• Journal of Preventive Medicine and Public Health
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• 제30권2호
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• pp.293-307
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• 1997

In Korea, sudden deaths of middle-aged and older male workers who are the responsible persons at home as well as workplace, have aroused social concern. Besides, U. N. has reported recently that mortality of Korea male in 40-50's was one of the highest among newly developed countries in 1992. Not much is, however, known about the nature of the work contributing to the mortality of different groups of workers. Therefore, this study was done to examine mortality of public servants, comprising about 5% of all the employed in Korea, according to their job titles and grades. The datas of 1753 official deaths, comprised 323 (only disease-oriented deaths) applicants of survivors' compensation, were used to examine age-adjusted Standardized Mortality Ratios(SMRs) according to their job titles, grades, tenures and cause of deaths. Controlling age and sex difference was conducted using 26,950,481 general population, 95,340 general deaths and 864,560 working public servants. All the groups were aged 20-64, who were being observed January - December in 1993, at the same time. Results and discussions are as follows. 1. SMRs standardized by general population was significantly low (SMR 44.9 CI 42.8-52.7) for all job titlses. Of public servants, 90.0% was graduated from high school, although 17.5% in general population. The distinction of social status such a education may produce a strong healthy worker effect. Besides, SMRs for different tenure groups showed a steady increase as tenure increases. This suggests that the magnitude of healthy-worker effect may be greater with increasing tenures. 2. SMRs standardized by own public servants was significantly elevated for work-men(SMR 121.0, CI 110.2-132.6) in solitue. When SMRs for different grade, of work-men was examined, 9th(SMR 124.2, CI 104.4-146.7) and 10th(SMR 137.9 CI 120.8-156.8)grade, lower grade in workmen, showed significantly elevated SMRs. Of workmen, 57.0% were graduated from high school and 50.1% in 9th grade, as well. These mean that low economic states made up social class, education may increase mortality rate. 3. Of SMRs according to all causes of death, only policemen on 'cause of death related hypertensive disease'(SMR 282.5, CI 121.6-556.7) was significantly high except for' cause of death related other signs, symptoms and ill-defined conditions'. 4. When SMRs on cause of death related hypertensive disease for different grade of policemen was examined, senior policemen(SMR 241.9), in charge of the front service, showed elevated SMR, in spite of statistical no significance. Especially, the working hour of senior policemen is quite long and also the work schedule is even more irregular for policemen. The results of this study showed that mortality for different jobs differed, and it differed also for different grades in the same job. This difference in mortality may reflect the difference in the nature of job contents, and further studies are warranted to elucidate which job characteristics are responsible.

• Journal of Preventive Medicine and Public Health
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• 제32권3호
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• pp.415-420
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• 1999

Objectives: We investigated the effects of changes in obesity and life style factors, such as cigarette smoking, alcohol drinking, and exercise, on the changes in blood pressure and serum cholesterol among Korean men. Methods: This study included 7,205 healthy male employees in the steel manufacturing industry. Each subject underwent health examination in 1994 and was re-examined in 1997. The study subjects were classified into four categories, according to changes in body mass index (BMI) (loss; stable; mild gain: severe gain), cigarette smoking (quitter; nor-smoker; smoker continued; smoker started), alcohol drinking (quitter; non-drinker; drinker continued; drinker started) and exercise (more exercise; continuous regular exercise; continuous irregular or no exercise; less exercise), respectively. We evaluated the relationship between the categories of change in those independent variables and the changes in blood pressure and serum cholesterol, adjusted for BMI in 1994 and age by analysis of variance. Results: The change in systolic blood pressure was positively associated with the changes in BMI (p<0.001) and drinking (p=0,001), but negatively with smoking (p=0,004), compared to the first category of each independent variables. The systolic blood pressure was significantly less increased in the continuous smoking group than quitter or hon-smoker. The changes in diastolic blood pressure and serum cholesterol appeared to have statistically significant linear relationships only with the change in BMI. The change in exercise showed a marginal significance with diastolic blood pressure (p=0.088). Conclusions: These prospective data emphasize the importance of obesity as a determinant of the changes in blood pressure and serum cholesterol. In addition, the changes in smoking and drinking habits can affect systolic blood pressure.

• 보건교육건강증진학회지
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• 제28권4호
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• pp.15-25
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• 2011

Objectives: The present study examined whether smoking rate has declined in 1992-2006 and who the high risk groups were on industry classification and employment type. Methods: Data from 91,263 persons aged 25-64 years were analyzed from three rounds of the Social Statistical Surveys of Korea between 1992 and 2006. Industry indicators were divided by the 9th Korean Standard Industrial Classification. Age-adjusted prevalence of smoking was calculated. Prevalence ratios(PR) and differences(PD) were estimated using log-binomial regression analysis. Results: Age-adjusted prevalence of smoking decreased between 1992 and 2006, specially the smoking prevalence of regular employees decreased most. PD in age-adjusted prevalence of smoking were the biggest between regular and daily employees. PR of the temporary employees', daily employees', self-employed persons' in order was wider than that of regular employees. PR increased significantly increased between 1999 and 2006 for those in manufacturing, construction, wholesale & retail trade, service industries. Increases in PR(regular/irregular) for women in service industry were statistically significant. Conclusions: Despite reducing overall cigarette smoking rates in males, the smoking rate was not reduced equally by industry classification and employment type in both genders. More adjustable antismoking policies and consideration of employment type are requested to reduce inequalities in smoking.

• 한국기계가공학회지
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• 제5권2호
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• pp.49-55
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• 2006

In the consideration of the problem occurred by certain return bender brazing welding works that depend only on handworks, the automatization of the whole production line is impossible due to the high dependency of skillful workers. In addition, it is difficult to establish a standardization due to the various heat exchanger model and irregular amount of orders, and the fault reduction is also impossible due to the severe difference in brazing conditions. It is necessary to develop a method, which quantitively analyzes the problem existed in this manual brazing welding of return benders and technically solves that problem, and to lead the improvement of the productivity and cost reduction in order to increase the business competitive power. Then, this will contribute the technical development of automatic welding for Korea's heat exchanger businesses. Thus, this study develops an automatic technology, which automatically controls the flame strength using digital control methods, for various models and produces a sample model. It is possible to increase the productivity and produce uniformed and qualified products by solving the problem existed in manual processes using the developed automatic return bender brazing system. In addition, the brazing condition can be automatically controlled according to the model and line speed, and such an economical operation can reduce the production cost. The developed system is expected to future applications not only heat exchangers in the field of refrigeration and air conditioning, but also other various industrial fields that apply heat exchangers, such as car and boiler industries.

• 토지주택연구
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• 제8권4호
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• pp.223-232
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• 2017

The purpose of this study is to identify the supply status and planning trend of North Korean housing through analysis on the North Korean architecture specialized media data. The flat composition is changing and the living room is becoming the center of the houses. Also, in the urban areas, the standard apartment type is four apartments in a row and the plan form is getting diversified into circle type, Y type, and irregular type. On the other hand, in the rural areas, two houses in a row and single house are typical and the change in planning scale and space structure are not substantial. Since the 2000s, design changes have been made to emphasize the third dimensional structure of buildings such as the elliptical houses and L-shaped houses. Furthermore, 8~10 households are located on one floor which leads to the tendency of the building enlargement. In terms of house size, a square concept was introduced to replace the initial 2~3 room concept and the basic module of the room planning the 3 room house based on $3m{\times}3m$. However, there seems to be no standard house size, and the house size may differ depending on the social classandregion. In the early 1980s, when there was focus on the apartment complex construction, the high-rise apartment buildings of 30~40 floors was planned. However, during the Pyongyang redevelopment project, apartments of more or less than 10 floors were built and row-houses of more or less than 4 floors were built. In terms of the complex scale, a lot of small complexes of around 300 households are emerging after 2010. The construction projects are mainly limited to specific regions such as Pyongyang and Samjiyeon, and also limited to specific classes such as the workers and soldiers initially and the scientists lately. In addition, living boundary composition and ancillary facilities for sufficient green area ratio securement and the people of North Korea are maintained consistently. In recent years, the specialized floor planning such as solar house and the house for the disabled people, framework houses for redevelopment business, and multi-storied house construction technology are also emerging.

• 감성과학
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• 제17권2호
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• pp.85-90
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• 2014

본 연구에서는 업무스트레스 관리를 위해 호흡과 심장박동간의 상관관계를 이용한 최적 호흡법을 유도하고 반복 훈련을 통해 사용자의 건강을 자가 관리하는 시스템을 개발하였다. 일정한 호흡은 심장의 항상성을 유지할 수 있도록 도움을 준다. 심장의 항상성 유지를 통해 업무스트레스 자극으로 인한 심장 리듬의 변화를 빠르게 안정시킬 수 있다. 사람은 개인에 맞는 고유한 호흡리듬을 가지고 있기 때문에, 최적 호흡리듬을 반복적으로 훈련하는 것을 통해 심장의 항상성을 높일 수 있다. 본 시스템은 개인에 맞는 최적 호흡리듬을 찾아서 이를 반복적으로 훈련할 수 있는 시스템을 개발하였다. 그리고 업무스트레스가 높은 콜센터 직원들을 대상으로 검증실험을 실시하였다. 검증실험 결과 자신의 맞는 호흡주기를 사용하여 호흡을 하면 심장의 반응이 안정성을 보이고 부교감이 활성화 되는 것을 확인할 있었다. 개발한 시스템을 활용하면 감정노동자들 중에서 콜센터 상담 업무스트레스를 저감시킬 수 있을 뿐만 아니라, 이를 통한 업무효율증가와 개인의 건강관리에도 많은 도움을 줄 수 있을 것으로 예상된다.

• 대한조선학회논문집
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• 제45권6호
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• pp.611-619
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• 2008

In most shipyards Floating Dock-gate System is adapted for dry docks. For the safe launching of ships in dry docks, smooth operation of dock-gate must be guaranteed. So it is very important to grasp its behavior in waves for securing the high productivity and the safety of workers. Its seakeeping ability was estimated numerically at the floating conditions and the free roll decay and the seakeeping model tests of dock-gate was carried out with bilge-keels of 3 different widths which have a scale of 1 to 20. More than 20% decrease of roll motion was observed in irregular beam seas by applying a bilge-keel system to the dock-gate that is long and narrow.

• 한국항해항만학회지
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• 제44권6호
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• pp.534-540
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• 2020

승선 환경의 폐쇄성과 이사회성, 선내 규율의 엄격함 등으로 청년들은 선원직을 기피하고 있다. 우리나라는 승선근무예비역제도라는 특수한 제도가 존재해 청년들을 선원직으로 유인하고 있지만, 이 제도마저 존립이 위태롭다. 최근의 선원 고용유형은 선박관리회사로부터 고용되어 선사에 파견되는 비정규직 형태가 대부분이다. 선박관리회사(SM)와 선원 간에 임시 고용계약을 맺고, SM이 선사에 선원을 파견하는 비정규직 고용형태가 유행하고 있다. 선원직 매력도가 떨어지고 있는 상황에도 2018년 발표된 국가 해운재건 5개년 계획에는 선박과 화물의 확보 방안만 담겨 있다. 이 논문의 핵심 내용은 이항로짓모형을 이용해 선원의 고용형태 결정요인을 분석하는 것이다. 분석 결과, 선원의 최종학력이 고용형태를 결정하는 요소로 나타난 반면, 소속선사 유형, 승선 선종, 소속 선박관리회사 유형, 근무 분야, 해기사 면허 소지 여부 등은 선원 고용형태 결정에 유의미한 변수가 아닌 것으로 나타났다.

• 한국BIM학회 논문집
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• 제10권4호
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• pp.32-39
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• 2020

In recent years, the construction industry is getting bigger and more complex, so it is becoming difficult to acquire point cloud data for construction equipments and workers. Point cloud data is measured using a drone and MMS(Mobile Mapping System), and the collected point cloud data is used to create a 3D digital map. In particular, the construction site is located at outdoors and there are many irregular terrains, making it difficult to collect point cloud data. For these reasons, adopting a noise reduction algorithm suitable for the characteristics of the construction industry can affect the improvement of the analysis accuracy of digital maps. This is related to various environments and variables of the construction site. Therefore, this study reviewed and analyzed the existing research and techniques on the noise reduction algorithm. And based on the results of literature review, performance evaluation of major noise reduction algorithms was conducted for digital maps of construction sites. As a result of the performance evaluation in this study, the voxel grid algorithm showed relatively less execution time than the statistical outlier removal algorithm. In addition, analysis results in slope, space, and earth walls of the construction site digital map showed that the voxel grid algorithm was relatively superior to the statistical outlier removal algorithm and that the noise removal performance of voxel grid algorithm was superior and the object preservation ability was also superior. In the future, based on the results reviewed through the performance evaluation of the noise reduction algorithm of this study, we will develop a noise reduction algorithm for 3D point cloud data that reflects the characteristics of the construction site.

• 드라이브 ㆍ 컨트롤
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• 제17권4호
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• pp.23-30
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• 2020

Driving on irregular and inclined roads using agricultural machinery such as spraying machines or trucks in orchards causes farmer casualties associated with the overturning of agricultural machinery. In addition, the harm to agricultural workers caused by the excessive inhalation of the scattered pesticide frequently occurs during pest control processes. To address these problems, we introduced precision agricultural technology that could selectively spray pesticides only where the fruit is present by recognizing the presence or shape of the fruit in the orchard. In this paper, a 16-channel LIDAR (VLP-16) made of Velodyne was used to identify the shape of fruit trees. Solenoid valves were attached to the end parts of 12 nozzles of the orchard spraying machine for on/off control. The smart spraying machine implemented in this way was mounted on a vehicle capable of autonomous travel and performed selective control depending upon the shape of the fruit trees while traveling in the orchards. This is expected to significantly reduce the amounts of pesticides used in orchards and production costs.