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Exact Solitary-wave Solutions and Periodic Wave Solutions for Generalized Modified Boussinesq Equation and the Effect of Wave Velocity on Wave Shape

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 691-705页

作者： wei-guo zhang Shao-wei Li wei-zhong Tian Lu zhang College of Science University of Shanghai for Science and Technology Shanghai 200093 China School of mathematics and information engineering Taizhou university Zhejiang 317300 China

By means of the undetermined assumption method, we obtain some new exact solitary-wave solutions with hyperbolic secant function fractional form and periodic wave solutions with cosine function form for the generalized modified Boussinesq equation. We also discuss the boundedness of these solutions. More over, we study the correlative characteristic of the solitary-wave solutions and the periodic wave solutions along with the travelling wave velocity＇s variation.

关键词： Generalized modified Boussinesq equation exact solitary-wave solution periodic wave solution

Aldol Reactions Catalyzed by Proline Functionalized Polyacrylonitrile Fiber

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Chemical Research in Chinese Universities 2013年第2期29卷 256-262页

作者： XIAO Jia LI guo-wei zhang Wen-qin Department of Chemistry School of Sciences Tianjin University Tianjin 300072 P. R. China

A proline functionalized fiber catalyst was employed for aldol reactions in water. In the presence of the fiber catalyst, the aldol reactions proceeded smoothly at 40 ℃ and the products were obtained in excellent yields which were higher than those obtained for the reactions catalyzed by L-proline or trans-4-hydroxy-L-proline. This newly developed fiber catalyst is applicable to the reactions of a wide range of aromatic aldehydes and exhibits ex- cellent reusability（up to 6 times） without any additional treatment.

关键词： Polyacrylonitrile fiber(PANF) Proline Aldol reaction Supported catalyst

Approximate Damped Oscillatory Solutions for Compound KdV-Burgers Equation and Their Error Estimates

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 305-324页

作者： wei-guo zhang Yan ZHAO Xiao-yan TENG School of Science University of Shanghai for Science and Technology Shanghai 200093 China College of Mathematics and Physics Nanjing University of Information Science and TechnologyNanjing 210044 China College of Foundation Shanghai University of Engineering Science Shanghai 201600 China

In this paper, we focus on studying approximate solutions of damped oscillatory solutions of the compound KdV-Burgers equation and their error estimates. We employ the theory of planar dynamical systems to study traveling wave solutions of the compound KdV-Burgers equation. We obtain some global phase portraits under different parameter conditions as well as the existence of bounded traveling wave solutions. Furthermore, we investigate the relations between the behavior of bounded traveling wave solutions and the dissipation coefficient r of the equation. We obtain two critical values of r, and find that a bounded traveling wave appears as a kink profile solitary wave if │r│ is greater than or equal to some critical value, while it appears as a damped oscillatory wave if │r│is less than some critical value. By means of analysis and the undetermined coefficients method, we find that the compound KdV-Burgers equation only has three kinds of bell profile solitary wave solutions without dissipation. Based on the above discussions and according to the evolution relations of orbits in the global phase portraits, we obtain all approximate damped oscillatory solutions by using the undetermined coefficients method. Finally, using the homogenization principle, we establish the integral equations reflecting the relations between exact solutions and approximate solutions of damped oscillatory solutions. Moreover, we also give the error estimates for these approximate solutions.

关键词： compound KdV-Burgers equation qualitative analysis solitary wave solution damped oscillatorysolution error estimate

Autonomous maneuver decision-making for a UCAV in short-range aerial combat based on an MS-DDQN algorithm

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Defence Technology（防务技术） 2022年第9期18卷 1697-1714页

作者： Yong-feng Li Jing-ping Shi wei Jiang wei-guo zhang Yong-xi Lyu School of Automation Northwestern Polytechnical UniversityXi'an 710129China Shaanxi Province Key Laboratory of Flight Control and Simulation Technology Xi'an 710129China

To solve the problem of realizing autonomous aerial combat decision-making for unmanned combat aerial vehicles(UCAVs) rapidly and accurately in an uncertain environment, this paper proposes a decision-making method based on an improved deep reinforcement learning(DRL) algorithm: the multistep double deep Q-network(MS-DDQN) algorithm. First, a six-degree-of-freedom UCAV model based on an aircraft control system is established on a simulation platform, and the situation assessment functions of the UCAV and its target are established by considering their angles, altitudes, environments, missile attack performances, and UCAV performance. By controlling the flight path angle, roll angle, and flight velocity, 27 common basic actions are designed. On this basis, aiming to overcome the defects of traditional DRL in terms of training speed and convergence speed, the improved MS-DDQN method is introduced to incorporate the final return value into the previous steps. Finally, the pre-training learning model is used as the starting point for the second learning model to simulate the UCAV aerial combat decision-making process based on the basic training method, which helps to shorten the training time and improve the learning efficiency. The improved DRL algorithm significantly accelerates the training speed and estimates the target value more accurately during training, and it can be applied to aerial combat decision-making.

关键词： Unmanned combat aerial vehicle Aerial combat decision Multi-step double deep Q-network Six-degree-of-freedom Aerial combat maneuver library

Exact Periodic Solutions to Generalized BBM Equation and Relevant Conclusions

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 509-516页

作者： Jun-ying An wei-guo zhang University of Shanghai for Science and Technology Shanghai 200093 China

In this paper, we consider generalized BBM equation with nonlinear terms of high *** the case of p=1/2, p=1 and p=2, the exact periodic solutions to G-BBM equation are obtained by means of proper transformation, which degrades the order of nonlinear terms. And we prove that if p ≠ 1/2,p ≠ 1 or p ≠ 2, G-BBM equation does not exist this kind of periodic solution.

关键词： Jacobi elliptic function nonlinear evolution equation periodic solutions

Preparation of pH-and reductive-responsive prodrug nanoparticles via polymerization-induced self-assembly

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Science China Chemistry 2018年第9期61卷 1159-1166页

作者： Miao Chen wei-guo zhang Jia-wei Li Chun-Yan Hong Wen-Jian zhang Ye-Zi You CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China The First Affiliated Hospital of Xinxiang Medical University Xinxiang 453100 China

pH-and reductive-responsive prodrug nanoparticles are constructed via a highly efficient strategy, polymerization-induced selfassembly(PISA). First, reversible addition-fragmentation chain transfer(RAFT) polymerization of 2-(diisopropylamino) ethyl methacrylate(DIPEMA) and camptothecin prodrug monomer(CPTM) using biocompatible poly(N-(2-hydroxypropyl) methacrylamide)(PHPMA-CPDB) as the macro RAFT agent is carried out, forming prodrug diblock copolymer PHPMA-P(DIPEMA-co-CPTM). Then, simultaneous fulfillment of polymerization, self-assembly, and drug encapsulation are achieved via RAFT dispersion polymerization of benzyl methacrylate(Bz MA) using the PHPMA-P(DIPEMA-co-CPTM) as the macro RAFT agent. The prodrug nanoparticles have three layers, the biocompatible shell(PHPMA), the drug-conjugated middle layer(P(DIPEMA-co-CPTM)) and the PBz MA core, and relatively high concentration(250 mg/g). The prodrug nanoparticles can respond to two stimuli(reductive and acidic conditions). Due to reductive microenvironment of cytosol, the cleavage of the conjugated camptothecin(CPT) within the prodrug nanoparticles could be effectively triggered. p H-Induced hydrophobic/hydrophilic transition of the PDIPEMA chains results in faster diffusion of GSH into the CPTM units, thus accelerated release of CPT is observed in mild acidic and reductive conditions. Cell viability assays show that the prodrug nanoparticles exhibit well performance of intracellular drug delivery and good anticancer activity.

关键词： polymerization-induced self-assembly pH-responsive reductive-responsive drug delivery

Qualitative Analysis and Approximate Damped Oscillatory Solutions for a Kind of Nonlinear Dispersive-dissipative Equation

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 1-24页

作者： Shao-wei LI wei-guo zhang Van ZHAO Zheng-ming LI Xiang LI Business School University of Shanghai for Science and Technology Shanghai 200093 China School of Mathematics and Information Engineering Taizhou University Taizhou 317000 China College of Science University of Shanghai for Science and Technology Shanghai 200093 China

This paper makes qualitative analysis to the bounded traveling wave solutions for a kind of nonlinear dispersive-dissipative equation, and considers its solving problem. The relation is investigated between behavior of its solution and the dissipation coefficient. Further, all approximate damped oscillatory solutions when dissipation coefficient is small are presented by utilizing the method of undetermined coefficients according to the theory of rotated vector field in planar dynamical systems. Finally, error estimate is given by establishing the integral equation which reflects the relation between approximate and exact damped oscillatory solutions applying the idea of homogenization principle.

关键词： nonlinear dispersive-dissipative equation qualitative analysis solitary wave solution dampedoscillatory solution error estimate

Asymptotic Stability of Monotone Decreasing Kink Profile Solitary Wave Solutions for Generalized KdV-Burgers Equation

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 475-490页

作者： wei-guo zhang Wen-xia LI Sheng-er DENG Xiang LI College of Science University of Shanghai for Science and Technology

In this paper,we focus on studying the asymptotic stability of the monotone decreasing kink profile solitary wave solutions for the generalized KdV-Burgers *** obtain the estimate of the firstorder and second-order derivatives for monotone decreasing kink profile solitary wave solutions,and overcome the difficulties caused by high-order nonlinear terms in the generalized KdV-Burgers equation in the estimate by using L2 energy estimating method and Young *** prove that the monotone decreasing kink profile solitary wave solutions are asymptotically stable in ***,we obtain the decay rate of the perturbationψin the sense of L^2 and L^∞norm,respectively,which are(1+t)^-1/2 and(1+t)^-1/4 by using Gargliado-Nirenberg inequality.

关键词： Generalized KdV-Burgers equation a priori estimate asymptotic stability decay rate

Interactive Genetic Algorithms with Fitness Adjustment

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Journal of China University of Mining and Technology 2006年第4期16卷 480-484页

作者： guo Guang-song GONG Dun-wei HAO guo-sheng zhang Yong School of lnformation ＆ Electronic Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Noises widely exist in interactive genetic algorithms. However, there is no effective method to solve this problem up to now. There are two kinds of noises, one is the noise existing in visual systems and the other is resulted from user’s preference mechanisms. Characteristics of the two noises are presented aiming at the application of interac- tive genetic algorithms in dealing with images. The evolutionary phases of interactive genetic algorithms are determined according to differences in the same individual’s fitness among different generations. Models for noises in different phases are established and the corresponding strategies for reducing noises are given. The algorithm proposed in this paper has been applied to fashion design, which is a typical example of image processing. The results show that the strategies can reduce noises in interactive genetic algorithms and improve the algorithm’s performance effectively. However, a further study is needed to solve the problem of determining the evolution phase by using suitable objective methods so as to find out an effective method to decrease noises.

关键词： genetic algorithms interactive genetic algorithms noises strategies for reducing noises