• Title/Summary/Keyword: Loss

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Review on Predictors of Weight Loss in Obesity Treatment (비만 치료에 있어서 체중 감량에 영향을 주는 인자들에 대한 고찰)

  • Nam, Seung-Hee;Kim, Seo-Young;Lim, Young-Woo;Park, Young-Bae
    • Journal of Korean Medicine for Obesity Research
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    • v.18 no.2
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    • pp.115-127
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    • 2018
  • Objectives: People often fail to reduce or maintain their weight despite trying to lose weight. The purpose of this study was to review previously published study results of the predictive factors associated with weight loss in obesity treatment. Methods: Authors searched for the articles related to weight loss, published from 2007 to 2017 found on PubMed, Scopus, Research Information Sharing Service (RISS), and Koreanstudies Information Service System (KISS). A total of 43 articles were finally selected. From the study results, unchangeable and changeable predictors were extracted, and these predictors were examined according to detailed categories. Results: Predictors of weight loss in obesity treatment included genetic and physiological factors, demographic factors, history of treatment on obesity related factors, behavioral factors, psychological factors and treatment process related factors. The main factors of weight loss were unchangeable predictors such as high initial degree of obesity and younger age, and changeable predictors such as dietary restraint, regular exercise, self-efficacy, initial weight loss and attendance. Especially dietary restraint, regular exercise, successful initial weight loss and high attendance were considered to be dominant factors for weight loss treatments. Conclusions: Our review results suggest that unchangeable and changeable predictors of weight loss should be carefully examined during treatments of obesity.

A Study on Internal Loss Analysis of Totem Pole Bridgeless PFC and Efficiency Improvement using Parallel Switch (토템폴 브릿지리스 PFC의 내부 손실 분석과 병렬 스위치를 사용한 효율 개선에 관한 연구)

  • Yoo, Jeong Sang;Gil, Yong Man;Yu, Seung Hyup;Ahn, Tae Young
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.4
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    • pp.22-27
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    • 2020
  • In this paper, a generalized efficiency equation was proposed to estimate the internal loss of the SMPS (switched-mode power supply) with 3 variables. The first variable was an internal loss not related to the load current such as auxiliary power, the second was a loss proportional to the current such as diode loss, and the third was a loss proportional to square of the current such as conduction loss. Especially, theoretical internal losses of the totem pole bridgeless PFC which is widely used for high efficiency SMPS were expressed as output function to compare generalized efficiency equation. In addition, in order to reduce the conduction loss of the switch, when a multiple switch were paralleled, the correlation with the efficiency was analyzed and shown as a graph. In order to confirm the degree of the parallel switch structure on the efficiency improvement, a 2kW class totem pole bridgeless PFC was constructed and the effectiveness of the analysis was confirmed by comparing the generalized efficiency equation and theoretical loss analysis results with experimental data.

Millimeter-wave diffraction-loss model based on over-rooftop propagation measurements

  • Kim, Kyung-Won;Kim, Myung-Don;Lee, Juyul;Park, Jae-Joon;Yoon, Young Keun;Chong, Young Jun
    • ETRI Journal
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    • v.42 no.6
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    • pp.827-836
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    • 2020
  • Measuring the diffraction loss for high frequencies, long distances, and large diffraction angles is difficult because of the high path loss. Securing a well-controlled environment to avoid reflected waves also makes long-range diffraction measurements challenging. Thus, the prediction of diffraction loss at millimeter-wave frequency bands relies on theoretical models, such as the knife-edge diffraction (KED) and geometrical theory of diffraction (GTD) models; however, these models produce different diffraction losses even under the same environment. Our observations revealed that the KED model underestimated the diffraction loss in a large Fresnel-Kirchhoff diffraction parameter environment. We collected power-delay profiles when millimeter waves propagated over a building rooftop at millimeter-wave frequency bands and calculated the diffraction losses from the measurements while eliminating the multipath effects. Comparisons between the measurements and the KED and GTD diffraction-loss models are shown. Based on the measurements, an approximation model is also proposed that provides a simple method for calculating the diffraction loss using geometrical parameters.

The AC loss of 22.9kV/50MVA High-Tc Superconducting Power Cable (22.9kV/50MVA급 고온초전도 전력케이블의 교류손실)

  • Choi, Suk-Jin;Lee, Sang-Jin;Sim, Ki-Deok;Cho, Jeon-Wook;Lee, Soo-Gil;Yang, Byeong-Mo;Yoon, Hyung-Hee
    • Progress in Superconductivity and Cryogenics
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    • v.11 no.3
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    • pp.31-34
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    • 2009
  • An HTS power cable is generally composed of 2 layers for conducting and 1 layer for shielding. For the analysis of AC loss of an HTS power cable, 2-dimensional magnetic field analysis is carried out. The magnetization loss in HTS cable core was calculated, and the transport current loss was obtained from the monoblock equation and the elliptical Norris Equation. And the total AC loss of the cable was expected by the sum of magnetization loss and transport current loss. The variation of ac loss with respect to the gap and uncertain factor between the superconducting tapes was investigated, and the ac loss of 22.9kV/50MVA high-Tc superconducting power cable was calculated. These results well agree with those of experiment.

The relationship to Expected Relative Loss and Cpm by Using Loss Function (손실함수에 의한 기대상대손실과 Cpm의 관련성)

  • 구본철;고수철;김종수
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.41
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    • pp.213-220
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    • 1997
  • Process capability Indices compare the actual performance of manufacturing process to the desired performance. The relationship between the capability index Cpm and the expected squared error loss provides an intuitive interpretation of Cpm. By putting the loss in relative terms a user needs only to specify the target and the distance from the target at which the product would have zero worth, or alternatively, the loss at the specification limits. Confidence limits for the expected relative loss are discussed, and numerical illustration is given.

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Transmission Loss Prediction of KHST's Wall Section (KHST 차량 벽면의 투과손실값 예측)

  • Kim, Kwan-Ju;Yoon, Tae-Jung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.104-109
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    • 2002
  • The purpose of this study is to calculate transmission loss of KHST passenger vehicle's wall section accurately Typical transmission loss measurement of wall in the laboratory condition was carried out in advance, which is easier than KHST. Transmission loss results were compared with those by statistical acoustic method. Transmission loss values of KHST calculated by experimental method are compared with those from closed form solution.

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A Note on the Inter-Loss Time Distribution of an M/G/1/1 Queuing System (M/G/1/1 대기체계의 고객 손실간격 분포에 대한 소고)

  • Lee, Doo Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.41 no.3
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    • pp.37-43
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    • 2016
  • This note discusses the inter-loss time ofan M/G/1/1 queuing system. The inter-loss time is defined as the time duration between two consecutive losses of arriving customers. In this study, we present the explicit Laplace transform of the inter-loss time distribution of an M/G/1/1 queuing system.

Evaluating Predictive Ability of Classification Models with Ordered Multiple Categories

  • Oong-Hyun Sung
    • Communications for Statistical Applications and Methods
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    • v.6 no.2
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    • pp.383-395
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    • 1999
  • This study is concerned with the evaluation of predictive ability of classification models with ordered multiple categories. If categories can be ordered or ranked the spread of misclassification should be considered to evaluate the performance of the classification models using loss rate since the apparent error rate can not measure the spread of misclassification. Since loss rate is known to underestimate the true loss rate the bootstrap method were used to estimate the true loss rate. thus this study suggests the method to evaluate the predictive power of the classification models using loss rate and the bootstrap estimate of the true loss rate.

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Transmission Loss Prediction of KHST′s Wall (KHST 차량 벽면의 투과손실값 예측)

  • Kim, Kwanju;Taejung Yoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.317.2-317
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    • 2002
  • Transmission loss of KHST passenger vehicle was calculated using measured acoustic data: In order to verify the transmission loss results for KHST case, similar experiment was carried out in laboratory condition, which result was compared those by geometric acoustic method. The computational results shows good agreement with the transmission loss magnitude from experiments. This paper also mentions items to obtain more accurate transmission loss values, i. e. how to assure reverberant field condition, the selection of source speaker' location.

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Improved Estimation of Poisson Menas under Balanced Loss Function

  • Chung, Younshik
    • Communications for Statistical Applications and Methods
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    • v.7 no.3
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    • pp.767-772
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    • 2000
  • Zellner(1994) introduced the notion of a balanced loss function in the context of a general liner model to reflect both goodness of fit and precision of estimation. We study the perspective of unifying a variety of results both frequentist and Bayesian from Poisson distributions. We show that frequentist and Bayesian results for balanced loss follow from and also imply related results for quadratic loss functions reflecting only precision of estimation. Several examples are given for Poisson distribution.

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