• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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• pp.469-473
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• 1987

This paper presents a method to estimate p.d.f.(probability density function) of harmonic phasor voltage. Because the quantity of harmonics is not fixed, stochastic analysis of harmonics is needed. Because it is impossible to obtain p.d.f. of voltage from p.d.f. of current directly, the moments of voltage and current are used. Firstly, the moments of current is calculated from p.d.f. of current. Secondly, the moments of voltage are calculated from the moments of current using the linearity of the moments. Finally, p.d.f. of voltage is estimated from the moments of voltage using Gram-Charlier Type A Series. [1] The moments of the p.d.f. obtained by the series and of the true p.d.f. is same up to given finite moments. Because current and voltage of harmonics are represented as not instantaneous values but phasors, the estimated value can be compared with the measured value and harmonic phasor voltage can be analyzed when the p.d.f. of phase is nonuniform as well as uniform.

• 대한수학회보
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• 제46권1호
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• pp.183-198
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• 2009

In this paper, we derive a characterization of orthonormal balanced multiwavelets of order p in terms of the continuous moments of the multiscaling function $\phi$. As a result, the continuous moments satisfy the discrete polynomial preserving properties of order p (or degree p - 1) for orthonormal balanced multiwavelets. We derive polynomial reproduction formula of degree p - 1 in terms of continuous moments for orthonormal balanced multiwavelets of order p. Balancing of order p implies that the series of scaling functions with the discrete-time monomials as expansion coefficients is a polynomial of degree p - 1. We derive an algorithm for computing the polynomial of degree p - 1.

• Water Engineering Research
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• 제4권3호
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• pp.155-173
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• 2003

Parameters and quantiles of the 2-parameter generalized Pareto distribution were estimated using the methods of regular moments, modified moments, probability weighted moments, linear moments, maximum likelihood, and entropy for Monte Carlo-generated samples. The performance of these seven estimators was statistically compared, with the objective of identifying the most robust estimator. It was found that in general the methods of probability-weighted moments and L-moments performed better than the methods of maximum likelihood estimation, moments and entropy, especially for smaller values of the coefficient of variation and probability of exceedance.

• 가정∙방문간호학회지
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• 제25권2호
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• pp.165-174
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• 2018

Purpose: The study investigated the knowledge and compliance on hand hygiene moments among nursing care workers in geriatric hospitals. Methods: A total of 143 nursing care workers at geriatric hospitals were selected. Data collection was conducted from February 20 to March 20, 2017. Results: For all hand hygiene scenarios, the total correct answer rate was 71.5%. On the necessary hand hygiene moments, the compliance rate was 68.3%. With respect to the general characteristics of the participants, knowledge on hand hygiene moments showed a statistically significant difference according to clinical career(p=.001), and existence of infection controller or infection control office in the nursing home(p=.038). Compliance showed differences according to clinical career(p=.023), existence of infection controller or infection control office in the nursing home(p=.033), and training experience in hand hygiene(number of times/year)(p=.035). Knowledge and compliance showed a statistically significant positive correlation(r=.90, p<.001). Conclusions: It is necessary to develop and operate an infection control education program that can improve the knowledge and awareness of hand hygiene moments and considers the individual characteristics geriatric hospitals's nursing care workers.

• Communications for Statistical Applications and Methods
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• 제16권4호
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• pp.647-658
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• 2009

It is already known from the previous study that flood seems to have heavier tail. Therefore, to make prediction of future extreme label, some agreement of tail behavior of extreme data is highly required. The LH-moments estimation method, the generalized form of L-moments is an useful method of characterizing the upper part of the distribution. LH-moments are based on linear combination of higher order statistics. In this study, we have formulated LH-moments of five distributions useful in hydrology such as, two types of three parameter kappa distributions, beta-${\kappa}$ distribution, beta-p distribution and a generalized Gumbel distribution. Using LH-moments reduces the undue influences that small sample may have on the estimation of large return period events.

• 호남수학학술지
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• 제21권1호
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• pp.115-126
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• 1999

Some discrete inequalities of $Gr{\ddot{u}}ss$ type and their applications in estimating the p-moments of guessing mapping are given.

• Journal of the Korean Statistical Society
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• 제36권3호
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• pp.357-365
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• 2007

In this paper we present characterizations of the Pareto, Lomax, exponential and beta models by some properties of their $r^{th}$ partial moment defined as ${\alpha}_r(t)=E[(X-t)^+]^r$, where $(X-t)^+ = max(X-t,0)$. Given the partial moments at a few truncation points, these results enable us to calculate the moments at many other points.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6160-6168
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• 2015

의료기관 종사자의 손 위생 수행은 의료관련 감염의 전파를 예방하는 가장 효과적인 방법이다. 본 연구는 직종별 손 위생 수행 측정과 분석을 위해 세계보건기구(WHO)의 손 위생 수행 평가도구를 이용한 직접관찰방법으로 2010년 10월 25일부터 12월 31일까지 수행되었으며, SPSS 21.0으로 기술분석, 교차분석, 다중로지스틱분석을 하였다. 총 8,644 건의 손 위생 상황이 관찰되었고, 손 위생 수행률은 94.1%였으며 의사가 가장 낮았다(83.3%; OR:0.209, 95%CI:0.174-0.252). 직종별 수행률(p<0.001), WHO에서 권고하는 5개 상황(WHO's 5Moments)별 수행률은(p<0.001) 유의한 차이를 보였으며, 간호사(p=0.003)와 의료기사직(p<0.001)이었다. 본 연구결과 손 위생 수행률 향상을 위한 직종별 특성화된 손 위생 전략과 WHO's 5Moments에 따라 차별화된 전략 개발이 필요할 것으로 사료된다.

• 한국운동역학회지
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• 제16권3호
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• pp.105-115
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• 2006

The purpose of this study is to elucidate the mechanical characteristics of lower extremity joint movements at different walking speeds in obese people and suggest the very suitable exercise for obese person's own body weight and basic data for clinical application leading to medical treatment of obesity. This experimental subjects are all males between the ages of 20 and 30, who are classified into two groups according to Body Mass Index(BMI): one group is 15 people with normal body weight and the other 15 obese people. Walking speed is analysed at 3 different speeds ($1.5^m/s$, $1.8^m/s$, $2.1^m/s$) which is increased by $0.3^m/s$ from the standard speed of $1.5^m/s$. We calculated joint moments of lower extremity during stance phase through video recording and platform force measurement.Two-way ANOVA(Analysis of Variance, Mix) is applied to get the difference of moments according to walking speeds between normal and obese groups. Pearson's Correlation Analysis is applied to look into correlation between walking speeds and joint moments in both groups. Significance level of each experiment is set as ${\alpha}=.05$. As walking speed increases maximum ankle plantar flexion moment in the stance phase is smaller in obese group than in normal group, which is suggestive of weak toe push-off during terminal stance in obese group, and the highest maximum ankle plantar flexion moment in obese group during the middle speed walking($1.8^m/s.$). Maximum ankle dorsal flexion moment in obese group is relatively higher than in normal group and this is regarded as a kind of compensatory mechanism to decrease the impact on ankle when heel contacts the floor. Maximum knee flexion and extension moments are both higher in normal group with an increase tendency proportional to walking speed and maximum hip flexion and extension moments higher in obese group. In summary, maximum ankle plantar flexion moment between groups(p<.025), maximum knee moment not in flexion but in extension(p<.001) within each group according to increasing walking speed, and maximum hip flexion and extension moment(p<.001 and p<.004, respectively according to increasing walking speed are statistically significant but knee and hip moments between groups are not. Pearson correlation are different: high correlation coefficients in maximum knee flexion and extension moments, in maximum hip extension moment but not hip flexion, and in maximum ankle dorsal flexion moment but not ankle plantar flexion, in each group. We suspect that equilibrium imbalance develops when the subject increases walking speed and the time is around which he takes his foot off the floor.

• Journal of the Korean Statistical Society
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• 제32권2호
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• pp.193-202
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• 2003

We consider a double threshold AR-ARCH type process and give sufficient conditions under which the higher-order moments exist. Geometric ergodicity and strict stationarity are also studied.