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Solar diffuse radiation (DIFRA) is an important component of solar radiation, but current research into the estimation of DIFRA is relatively limited. This study, based on remote sensing data, topographic data, meteorological reanalysis materials, and measured data from radiation observation stations in Chongqing, combined key factors such as the solar elevation angle, water vapor, aerosols, and cloud cover. A high-precision DIFRA estimation model was developed using the random forest algorithm, and a distributed simulation of DIFRA in Chongqing was achieved. The model was validated using 8179 measured data points, demonstrating good predictive capability with a correlation coefficient (R2) of 0.72, a mean absolute error (MAE) of 35.99 W/m2, and a root mean square error (RMSE) of 50.46 W/m2. Further validation was conducted based on 14 radiation observation stations, with the model demonstrating high stability and applicability across different stations and weather conditions. In particular, the fit was optimal for the model under overcast conditions, with R2 = 0.70, MAE = 32.20 W/m2, and RMSE = 47.51 W/m2. The results indicate that the model can be effectively adapted to all weather calculations, providing a scientific basis for assessing and exploiting solar energy resources in complex terrains. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) is an essential parameter in environmental monitoring. However, due to the cloud contamination and the limitations of sensors, existing thermal infrared LST products are challenging to provide all-weather LST with high spatiotemporal resolution. Therefore, this paper presents a framework for reconstructing hourly LST under clouds based on the moderate resolution imaging spectroradiometer (MODIS) LST products. This framework consists of two main steps: (1) Instantaneous LST estimation for MODIS using a modified annual temperature cycle (ATCM) model and (2) Hourly LST reconstruction under all-weather conditions from atmospheric reanalysis data and MODIS instantaneous LST with the linear model (LM). The proposed framework is evaluated with the full year data of 2019 with tile number H26V05. The results show that the spatial distribution of the estimated LST is similar with the MODIS LST. Additionally, it could provide an accurate indication of the spatial and temporal variability of LST. Comparing the MODIS LST of the selected area for tile number H26V05 in 2019 with the estimated LST of the ATCM, the root mean squared errors (RMSEs) of the model are around 1K ~ 3K. The hourly LST is then reconstructed based on the LM method, and the RMSE is around 2K during the daytime and around 1K during the night-time. Finally, to verify the robustness of the hourly LST reconstruction method, the accuracy of the hourly LST was evaluated by the MODIS LST at different situations in the day. The results show that the missing data at one moment will cause the accuracy of the model decreasing by 0.09 ~ 1.67K at the corresponding moment. In general, the proposed framework has the potential to reconstruct the 1 km all-weather hourly LST with high accuracy and a certain level of robustness. [ABSTRACT FROM AUTHOR]

With the continuous improvement of urbanization levels in the Lhasa area, the urban heat island effect (UHI) has seriously affected the ecological environment of the region. However, the satellite-based thermal infrared land surface temperature (LST), commonly used for UHI research, is affected by cloudy weather, resulting in a lack of continuous spatial and temporal information. In this study, focusing on the Lhasa region, we combine simulated LST data obtained by the Weather Research and Forecasting (WRF) model with remote sensing-based LST data to reconstruct the all-weather LST for March, June, September, and December of 2020 at a resolution of 0.01° while using the Moderate-Resolution Imaging Spectroradiometer (MODIS) LST as a reference (in terms of accuracy). Subsequently, based on the reconstructed LST, an analysis of the UHI was conducted to obtain the spatiotemporal distribution of UHI in the Lhasa region under all-weather LST conditions. The results demonstrate that the reconstructed LST effectively captures the expected spatial distribution characteristics with high accuracy, with an average root mean square error of 2.20 K, an average mean absolute error of 1.51 K, and a correlation coefficient consistently higher than 0.9. Additionally, the heat island effect in the Lhasa region is primarily observed during the spring and winter seasons, with the heat island intensity remaining relatively stable in winter. The results of this study provide a new reference method for the reconstruction of all-weather LST, thereby improving the research accuracy of urban thermal environment from the perspective of foundational data. Additionally, it offers a theoretical basis for the governance of UHI in the Lhasa region. [ABSTRACT FROM AUTHOR]

Graphical abstract A single device with perovskite and polymer films can realize multifunctional energy applications in both solar cells and solid batteries. It shows a high PCE of solar cells and a large specific capacity of solid batteries with rapid charging ability. Moreover, the device can be directly photo-charged for energy storage. These results indicate it is a desirable device for wide applications. Highlights • A single polymer-perovskite based device acts as not only a solar cell but also an photochargeable ionic battery. • The device shows a considerable high efficiency as a solar cell, as well as it has large specific capacity and fast charge ability as a solid battery. • The operation principle of the device and the mechanisms of ionic movement are explained. Abstract Ionic movement in organometallic halide perovskite is generally looked as a very negative factor to perovskite based opto-electronic devices. It is considered one of the key inducements to efficiency and device stability. Here, we report that the ionic behaviors can lead to multifunctional energy utilizations by a single device with perovskite-polymer hybrid films. By manipulating and utilizing the ionic movement in the device, it acts as a solar cell and/or an ionic storage battery. Besides high efficiency for a solar cell, it has large specific capacities and fast charge ability of battery. It can be charged by light, which shows a promising device that directly transfers the light to electric energy for storage. This work paves a desirable way to achieve multifunctional devices for energy utilizations. It also indicates that ionic behaviors in perovskite have potential applications in various energy devices such as solar cells, ion battery and capacitors. [ABSTRACT FROM AUTHOR]

• An all-weather broadband high-gain antenna for maritime communication applications is developed from the perspective of hydrodynamics, hydrostatics, and electromagnetic performance. • A fixed aperture method is proposed to evaluate the gain bandwidth of the reflector independently from the radiating aperture of the antenna. • A W reflector is proposed for the three dipoles array and its equivalent antenna. The W reflector reaches a 150% 3-dB gain bandwidth theoretically, which is 53% and 90% larger than the gain bandwidth of the classic planar reflectors and the corner reflectors, respectively. • Two prototypes based on wideband high efficiency electromagnetic structure, with the use of a director and a W reflector, are devised. The two W reflectors are manufactured as continuous sheet and by rods, respectively. The proposed antennas realize 10-13dBi gains in a 45% bandwidth. • The proposed antenna is devised to be light weight, small wind loading, high mechanical strength, small size, low cost, lightning-strike resistant, and consistent coefficient of thermal expansion, without the need of any radome. The anti- deformation property of the proposed Antenna II is demonstrated to be 3.8 times higher than that of the classic Yagi antenna to be used in an open-ocean environment with a typhoon of force 12. An all-weather broadband high-gain antenna for maritime communication applications is developed in this paper. The proposed antenna, which is devised from the perspective of hydrodynamics, hydrostatics, and electromagnetic performance, is based on combining a wideband high-efficiency electromagnetic radiation structure (WHEMS) and a W reflector to achieve both superior mechanical and electrical performances. The proposed W reflector has a fractional 3-dB gain bandwidth of 150 % for a three-dipole array radiator, which is 53 % and 90 % larger than the gain bandwidth of the classic planar reflectors and the corner reflectors, respectively. To better adapt to the harsh marine environment and its potential IoT demands, the proposed antenna is devised to be light weight, small wind loading, high mechanical strength, small size, low cost, lightning-strike resistant, and consistent coefficient of thermal expansion, without the need of any radome. Two W reflector prototypes are ideated and manufactured from sheets and metal rods, denoted as Antenna I and Antenna II, respectively. Both the antennas realize 10–13 dBi gains in a 45 % bandwidth (1.7–2.7 GHz) with the sidelobe level lower than 12 dB, and a front-to-back ratio larger than 18 dB. The anti-deformation property of the proposed Antenna II is demonstrated to be 3.8 times higher than that of the classic Yagi antenna to be used in an open-ocean environment with a typhoon of force 1. [ABSTRACT FROM AUTHOR]