• 콘크리트학회논문집
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• 제15권3호
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• pp.504-511
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• 2003

Environmental noise at high intensities directly affects human health by causing hearing loss. Although scientific evidence currently is not conclusive, noise is suspected of causing or aggravating other diseases. Environmental noise indirectly affects human welfare by interfering with sleep, thought, and conversation. Noise emission from motorized vehicle includes power unit noise, tire/pavement noise and aerodynamic noise. Among them, tire/pavement noise is noise emission from interaction of the tire and road surface when the vehicle cruises over the surface of pavement. In general, portland cement concrete(PCC) pavement is known to create more noise than asphaltic surfaces though it has the advantage of durability and superior surface friction. However, the results of preliminary laboratory test showed exposed aggregate concrete(EAC) has and effect on reducing tire/pavement noise. Based on the laboratory test. pilot construction of exposed aggregate concrete pavement was completed and series of in-situ measurements were conducted for noise analysis including the pass-by noise measurement and the close-proximity method. Conclusively, it is expected that tire/pavement noise represent significant portion of noise levels at higher frequencies and it would be reduced on special textures of pavement such as exposed aggregate concrete.

• 한국컴퓨터정보학회논문지
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• 제21권11호
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• pp.135-139
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• 2016

This paper investigates the empirical implications. The research question of this study is to verify the influences of psychological and environmental factors toward performance satisfaction and durability of learning in E-Learning University. For empirical verification, a survey was conducted targeting 500 students in E-learning Universities. The results show that actional environment on academic satisfaction in learning is the most important factor followed by physical environment, internal motivation, and academic burnout. The effect of psychological factors on learning persistence was important in the order of academic vision, internal motivation, actional environment and physical environment. The effect of academic satisfaction on learning durability proved to be statistically significant. The results suggest that actional environment should be considered with top priority to increase the academic satisfaction. learning satisfaction, academic vision, and academic satisfaction to enhance students' intention to continue studies are important. Academic burnout has a negative effect on both academic satisfaction and learning persistence, suggesting that this aspect should be properly addresses. The effects of student background variables in E-learning were explored.

• 한국조경학회지
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• 제34권5호
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• pp.52-58
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• 2006

Wildlife roadkill is a serious problem for road planners and biologists concerned with traffic safety, species conservation, and animal welfare. The objective of this paper was to analyze the effect of land use on the frequency of mammal roadkills. This study took part in three steps. First, data for 1,279 road kills of nine species were collected by survey over 26 months on 107km of roads near the Mt. Jirisan area. Second, the type of land use near the roadkill points was analyzed, and the area of each land use within loom of the road was calculated using GIS. Finally, the question of whether the land use affects the Sequency of mammal roadkills was analyzed by determining the density of roadkill occurrences for each land-use type. The results of the study were as follows. First, the roadkill density of all species was highest near grasslands, especially natural grasslands. Second, when comparing forests and rice fields, roadkill densities of the Eurasian red squirrel, Siberian chipmunk and Korean hare were higher near the forests, while the densities of the raccoon dog, water deer and leopard cat were higher near rice fields. The results of this study could be an essential information source for mitigating the roadkill problem in Korea.

• Safety and Health at Work
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• 제12권1호
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• pp.108-113
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• 2021

Background: This study aimed to investigate the relationship between changes in employment status and new-onset depressive symptoms through a one-year follow-up of permanent waged workers. Methods: We analyzed the open-source data from the Korea Welfare Panel Study. Using the 2017 data, we selected 2,314 permanent waged workers aged 19 to 59 years without depressive symptoms as a base group. The final analysis targeted 2,073 workers who were followed up in 2018. In 2018, there were five categories of employment status for workers who were followed up: permanent, precarious, unemployed, self-employed, and economically inactive. Multiple logistic regression was used to determine the association between employment status change and new-onset depressive symptoms. Results: Adjusted multiple logistic regression analysis showed that among male workers, workers who went from permanent status to being unemployed (odds ratio: 4.50, 95% confidence interval: 1.19 to 17.06) and from permanent status to being precarious workers (odds ratio: 3.15, 95% confidence interval: 1.30 to 7.65) had significantly high levels of new-onset depressive symptoms compared with those who retained their permanent employment status. There were no significant increases in new-onset depressive symptoms of male workers who went from permanent status to being self-employed or economically inactive. On the other hand, no significant differences were found among female workers. Conclusion: Our study suggests that the change of employment status to precarious workers or unemployment can cause new-onset depressive symptoms in male permanent waged workers.

• 한국환경과학회지
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• 제31권11호
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• pp.923-931
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• 2022

The aim of this study was to analyze differences in the perception of Gangwon-do residents using a satisfaction survey. The residents were found to be most satisfied with sectors such as parks/green spaces, landscape, and public order; however, they were least satisfied with transportation, culture, sports, medical services, and welfare facilities. Additionally, among all the items in the satisfaction survey, job satisfaction was the lowest. When comparing satisfaction trends observed in the city to those of the county, the overall satisfaction of the county was found to be slightly higher. This result could be attributed to young people being underrepresented in this survey in conjunction with the greater policy-level support for middle-aged people by from the government and Gangwon-do. Therefore, it would be worthwhile to create policies that primarily support young people and to also to create high-quality jobs with stable pay and employment prospects. This could minimize the outflow of youth and even encourage their inflow to similar small provincial cities. In Southern region and Seorak region of Gangwon-do, the satisfaction with gap between house price and region was low, which might be related to the increased demand for real estate throughout this area.

• 한국환경과학회지
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• 제32권10호
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• pp.741-744
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• 2023

This study focused on high school laboratory research and the main purpose was to develop alternative additives for livestock waste and ammonia volatilization methods with high school students as participants and to provide information to business owners based on the results. Compared to the control groups, The bentonite and illite treatment groups had similar ammonia volatilization, pH, EC, and total nitrogen content. In particular, the alum and aluminum chloride mixed treatment group showed low pH and ammonia volatilization, and high EC and total nitrogen content for poultry litter. As a result, when focusing on high school laboratory research, the alum and aluminum chloride mixed agent treatment fulfilled its role as an alternative additive for ammonia reduction. In addition, this approach can be suggested as a method to solve difficulties in adapting to the field through a practical cooperative relationship with livestock farms.

• 한국산학기술학회논문지
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• 제18권11호
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• pp.282-289
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• 2017

경제동물에 대한 동물복지에 대한 관심은 전세계적으로 고조되고 있는 추세이다. 그러나, 국내 양돈농가는 경제성 등을 이유로 고려하지 않거나 미비한 도입으로 돼지 본연의 행동이 제한되고 있다. 따라서, 본 연구의목적은 일반적인 사육환경에 환경보조물의 제공이 육성돈의 행동특성에 미치는 영향을 구명하고자 실시하였다. 실험동물은 45두의 3원 교잡육성돈(요크셔${\times}$랜드레이스${\times}$두록; 평균체중, $33.35{\pm}5.5kg$)을 준비하였고, 완전임의배치법(randomized complete block design)에 의해 3개 처리구(대조구; 현수형 환경보조물, T1; 바닥형 환경보조물, T2)에 처리구당 3반복, 반복당 5두씩 반슬러리 돈방에 배치하였다. 현수형 환경보조물은 돼지의 어깨 높이에 현수하였고, 바닥형은 돈방의 가운데에 고정시켰다. 시험기간은 14일간 수행하였으며 시험종료일에 스트레스호르몬인 코티졸(cortisol) 농도를 분석하였고 행동특성은 1과 8일차에 촬영하였고 베가스 프로(Vegas Pro) 13.0 프로그램을 활용하여 및 분석하였다. 체중 및 일당증체량은 대조구와 처리구들간 차이가 없었다. 코티졸호르몬은 T2(25.28 ng/mL)에서 대조구(46.75 ng/mL)보다 유의적으로 낮았다(p<0.05). 1일차 행동 유형별 지속시간은 움직임과 공격 항목에서 대조구에 비해 처리구에서 유의적으로 낮았다(p<0.01). 8일차 놀이행동 지속시간에서 처리구2는 925.12초로 T1의 323.91초 보다 유의적으로 높았다(p<0.01). 반면에 처리구들에 비해 대조구는 움직이지 않는 시간이 많았다(p<0.01). 이러한 결과는 환경보조물 제공이 돼지간 공격성을 감소시키고 돼지의 행동을 활동적으로 만들어 돼지 본연의 행동요구를 충족시킬 수 있음을 시사한다. 그러나, 국내에서 환경보조물에 대한 연구는 미흡하므로 본 연구결과는 보조물을 이용한 동물복지에 대한 기초자료로서 활용 가능할 것으로 사료된다.

• 한국산업보건학회지
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• 제24권3호
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• pp.310-320
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• 2014

Backgrounds: Endotoxin, which found in the outer membrane of the gram-negative bacteria cell wall, makes up almost all of the lipopolysaccharide(LPS). When people are exposed to endotoxin,it can result in diverse health effects such as an airway irritation and inflammation, fever, malaise, bronchitis, allergic asthma, toxic pneumonitis, hypersensitivity lung disease. Cases among the elderly, children or pregnant can occur more frequently than a healthy adult if they are repeatedly exposed to the existing endotoxin. Therefore, we investigated and assessed the environmental characteristics associated with the airborne endotoxin concentration level in six hospital lobbies. Method: Endotoxin from indoor air in six hospital lobbies was measured by an area sampling method and analyzed according to American Society for Testing and Materials International(ASTM international) E2144-01. Total suspended particulate(TSP), carbon dioxide($CO_2$), temperature and humidity were also measured by using direct reading measurements or airborne sampling equipment at the same time. Environmental characteristics were appropriately divided into two or three groups for a statistics analysis. One-way analysis variable(one-way ANOVA) was used to examine a difference of the endotoxin concentration, depending on the environmental characteristics. In addition, only variables with p-value(p<0.25) were eventually designed to the best model by using multiple regression analysis. Results: The correlation analysis result indicated that TSP(p=0.003) and $CO_2$(p<0.0001) levels were significantly associated with endotoxin concentration levels. In contrast, temperature(p<0.068) and humidity(p<0.365) were not associated with endotoxin concentration. Levels of endotoxin concentration were statistically different among the environmental characteristics of Service time(p=0.01), Establishment of hospital(p<0.001), Scale of hospital(p=0.01), Day average people using hospital(p=0.03), Cleaning time of lobby(p=0.05), Season(p<0.001), and Cleaning of ventilation system(p<0.001) according to ANOVA. Finally, the best model(Adjusted R-square=72%) that we designed through a multiple regression test included environmental characteristics related to Service time, Area of lobby, Season, Cleaning of ventilation system, and Temperature. Conclusions: According to this study, our result showed a normal level of endotoxin concentration in the hospital lobbies and found environmental management methods to reduce the level of endotoxin concentration to a minimum. Consequently, this study recognized to be requirement for the management of ventilation systems and an indoor temperature in order to reduce the level of endotoxin concentration in the hospital lobbies.

• Annals of Occupational and Environmental Medicine
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• 제34권
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• pp.31.1-31.14
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• 2022

Background: This study aimed to investigate the characteristics of work-related musculoskeletal disorders (WRMSDs) in occupational disease claims and identify patterns of WRMSDs for each body part by industry and occupation. Methods: This study analyzed the raw data of occupational disease claims for musculoskeletal disorders deliberated by the Occupational Disease Decision Committee of the Korea Workers' Compensation & Welfare Service in 2020. The data was classified into 6 body parts with the highest numbers of occupational disease cases by using the complete enumeration data on principal diagnoses and 4 types of subdiagnoses in the raw data. The characteristics and approval rates of WRMSDs by body part, industry and occupation were examined and summarized. Results: A total of 13,015 occupational disease cases for WRMSDs were classified, and lumbar spinal (back) diseases accounted for the largest proportion of claimed diseases, followed by shoulder, elbow, wrist, knee, and neck diseases in a descending order. The occupations with the highest and second highest numbers of occupational disease cases by body part were found to be automobile assemblers and production-related elementary workers for the neck, school meal service workers and cooks for the back, construction frame mold carpenters and school meal service workers for the shoulder, elementary workers in mining and food service workers for the elbow, food service workers and automobile parts assemblers for the wrist, and ship welders and school meal service workers for the knee. Conclusions: This study examined the characteristics and approval status of WRMSDs by body part and occupation. Based on the study results, management strategies for the prevention of WRMSDs should be established regarding occupations with a high risk of WRMSDs for each body part.

• International Journal of Human Ecology
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• 제13권2호
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• pp.101-111
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• 2012

Children have become the target of intense and specialized food advertising efforts. This study examines the content of TV food advertising and discussed possible concerns from the perspective of children. A total of 102 ads were collected from two cable networks aimed at children. Most of the food ads used emotional appeals and did not provide information clues such as nutrition values. Ads with high sales pressure and celebrity endorsements appeared frequently and the ads for snack foods and high-carbohydrate bakery products were dominant. Understanding food ads can be a significant indicator to establish the orientation of consumer ad education and build educational programs appropriate for children. The issue that appears conspicuous in child targeted advertising and marketing is the childhood obesity and food advertising relation; subsequently, there is a need to evolve advertising that targets children into a positive educational information source.