• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.3
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• pp.311-320
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• 2008

A LIDAR can rapidly generate 3D points by densely sampling the surfaces of targets using laser pulses, which has been efficiently utilized to reconstruct 3D models of the targets automatically. Due to this advantage, LIDARs are increasingly applied to the fields of Defense and Security, for examples, being employed to intelligently guided missiles and manned/unmanned reconnaissance planes. For the prior verification of the LIDAR applicability, this study aims at generating simulated LIDAR data. Here, we derived the sensor equation by modelling the geometric relationships between the LIDAR sub-modules, such as GPS, IMU, LS and the systematic errors associated with them. Based on this equation, we developed a program to generate simulated data with the system parameters, the systematic errors, the flight trajectories and attitudes, and the reference terrain model given. This program had been applied to generating simulated LIDAR data for urban areas. By analyzing these simulated data, we verified the accuracy and usefulness of the simulation. The simulator developed in this study will provide economically various test data required for the development of application algorithms and contribute to the optimal establishment of the flight and system parameters.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2646-2650
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• 2009

This paper describes an anti-ARM technique using multiple decoy antennas. We investigate the radar and decoy antenna signal received at the ARM receiver to verify the effect of decoy antennas. And we develop a simulation program using Matlab for optimum positions of the decoys and the effect of ARM by distance between decoys. We suggest optimum positions and distance between decoys based on our simulation results.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.520-521
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• 2010

본 논문은 군사용 미사일의 조립 후 성능 검증을 위한 Missile Assembly Test System(MATS)용 IPMSM의 위치 제어 방법을 구현하였다. 이를 위하여 슬라이딩 모드 제어기와 PI 제어기를 Membership 함수를 사용하여 혼합한 개선된 위치제어 알고리즘을 제안하였다. 오버슈트가 없고, 외란에 대하여 강인하게 운전 궤적을 추정하는 특성이 뛰어난 슬라이딩 모드 제어의 장점과, 빠른 제어 응답성과 정상상태에서 리플이 적은 PI제어를 적절하게 혼합하였고, 이를 시뮬레이션을 통하여 IPMSM의 위치제어 성능을 검증하였다.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.4
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• pp.39-45
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• 1995

본 논문은 복수 집중질량을 갖고 제어 종동력을 받는 자유 Timoshenko보의 동적 안정성에 관한 것으로, 비행중의 미사일이나 로켓의 연료탱크, Payload등의 기계장치부를 복수의 집중질량으로 간주하여 이러한 항공우주 구조물들이 추진력인 종동력을 받을때에 대한 계의 동적 안정성을 판별한다. 수학적 모델에 대한 운동방정식은 확장된 해밀톤 원리를 이용한 유한요소법에 의해 유도되며, 복수 부가질량의 위치 및 크기변화, 센서의 위치 및 게인(gain)의 변화에 따른 계의 안정성 지도(stability maps)를 보여준다. 또한 보의 전단 변형이나 회전관성의 효과 뿐만아니라, 추질력의 방향이 제어되는 경우와 제어되지 않는 경우에 대한 최대 추진력 값이 수치 시뮬레이션을 통해 예측된다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.507-509
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• 2023

본 논문에서는 DSP (Digital Signal Processing)를 이용한 차량용 레이다 수평안정화장치 구동 전략을 제안한다. 지대공 유도 미사일용 차량용 레이다는 전방향으로 일정 속도로 회전하며 감시정찰 임무를 수행한다. 수평안정화장치는 4세트의 수평구동모듈을 이용하여 차량 플랫폼의 수평을 유지하여 레이다의 안정적인 회전을 가능하게 한다. 이를 실시간으로 구현하기 위해 임베디드시스템인 DSP를 적용하여 경사도를 측정하고, 구동모듈에 구동 명령을 인가하여 수평을 유지한다. 수평구동모터는 감속기를 통하여 모터 토크를 증가시켜 수평 안정 동작을 수행한다. 본 논문에서는 수평구동모듈 1세트를 모델링하여 수평안정화장치를 축소 구현한다. 제안하는 구동 전략의 유효성은 시뮬레이션으로 입증한다.

• Journal of the Korea Society for Simulation
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• v.27 no.2
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• pp.115-123
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• 2018

we analyzed simulation of the effectiveness for one or two DIRCM on a helicopter. The survival rate of helicopter followed increase of the deception rate of DIRCM. When the deception rate was over 70% at 100% detection rate, the survival rate was 10~30% when one DIRCM was installed and the survival rate was 70~80% when two DIRCMs were installed. When the detection rate was over 70% at 100% deception rate the survival rate was 10~30% case of one DIRCM was installed. survival rate was 20~30% when two were installed. Survival rate of 70~90% was observed with one DIRCM when the deception rate and detection rate were 100%, and 100% with two DIRCMs.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.367-375
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• 2003

The aim of this study was to investigate the soil physical properties and the traction characteristics of paddy field before tillage by a computer simulation. Soil physical properties, such as soil moisture content, bulk density, soil hardness, and soil texture were measured in the twelve rice production area. Mathematical model based on dimensional analysis which include soil physical properties and vehicle factors was used for the computer simulation. Most of the soil texture of the investigated area was silty loam, loam and silty clay loam. Soil moisture content ranged between 20 and 40% mostly. Soil bulk density was in the range of 1,500 to $1,700kg\;m^{-3}$. Soil hardness ranged between 2 to $12kg\;cm^{-2}$ mostly. Soil hardness incorporates the effects of many soil physical properties such as moisture content, texture and bulk density, and so the range of soil hardness was greater than that of any other physical properties. The predicted net traction was in the range of 70 to 1,500 kgf depending on the area, but it was above 1,000 kgf for most of the investigated area. Thus it was concluded that 50 HP tractor can pull the four row moldboard plow considering the conventional tillage depth and width. But for the soft soil area such as Andong and Namyang, tractor itself may have mobility problem and show high slip during plowing operation.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.681-688
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• 2016

This study assess their quality of radiation on analysis of the spectrum of resolution suggesting IEC 61267 in radiation quality that RQA3, RQA5, RQA7, RQA9 and combination of clinical condition using several quality of radiation. In experiments edge method first, the spatial resolution assessment used image of the additional filter and SID is obtained the IEC 62220-1, spatial resolution and sharpness of the obtained image was evaluated in the MTF value 10%(0.1), MTF value 50%(0.5) using a Matlab program. Second, MCNPX simulation used spatial resolution analysis was radiation quality particle fluence and spectrum analysis in energy. As a result, make use of additional filter, image quality evaluation of SID that RQA3 radiation quality combination qualification is higher spatial resolution and sharpness make unused of additional filter and SID 100cm. RQA7 radiation quality combination qualification is higher that spatial resolution make unused of additional filter and SID 150cm. RQA9 radiation quality combination qualification is higher that spatial resolution and sharpness make used of additional filter and SID 180cm. spectrum analysis of radiation quality by reducing consequent errors occurring in the experiment that error due to the reproducibility of the X-ray tube, occur in an error of correction the detector suggest ideal conditions from spectrum analysis through MCNPX simulation. In conclusion, by suggesting spatial resolution and sharpness of result for various radiation quality, It provide basic data that radiation quality condition and quantitative assessment method for laboratory in clinical using detector evaluation.

• Journal of the Korea Society of Computer and Information
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• v.28 no.9
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• pp.1-8
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• 2023

This paper presents the control strategy of Auto-leveling equipment (ALE) of Multi-function radar (MFR) for vehicle using Embedded System. MFR implements surveillance patrol missions such as surface-to-air missiles and fighters with constant rotation. ALE consists of 4 Auto-leveling modules (ALM) and retains the stability with maintaining level. The gradient of vehicle can be measured and controlled by embedded systems. This paper contributes for improvement the system design with the ALM 1 set modeling. The validity of the modeling is verified using MATLAB/Simulink.

• Journal of the Korea Society for Simulation
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• v.30 no.4
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• pp.9-19
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• 2021

Electronic voting has been recognized as an alternative to complement the limitations of existing paper voting. At the same time, security concerns are being raised. This paper presents a blockchain-based electronic voting and survey system that can guarantee reliability. Our smart contract was created using Solidity on Ethereum which is a blockchain-based distributed computing platform, and the system was implemented in connection with the Javascript based user interface. In addition, in order to protect the personal information of participants, the system is generating hash of the personal data and storing the hash of users for the contract data. Since we exploited different kinds of languages for the system, we derived items of functionality testing and presented the functionality testing result. Moreover, we made use of the Chrome's performance evaluation functionality to see the response time of the blockchain-based system. In addition, we compared the performance with the system which has the same functionality on database. The contribution of this research is design and implementation of blockchain-based electronic voting system and presentation of the functionality and performance simulation result.