• 한국표면공학회:학술대회논문집
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• 한국표면공학회 1999년도 추계학술발표회 초록집
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• pp.15-15
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• 1999

In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

• 대한한방소아과학회지
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• 제30권2호
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• pp.31-46
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• 2016

Objectives In this study, the effects of Ja-eum-gang-hwa-tang (JGT) on the increase in airway epithelial mucosubstances of rats and ATP- or PMA- or EGF- or TNF-${\alpha}$-induced MUC5AC mucin production and gene expression from human airway epithelial cells were investigated. Materials and Methods Hypersecretion of airway mucus was produced by exposure of $SO_2$ to rats for 3 weeks. The effect of orally-administered JGT for 2 weeks on increased epithelial mucosubstances from tracheal goblet cells of rats was assessed by using histopathological analysis after staining the epithelial tissue with Hematoxylin-eosin and PAS-alcian blue. Possible cytotoxicity of JGT was assessed by investigating the potential damage on kidneys and liver functions by measuring serum GOT/GPT activities and serum BUN concentration of rats and the body weight gain during experiment. Also, the effect of JGT on ATP- or PMA- or EGF- or TNF-${\alpha}$-induced MUC5AC mucin production and gene expression from human airway epithelial cells (NCI-H292) were investigated. Confluent NCI-H292 cells were pretreated for 30 min in the presence of JGT and treated with ATP ($200{\mu}M$) or PMA ($10ng/ml$) or EGF ($25ng/ml$) or TNF-${\alpha}$ (0.2 nM) for 24 hrs to assess the effect of JGT both on ATP- or PMA- or EGF- or TNF-${\alpha}$-induced MUC5AC mucin production by using enzyme-linked immunosorbent assay (ELISA) and on gene expression by the same inducers using reverse transcription-polymerase chain reaction (RT-PCR). Results (1) JGT decreased the amount of intraepithelial mucosubstances of trachea of rats. (2) JGT did not show any renal and hepatic toxicities, and did not affect body weights either. (3) JGT significantly inhibited ATP-, PMA-, EGF-, and TNF-${\alpha}$-induced MUC5AC mucin productions from NCI-H292 cells. (4) JGT inhibited EGF-, and PMA-induced expression levels of MUC5AC gene in NCI-H292 cells. However, ATP- and TNF-${\alpha}$-induced MUC5AC gene expression levels were not affected in NCI-H292 cells. Conclusions The result from the present study suggests that JGT might control the production and gene expression of airway mucin observed in various respiratory diseases which accompanied by mucus hypersecretion. Also, JGT did not show liver toxicity or impact on kidney functions. The effect of JGT should be further studied by using animal experimental models which can show proper pathophysiology of airway diseases.

• 의료법학
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• 제12권1호
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• pp.133-173
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• 2011

Since mid-1960s the reports from the Surgeon General, the World Health Organization, and other health experts state that there is no risk-free level exposure to smoking and secondhand smoke. Tobacco smoke is made up of more than 7,000 chemicals. Hundreds are toxic, and at least 70 are carcinogens. The chemicals in tobacco smoke reach smoker's lungs quickly every time smoker inhale causing damages immediately. Inhaling even the smallest amount of tobacco smoke can also damage smoker's DNA, which can lead to cancers. Smoking is responsible for more than 87% of lung cancers, but there are a host of other chronic diseases directly related to exposure to tobacco smoke. It's also a major cause of heart disease, stroke, aortic aneurysm, peripheral arterial disease and most of the other diseases. In the United States, each year with more than from 440,000 to 520,000 deaths caused by smoking and exposure to involuntary smoke. They conclude that smoking is the single most important source of preventable morbidity and mortality. The United States of America have about 60-year history of tobacco litigation. Tobacco litigation has been an important tool in tobacco control strategies aimed at limiting the activities of tobacco companies and providing redress to people who have become ill as a result of their use of tobacco products. Tobacco litigation is a kind of tort litigation. Quite often, as in the asbestos and other mass tort litigation episodes, tobacco litigation can play an educational role, warning the public about the magnitude of health risks that might otherwise be less clearly perceived. Tobacco litigation allows smokers, their families or other victims of smoking to sue tobacco companies in order to be compensated for the harm they have suffered. Potential benefits of tobacco litigation include compensation for smoking-related damages, strengthening regulatory activity, publicity, documents disclosure and changing tobacco industry behavior. And also tobacco litigation can limit the political activities of tobacco industry, protect human rights of smokers and non-smokers, increase burden to tobacco price-up and enhance the effects of law and politics in public health.

• 한국수자원학회논문집
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• 제39권10호
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• pp.881-890
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• 2006

SWAT 모형을 이용하여 대전 3대 하천 유역의 수문 분석 및 도시화에 따른 영향을 평가하였다. 물수지 분석결과에 의하면, 전체적으로 총 유출량 중 지하수 유출량이 44%정도, 중간 유출량이 6% 그리고 지표유출량이 50%이다. 도시화 영향 분석 결과 전체적으로 1975년에서 2000년까지 갑천유역의 약 5%가량의 도시화는 총 유출량의 변화에 있어서는 현저한 차이를 보이지 않았으나, 도시화 율이 32%정도 증가한 소유역의 경우 유출 성분 분석에서 첨두 유량의 경우 $25{\sim}66%$의 증가를 보였고, 지하수 유출량의 경우 $68{\sim}73%$의 감소를 확인 할 수 있었다. 그리고 도시화의 영향으로 토양수분량은 건기를 제외한 모든 시기동안 감소한 반면 침투량은 모든 시기동안 감소하였다. 도시화의 영향은 강우량이 적고, 증발량이 많은 갈수년에 더 크게 나타났다. 이 결과로부터 도시화의 영향으로 풍수기 동안의 홍수피해 폰가 및 갈수기 동안의 하천의 건천화 문제를 유추 할 수 있을 것이다. 결론적으로 본 연구에서 수행한 수문분석 및 도시화 영향분석 결과는 향후 대천 3대 하천의 생태하천복원을 위한 물순환 정상화 대책마련 및 하천의 유량확보방안 마련을 위한 기초자료로 사용될 수 있을 것이다.

• 한국농림기상학회지
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• 제18권2호
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• pp.65-73
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• 2016

RCP4.5와 RCP8.5 미래 기후 변화 시나리오자료와 참다래 궤양병 피해 예측 모형인 D-PSA-K, 미래 참다래 재배적지 지도를 활용하여 궤양병의 미래 피해를 예측하고 참다래 궤양병의 발생 변화의 경향성을 찾아 보았다. 병원 세균에 의한 감염이 충분히 있다는 가정 아래에서 RCP4.5와 RCP8.5 시나리오의 2020년대와 2050년대에서 궤양병의 최대이병주율은 제주도와 남해안 일부 지역을 제외한 대부분의 지역에서 75% 이상으로 나타날 것으로 예측되었다. 두 시나리오들 모두에서 월동기 저온 환경이 없다는 가정 아래에서의 참다래 궤양병에 의한 가지 피해량은 거의 모든 재배가능지에서 증가될 것으로 예측된 반면에 월동기 저온에 의한 가지 피해량 증가율은 거의 모든 재배가능지에서 감소할 것으로 예측되었다. 지역 및 시나리오별로 궤양병 피해의 증가 및 감소의 경향은 다르게 나타날 것으로 예측되었다. RCP4.5 시나리오에서 2050년대에 2020년대에 비하여 10% 이상 최대 이병주율의 증가가 일어날 것으로 예측된 참다래 재배 가능지는 전체 재배 가능지의 3.14%, RCP8.5 시나리오에서는 25.41%였다.

• 한국해양환경ㆍ에너지학회지
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• 제13권3호
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• pp.216-222
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• 2010

연안잠식방지를 위해 둑이나 방파제 등의 고형의 구조물을 사용하는 것은 건설과 유지를 위해 많은 비용을 필요로 한다. 그럼에도 불구하고 파랑에너지가 효과적으로 감쇄되지 않을 경우 이들 고형 시설의 효과는 기대에 미치지 못할 수 있다. 효과적인 파랑에너지 감쇄를 통한 연안잠식 방지를 위해 경제적이고 환경친화적인 유연한 방파제를 도입하였다. 이 방파제는 폐타이어묶음과 그물망으로 이루어지는데, 폐타이어묶음은 그물망의 위치를 유지하는 역할을 하고 파랑에너지의 감쇄는 그물망을 통하여 발생한다. 현장실험을 위하여 2009년 6월 10일부터 타이완의 타이난 지역에 있는 슈앙천 해안에 상기 시설을 길이 50 m 높이 2 m로 설치하여 운용하였다. 2009년 6월 19~22일의 태풍 린파와 8월 6~10일의 태풍 모라콧의 영향 아래에서 상기 설비의 효능을 조사하였다. 설비 주위로 0.5~0.8 m의 침적이 발생하여 연안잠식 방지에 상기 설비의 효과가 긍정적인 것으로 나타났다.

• 대한한의학회지
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• 제24권3호
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• pp.51-64
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• 2003

Objective : This study investigated the alteration of neural activity and effect of Yanggyuksanhwa-tang (Lianggesanhuo-tang) on cerebral ischemia of rats. Methods : Considering age-related impact on cerebral ischemia, aged rats (18 months old) were used for this study. Ischemic damage was induced by the transient occlusion of bilateral common carotid arteries (BCAO) with hypotension. Yanggyuksanhwa-tang (Lianggesanhuo-tang) was administered twice a day orally. Then alterations of neural activities in the brain of aged BCAO rats were measured by the [$^{14}C$]2-deoxyglucose autoradiography method. Results : The BCAO in aged rats led to significant decrease of neural activity in the whole brain. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) significantly attenuated the decrease of neural activity in the whole brain following BCAO ischemia. Treatment significantly attenuated the decrease of neural activity in the CA1, CA2, CA3, dentate gyrus of the hippocampus, activated barrel, barrel cortex, somatosensory cortex, cingulate cortex, caudate putamen, and medial septal nucleus following BCAO in aged rats. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) also significantly attenuated the decrease of neural activity in the anteroventral thalamic nucleus, ventral anterior thalamic nucleus, arcuate nucleus, posterior hypothalamic area, medial mammillary nucleus, lateral periaqueductal gray, dorsal raphe nucleus, interpeduncular nucleus, median raphe nucleus, and medial pontine nucleus. Conclusion : It can be suggested that Yanggyuksanhwa-tang (Lianggesanhuo-tang) has a neuroprotecuve effect on cerebral ischemia through the control of glucose metabolic rate and cerebral blood flow.

• 한국지반환경공학회 논문집
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• 제21권5호
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• pp.23-33
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• 2020

경제규모가 확장됨에 따라 급격히 증가한 폭발성 인화물질과 같은 위험물질 운송차량 사고로 터널과 같이 폐쇄적인 공간에서 피해사례가 증가하고 있다. 특히 도로터널의 경우, 장대화 추세와 도심부 환경를 보호측면에서 도심부 통과사례가 증가하고 터널통과 중 폭발과 같은 예상치 못한 극한 재난에 대한 구조물의 안전 확보는 매우 시급하다. 이와 같은 이유로 선진국에서는 이미 내폭에 대한 검토를 수행하고 있지만, 국내에서는 폭발 위험도에 대한 평가 및 대응책이 거의 전무하다. 따라서 본 연구에서는 도로터널의 폭발 안전성을 평가하기 위하여 도로를 운행하는 차량 가운데 폭발 하중이 가장 크다고 판단되는 비등액체팽창증기폭발(BLEVE)을 기준 폭발원으로 정하고, 폭발 시뮬레이션을 위해 등가TNT 폭발하중으로 전환하는 방법을 제시하였다. 또한, 도출된 폭발하중을 적용하여 터널에 대하여 다양한 변수를 가정하여 동적거동 시뮬레이션을 수행하여 터널의 폭발 안전성을 분석하였다.

• 한국지반신소재학회논문집
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• 제9권1호
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• pp.39-46
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• 2010

최근 도시에 근접한 매립장은 인구밀집 지역과의 근접성, 부지개발에 따른 경제적 가치급등 등의 이유로 활용 가능한 새로운 건설부지로서의 관심이 집중되고 있다. 그러나 대부분의 사용 종료된 매립장은 매립장 내에 침출수의 누출방지를 위한 차수시스템이 바닥 및 사면부에 존치되어 있으며, 상부 부지의 재활용 설계 시 침출수 집배수 및 차수시스템의 안정성 평가를 실시하여 차수시스템 손상에 따른 지하수 주변지역 오염을 방지하여야 한다. 일반적으로 사용 종료된 폐기물 매립장의 차수시설은 매립장 운영과정에서 폐기물 덤핑에 따른 충격하중, 장비하중, 장기적인 매립폐기물 하중으로 인하여 인장강도변화 및 불규칙한 침하에 의한 손상이 발생될 수 있다. 본 연구에서는 사용종료매립장 부지의 재활용 시, 침출수의 누출방지를 위하여 기존 차수시스템 안정성 평가에 대한 연구를 수행하였다. 기존 사용종료매립장의 차수시스템의 안정성 및 손상여부를 평가하기 위하여 굴착 샘플링 시료에 대한 인장강도 시험 및 현장 추적자 조사를 실시하였다. 현장시료에 대한 인장강도 시험 결과, 항복인장강도는 시방기준 및 현행 폐기물관리법 설치기준에 적정하였으나, 추적자 조사결과, 위생매립구간 차수쉬트의 손상이 확인되었다.

• 대한조선학회논문집
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• 제51권5호
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• pp.380-387
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• 2014

Piper Alpha disaster drew attention to the damage likely to arise from explosions and fires on an offshore platform. And great concerns have been increased to prevent these hazards. Blast wall is one of the passive safety systems; it plays a key part of minimizing the consequences. However, a buckling due to explosion loads is a factor which can reduce the strength of blast wall. The buckling often occurs between web and flange at the center of blast wall. This study aims to find a solution for reinforcing its strength by installing a flat plate at the spot where the buckling occurs. First of all, ANSYS finite element method is adopted to numerically compute the structural resistance characteristic of blast wall by using a quasi-static approach. Sequentially, the impact response characteristics of blast wall are investigated the effect on thickness of flat plate by using ANSYS/LS-DYNA. Finally, pressure-impulse diagrams (P-I diagram) are presented to permit easy assessment of structural response characteristics of stiffened blast wall. In this study, effective use is made to increase structural intensity. of blast wall and acquired important insights have been documented.