• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.940-941
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• 2015

LCD (liquid crystal display) industry is needed to goods of high reliability and is interested in products without harmful material. In this experiment, we made the LED backlight unit for Automotive-navigation. And for making this backlight unit we used to eight side emitting type white LEDs with 1W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14W power consumption and start up voltage time is under the15ms in the ambient temperature $-20^{\circ}C$.

• 한국지역사회생활과학회지
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• 제18권1호
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• pp.39-53
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• 2007

The purpose of this study was to determine the characteristics of an experimental protective clothing material with regard to comfort and isolation from the hazardous heavy metals produced in municipal waste incineration. An analysis was conducted on the total concentrations of heavy metals in some parts such as surface, middle layer, and interior for the treated fabric, and the untreated one, and working clothes. We conclude that the processed fabric with charcoal for working clothes showed the least exposure to heavy metals of the three. Working clothes worn by workers during waste incineration were much more contaminated than the untreated and treated materials. The material of working clothes could be chosen according to the function with regard to its original chemical characteristics, which are the proper results of the dyeing process. The processed fabric material has high degrees of moisture regain, thermal insulation, water vapor penetration, and antibacterial function; consequently, it is much more comfortable to wear. The fabric material proposed in this research contributed much more to blocking heavy metal concentrations (such as Cd, Pb, Cu, Cr, Zn, Mn) than did the fabric of working clothes at present. Consequently, we strongly suggest that the material of working clothes be upgraded by adopting the above-mentioned charcoal-processed fabric. Materials of working clothes must be improved to increase comfort and prevent harmful gas, flying dust, and heavy metals from permeating the fabrics.

• 소성∙가공
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• 제30권4호
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• pp.165-171
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• 2021

This study was conducted on the manufacturing method of high-strength aluminum bolts. We obtained the displacement-load information by tensile test of the Al 6056 raw material and the T6 heat-treated material and calculated the precise flow stress and fracture limit using repetitive finite element analysis for before and after heat treatment. We designed a multi-stage forging process for T6 heat-treated material, and calculated that the accumulated damage value does not exceed fracture limits by finite element method. We produced the prototype forgings without any harmful defects such as cracks and folding occurring. Bolts made of T6 heat treated material show 9.6%higher tensile strength than T6 heat treated material after wire drawing.

• 한국환경보건학회지
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• 제3권1호
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• pp.27-44
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• 1976

This study was carried out to evaluate the harmful factors in working environments and to investigate the labor productivity after improvement of environments, surveying 93 industrial establishments of 10 industries located in Youngdeungpo industrial area in Seoul. The results obtained were as follows: 1) The highest noise level of 125dB(A) was indicated at the rolling process of transport equipment manufacturing industry. 2) The best illumination level was shown in precise machinery industry and the worst was indicated in rubber products, metallic products and transport equipment manufacturing industries. 3) Thermal conditions were above threshold limit value (TLV) at more than two processes of all industries except printing industry. 4) The highest dust concentration was determined in textile and wearing manufacturing industry. 5) Organic solvents were detected at 52 processes in 93 industrial establishments and 33 processes of them showed higher than TLV. The results about harmful chemicals were as follows: a) sulfur dioxide ($SO_2$)was determined higher than TLV on welding process of metallic product manufacturing industry and heat treatment process of transport equipment manufacturing industry. b) Carbon monoxide (CO) concentration was 700ppm at heat treatment process of transport equipment manufacturing industry, indicating 14 times of TLV. c) vinylchloride concentration in the air of PVC raw material mixing process and PVC preparation process of chemical product manufacturing industry was determined higher than TLV. d) Hydrochloride (HCl) concentration in the air of wire expanding process of transport equipment manufacturing industry was determined higher than TLV. 7) Higher values of lead concentration than TLV were determined at lead welding metallic product manufacturing industry and type planting process of process of printing industry, $1.8mg/m^3$ and $0.3mg/m^3$ respectively. 9) 22, 968 of 52, 855 workers (i.e. 43.5%) in 93 industries were exposed to various harmful agents. 10) It was found that the improvement of illumination in electric apparatus manufacturing industry (from 20~40 lux to 420 lux) resulted in an increase in productivity of 6.5% per capita and a decrease in faulty products of 19%. 11) Improvement of environments using local exhaust ventilation system resulted in a decrease of harmful substances lower than TLV and an increase in productivity of 11.4%. 12) Improvement of shovelling tools based on ergonomics resulted in a reduction in energy expenditure of 25.3% and an increase in productivity of 32.2% per capita.

• 환경생물
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• 제34권2호
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• pp.91-96
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• 2016

본 연구에서는 동물플랑크톤인 Daphnia magna를 이용하여 유해조류인 Microcystis aeruginosa, Anabaena variabilis, Limnothrix planctonica에 대한 제어 가능성을 평가하였다. D. magna와 유해조류를 공생배양 시킨 경우, M. aeruginosa ($80.2{\pm}4.2%$), A. variabilis ($39.7{\pm}4.0%$) 그리고 L. planctonica ($25.9{\pm}10.9%$)의 순으로 조류 발생 억제효율을 보였다. 동물플랑크톤의 섭생에 의한 조류 제어 효과 이외에 D. magna의 대사/분비물질의 조류 제어 가능성을 확인할 수 있었다. D. magna를 배양한 배지를 유해조류 제어에 이용했을 때, M. aeruginosa와 A. variabilis에 대하여 각각 $24.9{\pm}9.9%$와 $8.9{\pm}4.0%$의 성장 억제효과를 확인할 수 있었다. 하지만, L. planctonica에 대한 성장 억제효과는 나타나지 않았다. 본 연구의 결과를 통하여 동물플랑크톤인 D. magna를 활용한 친환경적 유해조류 제어기술 개발이 가능할 것으로 판단된다.

• 한국안전학회지
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• 제21권2호
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• pp.150-157
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• 2006

새건물증후군이란 새로 지은 건물에서 생활하는 사람들에게 눈이 따갑거나 목이나 코가 아프거나, 두통, 구토, 피부발진 등 증상이 나타나는 것을 일컫는 말이다. 새집증후군 원인물질의 주요 성분으로는 건축 자재나 벽지, 페인트, 가구 접착제 등에서 발생되는 포름알데이드(HCHO)와 톨루엔 등 휘발성 유기화합물(VOCs: Volatile Oragnic Compounds), 부유 박테리아, 곰팡이, 바이러스 등이다. 새집증후군을 저감하기 위한 방법으로는 환기에 의한 방법, 오염물질이 없는 친환경 재료의 사용 및 재료의 처리를 통해 오염물질을 저감하고자 제거하는 방법이 있다. 본 연구는 이들 방법 중 건축 재료 위에 표면코팅처리를 함으로써 실내 공기질을 향상시키기 위한 것으로, 건물 내 표면 코팅 전후의 공기질을 분석함으로써 실내 거주환경을 안전하게 조성하는 데 그 목적이 있다.

• 한국응용과학기술학회지
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• 제14권1호
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• pp.45-52
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• 1997

It is the problem point of stability for this study to produce cosmetics and to occur in the circulation process, and specially in a case of alcoholic toilet water the precipitation materials to float on content materials has study on the solubility of perfume, and it has practiced in order to examine the problem point whether the raw materials of plastic vessel is or not harmful in content materials. In testing result, A study on stability of alcoholic toilet water is above all the precipitation materials which floats in content materials, and It is appeared by combination ratio to the raw materials of perfume, ethanol, solubilizer and refining water etcs, and in second the alkali degree which has gushed out of glass vessel can understand the thing that the change of PH is largely increased following to the passage of time, and in third the harmful component of content materials out of raw material in plastics vessel must certainly consider a stability and a safety in quality control of products.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.541-544
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• 2004

지식정보사회로의 변천은 우리의 삶을 보다 편리하고 윤택하게 해주고 있지만 미처 예상하지 못했던 부작용 또한 적지 않게 발생하고 있어 이에 대한 해결방안을 모색하는 것이 시급한 실정이다. 아직 인성이 발달되지 못한 청소년들이 정보통신망을 통해서 유통되고 있는 수많은 음란물과 폭력물과 같은 유해정보에 무방비상태로 노출되고 있는 것도 정보화사회의 대표적인 역기능 중의 하나라고 할 수 있다. 이 문제점 해결을 위해 본 논문에서는 사이트 상에서 제공되어지는 내용을 AC 머신을 이용하여 유해 단어를 추출하고 유해 정보 데이터베이스를 이용해서 유해 단어에 가중치를 부여했다. 그 결과로 유해 정보를 포함한 사이트는 90%의 차단률을 보여 효율적인 시스템으로 판명되었다.

• Journal of Yeungnam Medical Science
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• 제36권1호
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• pp.20-25
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• 2019

Background: The aim of this study was to evaluate the awareness of occupational hazards and personal protective equipment use among dental hygienists (DHs). Methods: A total of 271 self-administered questionnaires were obtained from 280 DHs working at dental hospitals or clinics in Daegu and Gyeongsangbuk-do, Korea. Results: The occupational hazards included work involving dust (94.1%), volatile substances (86.0%), noise (97.0%), and light-curing units (96.7%). The proportion of dental hygiene tasks that participants perceived as harmful were 42.4%, 51.7%, 9.2%, and 31.4% in the same order as above. The proportion of participants who used dust-proof masks during work involving dust was 1.1%. Those who wore gas-proof masks and gloves for work using volatile substances were 0.7% and 31.2%, respectively. Participants who used goggles for work involving light-curing units were 31.0%. None of the participants used ear plugs for work involving noise. A total of 22.9% of the participants recognized the Material Safety Data Sheet, while 79.7% had never been educated about harmful work environments. Conclusion: When compared to exposure status and perception of occupational hazards, the level of protective equipment use was very low. Extra measures to increase DHs' use of personal protective equipment are necessary.

• 한국산업보건학회지
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• 제17권1호
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• pp.63-70
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• 2007

This study investigated the current management staus of chemical substance information on Material Safety Data Sheets(MSDS) and Chemical Information Cards(CIC) provided by Korea Occupational Safety & Health Agency(KOSHA) and also researched the kind and the characteristics of chemical substance information provided in other organizations. MSDS DB in Korean provided on KOSHANET(which is Kosha website) is 50,802 in total, among whom are single chemical substances with 31,870 kinds(18,932%) and are mixed chemical substances with 31,870 kinds(62.7%). The number of visiting MSDS DB on KOSHANET for the search of chemicals was 2,049,806. The number has increased each year. The CIC provided for workplaces is all 542 kinds : 14 harmful substances subject to permission, 168 harmful substances subject to management, 360 KOEL(Korean Occupational Exposure Limits) establishment substances. MSDS internationally provided by organizations producing MSDS DB was written with 16 sections, which is suitable for the writing basis of American Standards Institute(ANSI) and International Organization for Standardization(ISO) and provided chemical substance information on more than 100,000 kinds in most organizations.