• 제목/요약/키워드: least time principle

검색결과 40건 처리시간 0.026초

RLS 알고리즘을 이용한 원격 RF 센서 시스템의 시변 파라메타 추정 (Time-Varying Parameter Estimation of Passive Telemetry RF Sensor System Using RLS Algorithm)

  • 김경엽;유동국;이준탁
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
    • /
    • pp.29-33
    • /
    • 2007
  • 본 연구에서는 RLS(Rescursive Least Square) 알고리즘을 이용하여 정전용량형 습도센서를 사용한 원격 RF 센서 시스템의 시변 파라메타를 추정하고자 한다. IC 칩 형태의 원격 RF 센서 시스템이 가지는 구성의 복잡성 그리고 전력소모 문제를 해결하기 위해 보다 간단한 유도결합모델이 제안된다. 모델기반의 RLS 알고리즘을 수학적인 모델로 유도된 시스템에 적용시키기 위해 페이저법을 이용하여 모델의 파라메타를 재배열한다. 오차 제곱합의 수렴특성을 가진 RLS 알고리즘을 이용하여 시변 파라메타를 추정하며, 잡음을 내포한 측정 데이터에 대한 추정 성능을 확인함으로써 그 유효성을 검증하고자 한다.

  • PDF

Multi-Prame MQD-PIV

  • Suh, Yong-Kweon
    • Journal of Mechanical Science and Technology
    • /
    • 제17권10호
    • /
    • pp.1552-1562
    • /
    • 2003
  • In this paper, we propose a new PIV methodology for obtaining a velocity field from a sequence of multiple image data based on a least-square principle (also known as MQD; minimum quadratic difference) for the grey level difference between two neighboring frames of image data. We investigated both the accuracy of the result and the time consumption in the computation. It turns out that the proposed method is not only accurate but fast compared with the conventional correlation PIV techniques. Our method is applied to the spin-up flows and the results show that the method can be a good substitution for the conventional algorithms employed in the existing commercial codes.

평면 비행중인 항공기의 쌍곡선 위치 추정 연구 (Hyperbolic Location Estimation of Aircraft with Motion in a Plane)

  • 조상훈;강자영
    • 한국항공운항학회지
    • /
    • 제21권2호
    • /
    • pp.33-39
    • /
    • 2013
  • Multilateration(MLAT) may complement secondary surveillance radar and also act as a real-time backup for the ADS-B system. This System is using time difference of arrival (TDOA) and based on triangulation principle. Each TDOA measurement defines a hyperbola describing possible aircraft locations. The accuracy in MLAT system depends on the positional relationship of the receiver and aircraft. There are various algorithms to localize aircraft based on TOA estimation. In this paper, we use least square method and extended Kalman filter and compare their results. Study results show that the extend Kalman filter provides a better performance than the least square method.

RLSE알고리즘을 이용한 원격 정전용량형 습도 센서 시스템 (Passive Telemetry Capacitive Humidity Sensor System using RLSE Algorithm)

  • Kyung-Yup Kim;Joon-Tark Lee
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제28권4호
    • /
    • pp.569-576
    • /
    • 2004
  • In this paper, passive telemetry capacitive humidity sensor system using a RLSE(Recursive Least Square Estimation) technique is proposed. To overcome the problem like power limits and complications that general passive telemetry sensor system including IC chip has, the principle of inductive coupling is applied to model the sensor system. Specially. by applying the forgetting factor we show that the accuracy of its estimation can be improved even in the case of time varying parameter and also the convergence time can be reduced.

1-Point Ransac Based Robust Visual Odometry

  • Nguyen, Van Cuong;Heo, Moon Beom;Jee, Gyu-In
    • Journal of Positioning, Navigation, and Timing
    • /
    • 제2권1호
    • /
    • pp.81-89
    • /
    • 2013
  • Many of the current visual odometry algorithms suffer from some extreme limitations such as requiring a high amount of computation time, complex algorithms, and not working in urban environments. In this paper, we present an approach that can solve all the above problems using a single camera. Using a planar motion assumption and Ackermann's principle of motion, we construct the vehicle's motion model as a circular planar motion (2DOF). Then, we adopt a 1-point method to improve the Ransac algorithm and the relative motion estimation. In the Ransac algorithm, we use a 1-point method to generate the hypothesis and then adopt the Levenberg-Marquardt method to minimize the geometric error function and verify inliers. In motion estimation, we combine the 1-point method with a simple least-square minimization solution to handle cases in which only a few feature points are present. The 1-point method is the key to speed up our visual odometry application to real-time systems. Finally, a Bundle Adjustment algorithm is adopted to refine the pose estimation. The results on real datasets in urban dynamic environments demonstrate the effectiveness of our proposed algorithm.

Newton-Raphson법 기반의 적응 망각율을 갖는 RLS 알고리즘에 의한 원격센서시스템의 시변파라메타 추정 (Time Variant Parameter Estimation using RLS Algorithm with Adaptive Forgetting Factor Based on Newton-Raphson Method)

  • 김경엽;이준탁
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2007년도 춘계학술대회 학술발표 논문집 제17권 제1호
    • /
    • pp.435-439
    • /
    • 2007
  • This paper deals with RLS algorithm using Newton-Raphson method based adaptive forgetting factor for a passive telemetry RF sensor system in order to estimate the time variant parameter to be included in RF sensor model. For this estimation with RLS algorithm, phasor typed RF sensor system modelled with inductive coupling principle is used. Instead of applying constant forgetting factor to estimate time variant parameter, the adaptive forgetting factor based on Newton-Raphson method is applied to RLS algorithm without constant forgetting factor to be determined intuitively. Finally, we provide numerical examples to evaluate the feasibility and generality of the proposed method in this paper.

  • PDF

Passive Telemetry Sensor System using RLSE Based Real Time Estimation Technique with Optimal Forgetting Factor

  • Lee, Joon-Tark;Kim, Kyung-Yup
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2004년도 추계학술대회 학술발표 논문집 제14권 제2호
    • /
    • pp.515-520
    • /
    • 2004
  • In this paper, a passive telemetry RF capacitive humidity sensor system using a RLSE(Recursive Least Square Estimation) technique is proposed. To overcome these trouble problems such as a power limitation and a estimation complexity that the general passive telemetry sensor system including It chip has, the principle of inductive coupling was applied to the modeling of a passive telemetry RF capacitive humidity sensor system and its capacitance was estimatedd by the RLSE algorithm. Specially, by introducing the optimal forgetting factor, we showed that the accuracy of its estimation was improved even in the time varying system and also the convergence time was reduced.

  • PDF

Passive Telemetry Capacitive Humidity Sensor System using RLSE Algorithm

  • Lee, Joon-Tark;Park, Young-sik;Kim, Kyung-Yup
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
    • /
    • pp.495-498
    • /
    • 2004
  • In this paper, passive telemetry capacitive humidity sensor system using a RLSE(Recursive Least Square Estimation) technique Is proposed. To overcome the problem like power limits and complications that general passive telemetry sensor system including IC chip has, the principle of inductive coupling is applied to model the sensor system. Specially, by applying the forgetting factor, we show that the accuracy of its estimation can be improved even in the case of time varying parameter and also the convergence time can be reduced.

  • PDF

남성 난임에 대한 한의학적 연구 - 원인, 생식 건강 증진법, 임신 성공률 제고를 위한 성생활법 및 대표처방을 중심으로 - (Korean Medical Study on Male Infertility - Focusing on Cause, Reproductive Health Improvement, Sexual Tips to Improve Pregnancy Success Rate and Major Formulas -)

  • 김연태
    • 대한한의학원전학회지
    • /
    • 제36권4호
    • /
    • pp.55-67
    • /
    • 2023
  • Objectives : Contents on causes of male infertility, reproductive health improvement, sexual tips were studied in classical texts of Korean Medicine, followed by representative formulas for male infertility treatment. Methods : Related texts from the Qiusimen chapters of the Yixuerumen, Yixuexinwu, Donguibogam, Nukejinglun, Jiaozhufurenliangfang, Jiyingandmu were collected, and their medical meaning discussed. Results : As immoderate libido and excessive mental consumption leads to sexual dysfunction causing male infertility, 'moderating sexual desire and accumulating Jing' should be the principle for improving reproductive health. Also, sufficient foreplay is recommended. In terms of formula, the Wuziyanzongwan with sufficient therapeutic evidence in both classical texts and contemporary Korean Medicine can be applied in cases of male infertility. Conclusions : Excessive sensual stimulation and immoderate sexual desire consumes the mind and results in decline in male reproductive health. While moderating sexual desire and accumulating Jing through controlling desire, not overworking, moderating anger, drinking in moderation, balanced eating should be the principle for improving reproductive health, having sexual intercourse 2~3 times per week rather than long-term abstinence is recommended. To improve the success rate in pregnancy, sufficient foreplay and time should be done and taken for intercourse. Wuziyanzongwan should be taken for at least three months or longer.

유동성 재료의 동적 거동 해석을 위한 입자확대법 기반 DEM의 적용 (Application of DEM with Coarse Graining Method to Fluidal Material Behavior Analysis)

  • 윤태영
    • 한국도로학회논문집
    • /
    • 제19권6호
    • /
    • pp.23-30
    • /
    • 2017
  • PURPOSES : In this paper, the applicability of DEM to a coarse graining method was evaluated by simulating a series of minicone tests for cement paste. METHODS : First, the fundamental physical quantities that are used in a static liquid bridge model were presented with three basic quantities based on the similarity principle and coarse graining method. Then, the scale factors and surface tensions for six different sizes of particles were determined using the relationship between the physical quantities and the basic quantities. Finally, the determined surface tensions and radii were utilized to simulate the fluidal behavior of cement paste under a minicone test condition, and the final shape of the cement paste with reference DEM particle radii was compared with the final shape of the others. RESULTS : The simulations with adjusted surface tensions for five different radii of particles and surface tension showed acceptable agreement with the simulation with regard to the reference size of the particle, although disagreement increases as the sizes of the particle radii increase. It seems reasonable to increase the particle radii by at least 0.196 cm considering the computational time reduction of 162 min. CONCLUSIONS : The coarse graining method based on the similarity principle is applicable for simulating the behavior of fluidal materials when the behavior of the materials can be described by a static liquid bridge model. However, the maximum particle radius should be suggested by considering not only the scale factor but also the relationship of the particle size and number with the radius of the curve of the boundary geometry.