• 제목/요약/키워드: Reliability Improvement

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품질관리기법을 이용한 도시철도차량 신뢰도 향상방안 연구 (A Study on the Urban Transit Vehicle Reliability Improvement Method using Quality Control Technique)

  • 박기준
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.860-869
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    • 2011
  • It is very important that reduce the maintenance cost and extend life time of the urban transit EMU through effective maintenance method research. The maintenance cost of the urban transit EMU shares 60%~70% of it's life cycle cost. It means that the maintenance cost is bigger than the introduction cost of the urban transit EMU. In this study, I introduces a quality control technique to improve the urban transit vehicle reliability. I suggest the control chart using quality control technique. And the control charts apply to the Static Inverter of EMU.

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V5.2 링크 식별 절차의 신뢰성 향상 방안 (Improvement of Reliability in V5.2 Link Identification Procedure)

  • 이충돈;김영화방효찬최승욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.249-252
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    • 1998
  • ETSI(European Telecommunications Standards Institute) 300 34701, ITU-T(International Telecommunication Union) G.965 recommended PSTN, CONTROL, LINK CONTROL, BCC, PROTECTION protocols on V-Interfaces. But it is possible to occur misalignment between LE(Local Exchange) and AN(Access Network), especially in link identification procedure because there isn't any comment about V5.2 system management. In this paper we propose S/W guard timer to improve reliability in V5.2 link identification procedure in scope of Recommendation.

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각 반응의 목표 영역 존재시의 다반응 최적화: 상대변화 제곱합의 최소화에 의한 방법 (Multiresponse Optimization in the Presence of the Goal Regions for the Respective Responses: A Method by Minimization of the Sum of Squares of Relative Changes)

  • 홍승만;임성수;이민우
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제1권2호
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    • pp.165-173
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    • 2001
  • The desirability function approach by Derringer and Suich (1980) and the generalized distance approach by Khuri and Conlon (1981) are two major approaches to multiresponse optimization for improvement of quality of a product or process. So far, the desirability function method has been the only tool for multiresponse optimization in the situations where there are the goal regions for the respective responses. For such situations, we propose a multiresponse optimization method based on the generalized distance approach.

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P-RAM 기술의 전망

  • 정홍식
    • 한국반도체및디스플레이장비학회:학술대회논문집
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    • 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
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    • pp.21-40
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    • 2006
  • [ ${\Box}$ ] Opportunities for PRAM Nearly ideal memory characteristics Potential for high density & low cost memory ${\Box}$ Technical Challenges Writing current reduction is the most urgent issue. ${\to}$ chalcogenide, programming volume, current density, heat loss control Improvement of writing speed, reliability ${\Box}$ Prospects (PRAM as a Mainstream Memory) Evenn, We have demonstrated 256Mb PRAM Realization of high density and low cost PRAM with good reliability will be key succss factor. We need to develop PRAM specific applications.

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Development of Failure Reporting Analysis and Corrective Action System

  • 홍연웅
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2006년도 추계 학술발표회 논문집
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    • pp.97-112
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    • 2006
  • FRACAS(Failure Reporting, Analysis and Corrective Action System) is intended to provide management visibility and control for reliability and maintainability improvement of hardware and associated software by timely and disciplined utilization of failure and maintenance data to generate and implement effective corrective actions to prevent failure recurrence and to simplify or reduce the maintenance tasks. This process applies to acquisition for the design, development, fabrication, test, and operation or military systems, equipment, and associated computer programs. This paper shows the FRACAS development process and developed FRACAS system for a defense equipment.

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Analysis and Improvement of Reliability in IGZO TFT for Next Generation Display

  • Fujii, Mami;Fuyuki, Takashi;Jung, Ji-Sim;Kwon, Jang-Yeon;Uraoka, Yukiharu
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.326-329
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    • 2009
  • We investigated the degradation of $In_2O_3-Ga_2O_3$-ZnO (IGZO) thin-film transistors (TFTs), which is promising device for driving circuits of nextgeneration displays. We performed the electronic stress test by applying gate and drain voltage. We discussed the degradation mechanism by thermal analysis and device simulation.

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몰딩공정을 응용한 플립칩 언더필 연구 (Studies on Flip Chip Underfill Process by using Molding System)

  • 한세진;정철화;차재원;서화일;김광선
    • 반도체디스플레이기술학회지
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    • 제1권1호
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    • pp.29-33
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    • 2002
  • In the flip-chip process, the problem like electric defect or fatigue crack caused by the difference of CTE, between chip and substrate board had occurred. Underfill of flip chip to overcome this defects is noticed as important work developing in whole reliability of chip by protecting the chip against the external shock. In this paper, we introduce the underfill methods using mold and plunge and improvement of process and reliability, and the advantage which can be taken from embodiment of device.

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전철용 고분자 장간애자 실용화 (Installation of Polymer Stem Insulator for Electric Railway)

  • 김수연;이상진;김영성;김동욱
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1999년도 추계학술대회 논문집
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    • pp.352-359
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    • 1999
  • Polymer stem insulator for an electric railway has been developed in 1995 in Korea. Owing to its excellent electrical and physical characteristics, KT mark was awarded for the developed polymer stem insulator. After new specification of KNR(Korea National Railway) was established, tile evaluation of long-term reliability combined with the improvement of manufacturing process was carried out. In 1998, this polymer stem insulator was installed in commercial electrical railway line. This paper presents the long-term reliability properties of the installed polymer stem insulator compared with conventional insulator. The location of tile installed polymer stem insulator in KNR is also introduced.

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DARS에 의한 CAPSS 배출자료의 불확도 평가 (Uncertainty Assessment for CAPSS Emission Inventory by DARS)

  • 김정;장영기
    • 한국대기환경학회지
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    • 제30권1호
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    • pp.26-36
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    • 2014
  • The uncertainty assessment is important to improve the reliability of emission inventory data. The DARS (Data Attribute Rating System) have recommended as the uncertainty assessment technic of emission inventory by U.S. EPA (Environmental Protection Agency) EIIP (Emission Inventory Improvement Program). The DARS score is based on the perceived quality of the emission factor and activity data. Scores are assigned to four attributes; measurement/method, source specificity, spatial congruity and temporal congruity. The resulting emission factor and activity rate scores are combined to arrive at an overall confidence rating for the inventory. So DARS is believed to be a useful tool and may provide more information about inventories than the usual qualitative grading procedures (e.g. A through E). In this study, the uncertainty assessment for 2009 CAPSS (Clean Air Policy Support System) emission inventory is conducted by DARS. According to the result of this uncertainty assessment, the uncertainty for fugitive dust emission data is higher than other sources, the uncertainty of emission factor for surface coating is the highest value, and the uncertainty of activity data for motor cycle is the highest value. Also it is analysed that the improvement of uncertainty for activity data is as much important as the improvement for emission factor to upgrade the reliability of CAPSS emission inventory.