• 정보과학회 논문지
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• 제43권8호
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• pp.835-840
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• 2016

몬테카를로 렌더링은 사진과 흡사한 이미지를 렌더링하는 데 널리 쓰이는 기술이다. 그러나 이 기술로 고품질의 이미지를 얻으려면 픽셀 당 샘플의 수를 증가시켜야 하며, 필연적으로 긴 렌더링 시간을 필요로 한다. 이 문제를 풀기 위하여, 이미지 필터링 기술을 적용할 수 있다. 이는 적은 샘플 수로, 노이즈가 존재하는 렌더링 결과를 빠른 시간 내에 구한 뒤, 필터링을 적용하여 추가적인 샘플 없이 정답 이미지에 근사하는 부드러운 이미지를 얻는 방법이다. 본 논문에서는 에이트러스 웨이블릿필터에 스테인의 공평 에러 추정법(SURE)을 적용하여, 실시간에 가까운 속도로 렌더링한 이미지의 노이즈를 제거하는 방법을 제안한다. 슈어(SURE)를 이용하여 에이트러스 웨이블릿 필터의 필터링으로 인한 에러를 추정할 수 있고, 이를 통하여 에러를 줄이는 방향으로 웨이블릿의 계수를 정할 수 있다. 본 연구진은 이 필터링 방법을 최신 실시간 광선추적법 시스템인 엠브리(embree)에 적용하여 성능을 확인하였다.

• 한국콘텐츠학회논문지
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• 제11권1호
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• pp.329-339
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• 2011

본 연구는 비영어권 OECD 21개 국가들을 대상으로 영어능력과 경제활동(국가별 무역량, R&D투자 등), 그리고 경제 성장률과의 관계 분석을 통하여 영어능력이 국가의 경제성장에 미치는 영향을 실증적으로 규명하고자 하였다. 단순회귀분석(OLS)과 표면상무관회귀분석(Seemingly Unrelated Regression Estimation: SURE)의 기법을 사용하여 추정한 결과 체코, 핀란드, 그리고 폴란드를 제외한 여타 국가들에서는 영어능력이 직접적으로 경제성장에 정(+)의 효과를 미친다는 통계학적 유의성이 발견되지 않았다. 그러나 영어 능력은 무역량 증진의 기여를 통하여 간접적으로 경제성장에 영향을 끼치는 것으로 나타났다. 따라서 영어 능력은 경제성장에 있어서 하나의 필요조건이지 충분조건은 아닌 것으로 결론 지울 수 있다. 더불어 영어 능력은 최소한의 물적 자본과, 기술축적, 정치적 안정, 그리고 훌륭한 통치를 보완하는 충분한 보완재 역할을 담당한다면 경제성장에 긍정적인 영향을 끼칠 것이 예상된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.6-7
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• 2018

In the previous study, durometer, namely rubber hardness tester Was used to confirm the possibility of using the setting time of concrete for determination. in this study, the possibility of using condensation time judgment condensation estimation system by comparing the measuring station setting estimation system Measuring needle of the proctor penetration resistance tester by newly making a measurement needle and refining the coagulation estimation system Want to make sure. As a result of this study, it was possible to use one condensation estimation system showing similar correlation between the two types of durometer showing high correlation with the penetration resistance value of proctor testers, It is considered to be fruitful to use the dew condensation estimation system for determining the setting time.

• 상하수도학회지
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• 제23권2호
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• pp.241-249
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• 2009

It is well known that the trend of water demand in large-size water supply systems has been suddenly changed, and many expansions of water supply facilities become unnecessary. To be cost-effective, thus, politicians as well as many professionals lay stress on the adaptive management of water supply facilities. Failure in adapting to the new trend of demand is sure to be the most critical reason of unnecessary expansions. Hence, we try to develop the model and modeling procedure that do not depend on the old data of demand, and provide engineers with the fast learning process. To forecast water demand of Seoul, the Bayesian parameter estimation was applied, which is a representative method for statistical pattern recognition. It results that we can get a useful time-series model after observing water demand during 6 years, although trend of water demand were suddenly changed.

• 한국콘텐츠학회논문지
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• 제10권3호
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• pp.315-325
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• 2010

최근 지식기반경제로의 진입과 함께 인적자본형성으로서의 교육에 관한 문제는 모든 국가들에 있어서 중요한 관심의 대상이 되고 있다. 본 연구는 1970년-2008년 기간 동안 비영어권 OECD 10개 국가들을 대상으로 교육투자와 경제성장과의 관계를 단순회귀분석(OLS) 및 표면상무관회귀분석(Seemingly Unrelated Regression Estimation: SURE) 기법을 사용하여 추정하여 상호 비교분석 하였다. 분석 결과 인적자본의 형성과 관련된 변수들의 추정에서는 교육투자를 비롯하여 R&D투자 및 출산율 모두 통계적 유의성이 높게 나왔으며 또한 경제성장에 정(+)의 영향을 주는 것으로 나타났다. 이들 중 경제성장에 가장 큰 영향을 주는 요소로는 출산율이었으며 다음으로 R&D 투자, 교육투자 순으로 나타났다. 특히 출산율계수의 크기는 R&D 투자의 1.8배, 교육투자의 약 3.5배의 크기로 나타나고 있어 각 국가들의 지속적인 경제성장을 위해서는 R&D투자 및 교육투자뿐만 아니라 출산율 촉진정책도 동시에 고려되어져야 할 것으로 보인다.

• 대한전기학회논문지:전력기술부문A
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• 제51권1호
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• pp.29-36
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• 2002

It is required that the current state of system should be Precisely monitored for efficient and safe operation of the subway power system and it is an important Problem to secure the high quality data for state estimation. The current state of subway power system is estimated by using data transmitted to control center from every measuring instrument. The high accuracy and trust can be maintained if the measured data have a high quality. But it is difficult to estimate the accurate state of system because of the noises in transmitted data and the inaccuracy of measuring instruments. So the object is to reduce the difference between the real values and the measured values in order to improve considerably the inaccuracy due to Instrumental errors and transmission noises using the state estimation method. In this paper, we proposes a new state estimation to estimate the accurate state of the subway power system from the measured values of a Sang-In station in Daegu subway and consider the possibility of application to the real subway power system. on the basis of that. The simulation results show to make sure of the possibility to apply to the real system usefully.

• 아태비즈니스연구
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• 제2권1호
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• pp.23-48
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• 2011

Generally, higher brand equity ends up with higher market share and higher profitability. However, superior brand equity does not guarantee the success in the market. That is, consumer choice is closely related to brand equity but we need more than brand equity to explain this complex phenomenon. We adopt the customer equity concepts: value equity, brand equity, and retention equity. By incorporating value equity and retention equity into customer equity, it is possible to avoid the problems of using the brand equity only. In the paper, we apply this customer equity concepts to cellular phone and investigate the effects of antecedent variables such as exposure, knowledge, positive experience and negative experience on the components of customer equity. In addition, as surrogate measure of customer lifetime value, the weighted measure of purchase intention, consideration set inclusion, and next purchase is used as dependent variable. We estimate the effects of components of customer equity at the brand level and aggregate level using SURE model. Estimation results show that Apple has currently low market share but has high future potentials and Korean firms have currently high market share but has rather low future potentials.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1478-1482
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• 2005

Since it is a very issue that figures out a current position of mobile robots, various methods have been proposed until nowadays. This paper proposes the sensor model of RFID(Radio Frequency Identification) and position estimation algorithm for mobile robots. We designed the sensor model of RFID in experimenting repeatedly. The sensor model of RFID in this case is that of stochastics according to sensing rate. Based on this stochastic sensor model, we designed the algorithm which estimates distance and direction of RFID tag. Therefore we made sure that RFID tag is used as landmark.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1913-1919
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• 2007

Substantive provisions of the concept of an estimation and safety of complex technical systems are envisaged. New problems are assume orientation to use of the formalized methods of an estimation of residual resources of reliability of objects, and also development of other methodological base in creation of complex technical systems that is connected with detailed elaboration of attention to a safety at all stages of creation of systems: from designing until operation. In this connection existing large objects should be provided by the developed systems of engineering monitoring and diagnostics.

• 전기학회논문지
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• 제62권6호
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• pp.756-761
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• 2013

This paper propose the new demodulation method that can detect resolver signal's peak at the time of position estimation when the position information is required during current controller period. The proposed method is performed in a synchronous demodulation way with exciting signal and also cover a capability which can compensate the lag element of exciting signal caused by the resolver's inductive component and filter circuit. This paper carried out the experiment to investigate the validity and performance of the suggested method by using the test board made up of DSP and demodulation circuit. The test results show that the proposed method is theoretically clear and work completely as expected from making sure of sampling resolver signal's peak at the time of position estimation. In addition, Software position tracking algorithm is executed with the demodulated signals generated by the suggested method and an exact position can be estimated.