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Robust model predictive control for discrete uncertain nonlinear systems with time-delay via fuzzy model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1723-1732页

作者： SU Cheng-li wang shu-qing National Laboratory of Industrial Control Technology Institute of Advanced Process Control Zhejiang University Hangzhou 310027 China

An extended robust model predictive control approach for input constrained discrete uncertain nonlinear systems with time-delay based on a class of uncertain T-S fuzzy models that satisfy sector bound condition is presented. In this approach, the minimization problem of the “worst-case” objective function is converted into the linear objective minimization problem in- volving linear matrix inequalities (LMIs) constraints. The state feedback control law is obtained by solving convex optimization of a set of LMIs. Sufficient condition for stability and a new upper bound on robust performance index are given for these kinds of uncertain fuzzy systems with state time-delay. Simulation results of CSTR process show that the proposed robust predictive control approach is effective and feasible.

关键词： Uncertain Takagi-Sugeno fuzzy model Time-delay Model predictive control (MPC) Linear matrix inequalities(LMIs) Robustness

Predictive control of a class of bilinear systems based on global off-line models

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 1984-1988页

作者： ZHANG Ri-dong wang shu-qing Institute of Advanced Process Control National Key Laboratory of Industrial Control Technology Zbejiang University Hangzhou 310027 China

A new multi-step adaptive predictive control algorithm for a class of bilinear systems is presented. The structure of the bilinear system is converted into a simple linear model by using nonlinear support vector machine (SVM) dynamic approximation with analytical control law derived. The method does not need on-line parameters estimation because the system’s internal model has been transformed into an off-line global model. Compared with other traditional methods, this control law reduces on-line parameter estimating burden. In addition, its overall linear behavior treating method allows an analytical control law available and avoids on-line nonlinear optimization. Simulation results are presented in the article to illustrate the efficiency of the method.

关键词： Bilinear systems Model predictive control (MPC) Adaptive control Support vector machine (SVM)

Compression Properties and Energy Absorption of A Novel Double Curved Beam Negative Stiffness Honeycomb Structures

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China Ocean Engineering 2024年第5期38卷 821-837页

作者： ZHENG Ze-peng wang shu-qing wang Xi-chen YUE Wen College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

This paper presents the design of a novel honeycomb structure with a double curved *** purpose of this design is to achieve vibration isolation for the main engine of an offshore platform and reduce impact *** analytical formula for the force-displacement relationship of the honeycomb single-cell structure is presented based on the modal superposition *** formula provides a theoretical basis for predicting the compression performance of honeycomb *** effects of structural geometric parameters,series and parallel connection methods on the mechanical and energy absorption properties are investigated through mathematical modeling and experimental ***,the study focuses on the vibration isolation and impact resistance performance of honeycomb *** results show that the designed honeycomb structure has good mechanical and energy absorption performance,and its energy absorption effect is related to the geometric parameters and series and parallel connection methods of the *** isolation efficiency of the honeycomb with 4 rows and 3 columns reaches 38%.The initial isolation frequency of the isolator is 11.7 Hz.

关键词： double curved beam compression properties energy absorption vibration isolation

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong wang shu-qing LIU Wen-cheng YE Xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Transferring CdTe Nanoparticles from Liquid Phase to Polyvinylpyrrolidone Nanofibers by Electrospinning and Detecting Its Photoluminescence Property

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Chemical Research in Chinese Universities 2008年第4期24卷 459-463页

作者： wang shu-gang YANG qing-biao BAI Jie SONG Yan ZHANG Chao-qun LI Yao-xian Department of Organic Chemistry College of Chemistry Jilin University Changchun 130021 P R. China

The major aim of this work was to synthesize thio-stabilized CdTe nanoparticles（NPs） in an aqueous solution, which was then enwrapped with cetyltrimethylammonium bromide（CTAB）, and finally transferred to the polyvinylpyrrolidone（PVP） matrix by electrospinning. The PVP nanofibers containing CdTe NPs were characterized by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）, to observe the morphology of the nanofibers and the distribution of CdTe NPs. The selective area electronic diffraction（SAED） pattern verified that CdTe NPs were cubic lattice. The photoluminescence（PL） spectrum indicated that CdTe NPs existed in an optical style in PVP nanofibers. Moreover, X-ray photoelectron spectra（XPS） revealed that thiol-stabilized CdTe NPs were enwrapped by CTAB, and PVP acted as a dispersant in the process of electrospinning.

关键词： CTAB Electrospinning Nanofiber Nanoparticle Photoluminescence

Experimental verifications on chemical carcinogenesis, a bifunctional alkvlation between DNA interstrands

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Chinese Science Bulletin 2000年第12期45卷 1075-1079页

作者： DAI Qianhuan, ZHANG qingrong, wang Lihui, PEI shu, wang qing &QUBoCenter for Chemistry and Bioengineering of Cancer, Beijing Polytechnic University, Beijing 100022, China Center for Chemistry and Bioengineering of Cancer Beijing Polytechnic University Beijing China

It is evidenced by the filter elution method that two carcinogenic aromatic hydrocarbons, benzo[a]pyrene and dibenzo[a,h]anthracene, two carcinogenic metal salts, beryllium chloride and cadmium chloride, four carcinogenic aromatic amines, 2-aminofluorene, p-naphthylamine, 4-aminobiphenyl and benzidine, can all induce DNA interstrand and DNA-protein cross-link in L12io culture. However, under the same condition, the corresponding non-carcinogenic compounds, including benzo[k]fluorancene, anthracene, magnesium chloride, zinc chloride, a-naphthylamine, 2-aminobiphenyl and m-toluidine, cannot produce any cross-link adducts. All these results are consistent with the di-region theory that carcinogens are bio-bifunctional alkylation agents. This method can also be used to discriminate carcinogens and non-carcinogens.

关键词： mechanism of chemical carcinogenesis di-region theory DNA interstrand cross-link aromatic amines poiycyclic aromatic hydrocarbons beryllium salt cadmium salt.

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高频增益未知的受扰非线性系统输出反馈控制

控制理论与应用 2006年第5期23卷 779-782页

作者：陈刚重庆大学自动化学院四川重庆400044

针对一类具有未知定常参数,包括未知高频增益的受扰非线性最小相位系统,给出了一种鲁棒自适应输出反馈控制策略．系统所受的干扰假设有界,但其界值是未知的．通过采用自适应策略来对其界值进行在线估计,控制算法并不需要高频增益符号的... 详细信息

针对一类具有未知定常参数,包括未知高频增益的受扰非线性最小相位系统,给出了一种鲁棒自适应输出反馈控制策略．系统所受的干扰假设有界,但其界值是未知的．通过采用自适应策略来对其界值进行在线估计,控制算法并不需要高频增益符号的先验知识．同时,系统中的非线性项并不要求满足增长性条件和匹配条件．算法使得估计参数量达到了最小,保证了闭环系统所有信号的有界性,同时使得跟踪误差渐近收敛于零．

关键词：非线性系统高频增益干扰输出反馈

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徐变自动增量分析方法及其实现

同济大学学报（自然科学版） 2000年第2期28卷 138-142页

作者：王书庆同济大学桥梁工程系上海200092

混凝土徐变收缩分析是桥梁结构分析中的基本问题 ,已有多种较成熟的计算方法 .从增量平衡方程出发 ,提出了适合利用现代计算机技术实现的时间自动增量徐变收缩分析方法 ,介绍了该方法的基本原理和特点 .并以正在研制开发的新一代桥梁集... 详细信息

混凝土徐变收缩分析是桥梁结构分析中的基本问题 ,已有多种较成熟的计算方法 .从增量平衡方程出发 ,提出了适合利用现代计算机技术实现的时间自动增量徐变收缩分析方法 ,介绍了该方法的基本原理和特点 .并以正在研制开发的新一代桥梁集成CAD系统 (BRCAD)为背景 ,简要介绍了徐变收缩分析方法在BRCAD系统中的实现 .最后给出了一个逐跨施工连续梁的徐变分析算例。

关键词：桥梁 CAD系统桥梁结构徐变收缩分析自动增量分析增量平衡方程等效弹性模量次内力变形

Malignant transformation of aneurysmal bone cysts： a case report

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Chinese Medical Journal 2009年第1期122卷 110-112页

作者： MEI Jiong GAO You-shui wang shu-qing CAI Xuan-song Department of Orthopedics Tongji Hospital Tongji University Shanghai 200065 China

An aneurysmal bone cyst is a non-neoplastic, .destructive and expansile lesion consisting of a＂blood-filled sponge＂ that is defined to represent a benign reactive vascularity. Szendroi et al suggested that the aneurysmal bone cyst corresponds to a haemodynamic disturbance that is primary or secondary venous malformation of the bones. The association with trauma including fracture has also been noted and 25%-71% of such patients have a history of trauma. Conventionally, malignant transformation of aneurysmal bone cysts is perceived as a rare occurrence except those induced by irradiation. Both malignant fibrous histiocytoma and osteosarcoma have been reported in the malignant transformation cases.

关键词： aneurysmal bone cyst prosthesis implantation malignant fibrous histiocytoma