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The occurrence of forest fires can impact vegetation in the ecosystem, property, and human health, but also indirectly affect the climate. JULES-INFERNO is a global land surface model, which simulates vegetation, soils, and fire occurrence driven by environmental factors. However, this model incurs substantial computational costs due to the high data dimensionality and the complexity of differential equations. Deep learning-based digital twins have an advantage in handling large amounts of data. They can reduce the computational cost of subsequent predictive models by extracting data features through Reduced Order Modelling (ROM) and then compressing the data to a low-dimensional latent space. This study proposes a JULES-INFERNO-based digital twin fire model using ROM techniques and deep learning prediction networks to improve the efficiency of global wildfire predictions. The iterative prediction implemented in the proposed model can use current-year data to predict fires in subsequent years. To avoid the accumulation of errors from the iterative prediction, Latent data Assimilation (LA) is applied to the prediction process. LA manages to efficiently adjust the prediction results to ensure the stability and sustainability of the prediction. Numerical results show that the proposed model can effectively encode the original data and achieve accurate surrogate predictions. Furthermore, the application of LA can also effectively adjust the bias of the prediction results. The proposed digital twin also runs 500 times faster for online predictions than the original JULES-INFERNO model without requiring High-Performance Computing (HPC) clusters. The implementation code of this study and the developed models are available at https://github.com/DL-WG/Digital-twin-LA-global-wildfire. [ABSTRACT FROM AUTHOR]

Elastic deformation and gaseous rarefaction effects are of great importance to the static and dynamic characteristics of gas microbearings. Based on the effective viscosity model of Veijola, the flexibility matrix was established by finite element method to calculate the elastic deformation of bearing shell surface, and the modified Reynolds equation considering the influence of effective viscosity and elastic deformation was deduced. The effects of bearing elastic modulus, gas effective viscosity, bearing structural parameters and disturbance frequency on the static and dynamic characteristics were analyzed by solving the modified Reynolds equation, effective viscosity equation and elasticity equations of ultra-thin gas film lubrication. The results indicate that the gaseous rarefaction effect significantly reduces the load carrying capacity of microbearings. The load carrying capacity of microbearing increases with the increase of eccentricity ratio and bearing number. Increasing the flexibility of bearing shell can improve the load carrying capacity and friction coefficient of microbearings, while the bearing capacity and friction coefficient of elastic microbearings considering the effective viscosity of gas are small. Compared with the rigid bearing, the reduction of the elastic modulus of the bearing shell significantly increases the dynamic stiffness coefficient and reduces the direct damping coefficient of the microbearings, while considering the gas effective viscosity effect caused by the rarefaction effect reduces the direct stiffness and increases the direct damping coefficient of the microbearings [ABSTRACT FROM AUTHOR]

The building sector is one of the highest energy consuming sectors in the world as well as in China, it is urgent to seek an energy efficiency way of sustainable architecture development. From the perspective of tradition, this paper focus on strategies of energy efficiency design that contained in excellent vernacular dwellings. On the basis of analyzing an example of Kangbaiwan Mansion, it illustrates the advantage of environment ecosystem, and summarizes the physical and cultural characteristic of its buildings, especially the climate-adapting overall arrangement and sustainable strategies of natural ventilation and passive solar gain, which can be a fertile source of modern energy efficiency architecture design as well as a proper way of inheriting the outstanding traditional culture.

Cu2V2O7 is an important material to improve low conductivity of Li4Ti5O12. Herein, Li4Ti5O12/Cu2V2O7 with different Cu2V2O7 ratios is successfully prepared by a liquid phase‐assisted dispersion method. The results show that the electrochemical properties of Li4Ti5O12 are affected by the Cu2V2O7 content incorporated in the composites. Among all obtained samples, Li4Ti5O12/0.05 Cu2V2O7 reveals the best electrochemical performance and capacity retention rate, and its first cycle specific capacity is 246.3/197.2 mAh g−1 when the current density is 30 mA g−1 and it maintains values of 175.8/175 mAh g−1 for 200 cycles between 1.0 and 3.0 V. The resulting Li4Ti5O12/0.05 Cu2V2O7 composite also displays higher capacities at elevated current densities of 120 and 1200 mA g−1, with values always superior to those of the original Li4Ti5O12. The detailed electrode dynamics analysis illustrates that the introduced Cu2V2O7 phase in the composites improves the cycle stability and lithium‐ion transfer rate of Li4Ti5O12. Through in situ X‐ray diffractometry (XRD) test analysis of the Li4Ti5O12/0.05 Cu2V2O7 composite material, it is confirmed that the lithium storage mechanism is improved, where metallic Cu is formed in situ during each charge and discharge reaction process; thereby, the electronic conductivity of the composite material is improved and charge transfer resistance of the bulk material is reduced. [ABSTRACT FROM AUTHOR]

The application of bamboo fibers (BFs) to reinforce the impact strength of polylactic acid (PLA) is attractive because of its low cost and high specific strength. However, the main disadvantages of PLA/BF composites are their low compatibility and poor interfacial adhesion caused by different surface energies. In this work, a bio‐based compatibilizer is used to modify PLA/BF composites with a BF content up to 30 wt%. First, sebacic acid (SA) and epoxidized soybean oil (ESO) are reacted to obtain ESO‐SA oligomers with different branching and crosslinking structures. Next, ESO‐SA is incorporated into a PLA/BF composite through dynamic vulcanization, and fully bio‐based PLA/BF/ESO‐SA ternary composites are prepared. Compared to the PLA/BF composite without ESO‐SA addition, the impact strength of PLA/BF/16ESO‐SA12 increases from 5.8 to 14.55 KJ/m2. The toughening mechanism results confirm that the chemical structure of ESO‐SA is the key indicator of the toughening efficiency. [ABSTRACT FROM AUTHOR]