• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.32-42
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• 2004

Recently, plasma surface-cleaning or surface-etching techniques have been focused in respect of the decontamination of spent or used nuclear parts and equipment. In this study the removal rate of metallic cobalt surface is experimentally investigated via its surface etching rate with a $CF_4-o_2$mixed gas plasma. Experimental results reveal that a mixed etchant gas with about 80% $CF_4$-20% $O_2$ (molar) gives the highest reaction rate and the rate reaches 0.06 ${\mu}m$/min at $380^{\circ}C$ and ion-assisted etching dramatically enhances the surface reaction rate. With a negative 300 V DC bias voltage applied to the substrate, the surface reaction initiation temperature lowers and the rate increases about 20 times at $350^{\circ}C$ and up to 0.43 ${\mu}m$/min at $380^{\circ}C$, respectively. Surface morphology analysis confirms the etching rate measurements. Auger spectrum analysis clearly shows the adsorption of fluorine atoms on the reacted surface. From the current experimental findings and the results discussed in previous studies, mechanistic understanding of the surface reaction, fluorination and/or fluoro-carbonylation reaction, is provided.

• 상하수도학회지
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• 제28권3호
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• pp.265-276
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• 2014

In this study, we suggested 4 plans to reduce non-point pollutant sources in Dongcheon and analyzed their controlling effects by water quality modeling, XP-SWMM. To do this we identified the influx of non-point pollutant sources to the initial rainwater through the water quality survey in the river and analyzed the causes of them at major locations, and suggested 4 kinds of plans reducing non-point pollutant sources. Plans reducing the non-point pollutant sources through cleaning the industrial road around the river(plan A), through a separate treatment facilities like the gutter(plan B), through installing treatement facilities(plan C), or through combing plan B and C(plan D) were analyzed using XP-SWMM model. The analysis showed that plan A, B, C and D reduced non-point pollutant sources average 21.7 %, 24.7 %, 49.3 %, 56.7 % respectively. Therefore, the water quality pollution in Dongcheon due to the influx of non-point pollutant sources is considered to be reduced effectively though cleaning the road, installed at the exits of paddy or factory basins, invasion type facilities or equipment-type facilities.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.360-360
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• 2008

Steelmaking industry is widely known to use a lot of water and same amount of wastewater is generated. Although toxicity of wastewater from Steelmaking industry is low, it contains an amount of various organic materials and Fe-Oxides. It is important to recycle the wastewater because of water shortages and water pollution. In general, large-scale equipment is necessary to process the wastewater. On the other hand, superconducting high gradient magnetic separation (HGMS) system can process the wastewater in the small space. Superconducting HGMS system that had a purpose to purify the wastewater was assembled. Cryo-cooled Nb-Ti superconducting magnet was used for magnetic separator. This system can operate continuously because contaminated filters can keep on returning after cleaning. The various magnetic seeding reactions were investigated to increase the reactivity of coagulation. Filter cleaning system was developed to decrease the quantity of clean water. This research was supported by a grant from Korea Electrotechnology Research Institute, Republic of Korea.

• 한국멀티미디어학회논문지
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• 제14권5호
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• pp.632-641
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• 2011

본 논문에서는 반도체 생산 공정 중 클리닝 공정 설비에서, 웨이퍼의 장착 위치를 인식하는 영상 인식 시스템을 제안한다. 제안한 시스템은 웨이퍼의 위치 이탈에 따른 위치오차 발생 시 이를 클리닝 설비에 전달하여, 웨이퍼 클리닝 장비의 파손을 방지하여 시스템의 신뢰성과 경제성을 높이기 위한 것이다. 제안한 방법은 기존의 시스템에서 체스보드 형태의 캘리브레이터를 사용시 발생되는 오차를 줄이기 위하여 방사형 캘리브레이터를 디자인 및 제작하고 이의 매핑합수를 구하는데 있다. 제안한 시스템은 고 신뢰성과 고 정밀의 위치인식 알고리즘을 사용하여, 효율적으로 웨이퍼 인라인 공정에 설치함을 목표로 하며 실험결과 기존의 방법에 비해 충분한 허용 기준 내에서 오차를 검출해내는 좋은 성능을 보여준다.

• 한국컴퓨터정보학회논문지
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• 제27권11호
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• pp.115-121
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• 2022

표면실장기술(SMT)에서 솔더 크림을 바르는 장비인 스크린 프린터는 패드가 작아지면서 도포 불량이 많이 발생한다. 이를 해결하기 위해 최근에는 젯 프린터를 사용하고 있다. 그런데 젯 프린터 헤드에 적용하는 밸브의 끝단 노즐을 깨끗하게 청소하지 않으면 과납이나 오도포가 발생한다. 이를 방지하기 위해서는 노즐을 주기적으로 청소해줘야 한다. 본 논문에서는 젯 프린터의 안정적인 솔더 크림 도포를 위하여 기존 기술보다 더욱 안정적으로 청소하는 방법을 제시하였다. 이 방법은 35mm 폭의 무진천을 재단하여 롤 형태로 감아 놓고, 반대쪽에 DC 기어드 모터로 회전시켜 닦는다. 그 결과 약 2,000회 도팅 주기로 청소를 했을 때 노즐 표면에 솔더 페이스트가 남지 않고 잘 닦이는 것을 확인하였다.

• 문화기술의 융합
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• 제8권3호
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• pp.507-514
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• 2022

본 연구에서는 출산 경험이 있는 여성을 대상으로 젖병 세척기 사용 시 손목 회전 동작에서 나타나는 근활성도 및 세척 방법에 따른 세척 청결도, 사용성 평가를 비교 분석하고자 한다. 이를 위하여 자동 젖병 세척기와 수동 젖병 세척기 사용 시 전완근의 근활성도, 세척 청결도는 장비를 활용하여 정량 평가하였으며, 변인들의 효과 분석을 실시하여 다음과 같은 결론을 얻었다. 첫째, 근활성도는 자동 젖병 세척기가 수동 젖병 세척기를 사용할 때 보다 낮은 것으로 나타났다. 둘째, 청결도는 자동세척(정방향+역방향)시 세척력이 제일 우수한 것으로 판단되며, 그 다음으로 자동세척(정방향), 수동세척 순으로 나타났다. 셋째, 젖병 세척기 사용에 대한 사용성 평가는 자동 젖병 세척기가 수동 젖병 세척기에 비하여 높은 만족도를 보였다. 이러한 결론을 통해 자동 젖병세척기 사용에 대한 효과성을 입증함으로서 본 연구는 향후 제품 고도화의 기초자료로 활용할 수 있을 것으로 판단된다.

• 한국융합학회논문지
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• 제13권3호
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• pp.91-103
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• 2022

본 연구는 COVID-19 발생 전후에 작업치료를 수행하고 있는 작업치료사 101명을 대상으로 손 씻기, 개인 보호 장비 사용, 주변 환경 정리의 감염관리에 대한 인식과 수행을 비교하고자 설문조사를 실시했으며, 맨-휘트니 U 검정(Mann-Whitney U test), 크루스칼-왈리스 H 검정(Kruskal-wallis H test), 윌콕슨 부호 순위 검정(Wilcoxon signed-rank test), 피어슨 상관분석(Pearson's correlation coefficient)을 사용해 분석하였다. 그 결과, COVID-19 발생 이전보다 발생 이후에 감염관리 교육을 더 잘 받았고 감염성 질환의 경험이 낮은 것으로 확인되었다. 또한, COVID-19 발생 이전보다 발생 이후에 손 씻기, 개인 보호장비 사용, 주변 환경정리에서의 감염관리에 대한 인식 및 수행이 향상된 것으로 나타났다. 하지만 현재까지도 질병관리청에서 권고하는 흐르는 물에서 40초 이상의 손 씻기와 치료실 청소 및 치료 도구의 소독은 개선이 필요한 실정이다. 본 연구를 통하여 감염성 질환의 발생을 최소화하기 위해 감염관리 교육을 정기적으로 반복해야 하며, 향후 작업치료사를 대상으로 하는 감염관리 교육 및 후속 연구에서 활용할 수 있는 기초자료가 될 수 있을 것이다.

• 대한영양사협회학술지
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• 제23권2호
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• pp.180-191
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• 2017

The purpose of this study was to identity the probability of cross-contamination from the environment. For this, we examined foodservices at 20 universities/colleges for microbiological analysis of their working facilities and environment as well as their preventive equipment against cross-contamination. Seventy percent of the 20 foodservices were found to maintain one unified working area, which suggests high probability of contamination of food/utensils/equipment in the cooking area by pre-preparation or dish washing. According to the microbiological analysis, the hygiene acceptance ratio of working facilities in the clean zone was 70%, which was higher than the average 45% hygiene acceptance ratio of working facilities in the contamination operating zone. There was a significant difference in the total plate count (P<0.001) and coliform count (P<0.01), which demonstrates that work tables in the clean zone were in a good state compared to those in the contamination operating zone. In the contamination operating zone, refrigerator shelves had a high probability of cross-contamination. Regarding the floor surface and airborne microbes, cooking areas which should be maintained as clean zones had higher cross-contamination probability than those in the contamination operating zone. So corrective actions such as cleaning and sanitizing, keeping dry floors, lowered temperature and humidity, shoe disinfecting facilities, and checking concentrations, are necessary to manage floor surfaces and airborne microbes in the cooking area.

• KIEAE Journal
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• 제5권4호
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• pp.9-16
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• 2005

The purpose of this study is to analyze the safety issues with regard to architectural elements in housing. Causes of accidents and threats to health are reviewed for 'safety' aspects. Threats to health tend to draw more attention due to recent increase of SHS and its public perceptions. The majority of victims by accidents in residential houses are on juveniles aged under 14 in bathrooms and living rooms. Non-slip finish materials are recommended to floors for access and circulation and protective pads to furniture edges. Colored glass may increase the safety of the windows in the living room. Handles and non-slip mats will be a good addition for the safety. Human scale design of the kitchen system is mandatory and appropriate size of storages for hazardous equipment are to be provided. Passive air ventilation for better air quality by dwellers in residence is occasionally used whereas large-scale apartments provide mechanical ventilation to supplement the volume of fresh air. Since the internal air quality is proved one of the major causes of atopic and respiratory diseases, steady effort to achive better air quality utilizing appropriate materials, plants and equipment is mandatory. Frequent cleaning and the use of anti-fungus materials are necessary because House Dust Mites are believed to be one of main causes of such diseases.

• 한국정밀공학회지
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• 제21권10호
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• pp.26-33
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• 2004

Ultra precision grinding technology has been developed from the refinement of the abrasive, the development of high stiffness equipment and grinding skill. The conventional wafering process which consists of lapping, etching, 1 st, 2nd and 3rd polishing has been changed to the new process which consists of precision surface grinding, final polishing and post cleaning. Especially, the ultra precision grinding of wafer improves the flatness of wafer and the efficiency of production. Furthermore, it has been not only used in bare wafer grinding, but also applied to wafer back grinding and SOI wafer grinding. This paper focuses on the flatness of the ground wafer. Generally, the ground wafer has concave pronto because of the difference of wheel path density, grinding temperature and elastic deformation of the equipment. Wafer tilting is applied to avoid non-uniform material removal. Through the geometric analysis of wafer grinding process, the profile of the ground wafer is predicted by the development of profile simulator.