• Title/Summary/Keyword: variance ratio

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The Effects of Bag Weight and Carrying Bag Position on Vastus Medialis Oblique and Vastus Lateralis Muscle Activity Ratio during Step up in Healthy Adult (계단오르기 동안 가방의 무게와 가방메기 형태가 안쪽빗넓은근과 가쪽넓은근의 근활성도비에 미치는 영향)

  • Cho, Hyunrae
    • Journal of The Korean Society of Integrative Medicine
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    • v.2 no.3
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    • pp.49-55
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    • 2014
  • Purpose : The purpose of this study was to investigate the effect of cross bag weight and carrying bag position type on vastus medialis oblique and vastus lateralis muscle activity ratio during step up. Method : Twenty healthy subjects participated in this study. subjects randomized performed step up with bag weight less than 15%, more than 15% of totalbody weight and without bag and carrying bag position ipsilateral and contralateral. muscle activity was measured with surface electromyography. One-way analysis of variance with repeated measures was used with a significance level of 0.05 Result : The results of this study were as follows: 1. The muscle activity ratio decreased significantly ipsilateral bag position more than 15% of body weight(p<.05). Also, the muscle activity ratio increased significantly contra lateral bag position more than 15% of body weight(p<.05). Conclusion : In conclusion, it was found that applied carrying bag position with weight on VMO,VL muscle activity ratio during step up down. Therefore carrying bag position can be used to selective activate vastus medialis oblique muscle in subjects with patellofemoral pain syndrome.

Fuel properties of biodiesel produced from beef-tallow and corn oil blends based on the variation in the fatty acid methyl ester composition

  • Woo, Duk Gam;Kim, Tae Han
    • Korean Journal of Agricultural Science
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    • v.46 no.4
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    • pp.941-953
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    • 2019
  • Biodiesels are being explored as a clean energy alternative to regular diesel, which causes pollution. In this study, the optimum conditions for producing biodiesel (BD) by combining beef tallow, an animal waste resource with a high saturated fatty acid content, and corn oil, a vegetable oil with a high unsaturated fatty acid content, were investigated, and the fuel properties were analyzed. Furthermore, Multivariate Analysis of Variance (MANOVA) was used to verify the optimum conditions for producing biodiesel. The influences of control factors, such as the oil blend ratio and methanol to oil molar ratio, on the fatty acid methyl ester and biodiesel production yield were investigated. As a result, the optimum condition for producing blended biodiesel was verified to be tallow to corn oil blend ratio of 7 : 3 (TACO7) and a methanol to oil molar ratio of 14 : 1. Moreover, the interaction between the oil blend ratio and the methanol to oil molar ratio has the most crucial effects on the production of oil blended biodiesel. In conclusion, the analysis results of the fuel properties of TACO7 BD satisfied the BD quality standard, and thus, the viability of BD blended with waste tallow as fuel was verified.

Motion Estimation Algorithm Using Variance and Adaptive Search Range for Frame Rate Up-Conversion (프레임 율 향상을 위한 분산 및 적응적 탐색영역을 이용한 움직임 추정 알고리듬)

  • Yu, Songhyun;Jeong, Jechang
    • Journal of Broadcast Engineering
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    • v.23 no.1
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    • pp.138-145
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    • 2018
  • In this paper, we propose a new motion estimation algorithm for frame rate up-conversion. The proposed algorithm uses the variance of errors in addition to SAD in motion estimation to find more accurate motion vectors. Then, it decides which motion vectors are wrong using the variance of neighbor motion vectors and the variance between current motion vector and neighbor's average motion vector. Next, incorrect motion vectors are corrected by weighted sum of eight neighbor motion vectors. Additionally, we propose adaptive search range algorithm, so we can find more accurate motion vectors and reduce computational complexity at the same time. As a result, proposed algorithm improves the average peak signal-to-noise ratio and structural similarity up to 1.44 dB and 0.129, respectively, compared with previous algorithms.

Estimation of Genetic Parameters of Body Weight Traits in Ghezel Sheep

  • Baneh, Hasan;Hafezian, Seyed Hasan;Rashidi, Amir;Gholizadeh, Mohsen;Rahimi, Ghodrat
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.2
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    • pp.149-153
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    • 2010
  • The present study was carried out to estimate genetic parameters for body weight traits in Ghezel sheep. The data set used was records of 9,221 lambs from 180 sires and 5,060 dams for birth weight (BW), 7,206 lambs from 167 sires and 4,497 dams for weaning weight (WW) and 6,112 lambs from 157 sires and 3,841 dams for 6-months weight (6 MW), which were collected from 1999 to 2007 (9-years) at Ghezel sheep Breeding Station in west Azarbaijan. Variance components and corresponding genetic parameters were obtained with univariate analyses fitting animal models using restricted maximum likelihood (REML) methods. The most suitable model for each trait was determined based on log likelihood ratio tests. Birth year, lamb gender, type of birth, age of dam and herd were significant sources of variation on BW, WW and 6 MW (p<0.01). Direct estimate of heritability for BW, WW and 6 MW was 0.24, 0.29 and 0.37, respectively. The estimate of maternal permanent environmental variance as a proportion of phenotypic variance was 0.09 and 0.05 for BW and WW, respectively. The results of this study showed that genetic progress for growth traits is possible by selection.

Variance Mismatched Quantization of a Generalized Gamma Source (일반화된 감마 신호원의 분산 불일치된 양치화)

  • 구기일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.10A
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    • pp.1566-1575
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    • 2000
  • This paper studies mismatched scalar quantization of a generalized gamma source by a quantizer that is optimally (in the mean square error sense) designed for another generalized gamma source. Specifically, it considers variance-mismatched quantization which occurs when the variance of the source to be quantized differs from tat of the designed-for source. The main result is the two distortion formulas derived from Bennett's integral. The first formula is an approximation expression that uses the outermost threshold of an optimum scalar quantizer, and the second formula, in turn, uses an approximation formula for this outermost threshold. Numerical results are obtained for Laplacian sources, which are example of a generalized gamma source, and comparisons are made between actual mismatched distortions and the two formulas. These numerical results show that the two formulas become more accurate, as the number of quantization points gets larger and the ratio of the source variance to that of the designed-for source gets bigger. For example, the formulas are within 2~4% of the actual distortion for approximately 64 quantization points or more. In conclusion, the proposed approximation formulas are considered to have contribution as closed formulas and for their accuracy.

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Voice Activity Detection based on Adaptive Band-Partitioning using the Likelihood Ratio (우도비를 이용한 적응 밴드 분할 기반의 음성 검출기)

  • Kim, Sang-Kyun;Shim, Hyeon-Min;Lee, Sangmin
    • Journal of Korea Multimedia Society
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    • v.17 no.9
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    • pp.1064-1069
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    • 2014
  • In this paper, we propose a novel approach to improve the performance of a voice activity detection(VAD) which is based on the adaptive band-partitioning with the likelihood ratio(LR). The previous method based on the adaptive band-partitioning use the weights that are derived from the variance of the spectral. In our VAD algorithm, the weights are derived from LR, and then the weights are incorporated with the entropy. The proposed algorithm discriminates the voice activity by comparing the weighted entropy with the adaptive threshold. Experimental results show that the proposed algorithm yields better results compared to the conventional VAD algorithms. Especially, the proposed algorithm shows superior improvement in non-stationary noise environments.

Multivariate Classification of Choson Coins (다변수 분석법에 의한 조선시대 동전의 분류연구)

  • Lee, Chang-Keun;Kang, Hyung-Tai;Goh, Sung-Hee
    • 보존과학연구
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    • s.8
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    • pp.1-12
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    • 1987
  • Fifty ancient Korean coins originated in Choson dynasty have been determined for 9 elements such as Sn, Fe, As, Ag, Co, Sb, Ir, Ru and Ni by instrumental neutron activation analysis and for 3 elements such as Cu, Pb, and Zn by atomicalsorption spectrometry. Bronze coins originated in early days of the dynasty contain as major constituents Cu, Pb and Sn approximately in the ratio 90 : 4 : 3, where as, those in latter days contain in the ratio 7 : 2 : 0. Brass coins which had begun in 17century contain as major constituents Cu, Zn and Pb approximately in the ratio 7 : 1: 1. The multivariate date have been analyzed for the relation among elemental contents through the variance-covariance matrix. The data have been fur theranalyzed by a principal component mapping method. As the results training set of 8class have been chosen, based on the spread of sample points in an eigenvector plotand archaeolgical data such as age and the office of minting.

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Shape Optimization of A Micromixer with Herringbone Grooves Using Kriging Model (헤링본 미세혼합기의 크리깅 모델을 사용한 최적형상설계)

  • Ansari, Mubashshir Ahmad;Kim, Kwang-Yong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.8
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    • pp.711-717
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    • 2007
  • Shape optimization of a staggered herringbone groove micromixer using three-dimensional Navier-Stokes analysis has been carried using Kriging model. The analysis of the degree of mixing is performed by the calculation of spatial data statistics. The calculation of the variance of the mass fraction at various nodes on a plane in the channel is used to quantify mixing. A numerical optimization technique with Kriging model is applied to optimize the shape of the grooves on a single wall of the channel. Three design variables, namely, the ratio of groove width to groove pitch, the ratio of the groove depth to channel height ratio and the angle of the groove, are selected for optimization. A mixing index is used as the objective function. The results of the optimization show that the mixing is very sensitive to the shape of the groove which can be used in controlling mixing in microdevices.

Estimation of Gauge R&R by Variance Components of Measurement ANOVA (측정 ANOVA의 분산성분에 의한 게이지 R&R 추정)

  • Choi, Sung-woon
    • Journal of the Korea Safety Management & Science
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    • v.12 no.1
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    • pp.199-205
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    • 2010
  • The research proposes the three-factor random measurement models for estimating the precision about operator, part, tool, and various measurement environments. The combined model with crossed and nested factors is developed to analyze the approximate F test by degrees of freedom given by Satterthwaite and point estimation of precisions from expected mean square. The model developed in this paper can be extended to the three useful models according to the type of nested designs. The study also provides the three-step procedures to evaluate the measurement precisions using three indexes such as SNR(Signal-To-Noise Ratio), R&R TR(Reproducibility&Repeatability-To-Total Precision Ratio), and PTR(Precision-To-Tolerance Ratio), The procedures include the identification of resolution, the improvement of R&R reduction, and the evaluation of precision effect.

A Comparison of C/No Estimation Techniques for Commercial GPS Receivers under Jamming Environments (전파방해환경에서 상용 GPS 수신기의 C/No 추정기법 성능분석)

  • Baek, Jeehyeon;Yoo, Seungsoo;Kim, Sun Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.11
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    • pp.973-975
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    • 2013
  • In this paper, the carrier-to-noise power ratio estimation performances for commercial GPS receiver are shown by simulation and are analyzed under weak signal reception, high sensitivity signal reception, and the matched spectrum jamming signal reception environments.