Abstract:Human action recognition is one of the hotspots in the field of computer vision and pattern recognition. As an important branch of human action recognition, abnormal human action detection has arrested attention of academic and business communities constantly. The research on human action recognition has developed from the research based on human shape features to the research based on gradient design. At present, with the new development of neural network, deep learning has been widely used in action recognition. Because infrared wavebands have advantages of dealing with weak light environment and 24-hour monitoring, they have been applied to the research on human action recognition. This will become a new research hotspot in the field of human action recognition.

Abstract:In recent years, infrared imaging technology has developed rapidly in China. According to the operating temperature, Infrared Focal Plane Arrays (IRFPAs) can be divided into cooled ones and uncooled ones. IRFPAs have the advantages of high sensitivity, high accuracy and excellent performance, but they are expensive. So they are mainly used in the military field now. In the use of a certain cooled infrared thermal imager, if the temperature of the scene changes greatly or if the imager operates at an extreme ambient temperature, a phenomenon may occur, that is, the image may exhibit white in the middle and exhibit black in the corner or vice versa when integration time is adjusted. Firstly, infrared image data are collected at different blackbody temperatures in different integration time. Let the phenomenon be recurrent according to the above problem. Then, the root of the problem is analyzed and the solution is put forward according to the principle of two-point correction. Finally, the correctness of the method is verified by the experimental data and the solutions to the problem are summarized.

Abstract:Cadmium Zinc Telluride (CZT) is a II-VI compound semiconductor material with excellent performance. Its energy gap can be tuned continuously with different zinc content. So it is an excellent substrate material for the HgCdTe material to be used to manufacture infrared detectors. Several lapping and polishing methods of cadmium zinc telluride including hand lapping, mechanical polishing, chemical polishing, mechanochemical polishing are presented. With the aid of various characterization techniques and reformed methods, significant progresses have been made in the surface processing of CZT.

Abstract:The principle of Secondary Ion Mass Spectrometry (SIMS) and its importance in the manufacture of infrared semiconductor materials and Infrared Focal Plane Array (IRFPA) devices are presented. Through SIMS tests of As:doped HgCdTe and CdTe/InSb materials, the influences of different ion sources and primary beam intensity on test results are studied. The study lays a foundation for the further study of application of SIMS in infrared detector materials.

Abstract:To solve the problems of low contrast between a local target and its background and segmentation of an infrared handprint image with blurred edge, an edge blurred infrared target extraction algorithm based on geometric growth with structural morphology is proposed. Firstly, the maximum entropy method and threshold extension are used to segment the image roughly. Secondly, the feature points of the regional blocks in the roughly segmented target area are extracted to construct the structural morphology of the hand. Finally, by using the regional block feature point to find the seed point and using the distance relationship between the seed points and the corresponding feature points as the growth decision condition for geometric growth, the target area is obtained from the image. The method is compared with the conventional extraction algorithm experimentally. The results show that the proposed method can extract the complete target more effectively for the blurred infrared images with blurred edge.

Abstract:In the atmospheric sounding over ocean, because of the relatively low reflectivity of ocean, it is feasible to improve the incident radiation energy by observing the solar glint and hence to get the visible and short wave infrared atmospheric data with high signal-to-noise ratio. Essentially, solar glint is an image of the sun. Its divergence angle relative to the satellite is rather small. Therefore, it is necessary for the satellite to use a 2-axis tracking mechanism to implement solar glint observation. A 2-dimension solar glint tracking calculation algorithm considering the ellipticity of the earth is studied. The influence of the ellipticity of the earth and the sun on the calculation error is analyzed. The iterated convergence performance of the algorithm within a year is given and the results are compared with those output by the Satellite Tool Kit (STK).

Abstract:To investigate whether β-carotene has a phase change under high pressure, high pressure Raman spectroscopy of β-carotene in the range of 0 to 30 Gpa pressure was performed. By evaluating the linear function change of Raman spectral frequency-pressure in different pressure ranges, whether or not a phase transition occurs can be determined. The study shows that when the pressure rises to about 7 Gpa and 14 Gpa, the frequency-pressure linear function equation of β-carotene molecules changes, which means that the phase transition occurs. To analyze whether the frequency-pressure linear relationship is changed is a simple and convenient technical method for judging whether the phase shift is changed. The study of stress phase transition of neat β-carotene has not been reported.

Abstract:The applications of infrared thermal imaging (IRTI) in disease prevention are summarized. The coherence point between IRTI and Tradition Chinese Medicine (TCM) is found. By browsing the latest literatures at home and abroad, the applications of IRTI in disease prevention are understood. The result shows that IRTI has a high coherence point with the theory of TCM in holism concept and eight-principle syndrome differentiation. IRTI has exhibited a strong advantage in combination with the disease prevention of TCM and has better complementarity with TCM. This technology has been widely used for physical identification, health management of chronic diseases, TCM syndrome differentiation and evaluation of treating efficacy in the `Disease Prevention'' project. It is helpful to the disease intervention of those who have chronic disease and subhealth etc so as to achieve the goal of targeted therapy. Although the `Disease Prevention'' project has made some progresses, some shortcomings still exist. For instance, the current physical identity lacks certain objectivity, the whole process takes a long time and the physique classification is unreasonable etc. IRTI is more objective and scientific in physical identification. So, it has a broad application prospect in the `Disease Prevention'' project.