• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.368-370
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• 2001

There are various shapes such as square, rectangular, L, and T type in the grounding systems of substations. IEEE St-d suggests the formula considering the characteristics of the various grounding systems but the final value can not be taken, and them the analysis of complicated computer program for obtaining the more accurate value is needed. In his paper, by using CDEGS(Current, Distribution, Electromagnetic and Soil Structure Analysis) the estimated functions derives form the modification coefficient for each of various types above mentioned. The mesh voltage expected can be obtained without the conventional expensive program using compensating methods that multiply IEEE formula by the estimated function.

• 한국컴퓨터정보학회논문지
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• 제20권12호
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• pp.61-66
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• 2015

In this paper, we draw a security assessment by analyzing possible vulnerabilities of the designated PC service which is supposed for strengthening security of current online identification methods that provide various areas such as the online banking and a game and so on. There is a difference between the designated PC service and online identification methods. Online identification methods authenticate an user by the user's private information or the user's knowledge-based information, though the designated PC service authenticates a hardware-based unique information of the user's PC. For this reason, high task significance services employ with online identification methods and the designated PC service for improving security multiply. Nevertheless, the security assessment of the designated PC service has been absent and possible vulnerabilities of the designated PC service are counterfeiter and falsification when the hardware-based unique-information is extracted on the user's PC and sent an authentication server. Therefore, in this paper, we analyze possible vulnerabilities of the designated PC service and draw the security assessment.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (1)
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• pp.508-510
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• 1998

기존의 절차 지향 프로그램을 이해하고 유지.보수하기 위해서는 많은 비용이 필요하다. 이러한 절차 지향 프로그램에서 객체/클래스를 추출한다면 프로그램을 이해하고 유지.보수하는데 많은 비용을 절감할 수 있을 뿐 아니라, 객체 지향 프로그램으로 변환하는데 많은 도움이 된다. 본 논문에서는 객체/클래스를 추출하기 위한 절차와 구조를 제시하였다. 객체/클래스 추출기는 Clustering Engine, Stochastic Refinement and Decision Engine, Domain Modelling와 Comparison and Intergration Engine의 4부분으로 구성된다. 이러한 과정을 거치면서 기존의 연구 방법과는 다르게 가중치 주는 기준, 다중 객체 후보, 통계적 방법으로의 정재와 결정, 요구사항의 의미적 관점에 기초한 방법을 사용하였다.

• 한국안전학회지
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• 제26권6호
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• pp.20-25
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• 2011

This study presents on the fire hazard analysis of communication cable in buildings. In order to analyze fire hazards for communication cable IEC 60332-1, UL 94 and cone calorimeter test are conducted. The number of cable used to experiment is 10 communication cable which are generally applied to data communication in buildings. The results show that 9 cables do meet the performance requirement of IEC 60332-1 and 8 cables are V-0 classification. IEC 60332-1 and UL 94 test are inadequate for fire hazard classification. The various parameters obtained by cone calorimeter test such as HRR, peak HRR, smoke production rate and so on. Also it is able to evaluate multiply fire hazard for communication cable with cone calorimeter test results.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.93-94
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• 2008

양이온 금속원소(Al)와 음이온 할로겐 원소(F) 및 수소를 다중 도핑한 ZnO 박막을 rf 마그네트론 스퍼터를 이용하여 코닝 글라스에 증착하여 도핑량과 진공중에서의 열처리에 따른 전기적 및 광학적 특성에 대하여 고찰하였다. 양이온이 할로겐 및 수소와 동시에 도핑될 시, 금속이온의 농도가 낮은 것이 TCO 박막의 전기적 특성 향상에 유리하게 작용하는 것으로 나타났으며, 동일한 F 함량에 대하여는 수소가 증가할수록 박막의 전기적 특성이 향상되는 것으로 나타났다. 그러나 열처리에 따른 F와 H의 거동은 반대로 나타나서, 최적의 상대적인 도핑 조성이 있음을 시사하였고, 36.2 $cm^2$/Vs의 높은 흘 이동도와 $2.9\times10^{-4}{\Omega}cm$의 낮은 비저항을 가지는 ZnO계 박막의 제조가 가능하였다.

• 전기학회논문지
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• 제65권3호
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• pp.445-451
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• 2016

General fuse elements of solution for fast acting operation characteristics made using silver or silver alloy, those are not able to dominate cost competition to the advanced global leaders that have not only high technology but competitive price. In this study, the method that compose the fuse elements manufactured solution of fast acting operation characteristics by using precision multi-layer thin film plating and helical cutting process from low-priced copper metal. Furthermore, in order to move rated current line of fuse due to the heat loses, the manufacture construction method of fixed resistor is introduced, and then Ni-P plating layer and Sn plating layer are introduced multiply for controling fine opening time characteristics. So this study can establish the high productive and low-priced production method.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.49-50
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• 2019

In the case of High-rise buildings, it has a problem by stack effect that rise of vertical height. Especially in case of fire, it need to the consideration of stack effect that it has bigger than general. Therefore in this study, we used to the Contamw and FDS simulation for analysis of stack effect and pressure distribution characteristic in fire. As a result the Contamw simulation shows the pressure distribution by stack effect in general high-rise buildings. However, in case of fire, the height of the neutral plane is lowered and stack effect is larger. Therefore, it is necessary to multiply analyze the temperature distribution and the stack effect in fire.

• Structural Engineering and Mechanics
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• 제57권2호
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• pp.221-238
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• 2016

One of the objectives of this study is to implement the direct calculation of the torsional moment of inertia for non-circular cross-sections, which is based on the St. Venant torsion formulation and the finite element method. Recently the proposed method provides a unique calculation of the torsional rigidity of simply and multiply connected cross-sections. Next, free vibration analyses of cylindrical and non-cylindrical helices with non-circular cross-sections are solved by a curved two-nodded mixed finite element based on the Timoshenko beam theory. Some thin-thick closed or open sections are handled and the natural frequencies of cylindrical and non-cylindrical helices are compared with the literature and the commercial finite element program SAP2000.

• 대한임베디드공학회논문지
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• 제4권1호
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• pp.1-8
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• 2009

This paper proposes a 24-bit floating point multiply and accumulate(MAC) unit that can be used in geometry transformation process in 3D graphics. The MAC unit is composed of floating point multiplier and floating point accumulator. When separate multiplier and accumulator are used, matrix calculation, used in the transformation process, can't use continuous accumulation values. In the proposed MAC unit the accumulator can get continuous input from the multiplier and the calculation time is reduced. The MAC unit uses about 4,300 gates and can be operated at 150 MHz frequency.

• 한국광학회지
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• 제24권2호
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• pp.92-98
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• 2013

회전검광자 방식의 타원계 구조에 기초하여 두꺼운 막들 내부에서 일어나는 다중반사에 인한 빛의 세기를 결맞지 않도록 중첩함으로써 결맞음길이보다 두꺼운 막 두 개가 다층박막시료 위에 있을 때 적용되는 타원상수 표현들을 유도하였다. 유도된 표현들을 커버유리와 공기층 아래에 있는 산화규소 박막이 코팅되어 있는 시료의 타원법 분석에 적용하여 그 유용성을 확인하였다.