Civil Aviation University of China

About: Civil Aviation University of China is a education organization based out in Tianjin, China. It is known for research contribution in the topics: Air traffic control & Civil aviation. The organization has 5647 authors who have published 4559 publications receiving 29825 citations. The organization is also known as: Zhōngguó Mínháng Dàxué.

Interval Neutrosophic Prioritized OWA Operator and Its Application to Multiple Attribute Decision Making

Abstract: On the basis of prioritized aggregated operator and prioritized ordered weighted average (POWA) operator, in this paper, the authors further present interval neutrosophic prioritized ordered weighted aggregation (INPOWA) operator with respect to interval neutrosophic numbers (INNs). Firstly, the definition, operational laws, characteristics, expectation and comparative method of INNs are introduced. Then, the INPOWA operator is developed, and some properties of the operator are analyzed. Furthermore, based on the INPOWA operator and the comparative formula of the INNs, an approach to decision making with INNs is established. Finally, an illustrative example is given to verify the developed approach and to demonstrate its practicality and effectiveness.

Isolated copper single sites for high-performance electroreduction of carbon monoxide to multicarbon products.

Abstract: Electrochemical carbon monoxide reduction is a promising strategy for the production of value-added multicarbon compounds, albeit yielding diverse products with low selectivities and Faradaic efficiencies. Here, copper single atoms anchored to Ti3C2Tx MXene nanosheets are firstly demonstrated as effective and robust catalysts for electrochemical carbon monoxide reduction, achieving an ultrahigh selectivity of 98% for the formation of multicarbon products. Particularly, it exhibits a high Faradaic efficiency of 71% towards ethylene at −0.7 V versus the reversible hydrogen electrode, superior to the previously reported copper-based catalysts. Besides, it shows a stable activity during the 68-h electrolysis. Theoretical simulations reveal that atomically dispersed Cu–O3 sites favor the C–C coupling of carbon monoxide molecules to generate the key *CO-CHO species, and then induce the decreased free energy barrier of the potential-determining step, thus accounting for the high activity and selectivity of copper single atoms for carbon monoxide reduction. Electrochemical carbon monoxide reduction is a promising strategy to yield valuable multicarbon products but low selectivities and Faradaic efficiencies are common. Here the authors show single atom copper catalyst supported on MXene with high CO reduction performance and stability.

Real-Time Trajectory and Attitude Coordination Control for Reusable Launch Vehicle in Reentry Phase

Abstract: The real-time reentry trajectory and attitude coordination control for a reusable launch vehicle (RLV) is a very important and challenging problem. There are many aspects that make the research appealing, such as being able to autonomously replan a new trajectory onboard when the landing site is changed. In order to achieve the goal, an integrated guidance and control architecture is proposed in this paper. First, the offline reentry trajectory is designed based on adaptive Gauss pseudospectral method. Then, the obtained trajectory is used as the initial value guess for real-time reentry trajectory optimization. As a result, the pseudospectral-based optimal feedback reentry guidance is achieved via successive real-time optimal open-loop control which ensures that the guidance system has sufficient robustness for initial reentry perturbations. Furthermore, a multitime scale smooth second-order sliding-mode controller with disturbance observer is proposed to ensure the finite-time reentry attitude tracking despite the model parameter uncertainties and unknown external disturbances. Finally, two representative simulation tests are carried out to demonstrate the effectiveness of the proposed integrated guidance and control architecture for six-degree-of-freedom RLV.

Fractional Kirchhoff problems with critical Trudinger–Moser nonlinearity

Abstract: This paper is concerned with the existence of solutions for a class of fractional Kirchhoff-type problems with Trudinger–Moser nonlinearity: $$\begin{aligned} {\left\{ \begin{array}{ll} M\left( \displaystyle \iint _{{\mathbb {R}}^{2N}}\frac{|u(x)-u(y)|^{N/s}}{|x-y|^{2N}}dxdy\right) (-\Delta )^{s}_{N/s}u=f(x,u)\,\, \ &{}\quad \mathrm{in}\ \Omega ,\\ u=0\ \ \ \ &{}\quad \mathrm{in}\ {\mathbb {R}}^N{\setminus } \Omega , \end{array}\right. } \end{aligned}$$ where $$(-\Delta )^{s}_{N/s}$$ is the fractional N / s-Laplacian operator, $$N\ge 1$$ , $$s\in (0,1)$$ , $$\Omega \subset {\mathbb {R}}^N$$ is a bounded domain with Lipschitz boundary, $$M:{\mathbb {R}}^+_0\rightarrow {\mathbb {R}}^+_0$$ is a continuous function, and $$f:\Omega \times {\mathbb {R}}\rightarrow {\mathbb {R}} $$ is a continuous function behaving like $$\exp (\alpha t^{2})$$ as $$t\rightarrow \infty $$ for some $$\alpha >0$$ . We first obtain the existence of a ground state solution with positive energy by using minimax techniques combined with the fractional Trudinger–Moser inequality. Next, the existence of nonnegative solutions with negative energy is established by using Ekeland’s variational principle. The main feature of this paper consists in the presence of a (possibly degenerate) Kirchhoff model, combined with a critical Trudinger–Moser nonlinearity.