• Tunnel and Underground Space
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• v.5 no.2
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• pp.89-94
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• 1995

Regression analysis and a comparative study were carried out for 52 blast vibration data which were monitored by changing the monitoring distance and charge per delay. The results are as follows: 1) The square and cube root scalings and general equation which have a confidence level at the point of 90% and 99% are V90=33300(SD)-2.026 , V90=23600(SD)-1.993, V90=26300W0.755 R-2.007 and V99=48400(SD)-2.026, V99=34000(SD)-1.993 , V99=38100W0.755R-2.007, respectively. 2) There is need to decide the allowable max. charge weight per delay considering the cross points comparatively of the nomogram constructed using several predictived equations. 3) It is necessary to derive the predictive equation on the basis of blast vibration level monitored in field and to decide safe vibration level and the confidence level.

• Nuclear Engineering and Technology
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• v.35 no.5
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• pp.399-411
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• 2003

A model predictive control method is applied to design an automatic controller for thermal power control in a reactor core. The basic concept of the model predictive control is to solve an optimization problem for a finite future at current time and to implement as the current control input only the first optimal control input among the solutions of the finite time steps. At the next time step, the second optimal control input is not implemented and the procedure to solve the optimization problem is then repeated. The objectives of the proposed model predictive controller are to minimize the difference between the output and the desired output and the variation of the control rod position. The nonlinear PWR plant model (a nonlinear point kinetics equation with six delayed neutron groups and the lumped thermal-hydraulic balance equations) is used to verify the proposed controller of reactor power. And a controller design model used for designing the model predictive controller is obtained by applying a parameter estimation algorithm at an initial stage. From results of numerical simulation to check the controllability of the proposed controller at the $5\%/min$ ramp increase or decrease of a desired load and its $10\%$ step increase or decrease which are design requirements, the performances of this controller are proved to be excellent.

• Nutrition Research and Practice
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• v.15 no.1
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• pp.95-105
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• 2021

BACKGROUND/OBJECTIVES: The measurement of body composition, including muscle and fat mass, remains challenging in large epidemiological studies due to time constraint and cost when using accurate modalities. Therefore, this study aimed to develop and validate prediction equations according to sex to measure lean body mass (LBM), appendicular skeletal muscle mass (ASM), and body fat mass (BFM) using anthropometric measurement, serum creatinine level, and lifestyle factors as independent variables and dual-energy X-ray absorptiometry as the reference method. SUBJECTS/METHODS: A sample of the Korean general adult population (men: 7,599; women: 10,009) from the Korean National Health and Nutrition Examination Survey 2008-2011 was included in this study. The participants were divided into the derivation and validation groups via a random number generator (with a ratio of 70:30). The prediction equations were developed using a series of multivariable linear regressions and validated using the Bland-Altman plot and intraclass correlation coefficient (ICC). RESULTS: The initial and practical equations that included age, height, weight, and waist circumference had a different predictive ability for LBM (men: R2 = 0.85, standard error of estimate [SEE] = 2.7 kg; women: R2 = 0.78, SEE = 2.2 kg), ASM (men: R2 = 0.81, SEE = 1.6 kg; women: R2 = 0.71, SEE = 1.2 kg), and BFM (men: R2 = 0.74, SEE = 2.7 kg; women: R2 = 0.83, SEE = 2.2 kg) according to sex. Compared with the first prediction equation, the addition of other factors, including serum creatinine level, physical activity, smoking status, and alcohol use, resulted in an R2 that is higher by 0.01 and SEE that is lower by 0.1. CONCLUSIONS: All equations had low bias, moderate agreement based on the Bland-Altman plot, and high ICC, and this result showed that these equations can be further applied to other epidemiologic studies.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.234-236
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• 2004

The purpose of this study is to establish the predictive equation of welding distortion at the thick AA5083 alloy weldment. In order to do it, the extensive FE analysis was peformed to identify the principal factor controlling welding distortion. Based on the results, the predictive equations of transverse shrinkage and angular distortion at the thick AA5083 alloy weldment were formulated as the function of heat intensity (Q), in-plane(Di) and bending(Db) rigidity.

• Nutrition Research and Practice
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• v.9 no.4
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• pp.370-378
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• 2015

BACKGROUND/OBJECTIVES: Athletes generally desire changes in body composition in order to enhance their athletic performance. Often, athletes will practice chronic energy restrictions to attain body composition changes, altering their energy needs. Prediction of resting metabolic rates (RMR) is important in helping to determine an athlete's energy expenditure. This study compared measured RMR of athletic and non-athletic adolescents with predicted RMR from commonly used prediction equations to identify the most accurate equation applicable for adolescent athletes. SUBJECTS/METHODS: A total of 50 athletes (mean age of $16.6{\pm}1.0years$, 30 males and 20 females) and 50 non-athletes (mean age of $16.5{\pm}0.5years$, 30 males and 20 females) were enrolled in the study. The RMR of subjects was measured using indirect calorimetry. The accuracy of 11 RMR prediction equations was evaluated for bias, Pearson's correlation coefficient, and Bland-Altman analysis. RESULTS: Until more accurate prediction equations are developed, our findings recommend using the formulas by Cunningham (-29.8 kcal/day, limits of agreement -318.7 and +259.1 kcal/day) and Park (-0.842 kcal/day, limits of agreement -198.9 and +196.9 kcal/day) for prediction of RMR when studying male adolescent athletes. Among the new prediction formulas reviewed, the formula included in the fat-free mass as a variable [$RMR=730.4+15{\times}fat-free\;mass$] is paramount when examining athletes. CONCLUSIONS: The RMR prediction equation developed in this study is better in assessing the resting metabolic rate of Korean athletic adolescents.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.11
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• pp.1628-1633
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• 2017

The purpose of this study was to identify the difference and correlation in elbow joint maximal flexion strength according to measurement methods and characteristics of muscular contraction, and to develop the predictive equation of elbow joint maximal flexion strength for the optimal exercise intensity setting and accurate measurement. Subjects were 30 male university students. Elbow joint maximal flexion strength of isokinetic contraction, isometric contraction at $75^{\circ}$ elbow joint flexion position, isotonic concentric 1RM, manual muscle strength (MMT) were measured with isokinetic dynamometer, dumbbell, and manual muscle tester. Pearson's r, linear regression equation, and multiple regression equation between variables were calculated. As a result, the highest value was isometric contraction. The second highest value was MMT. The third highest value was isokinetic contraction. 1RM was the lowest. Predictive equations of elbow joint maximal flexion strength between isometric and isokinetic contraction, between isometric contraction and 1RM, among isometric contraction, 1RM, and body weight were developed. In conclusion, 1RM and isokinetic elbow joint maximal flexion strength could be seemed to underestimate the practical elbow joint maximal flexion strength. And it is suggested that the developed predictive equations in this study should be useful in criteria- and goal-setting for resistant exercise and sports rehabilitation after elbow joint injury.

• Tuberculosis and Respiratory Diseases
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• v.69 no.2
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• pp.108-114
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• 2010

Background: The aim was to estimate the differences between pulmonary disability grades according to the spirometry reference equations (the Korean equation and the Morris equation). Methods: Spirometry was performed on 16,916 male and 1,353 female special examination for pneumoconiosis, in the period of 2007~2009. Changes in predictive values for forced expiratory volume in one second ($FEV_1$), forced vital capacity (FVC) and $FEV_1$/FVC and in disability grade were evaluated using both equations. Results: Mean FVCs for men and women were 4,218.7 mL and 2,801.5 mL in predictive values after the application of the Korean equation, and 3,763.9 mL and 2,395.6 mL after the Morris equation, respectively. Compared with the Morris equation, the Korean equation showed 10.8% and 14.5% of excesses for men and women (p<0.001). Mean $FEV_1s$ for men and women were 3,102.5 mL and 2,107.1 mL in the Korean equation, and 2,667.8 mL and 1,699.6 mL in the Morris equation, respectively. Compared with the Morris equation, the Korean equation showed 14.0% and 19.3% of excesses for men and women (p<0.001). Men and women who showed the changes of disability grades using the Korean equation in place of the Morris equation were 23.9% (4,052/16,916) and 22.9% (311/1,353) on FVC, and 23.1% (3,913/16,916) and 10.7% (145/1,353) on $FEV_1$. Conclusion: Applying different reference equations for spirometry has resulted in changes for disability grades in special examination for pneumoconiosis.

• Journal of Welding and Joining
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• v.26 no.3
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• pp.23-29
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• 2008

The purpose of this study is to propose the proper fillet welding process for preventing the buckling distortion in thin panel welded structure. In order to do it, a heat input model for laser hybrid welding process was developed using FEA and experiment. The principal factors controlling the angular distortion and longitudinal shrinkage force caused by FCA and laser hybrid welding were identified as the welding heat input and weld rigidity using FEA. The predictive equations of angular distortion and longitudinal shrinkage force for each welding process were formulated as a function of the principal factors proposed. With the predictive equations, the buckling distortion at the thin panel welded structure with welding process was evaluated and compared using nonlinear buckling analysis and STEM(simplified thermo elastic method). Based on the results, the best way to prevent the buckling distortion at the given welded panel structures was identified as an intermittent FCA welding.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.1
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• pp.61-67
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• 2000

It was the aim of present study to grope the relationship of the maxillary first molar width to the various transverse skeletal measurements in frontal headfilm, and to formulate the predictive equations of the maxillary intermolar width (U6-U6) from each of the variables. Frontal cephalograms of 17 males from 18 to 26 YO and 13 females from 17 to 25 YO who manifested balanced skeletal profiles, normal occlusion, and no history of orthodontic and prosthodontic treatment were employed as subjects. Nine transverse measurements were scrutinized with Pearson's correlation analysis, simple and stepwise multiple regression analysis in specific regards to the intermolar width of maxillary first molar. Statistical output demonstrated that there were intimate relationships within the various transverse skeletal measurements each other, and among the others, high correlation was found between facial width and maxillary first intermolar width. Regression analyses provided the reliable and clinically applicable predictive equations to set the ideal maxillary first intermolar width(U6-U6) from the given skeletal framework.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.42-48
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• 1999

Three experiments were conducted to develop and test equations for predicting carcass composition. In the first study using 52 d-old Cobb ${\times}$ Cobb male broilers, twenty four carcasses were selected from 325 processed birds based upon visual appraisal for abdominal fat (low, medium, high) and assayed for specific gravity (SG), dry matter (DM), fat, protein, and ash. In experiment 2, 120 birds were fed rations containing 2 caloric densities (2,880 and $3,200kcal\;ME_n/kg$ diet) and assayed as described above on weeks 2,3,4,5, and 6. Carcass fat was elevated (p < 0.05) with increased caloric density. In both studies predictive variables were significantly correlated with chemically determined carcass fat, protein, and ash contents. Pooled across the 2 studies, data were used to form SG, DM, and or age based equations for predicting carcass composition. Results were tested in experiment 3, where 576 birds reared to 49-d consumed either 2,880, 3,200, or $3,574kcal\;ME_n/kg$ diet while exposed to constant $24^{\circ}C$ or cycling 24 to $35^{\circ}C$ ambient temperatures. Both dietary and environmental effects impacted (p < 0.05) carcass composition. The fat content analyzed chemically was enhanced from 12.4 to 15.7%, and predicted fat was also elevated from 13.4 to 14.8% with increasing caloric density. Heat distress reduced (p < 0.05) analyzed carcass protein (18.9 vs 18.3%) and predicted protein (18.2 vs 17.5%). Predicted equation values for carcass fat, protein, ash, and energy were correlated with the chemically analyzed values at r=0.96, 0.77, 0.86, and 0.79, respectively. Results suggest that prediction equations based on DM and SG may be used to estimate carcass fat, protein, ash, and energy contents of broilers consuming diets that differ in caloric density (2,800 to $3,574kcal\;ME_n/kg$) and for broilers exposed to either constant ($24^{\circ}C$) or cycling high (24 to $35^{\circ}C$) ambient temperatures during 49-d rearing period tested in the present study.