• 2010

Although dictionary definition of standardization is 'to prevent disordered complexity and to make and use rules for reasonable simplification or unification, from a position of shop-floor operations of distribution, it is directly connected to efficiency, that is 'productivity equals cost savings'. This study analyzed influence of standardization of agricultural product packages in hypermarkets on costs in stakeholders of distribution channel such as suppliers, distribution centers and hypermarkets. The research findings demonstrated that it would influence manufacturing costs of suppliers and improve shop productivity of hypermarkets.

• Journal of Distribution Science
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• v.13 no.10
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• pp.83-91
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• 2015

Purpose - The purpose of this study is to identify whether the operation of cultural centers in discount stores contributes to their profitability. Thus, this study is aimed at exploring how the lifestyles of customers who use the cultural centers influence their intention to use the discount stores. Specifically, the effect of shopping value on the correlation between the lifestyle types and usage intention of the customers were examined through a structured research model. To verify the effect, a survey on 139 customers of the Cultural Center of Nonghyup Hanaro Club's S branch was conducted and the valid questionnaires were used for analysis. Research design, data, and methodology - The findings are as follows. First, the lifestyles seeking self-realization had a positive effect on utilitarian value, and lifestyles seeking pop cultures had a positive effect on hedonic value. Second, the mediating effect of shopping value on the correlation between the lifestyle types and usage intention of the customers is as follows. Utilitarian value had a mediating effect only on the lifestyles seeking self-realization. In case of lifestyles seeking pop cultures, the use of Cultural Center had no effect on the intention to use the discount store. Third, an analysis of a revised research model revealed that the store usage intention of lifestyles seeking pop cultures can be enhanced by boosting the utilitarian value through hedonic value. Results - The findings suggest the following. Customers with lifestyles seeking self-realization, who value what is beneficial to them with little attention to the perceptions of others, are highly interested in the benefits they can gain from shopping. As for customers with lifestyles seeking pop cultures, they are highly likely to consume products popular in a particular culture such as new products and sports, based on financial stability they pursue. Thus, they prefer more subjective, personal experience, unlike consumers pursuing utilitarian value. Conclusions - As a result, the former pursues hedonic value gained in the process of shopping with fun and joy, rather than doing shopping with a particular purpose in mind. Therefore, Cultural Centers need to offer information that fits the lifestyles of the users so that they are more likely to use the discount stores. However, if the Cultural Centers offer unified, profit-driven products and information, just to increase their store sales, it can backfire, which occurred in the past. On the other hand, if they provide information that fits the lifestyles of the users, it can actually increase the sales. Also, the findings suggest that sophisticated marketing strategies that can boost the hedonic value of customers by linking the educational contents of Cultural Centers to actual shopping, which is beneficial to consumers, should be set and operated by discount stores. In particular, customers with lifestyles seeking self-realization can be encouraged to use the stores by making them recognize the utilitarian value. However, the use of Cultural Centers doesn't necessarily lead to higher sales among customers with lifestyles seeking pop cultures. As mentioned previously, unified marketing strategy is not as effective for Cultural Centers of large discount stores.