• Title/Summary/Keyword: non-local mean

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Efficiency of Aggregate Data in Non-linear Regression

  • Huh, Jib
    • Communications for Statistical Applications and Methods
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    • v.8 no.2
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    • pp.327-336
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    • 2001
  • This work concerns estimating a regression function, which is not linear, using aggregate data. In much of the empirical research, data are aggregated for various reasons before statistical analysis. In a traditional parametric approach, a linear estimation of the non-linear function with aggregate data can result in unstable estimators of the parameters. More serious consequence is the bias in the estimation of the non-linear function. The approach we employ is the kernel regression smoothing. We describe the conditions when the aggregate data can be used to estimate the regression function efficiently. Numerical examples will illustrate our findings.

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A Study on the Interrelation between RAMYON DIET and Condition of Health in the Urban and Rural (도농간(都農間)의 라면식이(食餌)와 건강(健康)상태의 관련성(關聯性)에 관(關)한 연구(硏究))

  • Kim Jin-Won;Lyu Young-Su
    • Journal of Oriental Neuropsychiatry
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    • v.6 no.1
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    • pp.85-94
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    • 1995
  • To find out the difference of local characteristics, body and mental activity of Ramyon's habitual eater,THI guestion which is objects of students of high school in the city and country was carried. The results are as follows: 1.In comparison of eating and non-eating group of both male and female syudents, the mean value of eating group was high and showed the significance(P<0.001). 2. The eating group of city showed the higher mean value than country and it showed the significance(P<0.05). 3. In the eating group of city;the female had higher mean value than the male and showed no significance. In the eating group of city;the female had higher mean value than the male and showed significance(P<0.001). 4. In the eating group of male, the mean value of city was higher than country and showed significance(P<0.001). In the eating group of female, the mean value of city was igher than country, but showed no significance. As the results of the above,se know habitual eating of Ramyon give rise to spleen functional disouder and consepuently mental disorder resulting trom spirit-blood's original impediment and the variety of character, such varieties were different according to the characteristics of local and difference. Therefore, we'll study more detail aspents from now on.

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An Investigation of Heat Transfer Characteristics of Swirling Flow in a 180$^{\circ}$ Circular Section Bend with Uniform Heat Flux

  • Chang, Tae-Hyun
    • Journal of Mechanical Science and Technology
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    • v.17 no.10
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    • pp.1520-1532
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    • 2003
  • An experiment was performed to obtain the local heat transfer coefficient and Nusselt number in a circular duct with a 180$^{\circ}$ bend for Re=6 x 10$^4$, 8 x 10$^4$ and 1 x 10$\^$5/ under swirling flow and non-swirling flow conditions. The test tube with a circular section was made from stainless steel having a curvature ration of 9.4. Current heat flux of 5.11 kW/㎡ was applied to the test tube by electrical power and the swirling motion of air was produced by a tangential inlet to the pipe axis at 180$^{\circ}$. Measurements of local wall temperatures and the bulk mean temperatures of air were made at four circumferential positions at 16 stations. The wall temperatures showed a reduced distribution curve at the bend for the non-swirling flow, but this effect did not appear for the swirling flow. The Nusselt number distributions for the swirling flow, which was calculated from the measured wall and the bulk temperatures, were higher than that of the non-swirling flow. The average Nusselt number of the swirling flow increased by about 90-100%, compared to that of the non-swirling flow. The Nu/Nu$\_$DB/ values at the 90$^{\circ}$ station for non-swirling flow and swirling flow were approximately 2.5 and 4.8 at Re=6x10$^4$ respectively. The values agree well with Said's results for non-swirling flow.

Enhancement of the Ultrasonic Image Using the Adaptive Window Log Filter for NDI of Aircraft Composite Materials (항공기 복합 재료의 비파괴 검사(NDI)를 위한 가변 창 필터를 이용한 초음파 영상 개선)

  • Hong, G.Y.;Hong, S.B.
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.11 no.2
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    • pp.33-42
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    • 2003
  • In this paper, we propose an enhancement of the ultrasonic image for non-destructive inspection of aircraft composite materials. The ultrasonic images are corrupted by a speckle noise which has the characteristic of granular pattern noise and is in all types of coherent imaging systems, the signal independent and multiplicative noise. In this paper, we derive a filter, called the AWLF(Adaptive Window Log Filter), from the nature of the speckle. The filter is made of the MEAN Filter in the edge region and Log Filter in the flat or noise region. To make a distinction between edge and flat region, we calculate the inclination around the local window instead of computing the local statistics of pixels such as local mean ${\bar{M}}$ and standard deviation ${\sigma}_s$. According to the obtained region, edge region is performed by the mean filter and flat region by the Log filter. Performance of the proposed filter is evaluated by the Enhanced Factor$(F_e)$ and the Speckle Index(SI).

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Blending of Contrast Enhancement Techniques for Underwater Images

  • Abin, Deepa;Thepade, Sudeep D.;Maitre, Amulya R.
    • International Journal of Computer Science & Network Security
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    • v.22 no.1
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    • pp.1-6
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    • 2022
  • Exploration has always been an instinct of humans, and underwater life is as fascinating as it seems. So, for studying flora and fauna below water, there is a need for high-quality images. However, the underwater images tend to be of impaired quality due to various factors, which calls for improved and enhanced underwater images. There are various Histogram Equalization (HE) based techniques which could aid in solving these issues. Classifying the HE methods broadly, there is Global Histogram Equalization (GHE), Mean Brightness Preserving HE (MBPHE), Bin Modified HE (BMHE), and Local HE (LHE). Each of these HE extensions have their own pros and cons and thus, by considering them we have considered BBHE, CLAHE, BPDHE, BPDFHE, and DSIHE enhancement algorithms, which are based on Mean Brightness Preserving HE and Local HE, for this study. The performance is evaluated with non-reference performance measures like Entropy, UCIQE, UICM, and UIQM. In this study, we apply the enhancement algorithms on 300 images from the UIEB benchmark dataset and then apply the techniques of cascading fusion on the best-performing algorithms.

An ENG analysis for estimating the individual capabilities of the rectus femoris muscle (EMG 분석을 이용한 대퇴직근의 근력추정)

  • Lee, Myeon-U;Lee, Gu-Hyeong
    • Journal of Korean Institute of Industrial Engineers
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    • v.7 no.2
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    • pp.3-17
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    • 1981
  • Isometric muscle strength has become important as it is realized that a large variation in the human exists and is affected by many personal and environmental factors. Experiments have been performed for estimating the individual capabilities of the quadriceps femoris muscle in man. The surface EMG has been recorded on the belly of the rectus femoris muscle during voluntary isometric continuous exertion at 25%, 50%, 75%, and 100% MVC. As a muscle force (% MVC) increases, the rectified mean EMG amplitude increases in a non-linear form. The rectified mean EMG amplitude also increases in a non-linear with respect to fatigue progression. As the muscle force (% MVC) increases, an endurance time of isometric exertion decreases linearly. Analysis shows that rectified mean EMG amplitude is a consistent and sensitive measure of motor unit recruitments and can be useful in estimating an individual capability of a local muscle. Further, the result satisfies the sufficient condition that type S motor units are recruited first, while large motor units are recruited progressively as the fatigue develops.

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A study on the necessity of oral health promotion program for children visiting local child care centers: the case of Incheon (지역아동센터 방문아동을 위한 구강건강증진 프로그램 필요에 대한 연구 -인천광역시를 중심으로-)

  • Han, Su-Jin;Hwang, Yoon-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.7 no.1
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    • pp.91-103
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    • 2007
  • The purpose of this study was to pave the way for the development of oral health promotion programs for children from the low-income class. The subjects in this study were 322 children from the city of Incheon. Some of them visited local childcare centers, and the others attended six different adjacent elementary schools. Their awareness of oral health, oral health behavior and preventive-treatment experience were investigated in May 2005, and whether there were any characteristics in their visit of dental institutions was checked. Besides, whether their parents advised them to brush their teeth before turning in was examined. The findings of the study were as follows: 1. 22.0 percent of the children investigated were visiting local childcare centers, and 78.0 percent weren't. The guardians of the former group largely received high-school(50.7%) and middle-school or lower education(22.5%), and those of the latter group mostly received high-school(41.0%) and college- or higher education(35.5%)(pE0.001). The common monthly mean house-hold income of the former was one million won or less(54.9%) or ranged from 1.01 to 2.00 million won(19.7%), and the most prevalent monthly mean household income of the latter was between 2.01 and 3.50 million won(28.7%). The second most dominant monthly mean household income of the latter ranged from 1.01 to 2.00 million won(28.3%), and the third most common one was 3.50 million won or more(12.0%)(pE0.001). 2. The most prevalent daily toothbrushing frequency among the local childcare center visitors was twice(39.4%), followed by three times(19.7%). The third largest group of the visitors brushed their teeth after each meal(19.7%). The most dominant daily toothbrushing frequency among the non-users of local child care centers was twice(54.2%), followed by three times(29.1%)(pE0.01). As to the way of toothbrushing, 58.2 percent of the visitors and 74.9 percent of the non-visitors brushed their teeth by turning their toothbrush or up and down(pF0.05). 62.0 percent of the former and 74.9 percent of the latter always brushed their teeth before turning in, and whether they visited local childcare centers made a significant difference to that(pE0.05). 3. 69.7 percent of the non-visitors were always advised by their parents to do toothbrushing before turning in, and the visitors who were given the same advice all the time numbered 29.6 percent(pE0.001). 4. 56.4 percent of the visitors and 72.1 percent of the non-visitors had ever visited dental institutions over the past year. Dental hospitals and clinics were identified as the dental institutions that they visited the most, and they mostly received dental-caries treatment or had a tooth out there. 49.3 percent of the visitors and 35.1 percent of the non-visitors had ever had a toothache. 5. Sealant was experienced by 42.3 percent of the visitors and 46.2 percent of the non-visitors to prevent dental caries(pF0.05). 33.8 percent of the visitors underwent fluoride application, and that rate was higher than that of the non-visitors with the same experience that stood at 22.7 percent(pE0.05). The visitors mainly acquired knowledge on oral health through other channels that weren't specified in the questionnaire(28.2%), and the non-visitors did it mostly at dental clinics(39.0%)(pE0.001).

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Analysis of BOD Mean Concentration and Confidence Interval using Bootstrap Technique (Bootstrap 기법을 이용한 BOD 평균 농도 및 신뢰구간 분석)

  • Kim, Kyung Sub
    • Journal of Korean Society on Water Environment
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    • v.26 no.2
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    • pp.297-302
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    • 2010
  • It is very important to know mean and confidence interval of water-quality constituents such as BOD for water-quality control and management of rivers and reservoirs effectively. The mean and confidence interval of BOD at Anseong2 and Hwangguji3 sampling stations which are located at the border of local governments in Anseong Stream were estimated and analyzed in this paper using Bootstrap technique which is one of non-parametric statistics. The results of Bootstrap were compared with arithmetic mean, geometric mean, Biweight method mean as a point estimator and distribution mean came from the appropriate probability distribution of Log-normal. In Bootstrap technique 12 data set was randomly selected in each year and 1000 samples was produced to get parameter of population. Visual Basic for Applications (VBA) of Microsoft Excel was utilized in Bootstrap. It was revealed that the Bootstrap technique can be used to explain more rigorously and robustly the achievement or violation of BOD target concentration in Total Maximum Daily Load (TMDL).

Smoke Detection Method Using Local Binary Pattern Variance in RGB Contrast Imag (RGB Contrast 영상에서의 Local Binary Pattern Variance를 이용한 연기검출 방법)

  • Kim, Jung Han;Bae, Sung-Ho
    • Journal of Korea Multimedia Society
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    • v.18 no.10
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    • pp.1197-1204
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    • 2015
  • Smoke detection plays an important role for the early detection of fire. In this paper, we suggest a newly developed method that generated LBPV(Local Binary Pattern Variance)s as special feature vectors from RGB contrast images can be applied to detect smoke using SVM(Support Vector Machine). The proposed method rearranges mean value of the block from each R, G, B channel and its intensity of the mean value. Additionally, it generates RGB contrast image which indicates each RGB channel’s contrast via smoke’s achromatic color. Uniform LBPV, Rotation-Invariance LBPV, Rotation-Invariance Uniform LBPV are applied to RGB Contrast images so that it could generate feature vector from the form of LBP. It helps to distinguish between smoke and non smoke area through SVM. Experimental results show that true positive detection rate is similar but false positive detection rate has been improved, although the proposed method reduced numbers of feature vector in half comparing with the existing method with LBP and LBPV.

Rain Detection and Removal Algorithm using Motion-Compensated Non-local Means Filter for Video Sequences (동영상을 위한 움직임 보상 기반 Non-Local Means 필터를 이용한 우적 검출 및 제거 알고리즘)

  • Seo, Seung Ji;Song, Byung Cheol
    • Journal of Broadcast Engineering
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    • v.20 no.1
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    • pp.153-163
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    • 2015
  • This paper proposes a rain detection and removal algorithm that is robust against camera motion in video sequences. In detection part, the proposed algorithm initially detects possible rain streaks by using intensity properties and spatial properties. Then, the rain streak candidates are selected based on Gaussian distribution model. In removal part, a non-rain block matching algorithm is performed between adjacent frames to find similar blocks to the block that has rain pixels. If the similar blocks to the block are obtained, the rain region of the block is reconstructed by non-local means (NLM) filter using the similar neighbors. Experimental results show that the proposed algorithm outperforms the previous works in terms of subjective visual quality of de-rained video sequences.