• Title/Summary/Keyword: Correlation identification

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Mid-upper-arm circumference as a screening measure for identifying children with elevated body mass index: a study for Pakistan

  • Asif, Muhammad;Aslam, Muhammad;Altaf, Saima
    • Clinical and Experimental Pediatrics
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    • v.61 no.1
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    • pp.6-11
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    • 2018
  • Purpose: Mid-upper-arm circumference (MUAC) is considered an alternative screening method for obesity. The aims of this investigation were to examine the ability of MUAC to correctly identify children with elevated body mass index (BMI) and to determine the best MUAC cutoff point for identification of children with high BMI. Methods: Anthropometric measurements (height, weight, and MUAC) from a cross-sectional sample of 7,921 Pakistani children aged 5-14 years were analyzed. Pearson correlation coefficients between MUAC and other anthropometric measurements were calculated. Receiver operating characteristic curve analysis was used to determine the optimal MUAC cutoff point for identifying children with high BMI. Results: Among 7,921 children, the mean (${\pm}$standard deviation) age, BMI, and MUAC were 10.00 (${\pm}2.86years$), 16.16 (${\pm}2.66kg/m^2$), and 17.73 (${\pm}2.59cm$), respectively. The MUAC had a strong positive correlation with BMI. The optimal MUAC cutoff points indicating elevated BMI in boys ranged from 16.76 to 22.73, while the corresponding values in girls ranged from 16.38 to 20.57. Conclusion: MUAC may be used as a simple indicator of overweight/obesity in children, with reasonable accuracy in clinical settings.

Transmitter Detection Technique with Spreading Code Slicing Scheme for AT-DMB System (확산코드 슬라이싱 기술을 이용한 AT-DMB 시스템에서의 송신기 검출 기법)

  • Kim, Yoon-Hyun;Bae, Jung-Nam;Lim, Jong-Soo;Cho, Kyung-Ryong;Cha, Jae-Sang;Kim, Jin-Young
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.6
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    • pp.9-14
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    • 2009
  • In this paper, we proposed spreading code slicing technique for efficient transmitter detection in AT-DMB system with single frequency network. At the transmitter, the spreading code for transmitter identification inserted using slicing technique on forehead of null symbol and then transmitted. In this point, it requires high correlation characteristic spreading code. At the receiver, peak to peak value calculated by correlation process before signal demodulation. The transmitter information by proposed technique is employed to implement the single frequency network (SFN) which is proposed for solving a frequency inefficiency problem of the MFN. The results of the paper can be applied to wireless multimedia digital broadcasting system.

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Model Validation for the CBS Ku-Band Transponder Panel Using Launch Environmental Test (발사환경시험을 이용한 통신방송위성 Ku대역 중계기 패널의 모델 검증)

  • Seo Hyun Suk;Choi Jang Sub;Park Jong Heung;Woo Hyung Je
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.3 s.234
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    • pp.387-394
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    • 2005
  • Accurate predictions and simulations of the behavior of space structures based on analytical models become more important. In order to perform analysis to support the design of Ku-band transponder panel for the Communications and Broadcasting Satellite(CBS), mathematical models of the panel were generated in the form of finite element models. Test verification of these models is required before the transponder panel can be certified for launch environments. A modal identification was performed to obtain modal parameters which can be compared with the test results using correlation techniques. This paper approaches the sensor placement from the standpoint of the structural dynamicist who uses the modal parameter obtained during launch environmental test. The models were validated by performing a test-analysis correlation and updating analysis. It was proved that the Ku-band transponder panel satisfies the environmental test requirements.

Development and Application of High-resolution 3-D Volume PIV System by Cross-Correlation (해상도 3차원 상호상관 Volume PIV 시스템 개발 및 적용)

  • Kim Mi-Young;Choi Jang-Woon;Lee Hyun;Lee Young-Ho
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.507-510
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    • 2002
  • An algorithm of 3-D particle image velocimetry(3D-PIV) was developed for the measurement of 3-D velocity Held of complex flows. The measurement system consists of two or three CCD camera and one RGB image grabber. Flows size is $1500{\times}100{\times}180(mm)$, particle is Nylon12(1mm) and illuminator is Hollogen type lamp(100w). The stereo photogrammetry is adopted for the three dimensional geometrical mesurement of tracer particle. For the stereo-pair matching, the camera parameters should be decide in advance by a camera calibration. Camera parameter calculation equation is collinearity equation. In order to calculate the particle 3-D position based on the stereo photograrnrnetry, the eleven parameters of each camera should be obtained by the calibration of the camera. Epipolar line is used for stereo pair matching. The 3-D position of particle is calculated from the three camera parameters, centers of projection of the three cameras, and photographic coordinates of a particle, which is based on the collinear condition. To find velocity vector used 3-D position data of the first frame and the second frame. To extract error vector applied continuity equation. This study developed of various 3D-PIV animation technique.

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Heat Transfer Correlations for Air-Water Two-Phase Flow of Different Flow Patterns In a Horizontal Pipe

  • Kim, Dongwoo
    • Journal of Mechanical Science and Technology
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    • v.15 no.12
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    • pp.1711-1727
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    • 2001
  • Heat transfer coefficient were measured and new correlations were developed for two-phase heat transfer in a horizontal pipe for different patterns. Flow patterns were observed in a transparent circular pipe (2.54 cm I. D. and L/D=96) using an air/water mixture. Visual identification of the flow patterns was supplemented with photographic data and the results were plotted on the flow regime map proposed by Taitel and Dukler and agreed quite well with each other. A two-phase heat transfer experimental setup was built for this study and a total of 150 two-phase heat transfer data with different flow patterns were obtained under a uniform wall heat flux boundary condition. For these data, the superficial Reynolds number ranged from 640 to 35,500 for the liquid and from 540 to 21,200 for the gas. Our previously developed robust two-phase heat transfer correlation for a vertical pipe with modified constants predicted the horizontal pipe air-water heat transfer experimental data with good accuracy. Overall the proposed correlations predicted the data with a mean deviation of 1.0% and an rms deviation of 12%.

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Real-Time Harmonic Parameters Analyzer for Evaluating Induction Motor Drive System (유도전동기 구동시스템 평가를 위한 실시간 고조피 파라미터 분석장치)

  • Lim, Young-Cheol;Jung, Young-Gook
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.479-483
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    • 1997
  • In general, motor parameters can be divided into mechanical/electrical parameters and harmonic parameters. Mechanical/electrical parameters identification of motor have been studying systematically for a long time. But, systematical study on harmonic parameters analysis for efficient motor drive system are very poor. The goal of this paper is to propose analyzing method of harmonic parameters for motor drive system with various experimental graphic screens and numerical results and to develope harmonic parameters analyzer. A developed analyzer is made up 586-PC and DSP (digital signal processor) board, motor drive system, power and harmonic parameters analyzing software for windows. Harmonic parameters are analyzed using correlation signal processing techniques based on the correlation between voltage and current waveforms. Analysis results are visualized by 3-D current coordinates, and it is compared and evaluated with conventional time/frequency domain. To verify the validity of the proposed system, 1/4HP capacitor run type single phase induction motor and thyristor speed controller is used for analyzing. Harmonic parameters of motor drive system is analyzed and verified, with varying fire angle of thyristor speed controller, and the proposed approach is to confirm validity.

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Design of Multiple Model Fuzzy Predictors using Data Preprocessing and its Application (데이터 전처리를 이용한 다중 모델 퍼지 예측기의 설계 및 응용)

  • Bang, Young-Keun;Lee, Chul-Heui
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.1
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    • pp.173-180
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    • 2009
  • It is difficult to predict non-stationary or chaotic time series which includes the drift and/or the non-linearity as well as uncertainty. To solve it, we propose an effective prediction method which adopts data preprocessing and multiple model TS fuzzy predictors combined with model selection mechanism. In data preprocessing procedure, the candidates of the optimal difference interval are determined based on the correlation analysis, and corresponding difference data sets are generated in order to use them as predictor input instead of the original ones because the difference data can stabilize the statistical characteristics of those time series and better reveals their implicit properties. Then, TS fuzzy predictors are constructed for multiple model bank, where k-means clustering algorithm is used for fuzzy partition of input space, and the least squares method is applied to parameter identification of fuzzy rules. Among the predictors in the model bank, the one which best minimizes the performance index is selected, and it is used for prediction thereafter. Finally, the error compensation procedure based on correlation analysis is added to improve the prediction accuracy. Some computer simulations are performed to verify the effectiveness of the proposed method.

Development of 3-D Volume PIV (3차원 Volume PIV의 개발)

  • Choi, Jang-Woon;Nam, Koo-Man;Lee, Young-Ho;Kim, Mi-Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.6
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    • pp.726-735
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    • 2003
  • A Process of 3-D Particle image velocimetry, called here, as '3-D volume PIV' was developed for the full-field measurement of 3-D complex flows. The present method includes the coordinate transformation from image to camera, calibration of camera by a calibrator based on the collinear equation, stereo matching of particles by the approximation of the epipolar lines, accurate calculation of 3-D particle positions, identification of velocity vectors by 3-D cross-correlation equation, removal of error vectors by a statistical method followed by a continuity equation criterior, and finally 3-D animation as the post processing. In principle, as two frame images only are necessary for the single instantaneous analysis 3-D flow field, more effective vectors are obtainable contrary to the previous multi-frame vector algorithm. An Experimental system was also used for the application of the proposed method. Three analog CCD camera and a Halogen lamp illumination were adopted to capture the wake flow behind a bluff obstacle. Among 200 effective particle s in two consecutive frames, 170 vectors were obtained averagely in the present study.

Depression, Self-efficacy and Coping in Patients with Cancer (암환자의 우울, 자기효능 및 대처간의 상관관계)

  • Ryu, Eun-Jung
    • Korean Journal of Adult Nursing
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    • v.13 no.1
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    • pp.70-81
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    • 2001
  • The relationships among self efficacy, depression and coping with cancer were examined in 194 outpatients who had received a diagnosis of cancer. The sample for this descriptive correlational study consisted of people who were at least 19 years old and had been treated for cancer at 6 hospital in Seoul. Data were collected using a self-report questionnaire. The results of this study are as follows: 1. People who attributed cancer to heredity/family showed the highest mean score of self efficacy. People who attributed cancer to smoking showed the highest mean score of depression. and coping. 2. There were significant differences between causal attribution and depression and between causal attribution and coping. 3. There was a negative correlation between self-efficacy and depression(r=-.301, p= .000), whereas there was a positive correlation between self-efficacy and coping (r=.195, 0=.006). Finally, it is evident that identifying clear perceived causes, self-efficacy, depression and coping in patients with cancer continues to challenge researchers. Based upon this study, it is recommended that future research have a longitudinal design that allows for the identification of changes in perception, emotion and coping and, possibly, different relationships over time.

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Identification of Nursing Activities for Determination of Nursing Cost (간호수가 산정을 위한 간호행위의 규명 연구)

  • 박정호;황보수자;이은숙
    • Journal of Korean Academy of Nursing
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    • v.22 no.2
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    • pp.185-206
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    • 1992
  • In this study nursing activities were examined to determine the nursing cost. A professional nursing group developed a tool for the investigation. 128 nursing activities were identified by the tool in 16 nursing care areas as referenced in the literature. Each activity was examined for four essential factors to define nursing cost ; time consumed for the care, level of professional skill, degree of independency and performer of the care. The activity was rated by a five point Likert scale. This investigation was conducted with the nursing staffing working in the 21 university hospitals in Korea and having more than four years experience especially in medical or surgical wards. The participating nursing staff were screened on the basic of the recommendation of the nursing director. The data were gathered from June 12th to August 12th, 1989. All the data were analyzed for mean, standard deviation, percent, and correlation coefficients between items. The results are summarized as follows : 1. Direct nursing care was classified into 16 large areas and 128 small activities. 2. No significant correlation was found between the study items of each activity. 3. Among 128 nursing activities, Those performed less than 50% of the time by a nurse were excluded from the nursing cost. Also excluded activities which were given less than 9 marks in all three items, time consumed, level of professional skill, and degree of independency. As a result, 83 activities in 14 nursing care areas were selected for the proposal to estimate nursing cost.

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