• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2000년도 추계학술대회 논문집
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• pp.113-117
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• 2000

침입 탐지 시스템은 네트워크나 호스트에 대한 오용, 남용, 또는 허가되지 않은 접근을 탐지하는 기능을 갖는 시스템이다. 최근 침입들은 그 종류가 매우 다양화되고, 탐지하기가 매우 어려운 형태로 나타나고 있다. 이러한 침입으로 대표적인 것이 분산 공격과 스텔시 공격(Stealthy Attack)이 있다. 분산 공격은 침입자가 공간적으로 분산되어 이를 탐지하기 어렵게 하는 공격을 말하며, 스텔시 공격은 시간적으로 분산되어 이를 탐지하기 어려운 경우를 말한다. 침입 탐지 시스템의 모델링 및 시뮬레이션을 위해서는 침입 탐지 시스템 모델에 필요한 침입을 제공하고, 침입에 대한 탐지 능력을 평가하기 위한 experimental frame을 디자인 해야한다. 본 연구에서는 분산 공격과 스텔시 공격 기능을 갖는 침입 생성 모델링 방법을 소개하며, 침입 생성을 위해 요구되는 침입 정보 베이스의 역할 및 저장 정보를 소개한다. 또한, 침입에 대한 탐지 능력 평가를 위한 Transducer 모델의 디자인을 소개한다.

• Wind and Structures
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• 제16권5호
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• pp.491-515
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• 2013

Wind pressure characteristics on a double tower high-rise structure, which is disturbed by surrounding buildings, were investigated using large eddy simulation (LES) and 1:300 scale wind tunnel experiments. The computational simulation technique and wind tunnel experimental technique were described in detail initially. Comparisons of computational results with the experimental data have subsequently been carried out to validate the reliability of LES. Comparisons have been performed in detail for the mean and fluctuating pressure coefficients. Detailed explanations of each comparison were given in the paper. To study further on the pressure coefficients on the building surfaces, parametric studies on shape coefficient and spatial correlation were performed and investigated. The numerical and experimental results presented in this paper advance understanding on wind field around buildings and the application of LES and wind tunnel tests.

• 조명전기설비학회논문지
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• 제24권10호
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• pp.130-135
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• 2010

In this paper, the shading ratio about to output the minimum critical power of a photovoltaic panel was determined by experiment and simulation. A 2.475[kW] poly-crystalline photovoltaic panel consisting of 11 modules was used in the experiment and its surface was covered with shading curtains, thus the amount of light incident to the modules were controlled. In order to compare with the experimental results, the experimental circuits were modelled with the CASPOC (power electronics electrical drives simulator) and module parameters were applied to it, by which the minimum critical power was calculated. As a result, the photovoltaic panel was about to generate the power when the 5th shading curtains were removed from the module surface, after then the output power linearly increased by removing the shading curtains. In addition, the CASPOC simulation results were similar to the experimental results in the abrupt decreasing pattern of power.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 전력전자학술대회 논문집
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• pp.383-384
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• 2014

This paper investigates the experimental and simulated time-varying magnetic field generation in a chlor-alkali manufacturing process. 19kA thyristor-based rectifier is modeled and analyzed. The performance is compared and evaluated on the basis of exposure guidelines from ICNIRP. The mechanical structure of current carrying conductor is simplified as an infinite long busbar model and low frequency harmonic contents up to 65kHz are considered. Thyristor rectifier generates a significant amount of low frequency magnetic field harmonic contents both at ac and dc busbar of rectifier infringing the limit of ICNIRP. Along with simulation analysis the experimental measurement of the time-varying magnetic field in ac input busbar, rectifier block, dc load and busbar are presented. The experimental test results partly confirm the simulation results.

• Steel and Composite Structures
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• 제42권4호
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• pp.569-590
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• 2022

This paper presents a combined experimental and numerical study on stainless steel end-plate connections, with an emphasis placed on their ultimate behaviour and rotation capacity. In the experimental phase, six connection specimens made of austenitic and lean duplex stainless steels are tested under monotonic loads. The tests are specifically designed to examine the close-to-failure behaviour of the connections at large deformations. It is observed that the rotation capacity is closely related to fractures of the stainless steel bolts and end-plates. In the numerical phase, an advanced finite element model suitable for fracture simulation is developed. The incorporated constitutive and fracture models are calibrated based on the material tests of stainless steel bolts and plates. The developed finite element model exhibits a satisfactory accuracy in predicting the close-to-failure behaviour of the tested connections. Finally, the moment resistance and rotation capacity of stainless steel end-plate connections are assessed based on the experimental tests and numerical analyses.

• Structural Engineering and Mechanics
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• 제82권6호
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• pp.801-812
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• 2022

To better promote the development of fabricated buildings, this paper studies the seismic behavior of precast concrete beam-column bolted joint under vertical low cyclic loading. The experimental results show that cracks appear in the beam-column joint core area. Meanwhile, the concrete and the grade 5.6 bolts are damaged and deformed, respectively. Specifically, the overall structure of the beam-column joint remains intact, and the bolts have good energy dissipation capacity. Based on the experimental study, a new method of beam-column bolted connection is proposed in simulation analysis. The simulation results show that the bolts deform in the core area of the new beam-column joint, which enhances the concrete shear capacity legitimately and protects the T-end of the beam against shear failure. To summarize, both the experimental joint and the simulated joint prolong the service life by replacing the bolts under the seismic loading. The research results provide a reference for applications of the fabricated beam-column joint.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.179-183
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• 2013

This paper report on experimental results of 5-level inverter by DC divided link voltage. We have alreday reported that DC divided link valtage comes to be able to reduse harmonic of out line voltage. So we tested whether DC divided link voltage can reduce harmonics in experimental setup. This paper shows simulation results and experimental results. And we confirmed that DC divided link voltage can also apply in experimental setup.

• Journal of the Optical Society of Korea
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• 제16권3호
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• pp.215-220
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• 2012

In an earlier work, we proposed the chromatic dispersion monitoring technique of non-return to zero (NRZ) signal based on clock-frequency component (CFC) through numerical simulations. However, we have not yet shown any experimental demonstration or analytic derivation of it. In this paper, we show an experimental demonstration and analytic derivation of the proposed chromatic dispersion monitoring technique. We confirm that the experimental results and the analytic results correspond with the simulation results. We also demonstrate that monitoring range and accuracy can be improved by using a simple clock-extraction method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.803-806
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• 1998

A novel bipolar circuit technique for realizing linear transconductor is described. The proposed circuit has superior linearity and temperature characteristics when compared with the conventional transconductor. The theory of operation is presented and computer simulation results are used to verify theoretical predections. The simulation results show close agreement between predicted behaviours and experimental performances.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.730-735
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• 1992

In this study, heavy loads driving servo control systems, which are composed of electro-hydraulic servo-valve, hydraulic motor/cylinder, gear box and link mechanism, are investigated for implemention. To predict the performances of the systems, modelling and simulation with some nonlinearities are carried out. Simulation results are compared with experimental results.