• International Journal of Automotive Technology
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• 제8권2호
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• pp.225-232
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• 2007

A tooth profile modification for loaded gears is used to avoid a tooth impact. Since a tooth profile error causes amplification of the cumbersome whine noise in automotive gear transmissions, an optimal quantity of tooth profile modifications must be obtained for good performance in the vibration sense. In this paper, a tooth profile modification curve considering profile manufacturing errors and elastic deformation of the gear tooth is formulated; in addition, transmission errors of the gear system with modified teeth are verified. The equivalent excitation due to transmission errors is formulated. For experimental evaluation of the transmission error, the transmission error for a simple gear system was measured by two rotational laser vibrometers. Finally, we perform a comparative analysis between the calculated and measured responses to the excitations due to the transmission error to verify the practicability of the application to automotive transmissions.

• 교통기술과정책
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• 제9권5호
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• pp.68-75
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• 2012

• 한국당과학회:학술대회논문집
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• 한국당과학회 2006년도 제1회 연례학술대회
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• pp.24-24
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• 2006

• 한국지능시스템학회논문지
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• 제3권1호
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• pp.97-101
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• 1993

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1305-1311
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• 2014

The nickel oxide, the most widely used cathode material for the molten carbonate fuel cell (MCFC), has several disadvantages including NiO dissolution, poor mechanical strength, and corrosion phenomena during MCFC operation. The surface modification of NiO with lanthanum maintains the advantages, such as performance and stability, and suppresses the disadvantages of NiO cathode because the modification results in the formation of $LaNiO_3$ phase which has high conductivity, stability, and catalytic activity. As a result, La-modified NiO cathode shows low NiO dissolution, high degree of lithiation, and mechanical strength, and high cell performance and catalytic activity in comparison with the pristine NiO. These enhanced physico-chemical and electrochemical properties and the durability in marine environment allow MCFC to marine application as a auxiliary propulsion system.

• 정보보호학회논문지
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• 제25권6호
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• pp.1449-1453
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• 2015

IoT환경에서는 소프트웨어의 안전성과 무결성이 중요하다. 하지만 IoT의 제한된 성능 때문에 소프트웨어 검증에 음영지역이 발생한다. 제한된 제어 변조 공격은 이러한 음영지역을 목표로, 대상 프로그램의 핵심 분기문을 변조하여 동작을 조작한다. 본 논문에서는 이러한 공격에 대응하여 프로그램에 marker를 직접 주입하고 확인함으로써 공격을 탐지하는 효율적인 기법을 제안한다.

• 디지털콘텐츠학회 논문지
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• 제11권2호
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• pp.135-144
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• 2010

의무기록은 의료행위에 대한 매우 중요한 기록으로 임의로 변경되지 말아야 한다. 현존하는 의무기록은 모두 변경될 수 있는 여지가 있다. 정보기술의 발달로 전자의무기록이 점차 널리 사용되게 되었다. 전자의무기록을 사용함에 따라 암호학적 기반을 이용하여 의무기록 변경을 방지할 수 기법을 사용할 수 있다. 본 논문에서는 연결해쉬, 전자서명, 전자공증 등의 암호학적 기법을 이용하여 의무기록 변경을 방지할 수 있는 기법을 제안하고 프로토타입을 통하여 수행을 분석한다. 제안된 기법은 적은 추가비용으로 의무기록 변경을 현실적으로 불가능하도록 한다.

• 소음진동
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• 제5권4호
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• pp.555-563
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• 1995

This paper proposes the method of antiresonance frequency analysis of multi-input multi-output system. The structural dynamic modification techniques by antiresonance frequency analysis are also applied to reduce the undertest at specimen attachment points on the fixture in environmental vibration test, which is resulted from the inconsistency of antiresonance frequencies at any specified points. Several computer simulations show that the proposed method can remove the undertest problem which is not removed in conventional vibration test control. And the effectiveness of the method is verified with the impact hammer excitation of aluminium fixture model.

• 한국식생활문화학회지
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• 제14권5호
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• pp.477-485
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• 1999

This study was conducted to improve the functional properties of soybean protein isolate by dimethylglutarylation and acetylation. Amino acid composition and solubility of modified soybean protein by dimethylglutarylation were not changed, but lysine and trypsin inhibitor activity was decreased an isoelectric point was moved from pH5 to pH4 as a result of modification. Emulsification capacity and stability, foaming capacity and thermal stability were increased by the modification. In that 91% dimethylglutarylated protein did not coagulate when heating at $100^{\circ}C$ for 20 min. while its foaming stability was decreased. Whereas specific gravity was decreased by the modification of the soybean protein, relative viscosity and whiteness were improved. Generally, dimethylglutarylation produced more conformational changes in protein system than did in acetylation.

• 한국분말재료학회지
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• 제6권1호
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• pp.36-41
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• 1999

The present work has attempted to investigate the dependence of Cu infiltration kinetics on in-situ structure modification of W powder skeleton in W-Cu system. In-situ structure modification of W skeleton by addition of 0.3wt%Ni-P eutectic alloy was designed to proceed during heat-up of the W compact for Cu infiltration process. It was found that the Ni-P added W skeleton underwent remarkable stucture change only during heating-up. its structure was composed of large necks of W particles above 0.5 in the ratio of neck to particle size and smooth pore channels. The infiltration experiment showed that the infiltration kinetics for the W-Ni-P followed well the linear relationship of h vs. $t^{1/2}$ the rate constant K of which was in good agreement with the theoretical value. On the other hand, in case of the pure W skeleton a lower K value by 20% than the theoretical one was obatined. Such discrepancy is discussed in terms of skeleton structure induced infiltration mechanics.