• Title/Summary/Keyword: Forward target method

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Small Target Detection with Clutter Rejection using Stochastic Hypothesis Testing

  • Kang, Suk-Jong;Kim, Do-Jong;Ko, Jung-Ho;Bae, Hyeon-Deok
    • Journal of Korea Multimedia Society
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    • v.10 no.12
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    • pp.1559-1565
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    • 2007
  • The many target-detection methods that use forward-looking infrared (FUR) images can deal with large targets measuring $70{\times}40$ pixels, utilizing their shape features. However, detection small targets is difficult because they are more obscure and there are many target-like objects. Therefore, few studies have examined how to detect small targets consisting of fewer than $30{\times}10$ pixels. This paper presents a small target detection method using clutter rejection with stochastic hypothesis testing for FLIR imagery. The proposed algorithm consists of two stages; detection and clutter rejection. In the detection stage, the mean of the input FLIR image is first removed and then the image is segmented using Otsu's method. A closing operation is also applied during the detection stage in order to merge any single targets detected separately. Then, the residual of the clutters is eliminated using statistical hypothesis testing based on the t-test. Several FLIR images are used to prove the performance of the proposed algorithm. The experimental results show that the proposed algorithm accurately detects small targets (Jess than $30{\times}10$ pixels) with a low false alarm rate compared to the center-surround difference method using the receiver operating characteristics (ROC) curve.

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Tracing Algorithm for Intelligent Snake-like Robot System

  • Choi, Woo-Kyung;Kim, Seong-Joo;Jeon, Hong-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.486-491
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    • 2005
  • There come various types of robot with researches for mobile robot. This paper introduces the multi-joint snake robot having 16 degree of freedom and composing of eight-axis. The biological snake robot uses the forward movement friction and the proposed artificial snake robot uses the un-powered wheel instead of the body of snake. To determine the enable joint angle of each joint, the controller inputs are considered such as color and distance using PC Camera and ultra-sonic sensor module, respectively. The movement method of snake robot is sequential moving from head to tail through body. The target for movement direction is decided by a certain article be displayed in the PC Camera. In moving toward that target, if there is any obstacle then the snake robot can avoid by itself. In this paper, we show the method of snake robot for tracing the target with experiment.

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Through-field Investigation of Stray Light for the Fore-optics of an Airborne Hyperspectral Imager

  • Cha, Jae Deok;Lee, Jun Ho;Kim, Seo Hyun;Jung, Do Hwan;Kim, Young Soo;Jeong, Yumee
    • Current Optics and Photonics
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    • v.6 no.3
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    • pp.313-322
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    • 2022
  • Remote-sensing optical payloads, especially hyperspectral imagers, have particular issues with stray light because they often encounter high-contrast target/background conditions, such as sun glint. While developing an optical payload, we usually apply several stray-light analysis methods, including forward and backward analyses, separately or in combination, to support lens design and optomechanical design. In addition, we often characterize the stray-light response over a full field to support calibration, or when developing an algorithm to correct stray-light errors. For this purpose, we usually use forward analysis across the entire field, but this requires a tremendous amount of computational time. In this paper, we propose a sequence of forward-backward-forward analyses to more effectively investigate the through-field response of stray light, utilizing the combined advantages of the individual methods. The application is an airborne hyperspectral imager for creating hyperspectral maps from 900 to 1700 nm in a 5-nm-continuous band. With the proposed method, we have investigated the through-field response of stray light to an effective accuracy of 0.1°, while reducing computation time to 1/17th of that for a conventional, forward-only stray-light analysis.

Contour Plots of Objective Functions for Feed-Forward Neural Networks

  • Oh, Sang-Hoon
    • International Journal of Contents
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    • v.8 no.4
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    • pp.30-35
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    • 2012
  • Error surfaces provide us with very important information for training of feed-forward neural networks (FNNs). In this paper, we draw the contour plots of various error or objective functions for training of FNNs. Firstly, when applying FNNs to classifications, the weakness of mean-squared error is explained with the viewpoint of error contour plot. And the classification figure of merit, mean log-square error, cross-entropy error, and n-th order extension of cross-entropy error objective functions are considered for the contour plots. Also, the recently proposed target node method is explained with the viewpoint of contour plot. Based on the contour plots, we can explain characteristics of various error or objective functions when training of FNNs proceeds.

Laboratory Test Method for the Forward Motion Compensation of Airborne Camera (항공용 카메라 전방운동 보상기능의 실험실 입증방안)

  • Song, Dae-Buem;Yoon, Yong-Eun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.4
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    • pp.507-512
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    • 2012
  • Image blurring in airborne camera can be prevented through timely actuation of LOS(Line of Sight) into the opposite direction to the aircraft advancement, i.e. FMC(Forward motion compensation). Performance verification of FMC requires installation of camera to the aircraft. However, in many ways the verification process has little choice but to be implemented in the laboratory. In this paper verification method of FMC performance in the laboratory is introduced. With collimator target installed in the known reference position image obtained by actual mission plan naturally displays image blurring as well as LOS displacement by FMC effect. Through comparison of the amount of those image blurring and LOS displacement to the equivalent image distortion expected by the application of the FMC reference command can the performance be verified. In this paper we propose a new verification method of FMC performance in laboratory along with generalized solution of FMC reference command, and assess the validity of our proposition.

Research about Intelligent Snake Robot (지능형 뱀 로봇에 관한 연구)

  • Kim, Seong-Joo;Kim, Jong-Soo;Jeon, Hong-Tae
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.1
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    • pp.70-75
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    • 2003
  • There come various types of robot with researches for mobile robot. This paper introduces the multi-joint snake robot having 16 degree of freedom and composing of eight-axis. The biological snake robot uses the forward movement friction and the proposed artificial snake robot uses the un-powered wheel instead of the body of snake. To determine the enable joint angle of each joint, the controller inputs are considered such as color and distance using PC Camera and ultra-sonic sensor module, respectively. The movement method of snake robot is sequential moving from head to tail through body. The target for movement direction is decided by a certain article be displayed in the PC Camera. In moving toward that target, if there is any obstacle then the snake robot can avoid by itself. In this paper, we show the method of snake robot for tracing the target with experiment.

Analysis of Previous Make-up Study (화장에 관한 기존연구 유형의 분석)

  • 백경진;김미영
    • The Research Journal of the Costume Culture
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    • v.12 no.1
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    • pp.182-198
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    • 2004
  • The purpose of this study was to analyze the previous make-up studies. A number of publications and journals were reviewed and analyzed carefully. The results of review and analysis were as follows: There were many different subjects in make-up studies and They can be divided into ten types : cosmetics purchase behavior, change of make-up culture and comparison, make-up trend by era, cosmetics industry's standing of today and strategy, art trend in make-up, brand preference of cosmetics, make up attitude, recognition about imported cosmetics and purchase behavior, color preference of cosmetics, the relationship between self-concept and make-up. In general, the cosmetic purchase behavior studies are conducted most actively. According to result that analyze existent study, special duality of cosmetics purchase action appears very variously according to standard of classification of study target and study target. But, study target and method of study are not various, and purchase behavior study collected with make-un and clothes is yew lacking. Therefore, in this study, wished to discover problem of virtue study because analyzes studies about previous make-up and present forward study direction.

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Design and Realization of a Digital PV Simulator with a Push-Pull Forward Circuit

  • Zhang, Jike;Wang, Shengtie;Wang, Zhihe;Tian, Lixin
    • Journal of Power Electronics
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    • v.14 no.3
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    • pp.444-457
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    • 2014
  • This paper presents the design and realization of a digital PV simulator with a Push-Pull Forward (PPF) circuit based on the principle of modular hardware and configurable software. A PPF circuit is chosen as the main circuit to restrain the magnetic biasing of the core for a DC-DC converter and to reduce the spike of the turn-off voltage across every switch. Control and I/O interface based on a personal computer (PC) and multifunction data acquisition card, can conveniently achieve the data acquisition and configuration of the control algorithm and interface due to the abundant software resources of computers. In addition, the control program developed in Matlab/Simulink can conveniently construct and adjust both the models and parameters. It can also run in real-time under the external mode of Simulink by loading the modules of the Real-Time Windows Target. The mathematic models of the Push-Pull Forward circuit and the digital PV simulator are established in this paper by the state-space averaging method. The pole-zero cancellation technique is employed and then its controller parameters are systematically designed based on the performance analysis of the root loci of the closed current loop with $k_i$ and $R_L$ as variables. A fuzzy PI controller based on the Takagi-Sugeno fuzzy model is applied to regulate the controller parameters self-adaptively according to the change of $R_L$ and the operating point of the PV simulator to match the controller parameters with $R_L$. The stationary and dynamic performances of the PV simulator are tested by experiments, and the experimental results show that the PV simulator has the merits of a wide effective working range, high steady-state accuracy and good dynamic performances.

Efficient Preprocessing Method for Binary Centroid Tracker in Cluttered Image Sequences (복잡한 배경영상에서 효과적인 전처리 방법을 이용한 표적 중심 추적기)

  • Cho, Jae-Soo
    • Journal of Advanced Navigation Technology
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    • v.10 no.1
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    • pp.48-56
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    • 2006
  • This paper proposes an efficient preprocessing technique for a binary centroid tracker in correlated image sequences. It is known that the following factors determine the performance of the binary centroid target tracker: (1) an efficient real-time preprocessing technique, (2) an exact target segmentation from cluttered background images and (3) an intelligent tracking window sizing, and etc. The proposed centroid tracker consists of an adaptive segmentation method based on novel distance features and an efficient real-time preprocessing technique in order to enhance the distinction between the objects of interest and their local background. Various tracking experiments using synthetic images as well as real Forward-Looking InfraRed (FLIR) images are performed to show the usefulness of the proposed methods.

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Target Detection Using Texture Features and Neural Network in Infrared Images (적외선영상에서 질감 특징과 신경회로망을 이용한 표적탐지)

  • Sun, Sun-Gu
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.47 no.5
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    • pp.62-68
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    • 2010
  • This study is to identify target locations with low false alarms on thermal infrared images obtained from natural environment. The proposed method is different from the previous researches because it uses morphology filters for Gabor response images instead of an intensity image in initial detection stage. This method does not need precise extracting a target silhouette to distinguish true targets or clutters. It comprises three distinct stages. First, morphological operations and adaptive thresholding are applied to the summation image of four Gabor responses of an input image to find out salient regions. The locations of extracted regions can be classified into targets or clutters. Second, local texture features are computed from salient regions of an input image. Finally, the local texture features are compared with the training data to distinguish between true targets and clutters. The multi-layer perceptron having three layers is used as a classifier. The performance of the proposed method is proved by using natural infrared images. Therefore it can be applied to real automatic target detection systems.