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In the process of remote sensing image restoration, color correction is very important. The polynomial algorithmcolor correction method based on standard color card is the most commonly used method. However, the traditional polynomial fitting method needs to determine the most appropriate combination of polynomials, and only one polynomial function fitting method is used. So it is difficult to guarantee high accuracy and good generalization performance at the same time. In order to solve the above problems effectively, this paper proposes an automatic piecewise polynomial fitting method. This study established the mapping between collected RGB value and standard RGB value through the calibration of the X-rite Color Checker, and represented the color difference by computing $\Delta E$ in CIELab color space. This improved algorithm adopts the idea of segmentation to select the most suitable function in different intervals, and the interval of segmentation is automatically determined by the chromatic aberration standard. The experimental results show that this algorithm has high correction accuracy and this algorithm is more adaptable to photos under different lighting conditions.

In order to achieve continuous fine recognition of targets with limited distance, a large zoom ratio near infrared continuous zoom optical system has been designed. Based on the zoom system and its automatic design principle of aberrations, reasonable technical indicators were formulated, the initial structure of the system was determined, and the optical design software CodeV was used to optimize it to achieve a continuous zoom optical system with good imaging quality. The system uses a detector of 4.5-micron $\times$ 4.5-micron pixels, and the field of view is 2.7-degree $\times$ 2.7-degree $\sim$ 12.7-degree $\times$ 12.7-degree, F number is 4.8, using mechanical positive group compensation method, composed of front group, zoom group, compensation group and rear group, including 14 spherical lenses. The design results were evaluated for image quality and the cam curve was solved. The design and analysis results show that the system achieves a continuous zoom of 70-mm~350-mm in the 750-nano $\sim$ 900-nano band. The optical modulation transfer function of the system is better than 0.3 at Ill-lp/mm, the maximum distortion is less than 2%, the image quality is good, and the processing cost is low. The system has the characteristics of large zoom ratio, high resolution, compact structure and smooth zoom curve, and can be used for fine recognition of limited distance targets.

Musculoskeletal pain (MSP) is one of the most severe complaints in women undergoing menopause. The prevalence of MSP varied when taking the menopausal state and age factor into consideration. This study investigated the prevalence of MSP in perimenopausal women and its association with menopausal state. The MEDLINE, Embase, Web of Science, and PubMed databases were searched from inception to July 2020, and 16 studies were retrieved for the current meta-analysis. The primary outcome measure was the MSP Odds Ratio (OR). The estimated overall prevalence of MSP among perimenopausal women was 71% (4144 out of 5836, 95% confidence interval (CI): 64%-78%). Perimenopausal women demonstrated a higher risk for MSP than premenopausal ones (OR: 1.63, 95% CI: 1.35-1.96, P=0.008, I2=59.7%), but similar to that in postmenopausal ones (OR: 1.07, 95% CI: 0.95–1.20, P=0.316, I2=13.4%). The postmenopausal women were at a higher risk of moderate/severe MSP than the premenopausal ones (OR: 1.45, 95% CI: 1.21-1.75, P=0.302, I2=16.5%) or the perimenopausal ones (OR: 1.40, 95% CI: 1.09–1.79, P=0.106, I2=55.4%). In conclusion, the perimenopause is a state during which women are particularly predisposed to develop MSP. As to moderate to severe degrees of MSP, the odds increase linearly with age, from premenopause to peri- and then to postmenopause.

With the development of space optical technology,space camera is required to be characterized by both high resolution of ground sample distance and ability of multi-spectral imaging.Thus the optical system design must be satisfied with the demand of large field of view and small distortion.Based on the on-axis three-mirror-anastigmat system,a new type of optical system was designed,which is characterized by small central obscuration,low optical distortion and reasonable arrangement of panchromatic and multi-spectral CCD.The results indicate that the field angel reaches 1.6°,the system line central obscure coefficient is lower 1/3,the optical system distortion is less than 0.5%,MTF is superior to 0.47 at 50 lp/mm,the image quality reaches the limit of optical diffraction,when the focal length is 12 000 mm,focal ratio is 12,and the spectrum band is from 450 to 900 nm.So the proposed optical system can meet the demand of high resolution multi-spectral space cameras.

Based on the principle of null lens,a new method of error-separation was proposed in null testing.A mathematic model was developed to separate misalignment-induced aberration from the test result.The method was used in the simulations of an off-axis aspheric mirror.The wavefront aberration induced by misalignment is 0.0026λRMS(λ=632.8 nm) after the alignment,compared with 0.2332λRMS before the alignment,which reflects that this method has high accuracy and can improve the efficiency of the null test.

With the development of space technology,small satellite will be widely applied.The paper design a catadioptric system base on Ritchey-Chretion system which including three sphere correction lens.The system has a focal length of 1000,F number of 5,and spectrum band of 450~900 nm,and the field angle reaches 2.3°.the result indicates that,MTF reaches 0.47 at 77 lp/mm with 15% central obscure,the quality of image approaches the diffraction limit,and optical system distortion is less than 0.5%.The system with simpler structure,small size and light weight,can be used in light-small satellite.

In order to improve the imaging quality of optical system, high precision surface of mirrors are put forward to improve their imaging quality. It makes their fabrication harder. Wavefront aberration induced by alignment is analyzed in off-axis parabolic mirror system based on the wavefront aberration theory. The surface error of off-axis parabolic mirror can be compensated by alignment so it will reduce the fabrication difficulty, shorten its period and save its cost. In the simulations of an off-axis parabolic mirror with surface error λ/40 RMS (λ=632.8 nm) ( Root Mean Squre) with ZEMAX software, the figure accuracy is under λ/40 RMS after alignment. It shows that surface error of off-axis parabolic mirrors could be compensated effectively by alignment.

Oxide thin film transistor with an oxide channel layer is investigated to cater to the requirements of transparent electronics for the high mobility, good uniformity, and large band gap. Owing to its special conduction mechanism, high carrier mobility can be realized even in the amorphous phase. Oxide-based thin films have been prepared by using a number of methods, such as pulsed laser deposition, chemical vapor deposition, radio-frequency sputtering and solution-derived process. Solution processing is commonly used in TFT applications because of its simplicity and potential application in printed device fabrication. In the solution process, the conductivity of multicomponent oxide films can be controlled by incorporating charge-controlling cations. In this paper, bottom-gat topcontact thin film transistors are fabricated by using solution processed InGaZnO channel layers. The effects of annealing temperature and Ga content on the properties of thin film transistor are examined. Optical transmittance of InGaZnO thin film is greater than 80% in the visible region. Electrical characteristics of InGaZnO thin film transistor are improved by increasing annealing temperature. The threshold voltage of solution-processed InGaZnO transistor decreases from 6.74 to -0.62 V with annealing temperature increasing from 250 to 400 ℃, owing to the increase in electron concentration in the active layer. A lower annealing temperature suppresses the generation of carriers outside of the control of Ga cations. X-ray photoelectron spectrum measurement shows that the electron concentration increases because oxygen vacancies generate electrons. The incorporation of Ga into a InZnO compound system results in reducing the carrier concentration of the film and an off-current of thin film transistor. As the Ga ratio is increased at an identical In and Zn content, the carrier concentration of the film decreases and the threshold voltage of thin film transistor shifts towards the positive direction. As the content of Ga is increased in the oxide active layer of transistor, the subthreshold amplitude decreases, and the on/off ratio is improved. This is a consequence of the Ga ions forming strong chemical bonds with oxygen as compared with the Zn and In ions, acting as a carrier suppressor. The performances of thin film transistor with an atomic ratio of In: Ga: Zn=5:1.3:2 are optimized as follows: saturation mobility of 0.43 cm2/(Vs), threshold voltage of -1.22 V, on/off current ratio of 4.7104, subthreshold amplitude of 0.78 V/decade.