• Korean Journal of Remote Sensing
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• v.21 no.6
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• pp.483-491
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• 2005

SAR signal processing technique has been considered a crucial technical part in order to generate an image from radar signal data and ADD (Agency for Defense Development) has focused on this area for years to develope our own SAR Processor for various SAR systems (Radarsat, ERS, KOMSAR). In this paper, we investigated major techniques related to generation of SAR images and developed ASPR (ADD SAR Processor for Radarsat) practically using the commercial Radarsat-1 radar signal data (RAW). We demonstrated the performance of the ASPR in comparison with the image generated by MDA and Vexcel's SAR Processor (FOCUS).

• 한국전기화학회:학술대회논문집
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• 2002.07a
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• pp.251-258
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• 2002

[ $Ni-10wt.\%Cr$ ] green sheet를 불활성분위기로 $900^{\circ}C$까지 승온시킨 다음 부분산화$(P_{H2}/P_{H2O}=10^{-2})$후 $1100^{\circ}C$에서 3시간 환원처리를 시키는 소결공정으로 Ni-Cr 고용체 기지 주변에 작은 $Cr_2O_3$ 알갱이가 고르게 분포하는 anode(Anode Sintered in Partial oxidation - Reduction atmosphere; ASPR)를 제조하였으며, creep 변형률이 $2.8\%$로서 미세구조에 따른 creep 특성의 비교를 위해 기존의 환원분위기에서만 소결시킨 anode(Anode Sintered in Reduction atmosphere only; ASR)의 $11\%$보다 우수한 creep 저항성을 나타내었다. $Cr_2O_3$ 알갱이가 분산된 미세구조른 부분산화 시 Cr과 Ni의 산화속도 및 확산속도의 차이로 인해 형성되는 것으로 사료되며, creep 전${\cdot}$후 ASPR 시편의 SEM 및 기공률 분석결과 매우 안정적으로 그 형상 및 구조를 유지하고 있음을 확인할 수 있었다. 또한 ASPR 시편의 전기전도도는 약 $15\times10^6\;S/m$로서 기존 ASR 시편의 전기전도도와 유사함을 알 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.48.4-48
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• 2002

1) A method to realize active vibration control using SAC and acceleration type sensor is proposed from the viewpoint of practical application. 2) The use of acceleration type sensor makes it easy to satisfy ASPR condition in applying SAC system and to implement sensor in practical mechanical system. 3) Results were confirmed through numerical simulation of 1 DOF vibration system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9B
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• pp.793-805
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• 2003

In OBS (Optical Burst Switching) networks which decouple the burst from its header, the fault of a fiber link can lead to the failure of all the light-path that traverses the fiber. Because each light-path is expected to operate at a rate of a few Gbps by using WDM (Wavelength Division Multiplexing) technology, any failure may lead to large data loss. Therefore, an efficient recovery scheme must be provided. In this paper, we analyze network utilization and BCP (Burst Control Packet) loss rate according to each link failure by applying the conventional restoration schemes in OBS networks. And through these simulation results, an ASPR scheme is proposed improve the fault management scheme in terms of recovery time and throughput. Finally, We compare the performance of our proposed scheme with that of the conventional one with respect to burst loss rate, resource utilization and throughput by OPNET simulations.

• Transactions of The Korea Fluid Power Systems Society
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• v.8 no.2
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• pp.23-28
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• 2011

This paper investigates the motion control of a hydraulic motor-load system using the Simple Adaptive Control (SAC) method. The plant transfer function has been modelled mathematically. The open-loop responses have been obtained experimentally in order to identify the design parameters of transfer function. The hydraulic motor-load system has been modelled using the 3D CAD and imbedded in the hydraulic circuit simulation program to verify the overall performance. The experimental results confirm that the SAC method gives a good tracking performance compared to the PID control.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.8
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• pp.936-941
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• 2011

This paper deals with the issue of motion control of a single rod cylinder-load system using simple adaptive control (SAC) method. Prior to controller design, the experiment of open-loop response has been performed. Based on it, design parameters of transfer function are obtained and used for controller design. The effect of parallel feedforward compensator has been investigated by computer simulation, suppressing the oscillatory motion. Through experiments it is conformed that the SAC method gives good tracking performance compared to the PD control method.

• 유공압시스템학회:학술대회논문집
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• 2010.06a
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• pp.81-85
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• 2010

This paper deals with the issue of motion control of a single rod cylinder-load system using simple adaptive control (SAC) method. Prior to controller design, the experiment of open-loop response has been performed. Based on it, design parameters of transfer function are obtained. The effect of parallel feedforward compensator has been investigated by computer simulation, suppressing the oscillatory motion. Through experiments it is conformed that the SAC method gives good tracking performance compared to the PD control method.

• Journal of Korean Society for Quality Management
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• v.48 no.2
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• pp.297-307
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• 2020

Purpose: The purpose of this study is to analyze the factors that affect ammunition performance by applying data mining techniques to the Ammunition Stockpile Reliability Program (ASRP) data of the 155mm propelling charge. Methods: The ASRP data from 1999 to 2017 have been utilized. Logistic regression and decision tree analysis were used to investigate the factors that affect performance of ammunition. The performance evaluation of each model was conducted through comparison with an artificial neural networks(ANN) model. Results: The results of this study are as follows; logistic regression and the decision tree analysis showed that major defect rate of visual inspection is the most significant factor. Also, muzzle velocity by base charge and muzzle velocity by increment charge are also among the significant factors affecting the performance of 155mm propelling charge. To validate the logistic regression and decision tree models, their classification accuracies have been compared with the results of an ANN model. The results indicate that the logistic regression and decision tree models show sufficient performance which conforms the validity of the models. Conclusion: The main contribution of this paper is that, to our best knowledge, it is the first attempt at identifying the significant factors of ASPR data by using data mining techniques. The approaches suggested in the paper could also be extended to other types ammunition data.