• Title/Summary/Keyword: mean-variance

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Sensory Profiling of Commercial Korean Distilled Soju (시판 증류식 소주의 관능특성 분석)

  • Lee, Seung-Joo;Park, Cheon-Soo;Kim, Ho-Kyung
    • Korean Journal of Food Science and Technology
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    • v.44 no.5
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    • pp.648-652
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    • 2012
  • The sensory characteristics of nine commercially distilled soju samples were determined by sensory descriptive analysis. Eight aroma attributes, as well as four flavor/taste attributes, and six mouth-feel related attributes were evaluated by 9 judges. The descriptive data set was initially analyzed for a significant overall product effect by employing a three-way mixed model analysis of variance (judges, samples, and replications) as well as two-way interactions, with judges treated as random. In addition, correlations between mean attribute ratings were calculated, and a principal component analysis (PCA) of the mean attribute ratings employing the covariance matrix was conducted. Based on the PCA, distilled soju samples were primarily separated along the first principal component, which accounted for 66% of the total variance between the samples, with high intensities of 'alcohol taste' and 'alcohol aroma' versus 'yeast aroma'. The second principal component accounted for 14% of the total variance. Soju containing high alcohol showed stronger intensities of 'bitterness', 'alcohol taste', 'alcohol aroma', as well as all mouth-feel attributes.

A Study on Uncertainty of Risk of Failure Based on Gumbel Distribution (Gumbel 분포형을 이용한 위험도에 관한 불확실성 해석)

  • Heo Jun-Haeng;Lee Dong-Jin;Shin Hong-Joon;Nam Woo-Sung
    • Journal of Korea Water Resources Association
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    • v.39 no.8 s.169
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    • pp.659-668
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    • 2006
  • The uncertainty of the risk of failure of hydraulic structures can be determined by estimating the variance of the risk of failure based on the methods of moments, probability weighted moments, and maximum likelihood assuming that the underlying model is the Gumbel distribution. In this paper, the variance of the risk of failure was derived. Monte Carlo simulation was peformed to verify the characteristics of the derived formulas for various sample size, design life, nonexceedance probability, and variation coefficient. As the results, PWM showed the smallest relative bias and root mean square error than the others while ML showed the smallest ones for relatively large sample siBes regardless of design life and nonexceedance probability. Also, it was found that variation coefficient does not effect on the relative bias and relative root mean square error.

Predicting Quality of Life in People with Cancer (추후관리 암환자의 삶의 질 영향요인 분석)

  • 오복자
    • Journal of Korean Academy of Nursing
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    • v.27 no.4
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    • pp.901-911
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    • 1997
  • The purpose of this study is to provide a basis for nursing intervention strategies to promote quality of life in cancer patients. Therefore the study is designed to evaluate the effectiveness of perceived health status, self-esteem, health locus of control, self-efficacy, perceived susceptibility /severity, health promoting behaviors, and hope for quality of life. The sample was composed of 164 stomach cancer patients who visited outpatient clinics at a university hospital in Seoul. The following instruments were used in the study after some adaptation : Lawstone and others' Health Self-rating Scale, Rosenberg's Self-esteem Scale, Wallston and others 'Multidimensional Health Locus of Control Scale, Sherer & Maddux's Self-efficacy Scale, Moon's Health Beliefs Scale, Walker and others' Health Promoting Lifestyle Profile, Nowotney's Hope scale and Noh's Quality of Life Scale. Data were analyzed using a SAS program for Pearson correlation coefficients, descriptive correlational statistics and stepwise multiple regression. The results are as follows : 1. The scores on the quality of life scale ranged from 115 to 243 with a mean of 177.84(SD : 25.35). The mean scores(range 1-5) on the different dimensions were : emotional state 3.37 : economic life 3.47 : physical state & function 3.52 : self-esteem 3.66 : relationship with neighbors 3.37 ; family relationships 3.80. 2. There was a significant correlation between all the predictive variables and the quality of life (r=.20-.65, p<.01). 3. Stepwise multiple regression analysis showed that : 1) Self-esteem was the main predictor of quality of life and accounted for 46.9% of the variance in quality of life. 2) Perceived health status, hope and perceived susceptibility/severity accounted for 11.8%, 8.3%, 1.5% of the variance in quality of life, respectively. 3) Self-esteem, perceived health status, hope & perceived susceptibility /severity combined accounted for 68.5% of the variance in quality of life. In conclusion, self-esteem, perceived health status, hope and perceived susceptibility / severity were identified as important variables in the quality of life of cancer patients.

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Small Target Detection Method Using Bilateral Filter Based on Surrounding Statistical Feature (주위 통계 특성에 기초한 양방향 필터를 이용한 소형 표적 검출 기법)

  • Bae, Tae-Wuk;Kim, Young-Taeg
    • Journal of Korea Multimedia Society
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    • v.16 no.6
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    • pp.756-763
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    • 2013
  • Bilateral filter (BF), functioning by two Gaussian filters, domain and range filter is a nonlinear filter for sharpness enhancement and noise removal. In infrared (IR) small target detection field, the BF is designed by background predictor for predicting background not including small target. For this, the standard deviations of the two Gaussian filters need to be changed adaptively in background and target region of an infrared image. In this paper, the proposed bilateral filter make the standard deviations changed adaptively, using variance feature of mean values of surrounding block neighboring local filter window. And, in case the variance of mean values for surrounding blocks is low for any processed pixel, the pixel is classified to flat background and target region for enhancing background prediction. On the other hand, any pixel with high variance for surrounding blocks is classified to edge region. Small target can be detected by subtracting predicted background from original image. In experimental results, we confirmed that the proposed bilateral filter has superior target detection rate, compared with existing methods.

Volume Transport on the Texas-Louisiana Continental Shelf

  • Cho Kwang-Woo
    • Fisheries and Aquatic Sciences
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    • v.1 no.1
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    • pp.48-62
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    • 1998
  • Seasonal volume transport on the Texas-Louisiana continental shelf is investigated in terms of objectively fitted transport streamfunction fields based on the current meter data of the Texas­Louisiana Shelf Circulation and Transport Processes Study. Adopted here for the objective mapping is a method employing a two-dimensional truncated Fourier representation of the streamfunction over a domain, with the amplitudes determined by least square fit of the observation. The fitting was done with depth-averaged flow rather than depth-integrated flow to reduce the root-mean-square error. The fitting process filters out $11\%$ of the kinetic energy in the monthly mean transport fields. The shelf-wide pattern of streamfunction fields is similar to that of near-surface velocity fields over the region. The nearshore transport, about 0.1 to 0.3 Sv $(1 Sv= 10^6\;m^3/sec)$, is well correlated with the seasonal signal of along-shelf wind stress. The spring transport is weak compared to other seasons in the inner shelf region. The transport along the shelf break is large and variable. In the southwestern shelf break, transport amounts up to 4.7 Sv, which is associated with the activities of the encroaching of energetic anticyclonic eddies originated in Loop Current of the eastern Gulf of Mexico. The first empirical orthogonal function (EOF) of streamfunction variability contains $67.3\%$ of the variance and shows a simple, shelf-wide, along-shelf pattern of transport. The amplitude evolution of the first EOF is highly correlated (correlation coefficient: 0.88) with the evolution of the along-shelf wind stress. This provides strong evidence that the large portion of seasonal variation of the shelf transport is wind-forced. The second EOF contains $23.7\%$ of the variance and shows eddy activities at the southwestern shelf break. The correlation coefficient between the amplitudes of the second EOF and wind stress is 0.42. We assume that this mode is coupled a periodic inner shelf process with a non-periodic eddy process on the shelf break. The third EOF (accounting for $7.2\% of the variance) shows several cell structures near the shelf break associated with the variability of the Loop Current Eddies. The amplitude time series of the third EOF show little correlation with the along-shelf wind.

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A Bitrate Control considering Interframe Variance of Image for H.264/AVC (화면간 영상 변화량을 고려한 H.264/AVC 비트율 제어 방법)

  • Son Nam-Rye;Lee Guee-Sang
    • The KIPS Transactions:PartB
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    • v.13B no.3 s.106
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    • pp.245-254
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    • 2006
  • In this work, a new rate control algorithm for transmission of H.264/AVC video bit stream through CBR(constant bit rate) channel is proposed. The proposed algorithm predicts target bit rate and MAD(mean of absolute difference) for current frame considering image complexity variance between neighboring backward and current images. In details, respective linear regression analysis for MAD and encoded bit rate against image complexity variance produce correlation parameters. Additionally, it uses frame skip technique to maintain bit stream within a manageable range and protect buffer from overflow or underflow. Implementation and experimental results show that the proposed algorithm can provide accurate bit allocation, and can effectively visual degradation after scene changes. Also our proposed algorithm encodes the video sequences with less frame skipping compared to the existing rate control for H.264/AVC.

A New Process for the Requirements Based Aerospace System Design and Optimization (요구도 기반 항공우주 시스템 강건최적설계 기법 연구)

  • Park, Hyeong-Uk;Lee, Jae-Woo;Byun, Yung-Hwan;Chung, Joon;Behdinan, Karman
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.37 no.3
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    • pp.255-266
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    • 2009
  • In this study, a robust aerospace system design process for the aerospace system is developed by considering the uncertainties of user requirements, manufacturing errors, and operational environment variation. User requirements are analyzed and quantified by decision making models and system engineering methods to select alternative concepts which satisfies the various requirements. Robust design and optimization method is applied to derive the robust solution of the selected system. First, a variance of objective function is calculated, and a mean value and a variance of target value are determined by the deterministic design optimization results of the system. A robust optimum design formulation is then needed to derive the robust solution that minimizes the variance of the response and moves the mean values to the target value. It is applied to Very Light Jet (VLJ) aircraft to which much attention is paid recently in civil aerospace market.

Mean estimation of small areas using penalized spline mixed-model under informative sampling

  • Chytrasari, Angela N.R.;Kartiko, Sri Haryatmi;Danardono, Danardono
    • Communications for Statistical Applications and Methods
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    • v.27 no.3
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    • pp.349-363
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    • 2020
  • Penalized spline is a suitable nonparametric approach in estimating mean model in small area. However, application of the approach in informative sampling in a published article is uncommon. We propose a semiparametric mixed-model using penalized spline under informative sampling to estimate mean of small area. The response variable is explained in terms of mean model, informative sample effect, area random effect and unit error. We approach the mean model by penalized spline and utilize a penalized spline function of the inclusion probability to account for the informative sample effect. We determine the best and unbiased estimators for coefficient model and derive the restricted maximum likelihood estimators for the variance components. A simulation study shows a decrease in the average absolute bias produced by the proposed model. A decrease in the root mean square error also occurred except in some quadratic cases. The use of linear and quadratic penalized spline to approach the function of the inclusion probability provides no significant difference distribution of root mean square error, except for few smaller samples.

A Study on Amount of Information Search and Consumer's Post-purchase Satisfaction according to Consumer Information Sources (소비자 정보원에 따른 정보탐색량과 구매후 만족에 관한 연구 -서울특별시 주부 소비자의 냉장고 구매를 중심으로-)

  • Lee, Il-Kyoung;Rhee, Kee-Choon
    • Journal of Families and Better Life
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    • v.10 no.1 s.19
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    • pp.27-42
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    • 1992
  • This study focused on consumer information search activity and consumer's post-purchase satisfaction. For these purpose, a survey was conducted suing questionaires on 430 homemakers that lived in seoul. Statistics used for data were Frequency Distribution. Percentile, Mean, One-way AAANOVA., Scheffe-test, T-test, Pearson's correlation. Multiple Regression Analysis and Multiple Classification Analysis. The major findings were ; 1) The level of each amount information search was lower than average. And the level of consumer's post-purchase satisfaction was a little higher than average. 2) On amount of "noncommercial-personal" information search, the influencing variables were desire to seek information, education, brand royalty in turn. These three variables explained 7% of dependent variable's variance. 3) On amount of "noncommercial-media" information search, the influencing variables were desire to seek information, amount of internal information, education, occupational status in turn. These variables explained 14% of dependent variable's variance. 4) On amount of "commercial-personal" information search, the influencing variable was desire to seek information, and this variable explained 3.1% of dependent variable'a variance. 5) On amount of "commercial-media" information search, the influencing variables were desire to seek information, education, amount of internal information in turn. These three variables explained 12.1% dependent variable's variance. 6) Resulting from multiple classification analysis, influencing variables on consumer's post-purchase satisfaction were amount of noncommercial-media information search and printed media search, and brand royalty. These three variables explained 9% of dependent variable's variance. Furthermore, througout all the subareas of consumer's satisfaction, the amount of noncommercial-media information search was the most influencing variable.

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Image Thresholding Based on Within-Class Standard Deviation (클래스 내 표준편차 기반의 문턱치 처리에 의한 영상분할)

  • Sung, Jung-Min;Ha, Ho-Gun;Choi, Bong-Yeol
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.7
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    • pp.216-224
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    • 2013
  • The within-class variance of Otsu's method is moderate but improper in expressing class statistical distributions. Otsu's method uses a variance to represent the distribution of each class. The variance utilizes a distance square from the mean to a data. This process is not proper in denoting a real class statistical distribution because of the distance square. In this paper, to express more exact class statistical distributions, the within-class standard deviation as a criterion for threshold selection is proposed and then the optimal threshold is determined by minimizing it. In order to have validity, it is shown through the experimental results that the proposed method was more superior to the counterparts.