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Function Projective Lag Synchronization of Chaotic Systems with Certain Parameters via Adaptive-impulsive Control

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International Journal of Automation and computing 2019年第2期16卷 238-247页

作者： Xiu-Li chai Zhi-hua Gan Institute of Image Processing and Pattern Recognition Henan University Institute of Intelligent Network System School of SoftwareHenan University

A new method is presented to study the function projective lag synchronization(FPLS) of chaotic systems via adaptive-impulsive control. To achieve synchronization, suitable nonlinear adaptive-impulsive controllers are designed. Based on the Lyapunov stability theory and the impulsive control technology, some effective sufficient conditions are derived to ensure the drive system and the response system can be rapidly lag synchronized up to the given scaling function matrix. Numerical simulations are presented to verify the effectiveness and the feasibility of the analytical results.

关键词： Function projective lag synchronization (FPLS) adaptive-impulsive chaotic systems numerical simulation Lyapunov stability theory

Release Behavior of Sulfur during Fluidized Bed Gasification

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Journal of Thermal Science 2021年第5期30卷 1731-1740页

作者： XIAN Shengxian ZHANG Haixia chai zhen JIANG Denghao ZHU Zhiping Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

During fluidized bed gasification,sulfur in coal will be released,which will lead to environmental *** release behavior of sulfur in fluidized bed gasification has not been fully studied,although fluidized bed gasification technology has a promising *** the release behaviors of sulfur during fluidized bed gasification were investigated comprehensively through two aspects:temperature and reaction *** air gasification,the main gaseous sulfur is H_(2)S,followed by COS,and the yield of SO_(2)and CS_(2)is *** the increase of temperature,both of the released sulfur and the percentage of inorganic sulfur in gas phase *** the same working condition,the distributions of sulfur forms in gasification residues are *** sulfur is the dominate sulfur forms in the gasification *** in residues increases while organic sulfur decreases with increasing *** three reaction atmospheres(CO_(2)/steam/air)studied,the yield of H_(2)S is the most among the above four kinds of gaseous *** percentage of H_(2)S in gaseous sulfur(H_(2)S/Sg)is the highest in the process of steam gasification,while most sulfur is released during air *** sequencing of H_(2)/CO is the same as that of H_(2)S/Sg,while the trend of sulfur release rate is consistent with that of carbon conversion *** distributions of sulfur species in the fly ash of CO_(2)gasification and steam gasification are similar,while the sulfate content in the fly ash of air gasification is the highest.

关键词： released sulfur fluidized bed gasification temperature reaction atmosphere

Reachable set modeling and engagement analysis of exoatmospheric interceptor

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Chinese Journal of Aeronautics 2014年第6期27卷 1513-1526页

作者： chai hua Liang Yangang Chen Lei Tang Guojin College of Aerospace Science and Engineering National University of Defense Technology

A novel reachable set（RS） model is developed within a framework of exoatmospheric interceptor engagement analysis. The boost phase steering scheme and trajectory distortion mechanism of the interceptor are firstly explored. A mathematical model of the distorted RS is then formulated through a dimension–reduction analysis. By treating the outer boundary of the RS on sphere surface as a spherical convex hull, two relevant theorems are proposed and the RS envelope is depicted by the computational geometry theory. Based on RS model, the algorithms of intercept window analysis and launch parameters determination are proposed, and numerical simulations are carried out for interceptors with different energy or launch points. Results show that the proposed method can avoid intensive on-line computation and provide an accurate and effective approach for interceptor engagement analysis. The suggested RS model also serves as a ready reference to other related problems such as interceptor effectiveness evaluation and platform disposition.

关键词： Engagement analysis Flight dynamics Interception Reachable set Spherical convex hull

Interfacial Structures Governed Plastic Deformation Behaviors in Metallic Multilayers

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 199-204页

作者： Ming-zhen Wei zhen-hua Cao Xiang-Kang Meng Institute of Materials Engineering National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Department of Physics School of Science Linyi University

In this work, we have investigated the mechanical properties of Cu/Ta, Ag/Cu and Ag/Nb multilayers with different heterogeneous interfaces. The results suggest that when individual layer thickness （h） is larger than 5-10 nm, the hardness/strength of three different multilayer systems has the similar length scale effect with decreasing layer thickness, while when h ≤ 5 nm, the three multilayer systems show remarkably different plastic deformation behaviors. The strength curves exhibit the variation trends of unchanging, softening and increasing corresponding to Cu/Ta, Ag/Cu and Ag/Nb multilayers, respectively. The microstructure analysis shows that three kinds of multilayers have totally different interfacial structures, which lead to the different strengthening or softening mechanisms.

关键词： Metallic multilayers Plastic deformation Interfacial structures Strengthening mechanism

Online Scheduling on Bounded Batch Machines to Minimize the Maximum Weighted Completion Time

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Journal of the Operations Research Society of China 2018年第3期6卷 455-465页

作者： Wen-hua Li Xing chai School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Financial Engineering Zhengzhou 450001China

We investigate the online scheduling problem on identical parallel-batch machines to minimize the maximum weighted completion *** this problem,jobs arrive over time and the processing times(of the jobs)are identical,and the batch capacity is *** this problem,we provide a best possible online algorithm with a competitive ratio of(√5+1)/***,when restricted to dense-algorithms,we present a best possible dense-algorithm with a competitive ratio of 2.

关键词： Scheduling Online algorithms Maximum weighted completion time Competitive ratio

Bifurcation in a Class of Planar Piecewise Smooth Systems with 3-parameters

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Communications in Mathematical Research 2014年第3期30卷 207-221页

作者： LIU YUAN-YUAN chai zhen-hua Ma Fu-ming School of Mathematics Jilin University

This paper is concerned with the bifurcation properties on the line of discontinuity of planar piecewise smooth systems. The existence of equilibria and periodic solutions with sliding motion in a class of planar piecewise smooth systems with 3-parameters is investigated in this paper using the theory of differential inclu-sion and tools of Poincar′e maps.

关键词： piecewise smooth system line of discontinuity equilibria periodic so-lution with sliding motion bifurcation

Towards fully automatic modelling of the fracture process in quasi-brittle and ductile materials:a unified crack growth criterion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 867-877页

作者： zhen-jun YANG Guo-hua LIU College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China

Fully automatic finite element(FE) modelling of the fracture process in quasi-brittle materials such as concrete and rocks and ductile materials such as metals and alloys,is of great significance in assessing structural integrity and presents tre-mendous challenges to the engineering community. One challenge lies in the adoption of an objective and effective crack propagation criterion. This paper proposes a crack propagation criterion based on the principle of energy conservation and the cohesive zone model(CZM) . The virtual crack extension technique is used to calculate the differential terms in the criterion. A fully-automatic discrete crack modelling methodology,integrating the developed criterion,the CZM to model the crack,a simple remeshing procedure to accommodate crack propagation,the J2 flow theory implemented within the incremental plasticity framework to model the ductile materials,and a local arc-length solver to the nonlinear equation system,is developed and im-plemented in an in-house program. Three examples,i.e.,a plain concrete beam with a single shear crack,a reinforced concrete(RC) beam with multiple cracks and a compact-tension steel specimen,are simulated. Good agreement between numerical predictions and experimental data is found,which demonstrates the applicability of the criterion to both quasi-brittle and ductile materials.

关键词： Finite element method (FEM) Crack propagation criterion Cohesive zone model (CZM) Virtual crack extension(VCE) Arc-length method

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碳酸钠与盐酸分步反应pH曲线误差探究

化学教育(中英文) 2025年第3期46卷 86-92页

作者：孟庆华刘茂臻邢蓓蓓刘翠江苏师范大学化学与材料科学学院江苏徐州221116

采用自行搭建的实验装置探究了用数字化技术获得的碳酸钠与盐酸分步反应的pH曲线第1步消耗的盐酸量V_(1)与第2步消耗的盐酸量V_(2)存在差异的原因。实验结果表明V_(1),V_(2)产生差异主要是由搅拌速度、滴定速度、溶液浓度、溶液温度等... 详细信息

采用自行搭建的实验装置探究了用数字化技术获得的碳酸钠与盐酸分步反应的pH曲线第1步消耗的盐酸量V_(1)与第2步消耗的盐酸量V_(2)存在差异的原因。实验结果表明V_(1),V_(2)产生差异主要是由搅拌速度、滴定速度、溶液浓度、溶液温度等条件影响pH传感器对pH响应的滞后效应造成的。在滴定过程中溶液充分搅拌的情况下,滴定速度越快,V_(1)大于V_(2)且差值越大;Na_(2)CO_(3)浓度越高时其溶液黏度越大,使pH传感器对pH响应的滞后效应加剧;溶液温度较高时,溶液黏度降低,使V_(1)与V_(2)差值变小;当Na_(2)CO_(3)浓度较低时,水中溶解的CO_(2)与碳酸钠溶液反应生成的碳酸氢钠量对V_(1)与V_(2)差值的影响不能忽略,配制溶液的纯净水最好煮沸冷却后即用。

关键词：滞后效应 pH传感器分步反应碳酸钠盐酸

A high activity of Ti/SnO_2-Sb electrode in the electrochemicaldegradation of 2,4-dichlorophenol in aqueous solution

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Journal of Environmental Sciences 2013年第7期25卷 1424-1430页

作者： Junfeng Niu Dusmant Maharana Jiale Xu zhen chai Yueping Bao State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University School of Chemical and Environmental Engineering China University of Mining & Technology

Electrochemicaldegradation of2,4-dichlorophenol （2,4-DCP） in aqueous solutionwas investigated over Ti/SnO2-Sb anode. The factors influencing thedegradation rate, such as applied currentdensity （2-40 mA/cm2 ）, pH （3-11） and initial concentration （5-200 mg/L）were evaluated. Thedegradation of2,4-DCP followed apparent pseudo first-order kinetics. Thedegradation ratio on Ti/SnO2 -Sb anode attained 〉 99.9% after 20 min of electrolysis at initial 5-200 mg/L concentrations at a constant currentdensity of 30 mA/cm2 with a 10 mmol/L sodium sulphate （Na2SO4 ） supporting electrolyte solution. The results showed that 2,4-DCP （100 mg/L）degradation and total organic carbon （TOC） removal ratio achieved 99.9% and 92.8%, respectively, at the optimal conditions after 30 min electrolysis. Under this condition, thedegradation rate constant （k） and thedegradation half-life （t1/2 ）were 0.21 min1 and （2.8 ± 0.2） min, respectively. Mainly carboxylic acids （propanoic acid, maleic acid, propanedioic acid, acetic acid and oxalic acid） weredetected as intermediates. The energy efficiencies for2,4-DCPdegradation （5-200 mg/L）with Ti/SnO2-Sb anode ranged from 0.672 to 1.602 g/kWh. The Ti/SnO2-Sb anodewith a high activity to rapid organic oxidation could be employed todegrade chlorophenols, particularly2,4-DCP inwastewater.

关键词： 2 4-dichlorphenol Ti/SnO2 -Sb electrode electrochemicaldegradation total organic carbon