• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1247-1248
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• 2013

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1251-1252
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• 2013

• 한국염색가공학회지
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• 제34권1호
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• pp.27-37
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• 2022

In this study, a study and interpretation of the spinning process in copolymerized aramid spinning was conducted. In order to proceed with the spinning process modeling and analysis, the spinning process was modeled through the physical property modeling of the spinning solution and the structural modeling of the spinneret, and structural stability and flow of the spinneret for this spinning were analyzed. After modeling the spinning solution and the spinneret in a virtual space, the pack pressure and flow rate when the spinning solution was discharged were simulated. Macroscopically, the structural stability of the spinneret was confirmed at the standard pack pressure (100 kg·f/cm²), and microscopically, the flow rate and pressure drop data of the spinning solution according to the L/D(Length (L)/Diameter (D)) value were analyzed. Based on the research and development of virtual engineering modeling and analysis, we present the possibility of changing the shape and mechanical properties of copolymer aramid fibers according to the spinning process.

• Journal of Preventive Medicine and Public Health
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• 제31권4호
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• pp.708-718
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• 1998

To investigate the effect of smoking and drinking habit on the health status in lead using industries, 2,785 male workers in lead using industries (7 storage battery industries, 7 secondary smelting and related industries, and 4 primary metal and other manufacturing industries) were selected for this study. This study was carried out as a part of periodic health examination. Selected study variables were zinc protoporphyrin in whole blood (ZPP), SGOT and SGPT for laboratory test. Questionnaire for lead related symptoms and smoking and drinking habit was provided to all the workers and filled up by themselves and reconfirmed by physician. The results obtained were as follows; 1. The overall smoking and drinking rate of study population were 69.8% and 73.6%, respectively. While the smoking and drinking rate of storage battery workers were 68.8% and 72.3%, those of secondary smelting industries and other industries were 66.0% & 66.4% and 74.6 & 80.3% respectively. 2. While the mean values of blood ZPP of lead exposed workers were significantly higher than other group, those of SGOT of storage battery workers were significant higher than other worker. But there were no differences of mean values of other variables. 3. Smoking habit did not affect on the mean value of blood ZPP of workers in special health examination group, but there were significant differences of blood ZPP and SGOT between drinker and non-drinker. 4. Symptom prevalence of lead exposure were higher in drinking and smoking group than non-drinking and non-smoking group. 5. In multiple regression analysis of the total lead related symptoms, blood ZPP, SGOT, and SGPT as dependent variable, respectively, and age, work duration, blood ZPP, pack year and amount of alcohol drinking as independent variables, work duration, pack year, amount of alcohol drinking, age contributed to total symptoms; and age, work duration, pack year contributed to blood ZPP; and age, amount of alcohol drinking, work duration contributed to SGOT; and pack year contributed to SGPT.

• 한국해양공학회지
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• 제32권3호
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• pp.177-183
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• 2018

This study simulated ice load and the motion response of a moored semi-submersible rig in pack-ice conditions using a finite element method. Ice flows of random size and shape were modeled, and interactions for ice-sea, ice-structure, ice-ice were simulated using a simplified method. Parameters for the simplified method such as drag force coefficient and the pressure-penetration relation were obtained based on the result of detailed analysis using the coupled Eulerian-Lagrangian method. The mooring lines were modeled by spring elements based on their stiffness. As a result of the simulation over 1,400 seconds, the force and motion response of the rig were obtained and validated using discrete elements and compared with the results found by the Krylov State Research Centre.

• 한국응용과학기술학회지
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• 제29권4호
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• pp.585-593
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• 2012

역상 HPLC에 의한 polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 80의 ethylene oxide(EO)분리 및 간편하고 빠른 정량분석 방법을 개발하였다. 분석조건으로 분리관은 YMC Pack Ph ($250mm{\times}4.6mm$ i.d., $5{\mu}m$) 과 Phenomenex C4 ($250mm{\times}4.6mm$ i.d., $5{\mu}m$)을 사용하였고, 검출기는 ELSD를 사용하였으며, 이동상은 water/acetonitrile의 기울기 용리에 의해 분석되었다. 이때 검량선의 상관계수($r^2$)는 $180.2{\sim}980.5{\mu}g/mL$ 농도 범위에서 0.997이상 이었고, 검출한계, 정밀성이 우수하였다. 이 방법은 olysorbates의 산화에틸렌 분리분석 및 간편하고 빠르게 정량분석 가능함을 보여 주었다.

• 한국자동차공학회논문집
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• 제12권6호
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• pp.103-110
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• 2004

The major trend in global automotive market is changing drastically in the way that a vehicle FECPS(Front End Cooling Pack System) is designed and manufactured as an assembly part. The system can encompass many functions, be assembled into a vehicle as a module, and reduce the production cost as well as time. The FECPS consists of an impact beam, an aluminum condenser and a radiator, a carrier and a cooling fan with a BLDC motor. In order to predict the performance of a FECPS accurately, it is essential to properly model the air flow field through various heat exchangers, such as a condenser or a radiator. In this study, the flow field of the system is measured by a PIV(Particle Image Velocimetry) system. The result is compared with that measured with multi-channel anemometer.

• Safety and Health at Work
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• 제1권2호
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• pp.140-148
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• 2010

Objectives: Determining the work-relatedness of lung cancer developed through occupational exposures is very difficult. Aims of the present study are to develop a decision tree of occupational lung cancer. Methods: 153 cases of lung cancer surveyed by the Occupational Safety and Health Research Institute (OSHRI) from 1992-2007 were included. The target variable was whether the case was approved as work-related lung cancer, and independent variables were age, sex, pack-years of smoking, histological type, type of industry, latency, working period and exposure material in the workplace. The Classification and Regression Test (CART) model was used in searching for predictors of occupational lung cancer. Results: In the CART model, the best predictor was exposure to known lung carcinogens. The second best predictor was 8.6 years or higher latency and the third best predictor was smoking history of less than 11.25 pack-years. The CART model must be used sparingly in deciding the work-relatedness of lung cancer because it is not absolute. Conclusion: We found that exposure to lung carcinogens, latency and smoking history were predictive factors of approval for occupational lung cancer. Further studies for work-relatedness of occupational disease are needed.

• 한국의상디자인학회지
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• 제24권1호
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• pp.35-43
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• 2022

This study aims to analyze the physical properties of non-woven fabric sheets, which continue to grow in the cosmetic market. Non-woven fabric sheets were used as specimens, and a total of 17 samples were analyzed. To evaluate the physical properties of the non-woven fabric sheet, the weight, tensile strength, surface properties, free swell absorption, and wet stiffness were tested. Through the results itw was determined that non-woven fabric sheets for mask packs should be manufactured considering fiber arrangement so that the weight is 40 g/m², and the tensile strength should be maintained near 12 kgf. In addition, it was confirmed that the material selection and process conditions should be adjusted so that the free swell absorption is at least 8 g/g, and the wet stiffness is 200 mg. Therefore, since the non-woven fabrics for the mask sheets can be used in various products depending on fabric composition, this study will be expected to be basic data for the continuous growth of the sheet-type mask packs coming to market.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1239-1240
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• 2013