• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.525-535
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• 2018

If the frequency of a particular class is excessively higher than the frequency of other classes in the classification problem, data imbalance problems occur, which make machine learning distorted. Corporate bankruptcy prediction often suffers from data imbalance problems since the ratio of insolvent companies is generally very low, whereas the ratio of solvent companies is very high. To mitigate these problems, it is required to apply a proper sampling technique. Until now, oversampling techniques which adjust the class distribution of a data set by sampling minor class with replacement have popularly been used. However, they are a risk of overfitting. Under this background, this study proposes ROSE(Random Over Sampling Examples) technique which is proposed by Menardi and Torelli in 2014 for the effective corporate bankruptcy prediction. The ROSE technique creates new learning samples by synthesizing the samples for learning, so it leads to better prediction accuracy of the classifiers while avoiding the risk of overfitting. Specifically, our study proposes to combine the ROSE method with SVM(support vector machine), which is known as the best binary classifier. We applied the proposed method to a real-world bankruptcy prediction case of a Korean major bank, and compared its performance with other sampling techniques. Experimental results showed that ROSE contributed to the improvement of the prediction accuracy of SVM in bankruptcy prediction compared to other techniques, with statistical significance. These results shed a light on the fact that ROSE can be a good alternative for resolving data imbalance problems of the prediction problems in social science area other than bankruptcy prediction.

• Korean Journal of Construction Engineering and Management
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• v.12 no.2
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• pp.3-11
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• 2011

There are several causes to recalculate the contract amount in public construction projects. Among them, the escalation clause was introduced in 1969 and now the condition to recalculate the cost is effective after 90 days from the date of contract and the rate of fluctuation should be more than 3% from the date of bidding. The two calculation methods for the rate of fluctuation are item-adjustment and index-adjustment. According to the results of investigation into 4 public institutions and 163 projects, all of them have used the method of index-adjustment and the rate of projects that spend over 6 months obtaining the approval of contract amount adjustment is more than 90%. The reason for spending lots of time is caused by problems of the calculation method on the price fluctuation rate. Therefore, it is necessary that the calculation method should be diversified to cope with the problems and a option of the builder should be expanded as well. Furthermore, if the way to apply correction factors to construction price index and average index based on the producer and consumer price index made by the bank of Korea is added, then the duration will be reduced without additional expenses. This study proposed the diversification of the calculation method using price fluctuation rate and builders' expanded options as improvement on the managerial method of Price Fluctuation System for the prompt and efficient contract amount adjustment.

• The KIPS Transactions:PartA
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• v.19A no.1
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• pp.51-60
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• 2012

IC(Integrated circuits)card, generally be named smard card, embedded MPU(Micro Processor Unit) of small-size, memory, EEPROM, Card Operating System(COS) and security algorithm. The IC card is used in almost all industry such as a finance(credit, bank, stock etc.), a traffic, a communication, a medical, a electronic passport, a membership management and etc. Recently, a application field of IC card is on the increase by method for payments of T-commerce, as T-commerce is becoming a new growth engine of the broadcating industry by trend of broadcasting and telecommunication convergence, smart mechanization of TV. For example, we can pay in IC credit card(or IC cash card) on T-Commerce. or we can be provided TV banking service in IC cash card such as ATM. However, so far, T-commerce payment services have weakness in security such as storage and disclosure of card information as well as dropping sharply about custom ease because of taking advantage of card information input method using remote control. To solve this problem, This paper developed processing payment module for implementing TV electronic payment system using IC credit card payment standard, EMV.

• The Korean Journal of Blood Transfusion
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• v.23 no.2
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• pp.136-144
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• 2012

Background: Fresh frozen plasma (FFP) transfusion is administered primarily for management of acquired bleeding disorders. However, in practice, FFP transfusion is increasing without a solid rationale. Methods: We conducted an audit to evaluate the appropriateness of the indications for FFP transfusion during the period from July 2010 through June 2011. Assessment of the appropriateness of the indications was based on the national transfusion guidelines and the transfusion criteria promulgated by the Severance Hospital. Results: In total, 17,733 units of plasma were transfused to 1,949 patients over 4,982 events. We found that administration of FFP was not in compliance with the recommended guidelines in 1,990 events. The number of total FFP transfusions was higher in medical departments (Gastroenterology) than in surgical departments (Thoracic and cardiovascular surgery, General surgery). However, the proportion of cases of inappropriate transfusion was higher in surgical departments than in medical departments. Both the total number of FFP transfusion and the proportion of inappropriate transfusion were high in patient with neoplasm, disease of the digestive system, and diseases of the circulatory system. Conclusion: Continuous monitoring on appropriateness for FFP transfusion and feedback to the physician are critical in securing the transfusion safety as well as maintaining the quality of FFP transfusion. New-found indication for FFP transfusion should be investigated and applied in timely manner.

• International Area Studies Review
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• v.15 no.2
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• pp.125-150
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• 2011

As the economy grows, there is a concern that the economic development causes a productivity reduction because of the service intensive growth. However, the economy of developed countries encounter with the productivity growth as their economy grows, which phenomenon called Baumol's paradox. Oulton (1999, 2001) find out the reason of Baumol's paradox in a forward and backward chain effects. So, this paper is aimed at verifying the theory of Oulton (1999, 2001). Moreover, we test the difference effect between a consumer service and producer service input using a dummy variable. We use the Input-Output Table (1990, 1995, 2000, 2005) that is offered by the Bank of Korea to accomplish the purpose of our research that is represented above. We find out that the Korea's intermediate producer service inputs cause a multifactor productivity growth. That result is matched with the Oulton (1999, 2001)'s theory. But, the intermediate consumer service inputs don't have a significant effect on a multifactor productivity. The result of verifying the effect of intermediate producer service inputs among industries shows that the effects on manufacture industries are less than other industries.

• Korean Journal of Clinical Laboratory Science
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• v.55 no.3
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• pp.203-212
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• 2023

Since the coronavirus disease-2019 (COVID-19) outbreak, it has been generally believed that a medical technologists (MTs) are supposed to perform polymerase chain reaction tests and next-generation sequencing (NGS) in the hospitals. However, many do not recognize that the duty of MT for clinical genetic testing has not been stated in the Medical Laws (72.5% for MT, N=200; 62.8% for students, N=123). In this regard, to evaluate the feasibility of MT's role for NGS genetic testing, we requested our subjects to fill out an online survey and analyzed the data. Among them, it shows that the scope of MT's role, including NGS performance should include clinical genetic testing (99.5% for MT, N=200; 86.8% for students, N=123). Also, questions on clinical genetics, which is associated with both cellular genetics and molecular genetic questions should be included in the National MT License Problem Bank (97.5% for MT; 71.4% for students). Based on these results, the Korean Association of Medical Technologists needs to cooperate synergically with the Academic Association of Biomedical Laboratory Science with respect to genetic education and legislation for the future benefit of both MTs and students.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5D
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• pp.783-796
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• 2006

Rut-resistance pavement is adopted to prevent pavement from plastic deformation since 1998. The objective of this paper is to investigate performance and economic efficiency between rut-resistance pavement and conventional hot-mix asphalt(HMA) on national highway. The pavement deterioration models incorporated in HDM-4 have been calibrated and adapted to local road conditions based on observed pavement rut-depth data. Based on calibration result of HDM-4, the economic evaluation including road agency cost and user cost is performed for 34 road pavement sections. Furthermore, we presented optimal timing for maintenance and performance levels subject to different budget. We found that rut-resistance pavement is performing better than conventional hot-mix asphalt in most road sections. Furthermore, we confirmed that the application of HDM-4 is useful for pavement project planning and evaluation. More investigation is needed to enlarge the scope of the pavement data and to explore more deeply socio-environmental cost and delay cost.

• Economic Analysis
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• v.25 no.1
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• pp.1-33
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• 2019

This paper examines the economic factors that are related to the dynamics of the variance risk premium, and specially, which economic factors are related to the forecasting power of the variance premium regarding future index returns. Eleven general economic variables, eight interest rate variables, and eleven sentiment-associated variables are used to figure out the relevant economic variables that affect the variance risk premium. According to our empirical results, the won-dollar exchange rates, foreign reserves, the historical/implied volatility, and interest rate variables all have significant coefficients. The highest adjusted R-squared is more than 65 percent, indicating their significant explanatory power of the variance risk premium. Next, to verify the economic variables associated with the predictability of the variance risk premium, we conduct forecasting regressions to predict future stock returns and volatilities for one to six months. Our empirical analysis shows that only the won-dollar exchange rate, among the many variables associated with the dynamics of the variance risk premium, has a significant forecasting ability regarding future index returns. These results are consistent with results found in previous studies, including Londono (2012) and Bollerslev et al. (2014), which show that the variance risk premium is related to global risk factors.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.13-27
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• 2024

The purpose of this study is to analyze whether startup CEOs' self-efficacy and hope have a mediating effect on the relationship between satisfaction with an acceleration program and business performance. While the impact of acceleration programs on business performance has been validated through various studies, this research aims to examine whether differences in business performance, despite participating in the same program, are attributable to the characteristics of the participants. To this end, satisfaction with the acceleration program was set as the independent variable, business performance (financial performance and non-financial performance) as the dependent variable, and self-efficacy and hope among positive psychological capital as the mediating variables. A survey was conducted on startup CEOs who participated in acceleration programs offered by financial public institutions, specifically the Korea Credit Guarantee Fund and the Industrial Bank of Korea, in order to minimize the influence of differences in accelerator competence and program quality. The empirical analysis results indicate that satisfaction with the acceleration program has a positive effect on both the financial and non-financial performance of startups, and hope serves as a mediating factor in this relationship. This study suggests that to improve business performance of startups, policy efforts are needed to activate and enhance the roles of domestic accelerators. Additionally, it proposes that in order to maximize the effectiveness of acceleration programs, detailed components of these programs should be designed to elevate the participants' level of hope.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.466-472
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• 2012

In this study, ribulose bisphosphate carboxylase (rbcL), RNApolymeraseC (rpoC1), intergenic spacer (psbA-trnH), and second internal transcribed spacer (ITS2) as identification markers for discrimination of P. mirifica in foods were selected. To be primer design, we obtained 719 bp, 520 bp, 348 bp, and 507 bp amplicon using universal primers from selected regions of P. mirifica. The regions of rbcL, rpoC1, and psbA-trnH were not proper for design primers because of high homology about P. mirifica, P. lobata, and B. superba. But, we had designed 4 pairs of oligonucleotide primers from ITS2 gene. Predicted amplicon from P. mirifica were obtained 137 bp and 216 bp using finally designed primers SFI12-miri-6F/SFI12-miri-7R and SFI12-miri-6F/SFI12-miri-8R, respectively. The species-specific primers distinguished P. mirifica from related species were able to apply food materials and processed foods. The developed PCR method would be applicable to food safety management for illegally distributed products in markets and internet shopping malls.