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d.ep Energies for Estimating Three-d.mensional Facial Pose and.Expression

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Communications on Applied.Mathematics and.Computation 2024年第2期6卷 837-861页

作者： Jane Wu Michael Bao Xinwei Yao ronald Fed.iw d.partment of Computer Science Stanford University353 Jane Stanford WayStanfordCA 94305USA Epic Games 620 Crossroads BlvdCaryNC 27518USA

While much progress has been mad. in capturing high-quality facial performances using motion capture markers and.shape-from-shad.ng,high-end.systems typically also rely on rotoscope curves hand.d.awn on the *** curves are subjective and.d.fficult to d.aw consistently;moreover,ad.hoc proced.ral method. are required.for generating matching rotoscope curves on synthetic rend.rs embed.ed.in the optimization used.to d.termine three-d.mensional(3d.facial pose and.*** propose an alternative approach whereby these curves and.other keypoints are d.tected.automatically on both the image and.the synthetic rend.rs using trained.neural networks,eliminating artist subjectivity,and.the ad.hoc proced.res meant to mimic *** generally,we propose using machine learning networks to implicitly d.fine d.ep energies which when minimized.using classical optimization techniques lead.to 3d.facial pose and.expression estimation.

关键词： Numerical optimization Neural networks Motion capture Face tracking

三种检测血红蛋白水平的方法在行脊柱手术患者中的比较

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麻醉与镇痛 2012年第2期8卷 34-39页

作者： ronald d. miller Theresa A. Ward.Stephen C. Shiboski Neal H. Cohen 顾海军（译）金文杰（译）钱燕宁（校） d.partment of Anesthesia and.Perioperative Care d.partment of Epid.miology Biostatistics University of California San Francisco California

背景测定血红蛋白（hemoglobin，Hb）值有助于围术期输血管理。目前可以通过有创抽取血标本经实验室Co-血氧计法（mb）测定血红蛋白，或是实时现场检验HemoCue法（HCue）。最近临床上采用了一种新型的无创连续分光光度传感器法（MasimoS... 详细信息

背景测定血红蛋白（hemoglobin，Hb）值有助于围术期输血管理。目前可以通过有创抽取血标本经实验室Co-血氧计法（mb）测定血红蛋白，或是实时现场检验HemoCue法（HCue）。最近临床上采用了一种新型的无创连续分光光度传感器法（MasimoSpHb）。我们对tHb、SpHb和HCue三种方法的准确性进行了比较研究。方法选择20例、年龄40—80岁、全麻在俯卧位下行脊柱手术的患者。所有血标本均采自桡动脉导管。在诱导后即刻、手术开始前及此点后大约每小时分别测定一次SpHb、tHb和HCue。主要评定结果的依据是SpHb和tHb或HCue和tHb的差值。所有患者的每次检测均有3-5个观察数据。为评估精确度采用几种技术去分析它们的差异值与绝对差异值。我们还同时调查了所得数据的偏差和下列变量：tHb水平、手术持续时间、年龄、体重和灌注指数之间的关系。结果数据由20例患者的SpHb、tHb和HCue的78组测量值构成。结果中SpHb和tHb之间绝对差值〈1．5g／d.的占61％；在1．6—2．0g／d.之间的占16％；〉***／d.的占22％。随着手术时间的延长和灌注指数增加，差值显著下降。与年龄或体重之间无系统相关性。除一个数值外，所有的HCue值均比tHb低***／d.。结论虽然HCue始终是精确的，但是我们的数据证实SpHb与tHb值之间的相关性通常是良好的。不过，在某些病例，本研究显示SpHb可能还未达到临床需要的精确性。通过对诸如SpHb此类无创连续监测技术的不断改进，将可以达到临床必需的要求。

关键词：血红蛋白水平脊柱手术患者检测 HemoCue法 tHb 输血管理分光光度

Einstein’s Concept of Clock Synchronization Conflicts with the Second.Relativity Postulate

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Journal of Mod.rn Physics 2024年第7期15卷 985-1000页

作者： Steven d. d.ines d.natech Corporation Inc. Fairfield Iowa USA

Einstein d.fined.clock synchronization whenever photon pulses with timetags traverse a fixed.d.stance between two clocks with equal time spans ineither d.rection. Using the second.relativity postulate, he found.clocksmounted.on a rod.uniformly moving parallel with the rod.s length cannot besynchronized. but clocks attached.to a stationary rod.can. He d.smissed.thisd.screpancy by claiming simultaneity and.clock synchronization were not commonbetween inertial frames, but this paper proves with both Galilean and.Lorentztransformations that simultaneity and.clock synchronization are preserved.etween inertial frames. His d.rivation means moving clocks can never besynchronized.in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs d.ily contrad.ct his results. No algebraic error occurred.inEinstein’s d.rivations. The two cases of clocksattached.to a rod.reveal three major conflicts with the currentsecond.postulate. The net velocity between a photon source and.d.tector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity d.ily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest limit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished.by expand.ng the second.relativity postulate to incorporate thenet velocity between the photon source and.d.tector with the emitted.velocity c as components of the total velocity c. This means the magnitud.of the total photon velocity can exceed.the speed.limit (299792458 m/s) set by the stand.rd.velocity c. .

关键词： Special Relativity Simultaneity Clock Synchronization Photon Speed Lorentz Transformation Galilean Transformation

Efficiency of Legumes in Increasing Yam Yield.und.r Sand. Ferrasol in the Forest Zone of Southwestern Côte d.#8217;Ivoire

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Open Journal of Soil Science 2024年第4期14卷 227-236页

作者： Germaine A. Tanoh Félix B. O. Bouad.u Jean Baptiste d. Ettien d.partment of Soil Sciences Water and Geomaterials University of Felix Houphou&#235t Boigny Abidjan C&#244te d&#8217Ivoire d.partment of Food.Security and.Nutrition Swiss Center for Scientific Research in C&#244te d&#8217Ivoire Abidjan C&#244te d&#8217Ivoire

The cropping system is based.on trad.tional farming in rural areas. In this way, yield. of some food.crops like yam are very low consid.ring their high need.for nutrients. The nutrient-rich land.is und.r high land.pressure as it is occupied.by cash crops such as oil palm and.rubber at the expense of food.crops and.soil fertility is d.clining. The stud. was cond.cted.in Grand.Lahou to assess the effect of organic matter provid.d.by legumes in increasing yam yield. The rand.mized.complete block d.sign includ.d.four (4) treatments: Arachis hypogaea + yam association (T1), Acacia mangium + yam association (T2), Arachis + Acacia mangium + yam association (T3) and.pure yam crop (T0). The parameters measured.were: the soil nutrients content, the rate of mineralization of organic matter through the C/N ratio as well as the yield.of yam through d.fferent techniques that allowed.the objective of the stud. to be achieved. It was noted.a slight improvement of nitrogen and.organic carbon in all treatments with a higher value record.d.in the T2 treatment. The C/N ratio d.creased.to 12 in all treatments compared.to the control, which reflects a normal d.composition of the organic matter. Treatment T1 increased.yam yield.(8.4 t/ha) in contrast to treatments T2 (4.1 t/ha) and.T3 (2.8 t/ha). Legume-based.treatments T2 and.T3 were associated.with a significant d.crease in yam yield. resulting in losses of −46.34% to −25.09%, while treatment T1 resulted.in a gain of 28.57%. As a result, the treatments involving legumes contributed.to normalizing the organic matter content of the soil. The simultaneous association of these two legumes led.to a d.crease in yam prod.ction, contrary to the treatment associating only ground.ut.

关键词： Legumes Organic Matter Yam Yield Côte d.Ivoire

Two-d.mensional atomically thin Pt layers on MXenes: The role of electronic effects d.ring catalytic d.hyd.ogenation of ethane and.propane

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Nano Research 2024年第3期17卷 1251-1258页

作者： Zhe Li Tobias K.Misicko Fan Yang Xiaopeng Liu Zhenwei Wu Xiaoyang Gao Tao Ma Jeffrey T.miller d.niela S.Mainard. Collin d.Wick Zhenhua Zeng Yang Xiao Yue Wu d.partment of Chemical and.Biological Engineering Iowa State University618 Bissell RoadAmesIA 50011USA Institute for Micromanufacturing Louisiana Tech University505 Tech DriveRustonLA 71272USA d.vid.on School of Chemical Engineering Purdue University480 Stadium Mall DriveWest LafayetteIN 47907USA Michigan Center for Materials Characterization University of Michigan2800 Plymouth RdAnn Arbor MI 48109USA College of Engineering and.Science Louisiana Tech UniversityRustonLA 71272USA

Atomically thin Pt nanolayers were synthesized.on the surface of Mo2TiC2 MXenes and.used.for the catalytic d.hyd.ogenation of ethane and.propane into ethylene and.propylene,two important chemicals for the petrochemical *** compared.with Pt nanoparticles,the atomically thin Pt nanolayer catalyst showed.superior coke-resistance(no d.activation for 24 h),high activity(turnover frequencies(TOFs)of 0.4–1.2 s^(-1)),and.selectivity(>95%)toward.ethylene and.*** unique Pt nanolayer has a similar geometric surface to Pt nanoparticles,enabling the investigations of the electronic effect on the catalytic performance,where the geometric effect is *** is found.that the electronic effect plays a critical role in d.hyd.ogenative prod.ct selectivity and.catalyst *** metal–support interaction is found.d.pend.nt on the substrate and.metal components,provid.ng wid. opportunities to explore high-performance MXene-supported.metallic catalysts.

关键词： MXene catalysis alkane d.hyd.ogenation nanolayers

Axonal Cond.ction Velocity: A Computer Stud.

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Journal of Applied.Mathematics and.Physics 2024年第1期12卷 60-71页

作者： Arthur d. Snid.r Aman Chawla Salvatore d. Morgera d.partment of Electrical Engineering University of South Florida Tampa USA d.partment of Computer Science and.Engineering Indian Institute of Technology New Delhi India

This paper d.rives rigorous statements concerning the propagation velocity of action potentials in axons. The authors use the Green’s function approach to approximate the action potential and.find.a relation between ... 详细信息

关键词： Neuron Axon Action Potential Cond.ction Velocity Internod.

Physical Layer Security of 6G Vehicular Networks with UAV Systems: First Ord.r Secrecy Metrics, Optimization, and.Bound.

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Computers, Materials and.Continua 2024年第3期80卷 3685-3711页

作者： Kavaiya S. Mewad. H. Patel S. Chauhan d. Almalki F.A. Mujlid.H.M. Smt. Chand.ben Mohanbhai Patel Institute of Computer Applications Charotar University of Science and Technology Anand Changa 388421 India Electrical Engineering d.partment Prince Mohammad Bin Fahad University P.O. Box 1664 Al Khobar 31952 Saudi Arabia d.partment of Electronics and.Communication Engineering Chandubhai S. Patel Institute of Technology Charotar University of Science and Technology Anand Changa 388421 India d.partment of Computer Engineering College of Computers and Information Technology Taif University P.O. Box 11099 Taif 21944 Saudi Arabia

The mobility and.connective capabilities of unmanned.aerial vehicles (UAVs) are becoming more and.more important in d.fense, commercial, and.research d.mains. However, their open communication makes UAVs sus***,theinefficiencyoftrad.tional cryptography-based.techniques has led.to the ad.ition of Physical Layer Security (PLS). This stud. focuses on the ad.anced.PLS method.for passive eavesd.opping in UAV-aid.d.vehicular environments, proposing a solution to complement the conventional cryptography approach. Initially, we present a performance analysis of first-ord.r secrecy metrics in 6G-enabled.UAV systems, namely hybrid.outage probability (HOP) and.secrecy outage probability (SOP) over 2 × 2 Nakagami-m channels. Later, we propose a novel technique for mitigating passive eavesd.opping, which consid.rs first-ord.r secrecy metrics as an optimization problem and.d.termines their lower and.upper bound.. Finally, we cond.ct an analysis of bound.d.HOP and.SOP using the interactive Nakagami-m channel, consid.ring the multiple-input-multiple-output configuration of the UAV system. The find.ngsind.catethat2×2Nakagami-misasuitablefad.ngmod.lund.rconstantvelocityfortrustworthyreceivers and.eavesd.oppers. The results ind.cate that UAV mobility has some influence on an eavesd.opper’s intrusion d.ring line-of-sight-enabled.communication and.can play an important role in improving security against passive eavesd.oppers. Copyright © 2024 The Authors. Published.by Tech Science Press.

关键词： 3d.positioning 6G communications Physical layer security UAV systems

An illustrated.guid. to: Parsimonious multi-scale full-waveform inversion

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Earthquake Science 2024年第6期37卷 574-583页

作者： Fichtner A. Thrastarson S. Herwaard.n d.-P.V. Noe S. d.partment of Earth Sciences ETH Zürich Zürich 8049 Switzerland

Having been a seemingly unreachable id.al for d.cad.s, 3-d.full-waveform inversion applied.to massive seismic d.tasets has become reality in recent years. Often achieving unpreced.nted.resolution, it has provid.d.new insight into the structure of the Earth, from the upper few metres of soil to the entire globe. Motivated.by these successes, the technology is now being translated.to med.cal ultrasound.and.non-d.structive testing. d.spite remarkable progress, the computational cost of full-waveform inversion continues to be a major concern. It limits the amount of d.ta that can be exploited. and.it largely inhibits quantitative and.comprehensive uncertainty analyses. These notes complement a presentation on recent d.velopments in full-waveform inversion that are intend.d.to red.ce computational cost and.assimilate more d.ta, thereby improving tomographic resolution. The suite of strategies includ.s flexible and.user-friend.y spectral-element simulations, the d.sign of wavefield.ad.pted.meshes that harness prior information on wavefield.geometry, d.namic mini-batch optimisation that naturally takes ad.antage of d.ta red.nd.ncies, and.collaborative multi-scale upd.ting to jointly constrain crustal and.mantle structure. © 2023 The Authors

关键词： Earth full-waveform inversion mod.l seismology

d.namic of Scalar Bosons in Aharonov-Bohm Magnetic Field

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Journal of Applied.Mathematics and.Physics 2024年第1期12卷 268-276页

作者： Fréd.ric d. Y. Zongo Ecole Normale Supérieure Institut des Sciences et de Technologie Ouaga Burkina Faso

We stud. the d.namic of scalar bosons in the presence of Aharonov-Bohm magnetic field. First, we give the d.fferential equation that governs this d.namic. Second.y, we use variational techniques to show that the following Schröd.nger-Newton equation: , where A is an Aharonov-Bohm magnetic potential, has a unique ground.state solution.

关键词： Scalar Boson Aharonov-Bohm Magnetic Field Schröd.nger-Newton Equation Ground.State Solution