• Journal of Positioning, Navigation, and Timing
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• 제11권3호
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• pp.191-198
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• 2022

In order to increase the practical use and navigational application performance of the Korean Positioning System (KPS), it is required to provide interoperability with other Global Navigation Satellite System (GNSS). This kind of interoperability can be obtained by broadcasting the time offset between KPS and GNSS using a KPS navigation message. With the assumption that KPS Time (KPST) will be generated by the similar method and equipment of UTC(KRIS), the overall behavior of KPST will be close to that of UTC(KRIS). Therefore, the time offset between KPST and GPS Time (GPST) is estimated by using UTC(KRIS) instead of KPST because KPST can not available at the present time. In this paper, we describe the estimation results of the KPS to GPS Time Offset (KGTO) obtained by using a GNSS time transfer receiver which reference inputs are fed from UTC(KRIS). The estimated KGTO performance is compared to the time offset between UTC(KRIS) and UTC(USNO) which is used to generate GPST and considered as the real GPST. The time offset between UTC(KRIS) and UTC(USNO) is obtained by using the Bureau International des Poids et Mesures (BIPM) Circular T report. From the results, it is observed that KGTO can be estimated under 10 ns with the assumption that KPST will be generated by a similar method of UTC(KRIS) generation.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2002년도 동계연구발표회 논문개요집
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• pp.232-233
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• 2002

Nanostructed high energy Nd-Fe-B based bulk magnet can be prepared by hot-working process (hot press and die-upset) from melt-spun amorphous or nanocrystalline powder.[1] Recently, we have investigated a modified method, current-applied pressure-assisted (CAPA) process, to produce nanocrystalline isotropic and anisotropic NdFeB magnets. The process consists of current-applied pressing the melt-spun powders to obtain isotropic precursor subsequent current-applied deforming the precursor to obtain textured magnet.[2-3] (omitted)

• 대한조선학회지
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• 제17권3호
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• pp.29-35
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• 1980

With installation of the computerized data acquisition system on the towing carriage of KRIS towing tank, the testing techniques of resistance test, propeller open-water test, self-propulsion test and wake survey at propeller disk were remarkably improved and automated. For the self-propulsion test a new method was developed with aid of a digital desk-top computer. This method is based on extracting advantages both from British method and Continental method, that is, the accuracy from the constant speed method and the effciency from the constant load method. The KRIS method has been successfully practized with the improved accuracy, stability and efficiency. Details of the new method are described in this paper.

• 대한안전경영과학회지
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• 제22권4호
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• pp.1-8
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• 2020

In general, companies operate systematically in response to financial risks such as exchange rates and liquidity, while they are vulnerable to risks in the manufacturing and sales processes. In particular, logistics refers to the activities for planning, managing and implementing efficient flows from the starting point of goods and products to the point of consumption, The purpose of this study was to develop key risks and key risk management indicators (KRIs) for risks that undermine logistics efficiency so that logistics risks can be effectively prevented and managed. As a result, 40 risk management indicators (KRIs) were developed in a total of six categories in the logistics sector, and the definition, calculation method and early warning grade of each KRI were presented so that companies could prevent risks in advance in logistics activities and contribute to enhancing efficiency of their work.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.490-492
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• 2006

본 논문에서는 현재 KRISS(한국표준과학연구원)에 구축 된 JCSAT-1B 위성과 PAS-8 위성 그리고 PAS-4 위성을 이용하여 KRISS와 NICT(일본의 정보통신연구기관)간의 양방향 시각비교를 통하여 그들의 안정도를 비교분석하고 향후 JCSAT-1B 위성의 백업시스템으로써 PAS-4 위성과 PAS-8 위성의 활용성을 검토하였다.

• 한국조명전기설비학회지:조명전기설비
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• 제11권4호
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• pp.21-31
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• 1997

• 월간경쟁저널
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• 제161호
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• pp.56-67
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• 2012

• 한국진공학회:학술대회논문집
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• 한국진공학회 2002년도 제23회 학술발표회 초록집
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• pp.135-135
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• 2002

• 한국항해항만학회지
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• 제40권1호
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• pp.15-20
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• 2016

본 연구에서는 내륙에서 수신한 로란 9930M 포항 송신국의 로란신호를 이용하여 Loran differential ASF를 측정하였고, 이를 통해 로란 신호의 시각동기 정확도를 향상시켰다. Differential ASF는 한국표준과학연구원(KRISS)의 UTC(KRIS) 기준 TOA 데이터에서 충남대학교와 국립해양측위정보원에 설치된 원자시계를 기준으로 동시에 측정된 TOA 데이터를 각각 차분함으로써 구하였다. 자기장 안테나를 이용한 충남대학교에서의 60분 평균 TOA 측정결과는 $0.1{\mu}s$ 이내의 변동성을 보였고 국립해양측위정보원에서의 TOA 측정결과는 $0.05{\mu}s$ 이내의 변동성을 보였다. 또한 충남대학교와 국립해양측위정보원에서의 60분 평균 differential ASF 측정결과는 수신국의 주변 환경 영향에 의해 최대 $0.1{\mu}s$ 정도까지 시각 변동성을 나타냈다. 따라서 UTC(KRIS)를 기준으로 측정한 TOA 데이터로 충남대학교와 국립해양측위정보원 측정 데이터를 각각 보상하면 differential ASF 변화가 상쇄되어 로란 신호를 이용한 시각동기 정확도를 10 ns 정도 이내로 향상시킬 수 있다. 그리고 세슘원자시계를 기준으로 포항 송신국 로란 신호의 기준위상과 KRISS에서의 로란 수신기의 출력 기준위상을 측정하여 두 지점 사이의 ASF는 약 $3.5{\mu}s$로 나타났다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.103-103
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• 2011

고진공의 바이러스격인 탈기체의 속성과 KRISS에서 보유중인 탈기체의 측정장치들의 각 특징들을 소개한다. 또한 산업체에서 시험 의뢰한 재료 종류 분석을 통해 산업체의 동향을 간접적으로 제시한다.