• Journal of the Korea Society of Computer and Information
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• v.16 no.8
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• pp.29-38
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• 2011

Unlike in traditional row-oriented database systems, a column-oriented database system stores data in column-oriented and not row-oriented order. Recently, research results revealed the effectiveness of column-oriented databases for applications such as data warehouse and decision support systems that access large volumes of data in a read only manner. In this paper, we investigate the join strategies for column-oriented databases and prove the effectiveness of column-oriented databases in data warehouse systems. For unbiased comparison, the two database systems are analyzed using the star schema benchmark and the performance analysis of a star schema join query is carried out. We experimented with well-known join algorithms and considered early materialization and late materialization join strategies for column-oriented databases. The performance results confirm that star schema join queries perform better in terms of disk I/O cost in column-oriented databases than in row-oriented databases. In addition, the late materialization strategy showed more performance gain than the early materialization strategy in column-oriented databases.

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.137-147
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• 2018

The purpose of this study was to analysis total number of 123 SSI programs by SSI criteria. The criteria was consisted of subject, school level, starting point, scientific evidence, social content, use of scientific knowledge, level of conflict of interest, and evaluation and reflection. The results of the analysis are as follows. First, elementary school programs were the most and middle school programs were relatively few. Second, starting point was mainly in the actual situation, the fiction and nonfiction situation, and the situation including the controversy and conflict was less than 10%. Third, it was based on scientific evidence but mainly influenced by individual values and perceptions. Fourth, social contents were developed mainly in ethics/morality/value, political/social life/economy, environment contents. Fifth, the use of scientific knowledge mainly consisted of scientific decision making, scientific critical thinking, and information search. However, science inquiry, risk assessment, and cost effectiveness were less than 10%. Scientific inquiry is the essential factor of science education, and one of core competencies of national science curriculum. SSI program should be able to experience various kinds of conflicts, and to evaluate and reflect through reflection.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.2
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• pp.240-260
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• 2006

Purpose : The objective of this study is to serve guidelines for the investigation and management of uterine myomas with KM therapies. Methods : English-language articles from PubMed and Korean-language articles from the database of the journal of oriental gynecology were reviewed from 2000 to 2005, using the key words 'uterine myoma', 'uterine leiomyoma', 'fibroid', 'uterine artery embolization', 'endometrial ablation', 'myomectomy', and jagungguenjong(子宮筋腫)'. Results and Limits : The areas of clinical practices considered in formulating this guideline are assessment, KM therapies, medical treatments, myolysis, selective artery occlusion, endometrial ablation and surgical therapies including myomectomy and hysterectomy. Implementation of this guideline would optimize the decision-making process of women with uterine myomas and further investigation or therapy of their KM doctors. But we don't have abundant evidences of clinical trials of uterine myoma treated with KM therapy, though we treat or manage that with every-day clinical practices. Moreover cultural gaps between Korea and other western countries make many differences in the attitude to surgical therapies, especially hysterectomy. So it is very difficult to compare W therapies with other therapies. Moreover it is much difficult to estimate cost-effectiveness and benefit of those therapies in QOL. Conclusions : The majority of uterine myoma is asymptomatic and will not require any intervention or further investigation. But unmarried women who wish to marry and get pregnant want to find safe therapy for their asymptomatic uterine myomas. In that case, most of the patients prefer non-surgical therapy to surgical therapy. So KM herbal medicinal therapy is a good alternative method for those patients. For the symptomatic myomas, hysterectomy offers a definitive solution. However, it is not the best solution for women who wish to preserve their uterus. So KM therapy is a good alternative for them. But the predicted benefits of alternative therapies including KM therapy must be carefully weighed against the Possible risks of these therapies. To improve the quality of life of both women with asymptomatic and symptomatic myomas, selecting and treating patients should be done carefully. Moreover, the effect of KM therapy has to evaluated, comparing the possible situation without treatment and the benefit of constant treatment as a health-care system.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.37
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• pp.187-216
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• 2008

Risk regarding the possibility of loss can be especially problematic. If a loss is certain to occur, it may be planned for in advance and treated as a definite, known expense. It is when there is uncertainty about the occurrence of a loss that risk becomes an important problem. The word risk is often used in connection with insurance. No one generally accepted definition of risk exists, however. Of the many definitions, two distinctive ones are commonly used. One defines risk as the variation in possible outcomes of an event based on chance. That is, the greater the number of different outcomes that may occur, the greater the risk. Another way of expressing this concept is to state: The greater the variation around an average expected loss, the greater the risk. The second definition of risk is the uncertainty concerning a possible loss. The definition of risk as a useful one because it focuses attention on the degree of risk in given situations. The degree of risk is a measure of the accuracy with which the outcome of an event based on chance can be predicted. For now, it will serve our purpose to note the more accurate the prediction of the outcome of an event based on chance, the lower the degree of risk. After sources of risks are identified and measured, a decision can be made as to how the risk should be handled. A pure risk that is not identified does not disappear, the business merely loses the opportunity to consciously decide on the best technique for dealing with that risk. The process used to systematically manage risk exposures is known as risk management. Some persons use the term risk management only in connection with businesses, and often the term refers only to the management of pure risks. In this sense, the traditional risk management goal has been to minimize the cost of pure risk to the company. But as firms broaden the ways that they view and manage many different types of risk, the need for new terminology has become apparent. The terms integrated risk management and enterprise risk management reflect the intent to manage all forms of risk, regardless of type. International trade transaction is called between countries has features of globalism, cultural gap, long distance and long terms for the transaction. It is riskier than domestic transaction has its specific risks, such as foreign exchange risk and political risk, and requires various active risk management skills. Risks in relation to the international trade transaction are the contract risk, transit risk and payment risk, etc. The risk management in relation to the international trade transaction is to identify and measure these risks. The purpose of this study is to analyse the practical problems and its solution plan by analyzing various cases related to the risk management of bill of lading in the international trade transaction.

• Environmental and Resource Economics Review
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• v.26 no.3
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• pp.359-398
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• 2017

Uncertainty is central to energy and climate policy. A growing number of literature show that almost all components of energy and climate models are, to some extent, uncertain and that the effect of uncertainty on the model outputs, in turn policy recommendations, is significantly large. Most existing energy and climate-economy models developed and used in Korea, however, do not take uncertainty into account explicitly. Rather, many models conduct a deterministic analysis or do a simple (limited) sensitivity analysis. In order to help social planners to make more robust decisions (across various plausible situations) on energy and climate change issues, an uncertainty analysis should be conducted. As a first step, this paper reviews the theory of decision making under uncertainty and the method for addressing uncertainty of existing probabilistic energy and climate-economy models. In addition, the paper proposes a strategy to apply an uncertainty analysis to energy and climate-economy models used in Korea. Applying the uncertainty analysis techniques, this paper revises the FUND model and investigates the impacts of climate change in Korea.

• Environmental and Resource Economics Review
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• v.29 no.2
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• pp.219-246
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• 2020

From the Phase II (2018~2020) of K-ETS, the offset credit from 'CDM projects that domestic companies and others have carried out in foreign countries' can be used in the K-ETS. As a result, stakeholders in the K-ETS market are actively developing overseas CDM projects, such as the 'high-efficiency cook stove project'. which can secure a large amount of credits while marginal cost is relatively low. This paper develops the investment decision-making model of offset project for the 'high-efficiency cook stove project' using the real option approach. Under the uncertainty of the emission allowance price, the optimal investment threshold (p^⁎) is derived and sensitivity analysis is conducted. As a result, in the standard scenario (PoA-S), the optimal investment threshold is 29,054won/ton, which is lower than the stock price (p^⁎_spot). However, allocation entities are not only economics in the CDM project, but also CDM risk factors such as non-renewable biomass ratio, cook stove replacement ratio, equity ratio with host country, investment period and submission limitation of emission allowance. In addition, offset project developers will be able to derive the optimal investment threshold for each business stage and use it for economic feasibility checks.

• Quality Improvement in Health Care
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• v.9 no.2
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• pp.116-133
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• 2002

Background : It is very common in Korea to take care of non-acute patients in an acute setting, due to the lack of long-term facilities. Long term hospitalization increase medical expenses and decreases the bed utilization, which can affect the urgent and emergent admissions, and eventually jeopardize the hospital financially. In this study, strategies for effective transfers to the lower levels of care, and to decrease the length of stay were presented by surveying and analyzing the patient's knowledge of the transfer needs, and the willingness to transfer those whose hospital length of stay was more than 30days. Method : The survey is subject to a group of 251 patients who have been hospitalized over 30 days in a general hospital in Seoul. Excluding those that were in the Intensive Care Unit and psychiatric ward, 214 in-patients were used as participants. They were surveyed from April 9, 2002 to April 17, 2002. One hundred and thirty seven out of 214 were responded which made the response rate 64%. Data were analyzed by SAS and SPSS. Result : Multi-variable Logistic Regression Analysis showed a significant effect in medical expenses, knowledge of referral system and the information of the receiving hospital. The financial burden in medical expenses made the patient 10.7 times more willing to be transferred, knowledge of the referral system made them 5 times more willing to be transferred, and the information of receiving hospital makes 6.5 times more willing to be transferred. Reasons for willing to be transferred to a lower level of care were the phase of physical therapy, the distance from home, the attending physician's advice and being unable to be treated as an out patient. Reasons for refusing to be transferred were the following. The attending physician's competency, not being ready to be discharged, not trusting the receiving hospital's competency due to the lack of information, or never hearing about the referring system by the attending physician. Conclusion : Based on this, strategies for the effective transfer to the lower levels of care were suggested. It is desirable for the attending physician to be actively involved by making an effort to explain the transfer need, and referring to the Healthcare Coordinating Center, which can help the patient make the right decision. Nationwide networking for the referral system is the another key factor that may need to be suggested as an alternative to decrease the medical expenses. Collaborating with the Home Health Agency for the early discharge planning and the Social Service Department for financial aid are also needed. It is recommended that the hospital should expedite the transfer process by prioritizing the cost and the information as medical expenses, knowledge of referring system and the information of the receiving hospital, are the most important factors to the willingness to transfer to a lower level of care.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.164-170
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• 2017

The CNC machine tool field is showing a growing trend with the recent rapid development of manufacturing industries such as semiconductors, automobiles, medical devices, various inspection and test equipment, mechanical metal processing equipment, aircraft, shipbuilding and electronic equipment. However, small and medium-sized machining companies that use CNC machine tools are experiencing difficulties in increasingly intense competition. Especially, small companies which are receiving orders from 3rd or 4th venders are very difficult in business management. In recent years, company S experienced difficulty to make product quality and delivery time due to the ignorance of the processing method when manufacturing cooling plate jig made of SUS304 material used for cell phone liquid crystal glass processing. In order to solve these problems, we redesigned the process according to the size of our company and tried to manage all processes with quantified data. In the meantime, we have found that there is a need to improve the cutter process, which accounts for most of the machining process. Therefore, we have investigated the correlation between RPM and FEED of three cutters that have been used in the past. As a result, we found that it is the most urgent problem to solve the roughing process during the cutter operation which occupies more than 70% of the total machining. In order to shorten the machining time and improve the quality in machining of SUS304 cooling plate jig, we select the main factors such as price, tool life, maintenance cost, productivity, quality, RPM, and FEED and use AHP to find the most suitable milling cutter. We also tried to solve the problem of delivery, quality and production capacity which was a big problem of S company through experiment operation with selected cutter tool. As a result, the following conclusions were drawn. First, the most efficient of the three cutters currently available in the machining center has proven to be an M-cutter. Second, although one additional facility was required, it was possible to produce the existing facilities without additional investment by supplementing the lack of production capacity due to productivity improvement. Third, the Company's difficulties in delivery and capacity shortfalls have been resolved. Fourth, annual sales increased by KRW 109 million and profits increased by KRW 32 million annually. Fifth, it can confirm the usefulness of AHP method in corporate decision making and it can be utilized in various facility investment and process improvement in the future.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.729-738
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• 2017

With the signing of the Paris Agreement, which is the new climate change agreement at the end of 2015, it will have a great impact on Korea environmental policy. The construction industry, which accounts for 42% of Korea's total $CO_2$ emissions, has been implementing various policies to improve the environmental problems. However, it is only applying passively to other projects except eco-friendly building certification. This is because most of the eco-related systems are based on building facilities. Therefore, there is a need for a new eco - friendly design evaluation model that can be widely applied not only to architecture but also to civil engineering facilities. In this study, a new model is developed based on the existing VE model, which adds new factors to evaluate the environmental friendliness, potential environmental pollution concept and environmental risk of facilities. This model is an eco-friendly design evaluation model that enables decision makers to effectively select alternative environmental criteria at the design stage. As a result of the case analysis of the block retaining wall and the alternative retaining wall, the value of the eco - friendly value of the alternative was 1.026 times higher than the original one. If this model is used at the design stage, it is expected to contribute not only to the construction of environmentally friendly facilities but also to the reduction of carbon emissions.

• Korean Journal of Health Education and Promotion
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• v.26 no.2
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• pp.75-86
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• 2009

Objectives: To identify the factors associated with the intention to undergo mammography among Korean women without a prior screening experience. Methods: Among 1,039 women of the general population, we selected 145 women (mean age: 54.2 years, age range : 40-78 years) without any prior experience with mammography. They were recruited for the 'Cancer Information Needs Assessment Survey' by using the method of random multi-stage cluster sampling. Data on the socio-demographic characteristics, intention to undergo mammography based on the Precaution Adoption Process Model, level of self belief and self efficacy for breast cancer screening, motivation for decision to undergo breast cancer screening were obtained by conducting a household survey. Results: Of the study subjects, 49.7% were classified as "unengaged" and "decided not to act" regarding breast cancer screening. Women with the intention to undergo mammography were more likely to be younger (OR 0.11, 95%CI 0.04-0.36), to have been recommended to undergo screening by others (OR 3.27, 95%CI 1.36-7.87), to have a high level of perceived sensitivity (OR 3.15, 95%CI 1.27-7.82), and to have a high level of self efficacy (OR 1.09, 95%CI 0.97-1.23). Exposure to campaigns and information regarding breast cancer screening, whether cancer patients are or not in around, perceived severity, perceived benefit, and perceived cost were factors that were not significantly associated with the intention to undergo mammography. Conclusion: It is necessary to develop tailored intervention strategies for women who have never undergone breast cancer screening on the basis of their demographic characteristics and factors that positively influence the intention to undergo mammography.