• Korean Journal of Remote Sensing
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• 제39권6_2호
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• pp.1651-1669
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• 2023

Sea ice currently covers approximately 7% of the world's ocean area, primarily concentrated in polar and high-altitude regions, subject to seasonal and annual variations. It is very important to analyze the area and type classification of sea ice through time series monitoring because sea ice is formed in various types on a large spatial scale, and oil and gas exploration and other marine activities are rapidly increasing. Currently, research on the type and area of sea ice is being conducted based on high-resolution satellite images and field measurement data, but there is a limit to sea ice monitoring by acquiring field measurement data. High-resolution optical satellite images can visually detect and identify types of sea ice in a wide range and can compensate for gaps in sea ice monitoring using Geostationary Ocean Color Imager-II (GOCI-II), an ocean satellite with short time resolution. This study tried to find out the possibility of utilizing sea ice monitoring by training a rule-based machine learning model based on learning data produced using high-resolution optical satellite images and performing detection on GOCI-II images. Learning materials were extracted from Liaodong Bay in the Bohai Sea from 2021 to 2022, and a Random Forest (RF) model using GOCI-II was constructed to compare qualitative and quantitative with sea ice areas obtained from existing normalized difference snow index (NDSI) based and high-resolution satellite images. Unlike NDSI index-based results, which underestimated the sea ice area, this study detected relatively detailed sea ice areas and confirmed that sea ice can be classified by type, enabling sea ice monitoring. If the accuracy of the detection model is improved through the construction of continuous learning materials and influencing factors on sea ice formation in the future, it is expected that it can be used in the field of sea ice monitoring in high-altitude ocean areas.

• Women's Health Nursing
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• 제7권2호
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• pp.212-228
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• 2001

This is a cross-sectional descriptive correlation study that aimed to understand the relationship between the level of sexual contacts during the dates and psycho-social factors in teenage girls who have or had boyfriends. The purpose of this study was to describe the relationship between sexual contacts and self-esteem and self- assertiveness. The subjects of the study were 6,130 teenage girls who have or had boyfriends. They were selected convienently 12,733 teenage girls from 254 secondary schools located in 7 large cities and 9 provinces in Korea. A structured questionaire was used it included items one general characteristics, the levels of sexual contacts, self-esteem and self-assertiveness. Seven levels of sexual contacts were rated they were holding a hand, putting arms around each other's shoulders, kiss, french kiss, touching breast, petting genitalia, and sexual intercourse during the dates. Self-esteem and self-assertiveness were measured by the "Self-esteem scale" of Rogenberg (1971) and the questionaires developed by S. B. Chang et al(2000), respectively. The self-reported questionaires were collected from October 2, to October 28, 2000 and analyzed by using SPSS 10.0 Program. The data were analyzed by descriptive statistics, reliability, One-way ANOVA with Duncan method & Scheffe method. The results of the analysis were as follows. 1.An average Percentage of the respondents who have (46.1%) or had (53.9%) boyfriends was 48.1% (n=6,130) and the most common sexual contact during the dates was french kiss (26.7%, n=1,634). While 7.5%(458) of respondents had a sexual intercourse, 13.7%(842) of respondents didn't have any sexual contact during the dates. 2. Distribution of starting point of the first sexual contact demonstrates that 1,950 respondents (31.8%) held partner's hand at the first date and 1,367 respondents (22.3%) put arms around each other's shoulders at the 2nd or 3rd date. Sexual contacts such as kiss, french kiss, touching breast, petting genitalia, or sexual intercourse were experienced mostly at the later than the 10th date. However, surprisingly large number(1.7%) of respondents had genital contact and sexual intercourses at the first date. 3. The means of self-esteem and self-assertiveness socres of the respondents who have or had boyfriends are 27.43$({\pm}4.03)$ and 17.96$({\pm}2.55)$, respectively. The range of scores for self esteem was 10-40, 40 with most self esteem. The range of scores for self assertiveness was 7-21, 21 with most self assertiveness. 4. As sexual contacts proceeded, the means of self-esteem and self-assertiveness values decreased. In detail, the respondents having no or light sexual contacts (kiss, putting arms around each other's shoulder, holding a hand) had similar self-esteem values($p{\leq}0.05$). However, ones having relatively intensive sexual contacts (french kiss, touching breast) showed significantly lower self-esteem values($p{\leq}0.05$). Same trend has been obtained for self-assertiveness value. 5. The higher values of self-esteem and self-assertiveness values the respondents had, the later they started the moderate sexual contact (kiss, french kiss) during the dates. Interestingly, among the respondents having intensive sexual contacts (petting genitalia, sexual intercourse) during the dates, those who experienced the such contacts at the first date or later than 10th date have higher self-esteem and self-assertiveness values than one experienced the such contacts during the 2nd$\sim$9th dates, giving U-shape curve. 6. There was a significant relationship between self-esteem and self-assertiveness in girls who have or had boyfriends($P{\leq}.001$). In conclusion, the research shows that self-esteem and self-assertiveness values are significantly related with the sexual contacts of the teenage girls who have or had boyfriends. These results strongly suggest that proper sex education program for teenage girls should contain the program on improving the self-esteem and self-assertiveness. We believe that sex education program is the one of the best ways to prevent the unwanted sexual contacts and pregnancy of teenage girls.

• Korean Journal of Community Nutrition
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• 제10권5호
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• pp.654-667
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• 2005

To survey the different view points about food service programs among parents and teachers, 2 types of questionnaires, which consisted of attitude, perception, satisfaction and demand of the food service program in child education centers, were used. The data was collected from 2450 parents and 450 teachers who attended a child education center in 16 provinces, nationwide. SPSS was used for descriptive analysis and ANOVA test and $X^2-test$. The frinding results were as follows. 1. The average serving size of meal (lunch) were 80 meals per day and 167 meals per day at large institutions. Mean cost of snacks was 14,709 won per month and mean costs of lunch were 29,319 won per month. The mean price was not significantly different according to the scale of institution. The numbers of servings of lunch, morning snack and afternoon snack were 5, 3.4 and 3.5 times per week each. $56.4\%$ of the institutions served meals to children in classrooms, but the national/public institutions, which were attending elementary school, served meals in a dining place in the elementary school. 2. Teacher controlled serving portion size of snacks $(79.6\%)$ and lunch $(88.8\%)\;and\;30.1\%$ of teacher did not allow leaving lunch food. The ratio of knowing about preserved meals of the teacher who worked at a small institution was significantly higher than the teacher who worked at large institutions (p<0.01). 3. Between parents and teachers, several different view points about school lunch programs were detected. Most parents and teachers wanted that the school lunch to be fully cooked and served at the child education institution itself, but $12.2\%$ of parents and $14.4\%$ of teachers wanted a catering service. The teachers group preferred 'lunch box from home' and 'home partially prepared lunch' as an ideal meal serving type than the parent groups (p<0.01). And there were significantly different view points about price factors in school meals, teachers group highly answered that operating expenses must be added in meal prices. 4. The teacher groups' priorities of education activities during meal time were a significantly lower score than parents group in overall education activities. Teacher and parent groups pointed out that individual sanitation activities were most important of the education activities during meal time, but promoting good eating habits was the lowest score in both groups. 5. 'Improving taste and food quality' was most urgent in food service at child education centers, but there were significantly different view points between parent groups $(64.5\%)$ and teacher groups $(43.8\%)\;(p<0.05)$. They answered at a lower percent in 'employee qualified person' and 'cost control' point to improve food service, but there were also different opinions between the two groups (p<0.01). 6. As to the matter of the advantages and disadvantages of catering services, two group answered that the advantages of a catering service were 'convenience' and 'to solve facilities and labor problems', disadvantages were 'lower in food freshness' and 'sanitation problems'. There were also several different view pionts in catering services, the parents groups were more anxious about food sanitation than teachers. This study found several different view points about school food services among parents and teachers. To improve food services at child education institutions, there is a need to adjust the differences between the two groups through interactive communication channels and education and to employ dietitians as taking charge of adjusting roles between the two groups.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.3785-3791
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• 2016

Background: Previous studies have assessed the association between the Cytotoxic T-lymphocyte Antigen-4(CTLA-4) polymorphism with the risk of malignant bone tumor, but the conclusions were inconsistent. We aimed to clarify association of cytotoxic T-lymphocyte antigen-4 polymorphisms with malignant bone tumors risk by performing a meta-analysis. Materials and Methods: The databases including PubMed, EMBase databases and the Cochrane Library were searched to identify the eligible studies prior to January 30 2016. Odds ratio (OR) with 95% confidence interval (95%CI) were used to estimate the strengths of the association between the CTLA-4 polymorphism and the malignant bone tumor risks. The meta-analysis was performed by STATA 12.0. Results: Four individual studies with a total of 1003 cases with malignant bone tumor and 1162 controls were included in our meta-analysis. The results of meta-analysis on those data demonstrated that CTLA-4 +49G>A polymorphism was associated with the risk of Ewing's sarcoma and osteosarcoma strongly (A vs. G: OR=1.36, 95%CI:1.20-1.54, p=0.000; AA+AG vs. GG: OR=1.35, 95%CI:1.14-1.61, p=0.001; AA vs. GG: OR=2.24, 95%CI:1.67-2.99, p=0.000; AA vs. AG+GG: OR=2.00, 95%CI:1.53-2.62, p=0.000), but CTLA-4 -318C/T polymorphism was not associated with the risk of malignant bone tumor (C vs. T: OR=0.76, 95%CI:0.76-1.08, p= 0.262; CC+CT vs. TT: OR=0.70, 95%CI:0.41-1.20, p= 0.198; CC vs. TT: OR=0.69, 95%CI:0.40-1.19, p= 0.183; CC vs. CT+TT: OR=0.92, 95%CI:0.75-1.13, p= 0.419). Subgroup analysis showed that there are significantly positive correlations between CTLA-4 +49G>A polymorphism and increased risks of malignant bone tumors in large size of sample (A vs. G: OR=1.347, 95%CI: 1.172,1.548, p=0.000; AA vs. GG: OR=2.228, 95%CI: 1.608,3.085, p=0.000), Ewing's Sarcoma or Osteosarcoma (A vs. G: OR=1.361, 95%CI: 1.201,1.540, p=0.000; AA vs. GG: OR=2.236, 95%CI: 1.674,2.986, p=0.000), and PCR-RFLP or Sequencing(A vs. G: OR=1.361, 95%CI: 1.201,1.540, p=0.000; AA vs. GG: OR=2.236, 95%CI: 1.674,2.986, p=0.000), but CTLA-4 -318C/T polymorphism was not associated with the risk of malignant bone tumors in diagnosis, genotype method, and sample size (all p>0.05). Conclusions: CTLA-4 +49A/G variant was associated with an increased risk of developing the malignant bone tumors, such as Ewing's sarcoma and osteosarcoma. However, it failed to show the association between CTLA-4 -318C/T polymorphism and the risk of malignant bone tumors. Future large-scale studies remain to be done to confirm our conclusions.

• Proceedings of the Korean Environmental Health Society Conference
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.24-25
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• 2003

Lead is ubiquitous in the human environment as a result of industrialization. China's rapid industrialization and traffic growth have increased the potential for lead emissions. Lead poisoning in children is one of the most common public health problems today, and it is entirely preventable. Children are more vulnerable to lead pollution and lead in their bodies can affect their nervous, circulatory, and digestive systems. Children are exposed to lead from different sources (such as paint, gasoline, and solder) and through different pathways (such as air, food, water, dust, and soil). Although all children are exposed to some lead from food, air, dust, and soil, some children are exposed to high dose sources of lead. Significant sources of lead for China's children include industrial emissions (often close to housing and schools), leaded gasoline, and occupational exposure that occurs when parents wear lead-contaminated clothing home from work, burning of coal for home heat and cooking, contaminated food, and some traditional medicines. To assess the blood lead level in children in China, a large-scale study was conducted in 19 cities among 9 provinces during 1997 to 2000. There were 6502 children, aged 3-5 years, were recruited in the study The result indicates that the mean blood lead level was 8.83ug/dl 3-5 year old living in city area. The mean blood lead level of boys was higher than that of girls (9.1l ug/dl vs 8.73ug/dl). Almost 30 percent childrens blood lead level exceeded 10ug/dl. The average blood lead level was higher than that of in 1985 (8.83ug/dl vs 8.lug/dl). An epidemiological study was carried on the children living around the cottage industries recycling the lead from battery. Nine hundreds fifty nine children, aged 5-12 years, living in lead polluted villages where the lead smelters located near the residential area and 207 control children live in unpolluted area were recruited in the study. The lead levels in air, soil, drinking water and crops were measured. The blood lead and ZnPP level were tested for all subjects. The results show that the local environment was polluted. The lead levels both in the air and crops were much higher than that of in control area. In the polluted area, the average blood level was 49.6ug/dl (rang 19.5-89.3ug/dl). Whereas, in the unpolluted area, the average blood level was 12.4ug/dl (rang 4.6-24.8ug/dl). This study indicates that in some countryside area, some cottage industries induce seriously lead pollution and cause children health problem. For the introducing of unleaded gasoline in some large cities, such as Beijing and Shanghai, the blood lead level showed a declined trend since 1997. By 2000, the use of leaded gasoline in motor vehicles has been prohibited in China. The most recent data available show that levels of lead in blood among children in Shanghai decreased from 8.3ug/dl in 1997 to 7.6ug/dl in 1999. The prevalence rate of children lead poisoning (blood lead >10ug/dl) was also decreased from 37.8% to 24.8%. In children living in downtown area, the blood lead level reduced dramatically. To explore the relationship between gene polymorphisms and individual susceptibility of lead poisoning, a molecular epidemiological study was conducted among children living in lead polluted environment. The result showed that the subjects with ALAD2 allele has higher ZPP level, and the subjects with VDR B allele has larger head circumference than only with b allele. In the present study, we demonstrated that ALAD genotypes modify lead effects on heme metabolism and VDR gene variants influence the skull development in highly exposed children. The polymorphism of ALAD and VDR genes might be the molecular inherited factor modifying the susceptibility of lead poisoning. Recently, Chinese government pays more attention to lead pollution and lead poisoning in children problem. The leaded gasoline was prohibited used in motor vehicles since 2000. The government has decided to have a clampdown on the high-polluted lead smelters for recycling the lead from battery in countryside. It is hopeful that the risk of lead poisoning in children will be decreased in the further

• KDI Journal of Economic Policy
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• 제13권4호
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• pp.3-30
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• 1991

This paper examines Korea's exports of manufactures to the United States, Japan, and other OECD member countries in the 1974-89 period, focusing on the market share in the trade partners' imports. It decomposes the growth of exports into various effects, following the "constant-market-shares" analysis. For this purpose, the entire period is divided into three subperiods: 1974-78, 1978-83, and 1983-89. The paper also estimates a regression model of the market share determination, using the data of Korea's market share in U.S. imports. In the three subperiods under study, Korea's exports grew at different paces for varied reasons. The average annual growth rate was 28 %, 11 %, and 21 %, respectively. A large drop in the "competitiveness effect", that is, in the market-share growth rate, was mainly responsible for the decline in the export growth rate. The largest drop in the competitiveness effect was found in the light manufactures exports in the second period. The market share did not regain the rapid growth momentum. The main reason for the rise in export growth rate in the last subperiod was the "market-size effect"-a rise in the growth rate of the trade partners' imports. According to the regression results, high intensities in physical and human capital tended to lower the Korean manufacturing industries' market shares in the United States. This negative correlation was stronger in the case of human capital intensity, suggesting that Korea is relatively poorer in human capital endowment than in physical capital endowment when compared to the United States. This negative correlation between the market share and each of the two intensities became weaker overtime. This may be interpreted as the consequence of both physical and human capital accumulation which were faster than the labor force growth. Depreciation of the Japanese yen was estimated to have a negative influence on the Korean manufacturing industries' market share in the United States, and this negative influence became stronger each year in the 1980s. This seems to reflect the intensifying competition between the two countries' exports in U.S. import markets. The Heavy and Chemical Industry Policy of the 1970s, which promoted a number of selected industries by providing them with various incentives and inevitably discriminated against the rest of the industries, was estimated to have had strong negative effects on the export performance of the light manufacturing industries. This finding and the largest decline in the "competitiveness effect" -found in the light manufactures exports in the 1978-83 period-indicate that the Heavy and Chemical Industry Policy was mainly accountable for the drop in the export growth rate during the period. On the other hand, the rise in export growth rate during the subsequent subperiod was greatly impacted by the large scale exchange rate realignments of major currencies, especially by the appreciation of the Japanese yen, and other changes in international economic conditions.

• Journal of the Korean Dietetic Association
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• 제8권3호
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• pp.280-288
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• 2002

The purpose of this study was to investigate the operational characteristics of the contract-managed highschool foodservice and to analyze the factors to effect the menu price. The data was collected from 249 highschools in Seoul. The results are as follows; Those surveyed highschools were established as 1 national, 74 public, and 174 private institution. Highschools were classified as 176 academic, 66 vocational, and 7 specific purposed institution. Students were organized as 70 boys', 23 girls', and 41 coeducational highschools. Most highschool started contract-managed highschool foodservice from 1999 and the period of foodservice contract was most 3 years and the operation styles in food distribution were 96 classrooms, 105 dining halls and 17 classrooms combined dining halls. The scale of contract foodservice management companies was 63.1% small and medium and 36.9% large enterprises. The surveyed highschools had the average meal price 2,141 won per meal and they had 1,518 pupils on the register. The participating rate to the foodservice was 68.5%. The facilities investment cost of the contract foodservice management company was 179,204,230 won for private institutions and was 138,119,010 won for national&public institutions. The period of the contract was 3.22 years in private institutions, which was significantly higher than national&public institutions which showed 2.85 years. The commissary foodservice schools had higher facilities investment cost than conventional foodservice schools. Classrooms foodservice had higher participating foodservice rate than Dining halls. The investment cost for facilities showed high in order of girls', boys', and coeducational high schools, and the number on the register and the number participating in the foodservice showed high in order of boys', girls', and coeducational high schools. The number on the register showed the highest in academic and vocational schools, specific purposed institutions in sequence, and the number participating in the foodservice showed high in order of academic schools, specific purposed institutions and vocational. However, the participating foodservice rate showed high in specific purposed institution, academic and vocational schools in order, and the meal price, the investment cost for facilities showed high in specific purposed institution, academic and vocational schools in sequence. Regionally, the district south of Han river had the average meal price 2,266.13 won, which showed higher in the eastern part which had 2,033.33 won. The western part had the average investment cost for facilities of 233,331,060 won, and the central district 126,137,140 won. The number on the register showed 1845.68 in the eastern part and 1308.00 in Dong-Jak area, that had clear differences among areas. When the period of the contract went longer, the investment cost for facilities had a tendency to increase. The significant differences were existed among meal price, the investment cost for facilities, the number on the register, the number participating in the foodservice, and the participating foodservice rate. The investment cost for facilities had increased according to the number participating in the foodservice and the participating foodservice rate. And the large enterprises showed higher participating foodservice rate than the small and medium enterprises.

• Journal of Distribution Science
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• 제10권5호
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• pp.37-44
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• 2012

In this paper, we investigate several factors that affect the locational decision of discount stores by using previous studies on the marketing area and the location of commercial facilities. We selected 21 primary variables that are expected to influence the decision of store location and, by factor analysis, grouped them into five underlying factors. Among these, the demographic factor, which shows the potential purchasing power level, had the greatest impact on the locational decision for the store. However, we found individual stores positioned according to unique locational characteristics in addition to the demographic factor. It means that we have to additionally consider if the vicinity of the market is based on any physical properties. Many previous studies proposed four decision factors for store location: the economic factor, the demographic factor, the land utilization factor, and traffic factor. However, the fivefold factors-our distinctive contribution-are more concrete and persuasive according to Korean reality. We show that location preference is based on the following criteria: (1) the area is densely populated, (2) houses stand close together, (3) residents have a high income level, (4) road traffic is developed and easy to access, and (5) public transportation is well developed. The demographic factor has the greatest impact on the location of a discount store. The number of households has a greater relevance to the demographic factor than does the individual consumer. Second, discount stores relatively prefer places where houses are located close together because such places offer easy access to the market. Third, a place whose residents have a high income level will be preferred, with its large cars and excellent traffic conditions. Fourth, a location would be highly rated if the roads around commercial facilities are well developed and their accessibility is good. Finally, discount stores must be located close to bus stops because female consumers, including housewives-the most important customers-evaluate stores based on distance. In this research, the variable of consumer attitude and preference was excluded, and the location factors of discount stores were analyzed according to a microscopic view through physical spatial data. In the future, the opening of new discount stores based on the five factors indicated above will require a comparatively shorter time from the first project feasibility analysis. In addition, the result of our study can be applied to the field of public policy for constructing and attracting large-scale distribution facilities.

• Economic and Environmental Geology
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• 제54권5호
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• pp.535-547
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• 2021

Aggregate is an essential construction material, and the demand is increasing every year. Aggregate has different properties in each region, and it is difficult to supply it over long distances due to its quantity and weight. For the stabilization of aggregate supply and demand, regional aggregate resource surveys have been conducted since 1993 in Korea. In this study, an aggregate resource survey was conducted in Goyang City to understand the characteristics of aggregate distribution as part of the annual regional aggregate resource survey in 2020. Goyang City has a high mountainous area to the east, and the southwestern part shows a topography where a wide flatland develops. It has 18 small streams originated from the eastern mountainuos area and 1 large stream Han River. The drilling data shows that thickness of the Quaternary deposits tend to deepen toward the south. The aggregate reserves are relatively abundant, the depth of the aggregates are relatively deep. Changes in the depth of the Quaternary deposits and the amount of aggregate in Goyang are seems to be closely related to the activities of the Han River rather than the sedimentation characteristics from the upstream to the downstream of the small streams. This characteristics show a similar tendency to the distribution of aggregates in adjacent regions to the west coast in Korea. Therefore, the regions that close to west coast have a high probability of aggregate reserves around relatively large-scale streams flowing into the west coast.

• Journal of Korea Society of Industrial Information Systems
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• 제24권1호
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• pp.45-63
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• 2019

The number of domestic construction company is expanding every year while the construction workers' exposure to disaster risk is increasing due to technological advancements and popularity of high-rise buildings. In particular, the industry faces greater fatalities and severe large scale accidents because of construction industry characteristics including influx of foreign workers with different language and culture, large number of aged workers, outsourcing, high place work, heavy machine construction. The construction industry is labor-intensive, which is to be completed under given timeline and consists of unique working environment with a lot of night shifts. In addition, when a fixed construction budget is not secured, there is less investment in safety management resulting in poor risk management at the construction site. Taking account that the construction industry has higher accident risk rate and fatality rate, risky and unique working environment, and various labor pool from foreign to aged workers, preemptive safety management through risk factor identification is a mandatory requirement for the construction industry and site. The study analyzes about 8,500 cases of construction accidents that occurred over the past 10 years and identified risk factor by construction industry sector to secure a systematic insight for risk management. Based on interrelation analysis between accident types, work types, original cause materials and assailing materials, there is correlation between each analysis factor and work industry. Especially for work types, there is great correlation between work tasks and industry type. For reinforced concrete and earthwork are among the most frequent types of accidents, and they are not only high in frequency of accidents, but also have a high risk in categories of occurrence.