• 한국정밀공학회지
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• 제25권10호
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• pp.122-129
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• 2008

This paper deals with precise positioning of a high-speed positioning stage without inducing residual vibration by using an input shaping technique. Input shaping is well known to be a very effective tool for suppressing the residual vibration of flexible structures. However, the ordinary input shaping for positioning stages is designated mostly for velocity regulation, not for the residual vibration at the target position. The main difficulties in implementing input shaping along with precise positioning are the time delay caused by the servo system characteristics and the s-curve feature often employed in some motor controllers. This paper analyzes the dynamic responses of a single-mode-dominate stage system subjected to input shaping. A theoretical model is developed io investigate the nature of system. In order to overcome the difficulty, this paper proposes an improved input shaper based on modified command profile generation. The proposed method is proved effective through experiments and simulations.

• 산업공학
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• 제23권3호
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• pp.239-245
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• 2010

This paper considers a localization problem of a moving tag on RFID(Radio Frequency Identification) systems, where a positioning engine collects TDOA(Time-difference of Arrival) signal from a target tag to estimate the position of the tag. To localize the tag in the RFID system, we develop two heuristic algorithms and evaluate their performance in the estimation error and computational time by using randomly generated numerical examples. Based upon the performance evaluation, we can conclude our algorithms are valuable for localization the moving target.

• 한국컴퓨터정보학회논문지
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• 제20권3호
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• pp.57-67
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• 2015

본 논문에서는 적외선 영상에서 탐지된 표적의 픽셀정보를 이용하여 실제 환경에서의 표적의 위치를 추정하는 geolocation 기법에 대하여 제안한다. 제안하는 기법은 지대지 전장 환경에서 공중 정찰을 통한 적대 표적의 위치를 파악하는 시스템에 적용이 가능하다. 적대 표적의 geolocation에 영향을 주는 요소는, 시스템의 광학적 왜곡, 지형적 왜곡, 정찰 모듈의 GPS(Global Positioning System) 및 IMU(Inertial Measurement Unit) 왜곡을 들 수 있다. 본 논문에서는 광학적 왜곡과 지형적 왜곡에 적응적인 geolocation 을 위하여 광학 정보의 다항식 최적화와 지구 곡률을 고려한 시선거리 계산 기법을 적용하였으며, 3차원 모의 환경에서 실험한 결과 시스템 요구사항 내에서 geolocation의 정확도를 만족함을 확인하였다.

• 전자공학회논문지
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• 제52권3호
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• pp.13-18
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• 2015

본 논문은 GNSS의 문제점인 위치오차와 실외음영지역을 해소하기 위하여 GNSS와 vision system을 융합한 신뢰성있는 고정밀 측위와 최적의 vision system을 분석하였다. 위치결정을 위해서는 최소 4개 이상의 GNSS로부터 신호를 수신 받아야 한다. 그러나 도심지역에서는 고층건물이나 장애물 또는 반사파에 의해 정확한 위치가 어렵다. 이러한 문제점을 해결하기 위하여 vision system을 이용한다. GNSS를 사용하기 열악한 도심지역의 target object에 정확한 위치 값을 결정해 놓는다. 그리고 vision system을 이용해 target object를 인식하고, 인식된 target object를 이용하여 위치오차를 보정해 준다. 이동체는 이동 중 vision system을 이용하여 target object를 인식하여 위치 데이터 값을 만들어내고, 위치 계산을 수정하여 안정되고 신뢰성 있는 고정밀 측위를 할 수 있다.

• 반도체디스플레이기술학회지
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• 제12권1호
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• pp.53-59
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• 2013

Chip mounter which is used to pick chips from the pre-specified position and place them on the target location of PCB is an essential device in semiconductor and LCD industries. Quick and high precision positioning is the key technology needed to increase productivity of chip mounters. As increasing acceleration and deceleration of placing motion, structural vibration induced from inertial reactive force and flexibility of mounter structure becomes a serious problem degrading positioning accuracy. Motivated from these, this paper proposed a new control design algorithm which combines a mounter structure acceleration feedforward compensation and an extended sliding mode control for fine positioning and suppression of structural vibration, simultaneously. The feasibility of the proposed control design was verified along with some simulation results.

• Journal of information and communication convergence engineering
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• 제8권3호
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• pp.339-342
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• 2010

An iris image pattern positioning with preserved edge detector, ring zone and clock zone, frequency distribution and overlay matching is presented in this paper. Edge detector is required to be powerful and detail. That is proposed by overlaying Canny with LOG (CLOG). The two reference patterns are made from allocating each gray level on the clock zone and ring zone respectively. The normalized target image is overlaid with the clock zone reference pattern and the ring zone pattern to extract overlapped number, and make a matched frequency distribution to look through a symptom and position of human organ and tissue. The iterating experiments result in the ring and clock zone positioning evaluation.

• 제어로봇시스템학회논문지
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• 제10권4호
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• pp.317-324
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• 2004

The ink jet printer media advance system is required to be exactly driven to the target position via tracking the reference velocity profile to obtain the high quality print image. A single gain PID controller is not sufficient to fulfill the control objectives, the exact velocity tracking and the accurate positioning, at the same time. A dual PID controller and its switching strategy are presented in this paper to achieve the control objectives. The media advance system is controlled by two separate PID controllers, one of which is for velocity control, and the other is for position control. A PID controller controls the velocity of the media advance system until it reaches the predetermined switching position. When the media advance system passes the predetermined position, the controller is switched to the other PID controller which is more profitable for exact positioning. The switching position is determined by the estimated stop distance. The simulation and experimental results are presented to show the validity and effectiveness of the proposed controller.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.129-132
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• 1996

There is a tendency nowadays to produce increasingly miniaturized electronic equipment which incorporate parts that have to be precisely positioned, like lenses, heads and CCD's in scanners, printers, copiers, VCR's, optical fiber modules, etc. In contrast to the production process of precision parts, which is currently being carried out automatically, the assemblage process is still being performed by specially skilled technicians. The assemblage process comprises normally the following steps: firstly, the parts are roughly positioned and partially fixed, secondly, the parts are manually nudged towards the target position and finally glued, screwed or welded. This paper presents a system that uses six piezo Impact Drive Mechanisms for accurate micro positioning within three degrees of freedom (lateral and longitudinal translation and rotation). The system is designed to positioning a printed circuit board with an accuracy better than 3 .mu.m (for translations), 5 mrad (for rotation).

• Journal of Positioning, Navigation, and Timing
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• 제13권2호
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• pp.137-147
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• 2024

This paper presents a novel Long Short-Term Memory (LSTM) network architecture for the integration of an Inertial Measurement Unit (IMU) and Global Navigation Satellite Systems (GNSS). The proposed algorithm consists of two independent LSTM networks and the LSTM networks are trained to predict attitudes and velocities from the sequence of IMU measurements and mechanization solutions. In this paper, three GNSS receivers are used to provide Real Time Kinematic (RTK) GNSS attitude and position information of a vehicle, and the information is used as a target output while training the network. The performance of the proposed method was evaluated with both experimental and simulation data using a lowcost IMU and three RTK-GNSS receivers. The test results showed that the proposed LSTM network could improve positioning accuracy by more than 90% compared to the position solutions obtained using a conventional Kalman filter based IMU/GNSS integration for more than 30 seconds of GNSS outages.

• 패션비즈니스
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• 제9권3호
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• pp.8-21
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• 2005

The purpose at this study was to analyze and to position the clothing images at women's formal wear brands carried by at least two department stores in Daejon, for providing data for a basic marketing strategy for fashion manufacturers and distributors. The results tram the study were as tallows; The brand that showed the highest classic image was 'BCBG'(83.6%), the brand that showed the highest feminine image was 'Obzee' (80.2%), the brand that showed the highest character image was 'Doho' (84.1%), and the brand that showed the highest mannish image was 'F.Station' (64.1%). On the brands image positioning map, brands, such as 'Deco', 'Mine', 'Time', and 'Anne Klein', lying on or near the point of intersection (where the vertical and horizontal axes meet) showed 4 types. They were 'smart & chic cluster', 'charming & luxury cluster', 'character elegance cluster', and 'sportive elegance cluster' that showed compound images. These clusters would be differentiated tram young casual lines by emphasizing the brands' shape and cut, higher quality fabrics and materials, and elegant and graceful colors. Analysis of target ages and tweed jacket prices for brands carried by at least two department stores showed that the target was between 23 and 50, and that the prices range from 198,000 won to 460,000 won.