• 대한전자공학회논문지SP
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• 제41권6호
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• pp.253-260
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• 2004

본 논문에서는 정수 웨이블릿 변환(Integer Wavelet Transform)과 선형 예측(Linear Prediction)을 이용한 Hybrid 무손실 오디오 부호화 알고리즘을 제안하였다. 제안된 부호화기는 입력된 신호를 적당한 프레임으로 분할 후, 정수 웨이블릿 변환과 정수 예측기를 사용하여 입력된 오디오 신호내의 상관관계(Correlation)를 제거하였다. 그리고 신호내의 상관이 제거된 신호를 엔트로피 부호화(Entropy Coding) 하였다. 엔트로피 부호화기로는 정수 입력원의 특성에 따라 최적의 압축 효율을 갖는 옵션을 선택적으로 처리하는 Adaptive Golomb-Rice 부호화기법을 이용하였다. 제안된 부호화 방식은 모든 연산을 정수 연산으로 가능케 하므로 기존의 실수를 사용하는 연산과 비교하여 연산 속도의 개선과 시스템의 복잡성을 낮추어 고속처리 및 저전력화가 가능하다. 또한 각 프레임은 독립적으로 부호화되고, 부호화된 데이터는 프레임헤더와 바이트 단위로 정렬이 되도록 데이터 포맷을 설계하여, 압축 부호화된 데이터의 이동, 찾기, 편집이 편리하도록 하였다.

• International Journal of Internet, Broadcasting and Communication
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• 제12권2호
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• pp.1-7
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• 2020

The secure access the lighting, Heating, ventilation, and air conditioning (HVAC), fire safety, and security control boxes of building facilities is the primary objective of future smart buildings. This paper proposes an authorized user access to the electrical, lighting, fire safety, and security control boxes in the smart building, by using color grid coded optical camera communication (OCC) with face recognition Technologies. The existing CCTV subsystem can be used as the face recognition security subsystem for the proposed approach. At the same time a smart device attached camera can used as an OCC receiver of color grid code for user access authentication data sent by the control boxes to proceed authorization. This proposed approach allows increasing an authorization control reliability and highly secured authentication on accessing building facility infrastructure. The result of color grid code sequence received by the unauthorized person and his face identification allows getting good results in security and gaining effectiveness of accessing building facility infrastructure. The proposed concept uses the encoded user access authentication information through control box monitor and the smart device application which detect and decode the color grid coded informations combinations and then send user through the smart building network to building management system for authentication verification in combination with the facial features that gives a high protection level. The proposed concept is implemented on testbed model and experiment results verified for the secured user authentication in real-time.

• 한국정보전자통신기술학회논문지
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• 제11권4호
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• pp.319-324
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• 2018

본 논문에서는 ISO/IEC 10646과 멀티바이트 코드 세트간의 변환 시스템을 설계하고 구현한다. 65,000 문자의 코드를 제공하는 UCS 세트는 128 문자의 코드 용량을 제공하는 ASCII 코드의 제한성을 해결하고, 전세계 언어의 표현, 전송, 교환, 처리, 저장 및 입출력을 단일 코드 페이지에서 적용하며, 다국어 소프트웨어 개발시 코드 변환을 단순화시킴으로써 프로그램의 코드 수정을 위한 시간과 비용을 효율적으로 절감하게 한다. 따라서 UCS 코드 시스템과 ASCII 및 EBCDIC 코드 시스템들이 혼용되어 사용되는 환경에서는 상호 시스템간의 코드 변환 방법은 시스템 마이그레이션시 제공되어야 하는 중요한 고려 사항이다. 본 논문의 코드 변환 유틸리티는 UCS와 IBM 호스트 코드간의 매핑 테이블을 포함하고 있으며 제안된 코드 변환 알고리즘을 시스템에서 구현하였다. 제안된 코드 변환 프로그램은 실제 시스템 환경에서 성공적으로 구동하였음을 검증하였고, UCS와 멀티바이트 코드 시스템간의 마이그레이션시 가이드라인으로 제공될 수 있다.

• Journal of Biosystems Engineering
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• 제17권1호
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• pp.65-78
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• 1992

When using a computer vision system for a measurement, the geometrically distorted input image usually restricts the site and size of the measuring window. A geometrically distorted image caused by the image sensing and processing hardware degrades the accuracy of the visual measurement and prohibits the arbitrary selection of the measuring scope. Therefore, an image calibration is inevitable to improve the measuring accuracy. A calibration process is usually done via four steps such as measurement, modeling, parameter estimation, and compensation. In this paper, the efficient error calibration technique of a geometrically distorted input image was developed using a neural network. After calibrating a unit pixel, the distorted image was compensated by training CMLAN(Cerebellar Model Linear Associator Network) without modeling the behavior of any system element. The input/output training pairs for the network was obtained by processing the image of the devised sampled pattern. The generalization property of the network successfully compensates the distortion errors of the untrained arbitrary pixel points on the image space. The error convergence of the trained network with respect to the network control parameters were also presented. The compensated image through the network was then post processed using a simple DDA(Digital Differential Analyzer) to avoid the pixel disconnectivity. The compensation effect was verified using known sized geometric primitives. A way to extract directly a real scaled geometric quantity of the object from the 8-directional chain coding was also devised and coded. Since the developed calibration algorithm does not require any knowledge of modeling system elements and estimating parameters, it can be applied simply to any image processing system. Furthermore, it efficiently enhances the measurement accuracy and allows the arbitrary sizing and locating of the measuring window. The applied and developed algorithms were coded as a menu driven way using MS-C language Ver. 6.0, PC VISION PLUS library functions, and VGA graphic functions.

• 대한전자공학회논문지SP
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• 제42권5호
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• pp.73-78
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• 2005

DCT기반 압축기법에 의해 부호화된 영상은 양자화에 의한 여러 가지 화질열화요소가 포함되는데, 그중 인간 시각에 민감한 대비 왜곡은 화질 열화 요인으로서 가장 중요한 요인이다. 특히 저비트율에서 부호화된 영상의 경우 많은 고주파 성분이 양자화에 의하여 손실되기 때문에 좋은 화질을 갖는 영상을 복원할 수 없을 것이다. 따라서 본 논문에서는 대비 왜곡을 포함하고 있는 부호화된 영상에 대해 DCT영역에서 대비를 개선시키는 새로운 알고리즘을 제안한다. 대비왜곡은 외곽선 주변에서 심하게 나타나기 때문에 DCT블록의 외곽선 포함 정도를 판단하여 문턱치보다 큰 블록은 다시 4개의 부블록으로 나누어 적용된다. 제안되는 방법은 모든 연산이 DCT 영역에서 수행되기 때문에 실시간 처리 응용분야에 적용될 수 있을 것이다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.215-219
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• 2003

In this paper, we generate a trajectory minimized the energy gait of a biped robot for walking a staircase using genetic algorithms and apply to the computed torque controller for the stable dynamic biped locomotion. In the saggital plane, a 6 degree of freedom biped robot that model consists of seven links is used. In order to minimize the total energy efficiency, the Real-Coded Genetic Algorithm (RCGA) is used. Operators of genetic algorithms are composed of a reproduction, crossover and mutation. In order to approximate the walking gait, the each joint angle is defined as a 4-th order polynomial of which coefficients are chromosomes. Constraints are divided into equality and inequality. Firstly, equality constraints consist of position conditions at the end of stride period and each joint angle and angular velocity condition for periodic walking. On the other hand, inequality constraints include the knee joint conditions, the zero moment point conditions for the x-direction and the tip conditions of swing leg during the period of a stride for walking a staircase.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1521-1524
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• 2003

In this paper, we propose a "Distance Correlation Selection operator (DCS)" as a new selection operator. For Genetic Algorithm (GA), many improvements have been proposed. The MGG (Minimal Generation Gap) model proposed by Satoh et.al. shows good performance. The MGG model has all advantages of conventional models and the ability of avoiding the premature convergence and suppressing the evolutionary stagnation. The proposed method is an extension of selection operator in the original MGG model. Generally, GA has two types of selection operators, one is "selection for reproduction", and the other is "selection for survival"; the former is for crossover and the latter is the individuals which survive to the next generation. The proposed method is an extension of the former. The proposed method utilizes distance information between individuals. From this extension, the proposed method aims to expand a search area and improve ability to search solution. The performance of the proposed method is examined with several standard test functions. The experimental results show good performance better than the original MGG model.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1249-1253
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• 2003

License plate recognition is very important in an automobile society. This is because, since plate detection accuracy has large influence on subsequent number recognition, it is very important. However, it is very difficult to do it, because a background and a body color of cars are similar to that of the license plate. In this paper, we propose a new thresholds determination method in the various background by using the real-coded genetic algorithm (RGA). By using RGA, the most likely plate colors are decided under various lighting conditions. First, the average brightness Y values of images are calculated. Next, relationship between the Y value and the most likely plate color thresholds (upper and lower bounds)are obtained by RGA. The relationship between thresholds decided from RGA and brightness average is aproximate by using the recursive least squares (RLS) algorithm. In the case of plate detection, thresholds are decided from these functions.

• Journal of Advanced Marine Engineering and Technology
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• 제25권1호
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• pp.124-130
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• 2001

This paper presents a methodology on automation of a trailer type vehicle which consists of two parts: a tractor and a trailer. Backward moving and parking control is very important to automate this type of vehicle. It is difficult to control the motion such a trailer vehicle whose dynamics in non-holonomic. Therefore, in this paper, the modeling and parameter estimation of the system using a RCGA(real-coded genetic algorithm) is proposed and a backward path tracking control algorithm is then obtained. The simulation results verify the effectiveness of the proposed method.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2007년도 춘계학술대회 학술발표 논문집 제17권 제1호
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• pp.341-344
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• 2007

본 논문에서는 계층적 공정 경쟁 개념을 병렬 유전자 알고리즘에 적용하여 계층적 공정 경쟁 기반 병렬유전자 알고리즘 (Hierarchical Fair Competition Genetic Algorithm: HFCGA)을 구현하였을 뿐만 아니라 실수코딩 유전자 알고리즘(Real-Coded Genetic Algorithm: RCGA)에서 좋은 성능을 갖는 산술교배(Arithmetic crossover), 수정된 단순교배(modified simple crossover) 그리고 UNDX(unimodal normal distribution crossover)등의 다양한 교배연산자들을 적용, 분석함으로써 개선된 병렬 유전자 알고리즘을 제안하였다. UNDX연산자는 다수의 부모(multiple parents)를 이용하여 부모들의 기하학적 중심(geometric center)에 근접하게 정규분포를 이루며 생성된다. 본 논문은 UNDX를 이용한 HFCGA모델을 구현하고 함수파라미터 최적화 문제에 많이 쓰이는 함수들에 적용시킴으로써 그 성능의 우수성을 증명 한다.