Abstract: The influence of converter faults to the system is introduced and the fault detection method based on wavelet transform and neural network is proposed in this paper. The fault information can be decomposed by wavelet transform, then the fault eigenvectors can be extracted and put into neural network for training and testing. Finally the neural network outputs specific codes, and thus the fault location and fault components of converters are confirmed, which lays the foundation for the fault-tolerant operation control of converters. Simulation and experimental results show the correctness and effectiveness of the method.
Abstract: A measuring system of vehicle distance is proposed on the basis of binocular vision using location information of the vehicle logo. The spatial location of the target vehicle can be obtained by the pixel coordinates in the image plane due to the logo is sited at the central axis of the vehicle. The camera calibration algorithm is accomplished by conversion relation matrix between the world coordinate system and the image coordinate. And then the binocular logo image pairs are matched. Finally, the distance of the target vehicle is calculated. The simulation experiments have been done and the results show that the proposed method of distance measurement has better performance with rapid processing and higher accuracy.
Abstract: Vacuum circuit breaker becomes more and more complicated, integrated, high-speed and intellectualized. To insure vacuum circuit breaker in its good conditions, the function of fault diagnosis gets more important than before in the process of repairing. This paper designed and developed a network fault diagnosis system based on PROFINET and B/S (Browser/Server) frame through the analysis of the need of fault diagnosis. Taking good use of testing information and diagnosis rules, the system realized open and distributed diagnosing process, and provided a flat of sharing information, which is the technique basis of combining testing and diagnosing. During design, we use Kingview as developing software. It is proved in LAN that the system can utilize present diagnosis rules in database to diagnose fault distributed.
Abstract: This paper presents a system developed for online fatigue monitoring for steam turbine rotor in power plants. The system converts the plant transients to temperature and thermal stress responses using the analytical models modified by FEM. The torsional vibration caused by the possible sub-synchronous oscillation (SSO) phenomenon in power networks has been analyzed. The fatigue damage caused by thermal stress and SSO is studied based on the stress analysis and fatigue cumulation. The fatigue usage factor is computed using the rainﬂow cycle counting algorithm. The method can provide useful information in support of the unit’s life cycle management and efficient.
Abstract: Moving object detection is the basic of video applications such as computer vision, object recognition and tracking, surveillance security etc. Background subtraction and symmetrical differencing are the popular methods of motion detection. The main idea of them is to compare the current video frame with a specified background image or a background model or the next video frame. For background subtraction, the obtaining of initialization is crucial and many methods have been employed, so it is necessary to model background to adapt the changes of background. In this paper, the single gaussian modeling as the initialization background model combined with an improved linear alternate background updating method is proposed. And then, a novel moving human detection method which employs background subtraction and symmetrical differencing based on rgb color difference model is presented. The experimental results show that the detection method can detect moving human effectively and real-time.
Abstract: This paper presents a novel method for the calibration of camera and projector based on discrete computation, which uses a linear moving chessboard and project plane to get a calibration database for camera and projector. The camera database contains multi-layers data of the captured chessboard corners and their corresponding practical coordinates in the system. Then by using this database and interpolation algorithm, we can calculate the accurate position for each given pixel position in the captured image. After this we change the chessboard with a white scene and project a chessboard image to the plane. By capturing the projected image and computing the practical position for the corners in the image, we can get a relationship between practical coordinates and the projected image pixels. So another database for the project image and the practical coordinates is established. By using these two databases, we can define the light line for the pixels in a camera captured image and projected image, which can be used for 3D scanning system and other industrial systems, like mask-image projection stereo lithography rapid prototyping system.
Abstract: This paper aims at investigating a method for tackling the problem of automated fabric defect detection. A new scheme for defect detection using Gabor filters was proposed. In the experiment, texture features is extracted using Gabor filters. The proposed method would automatically segment defects from the regular texture. The experimental results showed the effectiveness of the proposed detection scheme.
Abstract: Take insufficiency of classical velocity measurement methods into consideration, this paper introduces a method which has a good test accuracy in a wide range, fixed sampling period M/T method, to determine velocity and position information of the encoder. Firstly, its measurement principle is analyzed in detail through logic and timing relationship. Then realization of every module is achieved with VHDL. Finally, ModelSim is used to simulation and test to verify the correctness of the method. In the future, it can be widely used in practical applications.
Abstract: In order to monitor tire pressure changes all the time, prevention of blowout and other causes of traffic accidents. By using of Single chip microcomputer(MCU) multitasking technology design of control system for the indirect tire pressure monitoring model. Through the photoelectric sensors to collect four groups tire speed information and develop a series of algorithms and determination method to judge the working state of the tires. It realizes the abnormal tire pressure alarm, and has made up the traditional indirect tire pressure monitoring method insufficiency. Draw the following conclusion: Through use of MCU multitasking technology, taking the radius of the changes caused by the tires pressure changes before blowout for comparison and analysis, getting several situations of tire burst judging method, and producing instruction and alarm that plays the purpose of real-time monitoring of tire blowout to prevent the sudden traffic accidents.
Abstract: The scheme adopts computer testing technology, virtual instrument and virtual system technology to realize the automatic detection for heading and attitude signal conversion equipment of aircraft. It greatly improves the test efficiency. Test time was reduced from 30 minutes to 3 minutes. Based on wavelet analysis and hierarchical decision, program module of connected line identification is design and it improves the reliability of program running. Noisy signals are de-noised by automatic zoom function of wavelet transform and that solves the interference problems of AC power supply.