检索结果-南通市图书馆

Parametric Study of Low Frequency Broadband Rectilinear-to-Rotary Vibrational Energy Harvesting

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nanjing university of Aeronautics and Astronautics 2018年第1期35卷 1-9页

作者： Chen Jingfan Deng Wei Wang Ya Inman Dan department of Mechanical Engineering Stony Brook University department of Mechanical Engineering Texas A&M University department of Aerospace Engineering University of Michigan

A parametric study of a high-power-density dual resonator for achieving low frequency broadband electromagnetic energy harvesting is *** dual resonator consists of a rectilinear oscillator(R_LO)performing magnetic levitation and a rotary oscillator(R_TO)performing electromagnetic coupling through a stator and a *** oscillators,coupled by magnetic forces generated by a set of arc permanent magnets,radially magnetized and centro-symmetrically fixed onto the R_LO and the rotor of the R_TO achieve the reciprocating-to-rotary motion conversion and frequency ***,the dual resonator is able to convert stochastic reciprocating motion into controllable rotation,provide intrinsic frequency up-conversion,use non-contact magnetic coupling to provide near loss-free energy transfer and be configured into specific applications to obtain and maintain high-energy orbits of multi-stable energy *** solely focusing on developing a dual resonator provides substantial benefits,its dynamic behavior is unclear,thus electromagnetic-dynamic governing equations are derived,and a curve fitting model of restoring torque of R_TO under different repulsive magnets configurations are developed to predict key characteristics and to improve performance of the electromechanical *** analysis is carried out for providing aquantitative guidance of customizing the harvester to achieve an optimal power density.

关键词： curve fitting model non-contact rectilinear-to-rotary motion transformation frequency up-conversion systematic modeling parametric study

Ultra-Slow Atomic Beam Generation by Velocity Selective Resonance

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2008年第5期25卷 1646-1648页

作者：马红玉成华东王育竹刘亮 METCALF Harold Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 Graduate School of the Chinese Academy of Sciences Beijing 100049 department of Physics and Astronomy Stony Brook University Stony Brook NY 11794-3800 USA

We describe a method to generate an ultra-slow atomic beam by velocity selective resonance （VSR）. A VSR experiment on a metastable helium beam in a magnetic field is presented and the results show that the transverse velocity of the deflected beam can be cooled and precisely controlled to less than the recoil velocity, depending on the magnitude of the magnetic field. We extend this idea to a cold atomic cloud to produce an ultra-slow 87Rb beam that can be used as a source of an atomic fountain clock or a space clock.

关键词： supernova explosion proto-neutron star shock wave

PDE-BASED MEDIAL AXIS EXTRACTION AND SHAPE MANIPULATION OF ARBITRARY MESHES

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2008年第4期21卷 609-625页

作者： Haixia DU Terry YOO Hong QIN Sterne Kessler Goldstein & Fox P.L.L.C. Washington 20005 USA. National Library of Medicine National Institutes of Health Bethesda 20894 USA. Computer Science department Stony Brook University Stony Brook NY 11794 USA.

Shape skeletonization （i.e., medial axis extraction） is powerful in many visual computing applications, such as pattern recognition, object segmentation, registration, and animation. In this paper, the authors expand the use of diffusion equations combined with distance field information to approximate medial axes of arbitrary 3D differential properties. It offers an alternative solids represented by polygonal meshes based on their but natural way for medial axis extraction for commonly used 3D polygonal models. By solving the PDE along time axis, this system can not only quickly extract diffusion-based medial axes of input meshes, but also allow users to visualize the extraction process at each time step. In addition, the proposed model provides users a set of manipulation toolkits to sculpt extracted medial axes, then use diffusion-based techniques to recover corresponding deformed shapes according to the original input datasets. This skeleton-based shape manipulation offers a fast and easy way for animation and deformation of complicated mesh objects.

关键词： Diffusion Equation Medial Axis Extraction PDE techniques Polygonal Meshes Shape Manipulation.

Full-field mapping of internal strain distribution in red sandstone specimen under compression using digital volumetric speckle photography and X-ray computed tomography

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2015年第2期7卷 136-146页

作者： Lingtao Mao Jianping Zuo Zexun Yuan Fu-Pen Chiang State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology (Beijing) Laboratory for Experimental Mechanics Research Stony Brook University department of Mechanical Engineering Stony Brook University

It is always desirable to know the interior deformation pattern when a rock is subjected to mechanicalload. Few experimental techniques exist that can represent full-field three-dimensional （3D） straindistribution inside a rock specimen. And yet it is crucial that this information is available for fully understandingthe failure mechanism of rocks or other geomaterials. In this study, by using the newlydeveloped digital volumetric speckle photography （DVSP） technique in conjunction with X-ray computedtomography （CT） and taking advantage of natural 3D speckles formed inside the rock due to materialimpurities and voids, we can probe the interior of a rock to map its deformation pattern under load andshed light on its failure mechanism. We apply this technique to the analysis of a red sandstone specimenunder increasing uniaxial compressive load applied incrementally. The full-field 3D displacement fieldsare obtained in the specimen as a function of the load, from which both the volumetric and the deviatoricstrain fields are calculated. Strain localization zones which lead to the eventual failure of the rock areidentified. The results indicate that both shear and tension are contributing factors to the failuremechanism. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Red sandstone Strain localization Uniaxial compression Digital volumetric speckle photography(DVSP) X-ray micro-tomography

Self-adjustable hyper-graphs for video pose estimation based on spatial-temporal subspace construction

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2022年第3期65卷 260-262页

作者： Jizhou MA Shuai LI Hong QIN Aimin HAO Qinping ZHAO State Key Laboratory of Virtual Reality Technology and Systems Beihang University department of Computer Science Stony Brook University

Dear editor,In recent years many supervised video pose estimation methods have achieved growing successes based on well-labeled training datasets. Nonetheless, when facing roughly-labeled training data, it still remains challenging to intrinsically encode the video contents’ spatial-temporal coherency for robust video pose *** researches aimed to directly improve and refine the existing confidence maps by combining the spatial-temporal structure models [1, 2]. Li et al.

关键词： Video Pose Estimation Self-adjustable Hyper-graph Spatial-temporal Subspace Exploration Maximum Matching Subspace Operator Action Pattern

同方期刊数据库

Orthopedic implants and devices for bone fractures and defects:Past,present and perspective

在线全文

学校读者我要写书评

暂无评论

Engineered Regeneration 2020年第1期1卷 6-18页

作者： Tiffany Kim Carmine Wang See Xiaochun Li Donghui Zhu department of Biomedical Engineering Stony Brook UniversityStony BrookNew York 11794United States department of Mechanical and Aerospace Engineering &Department of Materials Science and EngineeringUniversity of California Los AngelesLos AngelesCA 90095United States

Bone is a unique tissue that is capable of repairing itself after ***,there are certain instances of fractures and defects that require clinical intervention for proper alignment and *** with any implant,careful consideration of the material used to create the implants to treat these problems is *** the incorrect material is chosen,the implants themselves can lead to bone fractures or defects,or bone healing may not take place at *** three classes of biomaterials-metals,ceramics,and polymers-have been used in the treatment of both bone fractures and bone defects,and each has its own unique benefits and limitations for its ***,composites of these different materials have also been created to try to take advantage of all the different benefits offered by each different *** review highlights different materials that have been used for the development of internal fixators and bone graft substitutes to treat fracture and bone defects as well as their limitations and needed future research.

关键词： Bone scaffold Bone fracture Bone defect Orthopedic implant Orthopedic device

Examining the model dependence of the determination of kinetic freeze-out temperature and transverse flow velocity in small collision system

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2018年第11期29卷 254-270页

作者： Hai-Ling Lao Fu-Hu Liu Bao-Chun Li Mai-Ying Duan Roy A.Lacey Institute of Theoretical Physics & State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi University departments of chemistry & Physics Stony Brook University

The transverse momentum distributions of the identified particles produced in small collision systems at the Relativistic Heavy Ion Collider(RHIC) and Large Hadron Collider(LHC) have been analyzed by four models. The first two models utilize the blast-wave model with different statistics. The last two models employ certain linear correspondences based on different *** four models describe the experimental data measured by the Pioneering High Energy Nuclear Interaction eXperiment, Solenoidal Tracker at RHIC, and A Large Ion Collider Experiment collaborations equally well. It is found that both the kinetic freeze-out temperature and transverse flow velocity in the central collisions are comparable with those in the peripheral collisions. With the increase of collision energy from that of the RHIC to that of the LHC,the considered quantities typically do not decrease. Comparing with the central collisions, the proton–proton collisions are closer to the peripheral collisions.

关键词： Kinetic freeze-out temperature Transverse flow velocity Small collision system Central collisions Peripheral collisions

Chaos,Transport and Mesh Convergence for Fluid Mixing

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2008年第3期24卷 355-368页

作者： H. Lim Y. Yu J. Glimm X.L. Li D.H. Sharp department of Applied Mathematics and Statistics Stony Brook University Stony Brook NY 11794-3600 USA Computational Science Center Brookhaven National Laboratory Upton N~ 11793-6000 USA Los Alamos National Laboratory Los Alamos NM USA

Chaotic mixing of distinct fluids produces a convoluted structure to the interface separating these fluids. For miscible fluids （as considered here）, this interface is defined as a 50% mass concentration isosurface. For shock wave induced （Richtmyer-Meshkov） instabilities, we find the interface to be increasingly complex as the computational mesh is refined. This interfacial chaos is cut off by viscosity, or by the computational mesh if the Kolmogorov scale is small relative to the mesh. In a regime of converged interface statistics, we then examine mixing, i.e. concentration statistics, regularized by mass diffusion. For Schmidt numbers significantly larger than unity, typical of a liquid or dense plasma, additional mesh refinement is normally needed to overcome numerical mass diffusion and to achieve a converged solution of the mixing problem. However, with the benefit of front tracking and with an algorithm that allows limited interface diffusion, we can assure convergence uniformly in the Schmidt number. We show that different solutions result from variation of the Schmidt number. We propose subgrid viscosity and mass diffusion parameterizations which might allow converged solutions at realistic grid levels.

关键词： Schmidt number mass diffusion turbulence multiphase flow

Quantum Fibrations:Quantum Computation on an Arbitrary Topological Space

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第11期40卷 2693-2718页

作者： Kazuki IKEDA Co-design Center for Quantum Advantage(C2QA)&Center For Nuclear Theory Department of Physics and AstronomyStony Brook UniversityStony BrookUSA department of Mathematics and Statistics&Centre for Quantum Topology and Its Applications(quanTA) University of SaskatchewanSaskatoonCanada

Using operator algebras,we extend the theory of quantum computation on a graph to a theory of computation on an arbitrary topological *** computation is usually implemented on finite discrete sets,and the purpose of this study is to extend this to theories on arbitrary *** conventional theory of quantum computers can be viewed as a simplified algebraic geometry theory in which the action of SU(2)is defined on each point of a discrete *** this study,we extend this in general as a theory of quantum fibrations in which the action of the von Neumann algebra is defined on an arbitrary topological *** quantum channel is then naturally extended as a net of von Neumann *** allows for a more mathematically rigorous discussion of general theories,including physics and chemistry,which are defined on sets that are not necessarily discrete,from the perspective of quantum computer science.

关键词： Quantum computation operator algebra von Neumann algebra fibration quantum computational chemistry complexity theory