• Title/Summary/Keyword: Current tracking

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A Performance Analysis of AM-SCS-MMA Adaptive Equalization Algorithm based on the Minimum Disturbance Technique (Minimum Disturbance 기법을 적용한 AM-SCS-MMA 적응 등화 알고리즘의 성능 해석)

  • Lim, Seung-Gag
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.3
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    • pp.81-87
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    • 2016
  • This paper analysis the AM-SCS-MMA (Adaptive Modulus-Soft Constraint Satisfaction-MMA) based on the adaptive modulus and minimus-disturbance technique in order to improve the stability and robustness in low signal to noise power of current MMA adaptive equalization algorithm. In AM-SCS-MMA, it updates the filter coefficient applying the adaptive modulus and minimum-disturbance technique of deterministic optimization problem instead of LMS or gradient descend algorithm for obtain the minimize the cost function of adaptive equalization. It is possible to improve the equalizer filter stability, robustness to the various noise characteristic and simultaneous reducing the intersymbol interference due to the amplitude and phase distortion occurred at channel. The computer simulation were performed for confirming the improved performance of SCS-MMA. For these, the output signal constellation of equalizer, residual isi, MSE, EMSE (Excess MSE) which means the channel traking capability and SER which means the robustness were applied. As a result of computer simulation, the AM-SCS-MMA have slow convergence time and less residual quantities after steady state, more good robustness in the poor signal to noise ratio, but poor in channel tracking capabilities was confirmed than MMA.

Performance Improvement of Pedestrian Detection using a GM-PHD Filter (GM-PHD 필터를 이용한 보행자 탐지 성능 향상 방법)

  • Lee, Yeon-Jun;Seo, Seung-Woo
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.12
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    • pp.150-157
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    • 2015
  • Pedestrian detection has largely been researched as one of the important technologies for autonomous driving vehicle and preventing accidents. There are two categories for pedestrian detection, camera-based and LIDAR-based. LIDAR-based methods have the advantage of the wide angle of view and insensitivity of illuminance change while camera-based methods have not. However, there are several problems with 3D LIDAR, such as insufficient resolution to detect distant pedestrians and decrease in detection rate in a complex situation due to segmentation error and occlusion. In this paper, two methods using GM-PHD filter are proposed to improve the poor rates of pedestrian detection algorithms based on 3D LIDAR. First one improves detection performance and resolution of object by automatic accumulation of points in previous frames onto current objects. Second one additionally enhances the detection results by applying the GM-PHD filter which is modified in order to handle the poor situation to classified multi target. A quantitative evaluation with autonomously acquired road environment data shows the proposed methods highly increase the performance of existing pedestrian detection algorithms.

Recognition of Passports using Enhanced Neural Networks and Photo Authentication (개선된 신경망과 사진 인증을 이용한 여권 인식)

  • Kim Kwang-Baek;Park Hyun-Jung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.5
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    • pp.983-989
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    • 2006
  • Current emigration and immigration control inspects passports by the naked eye, registers them by manual input, and compares them with items of database. In this paper, we propose the method to recognize information codes of passports. The proposed passport recognition method extracts character-rows of information codes by applying sobel operator, horizontal smearing, and contour tracking algorithm. The extracted letter-row regions is binarized. After a CDM mask is applied to them in order to recover the individual codes, the individual codes are extracted by applying vertical smearing. The recognizing of individual codes is performed by the RBF network whose hidden layer is applied by ART 2 algorithm and whose learning between the hidden layer and the output layer is applied by a generalized delta learning method. After a photo region is extracted from the reference of the starting point of the extracted character-rows of information codes, that region is verified by the information of luminance, edge, and hue. The verified photo region is certified by the classified features by the ART 2 algorithm. The comparing experiment with real passport images confirmed the good performance of the proposed method.

A Data Model for Past and Future Location Process of Moving Objects (이동 객체의 과거 및 미래 위치 연산을 위한 데이터 모델)

  • Jang, Seung-Youn;Ahn, Yoon-Ae;Ryu, Keun-Ho
    • The KIPS Transactions:PartD
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    • v.10D no.1
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    • pp.45-56
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    • 2003
  • In the wireless environment, according to the development of technology, which is able to obtain location information of spatiotemporal moving object, the various application systems are developed such as vehicle tracking system, forest fire management system and digital battle field system. These application systems need the data model, which is able to represent and process the continuous change of moving object. However, if moving objects are expressed by a relational model, there is a problem which is not able to store all location information that changed per every time. Also, existing data models of moving object have a week point, which constrain the query time to the time that is managed in the database such as past or current and near future. Therefore, in this paper, we propose a data model, which is able to not only express the continuous movement of moving point and moving region but also process the operation at all query time by using shape-change process and location determination functions for past and future. In addition, we apply the proposed model to forest fire management system and evaluate the validity through the implementation result.

Vector Control of SPMSM Using MATLAB/SIMULINK & dSPACE 1104 System (MATLAB/SIMULINK와 dSPACE 1104 시스템을 이용한 표면 부착형 영구자석 동기전동기 벡터제어)

  • Lee, Yong-Seok;Ji, Jun-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.2
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    • pp.317-326
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    • 2008
  • This paper presents a vector control implementation for SPMSM(Surface-mounted Permanent Magnet Synchronous Motor) using dSPACE 1104 system and MATLAB/SIMULINK. SPMSM can be treated as a DC motor provided that currents of flux and torque component are controlled independently using vector control. Therefore various control algorithms for conventional DC motor control can be adopted to SPMSM. The system is designed to improve set-point tracking capability, fast response, and accuracy In This paper, d-q equivalent modeling of PMSM is derived based on vector control theory. PI controller is used for speed control and decoupling PI controller is used for current control. For the implementation of high performance vector control system, dSPACE 1104 system is used. Experiments were carried out to examine validity of the proposed vector control implementation.

RFID-based Automatic Entity Information Management System for Smart Refrigerator (스마트 냉장고를 위한 RFID 기반 물품 정보 자동 관리 시스템)

  • Lee, Ju-Dong;Kim, Hyung-Suk;Kim, Tae-Hyoun;Suh, Hyo-Joong
    • Journal of Internet Computing and Services
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    • v.9 no.1
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    • pp.43-54
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    • 2008
  • In this paper, we implement an automatic entity information management system for smart refrigerator using RFID technology in which objects containing electronic tags are automatically identified using radio wave. Unlike current "smart" refrigerators, the system presented in this paper implements smart tag information acquisition mechanism and real-time information management system to provide various information on entities in refrigerators to local and remote users. As the first step, this paper analyzes the requirements for smart refrigerator system based on the RFID and suggests design considerations. Based on the analysis, we propose and implement an efficient tag location tracking method based on antenna transfer method and an intelligent tag information management system based on embedded database and web server. We also provide a wide range of experimental results on the number of tags identified at a time and the tag recognition ratio according to the RFID antenna transfer speed and the angle between tag reader and tags.

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Application of trajectory data mining to improve the estimation accuracy of launcher trajectory by telemetry ground system (원격자료수신장비의 발사체궤적 추정정확도 향상을 위한 궤적데이터마이닝의 적용)

  • Lee, Sunghee;Kim, Doo-gyung;Kim, Keun-hyung
    • Journal of Korea Society of Industrial Information Systems
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    • v.20 no.5
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    • pp.1-11
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    • 2015
  • This paper is focused on how the trajectory of launch vehicle could be optimally estimated by the quadratic regression of trajectory data mining for the operation of telemetry ground system in NARO space center during real-time. To receive the telemetry data, the telemetry ground system has to track the space launch vehicle without tracking loss, and it is possible by the well-designed algorithm to estimate a flight position in real-time. For this reason, the quadratic regression model instead of interpolation was considered to estimate the exact position data of launch vehicle and the improvement of antenna performance. For analysis, the real trajectory data which had been logged during NARO 1st launch mission were used, the estimation result of launcher current position was analyzed by the mathematical modeling. In conclusion, the algorithm using quadratic regression based on trajectory data mining showed the better performance than previous interpolation algorithm to estimate the next flight position and the antenna driving performance.

A Study of the Next Generation Ubiquitous Flight Information System and a Design (차세대 유비쿼터스 비행정보 시스템의 연구와 설계)

  • Park, Wan-Soon;Yang, Hae-Sool
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.4
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    • pp.221-230
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    • 2008
  • We Studied current Flight Information System everyone employing, and this paper designed a next generation Ubiquitous Flight Information System. Studied a Ubiquitous Flight Information System regarding AVOD, game TV, cellular phone, cabin Internet use for a customer, and airline and control of Air Traffic Service, Air Traffic Control, in seat reservation, transportation, ticketing and luggage back-tracking and airplanes in earthly service. We Designed for a Next Generation Ubiquitous Flight Information System and for necessary for network security, system security of information security system, and derived from comparative analysis of improvement point and difference to existing Ubiquitous Flight Information System and Next Generation Ubiquitous Flight Information as was based on result of research. Present vision to aerial the result of research world of this paper related industry, and ensure safety and communication efficiency and a customer and flight satisfaction, efficiency, and will reclaim the new horizon to the Flight Information Industry.

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A Selectivity Estimation Technique for Current Query of Moving Objects (이동객체를 위한 현재 질의 선택율 추정 기법)

  • Chi, Jeong-Hee;Ryu, Keun-Ho;Jeong, Doo-Young
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.1 s.39
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    • pp.87-96
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    • 2006
  • Selectivity estimation is one of the query optimization techniques. It is difficult for the previous selectivity estimation techniques for moving objects to apply the position change of moving objects to synopsis. Therefore, they result in much error when estimating selectivity for queries, because they are based on the extended spatial synopsis which does not consider the property of the moving objects. In order to reduce the estimation error, the existing techniques should often rebuild the synopsis. Consequently problem occurs, that is, the whole database should be read frequently. In this paper, we proposed a moving object histogram method based on quad tree to develop a selectivity estimation technique for moving object queries. We then analyzed the performance of the proposed method through the implementation and evaluation of the proposed method. Our method can be used in various location management systems such as vehicle location tracking systems, location based services, telematics services, emergency rescue service, etc in which the location information of moving objects changes over time.

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A Recognition Framework for Facial Expression by Expression HMM and Posterior Probability (표정 HMM과 사후 확률을 이용한 얼굴 표정 인식 프레임워크)

  • Kim, Jin-Ok
    • Journal of KIISE:Computing Practices and Letters
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    • v.11 no.3
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    • pp.284-291
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    • 2005
  • I propose a framework for detecting, recognizing and classifying facial features based on learned expression patterns. The framework recognizes facial expressions by using PCA and expression HMM(EHMM) which is Hidden Markov Model (HMM) approach to represent the spatial information and the temporal dynamics of the time varying visual expression patterns. Because the low level spatial feature extraction is fused with the temporal analysis, a unified spatio-temporal approach of HMM to common detection, tracking and classification problems is effective. The proposed recognition framework is accomplished by applying posterior probability between current visual observations and previous visual evidences. Consequently, the framework shows accurate and robust results of recognition on as well simple expressions as basic 6 facial feature patterns. The method allows us to perform a set of important tasks such as facial-expression recognition, HCI and key-frame extraction.