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Journal of Materials Science & Technology 2009年第2期25卷 277-280页

作者： M. cheng S.h. Zhang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Research results on the viscous flow deformation behavior of bulk amorphous alloy in different systems are reviewed. The material exhibits an ideal Newtonian fluid at a high temperature. Analytical solution of lamellar fluid flow behavior is used to discuss the viscous flow behavior of the bulk amorphous alloy in the supercooled liquid state. A material model, which describes such deformation behavior of Mg6ocusoYlo amorphous alloy, is introduced into the finite element method of microformin8 process. Surface feature size was investigated and found not sensitive to the micro formability. Bulk amorphous alloy may possibly be applied to microelectro-mechanical-systems （MEMS） fabrication.

关键词： Bulk amorphous alloy Supercooled liquid state Micro formability Lamellar fluid flow

Engineered nucleus-free mesenchymal stem cells (MScs) for the targeted delivery of therapeutics to disease site

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Genes & Diseases 2023年第2期10卷 310-312,I0001页

作者： Zander Schwartz Piao Zhao Annie Wang Guozhi Zhao Wei Zeng Yonghui Wang hue h. Luu Rex c. haydon Tong-chuan he Russell R. Reid Jason Strelzow School of Biomedical Engineering Vanderbilt UniversityNashvilleTN 37235USA Molecular Oncology Laboratory Department of Orthopedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Departments of Orthopaedic Surgery and Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of clinical Laboratory Medicine Shanghai Jiaotong University School of MedicineShanghai 200000China Laboratory of craniofacial Suture Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA

Specialized therapeutic delivery, or use of pharmaceuticals and other biomaterials to target specific parts of the body or diseased tissue, has long been sought as an ideal way of treating human diseases. A recent article published in Nature Biomedical Engineering revealed an innovative strategy to engineer nucleus-free human mesenchymal stem cells (MScs) for targeted delivery of therapeutics to disease site.1 MScs have emerged as promising vehicles of therapeutic delivery.2,3 MScs are undifferentiated pluripotent stem cells derived from areas such as bone marrow and adipose tissue.4,5 MScs are sought after for their chemotaxis, or ability to home towards a chemical stimulus, and capacity for modification with elements such as chemoattractant receptors and adhesion molecules.1 These properties allow for site-specific and minimally-invasive therapeutic administration and treatment.

关键词： targeted delivery sought

Mesh-Free Interpolant Observables for continuous Data Assimilation

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Annals of Applied Mathematics 2022年第3期38卷 296-355页

作者： Animikh Biswas Kenneth R.Brown vincent R.Martinez Department of Mathematics & Statistics University of Maryland-Baltimore County1000 Hilltop CircleBaltimoreMD 21250USA Department of Mathematics University of California-DavisOne Shields AvenueDavisCA 95616USA Department of Mathematics & Statistics CUNY Hunter College695 ParkAveNewYorkNY10065USA Department of Mathematics CUNY Graduate Center3655th AveNew YorkNY10016USA

This paper is dedicated to the expansion of the framework of general interpolant observables introduced by Azouani,Olson,and Titi for continuous data assimilation of nonlinear partial differential *** main feature of this expanded framework is its mesh-free aspect,which allows the observational data itself to dictate the subdivision of the domain via partition of unity in the spirit of the so-called Partition of Unity Method by Babuska and *** an application of this framework,we consider a nudging-based scheme for data assimilation applied to the context of the two-dimensional Navier-Stokes equations as a paradigmatic example and establish convergence to the reference solution in all higher-order Sobolev topologies in a periodic,mean-free *** convergence analysis also makes use of absorbing ball bounds in higherorder Sobolev norms,for which explicit bounds appear to be available in the literature only up to h^(2);such bounds are additionally proved for all integer levels of Sobolev regularity above h^(2).

关键词： continuous data assimilation nudging 2D Navier-Stokes equations general interpolant observables synchronization higher-order convergence partition of unity mesh-free Azounai-Olson-Titi algorithm

Self-learning Fuzzy Navigation of Mobile Vehicle

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Self-learning Fuzzy Navigation of Mobile Vehicle

Discrete modeling of rock joints with a smooth-joint contact model

1996 3rd International conference on Signal Processing(IcSP’96)

作者： N.h.c.Yung c.Ye Department of Electrical and Electronic Engineering The University of hong Kong

＜正＞This paper describes a self-learning navigation method which utilizes fuzzy logic and reinforcement learning for navigation of a mobile vehicle in uncertain environments. The proposed navigator consists of three modules: Obstacle Avoidance,Move to Goal and Fuzzy Behavior *** fuzzy rules of the on-line obstacle avoidance are learnt through reinforcement learning.A new and powerful method is proposed to constructed these rules *** effectiveness of the learning method and the whole navigator are verified by simulation.

关键词： Navigation Fuzzy logic Input variables Road vehicles Path planning Modular construction Automotive engineering Learning systems Vehicle dynamics Mathematical model

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第1期6卷 1-12页

作者： c.Lambert c.coll Department of civil and Natural Resources Engineering University of CanterburyPrivate Bag 4800 Christchurch 8140 New Zealand Golder Associates Christchurch New Zealand

Structural defects such as joints or faults are inherent to almost any rock *** many situations those defects have a major impact on slope stability as they can control the possible failure *** a good estimate of their strength then becomes *** roughness of a structure is a major contributor to its strength through two different aspects,*** morphology of the surface(or the shape)and the strength of the asperities(related to the strength of the rock).In the current state of practice,roughness is assessed through idealized descriptions(Patton strength criterion)or through empirical parameters(Barton JRc).In both cases,the multi-dimensionality of the roughness is *** this study,we propose to take advantage of the latest developments in numerical ***3D photogrammetry and/or laser mapping,practitioners have access to the real morphology of an exposed *** derived triangulated surface was introduced into the DEM(discrete element method)code PFc3D to create a synthetic rock *** interaction between particles on either side of the discontinuity was described by a smooth-joint model(SJM),hence suppressing the artificial roughness introduced by the particle *** tests were then performed on the synthetic rock joint.A good correspondence between strengths predicted by the model and strengths derived from well-established techniques was obtained for thefirst *** the benefits of the methodology is the possibility offered by the model to be used in a quantitative way for shear strength estimates,to reproduce the progressive degradation of the asperities upon shearing and to analyze structures of different scales without introducing any empirical relation.

关键词： Rock joint Shear strength DEM simulations Smooth-joint model

correlations between IMc thickness and three factors in Sn-3Ag-0.5cu alloy system

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中国有色金属学会会刊：英文版 2007年第4期17卷 686-690页

作者：孟工戈 T. Takemoto h. Nishikawa college of Materials Science and Engineering Harbin University of Science and Technology Joining and Welding Research Institute Osaka UniversityIbalaki Osaka 567-0047 Japan

The effects of Ni content, soldering temperature and time on the IMc thickness in Sn-3Ag-0.5cu and Sn-3Ag-0.5cu-0.2co alloys were researched using uniform design method and computer programs. For each alloy, the factors were divided into three levels in the experiment. Two correlative equations are given by regression. They indicate that the effects of three factors on the function are in the mutual and quadratic forms. And the analysis of variance shows the equations are sound and meaningful. Using the equations, it is easy to search, predict and control the IMc thickness. The existence of element co accelerates the crystallization and growing up of IMc.

关键词：锡银铜合金无铅焊料金属间化合物厚度均匀设计

System Performance of IEEE 802.15.4 Low Rate Wireless PAN using UWB as Alternate-PhY Layer

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System Performance of IEEE 802.15.4 Low Rate Wireless PAN us...

An Analysis of the Invariance and conservation Laws of Some classes of Nonlinear Ostrovsky Equations and Related Systems

IEEE第14届国际个人无线移动通信大会

作者： Francois chin chi-chung Ko Institute for Infocomm Research of Singapore Department of Electrical Engineering National University of Singapore

Personal Area Networks (PANs) are expected toplay an important role in future mobile ad-hoc wirelesscommunications and information systems. This paper proposes aUWB-based alternate PhY layer for 802.1

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chinese Physics Letters 2011年第1期28卷 1-4页

作者： K. Fakhar A. h. Kara Department of Mathematics Faculty of Science Universiti Teknologi Malaysia 81310 UTM Skudai Johor Malaysia School of Mathematics and centre for Differential Equations Continuum Mechanics and Applications University of the Witwatersrand Johannesburg P Bag 3 Wits 2050 South Africa

A large class of partial differential equations in the modelling of ocean waves are due to Ostrovsky. We determine the invariance properties （through the Lie point symmetry generators） and construct classes of conservation laws for some of the models. In the latter case, the method involves finding the ＇multipliers＇ associated with the conservation laws with a stronger emphasis on the ＇higher-order＇ ones. The relationship between the symmetries and conservation laws is investigated by considering the invariance properties of the multipliers.

关键词： Mathematical physics Statistical physics and nonlinear systems

Observation of Rotational Bands in Neutron—Rich ^106Mo Nucleus

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chinese Physics Letters 2002年第2期19卷 180-183页

作者：许瑞清 J.h.hamilton DepartmentofPhysics TsinghuaUniversityBeijing100084 DepartmentofPhysics VanderbiltUniversityNashvilleTN37235USA

The rotational bands up to a spin of 16 in the neutron-rich 106Mo nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events following spontaneous fission of 252cf with a Gammasphere detector array. The ground-state band, the one-phonon and two-phonon γ-vibrational bands, as well as a quasi-particle band have been confirmed and expanded. The other four collective rotational bands, three proposed as two-quasi-particle bands and one proposed as a β-vibrational band, have been newly observed. The characteristics of these collective bands and the possible configurations for the quasi-particle bands are discussed.

关键词： Gamma rays

Electrical Properties of Li-doped P-type ZnO ceramics

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Journal of Materials Science & Technology 2009年第3期25卷 314-318页

作者： A.h. Salama F.F. hammad Physical chemistry Department National Research Center Inorganic chemistry Department National Research Center

Li-doped p-type ZnO ceramics were prepared by conventional methods according to the chemical formula Zn1-xLixO2 where x=0.5, 1.0, 1.5 and 2.0 mole fraction, respectively. The crystal structures of the prepared samples were studied by X-ray diffraction analysis. The dielectric properties （including dielectric constant ε′ and dielectric loss ε″） and dc-electrical conductivity [σ（Ω^-***^-1）] were investigated. The dielectric constant ε′ was sharply decreased at the low frequency range and independent on frequency at high frequency range. Otherwise, the dielectric loss ε″ varied with frequency and showed absorption peak located from 200 hz to 4 khz and moved to higher frequency as the concentration of Li＋ doped increased. It was found that dcelectrical conductivity logσ varied from -9 to -5 and the energy gap width were calculated by using Arrhenius equation. The p-type conductivity of Li-doped ZnO may be attributed to the formation of a Lizn-Lii donor complex, which is limited by reducing the amount of Lii.

关键词： P-type ZnO ceramics Dielectric constant Dielectric loss dc-conductivity