• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.87-95
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• 2001

In Production system, there are two ; One is the JIT system, which was developed by the Toyota corporation : the other is the MRP system, which was developed in the United States. The JIT system has been proved its effectiveness for production management system by many industries, however the effectiveness of its application in non-repetitive productions is yet uncertain unlike the MRP system. There has been many efforts in comparing and analyzing the usefulness and the limitation of those production systems. Accordingly, this study has focused its simulation model using MRP and JIT.

• The Korean Journal of Health Service Management
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• v.7 no.3
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• pp.275-286
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• 2013

To identify the prevalence and its influencing factors on depression among elderly vulnerable people in one urban community. This study used data from 381 of elderly vulnerable people in the community. The prevalence of depression was found to be 51.97%. Multivariate logistic regression analysis shows that depression was more prevalent as people in female gender; people with lower self-esteem compared to those with higher self-esteem; in elderly who perceived lower social support compared to those who perceived higher social support; and in the older adults with limitation in instrumental activity of daily living. The finding of a significant association between gender difference; self-esteem; perceived social support, and limitation in instrumental activity of daily living and occurrence of depression expected to promote the screening strategy for elderly at risk of depression in Korean community.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.881-885
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• 2005

Scheduling repetitive projects under limitations on the amounts of available resources (labor and equipment) has been an active subject because of its practical relevance. Traditionally, the limitation is specified as a deterministic (fixed) number, such as 1000 labor-hours. The limitation, however, is often exposed to uncertainty and variability, especially when the project is lengthy. This paper presents a stochastic optimization model to treat the situations where the limitations of resources are expressed as probability functions in lieu of deterministic numbers. The proposed model transfers each deterministic resource constraint into a corresponding stochastic one and then solves the problem by the use of a chance-constrained programming technique. The solution is validated by comparison with simulation results to show that it can satisfy the resource constraints with a probability beyond the desired confidence level.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.39
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• pp.345-366
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• 2008

The paper analyzes GMO legal system and the problems of its management in China and their suggestions to Korea. GMO has been arising as a principal alternative of grain while grain prices continue to climb. Although there has been concerns about GMO imported from China, it is true that we have not studied on China's legal system and the problems of its management in China. The paper believes that when Chinese government does not manage GMO primarily, we have a high possibility that China's GMO food will access to Korean market at any time, and threaten our health and safety. Hence, it is highly time to analyze how legally China treats GMO and what the problems of its management are. The paper found out problems of China's GMO management in three ways. Firstly, GMO legal system of China is confused and it has limitation of effectiveness. China has no regulations like "a law" to regulate GMO and regulations which exists now are not easy to apply in substance. Secondly, China has no administrative strictness to manage GMO. For example, the regulation which ministry of agriculture in China promulgated in March of 2002 started to use partially since 2003, 7. Thirdly, China, as a nation that administration superiors to, market does not do its roll to control GMO. It relates to the low concerns and care of Chines people about GMO. The paper shows suggestions and countermeasures according to problems of China's GMO management.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.215-217
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• 2014

In Software Defined Network (SDN), data plane and control plane are decoupled. Dummy switches on the data plane simply forward packet based on the flow entries that are stored in its flow table. The flow entries are generated by a centralized controller that acts as a brain of the network. However, the size of flow table is limited and it can conduct a security issue related to Distributed Denial of Service (DDoS). Especially, it related to resource attack that consumes all flow table resource and consumes controller resources. In this paper, we will analyze the impact of flow table limitation to the controller. Then we propose an approach that is called Flow Table Management to handle flow table limitation.

• The Korean Journal of Health Service Management
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• v.8 no.1
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• pp.87-102
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• 2014

This study is a descriptive research one and its purpose is to understand subjective xerostomia, JFL and quality of life of the elderly and to apprehend its variable correlation and variables which influence on the OHRQOL. Subjects in this study were over 65-year-old the elderly in city B and the data of 116 ones were collected using the questionnaires from May 6, 2013 to June 7 from them. Collected data were analyzed as descriptive statistics, t-test, one-way ANOVA, Sheffe, Pearson's correlation coefficient and Multiple Regression using program SPSS 18.0. The most influenced factors of OHRQOL were JFL(${\beta}$=-.366), xerostomia(${\beta}$=-.248) and diseases of oral cavity (gingivitis)(${\beta}$=-.172) in order. These factors occupied 73% of OHRQOL. Therefore, development of nursing intervention to develop a program for the improvement in behavior and education to reduce xerostomia, JFL, gingivitis and to improve the OHRQOL elderly development of nursing interventions are required.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.296-304
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• 2015

Vessel Traffic Service (VTS) is the service that provides ships navigating on a sea transportation route with guidance and advice about geographical environment and other attentive information for their safety. In this study we point out that currently, constructing additional VTSs is required to prevent ships from unexpected accident on their navigation. We first select several candidate locations for constructing VTSs, based on the amount of marine transportation and its potential development possibility. Then, we present an optimization model in which the maximum area coverage is achieved by determining new locations of VTS subject to budget limitation. The problem can be modeled as a binary integer program and it provides an optimal solution for new VTS locations to be constructed under the consideration of the currently located VTSs in Korea.

• Archives of Obesity and Metabolism
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• v.1 no.2
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• pp.47-52
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• 2022

Digital therapeutics (DTx) are emerging as a novel solution to improve lifestyle and prevent non-communicable diseases. Obesity is a complex, multi-factorial, chronic condition that requires patient-centered lifestyle modification. DTx, such as mobile applications and wearables, may offer easily accessible, efficient, and personalized care in the field of obesity and metabolic diseases. Yet, there is controversy over its clinical usefulness. This review will provide a comprehensive overview of DTx, including its potential role and current limitation in obesity care, based on recent literature.

• Management Science and Financial Engineering
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• v.16 no.1
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• pp.81-117
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• 2010

Semi-supervised learning incorporates unlabeled examples, whose labels are unknown, as well as labeled examples into learning process. Although transductive support vector machine (TSVM), one of semi-supervised learning models, was proposed about a decade ago, its application to large-scaled data has still been limited due to its high computational complexity. Our previous research addressed this limitation by introducing a branch-and-bound algorithm for finding an optimal solution to TSVM. In this paper, we propose three new techniques to enhance the performance of the branch-and-bound algorithm. The first one tightens min-cut bound, one of two bounding strategies. Another technique exploits a graph-based approximation to a support vector machine problem to avoid the most time-consuming step. The last one tries to fix the labels of unlabeled examples whose labels can be obviously predicted based on labeled examples. Experimental results are presented which demonstrate that the proposed techniques can reduce drastically the number of subproblems and eventually computational time.

• Journal of the Korean Operations Research and Management Science Society
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• v.36 no.1
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• pp.39-55
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• 2011

Process monitoring has been emphasized for the monitoring of complex system such as chemical processing industries to achieve the efficiency enhancement, quality management, safety improvement. Recently, ICA (Independent Component Analysis) based MSPC (Multivariate Statistical Process Control) was widely used in process monitoring approaches. Moreover, DICA (Dynamic ICA) has been introduced to consider the system dynamics. However, the existing approaches show the limitation that their performances are strongly dependent on the statistical distributions of control variables. To improve the limitation, we propose a novel approach for process monitoring by integrating DICA and LOF (Local Outlier Factor). In this paper, we aim to improve the fault detection rate with the proposed method. LOF detects local outliers by using density of surrounding space so that its performance is regardless of data distribution. Therefore, the proposed method not only can consider the system dynamics but can also assure robust performance regardless of the statistical distributions of control variables. Comparison experiments were conducted on the widely used benchmark dataset, Tennessee Eastman process (TE process), and showed the improved performance than existing approaches.