• Title/Summary/Keyword: Sum of Square

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Sleep Patterns and Factors Associated with Excessive Daytime Sleepiness in University Students (대학생의 수면양상과 주간졸음증에 영향을 미치는 요인)

  • Yi, Hyeryeon;Shin, Mee-Kyung;Won, Jongsoon
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.19 no.4
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    • pp.425-433
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    • 2012
  • Purpose: The purpose of this study was to investigate sleep patterns and predictors of excessive daytime sleepiness (EDS) in university students. Methods: Participants were 120 university students who were attending two universities in S-city and C-city. Data were collected from May 20 to June 15, 2012 using self-report questionnaires which included Johns' Epworth Sleepiness Scale, Yi's Sleep Quality Scale, and Beck Depression Inventory. Data were digitalized and analyzed using frequency, percentages, means and standard deviations, Wilcoxon rank sum test, Chi-square test, Fisher's exact test, and multiple logistic regression with SAS 9.0. Results: Mean total sleep time was 6.6 hours on weekdays, 8.1 hours on weekends. Mean sleep latency was 19.1 minutes and the score for mean sleep quality was 22.6. Prevalence of EDS was 12.5%. Depression was significantly different between EDS and Non-EDS students (t=2.17, p=.030). Multiple logistic regression showed that the only factor associated with EDS was depression (adjusted odds ratio of depression=5.33, 95% Confidence Interval=1.49-19.04). Conclusion: Results of this study indicate that university students experience short sleep time, low sleep quality, and common EDS with depression, suggesting that students with complaints of EDS should be completely assessed for depression as well as sleep problems.

Uncertainty Evaluation of the Estimated Release Rate for the Atmospheric Pollutant Using Monte Carlo Method (Monte Carlo 방법을 이용한 대기오염 배출률 예측의 불확실성 평가)

  • Jeong, Hyo-Joon;Kim, Eun-Han;Suh, Kyung-Suk;Hwang, Won-Tae;Han, Moon-Hee
    • Journal of Environmental Science International
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    • v.15 no.4
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    • pp.319-324
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    • 2006
  • Release rate is one of the important items for the environmental impact assessment caused by radioactive materials in case of an accidental release from the nuclear facilities. In this study, the uncertainty of the estimated release rate is evaluated using Monte Carlo method. Gaussian plume model and linear programming are used for estimating the release rate of a source material. Tracer experiment is performed at the Yeoung-Kwang nuclear site to understand the dispersion characteristics. The optimized release rate was 1.56 times rather than the released source as a result of the linear programming to minimize the sum of square errors between the observed concentrations of the experiment and the calculated ones using Gaussian plume model. In the mean time, 95% confidence interval of the estimated release rate was from 1.41 to 2.53 times compared with the released rate as a result of the Monte Carlo simulation considering input variations of the Gaussian plume model. We confirm that this kind of the uncertainty evaluation for the source rate can support decision making appropriately in case of the radiological emergencies.

A Comparative Study on the Effects on Urinary Incontinence between Pelvic Floor Muscle Exercise and Magnetic Stimulation Therapy (지역사회 요실금 여성의 골반저근운동과 자기장자극 효과비교)

  • Cho, Myung-Sook;Kang, Hae-Young
    • Research in Community and Public Health Nursing
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    • v.19 no.4
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    • pp.696-703
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    • 2008
  • Purpose: To Perform a randomized comparative study investigating the effects of Pelvic Floor Muscle Exercise(PME) and Magnetic Stimulation Therapy(MST) and to identified the problems in each of PME & MST Method: Forty-nine patients with mild stress incontinence were randomly assigned to either of two treatment groups (24 patients in the PME group and 25 in the MST group). The PME group had a video exercising program for 40 times every day during 6 weeks. The MST group was treated with BioCon-2000TM, 2times/ week for six weeks. Pre-test and post-test were performed by Prineometer, 1-hour pad test. and Jackson's BFLUTS questionnaire of Jackson. Collected data were analysed using SAS 9.1 by frequency, Kolmogorov-Smirnov Z. Chi Square-test, t-test, Fisher Exact probability test, Paired t-test, and Wilcoxon's rank sum test. Results: In comparison between before and after PME and MST, statistically significant difference was observed in maximal vaginal pressure, duration of vaginal contraction, amount of urine, and symptom of urination. In the comparison of the effectiveness between PME & MST, only the maximal of vaginal pressure (Z=2.58, p= .010) was significantly different. Conclusion: The factor more effective in the MST group than in the PME group was high compliance.

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Combined effect of the horizontal components of earthquakes for moment resisting steel frames

  • Reyes-Salazar, Alfredo;Juarez-Duarte, Jose A.;Lopez-Barraza, Arturo;Velazquez-Dimas, Juan I.
    • Steel and Composite Structures
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    • v.4 no.3
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    • pp.189-209
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    • 2004
  • The commonly used seismic design procedures to evaluate the maximum effect of both horizontal components of earthquakes, namely, the Square Root of the Sum of the Squares (SRSS) and the 30-percent (30%) combination rules, are re-evaluated. The maximum seismic responses of four three-dimensional moment resisting steel frames, in terms of the total base shear and the axial loads at interior, lateral and corner columns, are estimated as realistically as possible by simultaneously applying both horizontal components. Then, the abovementioned combination rules and others are evaluated. The numerical study indicates that both, the SRSS rule and the 30% combination method, may underestimate the combined effect. It is observed that the underestimation is more for the SRSS than for the 30% rule. In addition, the underestimation is more for inelastic analysis than for elastic analysis. The underestimation cannot be correlated with the height of the frames or the predominant period of the earthquakes. A basic probabilistic study is performed in order to estimate the accuracy of the 30% rule in the evaluation of the combined effect. Based on the results obtained in this study, it is concluded that the design requirements for the combined effect of the horizontal components, as outlined in some code-specified seismic design procedures, need to be modified. New combination ways are suggested.

Lower Body Somatotype Classification and Discrimination of Elderly Women According to Index (지수치를 이용한 노년 여성의 하반신 체형 유형화에 관한 연구)

  • 김수아;이경미;최혜선
    • Journal of the Korean Society of Costume
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    • v.53 no.6
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    • pp.117-130
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    • 2003
  • The purpose of this study is to provide the basic data on the development of ready-to-wear clothing for the elderly women as the population of the elderly has been constantly increasing as well as the purchasing power of the aged. The body measurements of 318 elderly women were taken. whose ages were over 60 years and enrolled in colleges for the elderly. sports centers. or business sites in Seoul and the neighboring districts. A total of 39 features in the lower body were used for the anthropometric measurement and analysis. The results of the study are as follows: 1. Indices of height and weight were used for factor analysis. cluster analysis, and discriminant analysis in order to 'classify lower body somatotype according to shape, excluding size factors. From the results of the factor analysis. the 5 factors showed the cumulative sum of square at 75.63%. 2. Somatotype were classified into two types according to a cluster analysis using height and weight dices. Type 1 is the group is relatively tall and has somewhat fat lower limbs. Type 2 is considered fat and has obesity factors around waist and abdomen area. The hit rate for the classified two groups showed the result at 95.9%.

Internal evaluation of provisional restorations according to the dental CAD/CAM manufacturing method : Three-dimensional superimpositional analysis (치과 CAD/CAM 가공방식에 따른 임시보철물의 내면 적합도 : 3차원 중첩 분석)

  • Kim, Jae-Hong;Kim, Ki-Baek
    • Journal of Technologic Dentistry
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    • v.41 no.2
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    • pp.81-86
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    • 2019
  • Purpose: The purpose of the present study was to compare the internal fit of two different temporary restorations fabricated by dental CAD/CAM system and to evaluate clinical effectiveness. Methods: Composite resin tooth of the maxillary first molar was prepared as occlusal reduction(2.0mm), axial reduction(1mm offset), vertical angle(6 degree) and chamfer margin for a temporary crown and duplicated epoxy die was fabricated. The epoxy dies were used to fabricate provisional restorations by CAD/CAM milling technique or 3D-printing technique. The inner data from all crowns were superimposed on the master die file in the 'best-fit alignment' method using 3D analysis software. Statistical analysis was performed using a Wilcoxon's rank sum test for differences between groups. Results: It showed that the internal RMS(Root Mean Square) values of the additive group were significantly larger than those of other group. No significant differences in internal discrepancies were observed in the temporary crowns among the 2 groups with different manufacturing method. Conclusion: All the groups had the internal fit within the clinical acceptable range (< $50{\mu}m$). The continuous research in the future to be applied clinically for the adaptation of additive manufacturing technique are needed.

A Study on Comparison of Combination Rules for the Seismic Analysis on Curved Bridges with the Different Radiuses of Curvature (곡선교의 내진 해석 시 곡률에 따른 하중 조합 방법의 비교에 관한 연구)

  • Ryu, Dong-Hyeon;Shin, Myoung-Gyu;Park, Jin-Wan;Kim, Moon-Kyum
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.567-572
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    • 2008
  • This paper's purpose is to improve determining of the critical response of curved bridge to multi-component seismic motion. There are several methods to combine responses by multi-component excitation response, 30%, 40% rules and square-root-of-sum (SRSS). These combination rules determine same value of critical response in straight bridges. However, each method has critical response value of different magnitude in curved bridges. Thus a study about critical response of curved bridges is required. This paper presents comparison critical responses value as each combination rule, 30%, 40% rules and SRSS on curved bridges with the different radiuses of curvature. This study was carried out by response spectrum analysis of OO IC steel box girder bridge using SAP2000. It is concluded as follows: 1) In curved bridges, 30% and 40% rules tend to underestimate the critical response relatively to SRSS. 2) When bridges have smaller radiuses than 100m, difference between SRSS and 30% or 40% rules let run errors up as radiuses of curvature decreased.

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Interpretation of Genotype × Environment Interaction of Sesame Yield Using GGE Biplot Analysis

  • Shim, Kang-Bo;Shin, Seong-Hyu;Shon, Ji-Young;Kang, Shin-Gu;Yang, Woon-Ho;Heu, Sung-Gi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.60 no.3
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    • pp.349-354
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    • 2015
  • The AMMI (additive main effects and multiplicative interaction) and GGE (genotype main effect and genotype by environment interaction) biplot which were accounted for a substantial part of total sum of square in the analysis of variance suggested to be more appropriate models for explaining G $\times$ E interaction. The grain yield of total ten sesame genotypes was significantly affected by environment which explained 61% of total variation, whereas genotype and genotype x environment interaction (G $\times$ E) were explained 16%, 24% respectively. From the results of experiment, three genotypes Miryang49, Koppoom and Ansan were unstable, whereas other three genotypes Kyeongbuk18, Miryang50 and Kanghuk which were shorter projections to AEA ordinate were relatively stable over the environments. Yangbak which was closeness to the mean yield and short projection of the genotype marker lines was regarded as genotype indicating good performance with stability. Ansan, Miryang48 and Yangbaek showed the best performance in the environments of Naju, Suwon, Iksan and Andong. Similarly, genotype Miyrang47 exhibited the best performance in the environments of Chuncheon and Miryang. Andong is the closest to the ideal environment, and therefore, is the most desirable among eight environments.

Creep of Drift Pin Moment Resisting Joint of LVL under Changing RH (상대습도 변동하의 휨 모멘트가 작용하는 단판적층재 Drift Pin 접합부의 크리프 변형 거동)

  • 홍순일
    • Journal of Korea Foresty Energy
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    • v.18 no.2
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    • pp.84-91
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    • 1999
  • The objective of this study was to present creep and the effects of mechano-sorptive deflection of drift pin moment resisting joint between LVL members under changing relative humidity (RH) conditions. The LVL members with steel gusset were jointed by a square pattern of eight injected drift pin. Three diameter drift pins were used to test specimens (6mm, 10mm, and 16mm). The creep test was conducted under two constant loading conditions : one at 30 kgf(840 kgf-cm) and the other at 60 kgf(1680 kgf-cm). The experiment was conducted in an open shed outside. (1)The total rotation creep model of moment resisting joing can be expressed as the sum of the creep of controlled environment (3-parameter model), dimensional change and mechano-sorptive deflection resulting from the variable environment. (2)Mechanosorptive rotation creep is recoverable as moisture content increases during adsorption. Least squares method for linear regression analysis was performed using mechano-sorptive rotation creep as the dependent variable and moisture content as the independent variable. The slope of low moment specimens are compared with those of high moment. This means that low moment condition is more easily affected by changes in humidity than high moment conditions. (3)Although creep deflection is higher for small diameter drift pin than for large diameter drift pin, the shape of creep deflection curves for all specimens is similar.

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Individual Channel Estimation Based on Blind Interference Cancellation for Two-Way MIMO Relay Networks

  • He, Xianwen;Dou, Gaoqi;Gao, Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.8
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    • pp.3589-3605
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    • 2018
  • In this paper, we investigate an individual channel estimation problem for multiple-input multiple-output (MIMO) two-way amplify-and-forward (AF) relay networks. To avoid self-interference during the estimation of the individual MIMO channels, a novel blind interference cancellation (BIC) approach is proposed based on an orthogonal preceding framework, where a pair of orthogonal precoding matrices is utilized at the source nodes. By designing an optimal decoding scheme, we propose to decompose the bidirectional transmission into a pair of unidirectional transmissions. Unlike most existing approaches, we make the practical assumption that the nonreciprocal MIMO channel and the mutual interference of multiple antennas are both taken into consideration. Under the precoding framework, we employ an orthogonal superimposed training strategy to obtain the individual MIMO channels. However, the AF strategy causes the noise at the terminal to be the sum of the local noise and the relay-propagated noise. To remove the relay-propagated noise during the estimation of the second-hop channel, a partial noise-nulling method is designed. We also derive a closed-form expression for the total mean square error (MSE) of the MIMO channel from which we compute the optimal power allocation. The simulation results demonstrate that the analytical and simulated curves match fully.