• Title/Summary/Keyword: Significance probability

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A Study on the Prevention Measures of Human Error with Railway Drivers (열차 운전 종사자를 대상으로 한 인적오류의 개선 방안 연구)

  • Kim, Dong Won;Song, Bo Young;Lee, Hi Sung
    • Journal of the Korean Society of Safety
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    • v.34 no.1
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    • pp.76-81
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    • 2019
  • In this study, the causes of human error were identified through the survey of the drivers of the three organizations: Seoul Metro, Seoul Metropolitan Rapid Transit Corporation, and Korail. It was started with the aim of finding and eliciting causes in various directions including human factors, job factors, and environmental factors. The Cronbach alpha value was 0.95 for the reliability significance of the stress-induced factors in the operational area. The significance probability for organisational factors was shown to be 0.82, and the significance of the sub-accident experience and the driving skill factors in operation was 0.81 In addition, the analysis results showed that stress-induced in the field of driving is higher than the human factors in the reliability analysis. The results of the analysis confirmed that the reliability of the organizational and operational stress-induced factors was higher than other causes. In order to reduce urban railroad accidents, this paper suggests a method for operating safe urban railroad through the minimization human errors.

Implementation Strategy of Hypothesis Decision Using Rejection Region Approach and P-Value Approach (RR 접근방법과 P-Value 접근방법을 이용한 가설판정의 적용방안)

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2012.11a
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    • pp.431-434
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    • 2012
  • The paper reviews properties of hypothesis decision approaches using rejection region and significance probability. The study also presents the guidelines for quality practioners to implement most useful hypothesis testing techniques such as RR(Rejection Region) approach and P-Value approach.

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ASYMPTOTIC DISTRIBUTION OF THE DISCOUNTED PROPER DEFICIT IN THE DISCRETE TIME DELAYED RENEWAL MODEL

  • Bao, Zhen-Hua;Wang, Jing
    • Bulletin of the Korean Mathematical Society
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    • v.48 no.2
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    • pp.325-334
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    • 2011
  • In this paper we consider the discrete time delayed renewal risk model. We investigate what will happen when the distribution function of the discounted proper deficit is asymptotic in the initial surplus. In doing this we establish several lemmas regarding some related ruin quantities in the discrete time delayed renewal risk model, which are of significance on their own right.

On Estimating the Parameters of an Extended Form of Logarithmic Series Distribution

  • Kumar, C. Satheesh;Riyaza, A.
    • Communications for Statistical Applications and Methods
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    • v.20 no.5
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    • pp.417-425
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    • 2013
  • We consider an extended version of a logarithmic series distribution and discuss the estimation of its parameters by the method of moments and the method of maximum likelihood. Test procedures are suggested to test the significance of the additional parameter of this distribution and all procedures are illustrated with the help of real life data sets. In addition, a simulation study is conducted to assess the performance of the estimators.

A Preliminary Study on the Preference Assessment on Individuals with Specific Display Location in Screen based on Electroencephalogram and Emotional Assessment (뇌파와 감성평가 기반의 스크린 상 특정 디스플레이 위치 선호도 평가에 관한 기초연구)

  • Wang, ChangWon;Min, Se Dong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.7
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    • pp.968-975
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    • 2014
  • This paper proposed a evaluation method for individual's subjective preferred location using EEG and emotional assessment. Visual stimulus were sequentially presented a total six points(the top and the bottom of the left, the top and the bottom of the center and the top and the bottom of the right on the screen). EEG were measured from twenty subjects according to each six points. At the same time, we were executed evaluation of subjects preferred location from emotional assessment. Alpha and beta wave were measured in Fp1, Fp2, F7 and F8 location, followed by ten to twenty electrode system. Correlations and variations of alpha and beta wave from each channel were calculated and analyzed. Because of the number of subjects population under 30, we used Speareman test for a correlation analysis between alpha and beta wave. Also, emotional assessments which compose of visual sense harmony, visual sense stability, stability of position and the visibility were performed and were analyzed by average and frequency. After visual stimulus, emotional assessments were performed. From the variance analysis of EEG, beta wave from F7 was appeared statistically significant as significance probability of 0.006. Also, between alpha wave and beta wave appeared a negative correlation(r=-0.190). From the post-hoc test of F7 beta wave, location 1, 5 and 6 appeared to difference statistically significant. Emotional assessment result according to six positions showed 0.00 significance probability. Thus, location and emotional assessment appeared to influence on each other. From the average and frequency analysis of emotional assessment, location 2 showed obtained of best emotional assessment score and appeared lower beta wave than other locations. Finally, most subjects showed a preference for location 2. Through obtained results in this paper, will be helpful to about human emotional assessment and EEG research.

A study on the validity to make a diagnosis of Soeumin by QSCC II (Questionnaire for the Sasang Constitution Classification II) (사상체질분류검사지(四象體質分類檢査紙)(QSCC) II 에 의한 소음인(少陰人) 진단(診斷)의 타당성(妥當性) 연구(硏究))

  • Lee, Su-Kyung;Lee, Eui-Ju;Koh, Byung-Hee;Song, Il-Byung;Kim, Sang-Bok
    • Journal of Sasang Constitutional Medicine
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    • v.12 no.2
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    • pp.94-103
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    • 2000
  • The purpose of this study is to examine validity to Soeum scales by QSCC II. For this study, the objects are 336 patients who were made a diagnosis of Soeumin and 422 patients of other constitutions in Oriental Medicine & Western Medicine Cooperative Health Examination Center KyungHee University Medical Center. A systematic analysis has been made and the results are as follows. 1. We made a frequency analysis in 758 examinees' questions and concluded that 35 questions, among which 30 questions were existing and 5 were new, had statistical significance in making a diagnosis of Soeumin by more than 10% in comparison with answer frequency of other constitutions. 2. Because confidence coefficient of 0.8011 revised Soeum scales(35) rises up as compared with that of 0.6319 existing Soeum scales(51), I think revised Soeum scales reflect trait of Soeumin well and it is liable to shorten question time by controling questions. 3. Soeumin's discrimination probability in Soeumin was 55.4% by QSCCII, but that rises up to 64.3% by discriminant function made by revised Soeum scales. So there is statistical significance in discriminant function. 4. When questions in QSCCII are divided into body-spirit(體形氣像), looks-attitude(容貌詞氣), temper- talent(性質才幹), continuous mind(恒心), avarice(心慾), physiological symptoms(生理的 證) and pathological symptoms(病理的 證), response frequency and constitution discrimination probability falls in questions about avarice and pathological symptoms.

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Effect of Gait Training in Chronic Hemiplegia Patients with Inducement to Vision and Rhythmic Auditory Stimulation (마비측 시야 유도 보행 훈련과 리듬 청각 자극 훈련이 만성 뇌졸중 환자들의 보행에 미치는 효과)

  • Kim, Tae-Hyun;Choi, Jong-Duk;Youn, Hae-Jin
    • PNF and Movement
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    • v.12 no.3
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    • pp.151-158
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    • 2014
  • Purpose: The purpose of the study is to see the effect of walking when training for chronic stroke patients, Affected side vision impairment induced gait training with rhythmic auditory stimulation in parallel. Methods: This study was the general walking training group, the training group was divided damage induced affected side view, affected side view damage induced by rhythm auditory stimulation training three groups. Intervention period was 4 weeks. 5 times per week, per 30 min entered arbitration. Affected Side vision impairment induced induction training was conducted by installing a red cones, rhythmic auditory stimulation was applied to a regular rhythm training using a smartphone application (Metronome). Paired t-test was performed to see the difference between each group and before the intervention. One-way ANOVA was used to find out the significance probability between each group. Statistical significance was set at 0.05 probability. Results: Regular walking group, rather than affected side vision guided walking group could see increases in the FGA and DGI (P<0.05). And vision impairment induced affected side view and rhythmic auditory stimulation induction training this group than in the combination group walking group obtained higher scores on the FGA, DGI score(P<0.05). Conclusion: If you want to enforce certain rhythmic auditory stimulation of the visual field and side damage induced during gait training for stroke patients will be able to expect a better effect.

NUMBER OF CYCLES IN EVOLUTIONARY OPERATION

  • Lim, Yong-B.;Park, Sung-H.
    • Journal of the Korean Statistical Society
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    • v.36 no.2
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    • pp.201-208
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    • 2007
  • Evolutionary operation (EVOP) proposed by Box (1957) is a method for continuous monitoring and improvement of a full-scale manufacturing process with the objective of moving the operating conditions toward the better ones. EVOP consists of systematically making small changes in the levels of the two or three process variables under consideration. Data are collected on the response variable at each point of two level factorial design with the center point and a cycle is said to have been completed. The cycles are replicated sequentially until the decision is made on whether further cycle of experiments is needed to conclude the significance of any of main effects or interaction effects or the curvature. In this paper, an improved flow chart of EVOP is proposed and how to determine the number of cycles is studied based on the size of type II error. In order to reject the alternative hypothesis of interests with more confidence and conclude that we believe in the null hypothesis of no effects, we propose a counter measure $p^*-value$ corresponding to the p-value. The relationship of $p^*-value$ to the probability of type II error ${\beta}$ under the alternative hypothesis of interests is analogous to that of p-value to the probability of type I error ${\alpha}$. Also the implementation of EVOP with a mixture experiment is discussed.

Optimum Selection of Equalizer Taps Losing Noise Power Estimation (잡음 전력 추정을 이용한 등화기 탭의 최적 선택 방법)

  • 성원진;신동준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.12A
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    • pp.1971-1977
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    • 2001
  • Multipath Rayleigh fading channels for mobile radio transmission can be represented by the linear filter model, and depending on the delay path characteristics, only a selected number of taps may have significance in the receiver structure design. By using tap-selective equalization, reduction in both processing complexity and power consumption can be obtained. In this paper, we present an optimal tap selection method for a given channel model, and demonstrate the performance improvement over an existing method. We show the method performs the CFAR (Constant False Alarm Rate) detection when the noise power information is available, and derive exact expressions of the error probability for the case of noise power estimation. Using the derived formulas and simulation results, it is demonstrated that the error probability quickly approaches to the optimal performance as the number samples used for the noise power estimation increases.

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Change-point and Change Pattern of Precipitation Characteristics using Bayesian Method over South Korea from 1954 to 2007 (베이지안 방법을 이용한 우리나라 강수특성(1954-2007)의 변화시점 및 변화유형 분석)

  • Kim, Chansoo;Suh, Myoung-Seok
    • Atmosphere
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    • v.19 no.2
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    • pp.199-211
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    • 2009
  • In this paper, we examine the multiple change-point and change pattern in the 54 years (1954-2007) time series of the annual and the heavy precipitation characteristics (amount, days and intensity) averaged over South Korea. A Bayesian approach is used for detecting of mean and/or variance changes in a sequence of independent univariate normal observations. Using non-informative priors for the parameters, the Bayesian model selection is performed by the posterior probability through the intrinsic Bayes factor of Berger and Pericchi (1996). To investigate the significance of the changes in the precipitation characteristics between before and after the change-point, the posterior probability and 90% highest posterior density credible intervals are examined. The results showed that no significant changes have occurred in the annual precipitation characteristics (amount, days and intensity) and the heavy precipitation intensity. On the other hand, a statistically significant single change has occurred around 1996 or 1997 in the heavy precipitation days and amount. The heavy precipitation amount and days have increased after the change-point but no changes in the variances.