• Communications for Statistical Applications and Methods
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• v.18 no.4
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• pp.467-475
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• 2011

This paper develops the noninformative priors for the stress-strength reliability from one parameter generalized exponential distributions. When this reliability is a parameter of interest, we develop the first, second order matching priors, reference priors in its order of importance in parameters and Jeffreys' prior. We reveal that these probability matching priors are not the alternative coverage probability matching prior or a highest posterior density matching prior, a cumulative distribution function matching prior. In addition, we reveal that the one-at-a-time reference prior and Jeffreys' prior are actually a second order matching prior. We show that the proposed reference prior matches the target coverage probabilities in a frequentist sense through a simulation study and a provided example.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.11
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• pp.506-513
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• 2001

The islanding detection for distributed resources (DR) becomes an important and emerging issue in power system protection since the distributed generator installations are rapidly increasing and most of the installed systems are interconnected with distribution network. In order to avoid the negative impacts from islanding operations of DR on protection, operation and management of distribution system, it is necessary to effectively detect the islanding operations of DR and rapidly disconnect it from distribution network. Generally, it is difficult to detect islanding operation by monitoring only one system parameter This paper presents a new logic based islanding detection method for distributed resources(DR) which are interconnected with distribution network. The proposed method detects the islanding operation by monitoring four system parameter: voltage variation, phase displacement, frequency variation, and the variation of total harmonic distortion(THD) of current; therefore, it effectively detects island operation of DR unit operating in parallel with the distribution network. We also verified the efficiency of the proposed algorithm using the radial distribution network of IEEE 34 bus model.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.325-327
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• 2004

VoIP는 음성 및 데이터 통합 뿐만 아니라 차세대 네트웍 등의 기반이 되는 기술이며, 인터넷전화 / IP Telephony, 화상회의, 메신저 서비스 등 여러 서비스에 활용되고 있다. 이러한 VoIP 서비스 제공시에 가장 중요시되는 부분이 음성품질이며 이를 측정 및 관리하는 기술이 필수적으로 필요하다. 지금까지는 품질측정장비를 가지고 직접 측정하는 것이 전부였으나 본 연구는 IETF의 VoIP 표준 프로토콜인 MGCP중 파라미터 값을 이용하여 ITU-T의 음성품질 기준인 R factor(G.107)를 계산해 내고 중앙에서 모든 단말 및 사용자들의 실제 발생한 통화에 대한 음성품질을 관리할 수 있는 시스템을 설계 및 구현한다.

• Nuclear Engineering and Technology
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• v.35 no.6
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• pp.556-565
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• 2003

A quality assurance safety assessment database, called QUARK (QUality Assurance Program for Radioactive Waste Management in Korea), has been developed to manage both analysis information and parameter database for safety assessment of low- and intermediate-level radioactive waste (LILW) disposal facility in Korea. QUARK is such a tool that serves QA purposes for managing safety assessment information properly and securely. In QUARK, the information is organized and linked to maximize the integrity of information and traceability. QUARK provides guidance to conduct safety assessment analysis, from scenario generation to result analysis, and provides a window to inspect and trace previous safety assessment analysis and parameter values. QUARK also provides default database for safety assessment staff who construct input data files using SAGE(Safety Assessment Groundwater Evaluation), a safety assessment computer code.

• Journal of the Korean Data and Information Science Society
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• v.21 no.5
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• pp.935-944
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• 2010

In this paper, we develop the noninformative priors for the reliability in a stress-strength model where a strength X and a stress Y have independent exponential distributions with different scale parameters and a common location parameter. We derive the reference priors and prove the propriety of joint posterior distribution under the general prior including the reference priors. Through the simulation study, we show that the proposed reference priors match the target coverage probabilities in a frequentist sense.

• The Korean Journal of Ecology
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• v.23 no.6
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• pp.435-438
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• 2000

Diameter distributions describe forest stand structure information. Prediction equations for percentiles of diameter distribution and parameter recovery procedures for the Weibull distribution function based on four percentile equations were applied to develop prediction system of even-aged slash pine stand structure development in terms of the number of stems per diameter class changes. Four percentiles of the cumulative diameter distribution were predicted as a function of stand characteristics. The predicted diameter distributions were tested against the observed diameter distributions using the Kolmogorov-Smirnov two sample test at the ${\alpha}$=0.05 level. Statistically, no significant differences were detected based on the data from 236 evaluation data sets. This stand level diameter distribution prediction system will be useful in slash pine stand structure modeling and in updating forest inventories for the long-term forest management planning.

• Korean Journal of Computational Design and Engineering
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• v.12 no.6
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• pp.405-412
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• 2007

It's difficult for manufacturers to derive a new design from the demands of consumers as quickly as possible and a designer carries out design operation using insufficient resources in initial design. To carry out initial design process efficiently for an excavator front group, it is necessary for a designer to manage lots of parameter with an existing knowledge or with in-house know-how and develop function module that calculates working range and excavator force. By doing so, it will bring up the optimized values of parameters based on the DOE in the early design stage. In this paper, a new approach to improve the process with optimized parameters is proposed to reduce a product development time of the excavator front design.

• Journal of the Korean Data and Information Science Society
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• v.25 no.3
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• pp.623-632
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• 2014

We shall consider the estimation for the parameter and the right tail probability in a general exponential distribution. We also shall consider the estimation of the reliability P(X < Y ) and the skewness trends of the density function of the ratio X=(X+Y) for two independent general exponential variables each having different shape parameters and known scale parameter. We then shall consider the estimation of the failure rate average and the hazard function for a general exponential variable having the density function with the unknown shape and known scale parameters, and for a bivariate density induced by the general exponential density.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.195-202
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• 2017

We can sometimes find instability against numerical solutions in nonlinear regression. All iterative procedures in nonlinear regression require initial parameter values to be selected. Poor starting values may result in convergence to an unwanted stationary point of the error sum of squares surface. Starting values can sometimes cause the chaos effect in the nonlinear regression model. We can find the chaos phenomena with the convergence plot of starting values in the parameter space.

• Advances in nano research
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• v.13 no.1
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• pp.63-75
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• 2022

The nonlinear dynamic behavior of a nonuniform small-scale nonlocal beam is investigated in this work. The nanobeam is theoretically modeled using the nonlocal Eringen theory, as well as a few of Von-nonlinear Kármán's theories and the classical beam theory. The Hamilton principle extracts partial differential equations (PDE) of an axially functionally graded (AFG) nano-scale beam consisting of SUS304 and Si₃N₄ throughout its length, and an elastic Winkler-Pasternak substrate supports the tapered AFG nanobeam. The beam thickness is a function of beam length, and it constantly varies throughout the length of the beam. The numerical solution strategy employs an iteration methodology connected with the generalized differential quadratic method (GDQM) to calculate the nonlinear outcomes. The nonlinear numerical results are presented in detail to examine the impact of various parameters such as nonlinear amplitude, nonlocal parameter, the component of the elastic foundation, rate of cross-section change, and volume fraction parameter on the linear and nonlinear free vibration characteristics of AFG nanobeam.