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Focusing on the imperative requirement for materials possessing both high solar reflectivity and low cost, by utilizing the finite difference time domain method, the relationship between the fiber diameters and the solar reflectivity of TiO2 nanofiber membranes was simulated. The results indicate that, at a TiO2 nanofiber diameter of 300 nm, the material demonstrates optimal broadband scattering capabilities, yielding an integrated scattering coefficient of 2.462 within the solar spectrum; the solar reflectivity demonstrates a direct correlation with the thickness of the fiber film, and the membrane material exhibits exceptional sunlight reflection performance while the thickness of the fiber film surpasses 150 μm. By manipulating the electrospinning process parameters and duration of spinning, TiO2 nanofiber membranes with varying fiber diameters and thicknesses were meticulously crafted. The solar reflectance test findings of the membrane material reveal that when the mean diameter of the fabricated TiO2 nanofibers is 293.2 nm and the thickness of the membrane is 155 μm, the membrane material exhibits a substantial solar reflectivity of 94.50%. [ABSTRACT FROM AUTHOR]

This paper investigated the variations in module temperature T and I-V,and analyzed the output law of photovoltaic modules in a day. Firstly, the temperature of the module during the day was found to be a result of coupling factors, not just related to the light intensity. The module output power was primarily determined by current, but not by voltage. Secondly, the series-parallel resistance of the modules basically decreased and then increased during the day. This was attributed to the increase in leakage current caused by high temperature and intense solar irradiance at noon. Compared with the series resistance, the parallel resistance was more affected by the environment during the day. Finally, the series and parallel resistances were relatively stable at high temperature conditions. The reason was that the nonlinear coupling factors that affect modules performance were more complex at low temperature condition. The above results were proved by comparing the theoretical and experimental series resistance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rapid development of UAV equipment provides a new remote sensing data acquisition platform. The acquisition of airborne hyperspectral image data generally includes three main steps: image acquisition, image preprocessing and image splicing. The acquired data is obtained by segment registration after wave first, and the data quality is crucial to the generation effect of subsequent orthophoto images. Most of the current studies are based on the direct interpretation of Orthophoto images, and it is impossible to avoid the distortion of Orthophoto images caused by the anomalies caused by the previous data acquisition or data preprocessing. The process of remote sensing data acquisition and transmission in natural environment is interfered by many factors, which results in some errors between the collected data and the actual situation. During data acquisition of hyperspectral imaging system of UAV, image distortion, such as white noise and stripe noise, will be caused due to route change and solar irradiance change, which seriously interferes with the acquisition of aerial images. How to establish effective evaluation indicators to guide the quality interpretation of aerial images is a matter of concern. In order to solve this problem, this study uses the ground object spectrometer (350-2 500 nm) and airborne imaging spectrometer (502.56-903.2 nm) to obtain the canopy spectrum of cotton crops in the study area .The aerial image size is 42 bands× 768 pixel×768 pixel. Combined with the central wavelength of the imaging spectrometer, the spectral data of the ground object spectrometer with the same half wave width are separated for spectral information comparison. Analyze the spectral characteristic positions and amplitudes of typical vegetation, such as green peak, red edge and red valley, to verify the quality of spectral information and ensure the accuracy of spectral information acquisition of reference images. Referring to previous research contents and actual data acquisition results, the main distortion types are locked, and the collected high-quality reference images are sequentially generated into five types samples of different degrees, including white noise, defocus blur, motion blur, spectral smoothing and stripe noise, through digital image processing technology. Each type includes 150 samples and a total of 750 samples, Based on the statistical results of the actual noise samples, a total of 50 noise sample sets (stripe noise and mixed white noise) and reference images were constructed by using morphology and interpolation processing. According to the characteristics of hyperspectral images, 3 categories of 15 indexes for calculating the spatial information, spectral information and spatial spectral composite quality of images covering the band are established. With the help of multiple types of samples with different degrees of distortion, the effectiveness of the indexes is evaluated by using the correlation analysis method. The correlation analysis of the indexes is carried out in combination with the two categories of samples. The results show that the each image quality calculation index proposed in this paper was significantly correlated with the deterioration of image quality (P<0.01). The correlation of all indicators for real noise samples has decreased to varying degrees. Only four indicators, mean absolute error MAE (0.609, P<0.01), mean square error MSE (0.459, P<0.01), relative root mean square error RRMSE (0.502, P<0.01) and overall information fidelity F (-0.471, P<0.01) meet the correlation analysis. The research results can provide reference for the quality evaluation of low altitude airborne hyperspectral image data and the quality analysis and distortion index selection in the image processing process. [ABSTRACT FROM AUTHOR]

Solar radio spectrum images play an important role in the observation, research and prediction of solar activity and space weather. The solar radio broadband dynamic spectrometer is the main equipment for observing solar radio signals in China. However, it is affected by the window time, observation equipment and the law of solar activities, and the collected spectrum data has the problem of few effective samples. In view of this situation, a few-shot learning method based on meta-learning and transfer-learning is proposed to improve the classification performance of solar radio spectrum images. First, the model learns meta-knowledge on the meta-learning benchmark dataset, then defines the model for a few sample recognition of radio spectrum images, and finally transfers the meta-knowledge to the classification task of the spectrum image dataset. Through experimental analysis and performance comparison of multiple meta-learning methods, it proves that the method in this paper is advanced and effective. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Imaging Science & Photochemistry is the property of Imaging Science & Photochemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large-scale full solar spectrum irradiation system is an important part of the solar simulator. Irradiation non-uniformity is one of the key technical indexes for the large-scale solar simulator. Some technical problems about difficultly meeting the national standard and the poor optical spectra matching property of light sources exist in traditional solar simulators. Regarding the present issues of the large-scale solar simulators, a full-spectrum irradiation system was designed, and the irradiation uniformity of the system was simulated by using the software Zemax. An innovative concept, irradiance decay pattern, is put forward, and the irradiation uniformity is optimized in this way. A plasma light source produced by Solaronix, Switzerland is used, and the spectrum of full-spectrum solar irradiation system can reach Level A of IEC standard. The irradiance of the proposed system was tested by using a spectral radiometer in the full-spectrum scope. The test results show, when the irradiance is 280 W/m2, the irradiance nonuniformity is 5. 7% if the irradiance decay pattern is switched on, or 8. 4% if the pattern is off. Referring to the national standard GB/T12637—90 General specification for solar simulator, in the effective radiation area of 2 400 mm × 6 000 mm, the irradiance uniformity is better than Level C, and almost reaches Level B. [ABSTRACT FROM AUTHOR]