Papers by Keyword: Infrared Imaging

Abstract: Aiming at the feature representation problem of infrared video, this paper presents an approach for bag of visual words model by considering the spatial and the temporal relations among the visual features. In this approach, motion mask image was generated based on motion history image, optical flow vector is mapping to visual code book. By using motion history value and motion energy value calculating the weighting coefficient, the BOVW was constructed based on angle voting. Experiments have demonstrated improved performances on motion feature representation in the infrared video.

Abstract: In this paper, infrared thermal wave NDT techniques are used for aircraft composites. After the infrared image is sharpened and the temperature field is analyzed, aircraft composite material defects can be diagnosed. Experiments show that the infrared NDT techniques can detect defects in aircraft composite image. Images and first-order differential image can be presented more clearly outline the process and temperature variations. Defect size and depth can also be measured. The best experiments are designed for different materials. After several experiments of the precise temperature calibration can be further studied. Defects can be interpreted intelligent.

Abstract: Along with the continuous development of Chinese economy, the power consumption continues to rise in China, and many high-voltage electric transmission lines are constantly put in construction. Among them, coupling capacitor is a major coupling device in the carrier communication of the power frequency high-voltage lines, and also a device that has been widely used for measuring and extracting electric energy, and controlling high-frequency protection in the electric power system. However, there are many problems in the application of coupling capacitor to high-voltage electric transmission lines. In the following, some common problems in the application of infrared imaging diagnosis technology to the coupling capacitor in high-voltage electric transmission lines are tested, so that the corresponding problems are found timely and accurately and also the right processing is made.

Abstract: There are two conventional techniques i.e. the approach based on structural testing and non-damaged detecting method, of which the former is partial to structural integrity analysis while the latter focuses on partial detection. The damage identification approach is discussed from the perspective of detection medium in the paper. And non-destructive testing in civil engineering (NDT-CE), of which the research status and existing issues are presented, can be attributed into three categories as following: one is based on the stress wave theory, such as impact-echo method, acoustic emission technique and ultrasonic pulse method; one employs the mechanism of electromagnetic wave propagation on behalf of GPR; one uses radiography as the medium, for instance, infrared imaging and computerized tomography. It is emphasized that ground penetrating radar (GPR) has been applied in practice and studied more and more, and moreover, the prospects in the field are provided.

Abstract: Three types of copper traces for PCBs were investigated: 1) 2.5 μm thin film lines (Ti;Cu;Ni) on aluminium and ceramic (Al₂O₃) substrates; 2) 2.5 μm thin film lines (Ti;Cu;Ni;Au) on ceramic (Al₂O₃) substrates; 3) 15 μm traces (Cu;Ni) on polyimide substrate for high density interconnection PCBs. The width of all types of traces was varying in the range of 100-500 μm. The set of temperature-current diagrams for different PCB scenarios are presented and analyzed. The temperature caused by Joule heating was measured using IR camera Flir A40 with macrolens. For different cases the current was set in the range of 0.1-3 A; the measured temperature was in the range of 20-140 °C. The close agreement between the results measured and simulated with ELCUT software tool was achieved.

Abstract: With the extensive use of infrared imaging reconnaissance equipment on the battlefield, recently how to simulate the reconnaissance effect of infrared imaging equipment has become a key issue that urgently needs to be solved in warfare simulation. To solve this problem, a method of reconnaissance effect simulation for infrared imaging equipment under warfare simulation is presented in this paper, which divides the entire reconnaissance process into a series of phases of the search, detection and recognition, confirmation and positioning. For the needs of a higher degree of confidence without too many complex calculations and parameter input, the established model is mainly dependent on the equipment tactical and technical performance indicators. Comparing the calculation results with the experimental data shows that the calculation error is smaller and this method presented has a good prospect in the warfare simulation.

Abstract: According to the characteristics of infrared imaging and rare bird species, a infrared imaging inspection method for rare bird species based on nonlinear filter algorithm has been proposed. Firstly, the CCD(charge-coupled device) sensors are used to obtain infrared video-data for rare birds, and then the captured images of rare birds are preprocessed to obtain the body axis length. Secondly, nonlinear filter algorithm, combined with physiological characteristics of rare bird species, is used to detect and identify the high-speed flying birds. Finally, the capabilities of EKF(extended Kalman filter) and PF(particle filter), the two kinds of nonlinear filter algorithm in inspecting have been researched deeply. Theoretical analysis and experiments demonstrate that the performance of PF is much better than EKF to inspect high-speed flying non-rigid object in complex environment.

Abstract: In this paper, we report our experimentation about measurement temperature of ignition cuts and chip phenomenon using infrared imaging methods, to model and simulate machine rotary cutting tool system. Finally this research was obtained of the optimum conditions expected of cutting magnesium at high speed and without coolant.

Abstract: On the basis of analyzing the process of passive thermal imaging in subdivision mid-wave infrared thoroughly, the paper makes clear the factors which influence imaging in subdivision bands of mid-wave infrared(SBMWIR). The forming models for images in SBMWIR are set up，and some simulation experiments on these models are done, from which the formation mechanism of the characteristic differences of imaging in SBMWIR are shown. There exist three differences in SBMWIR imaging, relating to the gray scale, environment effects on the target, and the contrast of target-background, which provide the foundation for extracting characteristics from images in SBMWIR, formulating fusion rules, and determining fusion weights.

Abstract: The paper investigates practical aspects of vibrothermographic testing of structures. Two application cases of vibrothermography are presented and discussed. The examples are weld test specimens and a military aircraft skin. Measurements have been performed with use of an in-house vibrothermographic testing system. In case of welded specimens a series of carbon steel test samples with different flaw types have been investigated. In case of aircraft testing, field measurements have been performed on a wing and fuselage sections in order to assess their structural integrity. The paper presents thermal image processing technique that allows to increase the quality and readability of the results coming from field measurements with poor ultrasonic excitation and with low thermal response from the structure. The paper is concluded with the discussion on applications of vibrothermographic testing in Structural Health Monitoring.