• Korean Management Science Review
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• v.27 no.3
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• pp.99-115
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• 2010

We classified quality management practices of manufacturing companies into 'Infra' factor and 'Process' factor which were introduced based on existing literatures and previous studies related to quality management. It was our first objective to confirm its conformance in Korean manufacturing industry, and to examine the two factors effect positively on production performance. Moreover, we tried to examine whether JIT and workforce management have an moderate effect on 'Infra and Process factors-performance' relationship, using moderate regression. As the result of empirical study on nationwide manufacturing companies, we had the results that the classification between Infra factor and Process factor in quality management practices was valid in Korean manufacturing companies, and that the two factors gave performances positive effect. Moreover, our secondary analysis showed that JIT had an positive moderate effect on the Infra factor while workforce management on the Process factor. With these results, we have an interpretation that manufacturing companies which aim to enhance short term performances have to concentrate their effort and investment on Process factor and, on the other hand, ones which aims to improve long term performances on Infra factor.

• Steel and Composite Structures
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• v.28 no.5
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• pp.629-639
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• 2018

In this paper, the vibroacoustic responses of baffled laminated composite sandwich flat panel structure under the influence of harmonic excitation are studied numerically using a novel higher-order coupled finite-boundary element model. A numerical scheme for the vibrating plate has been developed in the frame work of the higher-order mid-plane kinematics and the eigen frequencies are obtained by employing suitable finite element steps. The acoustic responses are then computed by solving the Helmholtz wave equation using boundary element method coupled with the structural finite elements. The proposed scheme has been implemented via an own MATLAB base code to compute the desired responses. The validity of the present model is established from the conformance of the current natural frequencies and the radiated sound power with the available benchmark solutions. The model is further utilized to scrutinize the influence of core-to-face thickness ratio, modular ratio, lamination scheme and the support condition on the sound radiation characteristics of the vibrating sandwich flats panel. It can be concluded that the present scheme is not only accurate but also efficient and simple in providing solutions of the coupled vibroacoustic response of laminated composite sandwich plates.

• The Journal of the Acoustical Society of Korea
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• v.31 no.4
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• pp.225-234
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• 2012

The anechoic chamber is essential tool to measure the various acoustic parameters with high precision. The chamber provides the climate controlled indoor environments but requires the dedicated room at a great cost in order to isolate and absorb sound field. Provided the purpose of the chamber is specific to the experiments of sound localization, the performance requirements excluding free field can be alleviated for cost effective solution. This paper designs low cost and profile anechoic chamber based on acoustic pyramids and evaluates the performance specified by the Annex of ISO 3745. Data analysis is employed to measure the free and hemi-free field performance over five straight paths for working areas and four paths for non-working areas. The identical two measurement campaigns were conducted for free and hemi-free field chamber which is easily interchangeable by simple labor in this chamber design. In the working area with conventional speaker, the results of these analyses demonstrate that lab-designed anechoic chamber is in conformance with ISO 3745 for 250 Hz - 16 kHz one-third octave band at free field chamber and for 1 kHz - 16 kHz one-third octave band at hemi-free field chamber.

• Journal of the Korean Society of Systems Engineering
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• v.11 no.1
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• pp.1-7
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• 2015

The purpose of this paper is to present the results of reengineering of the YGN 3&4 (Yonggwang Nuclear Power Plant, Units 3&4) SDS (Safety Depressurization System) retrofit design and to make recommendations for the improvement in design and design procedure implementing the Systems Engineering (SE) process. YGN 3&4 is a basic model for OPR1000 (the Korean standard 1000 MWe plant). The basic model, herein, represents the reference plant for the OPR1000 development. In the middle of the YGN 3&4 construction, the Korean Nuclear Regulatory Body requested a retrofit of this plant with a means to rapidly depressurize the plant in conformance with a severe accident mitigation requirement. For the reengineering of the SDS in YGN 3&4, V-model and functional and physical architectures have been developed. A SE decision making method has been used for the selection of SDS valves. Finally, recommendations have been made to improve OPR1000 design for the improved operation and enhanced safety.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.5
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• pp.1157-1162
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• 2015

This paper is the design and implementation to the 4x4 MIMO algorithm based on OFDM, and presented how to verify the implemented result. Algorithm applied the MRVD and QRM-MLD. Matlab and Simulink are used to design channel presumption & MIMO algorithm by Floating-point and Fixed-point model. After then implement VHDL using Modelsim. Performance of algorithm is checked by comparing Simulink model, Modelsim simulation, ISE ChipScope with the result measured by oscilloscope. This method is useful to verify an algorithm with uncompleted system. Conformance between the result of ChipScope and the result of oscilloscope is confirmed, it could be applied on the Backhaul system.

• The Transactions of the Korea Information Processing Society
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• v.4 no.5
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• pp.1327-1336
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• 1997

Test generation from the communication protocol specified in I/OFSM protocol is based on the asumption that the specification S and implemenataiton I are storngly, connected,minmal and deterministic.In this paper,we identify why these asumptions are necessary for minimal test cases genration from I/OFSM protocol speci-fication,and we propose a graph Rewriting System and its application to the specification I/OFSM for verifying its storng cinnectivity.We prove that the suggested algorithm is more dffcient thah the traditional strongly connected compoment find algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.361-371
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• 2010

To vitalize the terrestrial DMB market, we introduce a personalized DMB(PDMB) service model based on metadata, especially DMB ECG XML standardized by TTA, under the convergence of broadcasting and telecommunications. Also we introduce the personalized DMB service system developed to validate the conformance of DMB ECG XML standard and the usefulness of DMB ECG service. The personalized DMB service system is described in details from the authoring stage to the consumption stage of the contents. The results of experimental tests for the personalized DMB service system are also introduced in this paper. We finally address the possibility of making successful personalized DMB services in mobile multimedia broadcasting market.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.56-57
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• 2006

IEC61850은 변전소 자동화 시스템에 관한 국제 표준이다. IEC61850-10에서는 시스템을 구성하고 있는 각 기기들이 IEC61850 국제표준을 준수하고 기기들간의 상호운영성을 입증하기 위해 적합성 검사를 정의한다. 하지만 IEC61850-10에서 기술된 내용은 무엇을 검사할 것인지에 대해 추상적 방식으로 서술하고 있고 어떻게 검사하는지에 대해 구체적 방법의 제시는 부족하다. 이에 대해 UCA IUG(International Users Group)는 품질 보증 프로그램(QAP)을 운영한다. QAP는 IEC61850에 따른 검사절차에 대해 명시할 뿐만 아니라 그룹에 참여한 모든 사람들에게 이득을 가져다준다. 본 논문에서는 이러한 QAP에 대해 소개한다.

• The Journal of Korean Association of Computer Education
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• v.5 no.4
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• pp.31-42
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• 2002

In this paper, We set up the development methodology of communication protocols as well as the concrete design concept concerning for how to define and use the PDU, SDU, SAP, and service primitives using SDL, which is recommended by ITU-T, and other international standard languages such as ASN.l, MSC, and TTCN. This methodology covers the SDL design of extended lures protocol, a well known protocol example, insertion of ASN.1 message for transportation of bit string, generation of MSC for validation of design specification, generation of test cases using TTCN from validation, and performance of conformance test.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.313-320
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• 2003

The efficient and well organized database is essential for the management of information in every industrial field. In this study, a practical and effective database which can handle 3-D information of steel bridges is built on the basis of a STEP-based data model. The data model of steel bridge information is classified into geometric and non-geometric part and the design information is represented by linking geometric information and life cycle supported non-geometric information. Especially, the shape information is represented by boundary representation method, which is one of the representative methods of solid model information. In this study, ISO/STEP(STandard for the Exchange of product model data) AP203(configuration controlled design) EXPRESS schema is used to represent the shape information of steel bridge. The syntax of EXPRESS schema of developed data model is verified by NIST Expresso - is a tool for parsing and compiling EXPRESS schema. Also, this study verifies the conformance of the data model by applying to the real data of Hannam bridge. Therefore, the constructed database using STEP-based data model of steel bridges can be used effectively in the concurrent engineering point of view with transferring and sharing steel bridge information.