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Boundary Control of Coupled Non-Constant Parameter Systems of Time Fractional PDEs with Different-Type Boundary Conditions

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Journal of Systems Science & Complexity 2023年第1期36卷 273-293页

作者： CHEN juan ZHUANG Bo Aliyun School of Big Data Changzhou UniversityChangzhou 213164China School of Information Engineering Binzhou UniversityBinzhou 256600China

This paper addresses a boundary state feedback control problem for a coupled system of time fractional partial differential equations(PDEs)with non-constant(space-dependent)coefficients and different-type boundary conditions(BCs).The BCs could be heterogeneous-type or ***,this coupled system has different BCs at the uncontrolled side for heterogeneous-type and the same BCs at the uncontrolled side for *** main contribution is to extend PDE backstepping to the boundary control problem of time fractional PDEs with space-dependent parameters and different-type *** the backstepping transformation and the fractional Lyapunov method,the Mittag-Leffler stability of the closed-loop system is obtained.A numerical scheme is proposed to simulate the fractional case when kernel equations have not an explicit solution.

关键词： Boundary control coupled systems heterogeneous mittag-leffler stability time fractional PDEs with space-dependent coefficients

运动疗法对前交叉韧带重建后康复疗效影响的网状Meta分析

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中国组织工程研究 2025年第8期29卷 1714-1726页

作者：王娟王广兰左会武武汉体育学院运动医学院湖北省武汉市430079

目的:运动干预被认为是前交叉韧带重建后康复的基础。然而,关于何种运动疗法在改善前交叉韧带重建后患者膝关节肌肉力量和功能方面更有效,目前仍未得出明确结论。为此,文章采用网状Meta分析方法,比较运动疗法治疗前交叉韧带重建后的疗效... 详细信息

目的:运动干预被认为是前交叉韧带重建后康复的基础。然而,关于何种运动疗法在改善前交叉韧带重建后患者膝关节肌肉力量和功能方面更有效,目前仍未得出明确结论。为此,文章采用网状Meta分析方法,比较运动疗法治疗前交叉韧带重建后的疗效,为选择最佳运动疗法提供循证医学依据。方法:计算机检索PubMed,Web of Science,Embase,The Cochrane Library及EBSCO数据库运动疗法治疗前交叉韧带重建后的随机对照试验,检索时限均从建库至2023-11-20。结局指标包括股四头肌肌力、腘绳肌肌力、膝关节功能评分3个连续性变量。运用EndNote X9.1软件筛选文献。采用Cochrane风险偏倚评估工具对纳入的文献进行质量评价,根据GRADE评分对文章结果的证据强度进行评级,采用Stata 16.0进行网状Meta分析。结果:①共纳入36项随机对照试验,包括1179例前交叉韧带重建后患者,纳入文献整体质量中等;涉及9种运动疗法:等速训练、交叉训练、离心训练、水中康复、血流限制训练、运动控制训练、增强式训练、全身振动训练和综合训练;对照措施为常规康复训练。②网状Meta分析结果显示:与常规康复训练相比,离心训练(SMD=2.08,95%CI:0.56-3.60,P=0.007)对前交叉韧带重建后患者股四头肌肌力的改善效果最佳,其次是综合训练(SMD=1.69,95%CI:0.11-3.27,P=0.249)和全身振动训练(SMD=0.81,95%CI:0.11-1.51,P=0.042);在提升患者腘绳肌肌力方面,综合训练(SMD=2.08,95%CI:0.30-3.86,P=0.022)效果最佳,其次是增强式训练(SMD=1.51,95%CI:0.18-2.84,P=0.026)和等速训练(SMD=1.37,95%CI:0.06-2.67,P=0.039);综合训练(SMD=4.60,95%CI:2.40-6.80,P<0.001)改善膝关节功能评分最有效,其次是离心训练(SMD=1.75,95%CI:0.24-3.25,P=0.023)和水中康复(SMD=1.65,95%CI:0.07-3.24,P=0.041)。结论:低到中等强度的临床证据证实,在改善前交叉韧带重建后患者膝关节肌肉力量和功能方面,综合训练可能是最有效的运动疗法,其次是离心训练、增强式训练、等速训练、全身振动训练、水中康复。未来仍需更多高质量的临床随机对照试验来验证结论的可靠性。

关键词：运动疗法前交叉韧带前交叉韧带重建肌肉力量股四头肌肌力腘绳肌肌力膝关节功能随机对照试验网状Meta分析

A Note on the Stability of Geodesics on Diffeomorphism Groups with One-side Invariant Metric

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Acta Mathematica Sinica,English Series 2020年第5期36卷 620-630页

作者： Li juan ZHOU School of Mathematical Sciences Inner Mongolia UniversityHohhot 0010021P.R.China

In this note,we consider the stability of geodesics on volume-preserving diffeomorphism groups with one-side invariant *** showed that for non-Beltrami fields on a three-dimensional compact manifold,there does not exist Eulerian stable flow which is Lagrangian exponential *** noticed that a stationary flow corresponding to the KdV equation can be Eulerian stable while the corresponding motion of the fluid is at most exponentially unstable.

关键词： Volume-preserving diffeomorphism group Bott-Virasoro group Euler equation geodesic Eulerian instability Lagrangian instability

Study on Diameter Controlled Growth of Carbon Nanotubes by LaAl_(1-x)Fe_xO_3 Catalysts

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Chemical Research in Chinese Universities 2005年第1期21卷 4-7页

作者： PENGFeng WANGHong-juan DepartmentofChemicalEngineering SouthChinaUniversityofTechnologyGuangzhou510640P.R.China

A series of LaAl 1-xFe xO 3 catalysts prepared with lanthanum nitrate, aluminium nitrate and iron nitrate was investigated in catalytical syntheses of carbon nanotubes with high yields and purity. The properties of carbon nanotubes prepared by the method of CVD(chemical vapor deposition) with n-hexane as the carbon resource were studied and it was shown that the diameter of carbon nanotubes can be controlled by the molar ratio of iron to aluminum in the catalysts and that the diameter of carbon nanotubes changes a little with the decrease of the iron content in the catalysts. From the TEM pictures of carbon nanotubes, it can be found that the LaAl 1-xFe xO 3 catalysts have a significant influence on the wall thickness of the carbon nanotubes, whereas they have little influence on the inner diameter of the carbon nanotubes.

关键词： Carbon nanotube LaAl1-xFexO3 Chemical vapor deposition Diameter controlled Catalyst

Predicting Natural and Chaotic Time Series with a Swarm-Optimized Neural Network

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Chinese Physics Letters 2011年第11期28卷 38-40页

作者： juan A Lazzús Departamento de Física Universidad de La SerenaCasilla 554La SerenaChile

Natural and chaotic time series are predicted using an artificial neural network(ANN)based on particle swarm optimization(PSO).Firstly,the hybrid ANN+PSO algorithm is applied on Mackey–Glass series in the short-term prediction𝑥(𝑡+6),using the current value𝑥(𝑡)and the past values:𝑥(𝑡−6),𝑥(𝑡−12),𝑥(𝑡−18).Then,this method is applied on solar radiation data using the values of the past years:𝑥(𝑡−1),...,𝑥(𝑡−4).The results show that the ANN+PSO method is a very powerful tool for making predictions of natural and chaotic time series.

关键词： series chaotic method

Overview of Rubik's Cube and Reflections on Its Application in Mechanism

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 9-20页

作者： Da-Xing Zeng Ming Li juan-juan Wang Yu-Lei Hou Wen-juan Lu Zhen Huang School of Mechanical Engineering Yanshan University

Rubik’s Cube is a widely popular mechanical puzzle that has attracted attention around the world because of its unique characteristics. As a classic brain-training toy well known to the public, Rubik’s Cube was used for scientific research and technology development by many scholars. This paper provides a basic understanding of the Rubik’s Cube and shows its mechanical art from the aspects of origin and development, characteristics, research status and especially its mechanical engineering design, as well as making a vision for the application in mechanism. First, the invention and origin of Rubik’s Cube are presented, and then the special characteristics of the cube itself are *** that, the present researches of Rubik’s Cube are reviewed in various disciplines at home and abroad, including the researches of Rubik’s Cube scientific metaphors, reduction algorithms, characteristic applications, and mechanism issues. Finally, the applications and prospects of Rubik’s Cube in the field of mechanism are discussed.

关键词： Rubik's Cube Scientific research Mechanical art Application and prospects

Synergistic and interference effects in coaxial mixers: Numerical analysis of the power consumption

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Chinese Journal of Chemical Engineering 2018年第4期26卷 684-694页

作者： juan Huang Gance Dai School of Perfume and Aroma Technology Shanghai Institute of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

This paper is concerned with the design and application of coaxial mixers with the aid of analysis of interaction between each individual impeller. Two types of coaxial mixers pitched blade turbine(PBT)-helical ribbon(HR)and inner-outer HR operated in laminar regime were studied experimentally and numerically. The interaction implies synergistic and interference effects, which was revealed through the investigation of axial circulation rate, energy dissipation rate and power consumption. The influence factors including rotational speed ratio,rotating mode and impeller configuration were explored systematically. Quantitative analysis of power consumption involves three parameters: rate of variation in power consumption, interactive mode and ratio of power consumption. Analysis indicated that some important properties were embodied in the power *** properties are one-way and two-way interactions, critical speed ratio and dominant impeller. Finally, a new suggestion for power estimation was given.

关键词： Numerical simulation Mixing Laminar flow Coaxial mixers Power consumption Interaction

NEW RESULTS ABOUT THE RELATIONSHIP BETWEEN OPTIMALLY WEIGHTED LEAST SQUARES ESTIMATE AND LINEAR MINIMUM VARIANCE ESTIMATE

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Journal of Systems Science & Complexity 2009年第1期22卷 137-149页

作者： juan ZHAO Yunmin ZHU Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China. Department of Mathematics Sichuan University Chengdu 610064 China.

The optimally weighted least squares estimate and the linear minimum variance estimateare two of the most popular estimation methods for a linear *** this paper,the authors makea comprehensive discussion about the relationship between the two ***,the authorsconsider the classical linear model in which the coefficient matrix of the linear model is deterministic,and the necessary and sufficient condition for equivalence of the two estimates is ***,under certain conditions on variance matrix invertibility,the two estimates can be identical providedthat they use the same a priori information of the parameter being ***,the authorsconsider the linear model with random coefficient matrix which is called the extended linear model;under certain conditions on variance matrix invertibility,it is proved that the former outperforms thelatter when using the same a priori information of the parameter.

关键词： Conditional expectation linear minimum variance estimation necessary and sufficient condition optimally weighted least squares estimation.

Intramolecular proton transfer: a reliable solution to design all-visible-light-activated dithienylethenes

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Science China Chemistry 2020年第4期63卷 421-422页

作者： Keitaro Nakatani juan Xie Universite Paris-Saclay ENS Paris-SaclayCNRSPPSM61 av.du President Wilson94235 CachanFrance

In the fields of materials science and life science,the ability to influence key properties of molecular systems by using light is of great *** compounds play a key role in such systems since they can reversibly photoisomerize between two states[1].Among photochromic series,dithienylethenes(DTEs)can undergo reversible conrotatory 671 photocyclization and cycloreversion have drawn much attention due to the excellent thermal irreversibility and outstanding fatigue resistance[2].

关键词： fatigue resistance visible