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广义Julia集的参数辨识

物理学报 2011年第7期60卷 120-128页

作者：孙洁刘树堂乔威山东大学控制科学与工程学院济南250061 山东大学威海分校机电与信息工程学院威海264209 山东大学威海分校实验室与设备管理处威海264209

本文研究了一类相当广泛的复系统Julia集的参数辨识问题.基于非线性反馈控制器和差分方程稳定性理论,设计了普遍适用的自适应同步控制器和参数自适应律的解析表达式.理论证明设计的控制器可使得此类广义复系统Julia集达到同步,并且可以... 详细信息

本文研究了一类相当广泛的复系统Julia集的参数辨识问题.基于非线性反馈控制器和差分方程稳定性理论,设计了普遍适用的自适应同步控制器和参数自适应律的解析表达式.理论证明设计的控制器可使得此类广义复系统Julia集达到同步,并且可以辨识广义Julia集的未知参数.通过仿真实例验证了该方法的有效性.另外,本文特别地讨论了最基本的Julia集的参数辨识问题.

关键词： Julia集参数辨识同步

Experimental study on a magnetofluid sealing liquid for propeller shaft

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Journal of Marine Science and Application 2003年第1期2卷 66-70页

作者： ZHAO Chang-fa, SUN Rong-hua, ZHENG Jin-xing school of mechanical and electrical engineering, Harbin engineering university, Harbin 150001, china Harbin Institute of technology (china)

The selecting and preparing method of the basic material of magnetic fluid was introduced. By using a chemical method, the magnetic micropowder Fe 3O 4 was successfully yielded, and an oil-base as a working carrier and dispers ing agent was determined. The preparation process of the magnetic fluid and prescription of the oil-base magnetic fluid were discussed. The simulation experimental rig of magnetic fluid sealing for propeller shaft was designed. The sealing ability experiment was conducted and results were analyzed. The pressure of sealing is up to 2 MPa.

关键词： magnetic fluid sealing ability propeller shaft

SIGNAL ESTIMATION WITH BINARY-VALUED SENSORS

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Journal of Systems Science & Complexity 2010年第3期23卷 622-639页

作者： Leyi WANG Gang George YIN Chanying LI Weixing ZHENG Department of electrical and Computer engineering Wayne State University Detroit Michigan 48202 USA Department of Mathematics Wayne State University Detroit Michigan 48202 USA Department of mechanical engineering The University of Hong Kong Pokfulam Road Hong Kong China school of Computing and Mathematics University of Western Sydney Australia

This paper introduces several algorithms for signal estimation using binary-valued *** main idea is derived from the empirical measure approach for quantized identification,which has been shown to be convergent and asymptotically efficient when the unknown parametersare *** estimation under binary-valued observations must take into consideration oftime varying *** empirical measure based algorithms are modified with exponentialweighting and threshold adaptation to accommodate time-varying natures of the *** anyinformation on signal generators,the authors establish estimation algorithms,interaction between noisereduction by averaging and signal tracking,convergence rates,and asymptotic efficiency.A thresholdadaptation algorithm is *** convergence and convergence rates are analyzed by using theODE method for stochastic approximation problems.

关键词： Identification signal estimation.

RESEARCH OF NANOMETER PRECISION POSITIONING STAGE WIThouT FEEDBACK CONTROL

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RESEARCH OF NANOMETER PRECISION POSITIONING STAGE WITHOUT FE...

Deformation Resistance Effect of PAN-based Carbon Fibers

2006年中国机械工程学会年会暨中国工程院机械与运载工程学部首届年会

作者： SUN Shufeng school of mechanical and electrical engineering, Wenzhou university, Wenzhou, Zhejiang Province, 325035, PR china

To adapt the miniaturized development tendency of nanometer positioning devices, a new type of two-dimensional micro-displacement stage which can implement nanometer-level ultra-precision positioning

关键词： Nanometer positioning feedback control flexure plate piezoelectric ceramic actuator(PZTA).

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Journal of Wuhan university of technology(Materials Science) 2009年第3期24卷 415-417页

作者：郑立霞 school of Science Wuhan University of Technology

The deformation resistance effect of polyacrylonitrile （PAN）-based carbon fibers was investigated, and the variatipn law of electrical resistivity under tensile stress was analyzed. The results show that the gauge factor （fractional change in resistance per unit strain） of PAN-based carbon fibers is 1.38, which is lower than that of the commonly-used resistance strain gauge. These may due to that the electrical resistivity of carbon fibers decreases under tensile stress. In addition when the carbon fibers are stretched, the change of its resistance is caused by fiber physical dimension and the change of electric resistivity, and mainly caused by the change of physical dimension. The mechanical properties of carbon fiber monofilament were also measured.

关键词： PAN-based carbon fibers resistance strain gauge factor

Catalyst-free and Reprocessable Aromatic Polydithiourethanes

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Chinese Journal of Polymer Science 2024年第10期42卷 1435-1441,I0007页

作者： Bo Yang Hai-Jun Feng Tian-Tian Ni Xiao-Rui Zhou Tao xie Ning Zheng State Key Laboratory of Chemical engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China

The incorporation of dynamic covalent bonds into thermosets facilitates the reprocessing of polymer networks,thereby meeting the sustainable requirements for polymer ***,the mechanical properties of many materials often decline significantly upon reprocessing due to side reactions caused by harsh processing *** this work,we find that the aromatic dithiocarbamate bond can undergo dissociation under mild conditions without the need for a catalyst,enabling the efficient reprocessing of the corresponding *** a consequence,the mechanical properties of the polydithiourethane can be largely preserved after *** discovery of this dynamic chemistry is anticipated to broaden the potential for material design in dynamic covalent polymer networks.

关键词： Reprocessing Polydithiourethane Dynamic covalent bond

Electric-controlled pressure relief valve for enhanced safety in liquid-cooled lithium-ion battery packs

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Journal of Energy Chemistry 2024年第3期90卷 98-109,I0004页

作者： Yuhang Song Jidong hou Nawei Lyu Xinyuan Luo Jingxuan Ma Shuwen Chen Peihao Wu Xin Jiang Yang Jin Research Center of Grid Energy Storage and Battery Application School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001HenanChina

The liquid-cooled battery energy sto rage system(LCBESS) has gained significant attention due to its superior thermal management ***,liquid-cooled battery pack(LCBP) usually has a high sealing level above IP65,which can trap flammable and explosive gases from battery thermal runaway and cause *** poses serious safety risks and challenges for *** this study,we tested overcharged battery inside a commercial LCBP and found that the conventionally mechanical pressure relief valve(PRV) on the LCBP had a delayed response and low-pressure relief efficiency.A realistic 20-foot model of an energy storage cabin was constructed using the Flacs finite element simulation *** studies were conducted to evaluate the pressure relief efficiency and the influence on neighboring battery packs in case of internal explosions,considering different sizes and installation positions of the ***,a newly developed electric-controlled PRV integrated with battery fault detection is introduced,capable of starting within 50 ms of the battery safety valve ***,the PRV was integrated with the battery management system and changed the battery charging and discharging strategy after the PRV was *** tests confirmed the efficacy of this method in preventing *** paper addresses the safety concerns associated with LCBPs and proposes an effective solution for explosion relief.

关键词： Pressure relief valve Liquid-cooled battery pack Explosion Flacs

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橡胶轮转向架车辆动态曲线通过行为研究

铁道学报 2003年第3期25卷 40-44页

作者：王渊孙守光任尊松北方交通大学机械与电子控制工程学院北京100044

橡胶轮转向架在曲线通过方式上,与钢轮转向架有很大不同。在橡胶轮转向架稳态曲线通过行为研究的基础上,本文着重研究了橡胶轮转向架车辆的动态曲线通过行为。计算分析表明:橡胶轮转向架车辆在导轮横向力、轮重减载率和轮胎磨耗等方面... 详细信息

橡胶轮转向架在曲线通过方式上,与钢轮转向架有很大不同。在橡胶轮转向架稳态曲线通过行为研究的基础上,本文着重研究了橡胶轮转向架车辆的动态曲线通过行为。计算分析表明:橡胶轮转向架车辆在导轮横向力、轮重减载率和轮胎磨耗等方面具有优良的曲线通过性能。

关键词：橡胶轮转向架动力学曲线通过侧偏

Review on the Fabrication of Surface Functional Structures for Enhancing Bioactivity of Titanium and Titanium Alloy Implants

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Chinese Journal of mechanical engineering 2024年第4期37卷 23-49页

作者： Heng Tang Jiaxiang Xu Bin Guo Yansong xie Yalong Sun Yanjun Lu Yong Tang Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518000China school of mechanical and Power engineering Zhengzhou UniversityZhengzhou 450001China

Titanium and its alloys have been widely applied in many biomedical fields because of its excellent mechanical properties,corrosion resistance and good ***,problems such as rejection,shedding and infection will occur after titanium alloy implantation due to the low biological activity of titanium alloy *** structures with specific functions,which can enhance osseointegration and antibacterial properties,are fabricated on the surface of titanium implants to improve the biological activity between the titanium implants and human *** paper presents a comprehensive review of recent developments and applications of surface functional structure in titanium and titanium alloy *** applications of surface functional structure on different titanium and titanium alloy implants are introduced,and their manufacturing technologies are summarized and ***,the fabrication of various surface functional structures used for titanium and titanium alloy implants is reviewed and analyzed in ***,the challenges affecting the development of surface functional structures applied in titanium and titanium alloy implants are outlined,and recommendations for future research are presented.

关键词： Surface functional structure Titanium implant Manufacturing technology Bioactivity