• Geotechnical Engineering
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• v.2 no.1
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• pp.27-44
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• 1986

The measured soil data are analyzed to the descriptive statistics and classified into the four models of uncorrelated-normal (UNNO), uncorrelated-nonnormal (VNNN), correlatedonnormal(CONN), and correlated-nonnormal(CONN) . This paper presents the comparisons of reliability index and check points using the advanced first-order second-moment method with respect to the four models as well as BASIC Program. A sin91e-mode Performance function is consisted of the basic design variables of bearing capacity and settlements on shallow foundations and input the above analyzed soil informations. The main conclusions obtained in this study are summarized as follows: 1. In the bearing capacity mode, cohesion and bearing-capacity factors by C-U test are accepted for normal and lognormal distribution, respectively, and negatively low correlated to each other. Since the reliability index of the CONN model is the lowest one of the four model, which could be recommended a reliability.based design, whereas the other model might overestimate the geotechnical conditions. 2. In the case of settlements mode, the virgin compression ratio and preccnsolidation pressure are fitted for normal and lognormal distribution, respectively. Constraining settlements to the lower ones computed by deterministic method, The CONN model is the lowest reliability of the four models.

• Journal of the Korean Data and Information Science Society
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• v.9 no.2
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• pp.95-103
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• 1998

Azzalini and Bowman proposed the pseudo-likelihood ratio test for checking the linear relationship using kernel regression estimator when the error of the regression model follows the normal distribution. We modify their method with the bootstrap technique to construct a new test, and examine the power of our test through simulation. Our method can be applied to the case where the distribution of the error is not normal.

• Journal of the Korean School Mathematics Society
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• v.23 no.4
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• pp.427-448
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• 2020

The purpose of this study is to confirm the MKT(Mathematical Knowledge for Teaching) of the pre-service mathematics teachers on the normal distribution through the comparative analysis between the sub-elements of the MKT. In addition, it is to examine the factors that cause the difference of the subjects' MKT. To accomplish this, by the subject of 24 secondary pre-service mathematics teachers, in this study the test items of the MKT on the normal distribution were developed and data were collected and analyzed. As a result of the analysis of the MKT test sheet, the CCK(Common Content Knowledge) of the preparatory mathematics teacher was confirmed as a high score, whereas the SCK(Specialized Content Knowledge) and KCS(Knowledge of Content and Students) were confirmed as low scores. In addition, through these results, it could be confirmed that the difference in MKT of preparatory mathematicians occurred.

• Communications for Statistical Applications and Methods
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• v.2 no.2
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• pp.221-226
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• 1995

본 연구는 붓스트랩에 의한 U-통계량의 분산추정방법을 제안하고, 추정량의 일치성을 증명하였다. 결과적으로 붓스트랩 추정량으로 표준화한 U-통계량의 값이 표준정규분포에 근사함을 보였다. 또한 실제적인 비모수검정에서 이를 응용하여 검정력과 특성을 연구하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.3
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• pp.75-83
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• 1984

The probability of failure is used to analyze the reliability of three dimensional slope failure, instead of conventional factor of safety. The strength parameters are assumed to be normal variated and beta variated. These are interval estimated under the specified confidence level and maximum likelihood estimation. The pseudonormal and beta random variables are generated using the uniform probability transformation method according to central limit theorem and rejection method. By means of a Monte-Carlo Simulation, the probability of failure is defined as; $P_f=M/N$ N: Total number of trials M: Total number of failures Some of the conclusions derived. from the case study include; 1. Three dimensional factors of safety are generally much higher than 2-D factors of safety. However situations appear to exist where the 3-D factor of safety can be lower than the 2-D factor of safety. 2. The $F_3/F_2$ ratio appears to be quite sensitive to c and ${\phi}$ and to the shape of the 3-D shear surface and the slope but not to be to the unit weight of soil. 3. From the two models (normal, beta) considered for the distribution of the factor of safety, the beta distribution generally provides lager than normal distribution. 4. Results obtained using the beta and normal models are presented in a nomgraph relating slope height and slop angle to probability of failure.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.194-196
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• 1999

대기나 수용액 속에 부유 입자는 서로 충돌하여 합쳐져서 그 크기가 커지게 된다. 이러한 과정을 응집(Coagulation)이라고 하며, 이는 대기중 부유입자의 농도 및 크기분포의 변화, 구름 속에서의 빗방울형성 등에 매우 중요한 기작 중의 하나이다. 응집방정식은 일반적으로 비선형 편미적분 방정식으로 표현되어 일반 해를 구하는 것은 불가능하다. 이러한 이유로 응집방정식을 풀 때에는 수치 해석적인 방법이 주로 이용되고 있다.(Tolof, 1977; Gelbard and Seinfeld, 1978; Reed ea al., 1980; Mick et al., 1991).(중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5B
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• pp.431-438
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• 2011

This study investigated the problem of mean-field bias correction under the assumption that the radar and rain gauge rainfall data follow the log-normal distribution. Regression curves for the average, median and mode of the radar and rain gauge rainfall were derived and evaluated for their usefulness. Additionally, these regression curves were compared with those derived under the assumption that the radar and rain gauge data follow the normal distribution. This study investigated the regression results for the Typhoon Meami occurred in 2003 as an example. As results, three regression lines with the radar rainfall as the independent variable were found to underestimate the rainfall, while those with the rain gauge rainfall as the independent variable to overestimate. Among three types of regression curves considered, the result for the average was most appropriate. However this case was found to be inferior to the regression line passing the origin under the assumption of the normal distribution with the rain gauge rainfall as its independent variable. So it was hard to conclude that the consideration of the log-normality on the correction of radar rainfall is beneficial.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.16 no.3
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• pp.152-161
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• 2004

Double-peak normal distribution function was suggested as the probability density function of the tidal elevation data in Korean coastal zone. Frequency distribution analysis was carried out using hourly tidal elevation data of the ten tidal gauging stations, i.e., Incheon, Kunsan, Mokpo, Cheju, Yeosu, Masan, Gadeokdo, Pusan, Pohang, and Sokcho which were served through the Internet Homepage by the National Ocean Research Institute. Based on the RMS error and $R^2$ value comparison analysis, it was found that this suggested function as the probability density function of the tidal elevation data was found to be more appropriate than the normal distribution function. The parameters of the double-peak function were estimated optimally using Levenberg-Marquardt method which was modified from the Newton method. The estimated parameters were highly correlated with the non-tidal constants of the tidal gauging stations.

• The Korean Journal of Applied Statistics
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• v.33 no.6
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• pp.713-722
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• 2020

Contrasted with the standard symmetric GARCH models, we consider a broad class of threshold-asymmetric models to analyse financial time series exhibiting asymmetric volatility. By further introducing power transformations, we add more flexibilities to the asymmetric class, thereby leading to power transformed and asymmetric volatility models. In particular, the paper is concerned with the nonstationary volatilities in which conditions for integrated volatility and explosive volatility are separately discussed. Dow Jones Industrial Average is analysed for illustration.

• Journal of the Korean Magnetics Society
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• v.12 no.1
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• pp.20-23
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• 2002

The local coercivity distribution of CoCrPt alloy films prepared by dc magnetron sputtering has been investigated by means of a magneto-optical microscope magnetometer (MOMM) capable of simultaneously measuring the local properties on 400 nm spatial resolutions. Serial samples of CoCrPt alloy films were prepared with the Pt composition of a range from 6 to 28 at. %. We find that the local coercivity distribution crosses over from Gaussian to non-Gaussian distribution in CoCrPt alloy films with increasing Pt composition, with increasing trends in the width of the distribution as well as the average local coercivity. Transmission electron microscopy (TEM) studies reveal that our findings are closely correlated with the dependences of the grain size distribution and its average size on Pt concentration.