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Adaptive synchronization of a class of chaotic systems via variable structure control

第二十三届中国控制会议

作者： zhang xinying, guan xinping, li huiguang (Institute of Electrical Engineering, Yanshan University, Qinhuangdao 066004)

＜正＞ A controller design for a class of chaotic systems subject to nonlinear input is considered in this paper. It is guaranteed that, when some mild assumptions are satisfied, the synchronization between the drive system and the response system can be achieved with the proposed control law. Simulation results verify the effectiveness.

关键词： chaotic synchronization nonlinear input chaotic system

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Journal of Systems Engineering and Electronics 2005年第4期16卷 858-861,865页

作者： li huiguang zhang xinying guan xinping Inst. of Electrical Engineering Yanshan Univ. Qinhuangdao 066004 P. R. China

The synchronization problem under two cases is considered. One is that the bound on the uncertainty existing in the controller is known, the other is that the bound is unknown. In the latter case, the simple adaptation laws for upper bound on the norm of the uncertainty is proposed. Using this adaptive upper bound, a variable structure control is designed. The proposed method does not guarantee the convergence of the adaptive upper bound to the real one but makes the system asymptotically stable.

关键词： chaotic synchronization uncertainty variable structure control.

Bauschinger Effect of Mn18Cr18N Austenitic Stainless Steel

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 399-406页

作者： li Fei ZHAO Xiaodong zhang Huayu HE Wenwu CHEN Huiqin GUO huiguang School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China School of Elec-tronic Information Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China School of Applied Science Taiyu-an University of Science and TechnologyTaiyuan 030024China

The experimental study of Bauschinger effect in Mn18Cr18N austenitic stainless steel was presented by compression-tensile cyclic loading tests with the prestrains ranging from 0.005 to 0.1,which was illustrated utilizing stress-strain curves and analysed by TEM images from aspects of microstructural ***,the Bauschinger effect and its associated roundness phenomenon in reverse flow curve with respect to different cycles and cyclic strain amplitudes were evaluated in a quantitative *** experimental results indicate that Bauschinger effect is apparent during the *** smaller cyclic strain amplitude,intergranular backstress is the main source of Bauschinger *** further increasing of cycles,dislocation density increases and dislocation movement is hindered in the reverse ***,Bauschinger effect is weakened to some *** large cyclic strain amplitude,backstress originating from the dislocation pile-up at grain boundaries and the continuous formation of deformation twins dominate the Bauschinger *** addition,the backstress results in the roundness of reverse curve during cyclic *** larger value ofΔεp*,the more obvious the roundness of the reverse curve,and the more significant the Bauschinger effect.

关键词： Mn18Cr18N steel bauschinger effect cyclic plastic deformation microstructure evolution

Meso-structure and fracture mechanism of mudstone at high temperature

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International Journal of Mining Science and Technology 2014年第4期24卷 433-439页

作者： zhang lianying Mao Xianbiao liu Ruixueab li Yan Yin huiguang Civil Engineering Department Xuzhou Institute of Technology State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology School of Mechanics & Civil Engineering China University of Mining & Technology

The meso-structure mineral composition and fracture mechanism of uniaxial compressed mudstone samples at high temperature were analyzed by XRD and scanning electron microscopy. The effect of tem- perature on mudstone composition and fracture mechanism were studied from a meso-structural per- spective, and the relationship between meso-structure and macro-mechanical characteristics at high temperature was revealed. The findings demonstrated that the fluctuation in diffraction intensity of kao- linite in the mudstone caused the fluctuation in its mechanical properties. The overall structure under- went a phase change around 600℃, which led to the sudden change in the mechanical properties of mudstone samples. When the temperature reached 600 ℃, the crystalline state worsened and kaolinite disappeared; however, some illite was produced, indicating that the chemical reaction of the structure and sudden drop of bearing capacity of the mudstone. Mudst0ne fracturing at high temperature involves mainly intergranular and transgranular fractures, which are typical in micro-brittle tensile failure. Con- sidering the macro-fracture characteristics of mudstone, the results suggested that macro-fracture under external force corresoonds to the meso-fracture.

关键词： Mudstone Mineral composition SEM Meso-fracture Macro-fracture

Effects of strain rates on mechanical properties of limestone under high temperature

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Mining Science and Technology 2011年第6期21卷 857-861页

作者： Tang Furong Mao Xianbiao zhang lianying Yin huiguang li Yan State Key Laboratory of Geomechanics ＆ Deep Underground Engineering China University of Mining ＆ Technology Xuzhou 221008 China School of Sciences China University of Mining ＆ Technology Xuzhou 221116 China Civil Engineering Department Xuzhou Institute of Technology Xuzhou 221008 China

The experimental tests for limestone specimens at 700 °C in uniaxial compression were carried out to inves- tigate the mechanical effects of loading rates on limestone by using a MTS810 rock mechanics servo- controlled testing system considering the loading rate as a variable. The mechanical properties of limestone such as the stress-strain curve, variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the strain rates ranging from 1.1 10à5 to 1.1 10à1 sà1. (1) Sharp decreases were shown for the peak strength and elastic modulus of limestone from 1.1 10à5 to 1.1 10à4 sà1 at 700 °C as well as a downward trend was shown from 1.1 10à4 to 1.1 10à1 sà1 with the rise of the strain rate. (2) The peak strain increased from 1.1 10à5 to 1.1 10à4 sà1, however, there was no obvious changes shown for the peak strain of limestone from 1.1 10à4 to 1.1 10à1 sà1. These results can provide valuable references for the rock blasting effect and design of mine.

关键词： Strain rates High temperature Mechanical properties limestone

Macroscopic and microscopic fracture features of concrete used in coal mine under chlorine salt erosion

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International Journal of Mining Science and Technology 2016年第3期26卷 455-459页

作者： li Bing Yin huiguang Mao Xianbiao li Yan zhang lianying liu Ruixue Qiu Peitao State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology School of Civil Engineering Xuzhou Institute of Technology School of Mechanics & Civil Engineering China University of Mining & Technology

The microscopic morphology and pore structure characteristics of concrete with composite admixtures(fly ash and mineral powder) after chlorine salt erosion were analyzed via scanning electron microscopy(SEM) and mercury injection porosimetry(MIP), providing the basis for the design and maintenance of concrete shafts in coal mines. The above-mentioned characteristics were compared with the macroscopic characteristic of concrete fractures under uniaxial compression. The results show that the macroscopic fracture characteristics of concrete under uniaxial compression change from longitudinal split fracture and oblique section shear fracture to conjugate cant fracture, and the degree of breakage *** cracks, cement paste cracks, spherical surface cracks, and aggregate cracks appear in concrete under uniaxial compression. In the early stages of corrosion, the original cracks which are obvious are repaired. When the corrosion becomes more serious, cement paste cracks appear, and the number of harmful holes increases while the number of harmless holes decreases. This study also reveals the relationship between the macroscopic properties and microscopic structure of concrete under chloride salt erosion. Finally, the paper preliminarily discussed the relationship between the macroscopic properties and mesoscopic characteristics of concrete under chlorine salt erosion.

关键词： Concrete Chlorine salt erosion Mesoscopic characteristic Damage fracture

DEPENDENCE　OF　SINTERABIliTY　ON　STATE　OF　AGGLOMERATION　OF　ULTRAFINE　ZrO_2，（Y_2O_3）　POWDERS

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中国有色金属学会会刊：英文版 1995年第3期5卷 37-40,44页

作者： Rongde, Ge Zhihong, liu huiguang, Chen Duomo, zhang Tiancong, Zhao Central South Univ of Technology Changsha China

ＤＥＲＳＤＥＰＥＮＤＥＮＣＥＯＦＳＩＮＴＥＲＡＢＩＬＩＴＹＯＮＳＴＡＴＥＯＦＡＧＧＬＯＭＥＲＡＴＩＯＮＯＦＵＬＴＲＡＦＩＮＥＺｒＯ_２，（Ｙ_２Ｏ_３）ＰＯＷＤＥＲＳ￥Ｇｅ，Ｒｏｎｇｄｅ；Ｌｉｕ，Ｚｈｉｈｏｎｇ；Ｃｈｅ... 详细信息

ＤＥＲＳＤＥＰＥＮＤＥＮＣＥＯＦＳＩＮＴＥＲＡＢＩＬＩＴＹＯＮＳＴＡＴＥＯＦＡＧＧＬＯＭＥＲＡＴＩＯＮＯＦＵＬＴＲＡＦＩＮＥＺｒＯ_２，（Ｙ_２Ｏ_３）ＰＯＷＤＥＲＳ￥Ｇｅ，Ｒｏｎｇｄｅ；Ｌｉｕ，Ｚｈｉｈｏｎｇ；Ｃｈｅｎ，Ｈｕｉｇｕａｎｇ；Ｚｈａｎｇ，...

关键词： zirconia ultrafine powder agglomeration sinterability

A conserved structural motif shared by EIAV gp90 and HIV gp120

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Chinese Science Bulletin 2005年第20期50卷 2393-2394页

作者： li huiguang TONG Xiao SHEN Tao SHEN Rongxian zhang Xiaoyan SHAO Yiming Department of Research on Virology and Immunology National Center for AIDS/STD Control and Prevention CDC Beijing 100052 China Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China Department of Research on EIAV Harbin Veterinary Research Institute Harbin 150001 China

Both HIV and EIAV belong to the retroviridae family and lentivirus genus. They share considerable simi- larity at gene structural and component level. Hotzel pro- posed that two variable regions and surrounding amino acids of EIAV gp90 might adopt the same topology as V1, V2 and bridging sheet of HIV gp120. These regions map to V3, V4 and surrounding amino acids of EIAV gp90. Based on this proposal, we further analyzed the distribution profile of N-glycosylation site and linear epitope for EIAV gp90 and HIV gp120 at these regions. Our results demonstrated that EIAV gp90 and HIV gp120 are highly similar at these two aspects. Most likely, V3, V4 and surrounding amino acids of EIAV gp90 adopt the same topology structure as V1, V2 and bridging sheet of HIV gp120.

关键词： HIV 爱滋病病毒传染病传播途径基因结构

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离散混沌系统同步的新问题

吉林大学学报（工学版） 2004年第Z1期34卷 106-109页

作者：李惠光张新莹关新平燕山大学电气工程学院河北秦皇岛066004

研究了控制器存在不确定性时一类离散混沌系统的同步问题.采用本文设计的控制器,只要不确定性的上界满足一定的条件,不需要知道不确定性的数据信息就可以有效地实现同步.仿真结果表明了本文控制策略的有效性.

关键词：混沌同步离散混沌系统不确定性