• 제목/요약/키워드: target

검색결과 25,027건 처리시간 0.042초

시각탐색에서 표적 유형과 망막 이심율 효과 (Effects of target types and retinal eccentricity on visual search)

  • 신현정;권오영
    • 인지과학
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    • 제14권3호
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    • pp.1-11
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    • 2003
  • 정지/운동하는 배경자극들 속에서 정지/운동하는 표적을 탐지하는 데 있어서 표적 유형과 망막 이심율의 효과를 알아보기 위해서 두 가지 실험을 수행하였다. 두 실험 모두 시각탐색과제를 사용하였다. 망막 이심율은 1.6$^{\circ}$ 단위로 커지는 5개의 동심원으로 구분하였으며, 표적은 배경자극과 방위차원에서 차이나는 방위 표적과 세부특정에서 차이나는 세부특정 표적이었다. 실험 l에서는 표적과 배경자극이 모두 정지되어있는 상황에서의 탐색을 다루었다. 그 결과 표적 유형과 망막 이심율 사이에 상호작용이 있었다. 정지상황에서 방위 표적은 망막 이심율의 영향을 별로 받지 않는 반면에, 세부특정 표적은 망막 이율이 증가함에 따라서 탐지시간이 일관성 있게 증가하였다. 표적과 배경자극이 모두 운동하는 상황인 실험 2 에서도 둘 사이의 상호작용이 나타냈으나, 그 이유는 실험 1과 극적인 대조를 이루었다. 즉, 운 동 상황에서 방위 표적은 망막 이심율이 증가함에 따라서 탐지시간이 일관성 있게 감소하는 반면, 세부 특징 표적은 망막 이심율의 영향을 거의 받지 않았다. 두 실험의 결과를 항공기나 자동차의 운동과 같은 현실상황과 관련된 합의와 문제점 그리고 향후 연구방향을 논의하였다.

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Extraction of Infrared Target based on Gaussian Mixture Model

  • Shin, Do Kyung;Moon, Young Shik
    • IEIE Transactions on Smart Processing and Computing
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    • 제2권6호
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    • pp.332-338
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    • 2013
  • We propose a method for target detection in Infrared images. In order to effectively detect a target region from an image with noises and clutters, spatial information of the target is first considered by analyzing pixel distributions of projections in horizontal and vertical directions. These distributions are represented as Gaussian distributions, and Gaussian Mixture Model is created from these distributions in order to find thresholding points of the target region. Through analyzing the calculated Gaussian Mixture Model, the target region is detected by eliminating various backgrounds such as noises and clutters. This is performed by using a novel thresholding method which can effectively detect the target region. As experimental results, the proposed method has achieved better performance than existing methods.

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원가기획시스템의 실무수준과 성과간의 관련성에 관한 실증연구 (Relationship between Target Costing Practices and Organizational Performance : An Empirical study)

  • 육근효
    • 품질경영학회지
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    • 제31권3호
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    • pp.1-18
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    • 2003
  • Target Costing research has a long history in the study of management control systems. However, there is very little published empirical analysis studies on Target Costing. This study investigate the impact of Target Costing practices on organizational performance. This study uses survey responses from executive at 125 Target Costing practicing firms to better understand the benefits that firms have experienced through Target Costing adoption and whether a more comprehensive implementation is worthwhile. The research results demonstrate that Target Costing has a positive and significant relationship with low cost, efficiency of R&D, and interaction facilitation. In particular, there is significant and positive relationship between organizational structure and performance. This study indicate that Target Costing is a vital management strategy to build and sustain competitive advantage.

Robust Target Model Update for Mean-shift Tracking with Background Weighted Histogram

  • Jang, Yong-Hyun;Suh, Jung-Keun;Kim, Ku-Jin;Choi, Yoo-Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권3호
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    • pp.1377-1389
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    • 2016
  • This paper presents a target model update scheme for the mean-shift tracking with background weighted histogram. In the scheme, the target candidate histogram is corrected by considering the back-projection weight of each pixel in the kernel after the best target candidate in the current frame image is chosen. In each frame, the target model is updated by the weighted average of the current target model and the corrected target candidate. We compared our target model update scheme with the previous ones by applying several test sequences. The experimental results showed that the object tracking accuracy was greatly improved by using the proposed scheme.

Compressed Sensing-based Multiple-target Tracking Algorithm for Ad Hoc Camera Sensor Networks

  • Lu, Xu;Cheng, Lianglun;Liu, Jun;Chen, Rongjun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권3호
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    • pp.1287-1300
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    • 2018
  • Target-tracking algorithm based on ad hoc camera sensor networks (ACSNs) utilizes the distributed observation capability of nodes to achieve accurate target tracking. A compressed sensing-based multiple-target tracking algorithm (CSMTTA) for ACSNs is proposed in this work based on the study of camera node observation projection model and compressed sensing model. The proposed algorithm includes reconfiguration of observed signals and evaluation of target locations. It reconfigures observed signals by solving the convex optimization of L1-norm least and forecasts node group to evaluate a target location by the motion features of the target. Simulation results show that CSMTTA can recover the subtracted observation information accurately under the condition of sparse sampling to a high target-tracking accuracy and accomplish the distributed tracking task of multiple mobile targets.

표적 크기추정 기술 기반의 CCD 영상 표적 정밀 요격 성능 개선 연구 (A Study on the Target Precision Intercept Algorithm based on the Target Size Estimation at CCD Image Sequence)

  • 정윤식;노신백
    • 제어로봇시스템학회논문지
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    • 제21권1호
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    • pp.52-58
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    • 2015
  • In this paper, The ET-MBEF algorithm is presented for CCD imaging seeker. At the imaging seeker, target size information is important factor for accurate tracking. The MBEF algorithm was proposed to estimate target size at IIR seeker. However, the MBEF algorithm can't be applied at CCD imaginary target size estimation. In order to overcome the problem, we propose ET-MBEF algorithm which based on ET (Edge Template) and MBEF algorithm. The performance of proposed method is tested at target intercept scenario. The experiment results show that the proposed algorithm has the accurate target intercept performance.

표적의 부분가림이 존재하는 환경에서 견실한 추적을 위한 영상 표적 탐지, 추적 알고리듬 연구 (A Study of Image Target Detection and Tracking for Robust Tracking in an Occluded Environment)

  • 김용;송택렬
    • 제어로봇시스템학회논문지
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    • 제16권10호
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    • pp.982-990
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    • 2010
  • In a target tracking system using image information from a CCD (Charged Couple Device) or an IIR (Imaging Infra-red) sensor, occluded targets can result in track losses. If the target is occlued by background objects such as buildings or trees, probability of track existence will be reduced sharply and track will be terminated due to track maintenance algorithms. This paper proposes data association algorithm based on target existence for the robust tracking performance. we suggest the HPDA (Highest Probability Data Association) algorithm based on target existence and the tracking performance is compared with the established method based on target perceivability. Image tracking simulation that utilizes virtual 3D images and real IR images is employed to evaluate the robustness of the proposed tracking algorithm.

정밀 거리-속도 모사 기능을 갖는 레이더 반사 신호 모의장치 (Radar Echo Signal Simulation Equipment with a Precise Range-velocity Control Capability)

  • 한일탁;김종만;김완규;이민준
    • 한국군사과학기술학회지
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    • 제13권6호
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    • pp.1139-1146
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    • 2010
  • Simulated target generators are used to evaluate the various radar performance. Using the radar parameters such as target range(time delay), doppler frequency, target RCS, simulated target generator can be developed. Especially moving targets are simulated by control time delay and update target signal intensive for target range. Base on this concepts, in this paper, simulated target generators are designed and developed for X-band Radar performance test. Developed equipment is evaluated its performance and then tested with X-band Radar. This paper presents these design, development, and test results of developed target generator.

Infrared Target Extraction Using Weighted Information Entropy and Adaptive Opening Filter

  • Bae, Tae Wuk;Kim, Hwi Gang;Kim, Young Choon;Ahn, Sang Ho
    • ETRI Journal
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    • 제37권5호
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    • pp.1023-1031
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    • 2015
  • In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

Pharmacodynamic principles and target concentration intervention

  • Holford, Nick
    • Translational and Clinical Pharmacology
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    • 제26권4호
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    • pp.150-154
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    • 2018
  • This tutorial reviews the principles of dose individualisation with an emphasis on target concentration intervention (TCI). Once a target effect is chosen then pharmacodynamics can predict the target concentration and pharmacokinetics can predict the target dose to achieve the required response. Dose individualisation can be considered at three levels: population, group and individual. Population dosing, also known as fixed dosing or "one size fits all" is often used but is poor clinical pharmacology; group dosing uses patient features such as weight, organ function and comedication to adjust the dose for a typical patient; individual dosing uses observations of patient response to inform about pharmacokinetic and pharmacodynamics in the individual and use these individual differences to individualise dose.