• Journal of the military operations research society of Korea
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• v.25 no.1
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• pp.75-86
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• 1999

The selection criteria of an Authorized Stockage List (ASL) in the Army is based on Army Regulation(AR)409. However, the current selection method of ASL is not considered in cost, weight and volume of repair parts. This paper is focused on developing for a new selection model taking account of cost, weight and volume of repair parts. Goal programming is utilized in order to consider weighted priorities. Different units of cost, and volume are normalized for using weighing value. Real data of a field division are applied to the model. Results of the new selection model are more reduced in cost, weight and volume than those of the previous method.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.10a
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• pp.45-50
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• 1990

This study develops practical models and methods for the assessment of safety and capacity rating of existing P.C. girder bridges based on the reliability methods. One of the main objectives of the study is to propose a practical but realistic limit state model for safety assessment and LRFR rating criteria, which explicitly incorporates the degree of deterioration and damage as well as actual condition of P.C. girder bridges in terms of the damage factor and the response ratio. The damage factor proposed in the paper is defined as the ratio of the current estimated stiffness to the intact base-line stiffness of a member. Based on the observation and the results of applications to existing bridges, it may be concluded that the proposed methods for the assessment and capacity rating models, which explicitly account for the uncertainties and effects of degree of deterioration or damage, provide more realistic and consistent safety-assessment and capacity rating.

• Structural Engineering and Mechanics
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• v.27 no.1
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• pp.63-75
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• 2007

The code provisions on lap splices are critically assessed in the light of 203 beams without transverse reinforcement and 278 beams with transverse reinforcement. For comparison, the provisions given in the ACI 318, Eurocode 2, and TS 500 Codes are considered. The ACI Committee 408 recommended provision and a new proposal are also taken into account throughout the assessment. The comparison with real beam tests where the splice region was subjected to constant moment indicates that current provisions in the Codes do not agree acceptably with test results. The steel stress prediction graphs calculated by means of the Code provisions show high scatter and remain unsafe especially for test data without transverse reinforcement. Both the recent recommended provision by ACI Committee 408 and a new design expression proposed by the author have much less scatter with fewer unsafe predictions. The simplified design provision proposed by ACI Committee 408 does not yield similar results to that of the advanced design provision proposed by the same committee and therefore it could conveniently be replaced with the simpler equation proposed by the author.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.338-341
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• 2005

Recently there are increasing needs for Internet and various kinds of contents. These traffics for various contents need more amount of data to provide high-quality information and require various QoS depending on the characteristics of contents. However, current Internet service supports BE (Best Effort) service only, therefore IntServ (Integrated Service) scheme and DiffSserv (Differentiated Service) scheme are represented to support QoS in IP layer. This paper describes new scheme that provides QoS taking into account the traffic characteristics over Mobile IPv6 network based on IEEE 802.11e by decreasing signal process time using traffic class of DiffServ and evaluates the performance through computer simulation.

• Proceedings of the KIEE Conference
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• summer
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• pp.1025-1027
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• 2004

Recently, the Single phase SRM has been researched and developed in many appliances with various types. This paper presents a theoretical representation of the phase inductance of a single phase SRM, as function of position and current, taking into account the non-linearity of the magnetic circuit. The method is based on the Fourier series expansion. the theoretical expressions for the calculation of instantaneous phase inductance, flux linkage, coenergy and electromagnetic torque as a function of rotor position and winding currents are derived. And it is compared with the results of the finite element analysis.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.9
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• pp.448-453
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• 2003

In this paper the controlled closing algorithm of the circuit breaker for isolated capacitor banks is proposed. The characteristics of circuit breakers such as RDDS(rate of decrease of dielectric strength) and a mechanical operating tolerance should be also taken into account to locate contact touch instants around voltage zero. The analysis results on the voltages across circuit breaker terminals upon closing operation play an important roles to describe the suggested method. The simulations carried out in order to verify the performance of this method show that the closing instants obtained from the proposed method provide a good suppression effect on the closing transients for both single and back-to-back capacitor banks.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.1
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• pp.1-6
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• 2002

This paper proposes an advanced reclosing scheme to improve power quality in power distribution systems. When a fault occurs in distribution system, the proposed schema determines the number of reclosing shots and its intervals according to the magnitude of fault current. Thus, an advanced reclosing scheme takes account of the power quality problem in customer\`s and the damage in electric facilities. To verify the effectiveness of the proposed scheme, a numerical simulation that calculates various indices to consider the reliability and the other effects on electric facility, in carried out with actual field data.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.63-66
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• 2001

Photovoltaic System does military exploit that use heliometer light and is clearness source of energy. Photovoltatic System is no noise, shock among is several Substitute energy and after establishment maintenance having simple special quality, is applied in many fields. However, while Photovoltatic System is having these advantage, but react sensitively in effect of Photovoltaic scanning Quantity, temperature change etc.. surrounding environment, when did not satisfy condition, express indefinite output price. Consider voltage$\cdot$current output measurement value and temperature revision calculation by temperature change of existing photovoltaic system and change of output price of when did Simulation analyzed comparison.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.1
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• pp.88-95
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• 2014

The infrared, flame detector uses to detect fire situation from the characteristics of fire sources radiant energy. But it is able to malfunction on account of susceptible to interference of various surrounding waves. This paper is designed 6 independent PCB-boards to minimize the closed loops of siginal circuit. Also considering the interaction of electric and magnetic fields, this paper is designed protecting circuit of current and voltage output to reduced electromagnetic interference. And this paper is improving electromagnetic susceptibility by ferrite bid, capacitor filter and grounding circuits.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.70-71
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• 2007

Analyzing pentacene field effect transistors (FETs) with Au source and drain electrodes as Maxwell-Wagner effect elements, electron and hole injection from the Au electrodes into the FET channel were examined using current-voltage (I-V), capacitance-voltage (C-V) and optical second harmonic generation (SHG) measurements. Based on these results, a mechanism of the hole and electron injection into pentacene from the Au electrodes and subsequently recombination mechanism with light-emitting in the pentacene layer are discussed, with taking into account the presence of trapped charges.