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Extend ethylene aromatization single-event kinetic modeling with physical and chemical descriptor based on ZSM-5 catalyst

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Petroleum Science 2023年第6期20卷 3841-3853页

作者： Jia-rong Xie Fang jin School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan430205HubeiChina Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of TechnologyWuhan430205HubeiChina Novel Reactor&Green Chemical Technology Key Laboratory Wuhan Institute of TechnologyWuhan430205HubeiChina

The ethylene aromatization is critical for the methanol to aromatics and light alkane dehydroaromatization *** single-event microkinetic(SEMK)model combining the linear free energy theory and solid acid distribution concept were established and extend for the ethylene aromatization process,which can reduce the kinetic parameters and simplify the reaction network by comparison with the SEMK model including subtype elementary steps based on the type of carbenium *** introducing deactivation parametersφinto the model and applying the linear free energy model to the deactivation experimental data,the obtained deactivation parametersφindicate that the carbon deposition precursors have the greatest impact on reducing the reaction rate of single-molecular reactions and the smallest impact on the hydrogen transfer ***,according to the change of reaction enthalpy,effect of carbenium ion structure on methylation,ethylation,cyclization and endo-βscission was investigated by introducing linear free energy concept into the SEMK *** effect of different acid strengths on elementary steps was investigated based on the acid strength distribution model,it was found that the methylation and oligomerization reactions,the ali-βscission reaction,endo-βscission reaction and the cyclization reaction were more sensitive to strong acidity *** physisorption and chemisorption heat are separated from the protonation heat in the linear free energy kinetic model and the acid strength distribution kinetic model,and the absolute values of the obtained physisorption and chemisorption heat increase with the carbon number of carbenium ***,the parameters of the acid strength distribution kinetic model were applied to propane dehydroaromatization on H-ZSM-5 and the ethane dehydroaromatization on Zn/ZSM-5 to confirm the independence of parameters in the SEMK model with the similar reaction network.

关键词： Kinetic model Ethylene aromatization Acid strength distribution Linear free energy theory

Generalization of 3D Mandelbrot and Julia sets

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 134-141页

作者： CHENG jin TAN Jian-rong State Key Laboratory of CAD ＆ CG Zhejiang University Hangzhou 310027 China

In order to further enrich the form of 3D Mandelbrot and Julia sets, this paper first presents two methods of generating 3D fractal sets by utilizing discrete modifications of the standard quaternion algebra and analyzes the limitations in them. To overcome these limitations, a novel method for generating 3D fractal sets based on a 3D number system named ternary algebra is proposed. Both theoretical analyses and experimental results demonstrate that the ternary-algebra-based method is superior to any one of the quad-algebra-based methods, including the first two methods presented in this paper, because it is more intuitive, less time consuming and can completely control the geometric structure of the resulting sets. A ray-casting algorithm based on period checking is developed with the goal of obtaining high-quality fractal images and is used to render all the fractal sets generated in our experiments. It is hoped that the investigations conducted in this paper would result in new perspectives for the generalization of 3D Mandelbrot and Julia sets and for the generation of other deterministic 3D fractals as well.

关键词： Mandelbrot set Julia set Fractal Ray-casting Quad algebra Ternary algebra

Upper Bounds for Ruin Probabilities under Stochastic Interest Rate and Optimal Investment Strategies

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1421-1430页

作者： jin Zhu LI rong WU School of Mathematical Sciences and LPMC Nankai University

In this paper, we study the upper bounds for ruin probabilities of an insurance company which invests its wealth in a stock and a bond. We assume that the interest rate of the bond is stochastic and it is described by a Cox-Ingersoll-Ross （CIR） model. For the stock price process, we consider both the case of constant volatility （driven by an O U process） and the case of stochastic volatility （driven by a CIR model）. In each case, under certain conditions, we obtain the minimal upper bound for ruin probability as well as the corresponding optimal investment strategy by a pure probabilistic method.

关键词： Cox Ingersoll-Ross model jump-diffusion model optimal investment Ornstein Uhlen- beck (O-U) process ruin probability stochastic interest rate

The Gerber-Shiu Discounted Penalty Function for a Compound Binomial Risk Model with By-claims

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 181-190页

作者： jin-zhu LI rong WU School of Mathematical Sciences and LPMC Nankai University

A recursive formula of the Gerber-Shiu discounted penalty function for a compound binomial risk model with by-claims is obtained. In the discount-free case, an explicit formula is given. Utilizing such an explicit expression, we derive some useful insurance quantities, including the ruin probability, the density of the deficit at ruin, the joint density of the surplus immediately before ruin and the deficit at ruin, and the density of the claim causing ruin.

关键词： compound binomial risk model Gerber-Shiu function by-claims

Asymptotic Ruin Probabilities of the Renewal Model with Constant Interest Force and Dependent Heavy-tailed Claims

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 329-338页

作者： jin-zhu Li rong Wu School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

In this paper, we investigate the asymptotic behavior for the finite- and infinite-time ruin probabilities of a nonstandard renewal model in which the claims are identically distributed but not necessarily inde- pendent. Under the assumptions that the identical distribution of the claims belongs to the class of extended regular variation （ERV） and that the tails of joint distributions of every two claims are negligible compared to the tails of their margins, we obtain the precise approximations for the finite- and infinite-time ruin probabilities.

关键词： asymptotic behavior extended regular variation negligible joint tails ruin probability

A New Subspace Correction Method for Nonlinear Unconstrained Convex Optimization Problems

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 745-756页

作者： rong-liang CHEN jin-ping ZENG College of Mathematics and Econometrics Hunan University College of Computer Dongguan University of Technology

This paper gives a new subspace correction algorithm for nonlinear unconstrained convex optimization problems based on the multigrid approach proposed by S. Nash in 2000 and the subspace correction algorithm proposed by X. Tai and J. Xu in 2001. Under some reasonable assumptions, we obtain the convergence as well as a convergence rate estimate for the algorithm. Numerical results show that the algorithm is effective.

关键词： nonlinear optimization convergence subspace correction method

Deterministic controlled bidirectional remote state preparation in dissipative environments

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Communications in Theoretical Physics 2022年第7期74卷 72-83页

作者： Jun-rong Gu jin-Ming Liu State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China

It is a significant subject to explore effective quantum communication protocol and enhance the efficiency of the transmission process in noisy environments. In this paper, we investigate the bidirectional controlled remote preparation of an arbitrary single-qubit state in the presence of dissipative environments by using two EPR states as the entanglement source. We first construct the quantum circuit of our scheme by means of unitary matrix decomposition procedure, then the effects of the Markovian and non-Markovian environmental noises acting on the EPR states are considered through the analytical derivation and numerical calculations of the corresponding average fidelity. Moreover, we adopt two methods of weak measurement reversal(WMR) and detuning modulation to improve the average fidelity. Our results show that the average fidelity can be remarkably enhanced under appropriate conditions of the WMR strength and the detuning. Compared with the average fidelity behaviors in dissipative environments, it is also shown that the two methods for fidelity improvement are more efficient in the non-Markovian regime than in the Markovian regime.

关键词： remote state preparation non-Markovian noise fidelity weak measurement reversal

Circulant Double Coverings of a Circulant Graph of Valency Five

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Acta Mathematica Sinica,English Series 2007年第1期23卷 23-28页

作者： rong Quan FENG jin Ho KWAK LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China Mathematics Pohang University of Science and Technology Pohang 790-784 Korea

Enumerating the isomorphism classes of several types of graph covering projections is one of the central research topics in enumerative topological graph theory. A covering of G is called circulant if its covering graph is circulant. Recently, the authors [Discrete Math., 277, 73-85 （2004）1 enumerated the isomorphism classes of circulant double coverings of a certain type, called a typical covering, and showed that no double covering of a circulant graph of valency three is circulant. Also, in [Graphs and Combinatorics, 21,386 400 （2005）], the isomorphism classes of circulant double coverings of a circulant graph of valency four are enumerated. In this paper, the isomorphism classes of circulant double coverings of a circulant graph of valency five are enumerated.

关键词： graph covering voltage assignment Cayley circulant graph

Nonlinear Control Method for Hypersonic Vehicle Based on Double Power Reaching Law of Sliding Mode

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第5期35卷 849-857页

作者： Liu rong Zhang Heng Liang jin Key Laboratory of UAV’s Advanced Technology(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics Key Laboratory of Aircraft Control Integration Technology Aviation Industry Xi’an Flight Automatic Control Research Institute

The intelligence nonlinear control scheme via double power reaching law based sliding mode control method is proposed to solve the problems of model uncertainties and unknown outside ***,the aerodynamic parameters of the morphing vehicle are replaced with curve-fitted approximation to build the accurate model for control design in the hypersonic *** the nonlinear vehicle model is transformed into the strict feedback multi-input/multi-output nonlinear system by using the input-output feedback linearization *** the same time,the disturbance observer is used to approximate the unknown disturbance,and the sliding mode method is used to solve the problem of non-matching and ***,according to the buffeting problem in sliding mode control,the double power is *** results show that the proposed method can ensure the global stability of the closed-loop system,and has good tracking and robust performance.

关键词： hypersonic vehicle disturbance observer double power sliding mode buffeting