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Advances in Manufacturing 2023年第4期11卷 587-600页

作者： da-wei zhang Wen-Long Gao-zhang Qi zhang Xi’an Key Laboratory of Intelligent Equipment and Control School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China

Distortion during the forging or machining processes of a blade causes problems in subsequent manufacturing. This paper proposes an alternative multipoint correction method integrated with blade measurement, determination of correcting parameters, and adjustment of the correcting die. An iterative algorithm for determining the correcting parameters is proposed. Measuring equipment combining a laser displacement sensor with multipoint flexible support is manufactured to measure the blade shape. Multipoint correcting equipment with an adaptive lower die and rapid adjustment is manufactured, and software is developed for data analysis and equipment control. The correction experiment for a rough-machined steam-turbine blade indicates that the correcting parameters can be determined after one modification based on numerical simulation, and that a rough blade that meets the allowance for finish machining can be obtained using the determined correction parameters.

关键词： Blade Surface measurement Numerical simulation Multipoint correction

Predictive sliding-mode control of networked high-order fully actuated systems under random deception attacks

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Science China(Information Sciences) 2023年第9期66卷 50-63页

作者： da-wei zhang Guo-Ping LIU Center for Control Theory and Guidance Technology Harbin Institute of Technology Center for Control Science and Technology Southern University of Science and Technology

This research addresses the output tracking of networked high-order fully actuated(NHOFA)systems under random deception attacks in the sensor to networked controller(SNC) and networked controller to actuator(NCA) communication channels, where a Bernoulli process represents the launching success rate of random deception attacks. A successful attack involves the output and control signals being tampered with by the injection of false data. Herein, a predictive sliding-mode control scheme is proposed to achieve the security tracking. In this scheme, a sliding-mode variable is introduced to defend the random deception attacks by enhancing the robustness of closed-loop systems. An incremental HOFA(IHOFA) prediction model is developed using a Diophantine equation as an alternative to the traditional reduced-order prediction model. Through this IHOFA prediction model, the multistep ahead predictions of the sliding-mode variable are constructed to optimize the tracking performance and defense of random deception attacks. By utilizing the Lyapunov function and linear matrix inequality(LMI) approach, a sufficient and necessary condition is proposed to ensure stability and high tracking performance of closed-loop NHOFA systems. Herein, an experiment on the tracking control of an air-bearing spacecraft(ABS) simulator is performed to demonstrate the effectiveness and practicability of the predictive sliding-mode control scheme.

关键词： NHOFA systems random deception attacks predictive sliding-mode control stability and tracking performance tracking control of ABS simulator

Effect of Carboxymethyl Cellulose(CMC) Functionalization on Dispersion, Mechanical, and Corrosion Properties of CNT/Epoxy Nanocomposites

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Chinese Journal of Polymer Science 2023年第8期41卷 1277-1286,I0010页

作者： da-wei zhang Leonard Chia Ying Huang Department of Civil Construction and Environmental EngineeringNorth Dakota State UniversityFargo 58108USA

Carbon nanotube(CNT)/epoxy nanocomposites have a great potential of possessing many advanced ***,the homogenization of CNT dispersion is still a great challenge in the research field of *** study applied a novel dispersion agent,carboxymethyl cellulose(CMC),to functionalize CNTs and improve CNT dispersion in *** effectiveness of the CMC functionalization was compared with mechanical mixing and a commonly used surfactant,sodium dodecylbenzene sulfonate(Na DDBS),regarding dispersion,mechanical and corrosion properties of CNT/epoxy nanocomposites with three different CNT concentrations(0.1%,0.3%and 0.5%).The experimental results of Raman spectroscopy,particle size analysis and transmission electron microscopy showed that CMC functionalized CNTs reduced CNT cluster sizes more efficiently than Na DDBS functionalized and mechanically mixed CNTs,indicating a better CNT *** peak particle size of CMC functionalized CNTs reduced as much as 54%(0.1%CNT concentration)and 16%(0.3%CNT concentration),compared to mechanical mixed and Na DDBS functionalized *** of the better dispersion,it was found by compressive tests that CNT/epoxy nanocomposites with CMC functionalization resulted in 189%and 66%higher compressive strength,224%and 50%higher modulus of elasticity than those with mechanical mixing and Na DDBS functionalization respectively(0.1%CNT cencentration).In addition,electrochemical corrosion tests also showed that CNT/epoxy nanocomposites with CMC functionalization achieved lowest corrosion rate(0.214 mpy),the highest corrosion resistance(201.031Ω·cm^(2)),and the lowest porosity density(0.011%).

关键词： CNT/epoxy composites Carboxymethyl cellulose Dispersion Mechanical properties Corrosion properties

Disturbance Observer-Based Predictive Tracking Control of Uncertain HOFA Cyber-Physical Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1711-1713页

作者： da-wei zhang Guo-Ping Liu IEEE the Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

Dear Editor,In this letter,an output tracking control problem of uncertain cyber-physical systems(CPSs)is considered in the perspective of high-order fully actuated(HOFA)system theory,where a lumped disturbance is use... 详细信息

关键词： Observer Uncertain letter

Surf4,cargo trafficking,lipid metabolism,and therapeutic implications

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Journal of Molecular Cell Biology 2022年第9期14卷 3-13页

作者： Yishi Shen Hong-Mei Gu Shucun Qin da-wei zhang Group on the Molecular and Cell Biology of Lipids and Department of Pediatrics Faculty of Medicine and DentistryUniversity of AlbertaEdmonton ABT6R2G3Canada Institute of Atherosclerosis in Shandong First Medical University(Shandong Academy of Medical Sciences) Taian 271016China

Surfeit 4 is a polytopic transmembrane protein that primarily resides in the endoplasmic reticulum(ER)*** is ubiquitously expressed and functions as a cargo receptor,mediating cargo transport from the ER to the Golgi apparatus via the canonical coat protein complex Il(CoPll)-coated vesicles or specific *** also participates in ER-Golgi protein trafficking through a tubular ***,it facilitates retrograde transportation of cargos from the Golgi apparatus to the ER through Coplcoated ***4 can selectively mediate export of diverse cargos,such as PCSK9 very low-density lipoprotein(VLDL),progranulin,α1-antitrypsin,STING,proinsulin,and *** has been implicated in facilitating VLDL secretion,promoting cell proliferation and migration,and increasing replication of positive-strand RNA ***,Surf4 plays a crucial role in various physiological and pathophysiological processes and emerges as a promising therapeutic ***,the molecular mechanisms by which Surf4 selectively sorts diverse cargos for ER-Golgi protein trafficking remain ***,we summarize the most recent advances in Surf4,focusing on its role in lipid metabolism.

关键词： VLDL secretion cargo receptor PCSK9 lipid metabolism atherosclerosis trafficking

Hypercholesterolemia,low density lipoprotein receptor and proprotein convertase subtilisin/kexin-type 9

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The Journal of Biomedical Research 2015年第5期29卷 356-361页

作者： Hong-mei Gu da-wei zhang Departments of Pediatrics and Biochemistry Group on the Molecular and Cell Biology of LipidsUniversity of Alberta

Atherosclerotic cardiovascular disease is the main cause of mortality and morbidity in the world. Plasma levels of low density lipoprotein cholesterol （LDL-C） are positively correlated with the risk of atherosclerosis. High plasma LDL concentrations in patients with hypercholesterolemia lead to build-up of LDL in the inner walls of the arteries, which becomes oxidized and promotes the formation of foam cells, consequently initiating atherosclerosis. Plasma LDL is mainly cleared through the LDL receptor （LDLR） pathway. Mutations in the LDLR cause familiar hyperch- olesterolemia and increase the risk of premature coronary heart disease. The expression of LDLR is regulated at the transcriptional level via the sterol regulatory element binding protein 2 （SREBP-2） and at the posttranslational levels mainly through proprotein convertase subtilisin/kexin-type 9 （PCSK9） and inducible degrader of the LDLR （IDOL）. In this review, we summarize the latest advances in the studies of PCSK9.

关键词： hypercholesterolemia low density lipoprotein receptor statin atherosclerosis proprotein convertasesubtilisin/kexin -type 9

Corrosion behavior and characteristics of the product film of API X100 steel in acidic simulated soil solution

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 176-183页

作者： Cui-wei Du Tian-liang Zhao Zhi-yong Liu Xiao-gang Li da-wei zhang Corrosion and Protection Center University of Science and Technology Beijing Key Laboratory of Chinese Ministry of Education for Corrosion and Prevention University of Science and Technology Beijing

The short-term corrosion behavior of API X100 steel in an acidic simulated soil was investigated by electrochemical measurements and soaking experiments,followed by corrosion morphology observations and X-ray photoelectron spectroscopy *** results show that X100 steel exhibits an obvious pitting susceptibility in an acidic soil *** nucleate after approximately 10 h of *** with the nucleation and growth of the pits,the charge-transfer resistance and open-circuit potential first increase sharply,then decrease slowly,and eventually reach a steady *** maxima of the charge-transfer resistance and open-circuit potential are attained at approximately 10 *** evolution of the electrochemical process is confirmed by the analysis of the product *** product film exhibits a porous and loose structure and could not protect the substrate *** product film is primarily composed of ferrous carbonate and ferrous hydroxide（Fe（OH）2）.The concentration of Fe（OH）2 in the product film increases from the inside to the outside layer.

关键词： oil pipelines steel corrosion acidic environment pitting corrosion corrosion films

Closed-Form Modeling and Analysis of an XY Flexure-Based Nano-Manipulator

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 176-186页

作者： Yan-Ding Qin Xin Zhao Bijan Shirinzadeh Yan-Ling Tian da-wei zhang Institute of Robotics and Automatic Information System (Tianjin Key Laboratory of Intelligent Robotics) Nankai University Robotics and Mechatronics Research Laboratory Department of Mechanical and Aerospace Engineering Monash University School of Mechanical Engineering Tianjin University

Flexure-based mechanisms are widely utilized in nano manipulations. The closed-form statics and dynamics modeling is difficult due to the complex topologies, the inevitable compliance of levers, the Hertzian contact interface, etc. This paper presents the closed-form modeling of an XY nano-manipulator consisting of statically indeterminate symmetric(SIS) structures using leaf and circular flexure hinges. Theoretical analysis reveals that the lever’s compliance, the contact stiffness, and the load mass have significant influence on the static and dynamic performances of the *** are conducted to verify the effectiveness of the established models. If no piezoelectric actuator(PEA) is installed, the influence of the contact stiffness can be eliminated. Experimental results show that the estimation error on the output stiffness and first natural frequency can reach 2% and 1.7%, respectively. If PEAs are installed, the contact stiffness shows up in the models. As no effective method is currently available to measure or estimate the contact stiffness, it is impossible to precisely estimate the performance of the overall system. In this case, the established closed-form models can be utilized to calculate the bounds of the performance. The established closed-form models are widely applicable in the design and optimization of planar flexure-based mechanisms.

关键词： Flexure-based mechanism Statically indeterminate structure Dynamics Lever mechanism Piezoelectric actuator

DNA cleavage promoted by diethylenetriaminepentaacetic acid (DTPA) derivatives

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Chinese Chemical Letters 2009年第9期20卷 1107-1110页

作者： Zhong wei Yao Jun Xu da wei zhang Hong Hui Lin Chuan Qin Xia College of Chemistry Sichuan University Chengdu 610064. China School of Life Science Sichuan University Chengdu 610064 China

DTPA and its two derivatives were synthesized and used as catalysts in DNA cleavage. Under physiological conditions, a series of experiments have been done. The effects of DNA cleavage with three ligands were studied under different concentrations, cleavage time, and pH values. The results strongly suggested that the plasrnid DNA （pUC 19） can be cleaved efficiently by CITC- DTPA. For the cleavage reaction catalyzed by CITC-DTPA, Form I DNA could convert to Form II mostly, and the DNA-cleavage mechanism involved an oxidative pathway. 2009 Chuan Qin Xia. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： TPA Derivatives DNA cleavage Cleavage mechanism

Flash flood hazard mapping: A pilot case study in Xiapu River Basin, China

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Water Science and Engineering 2015年第3期8卷 195-204页

作者： da-wei zhang Jin Quan Hong-bin zhang Fan Wang Hong Wang Xiao-yan He China Institute of Water Resources and Hydropower Research Research Center on Flood and Drought Disaster Reduction Ministry of Water Resources

Flash flood hazard mapping is a supporting component of non-structural measures for flash flood prevention. Pilot case studies are necessary to develop more practicable methods for the technical support systems of flash flood hazard mapping. In this study, the headwater catchment of the Xiapu River Basin in central China was selected as a pilot study area for flash flood hazard mapping. A conceptual distributed hydrological model was developed for flood calculation based on the framework of the Xinanjiang model, which is widely used in humid and semi-humid regions in China. The developed model employs the geomorphological unit hydrograph method, which is extremely valuable when simulating the overland flow process in ungauged catchments, as compared with the original Xinanjiang model. The model was tested in the pilot study area, and the results agree with the measured data on the whole. After calibration and validation, the model is shown to be a useful tool for flash flood calculation. A practicable method for flash flood hazard mapping using the calculated peak discharge and digital elevation model data was presented, and three levels of flood hazards were classified. The resulting flash flood hazard maps indicate that the method successfully predicts the spatial distribution of flash flood hazards, and it can meet the current requirements in China.

关键词： Flash flood hazard mapping Conceptual distributed hydrological model Xinanjiang model Geomorphological unit hydrograph Xiapu River Basin