• Title/Summary/Keyword: Coefficient of Correlation Weighting method

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A Study on the Reviesd Methods of Missing Rainfall Data for Real-time Forecasting Systems (실시간 예보 시스템을 위한 우량자료 보정 기법 연구)

  • Han, Myoung-Sun;Kim, Chung-Soo;Kim, Hyoung-Seop;Kim, Hwi-Rin
    • Journal of Korea Water Resources Association
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    • v.42 no.2
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    • pp.131-139
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    • 2009
  • The weather accidents by global warming effect are increasing rapidly whole world. Flood forcasting system and hydrological database are operated by almost all the countries in the world. An objective of this study is to research revised methods of missing rainfall data and find more effective revised method for this operating system. 194 rainfall data of the Han river basin is used. Arithmetic average method, coefficient of correlation weighting method and inverse distance weighting method are compared to estimate revised methods. The result from the analysis shows that coefficient of correlation weighting method is best quantitatively among the 3 methods.

Comparison of Dietary Methods in Nutritional Studies (식사섭취조사방법의 비교연구)

  • 김혜경
    • Journal of Nutrition and Health
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    • v.22 no.1
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    • pp.23-31
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    • 1989
  • The purpose of this study was to evaluate the validity of various dietary methods. Dietary intake of 24 patients on regular diet was investigated by three methods. One method was a precise weighing method, the others were 24-hour dietary recall method and convenient dietary questionnaries. The results obtained are summarized as followes ; 1) There were no significant differences in mean nutrient intake of subjects among three dietary survey methods. 2) The validity coefficient between the precise weighing method and 24-hour recall method, ranging from 0.26(fat) to 0.59(carbohydrate) showed significant correlation for carbohydrate, vitamin A, thiamin, riboflavin and ascorbic and intakes. 3) The validity coefficient between precise weighting method and covenient dietary questionnaires, ranging from 0.14(fat) to 0.80(vitamin A), showed a significant correlation for most nutrients. 4) Female showed higher correlation between the precise weighing method and 24-hour recall method than male subjects for most nutrients. However, there was no significant sexual difference of correlation between weighing method and convenient method. 5) The correlation coefficient between the precise weighing method and the other two methods by age group showed younger sujbects have a higher significant correlation than older subjects for most nutrients.

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Study on the Method of Development of Road Flood Risk Index by Estimation of Real-time Rainfall Using the Coefficient of Correlation Weighting Method (상관계수가중치법을 적용한 실시간 강우량 추정에 따른 도로 침수위험지수 개발 방법에 대한 연구)

  • Kim, Eunmi;Rhee, Kyung Hyun;Kim, Chang Soo
    • Journal of Korea Multimedia Society
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    • v.17 no.4
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    • pp.478-489
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    • 2014
  • Recently, flood damage by frequent localized downpours in cities are on the increase on account of abnormal climate phenomena and growth of impermeable area by urbanization. In this study, we are focused on flooding on roads which is the basis of all means of transportation. To calculate real-time accumulated rainfall on a road link, we use the Coefficient of Correlation Weighting method (CCW) which is one of the revised methods of missing rainfall as we consider a road link as a unobserved rainfall site. CCW and real-time accumulated rainfall entered through the Internet are used to estimate the real-time rainfall on a road link. Together with the real-time accumulated rainfall, flooding history, rainfall range causing flooding of a road link and frequency probability precipitation for road design are used as factors to determine the Flood Risk Index on roads. We simulated two cases in the past, July, 7th, 2009 and July, 15th, 2012 in Busan. As a result, all of road links included in the actual flooded roads at that time got the high level of flood risk index.

Correlation of Single-Number Ratings for Sound Insulation by Floor Impact (바닥충격음 차단성능 단일수치 평가방법별 상관성에 대한 조사연구)

  • 김흥식;김명준;김하근
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.719-723
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    • 2002
  • The purpose of this study is to suggest the correlation of single-number ratings for sound insulation by floor impact. As a assessment method of impact sound insulation. we selected the IIC contour of ISO, A weighted sound level. Inverse A-weighting curve and L-Index of japanese industrial standard. And we estimated the single-number ratings by application the measured data of impact sound level to each method. The results showed that the coefficients of determination between each two single-number ratings were very high (more than 0.9169). And In the condition of same assessment method, the coefficient of determination for light-weight impact sound was higher than that for heavy-weight impact sound.

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Kernel Regression with Correlation Coefficient Weighted Distance (상관계수 가중법을 이용한 커널회귀 방법)

  • Shin, Ho-Cheol;Park, Moon-Ghu;Lee, Jae-Yong;You, Skin
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.588-590
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    • 2006
  • Recently, many on-line approaches to instrument channel surveillance (drift monitoring and fault detection) have been reported worldwide. On-line monitoring (OLM) method evaluates instrument channel performance by assessing its consistency with other plant indications through parametric or non-parametric models. The heart of an OLM system is the model giving an estimate of the true process parameter value against individual measurements. This model gives process parameter estimate calculated as a function of other plant measurements which can be used to identify small sensor drifts that would require the sensor to be manually calibrated or replaced. This paper describes an improvement of auto-associative kernel regression by introducing a correlation coefficient weighting on kernel distances. The prediction performance of the developed method is compared with conventional auto-associative kernel regression.

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Two Wheeler Recognition Using the Correlation Coefficient for Histogram of Oriented Gradients to Apply Intelligent Wheelchair (지능형 휠체어 적용을 위한 기울기 히스토그램의 상관계수를 이용한 도로위의 이륜차 인식)

  • Kim, Bum-Koog;Park, Sang-Hee;Lee, Yeung-Hak;Lee, Gang-Hwa
    • Journal of Biomedical Engineering Research
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    • v.32 no.4
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    • pp.336-344
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    • 2011
  • This article describes a new recognition algorithm using correlation coefficient for intelligent wheelchair to avoid collision for elderly or disabled people. The correlation coefficient can be used to represent the relationship of two different areas. The algorithm has three steps: Firstly, we extract an edge vector using the Histogram of Oriented Gradients(HOG) which includes gradient information and unique magnitude for each cell. From this result, the correlation coefficients are calculated between one cell and others. Secondly, correlation coefficients are used as the weighting factors for normalizing the HOG cell. And finally, these features are used to classify or detect variable and complicated shapes of two wheelers using Adaboost algorithm. In this paper, we propose a new feature vectors which is calculated by weighted cell unit to classify with multiple view-based shapes: frontal, rear and side views($60^{\circ}$, $90^{\circ}$ and mixed angle). Our experimental results show that two wheeler detection system based on a proposed approach leads to a higher detection accuracy than the method using traditional features in a similar detection time.

New Approach to Two-wheeler Detection using Correlation Coefficient based on Histogram of Oriented Gradients

  • Lee, Yeunghak;Shim, Jaechang
    • Journal of Multimedia Information System
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    • v.3 no.4
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    • pp.119-128
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    • 2016
  • This study aims to suggest a new algorithm for detecting two-wheelers on road that have various shapes according to the viewing angle for vision based intelligent vehicles. This article describes a new approach to two-wheelers detection algorithm riding on people based on modified Histogram of Oriented Gradients (HOG) using correlation coefficient (CC). The CC between two local area variables, in which one is the person riding a bike and other is its background, can represent correlation relation. First, we extract edge vectors using HOG which includes gradient information and differential magnitude as cell based. And then, the value, which is calculated by the CC between the area of each cell and one of two-wheelers, can be extracted as the weighting factor in process for normalizing the modified HOG cell. This paper applied the Adaboost algorithm to make a strong classification from weak classification. In this experiment, we can get the result that the detection rate of the proposed method is higher than that of the traditional method.

Two-wheeler Detection System using Histogram of Oriented Gradients based on Local Correlation Coefficients and Curvature

  • Lee, Yeunghak;Kim, Taesun;Shim, Jaechang
    • Journal of Multimedia Information System
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    • v.2 no.4
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    • pp.303-310
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    • 2015
  • Vulnerable road users such as bike, motorcycle, small automobiles, and etc. are easily attacked or threatened with bigger vehicles than them. So this paper suggests a new approach two-wheelers detection system riding on people based on modified histogram of oriented gradients (HOGs) which is weighted by curvature and local correlation coefficient. This correlation coefficient between two variables, in which one is the person riding a bike and other is its background, can represent correlation relation. First, we extract edge vectors using the curvature of Gaussian and Histogram of Oriented Gradients (HOG) which includes gradient information and differential magnitude as cell based. And then, the value, which is calculated by the correlation coefficient between the area of each cell and one of bike, can be used as the weighting factor in process for normalizing the HOG cell. This paper applied the Adaboost algorithm to make a strong classification from weak classification. The experimental results validate the effectiveness of our proposed algorithm show higher than that of the traditional method and under challenging, such as various two-wheeler postures, complex background, and even conclusion.

Image Signal Denoising by the Soft-Threshold Technique Using Coefficient Normalization in Multiwavelet Transform Domain (멀티웨이블릿 변환영역에서 계수정규화를 이용한 Soft-Threshold 기법의 영상신호 잡음제거)

  • Kim, Jae-Hwan;Woo, Chang-Yong;Park, Nam-Chun
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.4
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    • pp.255-265
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    • 2007
  • In case of wavelet coefficients have correlation, in image signal denoising using wavelet shrinkage denoising method, the denoising effect for the image signal is reduced when the wavelet shrinkage denoising method is used. The coefficients of multiwavelet transform have correlation by pre-filters. To solve the degradation problem in multiwavelet transform, V Sterela suggested a new pre-filter for the Universal threshold or weighting factors to the threshold. In this paper, to improve the denoising effect in the multiwavelet transform, the coefficient normalizing method that the coefficient are divided by estimated noise deviation is adopted to the transformed multiwavelet coefficients in the course of wavelet shrinkage technique. And the thresholds of universal, SURE and GCV are estimated using normalized coefficients and tried to denoise by the wavelet shrinkage technique. We compared PSNRs of denoised images for each thresholds and confirmed the efficiency of the proposed method.

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Application of a Statistical Interpolation Method to Correct Extreme Values in High-Resolution Gridded Climate Variables (고해상도 격자 기후자료 내 이상 기후변수 수정을 위한 통계적 보간법 적용)

  • Jeong, Yeo min;Eum, Hyung-Il
    • Journal of Climate Change Research
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    • v.6 no.4
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    • pp.331-344
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    • 2015
  • A long-term gridded historical data at 3 km spatial resolution has been generated for practical regional applications such as hydrologic modelling. However, overly high or low values have been found at some grid points where complex topography or sparse observational network exist. In this study, the Inverse Distance Weighting (IDW) method was applied to properly smooth the overly predicted values of Improved GIS-based Regression Model (IGISRM), called the IDW-IGISRM grid data, at the same resolution for daily precipitation, maximum temperature and minimum temperature from 2001 to 2010 over South Korea. We tested various effective distances in the IDW method to detect an optimal distance that provides the highest performance. IDW-IGISRM was compared with IGISRM to evaluate the effectiveness of IDW-IGISRM with regard to spatial patterns, and quantitative performance metrics over 243 AWS observational points and four selected stations showing the largest biases. Regarding the spatial pattern, IDW-IGISRM reduced irrational overly predicted values, i. e. producing smoother spatial maps that IGISRM for all variables. In addition, all quantitative performance metrics were improved by IDW-IGISRM; correlation coefficient (CC), Index Of Agreement (IOA) increase up to 11.2% and 2.0%, respectively. Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were also reduced up to 5.4% and 15.2% respectively. At the selected four stations, this study demonstrated that the improvement was more considerable. These results indicate that IDW-IGISRM can improve the predictive performance of IGISRM, consequently providing more reliable high-resolution gridded data for assessment, adaptation, and vulnerability studies of climate change impacts.