• Title/Summary/Keyword: target error

Search Result 1,292, Processing Time 0.13 seconds

Determination of Target Value under Automatic Vision Inspection Systems (자동시각검사환경하에서 공정 목표치의 설정)

  • 서순근;이성재
    • Journal of Korean Society for Quality Management
    • /
    • v.29 no.3
    • /
    • pp.66-78
    • /
    • 2001
  • This paper deals with problem of determining process target value under automated visual inspection(AVI) system. Three independent error sources - digitizing error, illumination error, and positional error - which have a close relationship with the performance of the AVI system, are considered. Assuming that digitizing error is uniformly or normally distributed and illumination and positional errors are normally distributed, respectively, the distribution function for the error of measured lengths is derived when the length of a product is measured by the AVI system. Then, Optimal target values under two error models of AVI system are obtained by minimizing the total expected cost function which consists of give away, rework and penalty cost. To validate two process setting models, AVI system for drinks filling process is made up and test results are discussed.

  • PDF

Target Positioning Error Analysis of Automatic Survey System (자동측지장비를 이용한 표적 측지 오차해석)

  • Jang, Sukwon;Lee, Taegyoo;Lee, Jinseung
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.18 no.1
    • /
    • pp.1-7
    • /
    • 2015
  • In this paper, we have described target positioning of automatic survey system. Target positioning error analysis shows target positioning errors are mainly dependent on the vertical angle of the triangle configured by target and two measurement points. Suggested target positioning error formula are confirmed by simulation using the Gaussian distribution.

Effect of orientation, interval size, target location on interpolation estimates on CRT display. (CRT 표시장치에서 내삽 추정치에 대한 방향, 크기, 위치의 효과)

  • 노재호
    • Journal of the Ergonomics Society of Korea
    • /
    • v.9 no.1
    • /
    • pp.35-42
    • /
    • 1990
  • This study is concerned with the accuracy, of error with which subjects can interpolate the location of a target between two graduation markers with 4 orientations and 6 sizes CRT display. Stimuli were graphic images on CRT with a linear, end-markec, ungraduated scales having a target. The location of a target is estimated in units over te range 1-99. Smallest error of estimates was at the near ends and middle of the base-line. The median error was less than 2 units, modal error was 1, and the most error (; 99.7%) was within 10. A proper size to make an minimum error in interpolation exists such that size 400 pixels. Interpolation estimation is shown to be affected by the size, location and interaction (orientation x location, size x location). The accuracy, interpolation performance are discussed in relation to absolute error associated with visual performance.

  • PDF

The estimation of first order derivative phase error using iterative algorithm in SAR imaging system (SAR(Synthetic Aperture Radar)Imaging 시스템에서 제안 알고리즘의 반복수행을 통한 위상오차의 기울기 추정기법 연구)

  • 김형주;최정희
    • Proceedings of the IEEK Conference
    • /
    • 2000.11a
    • /
    • pp.505-508
    • /
    • 2000
  • The success of target reconstruction in SAR(Synthetic Aperture Radar) imaging system is greatly dependent on the coherent detection. Primary causes of incoherent detection are uncompensated target or sensor motion, random turbulence in propagation media, wrong path in radar platform, and etc. And these appear as multiplicative phase error to the echoed signal, which consequently, causes fatal degradations such as fading or dislocation of target image. In this paper, we present iterative phase error estimation scheme which uses echoed data in all temporal frequencies. We started with analyzing wave equation for one point target and extend to overall echoed data from the target scene - The two wave equations governing the SAR signal at two temporal frequencies of the radar signal are combined to derive a method to reconstruct the complex phase error function. Eventually, this operation attains phase error correction algorithm from the total received SAR signal. We verify the success of the proposed algorithm by applying it to the simulated spotlight-mode SAR data.

  • PDF

A Study on Beam Error Method of Coherent Interference Signal Estimation using Optimum Covariance Weight Vector (최적 공분산 가중 벡터를 이용한 상관성 간섭 신호 추정의 빔 지향 오차)

  • Cho, Sung Kuk;Lee, Jun Dong;Jeon, Byung Kook
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.10 no.4
    • /
    • pp.53-61
    • /
    • 2014
  • In this paper, we proposed covariance weight matrix using SPT matrix in order to accurate target estimation. We have estimated a target using modified covariance matrix and beam steering error method. We have minimized beam steering error in order to estimation desired a target. This method obtain optimum covariance weight using modified SPT matrix. This paper of proposal method is showed good performance than general method. We updated a weight of covariance matrix using modified SPT matrix. We obtain optimum covariance matrix weight to application beam steering error method in order to beam steering toward desired target. Through simulation, we showed that compare proposal method with general method. It have improved resolution of estimation target to good performance more proposed method than general method.

Phase Error Decrease Method for Target Direction Detection Improvement (표적 방향 탐지 향상을 위한 위상 오차 감소 방법)

  • Lee, Min-Soo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.14 no.1
    • /
    • pp.7-13
    • /
    • 2021
  • This paper proposes a method to minimize the target's direction detection error using RADAR. The radar system cannot accurately detect the target direction due to the phase error of he received signal. The proposed method of this study obtains a phase by applying an root mean square to each antenna incident signal, and reduces the phase error by using an optimal signal to noise ratio. In the simulation result, the probability of detecting the target direction is the best when the antenna spacing is half wavelength. The conventional method of direction detection probability 10-1.7 and the proposed method is 10-3.3. The target detection direction of the existing method represents [-8°,8°] with an error of 2 degrees. The target detection direction of the proposed method is shown in [-10°,10°], and all target directions are accurately detected. In the future, There is need for a method to reduce the phase error even though the resolution decrease.

Error Analysis Study on the Veering of Marine Target and the Midcourse Guidance of Anti-ship Missile (해상표적의 변침과 대함유도탄의 중기유도 오차분석 연구)

  • Kim, In-Soo
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.23 no.6
    • /
    • pp.582-590
    • /
    • 2020
  • This paper presents the results of new error analysis on the veering of marine target with the concept of frequency of occurrence, and shows how to apply the midcourse guidance errors of anti-ship missile. The veering error would be a dominant factor in the midcourse guidance errors with flight time increase. This study suggests the reasonable application method of the veering error based on the characteristics of abnormal error, and describes the tailoring method including trade-off between the midcourse guidance range of veering target and the value of frequency of occurrence on veering error.

A Calibration Technique and its Error Analysis for the Position of Seabed Sonar Target (해저고정 소나표적의 위치교정기법과 오차해석)

  • 이상국;이용곤
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.6 no.3
    • /
    • pp.15-21
    • /
    • 2003
  • This paper contains a precise calibration technique for the position of seabed acoustic target and theoretical error analysis of calibration results. The target is deployed on seabed as a standalone transponder. The purpose of target is performing accuracy test for active sonar as well as position calibration itself. For the position calibration, relative range between target and test vessel should be measured using target's transponder function. The relative range data combined with vessel position can be converted into a estimated position of target by the application of nonlinear LSE method. The error analysis of position calibration was divided into two stages. One is for relative range estimator and the other for target position estimator. Numerical simulations for position calibration showed good matching between results and developed CRLB.

A Study on the Performance Digital Beamforming using Antenna Error Correction and Modified Optimum Weight for Improved Signal Estimation (향상된 신호 추정을 위한 안테나 오차 보정 과 수정된 최적 가중치를 이용한 디지털 빔 형성 성능 분석에 관한 연구)

  • Cho, Sung Kuk;Lee, Jun Dong;Yang, Gill Mo
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.10 no.4
    • /
    • pp.63-70
    • /
    • 2014
  • Method a target estimation in spatial are mobile wireless communication using network cell and GPS. It have much error that mobile wireless communication depend on cell size. GPS method can't find a target in shadow and inner area. In this paper, we estimate a target as direction of arrival method using adaptive array antenna system. Adaptive array antenna system can obtain desired signal to remove other signal This paper studied digital beamforming method in order to estimation a target. Proposed method is modified optimum weight and antenna error correction to estimation an optimal receive signal. Digital beamforming method decided a signal phase and amplitude from received signal on array antenna element. But if it is not to do error correction of received signal, system performance have decreased. Firstly, we proposed modified optimum weight in order to finding desired target. Secondly, we are error correction of antenna incident signals by optimal weight before digital beamforming method. Thirdly, throughly simulation, we showed that system performance of proposed method compare proposal method with general method. It have improved resolution of estimation target to good performance more proposed method than general method.

A Study on Super Resolution Optimum Beam Steering Pattern for Improvement Moving Target Estimation Accuracy (이동 목표물 추정 정확도를 향상시키기 위한 고 분해능 최적 빔 지향 패턴에 관한 연구)

  • Cho, Sung Kuk;Jeon, Byung Kook;Yang, Gill Mo
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.10 no.4
    • /
    • pp.71-78
    • /
    • 2014
  • Method a target estimation in spatial are mobile wireless communication using network cell and GPS. It have much error that mobile wireless communication depend on cell size. GPS method can't find a target in shadow and inner area. In this paper, we estimate a target as direction of arrival method using adaptive array antenna system. Adaptive array antenna system can obtain desired signal to remove other signal This paper studied digital beamforming method in order to estimation a target. Proposed method is modified optimum weight and antenna error correction to estimation an optimal receive signal. Digital beamforming method decided a signal phase and amplitude from received signal on array antenna element. But if it is not to do error correction of received signal, system performance have decreased. Firstly, we proposed modified optimum weight in order to finding desired target. Secondly, we are error correction of antenna incident signals by optimal weight before digital beamforming method. Thirdly, throughly simulation, we showed that system performance of proposed method compare proposal method with general method. It have improved resolution of estimation target to good performance more proposed method than general method.