• Korean Journal of Mathematics
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• v.29 no.2
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• pp.371-386
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• 2021

This paper investigates two discrete time queueing inventory models with positive service time and lead time. Customers arrive according to a Bernoulli process and service time and lead time follow geometric distributions. The first model under discussion based on replenishment of order upto S policy where as the second model is based on order placement by a fixed quantity Q, where Q = S - s, whenever the inventory level falls to s. We analyse this queueing systems using the matrix geometric method and derive an explicit expression for the stability condition. We obtain the steady-state behaviour of these systems and several system performance measures. The influence of various parameters on the systems performance measures and comparison on the cost analysis are also discussed through numerical example.

• ETRI Journal
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• v.44 no.2
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• pp.346-354
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• 2022

The SYN flooding attack is widely used in cyber attacks because it paralyzes the network by causing the system and bandwidth resources to be exhausted. This paper proposed a self-information approach for detecting the SYN flooding attack and provided a detection algorithm with a hierarchical policy on a detection time domain. Compared with other detection methods of entropy measurement, the proposed approach is more efficient in detecting the SYN flooding attack, providing low misjudgment, hierarchical detection policy, and low time complexity. Furthermore, we proposed a detection algorithm with limiting system resources. Thus, the time complexity of our approach is only (log n) with lower time complexity and misjudgment rate than other approaches. Therefore, the approach can detect the denial-of-service/distributed denial-of-service attacks and prevent SYN flooding attacks.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.939-942
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• 2008

In this study, some useful implications related to mobile RFID service will be given to the mobile communication service providers and staff in charge through developing and assessing the evaluation dimensions considering quality, value, and customer's satisfaction, complaint and loyalty in mobile RFID service which is in trial service stage. For this purpose, web based survey was performed for general customers who had experienced mobile RFID trial service, 350 pieces of collected samples were analyzed, mobile RFID service was assessed with the tool of SPSS 12.0k, and the difference to customers' characteristic was analyzed. On the basis of the result through the empirical research, before commercial launch, serviceable implications such as service improvements which can be obtained through the evaluation result of mobile RFID service were provided for the staff and the managers in charge of mobile communication service.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5564-5577
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• 2014

This study examined how the differences in household characteristics influence consumer expenditure patterns. The Price-Scaling AIDS model with household income and expenditure survey data were used for the analysis. The results showed that the income elasticity of the service items is greater than non-service items, indicating an increase in higher demand of service items with the same increase in household income. The household expenditure patterns vary according to the commodities, holding age and income level. The so-called traditional pattern, which emphasizes spending for non-service items, changed to the one with a higher expenditure ratio for service items. Such a change in household expenditure patterns naturally derives the expansion of the relevant service market; hence, the growth of the related service industry. This highlights the need to formulate an appropriate response from the supply side that deals with the changes in the service market.

• Health Policy and Management
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• v.24 no.4
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• pp.367-379
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• 2014

Background: Over the last decade, medical tourism industry has grown in Korea. Especially the number of Mongolian medical tourists has increased rapidly. Therefore, the Mongolia is one of the targets for Korea medical tourism. The purpose of this study is to investigate the effects of destination image and expected attributes of medical services on Mongolian's intention to use Korean medical tourism service. Methods: This study empirically collected survey data from Mongolian lived in Mongolia. The study analyzed the data using a PLS model. Results: Our results are as follows. First, the country image didn't significantly have causal effects on expected medical service quality and perceived risk. Second, tourism image (e.g., entertainment, economic feasibility, and local convenience) has significantly causal effects on expected medical service quality and perceived risk. However, tourist site as tourism image didn't significantly have causal effects on expected medical service quality and perceived risk. Third, medical image made a statistically significant effect on expected medical service quality and perceived risk. Fourth, the expected medical service quality showed a significant effect on intention to use Korean medical tourism service. Fifth, the perceived risk of medical tourism showed a significant effect on the reliability of medical tourism, but didn't show a significant effect on the intention to use Korean medical tourism service. Finally, the reliability has a significant effect on the intention to use Korean medical tourism service. Conclusion: From our empirical results, this study concluded that as a strategy attracting Mongolian patients, it is more effective to strengthen Korean hospital image and tourism image than Korean country image.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.387-410
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• 2013

Due to the development of information technology, Convergence and Creative Economy became hot issues. For example, products become more intelligent and services are likely to be connected and integrated around core services or provided as bundle solution. Meanwhile products and services are integrated in the context of mutual supplementation, which leads to Servitization of Products and Productization of Services in many industries. Previous studies have addressed Convergence with different terms and definitions such as Convergent, Multicategory Multifunctional Product, Clouding Service, Bundle and so on from one perspective such as consumers, suppliers or technology according to a wide range of academic approaches. Thus, this study attempted to suggest the most typical convergence products released in the convergence environment and categorize those products. Furthermore, this study has pointed out the problems in the New Product Development Framework discussed in the studies on marketing by taking the situation of the public sector into account and then suggested "New Service Development Framework in the Public Sector" that are different from traditional e-Gov. approach basically and will enable the government to create public information service and provide them to enterprises or citizens. It also emphasized the importance of Business Conceptualization Stage in the framework; argued that there is a necessity of an integrative study from the perspective of technology on the basis of the approach from the perspective of marketing and Policy such as a study of consumer behaviors, design and marketing channel and Policy Integration for the development and dissipation; and furthermore suggested the cases-the development/Diffusion of Transportation Card Service in Seoul and CFC (Call for Collaboration) in Singapore-in order to verify the framework. There is a need to supplement New Service Development Framework so it is able to reflect the distinct characteristics of the public sector from the academic perspective and be used as practical guidelines for SI (System Integration) business to shift into IT Service business. Last but not the least, this study has suggested the limitations and the directions for the future studies.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.3
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• pp.355-365
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• 2009

The purpose of this study was to investigate the effects of cognitive age on service quality, consumer satisfaction, and repurchase intentions across the elderly's lifestyle types in the apparel store. Data were obtained from 853 women in the 50's and 60's living in Busan, and were analyzed by factor analysis, Cronbach's alpha, cluster analysis, one-way ANOVA, Duncan test, and path analysis using SPSS WIN 12.0 and LISREL 8.53. The results showed that the lifestyle of elderly consumers was classified into three factors, such as Active self-fidelitist, Economy family-oriented, and Passive-stagnant. Service qualities perceived by the elderly in apparel stores were composed of Personal Service, Facilities Service, Product Service, and Policy Service. Generally, the younger cognized their ages most of the elderly were the more importantly perceived store service quality, the greater satisfied with apparel store services, and the more intended to repurchase apparels at a store. However, economic family-oriented elderlys were the younger cognized their ages, the less satisfied with the apparel service. Additionally, personal and policy services of the apparel store were important variables for elderlys' satisfaction with store services. The findings provide potential explanations and managerial implications for the elderly market.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.55-68
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• 2016

Academic research of the social service delivery system is very limited. This paper checked on the status of research on current social service delivery system in order to explore new research and policy directions. Analysis study consisted of 79 pieces and the framework was divided into dimensional analysis, content analysis and analytical standards. Research on the papers of social service delivery systems showed from the initial stage of the policy discussion to the phase of the individual services. Summarizing the study is as follows. First, This studies confirmed that at this time the quality studies on social service delivery system is needed. Second, this indicates that right now, the government budget of social services and the data relating to social service agencies will be opened to the public for the expansion of social services studies. Third, to expand social services delivery systems research, it showed that social services demand forecasting research such as budget allocation, population characteristics, equality of public service and local information is needed. Finally, since the quality of service is reduced by the oversupply, the discussion of the entry regulations of social service providers is required.

• International Commerce and Information Review
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• v.16 no.2
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• pp.113-129
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• 2014

The present study attempted to test the effects of using external knowledge services on corporate management performance among SMEs. A survey of SMEs that had used external knowledge services was conducted for the analysis. The findings are as follows. First, regarding government-supported knowledge services for SMEs, knowledge service expert groups' competencies and government's support policies had positive effects on the quality of knowledge services. In particular, the knowledge service expert groups' competencies had more significant effects on the quality of knowledge services than the government's support policies. Second, the quality of knowledge services had significantly positive effects on management performance, whilst confidence-related knowledge service quality factors exerted significant effects on enhancing the relationship with customers and the informationization of knowledge. These findings have the following implication and meaning. The present findings indicate that the government's policy to foster and lay the foundation for knowledge service industry should be furthered, e. g. knowledge service supports for individual companies including knowledge service support projects and systems for SMEs and institutional supports for knowledge service companies and expert groups. In sum, this study is meaningful in that it suggests an effective and efficient policy direction for government's knowledge service provision projects.

• 한국사회정책
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• v.25 no.1
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• pp.125-159
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• 2018

The purpose of this study is to analyze the factors affecting service use intention of long-term care among the disabled. This study conducts a longitudinal study using the modified Andersen model by the disabled age groups of the 50-64 group and the 65 over group. This study examined random effects panel logit analysis for the 50-64 group and the 65 over group by age variations. The results have shown that there are different factors Influencing factors for each specific age group of the disabled(50-64, 65 over). The results were as follows: there are differences of factors between the 50-64 group and the 65 over group. This study found that predisposing factors of the service use intention of long-term care were significantly related to age, residential area, education status, existence of spouses. Enabling factors of the service use intention of long-term care were significantly related to long-term care service recognition, saving, personal salary income level, housing status. Need factors of the service use intention of long-term care were significantly related to chronic diseases, psychological health, IADL. So, there are a need for a policy considerations such as service for the mid-old age disabled by age groups. Finally, implications and future research directions were discussed based on the finding of the study.