반도체 LD용 무반사 박막 제작에 관한 연구 ( Deposition of antireflection coatings on semiconductor laser diodes )

김효상,박홍진,황보창권,김부균,김형문,주홍로 대한전자공학회 1995 대한전자공학회 Conference Vol.1995 No.1

서울市 大氣汚染에 對한 氣候要素別 調査 硏究

金孝相 서울大學校 保建大學院 1973 公衆保健雜誌 Vol.10 No.1

In an attempt to evaluate the air pollution in Seoul area, the levels of sulfur oxides (mg SO₃/100 cm²/day) by lead peroxide candle method and the dust falls (ton/km²/mon.) by deposit gauge method were measured monthly at 25 points(4km²) in industrial, commercial, residential and green areas for three years from 1969 to 1971. The effect of weather factors on the pollution was studied with the meteorological data from the National Centural Meteorological Office. The results are followings; 1. Average concentrations of sulfur oxide were 1.092mg SO₃/100cm²/day in 1969, 1.171 in 1970 and 1.333 in 1971 and the total average of three years was 1.206(S.D. 0.522). 2. Average amount of dust falls was 22.2tons/km²/mon. in 1969, 23.6 in 1970 and 25.4. in 1971 and the total average of the three years was 23.7 (S.D 11.6). 3. The above data of air pollution was matched according to season and area and their correlationship to air pollution was analyzed by computser. (1) The ana1ysis has showed the highest concentration of sulfur oxide with 1.592mgSO₃/100cm²/day in winter and with 1.566. in industrial area. (2) Dust falls, however, has showed the heaviest with 29.9tons/km²/mon. in spring with 33.7. in road commercial area. (3) According to the correlationship between the air pollution concentration and the climatic elements which were checked simultaneously with pollutants, sulfur oxides were high with 1.464mg SO₃/100cm²/day when the atmospheric pressure was over 1.020 mb. and 1.592. when the air temperature was below 0.0℃. It was found that the concentration of air pollution due to sulfur oxide was high when the weather showed high atmospheric pressure at the time there were few cloudes in the sky and many hours of sunshine. It was natural from the view point of topography that Seoul showed the wind direction of west, west-west-north in winter and the wind direction in the winter season showed a significant effect on air pollution in the city area. Dust falls was heavy when the atmospheric pressure and air temperature was high and when the humidity was low and amount of clouds were few. The amount of dust falls was the highest with 26.4 tons/km²/mon. when the wind velocity was over 2.7m/sec. and was low when the amount of precipitation was almost daily and heavy. 4. Contribution rate (ESS/TSS : Explained Sum of Squares/Total Sum of Squaresx100) of climatic element effecting the air pollution during the study period was analyzed by Multiple Classification Analysis method (M.C.A) using the computer. The results are follows; 48.8% of sulfur oxide and 45.0% of dust falls due to the weather condition.

데이터마이닝을 활용한 이용자 맞춤 공공데이터 기상 정보 제공 Application

김효상,신인수,김기현,박희정 한국산업경영시스템학회 2014 한국산업경영시스템학회 학술대회 Vol.2014 No.춘계

[기획노트] 플레이티켓

김효상 공연과이론을위한모임 2020 공연과 이론 Vol.- No.80

주파수 간섭에 대한 분석 프로그램 개발에 관한 연구

김효상,최부귀 東亞大學校 大學院 2002 大學院論文集 Vol.27 No.-

Because the frequency interference is happened on all frequency band, wee have much interested in the frequency interference in case of dealing with wireless communication. Particularly, Car phone as well as FRI which is used in Microwave and a communication satellite is very complex and difficult. On this study, I will introduce the analytical program about the frequency interference by dealing with RFI that is happened on both a communication satellite network ad microwave communication network on the ground.

멀티미디어에 있어서 물체의 추적과 인식에 관한 프로그램 설계

김효상,최부귀 동아대학교 2001 大學院論文集 Vol.26 No.-

To remember the figures that we have seen is to store the figures of every moment. And when we remember of previous figures become more and more faint and then, the most recent figures will be able to remain strong in our memory. Finally, in order to pursue the figure that we see now, we must move our eyes to the direction that the previous figures can be most overlapped. By using this principles, we showed the pursuing and recognizing processes of moving figures on following display.

낙동강 수계 원수를 대상으로 조류 대응 막여과 시스템 검토

김효상,이상도,정경미,서선근,오영기 한국막학회 2016 한국막학회 총회 및 학술발표회 Vol.2016 No.11

기후 변화 및 상수원 오염 등으로 원수 내 조류 증식의 빈도가 높아짐에 따라 모래여과와 마찬가지로 막여과 정수처리 공정 운영에서도 문제를 유발할 수 있기 때문에 이에 대한 기술적 대응 방안이 수립되어야 한다. 특히 우리나라와 같이 계절적 구분이 뚜렷한 지역에서 조류는 수온에 따라 우점하는 조류의 종이 변화하여, 외형 적 형태 및 성상이 종별로 다른 조류의 특성을 감안한 대처 방안이 검토되어야 한 다. 본 연구는 낙동강 수계를 원수로 하는 500m3/d 규모의 파일럿 플랜트를 이용하여 계절별로 상이하게 유입되는 조류의 분류에 따라 겨울철 저수온 시기에 규조류가 번성할 경우 염기 역세정 방법을 적용하고, 여름철 시기에 남조류가 번성할 경우에는 분말활성탄으로 처리하는 조류 대응 막여과 운전 방법과 전처리 공정에 대해 검토하였다.

암호화자산이 국경 간 자본흐름에 미치는 영향

김효상 한국국제금융학회 2019 국제금융연구 Vol.9 No.2

This study investigates the phenomenon of cross-border crypto-asset premium spillover as potential arbitrage opportunities. Crypto-assets can easily transact anywhere online, so its price should be the same throughout the world. In reality, however, there are some periods that its price differs by countries, known as the Kimchi premium. As cross-border capital flows via crypto-assets are not directly observed, we estimate the spillover effects among Bitcoin premia by currencies to deduce such movements. By adopting the generalized VAR of Diebold and Yilmax (2012) to bitcoin premia in Korea, Japan, Europe, and China, we find strong spillover effect between the bitcoin premia of Korean Won and Japanese Yen. During 2016Q3 and 2017Q1, when bitcoin trading dominated with Chinese Yuan, the premium of the Korean Won received substantial spillover effect from that of the Chinese Yuan. After 2017Q2, when the Chinese government imposed regulations on crypto-asset transactions, the impact of the premium of the Japanese Yen has become more significant to that of Korean Won. Our results suggest that there are cross-border capital flows that follow arbitrage opportunities. 본 연구는 암호화자산의 프리미엄이 재정차익거래 가능성의 형태로 국경을 넘어 파급되는 현상을 살펴본다. 암호화자산은 인터넷 망을 통해 거래되어 국제 자본이동이 용이한 특성을 가지고 있어, 그 가격이 전 세계적으로 동일해야 한다. 그러나 김치 프리미엄과 같이 암호화자산 가격이 국가별로 상이한 시기가 실질적으로 나타나고 있다. 암호화자산을 통한 국경 간 자본이동은 직접 관찰할 수가 없기 때문에, 통화별 비트코인 프리미엄의 유출⋅유입효과를 분석하여 국경 간 자본이동을 유추하였다. Diebold and Yilmaz(2012)의 일반화된 VAR 방법론을 한국, 일본, 유럽, 중국의 비트코인 프리미엄에 적용하여 추정한 결과, 특히 한국과 일본의 비트코인 프리미엄이 상호간 영향을 크게 미친 것으로 나타났다. 한국의 비트코인 프리미엄은 전 세계적으로 비트코인의 위안화 거래가 활발했던 2016년 3기부터 2017년 1분기에는 중국으로부터의 영향이 상대적으로 큰 것으로 나타났으며, 중국 당국의 암호화자산 거래 규제 이후인 2017년 2분기 부터 4분기에는 일본으로부터의 영향이 큰 것으로 추정되었다. 이러한 통화별 비트코인 프리미엄의 상호간 파급효과는 암호화자산을 이용한 재정차익거래 유인에 따른 국경 간 자본이동이 있었음을 시사한다.

만성콩팥병 환자에서 혈당관리 쉽게하는 법

김효상 대한내과학회 2019 대한내과학회 추계학술대회 Vol.2019 No.2

이명으로 인한 불편감과 수면의 질의 상관관계

김효상,임재현,한승훈,이민영,박무균,이준호,오승하,서명환 대한이비인후과학회 2015 대한이비인후과학회지 두경부외과학 Vol.58 No.11

Background and Objectives There exist few studies about relationship between tinnitus and sleep disturbance. Furthermore, the currently available studies have some limitations of confounding factors. This study evaluated correlation between tinnitus and sleep quality, especially by controlling depression and anxiety factors. Subjects and Method The present study was planned as a cross sectional study using questionnaires. Using 46 patients with tinnitus, sleep quality was investigated by Pittsburgh Sleep Quality Index (PSQI) score, anxiety by State-Trait Anxiety Inventory (STAI, axis1 and axis2), depression by Beck Depression Inventory (BDI), and tinnitus induced distress by Tinnitus Handicap Inventory (THI). The final analysis method was multiple regression analysis. THI and PSQI were regarded as dependent and independent variables, respectively. BDI and STAI were regarded as confounding factors. Results Each factor (PSQI, two STAI, and BDI) revealed significant correlation with THI score. Considering four factors together with regression analysis, PSQI score was the most influencing factor on THI score (p=0.002). Conclusion Although depression and anxiety were both influencing factors on tinnitus-induced distress as known previously, sleep quality influenced tinnitus-induced distress came out as the most significant factor in the multivariable analysis.