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Optimized design and performance evaluation of an electric cup-chain potato metering device

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International Journal of Agricultural and Biological Engineering 2017年第2期10卷 36-43页

作者： Niu Kang Fang Xianfa Liu Yangchun Lü Chengxu Yuan Yanwei College of Engineering China Agricultural UniversityBeijing 100083China State Key Laboratory of Soil-Plant-Machine system Technology Chinese Academy of Agricultural Mechanization SciencesBeijing 100083China

The cup-chain metering device is commonly used in potato planters despite its problems of missing-seeding,double-seeding and ground wheel sliding.A mechanical-electrical design was developed for planters to resolve these problems.A regression experiment was conducted with three factors(chain speed,chain tightening distance and cup tilting)and two indicators(missing-seeding rate and double-seeding rate).Based on the results of regression experiment,a numerical regression model was built and a multi-objective optimization method was used to get an optimal ***,the optimized device was tested in the *** device design presents a tilting seed cup with a guard plate and an electric control *** laboratory test showed that the missing-seeding rate increased with the chain *** initially decreases and then increases with the chain tightening distance and cup tilting *** double-seeding rate declines with chain *** increases initially and declines afterward with the chain tightening *** optimization resulted in a missing-seeding rate of 4.39%and a double-seeding rate of 8.78%under the parameters of 0.32 m/s seeding speed,0.94×10-3 m tightening distance,and 12.5°cup tilting *** field test demonstrated that electric control instead of ground wheel-driven chain enables fast seeding and precise intra-row seeding distance.

关键词： potato planter cup-chain metering device multi-objective optimization regression method

Adaptive tracking H-infinity control for switched nonlinear systems with unknown control gain sign

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控制理论与应用（英文版） 2011年第4期9卷 579-583页

作者： LeiYU ShuminFEI HairongZHU XunLI School of mechanical and Electrical Engineering Soochow UniversitySuzhou Jiangsu 215021China SchoolofAutomation SoutheastUni＇JersityNanjingJiangsu210096China

This paper addresses the adaptive tracking control scheme for switched nonlinear systems with unknown control gain sign. The approach relaxes the hypothesis that the upper bound of function control gain is known constant and the bounds of external disturbance and approximation errors of neural＇networks are known. RBF neural networks （NNs） are used to approximate unknown functions and an H-infinity controller is introduced to enhance robustness. The adaptive updating laws and the admissible switching signals have been derived from switched multiple Lyapunov function method. It＇s proved that the resulting closed loop system is asymptotically Lyapunov stable such that the output tracking error performance and H-infinity disturbance attenuation level are well obtained. Finally, a simulation example of Forced Duffing systems is given to illustrate the effectiveness of the proposed control scheme and improve significantly the transient performance.

关键词： RBF neural networks Adaptive tracking control H-infinity control Tracking error performance

Interval Fault Tree Analysis of Excavator VariableFrequency Speed Control system

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Journal of Donghua University(English Edition) 2014年第6期31卷 763-765,769页

作者：王晓明李爱峰张永明米金华黄洪钟 Taiyuan Heavy Industry Co. Ltd. School of mechanical Electronic and Industrial Engineering University of Electronic Science and Technology of China

In consideration of the uncertainty of basic events failure rate and lack of probability statistical information in fault tree analysis( FTA) of excavator variable-frequency speed control system, the interval theory was employed and combined with conventional FTA method. The basic events failure probabilities were described by interval numbers,and the interval operators of logical gates in FTA were deduced based on interval theory. Finally,the reliability assessment of excavator variable-frequency speed control system was done by interval FTA method. The result shows that the interval FTA method is suitable for the complex system with insufficient failure data.

关键词： fault tree analysis(FTA) interval theory interval probability excavator electrical sytem

Reliability Allocation of Large Mining Excavator Electrical system Based on the Entropy Method with Failure and Maintenance Data

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Journal of Donghua University(English Edition) 2014年第6期31卷 779-781页

作者：胡天松黄洪钟王晓明李光高素荷 School of mechanical Electronic and Industrial Engineering University of Electronic Science and Technology of China Taiyuan Heavy Industry Co. Ltd.

In the design of large mining excavator electrical system,a practical reliability allocation method was introduced to allocate system level reliability requirements into subsystem and component levels. During the reliability allocation process,factors from the fault and maintenance data were only considered in reliability allocation scheme. It could avoid the disturbance from expert experiences. The entropy method was also used to obtain weights of reliability allocation indexes of large mining excavators considering different factors. Then the failure rate allocation of subsystems and components could be completed.

关键词： reliability allocation large mining excavators the entropy method

Reversal of the diabetic bone signature with anabolic therapies in mice

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Bone research 2023年第2期11卷 328-339页

作者： Silvia Marino Nisreen Akel Shenyang Li Meloney Cregor Meghan Jones Betiana Perez Gaston Troncoso Jomeeka Meeks Scott Stewart Amy YSato Intawat Nookaew Teresita Bellido Department of Physiology and Cell Biology University of Arkansas for Medical SciencesLittle RockARUSA Central Arkansas Veterans Healthcare system John L.Mc Clellan Little RockLittle RockARUSA Department of Biostatistics University of Arkansas for Medical SciencesLittle RockARUSA Department of Biomedical Informatics University of Arkansas for Medical SciencesLittle RockARUSA Winthrop P.Rockefeller Cancer Institute University of Arkansas for Medical SciencesLittleRockARUSA

The mechanisms underlying the bone disease induced by diabetes are complex and not fully understood;and antiresorptive agents,the current standard of care,do not restore the weakened bone ***,we reveal the diabetic bone signature in mice at the tissue,cell,and transcriptome levels and demonstrate that three FDA-approved bone-anabolic agents correct *** decreased bone mineral density(BMD)and bone formation,damaged microarchitecture,increased porosity of cortical bone,and compromised bone ***(PTH),abaloparatide(ABL),and romosozumab/anti-sclerostin antibody(Scl-Ab)all restored BMD and corrected the deteriorated bone ***,PTH and more potently ABL induced similar responses at the tissue and gene signature levels,increasing both formation and resorption with positive balance towards bone *** contrast,Scl-Ab increased formation but decreased *** agents restored bone architecture,corrected cortical porosity,and improved mechanical properties of diabetic bone;and ABL and Scl-Ab increased toughness,a fracture resistance ***,all agents increased bone strength over the healthy controls even in the presence of severe *** findings demonstrate the therapeutic value of bone anabolic agents to treat diabetes-induced bone disease and suggest the need for revisiting the approaches for the treatment of bone fragility in diabetes.

关键词： signature porosity corrected

Improved LQG Benchmark Based Control Performance Monitoring for Multivariable systems 25th

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Improved LQG Benchmark Based Control Performance Monitoring ...

Fabrication of micro/nano-structures by electrohydrodynamic jet technique

第25届中国控制与决策会议

作者： Zhang Deng-feng Bao Bing-rui Lu Bao-chun Wang Zhi-quan Institute of Lianyungang Nanjing University of Science and Technology School of mechanical Engineering Nanjing University of Science and Technology

ISBN: (纸本)9781467355339

By subspace identification technique, this article investigates the problem of control variance performance monitoring for multivariable systems. Based on LQG benchmark, an improved strategy is developed to overcome the deficiency of the conventional LQG benchmark based methods in practical applications. The multivariable system is first decomposed into multiple multi-input single-output （MISO） subsystems. Then the LQG benchmark is respectively obtained for each subsystem and the corresponding variance performance assessment indicator is yielded. The performance monitoring result of the overall system can finally be derived by weighting to each subsystem’s assessing indicator. Simulation example illustrated the validity of the proposed method.

关键词： Control Performance Monitoring and Assessment Multivariable systems Subspace Identification LQG Benchmark

来源： cnki会议评论

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Frontiers of mechanical Engineering 2017年第4期12卷 477-489页

作者： Dazhi WANG Xiaojun ZHAO Yigao LIN Tongqun REN Junsheng LIANG Chong LIU Liding WANG Key Laboratory for Micro/Nano Technology and system of LiaoningProvince Dalian University of Technology Dalian 116024 China Key Laboratory for Precision and Non-traditional MachiningTechnology of the Ministry of Education Dalian University ofTechnology Dalian 116024 China

Electrohydrodynamicjet （E-Jet） is an approach to the fabrication of micro/nano-structures by the use of electrical forces. In this process, the liquid is subjected to electrical and mechanical forces to form a liquid jet, which is further disintegrated into droplets. The major advantage of the E-Jet technique is that the sizes of the jet formed can be at the nanoscale far smaller than the nozzle size, which can realize high printing resolution with less risk of nozzle blockage. The E-Jet technique, which mainly includes E-Jet deposition and E-Jet printing, has a wide range of applications in the fabrication ofmicro/nano-structures for micro/nano-electromechanical system devices. This tech- nique is also considered a micro/nano-fabrication method with a great potential for commercial use. This study mainly reviews the E-Jet deposition/printing fundamentals, fabrication process, and applications.

关键词： electrohydrodynamic jet deposition electro-hydrodynamic jet printing micro/nano-structures film

Functional Tough Hydrogels: Design, Processing, and Biomedical Applications

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Accounts of Materials research 2023年第2期4卷 101-114页

作者： Xiao Kuang Mehmet Onur Arıcan Tao Zhou Xuanhe Zhao Yu Shrike Zhang division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolCambridgeMassachusetts 02139United States Department of Polymer Science and Technology Kocaeli University41001 KocaeliTurkey

Hydrogels are high-water-content soft materials with widely tunable physicochemical properties,resembling soft *** progress in engineering hydrogels with good biocompatibility,suitable bioactivities,and controlled geometries has made them promising candidates for broad ***,conventional hydrogels usually suffer from weak mechanical properties,limiting their use in biomedical settings involving load-bearing and persistent mechanical *** by the extreme mechanical properties and multiscale hierarchical structures of biological tissues,mechanically robust tough hydrogels have been *** robust mechanical properties and other desired performance characteristics in functional tough hydrogels expands their opportunities in biomedical *** Account seeks to guide the readership regarding the recent progress in functional tough hydrogels with a focus on molecular/structural design and novel fabrications,particularly surrounding the works reported by our ***,functional tough hydrogels for multiple biomedical applications are discussed,highlighting the underlying mechanisms governing their relevant *** begin by introducing the definition,measurements,and design principles of tough hydrogels and hydrogel adhesives in terms of soft materials *** molecular and structural engineering approaches by building mechanical dissipation into stretchable hydrogels to realize stress homogenization or energy dissipation are exploited to fabricate tough *** engineering-based network architecture design of homogeneous hydrogels and structural engineering-based design of heterogeneous hydrogels are *** conventional energy-dissipation-based tough hydrogels are reinforced by the sacrificial bonds or components,leading to a substantial toughness reduction in subsequent loading *** this end,new molecular designs,including highly entangled hydrogels and sl

关键词： Hydrogel bonds dealing

Dynamic Simulations of Nonlinear Multi-Domain systems Based on Genetic Programming and Bond Graphs

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Tsinghua Science and Technology 2009年第5期14卷 612-616页

作者：狄文辉孙波徐立新 Department of Computer Science and Technology Henan Mechanical and Electrical Engineering College Department of Control Science and Engineering Huazhong University of Science and Technology

A dynamic simulation method for non-linear systems based on genetic programming （GP） and bond graphs （BG） was developed to improve the design of nonlinear multi-domain energy conversion systems. The genetic operators enable the embryo bond graph to evolve towards the target graph according to the fitness function. Better simulation requires analysis of the optimization of the eigenvalue and the filter circuit evolution. The open topological design and optimized convergence for the operation, but also the design of nonlinear multi-domain systems. space search ability of this method not only gives a more reduces the generation time for the new circuit graph for

关键词： genetic programming (GP) bond graph (BG) evolutionary computation system simulation