• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1998년도 학술발표회 발표논문집
• /
• pp.318-324
• /
• 1998

This study was conducted to derive optimal design floods by Generalized Extreme-value(GEV) distribution for the annual maximum series at ten watersheds along Han, Nagdong, Geum, Yeongsan and Seomjin river systems. Adequacy for the analysis of flood data used in this study was established by the tests of Independence, Homogeneity, detection of Outliers. L-coefficient of variation, L-skewness and L-kurtosis were calculated by L-moment ratio respectively. Parameters were estimated by the Methods of Moments and L-Moments. Design floods obtained by Methods of Moments and L-Moments using different methods for plotting positions in GEV distribution were compared by the relative mean and relative absolute error. It was found that design floods derived by the method of L-moments using weibull plotting position formula in GEV distribution are much closer to those of the observed data in comparison with those obtained by method of moments using different formulas for plotting positions in view of relative mean and relative absolute error.

• Journal of the Korean Statistical Society
• /
• 제33권3호
• /
• pp.323-337
• /
• 2004

This article coined a general class of estimators for various measures in normal population when some' a priori' or guessed value of standard deviation a is available in addition to sample information. The class of estimators is primarily defined for a function of standard deviation. An unbiased estimator and the minimum mean squared error estimator are worked out and the suggested class of estimators is compared with these classical estimators. Numerical computations in terms of percent relative efficiency and absolute relative bias established the merits of the proposed class of estimators especially for small samples. Simulation study confirms the excellence of the proposed class of estimators. The beauty of this article lies in estimation of various measures like standard deviation, variance, Fisher information, precision of sample mean, process capability index $C_{p}$, fourth moment about mean, mean deviation about mean etc. as particular cases of the proposed class of estimators.

• 한국광물학회지
• /
• 제23권1호
• /
• pp.15-23
• /
• 2010

정량X선회절분석법을 이용하여 131개의 제주도 주변해역 표층퇴적물 시료 내에 존재하는 각 점토광물의 절대함량과 점토광물 사이의 상대함량을 구한 후 그 분포 양상을 비교하여 보았다. 절대 함량은 각각 일라이트(0.5~40.5%, 평균 15.3%), 녹니석(0~7.9%, 평균 2.6%), 카올리나이트(0~5.6%, 평균 1%) 이며 공통적으로 한국남해, 제주도의 북서쪽 해역, 제주도 남쪽 먼 해역에서 높다. 점토광물 함량의 합을 100으로 가정하고 구한 상대함량은 각각 일라이트 70.9% (16.7~89%), 녹니석 21.5% (8.4~68.5%), 차올리나이트 7.6% (0~29.3%)이다. 상대함량을 이용하여 분포 양상을 나타낸 결과, 일라이트는 연구해역 북서쪽과 남동쪽, 그리고 제주도의 남서쪽 해역에서 다른 점토광물에 비해 상대적으로 높은 비율로 분포한다. 녹니석은 연구해역 동쪽과 제주도 서쪽에 인접한 해역에서 상대적으로 높은 비율로 분포하며, 카올리나이트는 제주도 서쪽과 남쪽에 인접한 해역과 남쪽 먼 해역에서 상대적으로 높은 비율로 분포한다. 점토광물 절대함량 분포경향은 연구해역 내 점토에서 실트 입자의 세립질퇴적물 분포와 일치한다. 반면, 점토광물 상대함량 분포는 세립질퇴적물 분포와 관련성을 보이지 않는다.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제7권3호
• /
• pp.165-170
• /
• 2007

Recommendation systems provide users with proper services using context information being input from many sensors occasionally under ubiquitous computing environment. But in case there isn't sufficient context information for service recommendation in spite of much context information, there can be problems of resulting in inexact result. In addition, in the quantification step to use context information, there are problems of classifying context information inexactly because of using an absolute classification course. In this paper, we solved the problem of lack of necessary context information for service recommendation by using dynamic profile information. We also improved the problem of absolute classification by using a relative classification of context information in quantification step. As the result of experiments, expectation preference degree was improved by 7.5% as compared with collaborative filtering methods using an absolute quantification method where context information of P2P mobile agent is used.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2005년도 학술발표회 논문집
• /
• pp.194-198
• /
• 2005

Although the rainstorm causes local damage on large scale, it is difficult to predict the movement of the rainstorm exactly. In order to reduce the rainstorm damage of the rainstorm, it is necessary to analyze the path of the rainstorm using various statistical methods. In addition, efficient time interval of rainfall observation for the analysis of the rainstorm movement can be derived by applying various statistical methods to rainfall data. In this study, the rainstorm tracking using statistical method is performed for various types of rainfall data. For the tracking of the rainstorm, the methods of temporal distribution, inclined Plane equations, and cross correlation were applied for various types of data including electromagnetic rainfall gauge data and AWS data. The speed and direction of each method were compared with those of real rainfall movement. In addition, the effective time interval of rainfall observation for the analysis of the rainstorm movement was also investigated for the selected time intervals 10, 20, 30, 40, 50, and 60 minutes. As a result, the absolute relative errors of the method of inclined plane equations are smaller than those of other methods in case of electromagnetic rainfall gauges data. The absolute relative errors of the method of cross correlation are smaller than those of other methods in case of AWS data. The absolute relative errors of 30 minutes or less than 30 minutes are smaller than those of other time intervals.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.1811-1812
• /
• 2008

This paper represents a absolute position tracking system with sensor fusion and PD-gain. this paper presents an accurate localization method by relative and absolute sensor fusion and PD control for position tracking of mobile robot. we developed a sensor based absolution position tracking and smooth moving algorithm using this algorithm.

• 자원환경지질
• /
• 제36권5호
• /
• pp.387-389
• /
• 2003

한반도지역에서 중력 기준점 설치, 기 설치된 중력 기준점의 중력 값들의 정밀도 향상 및 중력가속도 값을 얻기 위하여, 표준연구원(KRISS)은 한 중 공동으로 1996년 10월8일∼11월8일까지, 국립지리원(NGI)은 한$.$일공동으로 1999년 12월10∼16일까지 각각 대전과 수원에서 절대 중력계(Laser Interferometry Absolute Gravimeter type NIM-II와 FG5 Absolute Gravity meter(#203))를 사용하여 절대중력관측을 수행하였다. 표준연구원과 국립지리원이 관측한 절대 중력 값은 각각 979,829.609${\pm}$006 mGal(대전), 979,918.775${\pm}$0.0001 mGal(수원)이다. 앞으로 한반도에서 지구과학분야 활성화를 위해서 더 많은 절대중력 기준점의 확보가 필요하다고 사려된다.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 1998년도 학술발표회 발표논문집
• /
• pp.331-337
• /
• 1998

This study was carried out to derive optimal design floods by Weibull-3 distribution with the annual maximum series at seven watersheds along Man, Nagdong, Geum, Yeongsan and Seomjin river systems. Adequacy for the analysis of flood data used in this study was acknowledged by the tests of Independence, Homogeneity, detection of Outliers. Parameters were estimated by the Methods of Moments and L-Moments. Design floods obtained by Methods of Moments and L-Moments using different methods for plotting positions in Weibull-3 distribution were compared by the rotative mean error and relative absolute error. It has shown that design floods derived by the method of L-moments using Weibull plotting position formula in Weibull-3 distribution are much closer to those of the observed data in comparison with those obtained by method of moments using different formulas for plotting positions in view of relative mean and relative absolute error.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 추계학술대회논문집
• /
• pp.641-648
• /
• 2006

This study investigates which sound quality indices except SPL raise annoyance response. For investigation, auditory perception experiments for road traffic noise with identical linear SPL were performed by Paired Comparison Method. The numerical results of a Paired Comparison experiment express relative preference about annoyance. So that these relative preference scores are to be correlated to sound quality indices, which are absolute, a transformation is required to go from the relative domain to an absolute and linear scale of preference. The results of the transformation will be the 'merit values,' which quantifies the annoyance(in this case) of the road traffic noise on a linear scale. Using multiple regression, a formula is established that can calculate predicted merit values. Furthermore, This investigation offers a method selecting sound samples that represent various sound quality indices values to use experiment.

• 대한원격탐사학회지
• /
• 제35권6_1호
• /
• pp.895-905
• /
• 2019

현재 현업에서 사용되고 있는 상용 무인기 영상처리 소프트웨어는 카메라 캘리브레이션 정보나 영상 전체에 대한 블록 번들조정 정확도만 제공할 뿐 스테레오 페어의 실제 도화 가능여부에 대한 정확도는 거의 제공하지 않는다. 본 논문에서는 무인기 영상처리 소프트웨어에서 산출된 표정요소를 사용하여 도화품질을 산출하고 실제 도화기에 적용하여 도화품질의 신뢰성에 대해서 분석하였다. 도화품질은 Y시차 정확도, 상대모델 정확도, 절대모델 정확도의 3가지 정확도로 정의하였다. Y시차 정확도는 스테레오 페어간 입체시 여부를 판단할 수 있는 정확도이다. 상대모델 정확도는 모델 좌표계 상에서 스테레오 페어간 상대적인 번들조정 정확도이다. 절대모델 정확도는 절대 좌표계에서 번들조정 정확도이다. 실험데이터는 도심지를 대상으로 회전익에서 취득된 GSD 5 cm급의 영상 723장을 사용하여 도화품질을 분석하였다. 연구진이 개발한 기술을 사용해 예측한 상대모델 정확도와 실제 도화기에서 관측한 정확도의 최대오차는 0.11 m로 정밀한 결과를 보여 주었다. 절대모델 정확도도 마찬가지로, 도화기에서 관측한 정확도의 최대오차는 0.16 m로 정밀한 결과를 보여주었다.