• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.897-900
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• 2000

Annealing dependencies of the fatigue properties of SrBi$_2$Ta$_2$$O_{9}$ thin films were observed as function of substrate temperature(400-50$0^{\circ}C$) by the rf magnetron sputtering method. With increasing annealing temperature from $600^{\circ}C$ to 85$0^{\circ}C$, flourite phase was crystalized to $650^{\circ}C$ and Bi-layered perovskite phase was crystalized above $700^{\circ}C$. The fatigue characteristics of SBT thin films deposited on Pt/TiO$_2$/SiO$_2$/Si substrate did not change up to 101o switching cycles.s.

• Industrial Engineering and Management Systems
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• v.10 no.4
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• pp.255-263
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• 2011

During the design process of a terminal, the handling capacity of a container yard needs to be evaluated in advance. This study suggests formulas for estimating the expectations and the variances of cycle times for various types of operations of a yard crane. Statistical analysis is used to estimate the expectations and variances. The main focus of this study is to show the impact of interdependencies among handling time elements on the expectation and variance of the cycle times; these interdependencies have not been considered in previous studies. Numerical experiments are done for evaluating the difference in the variance of cycle times and the waiting of trucks between the cases with and without the consideration of interdependencies.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.6
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• pp.401-415
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• 1989

A simple but accurate analytical model for the lateral channel electric field in gate-offset structured Lightly Doped Drain MOSFET has been developed. Our model assumes Gaussian doping profile, rather than simple uniform doping, for the lightly doped region and our model can be applied to LDD structures where the junction depth of LDD is not identical to the heavily doped drain. The validity of our model has been proved by comparing our analytical results with two dimensional device simulations. Due to its simplicity, our model gives a better understanding of the mechanisms involved in reducing the electric field in the LDD MOSFET. The model shows clearly the dependencies of the lateral channel electric field on the drain and gate bias conditions and process, design parameters. Advantages of our analytical model over costly 2-D device simulations is to identify the effects of various parameters, such as oxide thickness, junction depth, gate/drain bias, the length and doping concentration of the lightly doped region, on the peak electric field that causes hot-electron pohenomena, individually. Our model can also find the optimum doping concentration of LDD which minimizes the peak electric field and hot-electron effects.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11c
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• pp.1677-1680
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• 2003

RUP(Rational Unified Process)의 Unified Process Model 에는 Use Case Model, Analysis Model, Design Model, Deployrnent Model, Implementation model, Test Model의 6가지 모델이 있다. 이 모델들은 다음단계의 모델에 대한 일관성 및 의존성을 가진다. 한 모델에서 발생되는 요소들은 전, 후 단계에서 다른 모델들과 Trace Dependencies 를 갖는다. 이러한 의존적인 관계들은 각각의 요소들 사이의 진행, 기록 관계를 나타낸다. 그러나 대부분의 시스템은 이러한 관계 및 의존성 없이 설계되어져 전체적인 일관성을 이루지 못 하였다. 본 논문에서는 이러한 관계를 유지 하면서 사용자의 요구사항에 일관성 있는 Use Case 모델을 설계하고자 한다. 따라서 본 논문에서는 대학 종합정보시스템 구축의 일부분인 구매관리 시스템을 분석하여 컴포넌트 시스템 모델을 제시한다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.395-397
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• 2003

서비스거부공격(DoS)은 공격의 목표가 되는 호스트에 악의적인 패킷을 단지 하나만 보냄으로써 공격이 이루어 질 수 없다. 그렇기 때문에 침입탐지시스템에서는 패킷에 대한 일련의 순차성을 알아냄으로써 연속적인 패킷을 보내는 DoS 공격으로서의 침입을 탐지해 내는 것이 가능하다. 본 연구에서는 네트워크 패킷에 대한 송신지의 주소와 서비스, 목적지의 주소와 서비스를 이용하여 이벤트를 정의 하였으며. 이렇게 정의된 이벤트를 이용하여 정상적인 상황에서의 이벤트에 대한 순차의존성과 DoS 공격 상황에서의 이벤트에 대한 순차의존성을 알아내었다. 이벤트에 대한 순차의존성을 측정하기 위해서 정상 이벤트가 발생하는 확률을 이용하였으며. 더 나아가서는 정보이론 분야에서의 조건부 엔트로피의 사용도 제안하였다.

• Journal of the Korean Magnetic Resonance Society
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• v.19 no.1
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• pp.18-22
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• 2015

The structural geometry of $[N(CH_3)_4]_2CdCl_4$ in a hexagonal phase is studied by $^1H$ MAS NMR, $^{13}C$ CP/MAS NMR, and $^{14}N$ NMR. The changes in the chemical shifts for $^{13}C$ and $^{14}N$ in the hexagonal phase are explained by the structural geometry. In addition, the temperature dependencies of the spin-lattice relaxation time in the rotating frame $T_{1{\rho}}$ for $^1H$ MAS NMR and $^{13}C$ CP/MAS NMR are measured.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.563-569
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• 2004

The formulas taking into account the fundamental features of a meteoric radio propagation are obtained. Numerical simulation analysis has shown complex space structure of a field. Time behavior of intensity are researched taking into account nonstationary model. It is shown, this behavior essentially depends on parameters of a meteor trail, and that there is large variety of time dependencies of the signal intensity at the single scattering. In particular, at appropriate parameters of a meteor underdense trail it is possible large duration meteor bursts with which usually refer to an overdense meteor propagation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.6
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• pp.450-453
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• 2020

In this study, ZnO:Ga thin films were fabricated on a glass substrate using various Ar flows by an RF magnetron sputter system at room temperature. The dependencies of Ar flow on different properties were investigated. An appropriate control over the Ar flow led to the formation of a high-quality thin film. The ZnO:Ga films were formed as a hexagonal wurtzite structure with high (002) preferential orientation. The films exhibited a typical columnar microstructure and a smooth top face. The average transmittance was 85~89% within the visible area. By decreasing the Ar flow, the sheet resistance was decreased due to an increase in the grain size and a decrease in the root mean square roughness. The lowest sheet resistance of 86 Ω/□ was obtained at room temperature for the 40 sccm Ar flow.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2253-2260
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• 2009

BACnet is an international standard communication protocol especially designed for building automation and control systems. In this paper, a reference model of network management system for BACnet is proposed and its implementation method is introduced. In order to evaluate the feasibility and validity of proposed network management system, it is applied to a real experimental model of BACnet network system. Proposed network management system complies with standard BACnet protocol and its functions are implemented in software without hardware dependencies so that it can be applied not only to newly installed BACnet system but also to already installed BACnet system by software upgrade. The network management system and its implementation method introduced in this paper will help BACnet-based automation system to be managed efficiently and they can be practically applied in real BACnet-based automation systems.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.149-153
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• 2009

Today, the form of competition among companies quickly changes in new paradigm. In the past company activity was performed independently, but now dependently. With global age, that change is essential, the introduction of a system that integrates a series of courses is needed for the success of members. Nevertheless, those change are very slow in construction industry, that causes a lot of loss in project process. Construction industry produce structures with collaboration of other industries. There are difficulties that only one company make it, alone. In this trend, cooperation is essential. but the process of original brings a lot of loss From this perspective, this study will prove dependencies of construction industry. Draw out each factor from industrial cooperation, those analyze correlation with system dynamics. In conclusion, this study performs a basic research about 'Integrated Management System' of construction project.