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Aiming at the problem of degradation of correlation quality caused by excessive idealization of noise in the traditional track correlation model, this paper introduces the uncertainty theory in the track correlation process, and uses the uncertainty normal distribution in the theory to describe the noise in the track correlation, thus proposing a new track correlation model based on the uncertainty distribution. The motion equation and observation equation are reconstructed under three motion states uniform velocity, uniform acceleration, and variable acceleration. At the same time, this paper also uses a variety of traditional noises (including Gaussian noise) to simulate various complex noise environments, and uses a variety of algorithms to solve the model in this paper and the traditional model, and finally compares the performance of the two models under the same conditions, thus verifying the superiority and applicability of the uncertain normal correlation model from a variety of angles to the greatest extent.

In order to detect the all-range and large degree threats coming from the area of responsibility rigorously, the method of covering the blind zone with multi-airborne early warning (AEW) cooperation is studied based on the absolute Doppler. Firstly, the cause and changing rules of the target radial velocity are analyzed, the mathematical expression of the absolute Doppler is deduced, which can adapt the thesis factor relating with the Doppler blind zone to the distance between the absolute speed of the target and the location of AEW and target. Secondly, the modeling and simulation method is employed, and the Doppler blind zone map that is characterized with the number of times of detection is designed based on the expression of the flutter concave, a method of plotting the positional relationship on the map for multi-AEW at the principle which can guarantee the radial velocity blind area not falling or as little as possible falling on the important orientation area, and the collaborated deployment in completed. The simulation verified the practicality and effectiveness of the method through the cooperation examination of the two-AEWs employing the weird formation. [ABSTRACT FROM AUTHOR]

The application of matrix information geometry to radar signal processing and target detection is a new and interesting subject. Wake vortices are Doppler-spread after Fourier transform. The traditional Moving Target Detection (MTD) method cannot adequately accumulate returns power of the whole spectrum. Based on matrix information geometry, a matrix Constant False Alarm Rate (CFAR) detection method is proposed to improve the detection performance of a weak wake target. In this method, covariance matrices of the observed data can be constructed into a matrix manifold; compared with CFAR detection, the geodesic distance between the covariance matrix in the detection cell and the mean of covariance matrices in the secondary cell is regarded as the detection statistics. Using simulated wake vortices, the return data in background noise and the iterative estimation performance of Riemannian mean are analyzed; the geodesic distance of covariance matrices of target return and noise with varying signal-noise rate is analyzed; and the detection performance of the matrix CFAR and the conventional MTD method is compared.

Reasonable financing structure is of great significance to the healthy development of enterprises. It can improve the operation and management of enterprises, enhance the financing ability of enterprises and promote the effective allocation of market resources. In this paper, the analysis of the capital structure of Sichuan Changhong found that the capital structure of Sichuan Changhong is not reasonable enough, in view of this problem to put forward some suggestions and improvement measures, not only can make Sichuan Changhong close to the optimal capital structure, improve its own quality and investment value, but also can enhance investors’ confidence in Sichuan Changhong.

Li−O2 batteries with bis(trifluoromethanesulfonyl)imide‐based ionic liquid (TFSI‐IL) electrolyte are promising because TFSI‐IL can stabilize O2− to lower charge overpotential. However, slow Li+ transport in TFSI‐IL electrolyte causes inferior Li deposition. Here we optimize weak solvating molecule (anisole) to generate anisole‐doped ionic aggregate in TFSI‐IL electrolyte. Such unique solvation environment can realize not only high Li+ transport parameters but also anion‐derived solid electrolyte interface (SEI). Thus, fast Li+ transport is achieved in electrolyte bulk and SEI simultaneously, leading to robust Li deposition with high rate capability (3 mA cm−2) and long cycle life (2000 h at 0.2 mA cm−2). Moreover, Li−O2 batteries show good cycling stability (a small overpotential increase of 0.16 V after 120 cycles) and high rate capability (1 A g−1). This work provides an effective electrolyte design principle to realize stable Li deposition and high‐performance Li−O2 batteries. [ABSTRACT FROM AUTHOR]

Bis(trifluoromethanesulfonyl)imide‐based ionic liquid (TFSI‐IL) electrolyte could endow Li‐O2 batteries with low charging overpotential. However, their weak Li+ transport ability (LTA) leads to non‐uniform Li deposition. Herein, guided by Sand formula, the LTA of TFSI‐IL electrolyte is greatly enhanced to realize robust Li deposition through introducing hydrofluoroether (HFE) and optimizing electrolyte component ratios to regulate solvation environment. The solvation environment changes from Li(TFSI)2− ion pair into ionic aggregate clusters in the optimal electrolyte thanks to the slicing function of HFE toward ionic aggregate network. The transport parameters of Sand formula are synchronously enhanced, resulting in highly robust Li deposition behavior with greatly improved Coulombic efficiency (ca. 97.5 %) and cycling rate (1 mA cm−2). Cycling stability of Li‐O2 batteries was greatly improved (a tiny overpotential rise of 64 mV after 75 cycles). [ABSTRACT FROM AUTHOR]