• 제목/요약/키워드: decreasing case

검색결과 1,217건 처리시간 0.026초

TiO2/UV공정을 이용한 수중 MTBE의 광분해 특성 (Characteristic of Photodegradation of MTBE Using TiO2/UV Process)

  • 류성필;김성수;오윤근
    • 한국환경과학회지
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    • 제13권3호
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    • pp.289-295
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    • 2004
  • The objective of this study is to delineate removal efficiency of the MTBE in solution by $TiO_2$ photocatalytic degradation as a function of the following different experimental conditions: Initial concentration of MTBE, air flow rate in solution, $H_2O_2$ dosage and pH of the solution. Photodegradation rate was increased with decreasing initial concentration of MTBE. The removal efficiency was 82% after 180 min in the case of MTBE concentration of 100 mg/L but 100% after 180 min in the case of 20 mg/L. Removal efficiency was increased with increasing pH, $H_2O_2$ dosage and air flow rate in solution.

인공경량콘크리트의 마모저항성에 관한 연구 (Research on Abrasion Resistance of Artificial Lightweight Concrete)

  • 이창수;유보선;남창식
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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    • pp.205-206
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    • 2010
  • 본 연구는 인공경량콘크리트와 보통콘크리트의 마모저항성에 대한 실험이다. 동일조건에서는 인공경량콘크리트의 마모손실률이 물-결합재비가 커짐에 따라 더욱 증가하지만 플라이애쉬를 혼입한 경우 마모손실률의 차이는 감소하며 물-결합재 30%와 플라이애쉬 15%인 경우 인공경량콘크리트와 보통콘크리트의 마모손실률의 차이는 약 3%정도로 거의 발생하지 않았다.

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GPS RAIM에서의 2개 파라미터 고장진단에 대한 연구 (Study on Two-Failure GPS RAIM Problem)

  • 유창선;이상정
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.194-194
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    • 2000
  • In aviation navigation by GPS, requirements on availability and integrity must be absolutely satisfied for safety. Current study on accomplishing this integrity includes RAM(Receiver Autonomous Integrity Monitoring), checking integrity internally in GPS receiver itself. However RAIM techniques have be investigated and presented under assumption that there is included only one fault in measurements from GPS, In case of multiple fault, an interaction among bias errors sometimes results in decreasing the effect of multiple fault. This may make an exact fault detection and identification difficult, and study on mutiple fault RAIM focused on. This paper explains the reasons that techniques applied on single fault are not adequate to extend directly to two faults case and shows that RAIM solution on two fault may be given in revised parity space.

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대혈관 전위증 1예 보고 (Complete Transposition of the Great Arteries with Atrial Septal Defect -One Case Report-)

  • 조건현
    • Journal of Chest Surgery
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    • 제12권3호
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    • pp.197-206
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    • 1979
  • The most common abnormal relationship between the great arteries and ventricle is transposition of great arteries, among which complete D-transposition is a common and lethal malformation. Without appropriate treatment, the infant born with transposition of the great arteries rarely survives the first year of life. In contrast to the grim hopelessness of only a few years ago, modern aggressive palliative and corrective surgical interventions can provide such infants with considerable hope for adolescent and adult life. Up until this time, intraatrial baffle technique for re-direction of venous return, which was proposed by Mustard originally, has been successfully applied to infants and children in many foreign clinics with decreasing trend of the operative risk. In this report, we present one case of a 4 year-old girl having complete D-transposition of the great arteries with atrial septal defect, and reviewed the relevant literatures.

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다이아몬드 공구의 절삭거리에 따른 정밀가공 특성 연구 (A Study on the Precision Cutting Characteristics by the Diamond Tool on the Cutting Distance)

  • 유기현;정진용
    • 한국생산제조학회지
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    • 제7권5호
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    • pp.127-133
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    • 1998
  • This research intends to gain the sight for the qualitative characteristics of precision cutting by using the CNC lathe with a mono-crystal diamond(MCD) and a poly-crystal diamond(PCD) tool on the cutting distance. In case of an MCD tool, as the cutting distance increases, the surface roughness becomes worse and the standard deviation of surface roughness is small. In case of a PCD tool, as the cutting distance increases, the surface roughness becomes stable with a large standard deviation. The cutting force ratio(Ft/Fn) decreases as the nose radius increases and the decreasing ratio becomes larger for small nose radius.

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GLOBALIZATION OF A LOCAL MARKET DYNAMICS ONTO AN INFINITE CHAIN OF LOCAL MARKETS

  • Kim, Yong-In
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제16권1호
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    • pp.133-145
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    • 2009
  • The purpose of this paper is to extend and globalize the Walrasian evolutionary cobweb model in an independent single local market of Brock and Hommes ([3]), to the case of the global market evolution over an infinite chain of many local markets interacting each other through a diffusion of prices between them. In the case of decreasing demands and increasing supplies with a weighted average of rational and naive predictors, we investigate, via the methods of Lattice Dynamical System, the spatial-temporal behaviors of global market dynamics and show that some kind of bounded dynamics of global market do exist and can be controlled by using the parameters in the model.

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Cradle(R)의 Web Access를 이용한 철도시스템 사양관리환경 구축방안 연구 (A Study on the Method to Establish an User Environment of a Requirements Management Database Using Web Access of Cradle(R))

  • 정경렬;박철호;송선호;허지열
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.132-140
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    • 2009
  • The Cradle(R) is specialized systems engineering tool that developed by 3SL(Structure Software System Limited) that has headquarters in U.K. and U.S.A.. It is recognized as the fastest growing Computer-Aided Systems Engineering Tool(CASE Tool). We built up requirements management database by using Cradle(R) on urban maglev program in Korea. So Cradle(R) provide a network function, is available accesses of clients in external organization that is associated on urban maglev program by the internet. However the network function of Cradle(R) require an opening of some a specific network ports and may causes a decreasing network speed. In this paper, we propose the method to establish an user environment of a requirements management database that overcome constraints on network condition.

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퇴행성(退行性) 관절염(關節炎)을 동반(同伴)한 비만인(肥滿人)의 한방비만치료(韓方肥滿治療) (Herbal Diet of Obese with Osteoarthristis)

  • 박병준
    • 한방비만학회지
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    • 제4권1호
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    • pp.201-211
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    • 2004
  • The treatment of obesity is increasingly becoming important to effective medical treatment, especially in case involving a degradation of the lower joints. A recent case placed two osteoarthritic obese patients who underwent arthroscopic surgery in a regiment of herbal diet. Alter 3-5 months of receiving this oriental treatment, the patients not only lost weight, but also showed significant reduction of joint inflammation and pain. It is true that obese patients with lower limb or osteoarthritis who have undergone normal obesity treatment regularly for 5 years or more will find the treatment becomes less effective over times. However, for patients suffering from lower limb pain or osteoarthristis, oriental obesity treatment, on the whole was effective in decreasing five key areas(5D). For this reason, it is necessary for oriental medicine to be given further study and consideration as an effective treatment of obesity.

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디젤엔진 피스톤 링 코팅 층의 마찰특성 (Frictional characteristics of coating layer in diesel engine piston ring)

  • 장정환;주병돈;이호진;김은화;문영훈
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.294-297
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    • 2009
  • The frictional behaviors of Cermets/Cr-Ceramics and Cu-Al coatings of piston ring were investigated. Friction tests were carried out by pin-on-disk test and materials properties of coating layer were analyzed by nano indentation tester. Higher friction coefficient was obtained at harder coating with rougher surface. In case of hard-coating, the scratch depth, width and pile-up height had close relationship with indentation hardness. So the scratch width, depth and pile-up height increases with decreasing friction coefficient. But in case of soft-coating, the friction coefficients are strongly dependent on the morphological characteristics after nano scratching more than indentation hardness.

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극초고압 디젤분무의 충돌면 온도거동에 관한 연구 (A Study on the Temperature Behavior on Impinging Plate of Diesel Spray with Ultra High Pressure)

  • 이종태;정대용
    • 대한기계학회논문집B
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    • 제29권3호
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    • pp.402-408
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    • 2005
  • The instantaneous temperature behaviors on impinging plate in case of ultra high pressure have been measured and analyzed by using the instantaneous temperature probe and ultra high pressure injection equipment. The temperature drop was largest at P1 which is center of impinging spray and decreased with propagation of spray to the radius direction. The temperature drop was bigger in case of higher temperature of impinging plate. The temperature drop decreased with increase of injection pressure. But decreasing rate of temperature drop was slight over 2,500 bars. Therefore, it was predicted that the fuel evaporation versus the increase of injection pressure was maximum at around 2,500 bars.