• International conference on construction engineering and project management
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• 2011.02a
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• pp.534-541
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• 2011

Risk evaluation approaches for bidding on international construction projects are typically partitioned into three stages: country selection, project classification, and bid-cost evaluation. However, previous studies are frequently under attack in that they have several crucial limitations: 1) a dearth of studies about country selection risk tailored for the overseas construction market at a corporate level; 2) no consideration of uncertainties for input variable per se; 3) less probabilistic approaches in estimating a range of cost variance; and 4) less inclusion of covariance impacts. This study thus suggests a three-staged risk evaluation model to resolve these inherent problems. In the first stage, a country portfolio model that maximizes the expected construction market growth rate and profit rate while decreasing market uncertainty is formulated using multi-objective genetic analysis. Following this, probabilistic approaches for screening bad projects are suggested through applying various data mining methods such as discriminant logistic regression, neural network, C5.0, and support vector machine. For the last stage, the cost overrun prediction model is simulated for determining a reasonable bid cost, while considering non-parametric distribution, effects of systematic risks, and the firm's specific capability accrued in a given country. Through the three consecutive models, this study verifies that international construction risk can be allocated, reduced, and projected to some degree, thereby contributing to sustaining stable profits and revenues in both the short-term and the long-term perspective.

• Journal of Family Resource Management and Policy Review
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• v.25 no.4
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• pp.71-86
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• 2021

The purpose of this study is to identify the influencing factors of married men's household labor time by generation to understand the changes in male participation in household labor. To this end, married men were classified into Baby Boomers, Generation X, and Generation Y, and the factors of participation in household labor for each generation were analyzed by applying the hypothesis of participation in household labor. As for the data, the original data of the National Statistical Office's "2019 Time Use Survey" were used. Multinomial logistic analysis was conducted to analyze the factors affecting married men's household labor time. As a result of the analysis, household labor time for Baby Boomers can be explained by the hypothesis of economic efficiency, gender role attitude, and the demand/response capability, while household labor time for Generation X can be explained by economic efficiency hypothesis, gender role attitude hypothesis, time-availability hypothesis, and demand/response capability hypothesis. It was found that the household labor time for Generation Y can be explained by the time-availability hypothesis and demand/response capability hypothesis. The fact that each generation has different factors of participation in household labor suggests that the characteristics of each generation should be considered in establishing policies to support the work and family balance for men.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.4
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• pp.143-148
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• 2015

Objective: The aim of the current study was to determine the predictive value of anti-$M{\ddot{u}}llerian$ hormone (AMH) levels for pregnancy outcomes in patients over 40 years of age who underwent in vitro fertilization or intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles. Methods: We retrospectively analyzed the medical records of 188 women aged 40 to 44 years who underwent IVF/ICSI-fresh ET cycles due to unexplained infertility in the fertility center of CHA Gangnam Medical Center. Patients were divided into group A, with AMH levels <1.0 ng/mL (n=97), and group B, with AMH levels ${\geq}1.0ng/mL$ (n=91). We compared the clinical pregnancy rate (CPR) in the two groups and performed logistic regression analysis to identify factors that had a significant effect on the CPR. Results: The CPR was significantly lower in group A than group B (7.2% vs. 24.2%, p<0.001). In multivariate logistic regression analysis, AMH levels were the only factor that had a significant impact on the CPR (odds ratio, 1.510; 95% confidence interval, 1.172-1.947). The area under the receiver operating characteristic curve for AMH levels as a predictor of the CPR was 0.721. When the cut-off level of AMH was set at 1.90 ng/ mL, the CPR was 6.731-fold higher in the group with AMH levels ${\geq}1.90ng/mL$ than in the group with AMH levels <1.90 ng/mL (p<0.001). Conclusion: Our study showed that AMH levels were predictive of clinical pregnancy in infertility patients over 40 years of age. Further prospective studies should be conducted to validate the predictive capability of AMH levels for the outcome of clinical pregnancy.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.6
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• pp.139-150
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• 2017

In Korea, small and medium-sized enterprises (SMEs) play an pivotal role in the national economy, accounting for 99.9% of all enterprises, 87.9% of total employment, and 48.3% of production. In spite of their crucial role in the national development, most of SMEs suffer from a lack of R&D related resources. Public R&D organizations such as government-funded research institutes can provide SMEs with valuable supplementary technological knowledge and help them build technological capacity. In this regard, this study estimated the effect of internal R&D investment and private-public R&D cooperation on technological innovation of ICT SMEs based on 2016 ETRI Survey. Building on previous literatures, the study established and tested a research model using binary logistic regression analysis. First, internal R&D investment and preferences for open innovation demonstrated the strengthening of R&D collaboration. Second, internal R&D investment and R&D cooperation showed a positive effect on both product and process innovation. Therefore, internal R&D capability and taking advantage of R&D collaboration are needed to achieve technological innovation for SMEs in ICT sector. This study also discuss implications for encouraging private-public R&D cooperation.

• Science of Emotion and Sensibility
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• v.16 no.3
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• pp.409-416
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• 2013

Attention is one of important cognitive functions in human affecting on the selectional concentration of relevant events and ignorance of irrelevant events. The discrimination of attentional and inattentional status is the first step to manage human's attentional capability using computer assisted device. In this paper, we newly combine the non-linear recurrence pattern analysis and spectrum analysis to effectively extract features(total number of 13) from the electroencephalographic signal used in the input to classifiers. The performance of diverse types of attention-inattention classifiers, including supporting vector machine, back-propagation algorithm, linear discrimination, gradient decent, and logistic regression classifiers were evaluated. Among them, the support vector machine classifier shows the best performance with the classification accuracy of 81 %. The use of spectral band feature set alone(accuracy of 76 %) shows better performance than that of non-linear recurrence pattern feature set alone(accuracy of 67 %). The support vector machine classifier with hybrid combination of non-linear and spectral analysis can be used in later designing attention-related devices.

• The Korean Journal of Community Living Science
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• v.18 no.1
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• pp.147-160
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• 2007

This research challenges the general notion of one-person households of the elderly during widowhood as impoverished, isolated, and vulnerable. Recognizing a high potential vulnerability, however, this research attempts to describe the diverse composition of one-person households of the elderly. For this purpose, relying on 2% sample data from the 2000 census, it examines regional distribution, socio-economic characteristics, and determinants of one-person households of the elderly during widowhood. Socio-economic characteristics of one-person households of the elderly differ by region. Jeju island is distinct in terms of sex and age distribution, and residence area of children. In general, rates of economic activity and self-subsistence are higher in provinces than in cities. Compared to the elderly living with family, the elderly living alone show high rates of economic activity, self-subsistence, and capability of physical activity. Results of logistic regression analysis of determinants of living arrangement are consistent with those of descriptive statistics. Those who are economically active and able to move around without assistance tend to live alone after the death of a spouse. Number of sons and living in an urban area are negatively associated with living alone, whereas females are more likely than males to live alone. According to the separate analysis by age, the positive effect of economic activity is greater in the oldest of the old than in other age groups. Those who possess high educational attainment tend to live alone when they are 80 and older, unlike other age groups. Based on these findings, this paper finds that one-person households of the elderly nay not always be the most vulnerable group, and are diverse in terms of socioeconomic characteristics.

• Journal of Navigation and Port Research
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• v.35 no.3
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• pp.271-279
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• 2011

This study aims at searching the global strategy which can raise the competitive power of IEC(International Express Companies) in Korea analyzing and coping with the international express companies and global factor of promotion. The global strategy varialbe for IEC- invigorating in korea is composed with nine variables which is M&A strategy, Intergrated logistics enterprise strategy, Globalized alliance strategy, SCM stratege, the third party operating strategy, Total logistic operating system strategy, Differentiated service providing strategy, Phased market entry strategy, Core capability strengthen strategy. According to the result of study, the global strategy influence for the nature of international express company's and increasing competitiveness is depend on specialization strategy and using scale of economy for globalization strategy.

• Quality Improvement in Health Care
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• v.10 no.2
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• pp.216-231
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• 2003

Objectives: To develop a model that predicts a death probability of acute myocardial infarction(AMI) patient, and to evaluate a performance of hospital services using the developed model. Methods: Medical records of 861 AMI patients in 7 general hospitals during 1996 and 1997 were reviewed by two trained nurses. Variables studied were risk factors which were measured in terms of severity measures. A risk model was developed by using the logistic regression, and its performance was evaluated using cross-validation and bootstrap techniques. The statistical prediction capability of the model was assessed by using c-statistic, $R^2$ as well as Hosmer-Lemeshow statistic. The model performance was also evaluated using severity-adjusted mortalities of hospitals. Results: Variables included in the model building are age, sex, ejection fraction, systolic BP, congestive heart failure at admission, cardiac arrest, EKG ischemia, arrhythmia, left anterior descending artery occlusion, verbal response within 48 hours after admission, acute neurological change within 48 hours after admission, and 3 interaction terms. The c statistics and $R^2$ were 0.887 and 0.2676. The Hosmer-Lemeshow statistic was 6.3355 (p-value=0.6067). Among 7 hospitals evaluated by the model, two hospitals showed significantly higher mortality rates, while other two hospitals had significantly lower mortality rates, than the average mortality rate of all hospitals. The remaining hospitals did not show any significant difference. Conclusion: The comparison of the qualities of hospital service using risk-adjusted mortality rates indicated significant difference among them. We therefore conclude that risk-adjusted mortality rate of AMI patients can be used as an indicator for evaluating hospital performance in Korea.

• Journal of Preventive Medicine and Public Health
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• v.24 no.3 s.35
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• pp.265-278
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• 1991

This study was to examine the effects of insurance coverage on the utilization of public health institutions and to identify the factors associated with the utilization. The data were obtained from household interview surveys conducted twice in Hwachun Gun, Kangwon Do. The time period covered in the first survey was December $17{\sim}31$, 1987, before the implementation of regional medical insurance for the self-employed, and that of the second survey was January 28 $\sim$ Febuary 11, 1990, after its implementation. Major findings emerged from the analysis can be summarized as follows (1) Medical care utilization of rural people markedly increased after they were covered by medical insurance. The insurance coverage increased the utilization of public health institutions as well, and this increase was mainly attributable to the utilization by chronically ill patients. (2) Between 1987 and 1990, the proportion of the utilization of public health institutions over whole medical care utilization decreased. But the proportion increased for chronically ill patients covered by regional medical insurance during the same time span. (3) The results of logistic regression suggested that the rural self-employed utilized public health institutions at an increased rate after they were covered by medical insurance. It was also indicated that the increase resulted from the utilization by chronically ill patients. (4) The relative importance of public health institutions for rural medical care decreased after the implementation of regional medical insurance. But considering that the utilization of public health institutions by chronically ill patients increased after insurance coverage, attention should be directed to improving the capability of public health institutions to control chronic degenerative diseases.

• Journal of Preventive Medicine and Public Health
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• v.42 no.5
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• pp.275-282
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• 2009

Objectives : This study aimed to verify the association between wealth or income level and health status after adjusting for other socio-economic position (SEP) indicators among Korean adults aged 45 and over. Methods : Data were obtained from the 1st wave of Korean Longitudinal Study of Ageing (households: 6,171, persons: 10,254). We used self-rated health status and activities of daily living (ADLs) as dependent variables. Explanatory variables included both net wealth measured by savings, immovables, the other valuated assets and total income including pay, transfer, property and so on. Binary logistic regression was conducted to examine the relationships. Also, in order to determine the relative health inequality across economic groups, we estimated the relative index of inequality (RII). Results : The inequality of health status was evident among various wealth and income groups. The wealthiest group (5th quintile) was much healthier than the poorest group, and this differential increased with age. Likewise, higher income was associated with better health status among the elderly. However, these effects, as measured by the odds ratio and RII, showed that wealth was more important in determining health status of elderly people. Conclusions : This study suggests that economic capability plays a significant role in determining the health status and other health-related problems among the elderly. Particularly, our results show that health status of the aged is related more closely to the individual s wealth than income.