• 제목/요약/키워드: DEC

검색결과 1,482건 처리시간 0.028초

리튬이온 2차 전지용 전해액의 이온전도도와 전기화학적 특성 (Conductivity and Electrochemical characterization of Lithium ion secondary battery electrolytes)

  • 임동규;이제혁;변문기;조봉희;김영호;우병원;나두찬
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
    • /
    • pp.295-298
    • /
    • 1998
  • We have investigated ionic conductivity and electrochemical stability of the electrolytes containing organic solvent. Ion conductivities were measured between 10 and 80$^{\circ}C$, and electrochemical stabilities were determined by cyclic voltammetry on glassy carbon, platinum and aluminum electrodes. Ionic conductivity of electrolyte(EC:DEC=1:1) with IM LiPF$\_$6/ shows better than that of the other electrolytes having Li salts. The IM LiBF$_4$-PC electrolyte exhibits good electrochemical stability. IM LiPF$\_$6/ (EC:DEC=1:1) and IM LiPF$\_$6/ (EC:DMC=1:1) electrolytes are used for the high capacity of battery system.

  • PDF

종방향 활동체결구를 사용한 당산철교 장대레일화 사례 (CWR for Seoul Subway No 2 DangSan Bridge by ZLR (Zero Longitudinal Restraint))

  • 이덕영;공선용;권순섭;김은
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2003년도 추계학술대회 논문집(II)
    • /
    • pp.379-384
    • /
    • 2003
  • DangSan Bridge of Seoul Subway No 2 was rebuilt by safety reason. From Dec 1996 to Dec 1999 we were in charge of permanent way design of this rebuilt project. Especially we applied maintenance free system on the bridge by Cologne Egg alternative (ALT1) base plate and CWR (Continuous Welded Rail) by ZLR(Zero Longitudinal Restraint) for 125m (south approach section), 120m long(north approach section). This thesis generally introduce for CWR by ZLR which was first adapted CWR system in Korea.

  • PDF

금속(Al, Cr, Ni)의 일함수를 고려한 쇼트키 장벽 트랜지스터의 전기-광학적 특성 (Metal work function dependent photoresponse of schottky barrier metal-oxide-field effect transistors(SB MOSFETs))

  • 정지철;구상모
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
    • /
    • pp.355-355
    • /
    • 2010
  • We studied the dependence of the performance of schottky barrier metal-oxide-field effect transistors(SB MOSFETs) on the work function of source/drain metals. A strong impact of the various work functions and the light wavelengths on the transistor characteristics is found and explained using experimental data. We used an insulator of a high thickness (100nm) and back gate issues in SOI substrate, subthreshold swing was measured to 300~400[mV/dec] comparing with a ideal subthreshold swing of 60[mV/dec]. Excellent characteristics of Al/Si was demonstrated higher on/off current ratios of ${\sim}10^7$ than others. In addition, extensive photoresponse analysis has been performed using halogen and deuterium light sources(200<$\lambda$<2000nm).

  • PDF

도시철도차량 운영 및 발주관련 프로그램의 RIMS 적용 (A Study on Application of RIMS for City Rail-road Management and Ordering Programs.)

  • 전서탁;김현철;이도선
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2008년도 춘계학술대회 논문집
    • /
    • pp.1301-1307
    • /
    • 2008
  • The Seoul-Metro is the first city railroad corporation to operate RIMS(Rolling-stock Information Maintenance System). The development of "RIMS Project" and trial running task were started from Mar 29, 2001. Finally, this project was completed successfully on Dec 31, 2005, as integrated systems including light or heavy maintenance works in Ji-Chuk and Chang-Dong Rolling-stock Offices. After that, from 2006 to Dec 31, 2007, we promoted a this new program to other four rolling-stock offices (Su-Seo, Gun-Ja, Sin-Jeong) and the headquarter. For the duration of trial running, we developed and applied new complementary program having made up for the weak points or defects. The series of new program which were newly developed and applied are comprised of an operation management, trouble management, wheel management, heavy maintenance table automatic creation programs and ordering prediction programs to purchase goods smoothly. The Seoul-Metro have registered these programs(RIMS) to Computer Program Protection Committee. We'd like to introduce a composition of program for enhancement of a city railroad Information Systems.

  • PDF

Three-Dimensional Modelling and Sensitivity Analysis for the Stability Assessment of Deep Underground Repository

  • Kwon, S.;Park, J.H.;Park, J.W.;Kang, C.H.
    • Nuclear Engineering and Technology
    • /
    • 제33권6호
    • /
    • pp.605-618
    • /
    • 2001
  • For the mechanical stability assessment of a deep underground high-level waste repository. computer simulations using FLAC3D were carried out and important parameters including stress ratio, depth, tunnel size, joint spacing, and joint properties were chosen from sensitivity analysis. The main effect as well as the interaction effect between the important parameters could be investigated effectively using fractional factorial design . In order to analyze the stability of the disposal tunnel and deposition hole in a discontinuous rock mass, different modelings were performed under different conditions using 3DEC and the influence of joint distribution and properties, rock properties and stress ratio could be determined. From the three dimensional modelings, it was concluded that the conceptual repository design was mechanically stable even in a discontinuous rock mass.

  • PDF

건널목 개선사업 효과의 계략적 평가 방법의 적용 (Localization Effort of Rail Grade Crossing Impact Analysis with GradeDec2000)

  • 조성훈;서선덕;권경숙
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2001년도 춘계학술대회 논문집
    • /
    • pp.88-96
    • /
    • 2001
  • Rail crossings are major accident-prone areas. Higher traffic volume, frequent rail operation, increased train speed all contribute to increased accident rate and severity In Korea efforts are being made to upgrade currently at-grade rail crossings to grade crossings. There is, however, no quantified analysis measures to analyse the impact of rail grade crossing, thus make it difficult to prioritize different projects under the budget constraints. Projects are selected based on the negotiation between Korea National Railway(KNR) and local governments. To shed light on the development effort for Korean procedure, GradeDec 2000 program of Federal Railroad Adminstration(FRA) was applied for Korean context. Case study involving three rail crossing was ca]lied out, and results are analyzed. Research efforts which need further attention are identified, research direction is analyzed considering local procedure, and issues in the application of the procedures are discussed in detail.

  • PDF

지류의 수질이 금호강 본류의 수질에 미치는 영향에 관한 연구 (The Effect of Branches on Kumho River's Water Quality)

  • 양득석;배헌균
    • 한국환경과학회지
    • /
    • 제21권10호
    • /
    • pp.1245-1253
    • /
    • 2012
  • In this study, how branches of Kumho River affect to the water quality on Kumho River was investigated. Water samples from six sampling points at Kumho River and three at each branch were taken from Dec. 2009 to Dec. 2011. As results, Namcheon affected BOD and T-P concentrations on Kumho River while Sincheon did only T-P concentrations. However, the water quality of Kumho River was improved because of Sincheon in terms of BOD and COD concentrations. This was the results from management of Sincheon wastewater treatment facility and Jisan wastewater treatment facility which might be the best example for managing wastewater treatment facilities. Dalsecheon would not affect the water quality of Kumho River although it had bad conditions of water quality because of lack of its water quantity comparing to Kumho River's.

MARYLAND BRIDGE의 적용분포 및 결합실패에 관한 임상적 연구(I) (A CLINICAL STUDY ON THE DISTRIBUTION AND THE BOND FAILURE OF ETCHED (MARYLAND) BRIDGE: A PRELIMINARY REPORT OF 135 CASES)

  • 양재호
    • 대한치과보철학회지
    • /
    • 제24권1호
    • /
    • pp.7-16
    • /
    • 1986
  • The purpose of this study was to examine the distribution and the bond failure of the acid-etched ceramometal retainer (Maryland Bridge). 126 subjects who treated by faculty and residents of Department of Prosthodontics, Seoul National University Hospital from Dec. 1982 to Dec. 1986 were selected for this study. From the foregoing study author obtained the following conclusions. 1. A total of 135 restorations were placed in the mouths of patients ranging in age from 11 to 10 years (man 62, woman 64). 2. Most restorations were applied to replace anterior teeth. 3. It was found that of the total number of bridges constructed 59.3 percent were the three-unit type. 4. Replacing one tooth mining was the most frequent cases (74.1 percent). 5. Of the total number of cases, 10.4 percent stowed bond failure. 6. The bond failure, author suggest, be due to one or more of mis-fit of framework, occlusion, material in itself, faulty case selection and lack of technique.

  • PDF

Sub-50nm Double Gate MOSFET의 특성 분석 (Characteristics analysis of Sub-50nm Double Gate MOSFET)

  • 김근호;고석웅;이종인;정학기
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국해양정보통신학회 2002년도 추계종합학술대회
    • /
    • pp.486-489
    • /
    • 2002
  • 본 논문에서는 50nm 이하의 double gate MOSFET의 특성을 조사하였다. 1.5V의 main gate 전압과 3V의 side gate 전압이 인가될 때 I-V 특성으로부터 IDsat=510$\mu$A/$\mu\textrm{m}$을 얻을 수 있었다. 이때, 전달 컨덕턴스는 111$\mu$A/V, subthreshold slope는 86mV/dec, DIBL값은 51.3mV이다. 그밖에 TCAD tool이 소자 시뮬레이터로서 적합함을 나타내었다.

  • PDF

Forecasting of Stream Qualities in Gumho River by Exponential Smoothing at Gumho2 Measurement Point using Monthly Time Series Data

  • Song, Phil-Jun;Lee, Bo-Ra;Kim, Jin-Yong;Kim, Jong-Tae
    • Journal of the Korean Data and Information Science Society
    • /
    • 제18권3호
    • /
    • pp.609-617
    • /
    • 2007
  • The goal of this study is to forecast the trend of stream quality and to suggest some policy alternatives in Gumbo river. It used the five different monthly time series data such as BOD, COD, T-N and EC of the nine of Gumbo River measurement points from Jan. 1998 to Dec. 2006. Water pollution is serious at Gumbo2 and Palgeo stream measurement points. BOD, COD, T-N and EC data are analyzed with the exponential smoothing model and the trend is forecasted until Dec. 2009.

  • PDF