• Title/Summary/Keyword: structure detection

Search Result 2,044, Processing Time 0.028 seconds

Rotation Invariant Real-time Face Detection Using Cascade Structure In Color Images (단계형 구조를 이용한 실시간 얼굴 탐지 시스템)

  • Kim, Seung-Goo;Kim, Hye-Soo;Ko, Sung-Jea
    • Proceedings of the IEEK Conference
    • /
    • 2007.07a
    • /
    • pp.339-340
    • /
    • 2007
  • Face detection plays an important role in HCI and face recognition. In this paper, we propose a rotation-invariant real-time face detection algorithm for color images in complex background. It consists of four processing step: (1) motion detection, (2) skin color region filler, (3) Eyemap detector for rotated face, and (4) Adaboost face classifier. This system has been tested in in-door environments, such as office and achieves over 95% detection rate.

  • PDF

A Non-contact Detection Method for Smelting in Submerged Arc Furnace based on Magnetic Field Radiation

  • Liu, WeiLing;Chang, XiaoMing
    • Journal of Magnetics
    • /
    • v.21 no.2
    • /
    • pp.204-208
    • /
    • 2016
  • This paper demonstrates the key parameter detection for smelting of submerged arc furnace (SAF) based on magnetic field radiation. A magnetic field radiation model for the inner structure of SAF is established based on relative theory of electromagnetic field. A simple equipment of 3D magnetic field detection system is developed by theoretical derivation and simulation. The experiments are carried out under the environment of industrial field and AC magnetic field generated by electrode currents and molten currents in the furnace is reflected outside of the furnace. The experimental results show that the key parameters of smelting including the position of electrode tip, the length of electric arc, and the liquid level of molten bath can be achieved. The computed tomography for SAF can be realized by the detection for smelting.

Signal processing based damage detection in structures subjected to random excitations

  • Montejo, Luis A.
    • Structural Engineering and Mechanics
    • /
    • v.40 no.6
    • /
    • pp.745-762
    • /
    • 2011
  • Damage detection methodologies based on the direct examination of the nonlinear-nonstationary characteristics of the structure dynamic response may play an important role in online structural health monitoring applications. Different signal processing based damage detection methodologies have been proposed based on the uncovering of spikes in the high frequency component of the structural response obtained via Discrete Wavelet transforms, Hilbert-Huang transforms or high pass filtering. The performance of these approaches in systems subjected to different types of excitation is evaluated in this paper. It is found that in the case of random excitations, like earthquake accelerations, the effectiveness of such methodologies is limited. An alternative damage detection approach using the Continuous Wavelet Transform (CWT) is also evaluated to overcome this limitation. Using the CWT has the advantage that the central frequencies at which it operates can be defined by the user while the frequency bands of the detail functions obtained via DWT are predetermined by the sampling period of the signal.

Face Detection using Template Matching and Ellipse Fitting (템플릿과 타원정보를 이용한 얼굴검출)

  • Jung, Tae-Yun;Kim, Hyun-Sool;Kang, Woo-Seok;Park, Sang-Hui
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.48 no.11
    • /
    • pp.1472-1475
    • /
    • 1999
  • This paper proposes a new detection method of human faces in grey scale images with cluttered background using a facial template and elliptical structure of the human head. Face detection technique can be applied in many areas of image processing such as face recognition, composition and computer graphics, etc. Until now, many researches about face detection have been done, and applications in more complicated conditions are increasing. The existing technique proposed by Sirohey shows relatively good performance in image with cluttered background, but can apply only to image with one face and needs much computation time. The proposed method is designed to reduce complexity and be applied even in the image with several faces by introducing template matching as preprocess. The results show that the proposed method produces more correct detection rate and needs less computation time than the existing one.

  • PDF

A Study on Implementation of Out-of-Step Detection Algorithm using VHDL (VHDL을 이용한 동기탈조 검출 알고리즘 구현에 관한 연구)

  • Kim, Chul-Hwan;Kwon, O-Sang
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.55 no.5
    • /
    • pp.179-184
    • /
    • 2006
  • In a power system, an out-of-step condition causes a variety of risk such as serious damage to system elements, tripping of loads and generators, mal-operation of relays, etc. Therefore, it is very important to detect the out-of- step condition and take a proper measure. This paper presents a study on implementation of out-of-step detection algorithm using VHDL(Very high speed Hardware Description Language). The structure of out-of-step detection algorithm is analyzed for development of out-of-step detection relay on the FPGA(Field Programmable Gate Array). The out-of-step algorithm is separated to 4 parts: DFT IP, complex power calculation IP, out-of-step detection IP, control unit. Each parts are developed and simulated by using VHDL.

Aircraft Recognition from Remote Sensing Images Based on Machine Vision

  • Chen, Lu;Zhou, Liming;Liu, Jinming
    • Journal of Information Processing Systems
    • /
    • v.16 no.4
    • /
    • pp.795-808
    • /
    • 2020
  • Due to the poor evaluation indexes such as detection accuracy and recall rate when Yolov3 network detects aircraft in remote sensing images, in this paper, we propose a remote sensing image aircraft detection method based on machine vision. In order to improve the target detection effect, the Inception module was introduced into the Yolov3 network structure, and then the data set was cluster analyzed using the k-means algorithm. In order to obtain the best aircraft detection model, on the basis of our proposed method, we adjusted the network parameters in the pre-training model and improved the resolution of the input image. Finally, our method adopted multi-scale training model. In this paper, we used remote sensing aircraft dataset of RSOD-Dataset to do experiments, and finally proved that our method improved some evaluation indicators. The experiment of this paper proves that our method also has good detection and recognition ability in other ground objects.

Triqubit-State Measurement-Based Image Edge Detection Algorithm

  • Wang, Zhonghua;Huang, Faliang
    • Journal of Information Processing Systems
    • /
    • v.14 no.6
    • /
    • pp.1331-1346
    • /
    • 2018
  • Aiming at the problem that the gradient-based edge detection operators are sensitive to the noise, causing the pseudo edges, a triqubit-state measurement-based edge detection algorithm is presented in this paper. Combing the image local and global structure information, the triqubit superposition states are used to represent the pixel features, so as to locate the image edge. Our algorithm consists of three steps. Firstly, the improved partial differential method is used to smooth the defect image. Secondly, the triqubit-state is characterized by three elements of the pixel saliency, edge statistical characteristics and gray scale contrast to achieve the defect image from the gray space to the quantum space mapping. Thirdly, the edge image is outputted according to the quantum measurement, local gradient maximization and neighborhood chain code searching. Compared with other methods, the simulation experiments indicate that our algorithm has less pseudo edges and higher edge detection accuracy.

Evaluations of AI-based malicious PowerShell detection with feature optimizations

  • Song, Jihyeon;Kim, Jungtae;Choi, Sunoh;Kim, Jonghyun;Kim, Ikkyun
    • ETRI Journal
    • /
    • v.43 no.3
    • /
    • pp.549-560
    • /
    • 2021
  • Cyberattacks are often difficult to identify with traditional signature-based detection, because attackers continually find ways to bypass the detection methods. Therefore, researchers have introduced artificial intelligence (AI) technology for cybersecurity analysis to detect malicious PowerShell scripts. In this paper, we propose a feature optimization technique for AI-based approaches to enhance the accuracy of malicious PowerShell script detection. We statically analyze the PowerShell script and preprocess it with a method based on the tokens and abstract syntax tree (AST) for feature selection. Here, tokens and AST represent the vocabulary and structure of the PowerShell script, respectively. Performance evaluations with optimized features yield detection rates of 98% in both machine learning (ML) and deep learning (DL) experiments. Among them, the ML model with the 3-gram of selected five tokens and the DL model with experiments based on the AST 3-gram deliver the best performance.

Abnormal Situation Detection on Surveillance Video Using Object Detection and Action Recognition (객체 탐지와 행동인식을 이용한 영상내의 비정상적인 상황 탐지 네트워크)

  • Kim, Jeong-Hun;Choi, Jong-Hyeok;Park, Young-Ho;Nasridinov, Aziz
    • Journal of Korea Multimedia Society
    • /
    • v.24 no.2
    • /
    • pp.186-198
    • /
    • 2021
  • Security control using surveillance cameras is established when people observe all surveillance videos directly. However, this task is labor-intensive and it is difficult to detect all abnormal situations. In this paper, we propose a deep neural network model, called AT-Net, that automatically detects abnormal situations in the surveillance video, and introduces an automatic video surveillance system developed based on this network model. In particular, AT-Net alleviates the ambiguity of existing abnormal situation detection methods by mapping features representing relationships between people and objects in surveillance video to the new tensor structure based on sparse coding. Through experiments on actual surveillance videos, AT-Net achieved an F1-score of about 89%, and improved abnormal situation detection performance by more than 25% compared to existing methods.

Miniaturized Sensor Interface Circuit for Respiration Detection System (호흡 검출 시스템을 위한 초소형 센서 인터페이스 회로)

  • Jo, Sung-Hun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.25 no.8
    • /
    • pp.1130-1133
    • /
    • 2021
  • In this paper, a miniaturized sensor interface circuit for the respiration detection system is proposed. Respiratory diagnosis is one of the main ways to predict various diseases. The proposed system consists of respiration detection sensor, temperature sensor, and interface circuits. Electrochemical type gas sensor using solid electrolytes is adopted for respiration detection. Proposed system performs sensing, amplification, analog-to-digital conversion, digital signal processing, and i2c communication. And also proposed system has a small form factor and low-cost characteristics through optimization and miniaturization of the circuit structure. Moreover, technique for sensor degradation compensation is introduced to obtain high accuracy. The size of proposed system is about 1.36 cm2.