• Journal of the Korean Statistical Society
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• v.33 no.3
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• pp.323-337
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• 2004

This article coined a general class of estimators for various measures in normal population when some' a priori' or guessed value of standard deviation a is available in addition to sample information. The class of estimators is primarily defined for a function of standard deviation. An unbiased estimator and the minimum mean squared error estimator are worked out and the suggested class of estimators is compared with these classical estimators. Numerical computations in terms of percent relative efficiency and absolute relative bias established the merits of the proposed class of estimators especially for small samples. Simulation study confirms the excellence of the proposed class of estimators. The beauty of this article lies in estimation of various measures like standard deviation, variance, Fisher information, precision of sample mean, process capability index $C_{p}$, fourth moment about mean, mean deviation about mean etc. as particular cases of the proposed class of estimators.

• Bulletin of the Korean Mathematical Society
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• v.35 no.3
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• pp.547-557
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• 1998

In this paper, we study submanifolds in the Euclidean space with parallel normal mean curvature vectorand special quadric representation. Especially we give a complete classification result relative to surfaces satisfying these conditions.

• Journal of Environmental Impact Assessment
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• v.23 no.4
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• pp.285-295
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• 2014

In this study, we analyzed probability distribution of EMCs (Event Mean Concentration) of COD, TOC, T-N, T-P and SS from rice paddy fields and compared the mean values of observed EMCs and the median values of estimated EMCs ($EMC_{50}$) through probability distribution. The field monitoring was conducted during a period of four crop-years (from May 1, 2008, to September 30. 2011) in a rice cultivation area located in Emda-myun, Hampyeong gun, Jeollanam-do, Korea. Four probability distributions such as Normal, Log-normal, Gamma, and Weibull distribution were used to fit values of EMCs from rice paddy fields. Our results showed that the applicable probability distributions were Normal, Log-normal, and Gamma distribution for COD, and Normal, Log- Normal, Gamma and Weibull distribution for T-N, and Log-normal, Gamma and Weibull distribution for T-P and TOC, and Log-normal and Gamma distribution for SS. Log-normal and Gamma distributions were acceptable for EMCs of all water quality constituents(COD, TOC, T-N, T-P and SS). Meanwhile, mean value of observed COD was similar to median value estimated by the gamma distribution, and TOC, T-N, T-P, and SS were similar to median value estimated by log-normal distribution, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.41-56
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• 1984

The purpose of this study is to obtain the normal range of mandibular movement for 13 year old boys and girls, and to compare it to the range of mandibular movement of class III patient and normal adult for diagnosis and prognosis of class III malocclusion and TMJ dysfunction. The subjects were 20 normal boys 20 normal girls 22 class III boys and 18 class III girls. The author measured the ranges and shapes of movement of the mandible in the frontal, sagittal and horizontal trajectories using Saphon visitrainer C II (Tokyo Shizaisha Inc.) for the subjects. The results obtained are as follows: 1) The mean for maximum right laterotrusion in the frontal trajectory were 11.96mm in N.B., 11.10mm in N.G., 11.32mm in III. B., 11.24mm in III G. The mean for maximum left laterotrusion were 11.48mm, 11.0mm, 10.91mm, 10.44mm respectively, Area of border movement were 7.16cm in N.B., 6.59cm in N.G., 7.29cm in III. B., 7.50cm in III. G. 2) The mean for maximum protrusion in the sagittal trajectory were 11.7mm in N.B., 11.4mm in N.G.,11.87mm in III B., and 11.02mm in III. G. 3) The mean for maximum protrusion in the horizontal trajectory were 10.20mm in N.B.,10.00 mm in N.G., 9.12mm for III. B. and 9.36mm in III. G. 4) The mean for maximum protrusion of Class III subjects were shorter than those of normal subjects. 5) There was no sexual difference in the range of mandibular movement for 13 year old subjects. N.B; Normal boys N.G.; Normal girls III.B.; Class III boys III. G.; Class III girls.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.297-308
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• 2010

This article deals with the problem of testing mean when the coefficient of variation in normal distribution is known. We propose Bayesian hypothesis testing procedures for the normal mean under the noninformative prior. The noninformative prior is usually improper which yields a calibration problem that makes the Bayes factor to be defined up to a multiplicative constant. So we propose the objective Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factor under the reference prior. Specially, we develop intrinsic priors which give asymptotically same Bayes factor with the intrinsic Bayes factor under the reference prior. Simulation study and a real data example are provided.

• Journal of the Korean Data and Information Science Society
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• v.23 no.3
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• pp.605-616
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• 2012

This article deals with the problem of testing on the common mean of several normal populations. We propose Bayesian hypothesis testing procedures for the common normal mean under the noninformative prior. The noninformative prior is usually improper and yields a calibration problem that makes the Bayes factor to be defined u to a multiplicative constant. So we propose the default Bayesian hypothesis testing procedures based on the fractional Bayes factor and the intrinsic Bayes factors under the reference priors. Simulation study and an example are provided.

• Journal of Oriental Neuropsychiatry
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• v.13 no.2
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• pp.93-100
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• 2002

Objects and Methods : BDl, STAI and Self-Esteem scale were completed by 28 female subjects who composed of nurses of Kyung Hee Medical Center and students of Kyung Hee Oriental Medical college. At the same time, current weight, height and BMI(Body Mass Index), ideal weight, height and BMI, the difference of current weight and ideal weight, the difference of current height and ideal height, and the difference of current BMI and ideal BMI were measured. Result : 1. There was a significant difference between obese and normal weight group in the difference between the current weight and the ideal weight. The difference of the obese group were higher than the normal weight group. 2. There was a significant difference between obese and normal weight group in the mean BDI score. The mean BDI score of the obese group were higher than that of the normal weight group. 3. There was no significant difference between obese and normal weight group in the mean STAI score. 4. There was no significant difference between obese and normal weight group in the mean Self-Esteem Scale score. Conclusion : There are a tendency; the more weight, the more depression in women.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.1 no.2
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• pp.21-29
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• 2006

Objective: The aim of this study is to investigate whether patients with temporomandibular disorder have more anxiety than normal people. Methods: Patients group(n=50) with TMD and normal group(n=30) without TMD and other disease completed STAl(State-Trait Anxiety Inventory), and there was comparison of mean scores between patients and normal groups. Results: The mean of total STAl scores of patients group was $91.32{\pm}20.32$, whereas that of normal group was $81.27{\pm}12.97(p<0.01)$. The mean of state-anxiety scores of patients group was $45.68{\pm}11.30$, whereas that of normal group was $40.70{\pm}7.28(p<0.05)$. The mean of trait-anxiety scores of patients group was $45.64{\pm}10.02$, whereas that of normal group was $40.57{\pm}7.22(p<0.05)$. There was a tendency that patients with TMD had more anxiety. So, doctors had better give attention to patients' anxiety when they treat the patients with TMD.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.3
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• pp.280-288
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• 1998

The purpose of this study was to evaluate the nutrient and food intake status in underweight female college students living in Seoul. 126 underweight(BMI<20) and 74 normal weight (20$\leq$BMI<25) students were asked for their daily food intake and eating habits by using 3-day food records and questionnaire. We analyzed the amounts of the nutrient intakes and food groups as the subjects. The mean of height and weight were 162.1cm and 49.0kg in underweight and 160.6cm and 54.9kg in normal weight subjects. The mean energy, iron, and vitamin A intakes among the students were smaller than RDA for Koreans. The mean calcium(p<0.01), sodium(p<0.05), and vitamin B$_2$(p<0.05) intakes in underweight subjects were significantly higher than those in normal weight subjects. Total food intakes of underweight and normal weight students were 1235.8g and 1078.1g, respectively. The mean of the pulse group in the underweight was significantly higher than that in normal group(p<0.01) Frequently consumed food or dish items of the subjects were Kimchi, cooked rice, and milk. In the relation between BMI and dietary factors, the BMI was found to have a significant negative correlation with calcium intake(p<0.05), pulse intake(p<0.01) and eating habit score(p<0.01) Eating habit scores about quantity of food and lipid intake showed a significant difference between underweight and normal students.

• Communications for Statistical Applications and Methods
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• v.10 no.2
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• pp.353-359
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• 2003

This paper deals with the problem of testing mean change with one change-point with the normal random variables. We propose a test with the mean difference for change in a location parameter. A power comparison study of various change-point test statistics is performed via Monte Carlo simulation with S-plus software.