• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.4
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• pp.100-105
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• 1997

3-dimensional finite element mehtod (FEM) elecrical field analysis was performed to obtain electric fields on a field emission display (FED) tip in an array form. Because, unlike a single tip structure, there is no azimuthal symmetry for a tip aary, 3D analysis is necessary. To reduce memory requriement the simulatio was performed by applying the neumann boundary condition to the intermediate plane between tips to take the effect of the array on the electric field into account and corresponding current was calculated. To verify our algorithm, comparison between simulation resutls and experimental data from another paper was made and the difference was discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.336-340
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• 2007

본 논문에서는 750kW 풍력발전용 인버터를 개발한 결과와 2년 동안의 현장실증을 통하여 얻어진 경험을 바탕으로 2MW 영구자석형 동기발전기(RMSG, Permanent Magnet Synchronous Generator)의 전력변환을 위한 병렬형 인버터의 시뮬레이션과 이를 통한 설계와 제작 및 기본시험 과정을 소개하고자 한다.

• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.41-42
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• 2017

소셜 네트워크 환경에서 간접 신뢰도는 직접 연결이 존재하지 않는 사용자들의 신뢰도를 평가하는데 유용한 신뢰도 평가 기법이다. 본 논문에서는 사용자간 관심분야와 연결 관계를 고려한 새로운 간접 신뢰도 검출 기법을 제안한다. 제안하는 기법은 사용자의 행위를 분석하여 관심분야를 도출한다. 또한, 멀티 홉으로 연결된 사용자간 신뢰도가 거리에 따라 변동하는 문제를 해결하기 위해 사용자간 연결 관계를 고려하여 간접 신뢰도를 검출한다.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.771-772
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• 2006

IPv6 nodes use the Neighbor Discovery Protocol (NDP) to discover other nodes on the link, to determine their link-layer addresses to find routers, and to maintain reachability information about the paths to active neighbors. If not secured, NDP is vulnerable to various attacks. This document specifies security mechanisms for NDP. Unlike those in the original NDP specifications, these mechanisms do not use IPsec.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.794-797
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• 2004

In this study, tensile adhesive strength(TAS) test was carreid out for evaluated the effects of temperature conditions (-20, -10, 0, 5, 10, 20, 30, $40^{\circ}C$) on the tensile adhesive characteristics about 4 type waterproofing membranes which were commercially used in bridge decks. And, failure appeariences of waterproofing systems in each temperature after TAS test were observed the sawing surfaces of waterproofing systems for whether or not damaged of waterproofing membranes. Also, correction coefficient of TAS with temperature were calculated using 4 type waterproofing membrane. It could be shown that the higher TAS and shear adhesive strength, the lower temperature, regardless of the type of waterproofing membrane. Temperature sensibility of TAS was especially remarkable in epoxy membrane. Failure type was occurred the ductile failure in $30^{\circ}C\;and\;40^{\circ}C$. From these results, it was shown that if ambient temperature above $30^{\circ}C$ maintains for a long time, waterproofing membrane will be deformed by softening. Otherwise, waterproofing membrane in temperature below $20^{\circ}C$ shown that occurred the brittle failure. From the results of visual observation of cutting surface for specimen, the thin waterproofing membranes shown indented by hot aggregate of the asphalt mixtures. Therefore, it could be known that the specification of waterproofing membrane thickness is necessary by waterproofing membrane type. As temperature change varied with pavement depth, the interface temperature was more important than ambient temperature in TAS test. Now, TAS test results were limited only in $-10^{\circ}C\;and\;20^{\circ}C$ temperature, but correction coefficient of TAS by ambient temperature could be used as a solution to deal with this problem.

• Journal of Satellite, Information and Communications
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• v.12 no.1
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• pp.49-53
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• 2017

In this paper we present the combination of location based mobile advertisement services and dynamic digital signage markets has been developing recent days to provide consumer admired visual mobile advertisement on all kind transportation vehicles. In spite of that, the digital signage advertisement content management is still not that easy to manage the content dynamically as well operation is most time consuming to handle the contents dynamically in digital signage business. As location based services is most impactful service in shopping, the location responsive advertisement on vehicle signage will be most desirable mobile advertisement to help people migrate from one place to another place for travel or stay. This paper propose a mobile location responsive digital signage system for vehicles using the GPS and wireless infrastructure integrated with digital signage system. This proposed research use the centralized digital signage system architecture for the mobile advertisement application and this system can be expanded to different vehicles for digital advertisement including buses, trucks, train, air vehicle and any other form of mobile advertising vehicles. Also, this present an effective advertisement recommendation algorithm, by which the advertisement can be selected broadcasted for the right advertisement ventures more effectively as the service requested from advertiser. This paper present the emulated experimental result to evidence the proposed dynamic vehicle signage system performed better than compared with traditional signage random advertising. The emulated result proves that the advertisement recommendation algorithm can effectively works out the targeted key audiences in location responsive region the algorithm evaluated.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.765-768
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• 2008

The prevent methods of Alkali-Silica Reaction (ASR) are studying after the failure cases by ASR were reported in Korea. When ASR failure is causing to the step of maintenance, the available repair methods were rarely studied in the World. In this study, premixed fly ash cement was applied to prevent ASR in the concrete pavement. The ratio of fly ash and cement is 20 percent and 80 percent by weight of total cementious material. The construction performance of premixed fly ash cementious concrete pavement was studied that the application is verify to performance collected data during the constructing in the field. The freeze-thaw test was studied to verify durability of the premixed fly ash cementious material made specimen in the laboratory. The results show that construction performance and durability are well condition in this test section and freeze-thaw test.

• Korean Journal of Logic
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• v.16 no.1
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• pp.87-115
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• 2013

In my previous article "The Uncontested Principle and Wonbae Choi's Objections", I argued that the validity of modus ponens (as a deductive inference) is compatible with the claim that the Uncontested Principle is controversial. In his recent paper "The Uncontested Principle and Modus Ponens", Wonbae Choi criticizes my view again by making the following three claims: First, even though I do not take an inference of the form 'If A then (probably) C. A. $\therefore$ C' as an instance of modus ponens, this form of inference can be taken to be such an instance. Second, there is no grammatical indicator which allows us to distinguish between an indicative conditional based on a deductive inference and an indicative conditional based on an inductive inference, so that inferences based on these conditionals should not be treated as different types of inferences. Third, if we allow an indicative conditional based on an inductive inference, we thereby violate the so-called 'principle of harmony', which any logical concept should preserve. In this paper, I reply that his criticisms are all implausible.

• International Journal of Highway Engineering
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• v.4 no.3 s.13
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• pp.15-23
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• 2002

The waterproofing system's performance is known to show a determing by complex interaction of material factors, design details, and the quality of construction, and the waterproofing integrity of waterproofing membranes is determined by the bond to the deck and the amount of damage to the waterproofing membrane. In this research, the basic properties of waterproofing membranes on market and the tensile adhesive chracteristics of waterproofing systems of concrete bridge deck have also been investigated in the view of the damages frequently reported from job site. For the tensile adhesive strength of sheet waterproofing membranes, the results after asphalt concrete paving tends to increase more than before those. The results of the liquid waterproofing membranes are upside-down, and the more concrete has strength, the more strength of tensile adhesive increase. The ambient temperature of asphalt concrete when application of the waterproofing membrane has considerable influence on the performance of waterproofing system. As described above, waterproofing system can be influenced by several factors. If they are not considered under construction, the overlooking will cause the damages of pavement and waterproofing system after traffic opening.

• Korean Journal of Logic
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• v.21 no.2
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• pp.269-300
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• 2018

In his recent three papers, Joohan Lee defends the following three theses. First, an ordinary term 'believes' is polysemous in that it can refer to three different types of mental attitudes; that is, it can refer to a belief as an involuntary mental disposition, or a pragmatic acceptance as a voluntary mental action, or an epistemic acceptance as a different voluntary mental action. Second, a person's pragmatic acceptance of a proposition is his voluntary mental action which takes it to be true for pragmatic reasons, despite the fact that there is no adequate epistemic evidence for the proposition, whereas a person's epistemic acceptance of a proposition is his voluntary mental action which takes it to be true for epistemic reasons, despite the fact that there is a pragmatic reason to the contrary. Third, mental attitudes to which epistemic norms apply are epistemic acceptances as voluntary mental actions, rather than beliefs as involuntary mental dispositions. If these theses are correct, then they will have important implications for contemporary epistemology. In this paper, however, I argue that Joohan Lee is not successful in defending these theses.