• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.562-574
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• 2012

Simulation validation techniques which have been employed in most studies are statistical analysis, which validate a model with mean or variance of throughput and resource utilization as an evaluation object. However, these methods have not been able to ensure the reliability of individual elements of the model well. To overcome the problem, the weighted F-measure method was proposed, but this technique also had some limitations. First, it is difficult to apply the technique to complex system environment with numerous values of interarrival time because it assigns a class to an individual value of interarrival time. In addition, due to unbounded weights, the value of weighted F-measure has no lower bound, so it is difficult to determine its threshold. Therefore, this paper propose weighted F-measure technique with cluster analysis to solve these problems. The classes for the technique are defined by each cluster, which reduces considerable number of classes and enables to apply the technique to various systems. Moreover, we improved the validation technique in the way of assigning minimum bounded weights without any lack of objectivity.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.139-148
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• 2016

A seasonal outlook for crop insect pests is most valuable when it provides accurate information for timely management decisions. In this study, we investigated probable tele-connections between climatic phenomena and pest infestations in Korea using a statistical method. A rice insect pest, brown planthopper (BPH), was selected because of its migration characteristics, which fits well with the concept of our statistical modelling - utilizing a long-term, multi-regional influence of selected climatic phenomena to predict a dominant biological event at certain time and place. Variables of the seasonal climate forecast from 10 climate models were used as a predictor, and annual infestation area for BPH as a predictand in the statistical analyses. The Moving Window Regression model showed high correlation between the national infestation trends of BPH in South Korea and selected tempo-spatial climatic variables along with its sequential migration path. Overall, the statistical models developed in this study showed a promising predictability for BPH infestation in Korea, although the dynamical relationships between the infestation and selected climatic phenomena need to be further elucidated.

• The Korean Journal of Financial Management
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• v.25 no.2
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• pp.191-213
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• 2008

This study tests and reconfirms the wealth transfer of mergers and acquisitions(M&As) by examining the changes in and the relationship between shareholder and bondholder wealth after the announcements of M&As for the publicly listed firms in Korea Stock Exchange and KOSDAQ market during $1999{\sim}2006$. The change in shareholder wealth is measured by the Cumulative Abnormal Return(CAR) at the M&A announcements, and the change in bondholder wealth is calculated using the Yield Spread Change(YSC) and the change in acquiring firms' credit ratings. The empirical tests show that the CAR of 344 sample acquiring firms at the announcement is 3.59%, which confirms results of the prior research on M&As in Korean market. The average YSC for 35 sample acquiring firms between $2001{\sim}2006$ proves to be negative when we use the yield spread of firms with comparable credit ratings as a benchmark, which means that the acquiring firms' bondholders gain with the announcements of M&As. We find the same result using another benchmark-the yield spread of government bonds. The improvement in the acquiring firms' credit ratings one year after the M&As also indicates that the M&As, on average, increase bondholder wealth. Our test results are consistent with those of the existing studies on the effect of bondholder wealth after the M&As in the United States, which shows that the bondholder wealth increases after the M&As. We do not find the evidence that there is a wealth transfer from the acquiring firms' bondholders to the shareholders after the M&A announcements. Rather, this study confirms that the wealth of the acquiring firms' bondholders increases in the M&As in Korea.

• The Journal of the Korea Contents Association
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• v.11 no.7
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• pp.519-527
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• 2011

The e-Learning program is a multimedia data program consisting of texts, images, animation, audio and video. The development of an e-Learning program requires time and is a complex process, requiring cooperation and open-communication between all parties involved, particularly in the event of a problem. This study will analyze the e-Learning contents development process from the Social Negotiation Perspective. An appropriate process for the development of the program and effective decision-making guidelines for those parties involved will be recommended. Participants' viewpoints regarding program development and guidelines were studied qualitatively, while the evaluation of developed content employed both qualitative and quantitative research. The study found the following results. First, the development of an e-Learning program requires a clear goal and purpose. Second, the target group must be clearly identified. Third, all parties involved must share in the development process and its outcomes. Fourth, the party requesting the program must allocate the appropriate time and budget for the development group. Finally, the project requires a strong, capable leadership for effective decision-making.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3538-3547
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• 2010

As Telepresence has emerged as a key collaboration tool for supporting trade business, the need for using Telepresence has also been increased in the foreign countries. In this context, we has studied an exploratory research to analyze how staffs-in-charges of trade support authority, exhibition & convention center and SME(Small and Medium-Size Enterprise) perceive the general concept of Telepresence, the necessity, feasibility, business values and expected problems of Telepresence's adoption and use. The finding indicated that there seemed to be significant differences between the necessity and the feasibility of Telepresence adoption and use. In addition, they were anticipating some problems when building Telepresence. Major reasons are incompatibility between Telepresence systems, lack of usability and difficulties of fixing a rental fee. The results of the perception analysis also showed that Telepresence would positively influence on creating business value. The analysis revealed that the core factors of the successful adoption and use of Telepresence are stable network environment, awareness and accessability, and education and promotion. Through the perception analysis, I came up with the core factors to implement Telepresence successfully and use it properly. And the fact that I presented the guideline to build Telepresence for SME makes this study meaningful.

• Journal of Intelligence and Information Systems
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• v.11 no.3
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• pp.83-101
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• 2005

Customer retention is one of the major issues in life insurance industry, in which competition is increasingly fierce. There are many things for the life insurers to do many things to retain the customers. One of those things is to make sure to keep in touch with all customers. When an insurance-planner resigned, his/her customers must be taken care of by some planner-assistants. This article outlines the design of Contact Scheduling System (CSS) that supports planner-assistants for contacting the customers. Planner-assistants are unable to share the resigned insurance-planner's experience and knowledge regarding the customer relationship management. The CSS developed by employing both Classification And Regression Tree (CART) technique and Sequential Pattern Mining (SPM) technique has a two-stage process. In the first stage, it segments the customers into eight groups by CART model. Then it generates contact scheduling information consisting of contact-purpose, contact-interval and contact-channel, according to the segment's typical contact pattern. Contact-purpose is derived by schedule-driven, event-driven, or business-rule-driven. Schedule-driven contact is determined by SPM model. In the operation of CSS in a realistic situation, it shows a practicality in supporting planner-assistants to keep in touch with the customers efficiently and effectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.446-452
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• 2020

As the use of children's school buses increases, accidents caused by the negligence of school bus drivers and ride carers have also increased significantly. To prevent such accidents, the government is coming up with various policies. We propose an accident prevention and safety management system for children's school buses. Through this system, bus drivers can easily check whether each child is seated and whether the seat belt is used, so it is possible to quickly respond to children's conditions while driving. With the ability to recognize faces by analyzing camera images, children can use a seat belt that is automatically adjusted to their height. It is therefore possible to prevent secondary injuries that may occur in the event of a traffic accident. In addition, a sleeping child-check system is provided to confirm that all children get off the bus, and a text service is provided to inform parents of their children's locations in real time. Based on Raspberry Pi, the system is implemented with cameras, pressure sensors, motors, Bluetooth modules, and so on. This proposed system was attached to a bus model to confirm that the series of functions work correctly.

• Journal of the Korean Society for information Management
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• v.27 no.3
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• pp.15-34
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• 2010

In this study we determine the level of awareness among academic librarians of ten technological tools as outlined in American Libraries. Towards this end, we conducted a survey targeting 156 academic librarians in 25 Korean university libraries. Questionnaires were designed to determine both the viability and level of acceptance of the ten technological proposals in question. Conclusions drawn after analyzing the responses to the survey were as follows: 1) Customer service can be improved by first drawing up a list of technological skills required for staff members. Methods to develop the cataloging service to more closely match individual user preferences and the use of SMS to send alerts proved to be the proposals, of the ten that were proposed, that not only bore the greatest necessity but also proved to be the most effective once they were implemented. 2) Proposals that proved to be the most difficult to implement were: Using technology to improve the cataloging service to make it more capable of evolving according to the individual preferences of users; the special event wiki for users; and improvements in customer service arising from identifying and drawing up a list of technological skills required for staff members.

• Korean Journal of Psychosomatic Medicine
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• v.18 no.2
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• pp.72-81
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• 2010

Objectives : Early detection and proper management of distress are known to be important for efficient care in cancer patients. The aim of this study was to investigate the prevalence of distress and to evaluate its influence on quality of life in subjects with breast cancer. Methods : A total of 95 patients were recruited from a breast cancer patient community of a general hospital in Seoul. The Hospital Anxiety and Depression Scale(HADS), the Insomnia Severity Index(ISI), the Impact of Event Scale-Revised(IES-R) and the Functional Assessment of Cancer Therapy-Breast(FACT-B) were measured. Results : The prevalence of anxiety, depression, insomnia and posttraumatic stress disorder symptom among breast cancer patients was 26.3%, 26.3%, 13.7%, 24.3%, respectively. Nearly half(47.4%) of total subjects were under one or more significant distress, and they showed significantly lower mean FACT-B total score than patients without distress(82.91 vs. 107.20, p<0.001). Distress was negatively correlated with the quality of life to a significant level even in patients who were in normal range of distress scale scores. Conclusion : These results support the importance of regular screening and proper management of distress for breast cancer patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.489-498
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• 2018

The purpose of this study is to examine whether there is a difference in the awareness of death based on happiness (since attitude or way of life differs among the general public, depending on the perception of death), and to investigate whether there is a difference in the interest in hospices between a group with a high happiness index and a group with a low happiness index. A survey was conducted on 200 men and women aged over 20 who participated in a walking event held in a metropolitan city on April 22, 2017. The survey consisted of eight demographic items: gender, age, education, occupation, marital status, family cohabitation, religion, and health status. It included 29 questions regarding happiness and nine questions regarding the perception of death. For the statistical tests, a chi-square test, an independent sample t-test, correlation analysis, and canonical correlation analysis were performed on the items of the survey based on a happiness index. The results of the study showed that, for a suitable place for death, medical institutions was the highest score (46.3%) for the group with a low happiness index, and own house was highest (59.4%) for the group with a high happiness index. This was a significant difference. It is thought that management systems should be supplemented by professional manpower, educating people so as to increase the utilization rates of home-based hospice as a way for patients to die in a comfortable and familiar place because, for Korea, death is much more common in hospitals. It is also necessary to increase the awareness of death and to make effective use of hospices through individual and various other approaches, considering the demographics of the subjects.