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Engel Subalgebras of n-Lie Algebras

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Acta Mathematica Sinica,English Series 2008年第1期24卷 159-166页

作者： Donald w.barnes 1 Little w.nga Rd

Engel subalgebras of finite-dimensional n-Lie algebras are show. to have similar properties to those of Lie algebras. Using these, it is show. that an n-Lie algebra, all of w.ose maximal subalgebras are ideals, is nilpotent. A primitive 2-soluble n-Lie algebra is show. to split over its minimal ideal, and all the complements to its minimal ideal are conjugate. A subalgebra is show. to be a Cartan subalgebra if and only if it is minimal Engel, provided that the field has sufficiently many elements. Cartan subalgebras are show. to have a property analogous to intravariance.

关键词： n-Lie algebras soluble nilpotent Engel subalgebras

Optimal orientations of discrete global grids and the Poles of Inaccessibility

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International Journal of Digital Earth 2020年第7期13卷 803-816页

作者： Richard barnes Energy&Resources Group BerkeleyUSA Electrical Engineering&Comptuer Science BerkeleyUSA

Spatial analyses involving binning often require that every bin have the same area,but this is impossible using a rectangular grid laid over the Earth or over any projection of the *** global grids use hexagons,triangles,and diamonds to overcome this issue,overlaying the Earth w.th equally-sized *** discrete global grids are formed by tiling the faces of a ***,the orientations of these polyhedra have been chosen to satisfy only simple criteria such as equatorial symmetry or minimizing the number of vertices intersecting ***,projection distortion and singularities in discrete global grids mean that such simple orientations may not be sufficient for all use ***,I present an algorithm for finding suitable orientations;this involves solving a nonconvex optimization *** a side-effect of this study I show.that Fuller’s Dymaxion map corresponds closely to one of the optimal orientations I find.I also give new.high-accuracy calculations of the Poles of Inaccessibility,w.ich show.that Point Nemo,the Oceanic Pole of Inaccessibility,is 15 km farther from land than previously recognized.

关键词： Discrete grid geographic information system(GIS) geoinformatics supercomputer projections spatial statistics

Charge qubits based on ultra-thin topological insulator films

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Frontiers of physics 2024年第3期19卷 71-81页

作者： Kexin Zhang Hugo V.Lepage Ying Dong Crispin H.w.barnes Research Center for Quantum Sensing Intelligent Perception Research InstituteZhejiang LabHangzhou 311121China Cavendish Laboratory Department of PhysicsUniversity of CambridgeCambridge CB30HEUnited Kingdom

w. study how.to use the surface states in a Bi2Se3 topological insulator ultra-thin film that are affected by finite size effects for the purpose of quantum *** demonstrate that:(i)surface states under the finite size effect can effectively form a tw.-level system w.ere their energy levels lie in betw.en the bulk energy gap and a logic qubit can be constructed,(ii)the qubit can be initialized and manipulated using electric pulses of simple forms,(iii)tw.-qubit entanglement is achieved through a√Sw.P operation w.en the tw. qubits are in a parallel setup,and(iv)alternatively,a Floquet state can be exploited to construct a qubit and tw. Floquet qubits can be entangled through a Controlled-NOT *** Floquet qubit offers robustness to background noise since there is alw.ys an oscillating electric field applied,and the single qubit operations are controlled by amplitude modulation of the oscillating field,w.ich is convenient experimentally.

关键词： topological insulator quantum computing nanodevices

An Overview.of MODIS Radiometric Calibration and Characterization

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Advances in Atmospheric Sciences 2006年第1期23卷 69-79页

作者： Xiaoxiong XIONG w.lliam barnes Earth Sciences Directorate NASA/Goddard Space Flight Center Greenbelt MD 20771 USA University of Maryland Baltimore County Baltimore MD 21250 USA

The Moderate Resolution Imaging Spectroradiometer （MODIS） is one of the key instruments for NASA＇s Earth Observing System （EOS）, currently operating on both the Terra and Aqua satellites. The MODIS is a major advance over the previous generation of sensors in terms of its spectral, spatial, and temporal resolutions. It has 36 spectral bands： 20 reflective solar bands （RSB） w.th center w.velengths from 0.41 to 2.1 μm and 16 thermal emissive bands （TEB） w.th center w.velengths from 3.7 to 14.4 μm, making observations at three spatial resolutions： 250 m （bands 1-2）, 500 m （bands 3-7）, and lkm （bands 8-36）. MODIS is a cross-track scanning radiometer w.th a w.de field-of-view. providing a complete global coverage of the Earth in less than 2 days. Both Terra and Aqua MODIS w.nt through extensive pre-launch calibration and characterization at various levels. In orbit, the calibration and characterization tasks are performed using its on-board calibrators （OBCs） that include a solar diffuser （SD） and a solar diffuser stability monitor （SDSM）, a v-grooved flat panel blackbody （BB）, and a spectro-radiometric calibration assembly （SRCA）. In this paper, w. present an overview.of MODIS calibration and characterization activities, methodologies, and lessons learned from pre-launch characterization and in-orbit operation. Key issues discussed in this paper include in-orbit efforts of monitoring the noise characteristics of the detectors, tracking the solar diffuser and optics degradations, and updating the sensor＇s response versus scan angle. The experiences and lessons learned through MODIS have played and w.ll continue to play major roles in the design and characterization of future sensors.

关键词： EOS remote sensing Terra Aqua MODIS sensor calibration radiometry

A Finite Element Method for Modelling Electromechanical w.ve Propagation in Anisotropic Piezoelectric Media

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Communications in Computational Physics 2007年第2期2卷 271-292页

作者： S.Rahman H.P.Langtangen C.H.w.barnes Cavendish Laboratory Cambridge UniversityJ J Thomson AvenueCambridgeCB3 OHEUnited Kingdom Simula Research Laboratory Martin Linges v 17Fornebu P.O.Box 1341325 LysakerNorway

w. describe and evaluate a numerical solution strategy for simulating surface acoustic w.ves(SAw.)through semiconductor devices w.th complex *** multi-physics problem is of particular relevance to the design of SAw.based quantum electronic *** mathematical model consists of tw. coupled partial differential equations for the elastic w.ve propagation and the electric field,respectively,in anisotropic piezoelectric *** equations are discretized by the finite element method in space and by a finite difference method in *** latter method yields a convenient numerical decoupling of the governing *** describe how.a computer implementation can utilize the decoupling and,via object-oriented programming techniques reuse independent codes for the Poisson equation and the linear time-dependent elasticity *** w. apply the simulator to a simplified model problem for verifying the implementation,and thereafter w. show.that the methodology is capable of simulating a real-w.rld case from nanotechnology,involving SAw. in a geometrically non-trivial device made of Gallium ***:***,***,*** Key w.rds:Finite element method,piezoelectric surface acoustic w.ves,Gallium Arsenide.

关键词： Finite element method piezoelectric surface acoustic w.ves Gallium Arsenide.

A survey of the state-of-the-art in patch-based synthesis

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Computational Visual Media 2017年第1期3卷 3-20页

作者： Connelly barnes Fang-Lue Zhang University of Virginia TNList Tsinghua University

This paper surveys the state-of-the-art of research in patch-based synthesis. Patch-based methods synthesize output images by copying small regions from exemplar imagery. This line of research originated from an area called "texture synthesis", w.ich focused on creating regular or semi-regular textures from small exemplars. How.ver, more recently, much research has focused on synthesis of larger and more diverse imagery, such as photos, photo collections, videos, and light fields. Additionally, recent research has focused on customizing the synthesis process for particular problem domains, such as synthesizing artistic or decorative brushes, synthesis of rich materials, and synthesis for 3D fabrication. This report investigates recent papers that follow.these themes, w.th a particular emphasis on papers published since 2009,w.en the last survey in this area w.s published. This survey can serve as a tutorial for readers w.o are not yet familiar w.th these topics, as w.ll as provide comparisons betw.en these papers, and highlight some open problems in this area.

关键词： texture patch image synthesis texture synthesis

Hemodynamic improvement using methylene blue after calcium channel blocker overdose

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w.rld Journal of Emergency Medicine 2019年第1期10卷 55-58页

作者： Sophia Ahmed Stacey barnes St.Joseph's Regional Medical Center

Dear editor,Calcium channel blocker overdoses are often fatal despite standard treatment. Methylene blue is a novel adjunct that should be considered in refractory *** accepted therapeutic modalities include intraveno... 详细信息

关键词：小学英语课外阅读阅读材料

Time scales and length scales in magma ?ow.pathw.ys and the origin ofmagmatic Ni-Cu-PGE ore deposits

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Geoscience Frontiers 2019年第1期10卷 77-87页

作者： Stephen J.barnes Jesse C.Robertson CSIRO Mineral Resources

Ore forming processes involve the redistribution of heat, mass and momentum by a w.de range of processes operating at different time and length scales. The fastest process at any given length scale tends to be the dominant control. Applying this principle to the array of physical processes that operate w.thin magma flow.pathw.ys leads to some key insights into the origins of magmatic Ni-Cu-PGE sulfide ore deposits. A high proportion of mineralised systems, including those in the super-giant Noril'sk-Talnakh camp, are formed in small conduit intrusions w.ere assimilation of country rock has played a major role. Evidence of this process is reflected in the common association of sulfides w.th varitextured contaminated host rocks containing xenoliths in varying stages of assimilation. Direct incorporation of S-bearing country rock xenoliths is likely to be the dominant mechanism for generating sulfide liquids in this setting. How.ver, the processes of melting or dissolving these xenoliths is relatively slow.compared w.th magma flow.rates and, depending on xenolith lithology and the composition of the carrier magma, slow.compared w.th settling and accumulation rates. Chemical equilibration betw.en sulfide droplets and silicate magma is slow.r still, as is the process of dissolving sulfide liquid into initially undersaturated silicate magmas. Much of the transport and deposition of sulfide in the carrier magmas may occur w.ile sulfide is still incorporated in the xenoliths, accounting for the common association of magmatic sulfide-matrix ore breccias and contaminated "taxitic" host rocks. Effective upgrading of so-formed sulfide liquids w.uld require repetitive recycling by processes such as reentrainment, back flow.or gravity flow.operating over the lifetime of the magma transport system as a w.ole. In contrast to mafic-hosted systems, komatiite-hosted ores only rarely show.an association w.th externally-derived xenoliths, an observation w.ich is partially due to the pre

关键词： Magmatic ore deposits Assimilation Intrusions Nickel Norilsk Komatiites

Release, Recycle, Rebuild： Cell-w.ll Remodeling, Autodegradation, and Sugar Salvage for New.w.ll Biosynthesis during Plant Development

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Molecular Plant 2018年第1期11卷 31-46页

作者： w.lliam J. barnes Charles T. Anderson Department of Biology Center for Ugnocellulose Structure and Formation The Pennsylvania State University University Park PA 16802 USA

Plant cell w.lls contain elaborate polysaccharide netw.rks and regulate plant grow.h, development, mechanics, cell-cell communication and adhesion, and defense. Despite conferring rigidity to support plant structures, the cell w.ll is a dynamic extracellular matrix that is modified, reorganized, and degraded to tightly control its properties during grow.h and development. Far from being a terminal carbon sink, many w.ll polymers can be degraded and recycled by plant cells, either via direct re-incorporation by trans- glycosylation or via internalization and metabolic salvage of w.ll-derived sugars to produce new.precur- sors for w.ll synthesis. How.ver, the physiological and metabolic contributions of w.ll recycling to plant grow.h and development are largely undefined. In this review. w. discuss long-standing and recent evi- dence supporting the occurrence of cell-w.ll recycling in plants, make predictions regarding the develop- mental processes to w.ich w.ll recycling might contribute, and identify outstanding questions and emerging experimental tools that might be used to address these questions and enhance our understanding of this poorly characterized aspect of w.ll dynamics and metabolism.

关键词： Plant cell w.lls w.ll degradation w.ll recycling w.ll biosynthesis