In order to meet the design requirements of multi-band, long focal length, large aperture and compact structure, the reflective optical system is studied. Based on the imaging theory of the coaxial three-mirror system, in order to avoid the existence of blocking in the optical system and improve the imaging quality, the design uses Zemax optical software to introduce a method to optimize off-axis three-reflection optical system. Compared with the control optimization based on ZPL language, the method is more convenient and intuitive. It does not need to use complex aspheric surface and only uses the conic coefficient of curved surface to meet the design requirements, which greatly reduces the cost and difficulty of processing and testing. Using the off-axis field-of-view, a visible and mid-wave infrared dual-band off-axis three-reflection optical system with a focal length of 1000 mm, the diameter of 6 in and a field-of-view of 2.2°×0.22° is designed. The simulation results show that MTF of the full field-of-view is greater than 0.4 at the spatial frequency of 17 lp/mm in the 3--5 m band, and MTF of the full field-of-view is greater than 0.7 at the spatial frequency of 50 lp/mm in the 0.4--0.7 μm band. The imaging quality of the system is good, close to the diffraction limit.

Infrared radiation characteristic data is widely used in target infrared characteristic recognition and stealth characteristic evaluation in outfield, and it plays an irreplaceable role in the security and military fields. The acquisition of target infrared radiation characteristic data needs to be based on the system′s radiation calibration. For medium-and long-wave measurement systems, infrared radiation calibration is mainly for fixed-focus systems, but the radiation calibration for zoom systems is less. The model of the infrared radiation calibration was established for the continuous zoom system, and the short-wave continuous zoom system with 1000 mm aperture was analyzed. Data analysis results show that as the F number increases, the radiation response gain of the system decreases. The analysis of its influence on radiation measurement has certain engineering significance.

Silicone rubber adhesive has good low temperature resistance, so it is often used in the bonding process of composite substrate of cooled infrared detector. The effect of the primer on the bonding strength of silicone rubber was studied. The tensile results show that the average bonding strength of the sample directly bonded was 4.07 MPa at liquid-nitrogen temperature, while the average bonding strength of the sample pretreated with the primer reached 6.34 MPa. In addition, by observing the fracture surface of tensile sample, it is found that more silicon rubber remained on the fracture surface of the sample pretreated with the primer. Therefore, pretreatment with the primer can effectively improve the bonding strength of silicone rubber, which is helpful to improve the reliability of infrared detectors.

In order to explore the influence of relevant parameters on the cooling performance of space-borne pulse tube cryocooler and improve the consistency of cooling performance, a random forest regression model based on machine learning is established to make regression prediction of the cooling performance and various independent variables. The average relative error of cooling performance prediction is 5.62%, and the average certainty coefficient is 0.805. In terms of the influence degree of the variables, the first and second feature are mesh filling rate and magnetic induction intensity, which are consistent with the actual experimental results(the actual input power changes of mesh filling rate and magnetic induction intensity are 6.11 Wac and 3.52 Wac, which are much larger than the other four independent variables). The results show that RFR has the high accuracy and robustness, which provides a new idea for the consistency improvement of the cooling performance of space-borne pulse tube cryocooler.

Dragonflies are considered to be one of the insects with simple flying behavior and efficient mobility, so they have become the bionic design prototypes of many micro air vehicles (MAV). The excellent flight characteristics of dragonflies are inseparable from their wing characteristics. It can not only withstand a variety of loads during flight, but also maintain high-efficiency flight characteristics. The research status and latest research progress of dragonfly wing structure characteristics, flight characteristics and dragonfly flapping-wing MAV are summarized. The wing vein, wing membrane, wing knot, pterostigma, fold structure, body fluid flow, material characteristics, flight mechanism and infrared detection application of dragonfly wings are summarized. In addition, according to the miniaturization requirements of the bionic flapping-wing MAV, the future research directions are analyzed.

The clinical efficacy of Huangqi Jianzhong Decoction in the treatment of chronic non-atrophic gastritis (CNAG) is observed, and the feasibility of using infrared thermal imaging technology to evaluate the clinical efficacy of CNAG is discussed. 76 CNAG patients with deficiency-cold type of spleen and stomach are divided into control group (treated with western medicine) and treatment group (treated with Huangqi Jianzhong decoction), and the changes of symptom scores and infrared temperatures of the observation sites are observed before and after treatment in the two groups. The results show that the total effective rate of the treatment group is 94.4%, while the total effective rate of the control group is 77.8%（P<0.05）.The infrared temperatures of observation sites in 2 groups are higher than that before the treatment (P<0.05), and the infrared temperature increasement of observation site in treatment group is larger than that in control group（P<0.05）.Therefore, Huangqi Jianzhong decoction has a good therapeutic effect on CNAG, which is worthy of study and promotion. Infrared thermal imaging technology can reflect the change of curative effect in time, objectively and conveniently and can compare the curative effect, which provides objective and visual basis for dialectical treatment of traditional Chinese medicine.