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study on active vibration control technique based on cantilever beam

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Study on active vibration control technique based on cantile...

2010 International Conference on Computer,Mechatronics, Control and Electronic engineering (CMCE 2010)

作者： Dong Jingshi1, Guo Kang1, Zheng Wei1, shen Chuanliang1,Cheng Guangming1 1.college of mechanical science and engineering 2.college of Automotive engineering Jilin university Changchun,China Ding Ji department of mechanical engineering Aviation university of Air Force Changchun,China

In order to solve the contradiction between lightweight and noise of a vibrating cantilever beam, active control actuated by piezoelectric ceramics is presented in this study. The dynamic model of the cantilever beam is established by finite element method (FEM). The piezoelectric actuator excited by control signal is bonded near the fixed end of the cantilever beam to suppress the beam's first vibration mode. The control signal is collected by a sensor and processed by the quadratic optimal control theory. Experiment results show that the amplitude of the active controlled cantilever beam is reduced to 48.2% than the uncontrolled one under constant external excitation.

关键词： active control cantilever beam piezoelectric actuator finite element method LabVIEW

Fabrication of gelatin-hyaluronic acid hybrid scaffolds with tunable porous structures for soft tissue engineering

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Fabrication of gelatin-hyaluronic acid hybrid scaffolds with...

生物材料与再生医学的现状与未来——2010年第十届上海地区医用生物材料研讨会

作者： Fan Zhang~2,Chuanglong He~(1,2,3*),Lijun Cao~2,Wei Feng~2,Hongsheng Wang~2,Xiumei Mo~(1,2,3) Jinwu Wang~(4*) 1 Key Laboratory of Textile science & Technology,Ministry of Education,Donghua university,shanghai,P.R. China 201620 2 college of Chemistry,Chemical engineering and Biotechnology,Donghua university,shanghai,P.R.China 201620 3 state Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua university, shanghai,P.R.China 201620 4 department of Orthopaedic surgery,Ninth People’s Hospital,shanghai Jiao Tong university school of Medicine, shanghai,P.R.China 200011

The development of three -dimensional(3 -D) scaffolds with highly open porous structure is one of the most important issues in tissue *** this study,3-D macroporous gelatin/hyaluronic acid(GE/HA) hybrid scaffolds with varying porous morphology were prepared by freeze -drying their blending solutions and subsequent chemical crosslinking by using 1 -Ethyl -3 -(3 -dimethylaminopropyl) carbodiimide hydrochloride (EDC).The resulting scaffolds were characterized by scanning electron microscopy(sEM) and Fourier transform infrared spectroscopy(FTIR).Their swelling,in vitro degradation properties and compressive strength were also *** evaluate in vitro cytocompatibility of scaffolds,mouse L929 fibroblasts were seeded onto the scaffolds for cell morphology and cell viability *** was found that the porous structure of scaffolds can be tailored by varying the ratios of gelatin to HA,both the swelling ratios and degradation rate increased with the increase of HA content in hybrid scaffolds,and crosslinking the scaffolds with EDC improved the degradation resistance of the scaffold in culture media and increased the mechanical strength of *** in vitro results revealed that the prepared scaffolds do not induce cytotoxic effects and suitable for cell growth,especially in the case of scaffolds with higher gelatin *** combined results of the physicochemical and biological studies suggested that the developed GE/HA hybrid scaffolds exhibit good potential and biocompatibility for soft tissue engineering applications.

关键词： Gelatin Hyaluronic acid Porous scaffold Freeze-drying Tissue engineering

Reactive Power Optimization for Distribution systems Based on Dual Population Ant Colony Optimization

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Reactive Power Optimization for Distribution Systems Based o...

第二十七届中国控制会议

作者： Guo Lirui 1,Huo Limin 1,Zhang Liguo 2,Liu Weina 1,Hu Jie 1 1.department of mechanical and Electronic engineering,Agricultural university of Hebei,Baoding,071001,P.R.China 2.college of Information science and Technology,Agricultural university of Hebei,Baoding,071001,P.R.China

The Dual Population Ant Colony Optimization（DPACO） was tried to be applied to Power system Dynamic Reactive Power *** installation positions of capacitors were taken as obstacles,the capacities of capacitors installed were taken as the paths through which the ants climb over the obstacles and the mathematical models of the reactive power planning under the multiple load state were *** running process,the pheromone was adjusted according to the ant’s search results and the principle of pheromone modification and the convergence speed was *** the same time,the Dual Population Ant Colony Optimization（DPACO） avoided trapping in local optimum and increased the precision of Reactive Power Opti-mization for doing well in global *** optimization,the voltage quality was enhanced obviously and compre-hensive fees decrease *** running results show that Dual Population Ant Colony Optimization（DPACO） applied to Power system Dynamic Reactive Power Optimization is feasible and effective.

关键词： Reactive Power Optimization Dual Population Ant Colony Optimization (DPACO) Distribution system Opti-mization Algorithm

A Novel Approach to Breast Tumor Detection: Enhanced speckle Reduction and Hybrid Classification in Ultrasound Imaging

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Computers, Materials & Continua 2024年第5期79卷 1875-1901页

作者： K.Umapathi s.shobana Anand Nayyar Judith Justin R.Vanithamani Miguel Villagómez Galindo Mushtaq Ahmad Ansari Hitesh Panchal department of Biomedical engineering KIT-Kalaignarkarunanidhi Institute of TechnologyCoimbatore641402India Graduate school Faculty of Information TechnologyDuy Tan UniversityDa Nang550000Viet Nam department of Biomedical and Instrumentation engineering Avinashilingam Institute for Home Science and Higher Education forWomenCoimbatore641043India UniversidadMichoacana de sanNicolás de HidalgoAvenida Francisco J.Múgica s/N Ciudad Universitaria MoreliaCP58030Mexico department of Pharmacology and Toxicology College of PharmacyKing Saud UniversityRiyadh11451Saudi Arabia department of mechanical engineering Gujarat Technological UniveristyNigam NagarChandkhedaAhmedabadGujarat382424India

Breast cancer detection heavily relies on medical imaging, particularly ultrasound, for early diagnosis and effectivetreatment. This research addresses the challenges associated with computer-aided diagnosis (CAD) of breastcancer fromultrasound images. The primary challenge is accurately distinguishing between malignant and benigntumors, complicated by factors such as speckle noise, variable image quality, and the need for precise segmentationand classification. The main objective of the research paper is to develop an advanced methodology for breastultrasound image classification, focusing on speckle noise reduction, precise segmentation, feature extraction, andmachine learning-based classification. A unique approach is introduced that combines Enhanced speckle ReducedAnisotropic Diffusion (sRAD) filters for speckle noise reduction, U-NET-based segmentation, Genetic Algorithm(GA)-based feature selection, and Random Forest and Bagging Tree classifiers, resulting in a novel and efficientmodel. To test and validate the hybrid model, rigorous experimentations were performed and results state thatthe proposed hybrid model achieved accuracy rate of 99.9%, outperforming other existing techniques, and alsosignificantly reducing computational time. This enhanced accuracy, along with improved sensitivity and specificity,makes the proposed hybrid model a valuable addition to CAD systems in breast cancer diagnosis, ultimatelyenhancing diagnostic accuracy in clinical applications.

关键词： Ultrasound images breast cancer tumor classification segmentation deep learning lesion detection

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基因芯片纳米挠度和表面应力的解析预测

力学季刊 2010年第1期31卷 113-117页

作者：李晶晶谭邹卿张能辉上海市应用数学和力学研究所上海200072 上海大学理学院力学系上海200444

本文利用能量法解析分析了无标记生物检测中基因芯片的纳米力学行为。首先,考虑微悬臂梁机械能和基因层静电能、水合能和构型熵,建立了基因芯片能量模型,并采用泰勒级数展开法,获得了能量势的一阶近似式。其次,利用能量最小原理,得到了... 详细信息

本文利用能量法解析分析了无标记生物检测中基因芯片的纳米力学行为。首先,考虑微悬臂梁机械能和基因层静电能、水合能和构型熵,建立了基因芯片能量模型,并采用泰勒级数展开法,获得了能量势的一阶近似式。其次,利用能量最小原理,得到了芯片稳态弯曲的曲率半径、纳米挠度和表面应力的解析表达式,从而克服了求解多极值能量泛函数值解的困难。最后,预测了DNA的链长和种植密度对芯片纳米力学行为的影响,同时将表面应力的解析预测结果与有关实验数据进行了比较,证明了本文方法的可靠性。

关键词：基因芯片生物能纳米力学解析法表面应力

H∞ Control for Continuous-time T-s Fuzzy systems Using Fuzzy Lyapunov Functions:A LMI Approach

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H∞ Control for Continuous-time T-S Fuzzy Systems Using Fuzz...

2010 Chinese Control and Decision Conference

作者： Xiao-Heng Chang~(1,3),Liang Hong~2,Yi-Fu Feng~3 1.college of Information science and engineering,Bohai university,Jinzhou,121003 2.school of mechanical Electronic and Information Engineer,China university of Mining and Technology,Beijing,100083 3.school of Information science and engineering,Northeastern university,shenyang,110004

The problems of relaxed stability conditions and state feedback Hcontroller designs are studied for continuous-time T-s fuzzy systems using fuzzy Lyapunov functions approach.A new stability conditions are obtained by relaxing the stability conditions derived in previous papers,and a sufficient LMI conditions which guarantee the existence of the state feedback Hcontroller for T-s fuzzy systems is *** the solving approach for BLMI is studied based on convex optimization *** the effectiveness of the proposed approach is shown through two numerical examples.

关键词： Continuous-time T-s fuzzy systems Fuzzy Lyapunov functions H∞ LMI

Design of new intelligent street light control system

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Design of new intelligent street light control system

2009年中国智能自动化会议

作者： WU Yue~(1,2),sHI Changhong~3,LI Yan~1,ZHANG Wen-dong~1 (1 National Key Laboratory for Electronic Measurement Technology, North university of China,Taiyuan 030051,China 2 The mechanical and Electronic engineering college, North university of China,Taiyuan 030051,China 3 The Quartermaster Institute of the General Logistics department of the P.L.A, Beijing 100010,China)

In China,the methods of time-control,optical-control and time-optical-control are in common used to control street lamp,particularly in small and medium-sized cities. But the precision is bad,and the result of work is also *** main reason is the backward lighting control and administrative method. Through many kinds of sensor combination sense environment’s change,the multi-sensor exhibition can combinatory logically control the new intelligent street light controller *** based on the degree of illumination control fixed time,in the automatic foundation fixed time,according to the multi-sensing exhibition survey data’s special combination change,to control the street light nimbly;the system can also realize the automatic timing control,by the preinstall time to control street light switch,ultimately, to control the street light timed;simultaneously can also realize the automatic sunshine control,which may act according to the actual determination the sunlight degree of illumination and the degree of illumination control criterion,automatic control street light. On the basis of the merits both the regular control and the optical control,a new street smart controller is designed,with dual functions both timing control and automatic photoelectric *** allows street lamps automatic lit in the evening,lighting the road for a few hours(adjustable time).After 0:00,when few vehicles or pedestrians go past,it turn off *** terminal controller has wake-up *** the street light turn out automatically,when the vehicles or pedestrians are going through,street light will be waken up by terminal controller,When the vehicles or pedestrians past,the light *** of new intelligent street light control system does not only achieve energy-saving power but also extend the service life of lighting ***,it is controllable,ease of *** the same time,it is helpful to highlight the festive and other characteristics,an

关键词： Public street lighting intelligent controller

Finite Element Analysis and Experiment Research on surface Residual stress of Ceramics Grinding

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Finite Element Analysis and Experiment Research on Surface R...

第十届国际制造工程与管理会议

作者： TIAN Xin-H, YU Ai-bing, LIN Bin(1. department of Materials, Armored Force engineering college, Beijing 100072, China 2. Tianjin university, Tianjin 300072, China)

＜正＞ The theoretical model of residual stress of ceramics grinding has been established applying thermal elastoplastic mechanics theory. While grinding at the course of grinding wheel moved along workpiece surface the distributing regulation of residual stress can be simplified into thermal elastioplastic mechanical issue, under the action of the both moving centralized force and heat source. Calculating and evaluating of surface residual stress using current procedure of finite element analysis which has been reformed is successful. Comparing with X-ray diffraction experiment method, satisfactory precision has been acquired. The results of experiment show the changing regularity of residual stresses after grinding A12O3 using diamond wheel, on condition that alter grinding parameters. The values of residual compress stress are taken place changing at key certain critical point on their figure as follow: When grinding depth ap is lower than 50 μm, the residual compress stresses are increased with grinding depth increasing, on the contrary as ap＞50 μm. At Vw＜8 m/min, the residual compress stresses increased rapidly with feed speed of work-piece increasing, on the contrary at Vw＞8 m/min. When Vs＜25 m/s the residual stress increased with wheel speed increasing and keep stable in value at Vs＞25 m/s. According to grinding mechanism the cause of residual stress transform has been explained.

关键词： ceramic grinding residual stress finite element analysis grinding parameter

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.D.Küntz D.Koutroumpa W.R.Dunn A.Foster F.s.Porter D.G.sibeck B.Walsh The Henry A.Rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NAsA Goddard space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOs-OVsQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate sMILE’s(solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing sMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances