• Journal of Korean Institute of Industrial Engineers
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• v.27 no.4
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• pp.374-378
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• 2001

We present a discrete-time version of the distributional Little's law, of which the continuous-time version is well known. Then we extend it to the queue in which two or more customers may depart at the same time. As a demonstration, we apply this law to various discrete-time queues such as the standard Geom/G/1 queue, the Geom/G/1 queue with vacations, the multi-server Geom/D/c queue, and the bulk-service Geom/$G^b$/1 queue. As a result, we obtain the probability generating functions of the numbers in system/queue and the waiting times in system/queue for those queues.

• Communications of the Korean Mathematical Society
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• v.11 no.2
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• pp.503-514
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• 1996

We consider non-constant coefficient elliptic equations of the type -div(a \bigtriangledown u) = f$, and employ the P-version of the finite element method as a numerical method for the approximate solutions. To compute the integrals in the variational form of the discrete problem we need the numerical quadrature rule scheme. In practice the integrations are seldom computed exactly. In this paper, we give an $L_2(\Omega)$-error estimate of $\Vert u = \tilde{u}_p \Vert_{0,omega}$ in comparison with $\Vert u = \tilde{u}_p \Vert_{1,omega}$, under numerical quadrature rules which are used for calculating the integrations in each of the stiffness matrix and the load vector.

• Journal of the Korean Mathematical Society
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• v.41 no.2
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• pp.345-368
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• 2004

A preconditioning algorithm is developed in this paper for the iterative solution of the linear system of equations resulting from the p-version boundary element approximation of the three dimensional integral equation with hypersingular operators. The preconditioner is derived by first making the nodal and side basis functions locally orthogonal to the element internal bases, and then by decoupling the nodal and side bases from the internal bases. Its implementation consists of solving a global problem on the wire-basket and a series of local problems defined on a single element. Moreover, the condition number of the preconditioned system is shown to be of order $O((1＋ln/p)^{7})$. This technique can be applied to discretization with triangular elements and with general basis functions.

• Journal of the Korean Home Economics Association
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• v.48 no.10
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• pp.133-141
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• 2010

The purpose of this study was to investigate the construct validity of the Penn Interactive Peer Play Scale on the parent version. The participants of this study were 231 children in the Seoul and Gyeonggi provincial areas. The instruments included the 32-item exploratory PIPPS (Choi & Shin, 2008), and the Preschool Behavior Questionnaire (PBQ; Park, 1992). The data were analyzed by descriptive statistics, factor analysis, Pearson's r and Cronbach ${\alpha}$. The results were as follows. First, the PIPPPS on the parent version was validated with supporting three factors: Play Disruption, Play Disconnection and Play Interaction with 30 items. The sub-factors of the PIPPS were related with those of the PBQ as criterion measurements. The reliability coefficients of the sub-factors of the PIPPS were ranged from .78 to .82.

• The Korean Journal of Applied Statistics
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• v.7 no.2
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• pp.213-224
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• 1994

A diagnostic method useful for detecting outliers in testing the equality of two covariance metrics is developed using the influence curve approach. This method is easily generalized to more than two covariance matrices. A sample version for the influence measure of detecting outliers is considered based on the empirical distribution functions. The sample version includes as its component terms the well-known test statistic for detecting one outlier at a time introduced by Wilks and its generalization to the two-group case.

• Journal of the Korean Society for Library and Information Science
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• v.34 no.1
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• pp.17-37
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• 2000

This study aims to provide a guide to the selection and purchase of a good CD-ROM encyclopedia by establishing evaluation criteria for CD-ROM encyclopedia. This study first divided evaluation criteria into the following rune categories: reviews available, print version, availability of trial disc, hardware requirements and ease of software installation, database contents, retrieval software, standalone/network version, standard/deluxe version, costs. Next, it suggested evaluation points and items in detail under each category.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.110.2-110.2
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• 2011

Nishikida et al. (2006) presented the first far-ultraviolet (FUV) em${\lambda}$ission-line images of the Vela supernova remnant (SNR) obtained with FIMS/SPEAR instrument. Those include C III ${\lambda}$977, O VI ${\lambda}{\lambda}$1032, 1038, Si IV+O IV] ${\lambda}{\lambda}$1393, 1403 (un-resolved), C IV ${\lambda}{\lambda}$1548, 1551 emission-line images. As a following work, we re-constructed these emission-line images using the new-version processed FIMS/SPEAR data. Additionally, we made N IV] ${\lambda}$1486, He II ${\lambda}$1640.5, O III] ${\lambda}{\lambda}$1661, 1666 emission-line images. The new-version images cover the whole region of the Vela SNR and show more resolved features than the old-version. We compare these FUV emission-line images with other wavelength (X-ray, optical, etc.) images obtained in previous studies.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10b
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• pp.760-762
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• 2003

HL7(Health Level 7)은 보건의료 분야에서 ANSI에서 승인한 SDO(Standards Developing Organization)들 중의 하나이다. 대부분의 SDO들은 약제. 의료 장비 이미지, 보험 처리 등과 같은 보건의료 분야에서의 표준을 만든다. HL7의 영역은 진료와 병원 행정적인 부분이다. HL7에서는 Version2.3, Version2.4, Version3.0 등을 포함해 Data Model. Arden Syntax, CCOW(Common Context Object Workgroup) CDA(Clinical Document Architecture) 등의 표준을 만들어 나간다. 본 논문에서는 이 표준들 중 CCOW에 대해 알아보고. 기존 Agent System에 좀 더 지능적이고 자율적인 CCOW 서비스를 제공하는 방안을 알아본다.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.2
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• pp.78-86
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• 2020

The environmental tests are one of the key branches of the reliability tests. The purpose of the high/low environmental test of KT-1 Export Version Trainer is not only based on meeting the compliance of the reliability, customer satisfaction, but also for the expansion of its export. Amongst many existing environmental tests, the high and low temperature tests are considered as the two most important tests. The tests are considered and tailored to the high and low temperature methods of MIL-STD-810H. This paper proposes the tailoring processes and the results of High/Low temperature conditions, test procedures, and test profiles for the aircraft. Additionally, this paper is described by considering the view of MIL-STD-810H.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.591-598
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• 1997

The COBRA/RELAPS code, an integrated version of the COBRA-TF and RELAP5/MOD3 codes, has been developed for the realistic simulations of complicated, multi-dimensional, two-phase, thermal-hydraulic system transients in light water reactors. Recently, KAERA developed an unified version of the COBRA/RELAP5 code, which can run in serial mode on both workstations and personal computers. This paper provides the brief overview of the code integration scheme, the recent code modifications, the developmental assessments, and the future development plan.