• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.486-488
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• 1987

Studine the characteristic or C.T.I affectine on the tracking failure when interface active materials are diffused into the phenolic resin. we conclude as follow: 1) As the density of $NH_4Cl$ increase the quality or sludge increase the value of C.T.I decreases. 2) The materal of ion absorption can make the period of sludge metallic matal generation delay more than times and the value of C.T.I increase. 3) By addition of interface active material that makes forming period delay, the starting voltage of corona blackdown id delayed and the value of C.T.I is increased.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.4
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• pp.202-206
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• 2006

In this paper, an auto detection method of stator winding fault of small induction motor is suggested. The Park's vector pattern which is obtained from 3-phase current signal by d-q transforming, is very good to detect winding fault. Comparing the Park's vector pattern of testing motor with its of healthy motor, the Park's vector pattern of fault motor is became an ellipse and the asymmetry is increased by the winding fault series. So for detecting the dis-symmetry, id-filtered function, Min-value, and Max-value are suggested for auto detecting. Using LabVIEW programing, 3-phase healthy motor and several kind of winding fault motors are tested and the test results are shown that the suggested method can gives us a possibility of an auto detecting winding fault.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.407-412
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• 2001

A $Ca^{2+}$_dependent PLA$_2$activity termed rPLA$_2$, was detected in the cytosol of bovine red blood cells (RBCs). The rPLA$_2$was characterized as a similar form to Group IV cPLA$_2$, but different in several column chromatographic profiles including an anion exchange column. To examine whether this rPLA$_2$is different from the well characterized cPLA$_2$, a quinone derivative, BJ50, was developed and tested for the inhibitory effect on the two PLA$_2$enzymes. The rPLA$_2$activity was inhibited by a quinone derivative (BJ50) with ID$_{50}$ of 20 $\mu$M., but had no effect on the cPLA$_2$, suggesting that rPLA$_2$may be a novel type of cytosolic PLA$_2$in RBCs.s.s.

• Journal of information and communication convergence engineering
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• v.3 no.4
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• pp.213-216
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• 2005

Almost all network systems provide an authentication mechanism based on user ID and password. In such system, it is easy to obtain the user password using a sniffer program with illegal eavesdropping. The one-time password and challenge-response method are useful authentication schemes that protect the user passwords against eavesdropping. In client/server environments, the one-time password scheme using time is especially useful because it solves the synchronization problem. It is the stability that is based on Square Root Problem, and we would like to suggest PBI(password Based Identification), enhancing the stability, for all of the well-known attacks by now including Off-line dictionary attack, password file compromise, Server and so on. The PBI is also excellent in the aspect of the performance.

• Management & Information Systems Review
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• v.3
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• pp.399-417
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• 1999

The purpose of this paper id to study the factors influencing MIS user satisfaction. For this purpose. I have reviewed the results of past studies on the performance factor of MIS, and introduced a new model associated with small & Medium Business. On the basis of this model, I have hypothesized that the following variables influence user satisfaction : (gender, age), individual characteristics(user attitude, training for user), managerial characteristic(top management involvement, organizational support) and task characteristics(task structure). There were 195 participants surveyed using questionnaires from 25 different small & medium Business in Pusan. The research model and associated hypotheses were tested by following statistical techniques: reliability test, regression, t-test and ANOVA. The findings of this study are follows; 1. It was found that gender and age are not correlated user satisfaction. 2. Among individual characteristics, only user attitude influence user satisfaction significantly. 3. While organizational supports influence positively user satisfaction, top management involvement do not influence it. 4. Task structure is highly correlated with user satisfaction. In spite of many factors affecting MIS success, this study did not consider all variables affect on user satisfaction. We need integrated model including more various factors.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.4
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• pp.70-80
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• 1996

Experimental results for forced convection condensation of R-22 and R-407C inside 7.5mm ID and 4000mm length of horizontal tubes are presented. The experimental data covered total flow rate from 114.3 to 267.1kg/($m^2$.s) and quality from 0 to 1. The vapor temperature and pressure drop along the tube were measured. The pressure drop for R-407C increased with flow rate similar to that of R-22. The experimental data compared with the available perdictions for pressure drop. Based on the data a prediction method was presented for the calculation of pressure drop of R-22 alternative refrigerants.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.483-491
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• 1997

The purpose of this study id to define the behavior of the girder ledge of precast girder-beam joint in Frame Type Precast Concrete Construction Method. And in behavior, girder ledge is different with bracket, because of longitudinal effective width and longitudinal bending. specif c objectives of this study are followed: $\circled1$ To investigate the effects of concrete compressive strength on the maximum shear strength of girder ledge, $\circled2$ To investigate the effects of the shear-span ratio and effective area on behavior of girder ledge, $\circled3$ To investigate the effects of the types of reinforcement on behavior and maximum shear strength of girder ledge, $\circled4$ To study the applicable possibility of the suggested shear friction formulas to estimating the shear strength of girder ledge.

• Review of KIISC
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• v.13 no.4
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• pp.37-48
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• 2003

응용 수준에서 정보보호를 위한 침입차단시스템(Firewall)과 침입탐지시스템(IDS)은 조직 내의 컴퓨터 서버 보안 대책으로는 그 한계를 갖고 있다. 이에 따라 보안 운영체제(Secure OS)에 관한 필요성이 점차 사회적으로 공감대를 형성하고 있다. 본 고에서는 보안 리눅스 운영체제의 필요성, 기존 리눅스의 보안성, 보안 리눅스의 개발에 따른 요구사항과 개발 방법을 기술한다. 또한 최근 보안 리눅스 연구 동향으로 미국, 일본, 독일 등의 리눅스 보안 연구동향을 살펴보고, 국내 연구기관과 업체의 제품 출시 현황을 살펴본다. 특히 최근 리눅스 커널 2.5.29부터 표준기능으로 포함되고 있는 커널 보안 모듈 방식인 LSM(Linux Security Module)의 기본 구조를 살펴본다. 현재 국내에서 개발하여 보급되고 있는 보안 리눅스 운영체제는 기존 리눅스 커널에 시스템 호출 후킹을 통한 LKM 방식으로 추가적인 접근제어 외에 해킹 차단, 감사 추적, root의 권한 제한, 통합보안관리 등의 추가적 기능을 제공한다. 향후 Firewall, IDS의 한계를 보완하는 서버 보안 대책으로 활발한 보급이 예상된다.

• Review of KIISC
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• v.21 no.4
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• pp.22-31
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• 2011

스마트폰의 성능 향상과 다양한 기능 추가에 따라 스마트폰 사용자의 수는 급증하고 있으며, 모바일 인터넷 활용도가 높아짐에 따라 스마트폰을 통해 PC를 이용한 업무를 대체하는 것이 가능해졌다. 이러한 스마트폰의 성능 진화와 다양한 추가 서비스 제공은 사용자에게 편리함을 주고 있지만, 개인정보 노출, 모바일 악성 코드 등 다양한 위협에 노출될 가능성이 있다. 스마트폰에서의 사용자 인증은 스마트폰 기기를 안전하게 사용하기 위해서 필요한 기본적인 보안 기능이다. 본 논문에서는 스마트폰의 보안 위협 요소와 스마트폰의 사용자 인증 기법에 대해 알아본다. 스마트폰의 전자 지갑 애플리케이션과 해당 애플리케이션을 위해 개발된 사용자 인증 기법에 대해 알아본 후 전자 지갑 애플리케이션을 포함한 스마트폰 사용자 인증 기법의 특정, 장점, 단점 등을 비교 분석한다.

• Transactions on Electrical and Electronic Materials
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• v.5 no.6
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• pp.211-214
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• 2004

We developed a new systematic calibration procedure which was applied to the calibration of the diffusivity, segregation and TED model of the indium impurity. The TED of the indium impurity has been studied using 4 different groups of experimental conditions. Although the indium is susceptible to the TED, the RTA is effective to suppress the TED effect and maintain a steep retrograde profile. Like the boron, the indium shows significant oxidationenhanced diffusion in silicon and has segregation coefficients at the $Si/SiO_2$ interface much less than 1. In contrast, however, the segregation coefficient of indium decreases as the temperature increases. The accuracy of the proposed technique is validated by SIMS data and $0.13 {\mu}m$ device characteristics such as $V_{th}$ and $Id_{sat}$ with errors less than $5 \%$ between simulation and experiment.