• Title/Summary/Keyword: Interval Ratio

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An data classification and application of psychophyscial scale (Psychophyscial scale에 의한 자료 분류 및 적용)

  • 곽효연;제종식
    • Journal of the Korea Society of Computer and Information
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    • v.1 no.1
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    • pp.139-146
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    • 1996
  • The estimation technique of psychophysical magnitude Is useful tool which measures to subjective feeling or opinion of human. This paper Introduces properties of the measured data, scales(nominal. ordinal. Interval. and ratio scale). and right analyzing methods of the measured data.

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A case study on misuse of psychophysical scales (Psychophysical Scale 적용시 오류에 관한 사례조사)

  • 곽지영;박성준;한성호
    • Proceedings of the ESK Conference
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    • 1993.10a
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    • pp.133-144
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    • 1993
  • Psychophysical data, in general, belong to one of the four scale categories : Nominal, Ordinal, Interval, and Ratio Scale. This paper introduces properties of the four scale categories and describes some psychophysical scales that attempt to measure subjective feeling or opinion of human. In addition, guidelines of analyzing and interpreting measured data are suggested. Some examples of analyzing and interpreting paychophysical data inappropriately are presented especially with category scales which have been used most widely in measuring subjective information.

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Estimation of Pollutant Loads Delivery Ratio by Flow Duration Using Regression Equation in Hwangryong A Watershed (회귀식을 이용한 황룡A 유역에서의 유황별 유달율 산정)

  • Jung, Jae-Woon;Yoon, Kwang-Sik;Joo, Seuk-Hun;Choi, Woo-Young;Lee, Yong-Woon;Rhew, Doug-Hee;Lee, Su-Woong;Chang, Nam-Ik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.6
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    • pp.25-31
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    • 2009
  • In this study, pollutant loads delivery ratio by flow duration in Hwangryoung A watershed was estimated. The delivery ratio was estimated with measured data by Ministry of Environment(MOE) and the regression equation based on geomorphic parameters. Eight day interval flow data measured by the MOE were converted to daily flow to calculate daily load and flow duration curve by correlating data of neighboring station which has daily flow data. Regression equation developed by previous study was tested to study watershed and found to be satisfactory. The delivery ratios estimated by two methods were compared. For the case of Biochemical oxygen demand(BOD), the delivery ratios of low flow condition were 7.6 and 15.5% by measured and regression equation, respectively. Also, the delivery ratios of Total phosphorus(T-P) for normal flow condition were 13.3 and 6.3% by measured and regression equation, respectively.

Torque Ripple Reduction of Interior Permanent-Magnet Synchronous Motors Driven by Torque Predictive Control (토크예측제어를 이용한 매입형 영구자석 동기전동기의 토크리플저감기법)

  • Kim, Hyunseob;Han, Jungho;Song, Joong-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.2
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    • pp.102-109
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    • 2013
  • In this paper, a new torque predictive control method of interior permanent magnet synchronous motor is developed based on an extended rotor flux. Also, a duty ratio prediction method is proposed and allows the duty ratio of the active stator voltage vector to be continuously calculated. The proposed method makes it possible to relatively reduce the torque ripple under the steady state as well as to remain the good dynamic response in the transient state. With the duty ratio prediction method, the magnitude and time interval of the active stator voltage vector applied can be continuously controlled against the varying operation conditions. This paper shows a comparative study among the switching table direct torque control(DTC), the SVM-DTC, conventional torque predictive control, and the proposed torque predictive control. Simulation results show validity and effectiveness of this work.

Relationship between Blood Alcohol Concentrations and Breath Alcohol Concentrations of Healthy Korean Males (혈중 알코올 농도와 호흡기 알코올 농도 상관성: 한국인 남성)

  • Yi, SeungHwan;Nam, BeomWoo;Seo, JeongSeok
    • Journal of Auto-vehicle Safety Association
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    • v.7 no.4
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    • pp.9-15
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    • 2015
  • The relationship between BAC(Blood Alcohol Concentrations) and BrACs(Breath Alcohol Concentrations) and also partition ratio of healthy Korean adult males (96 males) are researched in this paper and its dependency is described according to TBW (total body water), BMI (body mass index), BFM (body fat mass), and PBF (percentage of body fat). Among the above four variables, TBW affects significantly to the partition ratio compared to the other variables. The partition ratio of Korean healthy males showed 1,913 (95 % Confidence Interval (C.I.) from 1,889 to 1,937) for the whole time intervals. However, when Q was averaged after 60 minutes later, its values was 2,011 (95 % C.I. from 1,982 to 2,040). Bland-Altman plots showed the compatibility of measurement methods of multi-gas analyzer, and the biases according to the partition ratios (Q=2,100 and Q=1,913) gave -0.0052 % (95 % CI from -0.0059 to -0.0045%) and -0.0004 % (95 % CI from -0.0011 to +0.0003%), respectively.

Abdominal Obesity as a Risk Factor of Ischemic Stroke in Case-control study (복부비만과 허혈성 뇌졸중)

  • Yim, Hee-Sun;Ko, Seong-Gyu
    • Journal of Korean Medicine for Obesity Research
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    • v.2 no.1
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    • pp.25-36
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    • 2002
  • Objective: The purposes of this study are to know the relations of abdominal obesity and ischemic stroke and to know what index could represent the abdominal obesity appropriately. Methods. We have done case-control study and recruited 97 ischemic stroke patients and 117 controls. Case is matched by control by individual matching. All participants had questionnaire, interview and then were examined waist-hip ratio, waist circumference and body mass index. Results : WC, WHR and Hypertension history had differences in two groups, case and control groups. But BMI and other factors weren't significant. According to Quartile of Waist Circumference, the two groups had the differences in hypertension history, diabetes history, smoking status, WHR, BMI, and weight and in the Quartile of Waist-Hip Ratio Quartile, past history of hypertension and diabetes, WC, BMI and weight had the significances. Sex, Age Adjusted and Multivariate Odds Ratio (95% Confidence Interval) of WC Quartile are 2.083, 1.628, 4.491 and 4.418, 4.964, 12.306, and in WHR, the Ors are 2.252, 5.743, 15.776 and 2.632, 8.918, 23.596. Conclusions: We knew from these results that abdominal obesity is very important risk factor of ischemic stroke and WHR more than WC is a good indicator of abdominal obesity, so we should reduce the WHR to prevent of ischemic stroke.

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Error Accumulation and Transfer Effects of the Retrieved Aerosol Backscattering Coefficient Caused by Lidar Ratios

  • Liu, Houtong;Wang, Zhenzhu;Zhao, Jianxin;Ma, Jianjun
    • Current Optics and Photonics
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    • v.2 no.2
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    • pp.119-124
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    • 2018
  • The errors in retrieved aerosol backscattering coefficients due to different lidar ratios are analyzed quantitatively in this paper. The actual calculation shows that the inversion error of the aerosol backscattering coefficients using the Fernald backward-integration method increases with increasing inversion distance. The greater the error in the lidar ratio, the faster the error in the aerosol backscattering coefficient increases. For the same error in lidar ratio, the smaller actual aerosol backscattering coefficient will get the larger relative error of the retrieved aerosol backscattering coefficient. The errors in the lidar ratios for dust or the cirrus layer have great impact on the retrievals of backscattering coefficients. The interval between the retrieved height and the reference range is one of the important factors for the derived error in the aerosol backscattering coefficient, which is revealed quantitatively for the first time in this paper. The conclusions of this article can provide a basis for error estimation in retrieved backscattering coefficients of background aerosols, dust and cirrus layer. The errors in the lidar ratio of an aerosol layer influence the retrievals of backscattering coefficients for the aerosol layer below it.

Stability study on tenon-connected SHS and CFST columns in modular construction

  • Chen, Yisu;Hou, Chao;Peng, Jiahao
    • Steel and Composite Structures
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    • v.30 no.2
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    • pp.185-199
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    • 2019
  • Modular construction is an emerging technology to accommodate the increasing restrictions in terms of construction period, energy efficiency and environmental impacts, since each structural module is prefabricated offsite beforehand and assembled onsite using industrialized techniques. However, some innate structural drawbacks of this innovative method are also distinct, such as connection tying inaccessibility, column instability and system robustness. This study aims to explore the theoretical and numerical stability analysis of a tenon-connected square hollow section (SHS) steel column to address the tying and stability issue in modular construction. Due to the excellent performance of composite structures in fire resistance and buckling prevention, concrete-filled steel tube (CFST) columns are also taken into account in the analysis to evaluate the feasibility of adopting composite sections in modular buildings. Characteristic equations with three variables, i.e., the length ratio, the bending stiffness ratio and the rotational stiffness ratio, are generated from the fourth-order governing differential equations. The rotational stiffness ratio is recognized as the most significant factor, with interval analysis conducted for its mechanical significance and domain. Numerical analysis using ABAQUS is conducted for validation of characteristic equations. Recommendations and instructions in predicting the buckling performance of both SHS and CFST columns are then proposed.

Correlation Results of Pulse/Respiration Ratio and Body Composition Analysis (맥솔(脈率)과 체성분(體成分) 분석(分析)의 상관성(相關性) 연구(硏究))

  • Park, Jae-Sung;Park, Young-Bae;Kim, Min-Yong;Park, Young-Jae
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.10 no.2
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    • pp.132-150
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    • 2006
  • Objectives : The objective is that we measure and analyze Pulse-Respiration Ratio and Body Composition Analysis to study the correlation between both. Methods : First, after subjects take a rest over 10 minutes, we measure their electrocardiogram and respiration pattern through which we take average peak interval to calculate an average pulse cycle and a respiration cycle. An average respiration cycle divided by an average Pulse Rate gives Pulse-Respiration Ratio. Next, we draw out 22 Body Composition Analysis indicators by using In-Body 720 model. Last, we analyze and take statistics on them by using SPSS 13.0 program. Results : Negative is the correlation between P/R Ratio and Body Composition Analysis indicator like fatness degree, body fat volume, body fat rate, abdominal fatness, BMI. Conclusions : 1. The higher P/R Ratio the more likely to be thin, the lower P/R Ratio the more likely to be fat. 2. We separately analyze P/R Ratio depending on each breathing frequency and pulse frequency to find out that breathing frequency has great influence and that breathing frequency decides the fatness degree. 3. In study on the correlation between P/R Ratio and Body Composition Analysis, fatness degree, in-body fat volume, in-body fat rate, BMI are the related indicators, which shows the connection with the fatness indicators. 4. In study on the correlation between Han-Yeol [寒熱] grade and Body Composition Analysis indicators, the result is that Han[寒] has no connection and that only Yeol[熱] grade has something to do with it, which means the higher heat symptom subjects have, the more basic metabolism volume and muscular build they have.

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Availability of Blood Urea Nitrogen/Creatinine Ratio in Gastrointestinal Bleeding with Melena in Children

  • Kim, Kyu Seon;Kang, Chan Ho;Kim, Jae Young
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.18 no.1
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    • pp.30-38
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    • 2015
  • Purpose: The aims of our study were to evaluate the blood urea nitrogen to creatinine ratio (BUN/Cr ratio) for distinguishing between an upper and lower gastrointestinal bleeding (GIB), and differentiating between the two most common causes of upper gastrointestinal bleeding (UGIB) presenting with melena in children. Methods: Retrospective data of patients with GIB presenting with melena were analyzed. The data from 60 cases were reviewed including demographics, laboratory findings, diagnostic modalities and results, treatments, and transfusions. Results: Among the 60 cases, UGIB and lower gastrointestinal bleeding (LGIB) were found in 35 cases (58.3%) and 14 cases (23.3%), respectively. The two common causes of UGIB were varices (37.1%), and peptic ulcer diseases (PUD) (31.4%). The BUN/Cr ratio of 30 or greater was higher in UGIB than LGIB (odds ratio [OR], 6.9; 95% confidence interval [95% CI], 1.3-37.2). In UGIB, the BUN/Cr ratio of the varices group was higher than that of the PUD group (p=0.015). The OR for the BUN/Cr ratio appeared as 1.2 per unit increase in the varices group than the PUD group (95% CI, 1.03-1.3). There was no difference between the PUD group and Meckel's diverticulum group. Conclusion: The BUN/Cr ratio was not uneven in differentiating UGIB from LGIB of children with melena in our study. This suggests that BUN/Cr ratio should be interpreted carefully.