• 제목/요약/키워드: initialization method

검색결과 187건 처리시간 0.025초

레이저스케너 센서기반의 칼만필터 관측을 이용한 사람이동예측 (Estimation of People Tracking by Kalman Filter based Observations from Laser Range Sensor)

  • 진태석
    • 한국산업융합학회 논문집
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    • 제22권3호
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    • pp.265-272
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    • 2019
  • For tracking a varying number of people using laser range finder, it is important to deal with appearance/disappearance of people due to various causes including occlusions. We propose a method for tracking people with automatic initialization by integrating observations from laser range finder. In our method, the problem of estimating 2D positions and orientations of multiple people's walking direction is formulated based on a mixture kalman filter. Proposal distributions of a kalman filter are constructed by using a mixture model that incorporates information from a laser range scanner. Our experimental results demonstrate the effectiveness and robustness of our method.

인천지역 통합기준점에서 Network-RTK 측량기법의 비교 (Comparison of Network-RTK Surveying Methods at Unified Control Stations in Incheon Area)

  • 이용창
    • 한국측량학회지
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    • 제32권5호
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    • pp.469-479
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    • 2014
  • 네트워크 RTK 기술은 전리층 및 대류층 지연, 위성 궤도력 오차 등과 같은 거리에 종속된 오차의 보정모델링을 통해 GNSS 측위 정확도를 향상할 수 있는 기법이다. 본 연구에서는 전리층 교란의 극대화 시기인 Cycle24 기간 중, 인천지역 내 20점의 통합기준점을 대상으로 N-RTK (VRS 및 FKP) 측량을 실시하고 초기화시간, 성분별 측위정확도 및 좌표 교차를 비교 분석하였다. 연구결과, 측위정확도는 VRS가 FKP에 비해 우수하였고 두 기법 모두, 고도성분은 수평성분에 비해 2배 이상의 표준편차를 보였는데 이는 전자밀도 변동에 따른 전리층교란과 굴절지수의 변동으로 발생되는 대류층의 요동에 따른 것으로 보인다. 각 통합기준점에서 기법별 초기화는 VRS가 FKP에 비해 빠르게 수렴되었다. 이는 N-RTK를 위한 표준화된 고압축 전송형식의 활용과 국내 이동 통신 인프라에 의한 기준국 보정신호의 신호지연이 최소라는 고려 하에서 두 기법간의 기본원리의 차이, 서로 다른 보정 기준망에 따른 상이한 오차특성 및 FKP 보정값의 비선형 특성에 기인된 것으로 분석된다. 특히, 태양흑점폭발과 플레어로 인하여 우주전파환경의 변화가 발생되는 동안에 정확도의 저하, 초기화시간의 연장, 관측도중 재초기화, 심한 경우 초기화 실패 등의 현상이 발생됨을 확인할 수 있었다.

유전알고리즘을 이용한 비선형시스템의 연속시간 퍼지모델링 (Continuous-time fuzzy modelling of nonlinear systems using genetic algorithms)

  • 이현식;진강규
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.1473-1476
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    • 1997
  • This paper presents a scheme for continuous-time fuzzy modelling of nonlinear systems, based on the adjustment technique and the genetic algorithm technque. The fuzzy model is characterized by fuzzy "If-then" rules whcih represent locally linear input-output relations whose consequence part is defined as subsystem of a nonlinear system. To compute the final output and deal with the initialization and unmeasurable signal problems in on-line estimatio of the fuzzy model, a discrete-time model is obtaned. Then the parameters of both the premis and consequence of the fuzzy model are adjusted on-line by a genetic algorithm. A simulation work is carried out to demonstrate the effectiveness of the proposed method.ed method.

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Time-stews를 고려한 CMOS회로의 테스트 생성 알고리즘 (Test Generation Algorithm for CMOS Circuits considering Time - skews)

  • 이철원;한석붕;김윤홍;정준모;선선구;임인칠
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.1551-1555
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    • 1987
  • This paper proposes a new test generation algorithm to detect stuck-open faults regardless of tine-skews in CMOS circuits. For testing for stuck-open faults regardless of time-skews, in this method, Hamming distance between the initialization pattern and the test pattern is made 1 by considering the responses of the internal gates. Therefore, procedure of the algorithm is simpler than that of the conventional methods because the line justification is unnecessary. Also, this method needs no extra hardware for testability and can be applied to random CMOS circuits in addition to two-level NAND - NAND CMOS circuits.

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다층 손실 유전체를 이용한 광대역 전파 흡수체 설계 (Design of broad-band radar absorbing materials using multi-layered lossy dielectrics)

  • 이동근;남기진;이상설
    • 전자공학회논문지D
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    • 제34D권3호
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    • pp.17-24
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    • 1997
  • Broad-band RAM's (Radar absorbing materials) are designed by multi-layered lossy dielectrics. The depth, the relative permittivity and the loss tangent of each layer are optimized in order to meet the required reflective power over the specified frequency range using a genetic algorithm. The reflection coefficients are calculated by the continued fraction method. A new population model of the partial initialization method during iterations is applied for the multi-modal functions to enhance the performance of the genetic algorithm. The optimal RAN's are designed by setting the relative permittivity and the loss tangent of the dielectrics as a funtion of the frequency over 5~20GHz.

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다중경로 페이딩 채널에서 W-CDMA 시스템을 위한 등화 알고리즘의 성능분석 (A Performance Analysis of Equalization Algorithm for W-CDMA Systems in Multipath Fading Channels)

  • 신명식;양해술
    • 정보통신설비학회논문지
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    • 제8권4호
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    • pp.201-206
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    • 2009
  • The third generation mobile communications system requiring the reliable multimedia data transmission has provided with the reliable voice, data and video services over the variable propagation environment. However the broadband wireless multiple access technologies cause Inter Symbol Interference (ISI) or Multiple Access Interference (MAI) to degrade the performance of W-CDMA (Code Division Multiple Access) system. Constant Modulus Algorithm (CMA) which is frequently used as the adaptive blind equalizers to remove the interfering signal has ill-convergence phenomenon without proper initialization. In this paper, new blind equalization method based on conventional CMA is proposed to improve the channel efficiency, and through computer simulation this is tested over the time varying fading environment of mobile communication system. Consequently, new blind equalization method into concatenated Kalman filter with CMA is verified better than conventional CMA through adopting minimum mean square errors and eye-pattern obtained from algorithm are compared.

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PICNET-NP 통신망의 신뢰성 검증을 위한 시뮬레이션 구현 (A realization of simulator for reliability verification of the communication network PICNET-NP)

  • 이성우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 D
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    • pp.2212-2215
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    • 2002
  • This dissertation suggests and implements a middle level network which is called PICNET-NP (Plant Implementation and Control Network for Nuclear Power Plant). PICNET-NP is based partly on IEEE 802.4 token-passing bus access method and partly on IEEE 802.3 physical layer. For this purpose a new interface a physical layer service translator, is introduced. A control network using this method is implemented and applied to a distributed real-time system. To verify the performance of proposed protocol experimental were carried out, and the following results are obtained. 1) proper initialization of the protocol. 2) normal receiving and transmission of data. 3) proper switching of transmission media in case of a fault condition on the one of transmission media. The proposed protocol exhibits the excellent performance in the experimental system. From the test results in the experimental system, the proposed protocol, PICNET-NP, can be used for the upgrading of a nuclear power plant and the distributed control system in the next generation of nuclear power plant.

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진화 프로그램을 이용한 퍼지 클러스터링 (Fuzzy Clustering using Evolution Program)

  • 정창호;임영희;박주영;박대희
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제26권1호
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    • pp.130-130
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    • 1999
  • In this paper, we propose a novel design method for improving performance of existing FCM-type clustering algorithms. First, we define the performance measure which focuses on bothcompactness and separation of clusters. Next, we optimize this measure using evolution program.Especially the proposed method has following merits: ① using evolution program, it solves suchproblems as initialization, number of clusters, and convergence to local optimum ② it reduces searchspace and improves convergence speed of algorithm since it represents chromosome with possiblepotential centers which are selected possible candidates of centers by density measure ③ it improvesperformance of clustering algorithm with the performance index which embedded both compactnessand separation Properties ④ it is robust to noise data since it minimizes its effect on center search.

새로운 신호시스템 도입에 따른 열차운행 보증기술에 관한 고찰 (A study on the train operation assurance method for installing new signalling system)

  • 조봉관;류상환;김종기
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2002년도 추계학술대회 논문집(I)
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    • pp.453-458
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    • 2002
  • East Japan Railway Company developed an digital ATC signalling system instead of conventional ATC system and now is making progress the construction tokyo area Keihin-Tohoku Line between Minamiurawa and Tsurumi. But replacing into new system with existing ATC system in operation should be performed without affecting current running system and the technology that makes it possible for current system and new system to coexist, initialization of system, preparation for an emergency should be organized not to affect overall system. Controlling method of digital ATC signalling system and "assurance technique" for solving the problems when replacing will be mentioned in this paper.

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유클리드 카메라 보정을 하지 않는 비디오 기반 증강현실 (Video-Based Augmented Reality without Euclidean Camera Calibration)

  • 서용덕
    • 한국컴퓨터그래픽스학회논문지
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    • 제9권3호
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    • pp.15-21
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    • 2003
  • An algorithm is developed for augmenting a real video with virtual graphics objects without computing Euclidean information. Real motion of the camera is obtained in affine space by a direct linear method using image matches. Then, virtual camera is provided by determining the locations of four basis points in two input images as initialization process. The four pairs of 2D location and its 3D affine coordinates provide Euclidean orthographic projection camera through the whole video sequence. Our method has the capability of generating views of objects shaded by virtual light sources, because we can make use of all the functions of the graphics library written on the basis of Euclidean geometry. Our novel formulation and experimental results with real video sequences are presented.

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