• Journal of Environmental Health Sciences
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• v.37 no.5
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• pp.387-395
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• 2011

Purpose: This study measured the burden of disease in Korea related to outdoor air pollution using disability-adjusted life year (DALY). Materials and Methods: As a risk factor of outdoor air pollution, particulate matter with a diameter less than 10 ${\mu}m$($PM_{10}$) was used. First, $PM_{10}$-related diseases and their relative risk (RR) were selected by means of a literature review. Second, population attributable fractions were computed by using formulae including RR and population exposure to $PM_{10}$. Third, DALYs of $PM_{10}$-related diseases in Korea were estimated. Finally, the attributable burden of disease due to $PM_{10}$ was measured as the sum of the products that multiplied the DALYs of $PM_{10}$-related diseases by their population attributable fractions. Results: The disease burden of PM10 was 6.9 DALY per 1,000 persons in 2007. The attributable burden of $PM_{10}$ was 2.68 for lung cancer, 2.41 for COPD, 0.62 for ischemic heart disease, 0.61 for pneumonia, 0.55 for asthma, and 0.03 for preterm. Conclusions: This study showed the environmental burden of disease of $PM_{10}$ and burden of $PM_{10}$-related disease through objective data. It also suggested that active efforts are needed to continuously measure and reduce the burden of environmental diseases in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5407-5409
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• 2014

Background: In National Cancer Registry Programme (NCRP) reports, various rates are routinely provided for 50 cancer sites of males and 54 cancer sites of females. Very often, depending on our interest, we wish to see these rates for group of cancers like head and neck cancers, oral cancers, and reproductive cancers. In such a situation, the desired rates are calculated independently from the actual data and reported. The question is can we derive the rates for groups of cancers from the published reports when the data is provided only for the individual sites? Objective: In the present paper, an attempt is made to explore the mathematical properties of various rates to derive them directly for the group of cancer sites from the published data when the rates are provided only for the individual sites. Source of data: The cancer incidence data collected by two urban Population Based Cancer Registries (PBCRs), under the network of NCRP for the period of 2006-08 was considered for the study purposes. The Registries included were: Bangalore and Bhopal. Results: In the present communication, we have shown that the crude rate (CR), age specific rates and age-adjuste rates (AAR) all possess additive properties. This means, given the above rates for individual sites, the above rates can be calculated for groups of sites by simply adding them. In terms of formula it can be stated that CR(Site1+Site2+++ SiteN) = CR(Site1)+CR(Site2) +++ CR(SiteN). This formula holds good for age specific rates as well as for AAR. This property facilitates the calculation of various rates for defined groups of cancers by simply adding the above rates for individual sites from which they are made up.

• Fire Science and Engineering
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• v.28 no.2
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• pp.69-75
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• 2014

This study derives the factors which affect the occurrence of arson from statistical data (population, economic, and social factors) by multiple regression analysis. Multiple regression analysis applies to 4 forms of functions, linear functions, semi-log functions, inverse log functions, and dual log functions. Also analysis respectively functions by using the stepwise progress which considered selection and deletion of the independent variable factors by each steps. In order to solve a problem of multiple regression analysis, autocorrelation and multicollinearity, Variance Inflation Factor (VIF) and the Durbin-Watson coefficient were considered. Through the analysis, the optimal model was determined by adjusted Rsquared which means statistical significance used determination, Adjusted R-squared of linear function is scored 0.935 (93.5%), the highest of the 4 forms of function, and so linear function is the optimal model in this study. Then interpretation to the optimal model is conducted. As a result of the analysis, the factors affecting the arson were resulted in lines, the incidence of crime (0.829), the general divorce rate (0.151), the financial autonomy rate (0.149), and the consumer price index (0.099).

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.4
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• pp.55-63
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• 2013

This study investigates the trends and uncertainty of the impacts of climate change on paddy rice production in the Geumho river basin. The Long Ashton Research Station stochastic Weather Generator (LARS-WG) was used to derive future climate data for the Geumho river basin from 15 General Circulation models (GCMs) for 3 Special Report on Emissions Scenarios (SRES) (A2, A1B and B1) included in the Intergovernmental Panel on Climate Change (IPCC) 4th assessment report. The Food and Agricultural Organization (FAO) AquaCrop, a water-driven crop model, was statistically calibrated for the 1982 to 2010 climate. The index of agreement (IoA), prediction efficiency ($R^2$), percent bias (PBIAS), root mean square error (RMSE) and a visual technique were used to evaluate the adjusted AquaCrop simulated yield values. The adjusted simulated yields showed RMSE, NSE, IoA and PBIAS of 0.40, 0.26, 0.76 and 0.59 respectively. The 5, 9 and 15 year central moving averages showed $R^2$ of 0.78, 0.90 and 0.96 respectively after adjustment. AquaCrop was run for the 2020s (2011-2030), 2050s (2046-2065) and 2090s (2080-2099). Climate change projections for Geumho river basin generally indicate a hotter and wetter future climate with maximum increase in the annual temperature of $4.5^{\circ}C$ in the 2090s A1B, as well as maximum increase in the rainfall of 45 % in the 2090s A2. The means (and ranges) of paddy rice yields are projected to increase by 21 % (17-25 %), 34 % (27-42 %) and 43 % (31-54 %) for the 2020s, 2050s and 2090s, respectively. The A1B shows the largest rice yield uncertainty in all time slices with standard deviation of 0.148, 0.189 and $0.173t{\cdot}ha^{-1}$ for the 2020s, 2050s and 2090s, respectively.

• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.469-476
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• 2000

Objectives : To analyze differences in health behaviors among the social strata in Korea by using the 1995 National Health and Health Behavior Survey Data. Methods : Study Participants numbered 2,352 men and 1,016 women aged between 15-64 years old, with housewives, students and non-waged family workers excluded. Health behaviors in this study were defined according to the recommendations of the Alameda 7 study. The measure of health behaviors was based on the Health Practices Index(HPI; 0-5 range, with the exclusion of snacking between meals and regularly eating breakfast) developed by the Alameda County research. The significance of the relationship between social strata and HPI was assessed by considering the adjusted means from the multi-variate model. Results : For men, incidence rates of never having smoked, no/moderate use of alcohol, regular exercise, and regular 7-8 hours sleep per night were higher in the upper social strate. Meanwhile, for women, incidence rates of never having smoked, no/moderate use of alcohol, appropriate weight, regular exercise, and regular 7-8 hours sleep per night were higher in the upper strata. HPI varied significantly among social strata in both sexes (p<0.001), a result which held true when adjusted for age, education, income, social insurance type, marital status and region. Conclusions : Health behaviors assessed by Health Practices Index(HPI) varied significantly among social strata for both sexes. Therefore, the existing gap in health behaviors among social strata can be corrected more effectively by target oriented health promotional activities.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.477-487
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• 2018

The purpose of this study was to examine the effects of burnout, verbal abuse experience, and social support on job embeddedness in the Small and Medium Sized Hospital Nurses. The data were collected from 497 nurses by means of self-reported questionnaires on August 23th to October 30th, 2017. The data were analyzed by t-test, ANOVA, Pearson's correlation coefficients and hierarchical multiple regression analysis. The results showed that burnout, verbal abuse experience, social support, and position were identified as the factors affecting the nurse's job embeddedness (Adjusted $R^2=.45$). Therefore, to enhance nurses' job embeddedness, it is necessary to reduce nurse's burnout and increase social supports from supervisor and colleague. Additionally, the nurse leaders should prepare a verbal abuse prevention program for nurses.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.87-94
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• 2005

Results from previous studies revealed that metal level in the body is related to certain types of diseases. For example. serum copper level with chronic heart failure, iron and transferrin in the blood serum with acute cerebral vascular diseases, Zn in the CNS, lead with neurotoxicity, hypertension, genetic damage, arsenic with cancer skin lesion, Al with neurobehavioral function (cognitive impairment and memory disorder), and etc. The rate of stroke has increased in recent years and several metals were found to be responsible for causing stroke. This study compared several blood metal concentrations between stroke and non-stroke patients. Patients with stroke (116 samples) and non-stroke (111 samples including lowback pain and others) participated in this study. Total of 227 blood samples were collected and participants completed questionnaires regarding age, gender, occupation, residence, alcohol, smoking, and etc. To be qualified into the stroke group, patients have never experienced stroke previously. Subjects only included ischemic stroke and intracerebral hemorrhage patients diagnosed by brain CT and brain MRI. Patients with high risk of metal exposure such as herbal intake and job related exposure were excluded. 10ml of blood samples were analyzed by ICP-MS method at the Center of Nature and Science at Sangji University. Metal geometric mean (SD) concentrations in blood of study subjects showed higher values, 2.64-36.12%, than WHO reference values in Mn, Ni, Hg, Se, and As. Metal concentration in blood of stroke patients non-adjusted for potential confounders was higher except for Hg and also higher except for Ni in adjusted for potential confounders. Co was significantly higher in stroke patients (p=0.002) than non-stroke patients adjusted for potential confounders. Regression coefficient values of stroke patients was 0.17-8.25 in each metals. Odd ratio of stroke patients had 0.96 (Ni)-2.68 (Co) compared to non-stroke cases. This result means that Co increase of 1 raises the risk ratio of stroke by 2.86 times. Based on the results, metal concentration in blood seems to affect incidence of stroke.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.2
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• pp.312-320
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• 2012

In this study, we introduce a new design methodology of a granular-oriented self-organizing polynomial neural networks (GoSOPNNs) that is based on multi-layer perceptron with Context-based Polynomial Neurons (CPNs) or Polynomial Neurons (PNs). In contrast to the typical architectures encountered in polynomial neural networks (PNN), our main objective is to develop a methodological design strategy of GoSOPNNs as follows : (a) The 1st layer of the proposed network consists of Context-based Polynomial Neuron (CPN). In here, CPN is fully reflective of the structure encountered in numeric data which are granulated with the aid of Context-based Fuzzy C-Means (C-FCM) clustering method. The context-based clustering supporting the design of information granules is completed in the space of the input data while the build of the clusters is guided by a collection of some predefined fuzzy sets (so-called contexts) defined in the output space. (b) The proposed design procedure being applied at each layer of GoSOPNN leads to the selection of preferred nodes of the network (CPNs or PNs) whose local characteristics (such as the number of contexts, the number of clusters, a collection of the specific subset of input variables, and the order of the polynomial) can be easily adjusted. These options contribute to the flexibility as well as simplicity and compactness of the resulting architecture of the network. For the evaluation of performance of the proposed GoSOPNN network, we describe a detailed characteristic of the proposed model using a well-known learning machine data(Automobile Miles Per Gallon Data, Boston Housing Data, Medical Image System Data).

• Journal of Educational Research in Mathematics
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• v.10 no.2
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• pp.161-182
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• 2000

This study is to develop assessment framework, test items and questionnaire for the National Assessment of Educational Achievement(NAEA), which administered in the elementary and secondary schools across the country in this year(2000). According to the first year study result of the NAEA, the test was administered in two core subjects, Mathematics and Social Studies. In this study, test items and sets of questionnaire and administered pretest were developed in the last year. In this year, the NAEA was administered with the adjusted test items and questionnaires and the results was analyzed and would be reported to the public. NAEA was developed on the basis of national curriculum, especially of the nature and objectives of subject curriculum in Mathematics (and also Social Studies). In the framework of assessment, we set up four differentiated levels of student achievement: 'under basic', 'basic', 'intermediary', and 'advanced'. Here 'the intermediary level' means the level of educational achievement in which students can understand average content of subject curriculum. 'Advanced level' indicates the level of educational achievement in which students master all the content of subject curriculum and apply basic concepts and principles to a variety of situations. 'The basic level' means the level of educational achievement in which students do not achieve the intermediary level. Students who do not understand average content of subject curriculum are classified as belonging to the basic level. Finally, this study would explain how to administer and analyze the test in the future. The test result was analyzed to report students' educational achievement according to regions, content areas, behavioral characteristics, and etc. This study would show how to report test result\ulcorner and how to set up students' academic achievement.

• Knowledge Management Research
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• v.5 no.1
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• pp.39-56
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• 2004

Mergers and Acquisitions(M&A) have long played an important role in the growth of firm. M&A has been considered a effective strategy for Korean government to restructure industry. Previous studies provided mixed results on the synergy effect of M&A This study provides investigation on 39 mergers occurred over the sample period from 2000 to 2001. In this study, event study methodology arc used to calculate abnormal return(AR) and cumulative abnormal return(CAR) based on mean-adjusted model. The testing period of this study from date -30 through date +30, where date zero is the date of the first public announcement of the merger. The empirical results in this study can be summarized as follows. First, the return rates of KOSDAQ registered firms with M&A appears higher than that of KSE listed firms. This means that public announcement of M&A is more influential on stock price for KOSDAQ registered firms than KSE listed firms. Second, The difference between actual merging price and fair value is significant in KSE listed firms and KOSDAQ registered firms. This means that the investors take M&A of KOSDAQ registered firms as a good news. Third, the impact on the market prices of merging firms take place after the first public announcement of the merger in KSE registered firms. But the impact on the market prices take place not only merging firms but also merged firms in KOSDAQ registered firms. This result shows that the investors recognize a M&A is a strategy of technology transfer in small & venture business.