http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
자동표적인식 성능 향상을 위한 전자광학/적외선 영상 잡음 판별 기법
조준후(Jun Hoo Cho),강창호(Chang Ho Kang),박찬국(Chan Gook Park) 제어로봇시스템학회 2017 제어·로봇·시스템학회 논문지 Vol.23 No.2
We propose a method to identify image noise type for an automatic target recognition system. In previous studies, kurtosis and skewness of image noise have been considered during identification. However, these two features vary according to each image, whereby the identification accuracy is not convincing. In order to maintain the performance of noise identification according to various images and intensities, we carried out a logistic regression analysis and designed a model-based image noise identification method using random sample consensus (RANSAC). It was confirmed that the proposed algorithm identifies 3 types of image noise according to 50 different images and 4 different noise levels.
프로베니우스 놈 기반 이중 인자 적응 필터를 이용한 INS/GPS 초강결합 기법
최영권(Yeongkwon Choe),강창호(Chang Ho Kang),김선영(Sun Young Kim),박찬국(Chan Gook Park) 제어로봇시스템학회 2018 제어·로봇·시스템학회 논문지 Vol.24 No.8
This paper presents a deeply coupled INS/GPS system that uses a Frobenius norm-based adaptive filter for countering signal interferences. A deeply coupled INS/GPS system integrates an INS (inertial navigation system) and a receiver based on vector tracking loops. Vector tracking loops track signals from satellites based on navigation solutions, which provides great immunity to signal interferences and the high dynamics of a receiver. However, dependence on the navigation solution means that if the navigation solution is wrongly estimated once, the entire tracking loop can fail. Therefore, navigation filters for measurement noise must be properly handled to avoid tracking failures when signal interferences exist. This paper applies a Frobenius norm-based adaptive filter. Whereas conventional Frobenius norm-based adaptive filters use only one adaptive factor, this paper expands the filters to use two adaptive factors to deal with INS/GPS deep integration. To verify the performance of expanded filters, an experiment is conducted with a commercial GPS noise jammer. The test results exhibit better performance compared to conventional methods.
항공 영상 융합의 성능 향상을 위한 적응 가이디드 필터
김선영(Sun Young Kim),강창호(Chang Ho Kang),박찬국(Chan Gook Park) 한국항공우주학회 2016 韓國航空宇宙學會誌 Vol.44 No.5
본 논문에서는 최적의 항공 영상 융합을 위하여 적응 가이디드 필터 기반 알고리즘을 제안하였다. 제안한 적응 가이디드 필터는 가이디드 필터 설계 요소 중에서 정규화 파라미터 값을 입력된 영상 특성에 따라서 조절하고 PSNR (peak signal to noise ratio)을 미리 정해둔 값으로 유지한다. 제안한 방법은 입력 영상의 특성에 관계없이 미리 정한 PSNR을 유지하는 범위 내에서 잡음을 제거하므로 최적의 영상 융합 성능의 결과를 가져올 수 있다. 필터 성능은 시뮬레이션을 통해 검증하였고, 기존에 많이 사용되고 있는 영상융합 품질 파라미터를 이용하여 분석하였다. In this paper, an aviation image fusion method is proposed for creating an informative fused image through gray scale images within noise. The proposed method is based on an adaptive guided filter which adjusts regulation parameter of the filter based on peak signal noise ratio (PSNR) in order to behave as an edge-preserving filtering property. Simulation results demonstrate that the proposed method preserves the edge information of the input image and reduces the noise effect while maintaining designed PSNR.
적응 페이딩 칼만 필터를 이용한 기준국 기반의 램프 형태 GNSS 기만신호 검출 알고리즘
김선영(Sun Young Kim),강창호(Chang Ho Kang),박찬국(Chan Gook Park) 제어로봇시스템학회 2015 제어·로봇·시스템학회 논문지 Vol.21 No.3
In this paper, a GNSS interference detection algorithm based on an adaptive fading Kalman filter is proposed to detect a spoofing signal which is one of the threatening GNSS intentional interferences. To detect and mitigate the spoofing signal, the fading factor of the filter is used as a detection parameter. For simulation, the effect of the spoofing signal is modeled by the ramp type bias error of the pseudorange to emulate a smart spoofer and the change of the fading factor value according to ramp type bias error is quantitatively analyzed. In addition, the detection threshold is established to detect the spoofing signal by analyzing the change of the error covariance and the effect of spoofing is mitigated by controlling the Kalman gain of the filter. To verify the performance analysis of the proposed algorithm, various simulations are implemented. Through the results of simulations, we confirmed that the proposed algorithm works well.
비전형적인 위치에 생긴 중추신경계 Langerhans 조직구 증식증: 증례 보고
김응엽,이재규,김찬교,이창현,강창호,정필욱,Kim, E. Yup,Lee, Jae-Kyu,Kim, Chan-Kyo,Lee, Chang-Hyun,Kang, Chang-Ho,Chung, Phil-Wook 대한영상의학회 2003 대한영상의학회지 Vol.48 No.3
중추신경계 Langerhans 조직구 증식증은 시상하부-뇌하수체 축을 주로 침범하고 자기공명 영상(MRI)T1 강조 영상에서 흔히 뇌하수체 후엽의 밝은 점이 보이지 않고, 누두부 비후 또 는 시상하부에 종괴가 보이는 것으로 알려져 있다. 저자들은 뇌하수체 후엽의 밝은 점이 보이지 않고 시상하부와 누두부에 이상 소견 없이 소뇌와 대뇌기저핵을 침범한 중추신경계 Langerhans 조직구 증식증 1예를 보고하고자 한다. Langerhans cell histiocytosis of the central nervous system (CNS) usually involves the hypothalamic-pituitary axis, and T1-weighted MR images normally demonstrate infundibular thickening and/or a mass lesion in the hypothalamus and the absence of a posterior pituitary "bright spot". We recently encountered a case of CNS Langerhans cell histiocytosis with no posterior pituitary "bright spot"and with lesions involving the cerebellum and basal ganglia but not the hypothalamic-pituitary axis.
다중 선형 칼만 노치 필터 기반의 다중 진동 주파수 제거 기법
김선영(Sun Young Kim),강창호(Chang Ho Kang),박찬국(Chan Gook Park) 제어로봇시스템학회 2018 제어·로봇·시스템학회 논문지 Vol.24 No.2
This paper presents a multiple linear Kalman notch filter (MLKNF)-based mitigation method for eliminating multiple vibration frequencies in the received signal. The MLKNF is the extension version of the linear Kalman notch filter (LKNF) whose state variables are multiple vibrations in the time domain. The transfer function of the LKNF is similar to that of the second order notch filter in steady state but the LKNF has some advantages compared to the conventional notch filter. The LKNF is an efficient tool for mitigating the interference frequency because the filter has a faster convergence rate and smaller error than the conventional notch filter. The MLKNF’s performance is evaluated by Matlab-based simulation. Simulation results show that three vibration frequencies are simultaneously mitigated with small errors compared to the conventional notch filter.