Abstract:Polarization imaging plays a very important role in the applications such as atmospheric detection, environmental monitoring, resource investigation and military reconnaissance. It has been used in aerial and space remote sensing. The development of near-space vehicles provides a new platform for polarization imaging remote sensing and shows its remarkable dominance. The polarization principle and polarization detection and imaging are presented. The design scheme of a staring high resolution polarization imaging system for near-space vehicles is given and its feasibility is verified after its performance is analyzed.

Abstract:The crosstalk in a multi-element photoconductor is one of the factors which have influences on the performance of a system. The electronic crosstalk caused by ground resistance can be reduced by increasing bias resistance. According to the characteristics of a HgCdTe photoconductive detector, a preamplifier with a constant current bias circuit is designed. The operation principle and noise of the circuit are analyzed. The noise model of the circuit is given. An expression for its equivalent input noise is derived. Finally, the circuit is implemented and its noise performance is tested.

Abstract:The typhoon center is usually located manually by meteorologists. This location method has a low degree of automation. According to the movement characteristics of typhoon and the meteorological analysis theory, a single infrared satellite cloud image is used to establish a method for extracting the dominant cloud movement vectors. On this basis, the optimal target function for locating the typhoon center automatically is set and resolved. The automatical location of the typhoon with an eye or without an eye is realized. The method is used to simulate the automatical location of the center of typhoon ``HAITANG' in several cloud images obtained in 2005. The result shows that this method has a high location accuracy and can be used as a good technical means for the automatical location of typhoon center.

Abstract:The polarized reflection light from a target is accompanied by its bi-directional reflection light. To determine the quantitative relation between the polarized reflectance and the bi-directional reflectance on the surface of anthracite, the polarized reflectance on the surface of anthracite is measured at multi-angles and the polarized reflectance and bi-directional reflectance are analyzed according to the degree of polarization. The result shows that the influence of an incident angle on the degree of polarization is determined by the surface roughness and carbon content of anthracite. With the increase of the incident angle, the degree of polarization can be increased in the range of 0°～60°. With the increase of carbon content, the degree of polarization can be increased too. The degree of polarization of the anthracite with a smooth surface is greater than that of the anthracite with a rough surface. The degree of polarization can indicate the proportional relation between the specular reflection component and the diffuse-reflection component in the reflected light. The calculated degree of polarization can show the inherent nature of anthracite and quantify the relation between the polarized reflectance and the bi-directional reflectance more minutely.

Abstract:ZnO thin films with different thickness were prepared on glass substrates by using a sol-gel method. The effect of different sol ratio and concentration on the thermal radiation properties of the ZnO thin films was analyzed. The ZnO thin film had the best thermal radiation property and best absorption ability when its sol ratio was 1∶1 and its concentration is 0.8%. The structure and morphology of the ZnO thin film were characterized by using both X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) technologies. The results showed that the prepared ZnO thin film exhibited its hexagonal wurtzite structure with preferred orientation at (002) and had good crystallization behavior.

Abstract:Frequency selective surfaces were analyzed by using a finite element method and the feasibility of simulating frequency selective surfaces by an Ansoft HFSS software was studied. By taking the frequency selective surfaces of a hexagon cell for example, the simulation method and process of the frequency selective surfaces were explored. A hexagon cell sample with frequency selective surfaces was fabricated by using a photolithography technology. The simulation curves were compared with the measured curves of the sample. The result showed that simulating the frequency selective surfaces by using the Ansoft HFSS was feasible. At the same time, the reliability of the simulation was further verified in the cirle and cross cell structure examples. In this simulation, both time domain characteristics and frequency domain characteristics of the frequency selective surfaces were considered. In contrast, either time domain characteristics or frequency domain characteristics could be considered in the traditional method. So, this simultaion method was more accurate.

Abstract:According to the theory of heat radiation and the temperature measurement principle of an infrared thermal imager, a platform for testing clothing comfort based on the infrared thermal imaging technology is built. The surface temperature field distribution of the clothing worn by a person is directly measured by using an infrared thermal imager in different environment. The collected thermal images are used to analyze the temperature field and judge the change of the actual temperature of the clothing worn by the person, so as to deduce the thermal insulation properties of the clothing and the cloth used. The objective experiment result and the subjective assessment result are analyzed. The analysis result shows that among three experimental clothing, the clothing made of the cloth containing 50% soybean fiber and 50% cotton has the best thermal-wet comfort. This evaluation method based on the infrared thermal imaging technology is effective and can be used as one of the important tools for judging the thermal comfort of clothing.

Abstract:An infrared thermal imager has its incomparable dominance in the monitoring of external malfunction of electric power equipment. Since it can detect the actual temperature distribution of the electric power equipment in operation contactlessly and accurately, it has become an effective detection means used commonly by the electric power sector. When the obtained infrared thermal images are processed by using the image enhancement and edge detection methods in the MATLAB image box, the accurate fault location in the electric power equipment can be determined.

Abstract:According to the finite difference principle, a one-dimensional Schr\"{o}dinger equation can be converted into a set of nodal linear equations expressed in a matrix equation after the space is divided into a series of discrete nodes with an equal interval. The matrix left division command offered in the MATLAB software can be used to derive the function approximation of each unknown nodal function. This method is simple in concept, convenient in operation and can solve large linear equations without more efforts in programming.