• 융합신호처리학회논문지
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• 제4권4호
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• pp.1-6
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• 2003

본 논문에서는, 움직이는 영상을 충돌방지 시스템에 의해 검출한다. 이런 영상의 노이즈는 평균 필터로 제거시킨다. 그리고, 이진 차 영상을 이용하여 움직임이 감지되었을 경우에는 라벨링과 투영방법에 의해 움직임 영역만 정확히 추출하였다. 그 후에 시스템의 추적모드에 의해서 이미지가 천천히 움직일 경우 추적창의 중심은 이전 프레임의 추적창으로부터 이동한다. 그리고, 추적 창은 추적모드와 탐지모드로 나누고, 차 영상 데이터의 대차 상관 값에 의해 결정하였다. 탐지모드는 외란에 의한 에러를 감소하기 위해서 탐지-시간 값의 비교로 추적단계를 계속 진행할 것인지 아닌지를 결정하였다. 이와 같은 움직이는 영상의 탐지와 추적을 시뮬레이션으로 확인하였다.

• 로봇학회논문지
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• 제12권2호
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• pp.173-183
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• 2017

This paper proposes an integrated positioning system to localize a moving object in the shadow-area that exists in the water tank. The new water tank for underwater robots is constructed to evaluate the navigation performance of underwater vehicles. Several sensors are integrated in the water tank to provide the position information of the underwater vehicles. However there are some areas where the vehicle localization becomes very poor since the very limited sensors such as sonar and depth sensors are effective in underwater environment. Also there are many disturbances at sonar data. To reduce these disturbances, an extended Kalman filter has been adopted in this research. To localize the underwater vehicles under the hostile situations, a SVR (Support Vector Regression) has been systematically applied for estimating the position stochastically. To demonstrate the performance of the proposed algorithm (an extended Kalman filter + SVR analysis), a new UI (User Interface) has been developed.

• 한국지능시스템학회논문지
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• 제15권2호
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• pp.163-172
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• 2005

복잡한 환경에서 이동하는 사람의 얼굴영역은 배경과 조명에 의해 확장, 축소 검출되기도 하고 잘못된 영역을 오검출하기도 한다. 본 논문에서는 동영상에서 얼굴을 추적하는데 있어서 확장 혹은 축소검출이나 오검출 문제를 해결하기 위해 블록차 영상과 칼만예측기를 사용하는 방법을 제안한다. 블록차영상은 입력영상을 블록화하여 차영상을 얻는 방법으로 미세한 움직임까지 검출이 가능하여 영상에서 움직임이 작은 경우에도 검출이 가능하게 된다. 검출된 움직임영역에서 얼굴영역은 1차적으로 피부색을 이용하여 검출하며 피부색이 검출되지 않은 경우는 움직임 영역의 경계선을 8이웃화소 창을 이용하여 부호화하고 머리부분의 코드를 갖는 영역을 얼굴영역으로 추정하는 방법을 사용한다. 추정된 얼굴영역을 컬러분할하고 분활된 영역에서 피부색과 가장 가까운 색을 갖는 영역을 얼굴영역으로 판단한다. 얼굴영역은 최외각화소를 포함하는 4각형으로 표시하소 각 정점의 이동을 칼만예측기를 이용하여 추정하고 추정된 위치에서 얼굴영역을 검출하는 방법을 사용한다. 제안하는 방법은 동영상에서 얼굴영역검출의 정확도를 높이고 얼굴영역의 추적에서 얼굴영역검출에 소요되는 시간을 상당부분 감소시키는 효과를 고두게 됨을 실험을 통해 입증하였다.

• 정보학연구
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• 제10권4호
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• pp.27-39
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• 2007

Object tracking in a real time environment is one of challenging subjects in computer vision area during past couple of years. This paper proposes a method of object detection and tracking using adaptive background estimation in real time environment. To obtain a stable and adaptive background, we combine 3-frame differential method and running average single gaussian background model. Using this background model, we can successfully detect moving objects while minimizing false moving objects caused by noise. In the tracking phase, we propose a matching criteria where the weight of position and inner brightness distribution can be controlled by the size of objects. Also, we adopt a Kalman Filter to overcome the occlusion of tracked objects. By experiments, we can successfully detect and track objects in real time environment.

• 한국측량학회지
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• 제37권5호
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• pp.367-377
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• 2019

As an alternative navigation system for the non-GNSS (Global Navigation Satellite System) environment, a new type of DBRN (DataBase Referenced Navigation) which applies both gravity gradient and terrain, and combines filter-based algorithm with profile matching was suggested. To improve the stability of the performance compared to the previous study, both centralized and decentralized EKF (Extended Kalman Filter) were constructed based on gravity gradient and terrain data, and one of filters was selected in a timely manner. Then, the final position of a moving vehicle was determined by combining a position from the filter with the one from a profile matching. In the simulation test, it was found that the overall performance was improved to the 19.957m by combining centralized and decentralized EKF compared to the centralized EKF that of 20.779m. Especially, the divergence of centralized EKF in two trajectories located in the plain area disappeared. In addition, the average horizontal error decreased to the 16.704m by re-determining the final position using both filter-based and profile matching solutions. Of course, not all trajectories generated improved performance but there is not a large difference in terms of their horizontal errors. Among nine trajectories, eights show smaller than 20m and only one has 21.654m error. Thus, it would be concluded that the endemic problem of performance inconsistency in the single geophysical DB or algorithm-based DBRN was resolved because the combination of geophysical data and algorithms determined the position with a consistent level of error.

• 한국지능시스템학회논문지
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• 제14권1호
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• pp.63-68
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• 2004

본 논문은 영상검지기를 이용하여 도로상에서 주행하는 차량의 움직임 추적 시스템에 필요한 탐지방법과 이동궤적을 추적하는 방법을 제안하여 차량의 움직임을 추적하는 시스템을 구현하였다. 도로상에서 주행하는 차량의 움직임을 측정하는 이유는 지능형 교통 시스템의 첨단교통관제에 필요한 정보를 제공한 수 있으며, 기존에 설치되어진 매설식 루프 검지기가 가지는 유지보수의 문제를 해결할 수 있다. 본 논문에서는 양방향 도로에서 주행하는 차량의 물체 탐지를 위하여 차영상 분석법을 기반으로 하였다. 이는 도로의 주변 환경이 빠르게 변화하기 때문에 배경영상을 사용하는 방법은 적합하지 않기 때문이다. 본 논문에서는 칼만필터와 이노베이션을 사용한 가변 탐색영역으로 차량의 이동 궤적을 추적하였다. 가변 탐색영역을 사용한 이유는 기존에 제한된 검색영역을 이용한 방법에서 나타나 질 수 있는 차량의 이동 속도 및 궤적의 변화에 따른 문제를 해결 할 수 있기 때문이다. 실험 결과 제한된 검색영역을 사용하는 방식보다 제안하는 방법이 우수한 성능을 보임을 알 수 있었다.

• 한국군사과학기술학회지
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• 제14권1호
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• pp.114-122
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• 2011

In this paper, we have identified the system instability factors in a bistatic radar system using pulse chasing and considered their effects on the bistatic receiver's MTI(Moving Target Indication) improvement performance. The pulse chasing is a method to efficiently scan a restricted search area within the limited transmitter power and time in a bistatic radar and to track a series of transmitted pulses using the receiver beam which has ideally matched to the pulse propagation rate. In this paper, we have discussed the interrelationship between the pulse chasing and time and frequency/phase synchronization and described the effects of the identified system instability factors on two kinds of MTI filter configuration, single delay-line and double delay-line, in the bistatic radar. And also, we have confirmed that the overall system improvement is restricted by a lower improvement factor among identified them, and discussed the allowable tolerance of the time and frequency/phase synchronization in the bistatic system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권2호
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• pp.723-743
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• 2016

Indoor positioning is considered an enabler for a variety of applications, the demand for an indoor positioning service has also been accelerated. That is because that people spend most of their time indoor environment. Meanwhile, the smartphone integrated powerful camera is an efficient platform for navigation and positioning. However, for high accuracy indoor positioning by using a smartphone, there are two constraints that includes: (1) limited computational and memory resources of smartphone; (2) users' moving in large buildings. To address those issues, this paper uses the TC-OFDM for calculating the coarse positioning information includes horizontal and altitude information for assisting smartphone camera-based positioning. Moreover, a unified representation model of image features under variety of scenarios whose name is FAST-SURF is established for computing the fine location. Finally, an optimization marginalized particle filter is proposed for fusing the positioning information from TC-OFDM and images. The experimental result shows that the wide location detection accuracy is 0.823 m (1σ) at horizontal and 0.5 m at vertical. Comparing to the WiFi-based and ibeacon-based positioning methods, our method is powerful while being easy to be deployed and optimized.

• International journal of advanced smart convergence
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• 제10권4호
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• pp.241-255
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• 2021

The human auricle is the first part to receive sound from the outside. In this part, the frequency range of human recognizable form is divided and organized. In this study, we propose modeling by applying a single sound source to the surface of the human auricle. This means that when the sound pressure of a low frequency (low frequency) sound enters the pinna, the impedance felt at the tip of a part of the non-linear surface of the pinna is mainly due to the tensile force at the end of the part of the non-linear surface of the pinna. By expressing the situation of moving at a very small speed, the characteristic impedance of the pinna was confirmed to be negative infinity, and it was also confirmed that the speed at the tip of a part of the non-linear surface of the pinna was 0 in the anti-resonance state. It was found that the wave propagation phenomenon that determines the characteristics of the filter is determined by how large the wavelength, kL, is compared to the length of the tip of a part of the non-straight surface of the pinna. Humans first receive sounds from outside through their ears. The auricle is non-linear and has a curved shape, and it is known that it analyzes frequencies while receiving external sounds. The human ear has an audible frequency range of 20Hz - 20,000Hz. Through the study, we applied the characteristics of the notch filter to hypothesize that the human audible frequency range is separated from the auricle, and applied filter theory to analyze it, and as a result, meaningful results were obtained. The curved part and the inner part of the auricle function as a trumpet, collecting sounds, and at the same time amplifying the weak sound of a specific band. The point was found and the shape of the envelope detected in the auricle was found. Selectivity for selecting sounds coming from the outside is the formula of the pinna that implements the function of Q. The function of distinguishing human-recognizable sound from the pinna from low to high through frequency analysis is performed in the pinna, and the 2-3kHz area, where human hearing threshold is the most sensitive, is also the acoustic impedance of the most recessed area of the pinna. It can be seen that starting from.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.35-38
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• 2003

In this paper, I propose an automatic background extraction method and continuous background updating technique. Because there is a movement of a vehicle and a change of a background is feeble, the area moving through the time axis is looked for and a background and a vehicle image is divided. A way to give dynamically the threshold which divides the image frame into a vehicle image and the background in a space is enforced. Through the repetition of the above-mentioned process, the background pictorial image is gained. Using the karlman filter technique, the update is done so that a background image can obey a climate situation and an environmental change in day and night. A background image processed algorithm is better than the existent one. Through simulation, the feasibility of the algorithm has been verified.