• 항공우주산업기술동향
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• 제7권1호
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• pp.113-118
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• 2009

추적레이다는 안테나로부터 폭이 매우 좁은 펄스를 표적에 위치시켜 표적에서 돌아오는 신호를 수신하여 표적의 위치 (거리, 각도, 속도 등)를 추적하는 장비이다. 추적레이다가 특정한 표적을 탐지하고 추적하기에 앞서 표적과 주변 환경의 특성을 예측하기 위해 잡음 신호와 표적 신호의 수학적 모델이 필요하다. 본 논문에서는 일반적으로 적용되는 잡음 신호와 표적 신호의 모델에 대한 이론적인 내용을 소개하였고, 이와 더불어 표적의 탐지와 추적을 위한 거리 추적, 각도 추적 및 도플러 주파수 추적에 대한 일반적인 기법들을 기술하였다.

• 제어로봇시스템학회논문지
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• 제17권4호
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• pp.388-396
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• 2011

Sun tracking system is the most important subsystem in parabolic dish type solar thermal power plant, since it determines the amount of thermal energy to be collected, thus affects the efficiency of solar thermal power plant most significantly. Various types of sun tracking systems are currently used. Among them, use of photo sensors to located the sun(which is called sensor type) and use of astronomical algorithm to compute the sun position(which is called program type) are two of the mostly used methods. Recently some uses CCD sensor, like CCD camera, which is called image processing type sun tracking system. This work is concerned with the analysis of sun tracking performance of various types of sun tracking systems currently used in the parabolic dish type solar thermal power plant. We first developed a sun tracking error measurement system. Then, we evaluate the performance of five different types of sun tracking systems, sensor type, program type, hybrid type(use of sensor and computed sun position simultaneously), tracking error compensated program type and image processing type. Experimentally obtained data shows that the tracking error compensated program type sun tracking system is very effective and could provide a good sun tracking performance. Also the data obtained shows that the performance of sensor type sun tracking system is being affected by the cloud significantly, while the performance of a program type sun tracking system is being affected by the sun tracking system's mechanical and installation errors very much. Finally image processing type sun tracking system can provide accurate sun tracking performance, but costs more and requires more computational time.

• 한국수자원학회논문집
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• 제47권4호
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• pp.357-370
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• 2014

본 연구에서는 격자기반의 공간분포 강우장에서 호우지속기간동안 지속시간별 면적최대강우량을 산정할 수 있는 탐색기법을 개발하여 DAD 분석을 실시하고 그 적용성을 평가하고자 한다. 우선, 세 가지 탐색기법(Box-tracking, Point-tracking, Advanced point-tracking)의 알고리즘을 구성하고, 가상의 강우장(1 hr 지속시간)을 대상으로 각 탐색기법의 성능을 검증하였다. 다음으로 용담댐 유역의 실제 강우사상을 선택하여 개발된 탐색기법과 GIS를 이용한 고전적인 방법을 사용하여 DAD 분석을 실시하고 그 결과를 비교 분석하였다. Box-tracking의 경우, Point-tracking과 Advanced point-tracking에 비하여 상대적으로 빠른 검색이 가능하지만, 강우장의 공간분포 형태를 고려하지 못하여 타 탐색기법에 비해 유역크기별 면적최대강우량이 과대 산정되었다. 반면, Point-tracking과 Advanced point-tracking은 강우장의 공간분포 형태를 적절하게 반영하여 면적최대강우량 산정이 가능하였으며, 특히 두개 이상의 호우중심이 존재할 경우 Advanced point-tracking은 Point-tracking보다 우수한 탐색성능을 보여주었다. 따라서 본 연구에서 제안하는 탐색기법은 DAD 분석 및 면적감소계수 계산을 위한 유용한 도구로 활용이 가능할 것으로 판단된다.

• 한국소음진동공학회논문집
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• 제15권5호
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• pp.578-585
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• 2005

In this paper, we present a schematic method estimating the tracking vibration quantity occurring in the track-following system of an optical recording device. A tracking loop gain adjustment algorithm is introduced to estimate accurately the tracking vibration quantity in spite of the uncertainties of the tracking actuator, Accordingly, the tracking vibration quantity can be estimated from the tracking error, the controller output, the nominal actuator model, and a compensated gain. An optimal tracking controller can be designed from a minimum tracking open-loop gain calculated by the estimated tracking vibration quantity The proposed vibration quantity estimation and controller design method are applied to the track-following system of an optical recording device and are evaluated through the experimental result.

• 제어로봇시스템학회논문지
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• 제13권9호
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• pp.856-860
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• 2007

This paper presents a robust tracking controller design method for the track-following system of an optical recording device. A tracking loop gain adjustment algorithm is introduced to accurately estimate the tracking vibration quantity in spite of the uncertainties of the tracking actuator. A minimum tracking open-loop gain is calculated by the estimated tracking vibration quantity and a tolerable limit of tracking error. A robust tracking controller is designed by considering a robust $H_\infty$ control problem with the weighting function of a slightly larger gain than the minimum tracking open-loop gain. The proposed controller design method is applied to the track-following system of an optical recording device and is evaluated through the experimental result.

• 기술사
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• 제42권6호
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• pp.53-57
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• 2009

Antenna Tracking System has been required core technology with special tracking algorithm, and it can be achieved by program tracking, step tracking, optracking, and monopulse tracking as well. Depend on tracking requirement we might be able to apply eligible tracking method in accordance with Geostationary and Inclined Orbit Satellite. Further, we should deeply consider two important factors in order to act up to customer expectation in quality and system performance including competitive price therefore we need maximized endeavor to upgrade not only tracking system performance, but reduction of product through engineering skill and R&D investment.

• 한국군사과학기술학회지
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• 제11권1호
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• pp.85-92
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• 2008

An architecture for multiple radar tracking systems can be broadly categorized according to the methods in which the tracking functions are performed : central-level tracking and distributed tracking. In the central-level tracking, target tracking is performed using observations from all radar systems. This architecture provides optimal solution to target tracking. In distributed tracking, tracking is performed at each radar system and the composite track information is formed through track fusion integrating multiple radar-level tracks. Track-to-track fusion and track-to-track association are required to perform in this architecture. In this paper, issues and recent research on the two tracking architectures are surveyed.

• 제어로봇시스템학회논문지
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• 제16권8호
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• pp.766-770
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• 2010

In this paper, we present an effective covariance tracking algorithm based on adaptive size changing of tracking window. Recent researches have advocated the use of a covariance matrix of object image features for tracking objects instead of the conventional histogram object models used in popular algorithms. But, according to the general covariance tracking algorithm, it can not deal with the scale changes of the moving objects. The scale of the moving object often changes in various tracking environment and the tracking window(or object kernel) has to be adapted accordingly. In addition, the covariance matrix of moving objects should be adaptively updated considering of the tracking window size. We provide a solution to this problem by segmenting the moving object from the background pixels of the tracking window. Therefore, we can improve the tracking performance of the covariance tracking method. Our several simulations prove the effectiveness of the proposed method.

• 한국멀티미디어학회논문지
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• 제23권10호
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• pp.1236-1249
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• 2020

In a most recent object tracking research work, applying Convolutional Neural Network and Recurrent Neural Network-based strategies become relevant for resolving the noticeable challenges in it, like, occlusion, motion, object, and camera viewpoint variations, changing several targets, lighting variations. In this paper, the LSTM Network-based Tracking association method has proposed where the technique capable of real-time multi-object tracking by creating one of the useful LSTM networks that associated with tracking, which supports the long term tracking along with solving challenges. The LSTM network is a different neural network defined in Keras as a sequence of layers, where the Sequential classes would be a container for these layers. This purposing network structure builds with the integration of tracking association on Keras neural-network library. The tracking process has been associated with the LSTM Network feature learning output and obtained outstanding real-time detection and tracking performance. In this work, the main focus was learning trackable objects locations, appearance, and motion details, then predicting the feature location of objects on boxes according to their initial position. The performance of the joint object tracking system has shown that the LSTM network is more powerful and capable of working on a real-time multi-object tracking process.

• 한국군사과학기술학회지
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• 제11권3호
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• pp.67-75
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• 2008

In this paper, we analyze the performance of Follower Noise Jamming(FNJ) considering three practical tracking parameters such as tracking bandwidth, tracking time and tracking success probability. The performance of FNJ is compared with that of Partial-Band Noise Jamming(PBNJ) in terms of Symbol Error Rate(SER) at the communication receiver under the assumed typical operation model. It is observed that the performance of FNJ is non-linearly dependent on the tracking bandwidth, the tracking time and the tracking success probability. As we can easily expect, it is also observed that the performance of FNJ is better than that of the PBNJ. Finally, it is shown that, for a fixed tracking bandwidth, the combinations of the required tracking time and the tracking success probability which satisfy a certain required SER.