• 한국국방경영분석학회지
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• 제28권2호
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• pp.56-69
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• 2002

A technique of finding both probability density and distribution function for interkilling times is considered and demonstrated. An important result is that any arbitrary interfiring time random variables fit to this study, The interfiring renewal density function given a certain interfiring probability density function can be applied to obtain the corresponding interkilling renewal density function which helps us to estimate the expected number of killing events in a time period. The numerical inversion of Laplace transformation makes these possible and the results appear to be excellent. In case of ammunition supply is limited, an alternative way of getting the probability density function of time to the killing is investigated. The convolution technique may give us a means of settling for this new problem.

• 제어로봇시스템학회논문지
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• 제14권9호
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• pp.865-872
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• 2008

Spacecraft attitude estimation using the nonlinear unscented filter is addressed to fully utilize capabilities of the unscented transformation. To release significant computational load, an efficient technique is proposed by reasonably removing correlation between random variables. This modification introduces considerable reduction of sigma points and computational burden in matrix square-root calculation for most nonlinear systems. Unscented filter technique makes use of a set of sample points to predict mean and covariance. The general QUEST(QUaternion ESTimator) algorithm preserves explicitly the quaternion normalization, whereas extended Kalman filter(EKF) implicitly obeys the constraint. For spacecraft attitude estimation based on quaternion, an approach to computing quaternion means from sampled quaternions with guarantee of the quaternion norm constraint is introduced applying a constrained optimization technique. Finally, the performance of the new approach is demonstrated using a star tracker and rate-gyro measurements.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.1100-1102
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• 1997

This paper presents a generalized multi-parameter distribution method for the convolution of linear combination of random variables to calculate system load flow in a conventional probabilistic approach and also presents a conceptual possibilistic approach using fuzzy set theory to manage uncertainties. The probability distribution function is transformed into an appropriate possibilistic representation under the compromise between the transformation consistency and the human updating experience. The IEEE 25-bus system is used to demonstrate the capability of the proposed algorithm.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1605-1614
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• 2013

This paper presents a probabilistic methodology for small signal stability analysis of power system with correlated wind sources. The approach considers not only the stochastic characteristics of wind speeds which are treated as random variables with Weibull distributions, while also the wind speed spatial correlations which are characterized by a correlation matrix. The approach based on the 2m+1 point estimate method and Cornish Fisher expansion, the orthogonal transformation technique is used to deal with the correlation of wind farms. A case study is carried out on IEEE New England system and the probabilistic indexes for eigenvalue analysis are computed from the statistical processing of the obtained results. The accuracy and efficiency of the proposed method are confirmed by comparing with the results of Monte Carlo simulation. The numerical results indicate that the proposed method can actually capture the probabilistic characteristics of mode properties of the power systems with correlated wind sources and the consideration of spatial correlation has influence on the probability of system small signal stability.

• Nuclear Engineering and Technology
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• 제50권7호
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• pp.1120-1130
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• 2018

An analysis of a pyroprocessing safeguards methodology employing the Pu-to-$^{244}Cm$ ratio is presented. The analysis includes characterization of representative used nuclear fuel assemblies with respect to computed nuclide composition. The nuclide composition data computationally generated is appropriately reformatted to correspond with the material conditions after each step in the head-end stage of pyroprocessing. Uncertainty in the Pu-to-$^{244}Cm$ ratio is evaluated using the Geary-Hinkley transformation method. This is because the Pu-to-$^{244}Cm$ ratio is a Cauchy distribution since it is the ratio of two normally distributed random variables. The calculated uncertainty of the Pu-to-$^{244}Cm$ ratio is propagated through the mass flow stream in the pyroprocessing steps. Finally, the probability of Type-I error for the plutonium Material Unaccounted For (MUF) is evaluated by the hypothesis testing method as a function of the sizes of powder particles and granules, which are dominant parameters to determine the sample size. The results show the probability of Type-I error is occasionally greater than 5%. However, increasing granule sample sizes could surmount the weakness of material accounting because of the non-uniformity of nuclide composition.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.1079-1089
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• 2021

The development of information technology has promoted organizational transformation through the utilization of an electronic information system. This research aimed to identify factors that influence continuous intention to use E-HRM. This empirical research applies the Technology Acceptance Model and Cognitive Model for identifying significantly impacted areas of continuous intention to use E-HRM in a highly dynamic environment. The data were collected using questionnaires delivered directly to respondents. The sample was 100 employees of ESQ Group selected through random sampling. The variables used were subjective norms (X1), perceived behavioral control (X2), perceived innovativeness (Y1), cognitive absorption (Y2), satisfaction (Y3), and continuous intention to use E-HRM (Y4). Statistical analysis using Structural Equation Modelling (SEM) with Smart PLS was applied. The results revealed that behavioral control (X2) did not influence the continuous intention to use E-HRM (Y4) and that cognitive absorption (Y2) and satisfaction (Y3) did not significantly influence continuous intention to use E-HRM (Y4). Subjective norms (X1) significantly influenced both perceived innovativeness (Y1) and continuous intention to use E-HRM (Y4), perceived behavioral control (X2) significantly influenced both perceived innovativeness (Y1) and cognitive absorption (Y2), and perceived innovativeness (Y1) significantly influenced both satisfaction (Y3) and continuous intention to use E-HRM (Y4).

• International journal of advanced smart convergence
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• 제10권1호
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• pp.75-81
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• 2021

As the number of connected smart devices and applications increases explosively, the existing orthogonal multiple access (OMA) techniques have become insufficient to accommodate mobile traffic, such as artificial intelligence (AI) and the internet of things (IoT). Fortunately, non-orthogonal multiple access (NOMA) in the fifth generation (5G) mobile networks has been regarded as a promising solution, owing to increased spectral efficiency and massive connectivity. In this paper, we investigate the achievable data rate for non-orthogonal multiple access (NOMA) with negatively-correlated information sources (CIS). For this, based on the linear transformation of independent random variables (RV), we derive the closed-form expressions for the achievable data rates of NOMA with negatively-CIS. Then it is shown that the achievable data rate of the negatively-CIS NOMA increases for the stronger channel user, whereas the achievable data rate of the negatively-CIS NOMA decreases for the weaker channel user, compared to that of the positively-CIS NOMA for the stronger or weaker channel users, respectively. We also show that the sum rate of the negatively-CIS NOMA is larger than that of the positively-CIS NOMA. As a result, the negatively-CIS could be more efficient than the positively-CIS, when we transmit CIS over 5G NOMA networks.

• 한국통신학회논문지
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• 제13권5호
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• pp.379-389
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• 1988

본 논문에서는 통신방의 2-상태 스취칭 실패함수를 구하기 위한 알고리즘과 단섭간 신뢰도 계성방법을 제시하였다. 통신망을 그래프로 모형화하고, 이 그래프에 대한 일련의 행열변환을 함으로서 모든 통신통로를 차단하는 최초컷-\ulcornerV 행열을 구하였으며 최소 컷-\ulcornerV행열로부터 2-상태 스위칭 실패함수를 구하였다. 또한 2-상태 스위칭 실패함수에 확률변수를 대응시켜 통신망의 단점간 신뢰도를 계정하였다. 제안된 알고리즘을 설명하기 위하여 몇가지 예를 보였으며 복잡하고 규모가 큰 망에 대한 단점간 신뢰도를 계정하기 위해서 전산기 프로그램을 제시하였다.

• Journal of Animal Science and Technology
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• 제54권6호
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• pp.463-469
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• 2012

This study utilized a standardization and cluster analysis technique for the selection and classification of beneficial bacteria. A set of synthetic data consisting of 100 individual variables with three characteristics was created for analysis. The three characteristics assigned to each independent variable were designated to have different numeric scales, averages, and standard deviations. The variables were bacterial isolates at random, and the three characteristics were fermentation products, including cell yield, antioxidant activity of culture, and enzyme production. A standardization method utilizing a standard normal distribution equation to record fermentation yields of each isolate was employed to weight their different numeric scales and deviations. Following transformation, the data set was analyzed by cluster analysis. The Manhattan method for dissimilarity matrix construction along with complete linkage technique, an agglomerative method for hierarchical cluster analysis, was employed using statistical computing program R. A total of 100 isolates were classified into groups A, B, and C. In a comparison of the characteristics of each group, all characteristics in groups A and C were higher than those of group B. Isolates displaying higher cell yield were classified as group A, whereas those isolates showing high antioxidant activity and enzyme production were assigned to group C. The results of the cluster analysis can be useful for the classification of numerous isolates and the preparation of an isolation pool using numerical or statistical tools. The present study suggests that a simple technique can be applied to screen and select beneficial microbes using the freely downloadable statistical computing program R.

• 산업기술연구
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• 제3권
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• pp.53-63
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• 1983

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; Pf=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 F3/F2 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. In cases that strength parameters are assumed to be normal variated and beta variated, the relationships between safety factor and the probability of failure are fairly consistent, regardless of the shape of the 3-D shear surface and the slope. 4. As the c-value is increased, the probability of failure for the same safety factor is increased and as the ${\phi}-value$ is increased, the probability of failure for the same safety factor is decreased.