• Journal of Mechanical Science and Technology
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• 제16권9호
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• pp.1033-1039
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• 2002

Partial penetration welding joint refers to the groove weld that applies to the one side welding which does not use steel backing and to both side welding without back gouging, that is, the partial penetration welding joint leaves an unwelded portion at the root of the welding area. In this study, we analyzed the residual stress and fracture on the thick metal plates that introduced the partial penetration welding method. According to the above-mentioned welding method, we could draw a conclusion that longitudinal stress and traverse stress occurred around the welding area are so minimal and do not affect any influence. We also performed the fracture behavior evaluation on the partial penetration multi pass welding with 25.4 mm thick plate by using the J-integral, which finally led us the conclusion that the partial penetration multi-pass welding method is more applicable and effective in handling the root face with less than 6.35 mm.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.566-569
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• 2004

The recent growth in the use of impactive and nonlinear loads, electronic devices sensitive to power quality has caused many power quality problems. Recently, in power system, not only the reliability of the power supply but also the DVR(Dynamic Voltage Restorer) are being studied more and more. The DVR is a series compensator which can instantaneously compensate a voltage variation in supply side, and is a more effective than a existing UPS(Uninterruptible Power Supply) which can be only used in limited range of loads such as single load. Hence, in this paper, a study of inverter side L-C filter output Voltage for DVR is discussed.

• 대한방사선기술학회지:방사선기술과학
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• 제12권1호
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• pp.17-23
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• 1989

We have developed of the exposure technique for the chest radiography to get different contrast in left and right lung fields simultaneously for the effective diagnosis, I.E., get high contrast to detect tuberculosis, dispersal shadow or exudative lesions of early tuberculosis and get better sharpness and wider latitude to detect growing lesions of lung cancer or lesions overlapped with bones. As a result, by using an additional filter Cu 1.2mm with BX-III screen side and sheet of yellow cellophane on BF-III screen side at the conventional KV ($80KV{\sim}100KV$) for the chest X-ray, we can get similar densities in both left and right lung fields and, thus, this method is considered to be very effective for the quality diagnosis for the routine chest radiography.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 2010년도 춘계국제학술대회
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• pp.65-74
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• 2010

Most university has provided the information system that fit with their university peculiarity only, but there is not proper evaluation on the user satisfaction by that. In this study, first of all, it analysed which factors give satisfaction to the users when university operated the information systems and inquired the needed outcome variables in order to operate successful university information system. Through the inquisition of fitting supposition, we got something that organizational support and computer self efficacy which is personal factors were effected as an affirmative side to make a user satisfactions of information system. In more detail, organizational support and personal factors effected as an affirmative side to the quality of information system. And, so the quality of information system was influenced to user satisfaction that it raised the work result and increased the work products in organization through personal outcomes.

• 조명전기설비학회논문지
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• 제24권9호
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• pp.108-117
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• 2010

The main contents of this paper are the PQM system construction case and distribution system harmonic voltage analysis. The PQM system has constructed by KEPCO in order to investigate power quality of distribution power system for new power quality standard of KEPCO. In result, we have confirmed that voltage harmonic measurement value of the high voltage contract customer 8 households is suitable the KEPCO harmonic standard tentative plan. And the voltage harmonic value of distribution line end side is not always more high than source side by harmonic current offset effect. In the future, acquired data by season, region, load from the PQMS will be used on the resonable harmonic standard enactment in KEPCO.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권8호
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• pp.387-394
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• 2005

This paper deals with the grid-interactive small battery energy storage system, which aims at the integration o( power quality improvement and demand side management. The main purpose of the proposed system is to achieve the peak power cutting and to compensate the current harmonics and reactive power at the point of installation on power distribution for residential homes. paper deals with the grid-interactive small battery energy storage system, In this paper, the basic principle and control algorithm is analyzed, theoretically and the design methodology of the system is discussed. To verify the proposed system, a comprehensive evaluation with theoretical analysis, simulation and experimental results for 1 KVA load capacity is presented.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.1062-1066
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• 2004

In this study, refrigerant noise at connection of capillary tube and evaporator is investigated. Mechanism of refrigerant noise generation is examined in side-by-side type home refrigerator with two evaporators. It is found that the refrigerant noise is generated during refrigeration room fan-off (R-fan of) for that type refrigerator. The reason is that mass flow rate gets down during R-fan of and flow pattern is changed at outlet of capillary tube. We suggest designs for reduction of refrigerant noise with horizontal double expansion device, muffler, and accumulator. To evaluate those improved designs, sound quality index is used.

• Current Research on Agriculture and Life Sciences
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• 제15권
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• pp.33-38
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• 1997

산지(영천군 청통면 신원리), 평지(영천군 신령면 연정리) 강변지(영천군 금호읍 냉천동)의 과수원에서 각각 '후지'과실을 채취하여 대구시 인근의 과실품질을 조사하였다. 결과는 다음과 같다. 1 각 지역 공히 품질이 평균적인 과실을 채취하였고 강변지 과실 중량이 40g정도 작았고, 과실종경 최소치가 다른 지역에 비해 작았다. 평지 과실의 횡경은 최대치, 최소치 모두 산간지보다 큰 것으로 나타났다. 과형지수는 강변지 과실이 다른 지역에 비해 편원형이었다. 이러한 과형의 차이는 온도, 토양수분함량 등에 의한 것으로 생각된다. 과실 착즙률은 각 지역간 유의한 차가 인정되지 않았다. 2. 각 지역 공히 후지과실 전당의 50%정도가 프락토즈인 것으로 나타났고, 산지의 슈크로즈, 프락토즈, 솔비톨 함량이 다른지역에 비해 높은 수치를 나타내었으나 글루코즈는 다른 지역에 비해 낮은 수치를 나타내었고, 당도는 전당함량과 거의 같은 수치를 나타내었다. 3. 각 지역 공히 후지과실 전산의 98% 정도가 능금산이었고 시트르산이 2%를 차지하였다. 산지과실의 능금산 함량이 다른지역에 비해 높은 수치를 나타내었고 적정산은 전산함량과 거의 같은 수치를 나타내었다.

• 지구물리와물리탐사
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• 제12권2호
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• pp.192-198
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• 2009

사이드스캔소나(Side Scan Sonar)와 SBP (Sub-bottom Profiler)는 최근 해양탐사 기술의 발전과 더불어 수중과 해저면, 그리고 해저면 하부에 대한 정보가 필요한 분야에 많이 활용되어지고 있다. 본 연구에서는 사각형 인공어초가 해저면에 분포하는 지역을 대상으로 사이드스캔소나와 SBP를 이용하여 자료를 취득하였다. 취득된 사이드스캔소나 자료에 대하여 디지털 영상처리 기법인 공간영역과 주파수영역에서의 각종 필터링을 적용하여 필터링의 종류와 매개변수에 따른 특징 및 영상분석을 시도하였다. SBP 자료는 이득회수, 디콘볼루션, 스펙트럼 분석, 뮤팅, 구조보정 등의 탄성파 자료처리과정을 거친 후 단면도를 구하였으며, 또한 통계적 특징에 기인한 평균값과 중앙값을 이용한 영상처리 과정을 거쳐 지층의 연속성 향상을 도모하였다. 사이드스캔소나와 SBP 두 가지 자료를 함께 시각화하는 방법을 이용하여 인공어초의 상태 및 구조물의 침하여부를 보다 쉽게 파악할 수 있었다. 또한 샘플링된 해저퇴적물 시료분석 결과와 사이드스캔소나의 Texture Filtering 적용결과, 그리고 천부지층결과의 연계해석을 통해 지층 상부퇴적물의 종류와 분포 및 두께를 파악할 수 있었다.

• 대한안전경영과학회지
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• 제11권4호
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• pp.229-235
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• 2009

Since 1995, the small and medium enterprise introduced the Quality Innovation Program that is called 100PPM Quality Renovation Program. A point of 2000, the program's name was changed by Single PPM Quality Innovation Program in pursuit of defects below 10ppm in outgoing quality. Nowaday 1,651 companies is received Single PPM Quality Certification from government at the end of 2008. On the other side, the return or withdrawal of certification is going on because of various reasons. In this study, we analyse the status of certification's preservation and cancellation, and suggest the cooperation ideas between government and companies.