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Satellite-collected nighttime light provides a unique perspective on human activities, including urbanization, population growth, and epidemics. Yet, long-term and fine-grained nighttime light observations are lacking, leaving the analysis and applications of decades of light changes in urban facilities undeveloped. To fill this gap, we developed an innovative framework and used it to design a new super-resolution model that reconstructs low-resolution nighttime light data into high resolution. The validation of one billion data points shows that the correlation coefficient of our model at the global scale reaches 0.873, which is significantly higher than that of other existing models (maximum = 0.713). Our model also outperforms existing models at the national and urban scales. Furthermore, through an inspection of airports and roads, only our model's image details can reveal the historical development of these facilities. We provide the long-term and fine-grained nighttime light observations to promote research on human activities. The dataset is available at \url{https://doi.org/10.5281/zenodo.7859205}.

In the first part of this paper, we consider a partially overdetermined mixed boundary value problem in space forms and generalize the main result in \cite{GX} into the case of general domains with partial umbilical boundary in space forms. Precisely, we prove that a partially overdetermined problem in a domain with partial umbilical boundary admits a solution if and only if the rest part of the boundary is also part of an umbilical hypersurface. In the second part of this paper, we prove a Heintze-Karcher-Ros type inequality for embedded hypersurfaces with free boundary lying on a horosphere or an equidistant hypersurface in the hyperbolic space. As an application, we show Alexandrov type theorem for constant mean curvature hypersurfaces with free boundary in these settings., Comment: 22 pages,4 figures,final version,to appear in Adv.Calc.Var

In dialogue state tracking, dialogue history is a crucial material, and its utilization varies between different models. However, no matter how the dialogue history is used, each existing model uses its own consistent dialogue history during the entire state tracking process, regardless of which slot is updated. Apparently, it requires different dialogue history to update different slots in different turns. Therefore, using consistent dialogue contents may lead to insufficient or redundant information for different slots, which affects the overall performance. To address this problem, we devise DiCoS-DST to dynamically select the relevant dialogue contents corresponding to each slot for state updating. Specifically, it first retrieves turn-level utterances of dialogue history and evaluates their relevance to the slot from a combination of three perspectives: (1) its explicit connection to the slot name; (2) its relevance to the current turn dialogue; (3) Implicit Mention Oriented Reasoning. Then these perspectives are combined to yield a decision, and only the selected dialogue contents are fed into State Generator, which explicitly minimizes the distracting information passed to the downstream state prediction. Experimental results show that our approach achieves new state-of-the-art performance on MultiWOZ 2.1 and MultiWOZ 2.2, and achieves superior performance on multiple mainstream benchmark datasets (including Sim-M, Sim-R, and DSTC2)., Comment: Accepted by ACL 2022 main conference (long paper)

In this paper, we study a stability problem of free boundary hypersurfaces, and also capillary ones whose boundary supported on a horosphere in hyperbolic space. We prove that umbilical hypersurfaces are only stable immersed capillary hypersurfaces whose boundary supported on a horosphere. Using the same method, we show that a totally geodesic hyperplane is only stable immersed type-II hypersurface whose boundary supported on a horosphere., Comment: 16 pages,1 figure

In this paper, we consider a Minkowski inequality for a domain supported on any umbilical hypersurface with free boundary in space forms. We generalize the main result in \cite{Xia} into free boundary case and obtain a free boundary version of optimal weighted Minkowski inequality in space forms., Comment: 12 pages

Nowadays, wind turbine deicing has become a hot research topic. The traditional deicing method of blade has many problems, such as high energy consumption, low efficiency and low effect. In order to solve the above problems, the project team designed a wind turbine blade deicing device based on microwave and ultrasonic wave. During the operation, two deicing methods, namely microwave thermal energy, ultrasonic cavitation effect and thermal effect, were used to deice in stages to achieve the purpose of high efficiency and energy saving. The whole device is composed of walking system, microwave system and ultrasonic system, and the operation of the device is realized by the electrical control part. Compared with the existing deicing methods, the device can achieve the purpose of low energy consumption and high efficiency Deicing; in addition, the device has the advantages of flexible mechanism for control, less pressure on wind turbine blades, and low cost.

In recent years, a variety of fault diagnosis methods of multimode process have been developed. However, these multimode fault diagnosis methods need to assume that the data of batch production process is even-length, and there is no pollution in the data. To obtain better monitoring performance in a batch process with uneven-length data, a fault detection algorithm of multi-mode process based on local neighbor normalized matrix (LNNM) is proposed in this paper. The method highlights the contour features of various modes, accurately captures the nonlinear position relationship between modes and within modes. The local weighted algorithm (LWA) is first used to preprocess the uneven-length batch data. Then the main local neighbor normalized matrix is constructed for the training set of equal length. The K-means algorithm is used to mode clustering. In each mode, the local outlier factor (LOF) method is used to determine the first control limits for removing outliers. The MPCA model is established and the second control limits are determined for each mode. Furthermore, the matching coefficients of the control limits of each mode are calculated, and the unified statistics and control limits are determined. The fault detection of multimode process is carried out under the unified control limits. The algorithm is applied to the actual industrial semiconductor process. Simulation results show that the proposed algorithm improves the fault detection rate relative to the traditional fault detection algorithms. The effectiveness of the method is verified.

Existing aerospace metal parts or structural parts have the problems of finite elasticity, large mass, difficult manufacture of complex parts, expensive equipment, narrow range of shielding and electrostatic regulation. This study analyzed the tensile and bending properties of pure thermoplastic polyimide (TPI) 3D printing specimens printed by the nozzles with different diameters. The effects of different carbon nanotube (CNT) contents on the thermal and electrical properties of carbon nanotube composites were investigated. The relationship between the electrical conductivity, tensile properties, bending properties, resistivity and cyclic bending deformation of 3D printed specimens with different carbon nanotube contents was studied. Compared with the 0.4 mm nozzle, the tensile and bending strength of pure TPI specimen printed by a 0.8 mm nozzle were increased by 40% and 20%, respectively. In order to ensure the excellent mechanical and electrical properties of 3D printed composites, 3%wt carbon nanotubes-thermoplastic polyimide (CNTs-TPI) composites with appropriate tensile and bending strength were used to print the characteristic structure, and then the relationship between the deformation and conductive resistance was studied. By optimizing the 3D printing parameters and the filling contents of CNTs, it is possible to print complex parts which can be used in aerospace and industrial fields with special properties, such as electrical conductivity, mechanical properties, temperature resistance and anti-electromagnetic shielding.