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Very-high-frequency probes for atomic force microscopy with silicon optomechanics

Microsystems & Nanoengineering 2022年第2期8卷 35-48页

作者： l.Schwab P.E.Allain N.Mauran X.Dollat l.Mazenq D.lagrange M.Gély S.Hentz G.Jourdan I.Favero B.legrand laboratoire d'Analyse et d'Architecture des Systemes Universite de ToulouseCNRS UPR 800131031 ToulouseFrance laboratoire Materiaux et Phenomenes Quantiques Universite de ParisCNRS UMR 716275013 ParisFrance Universite Grenoble Alpes CEALETIMinatec Campus38000 GrenobleFrance

Atomic force microscopy(AFM)has been consistently supporting nanosciences and nanotechnologies for over 30 years and is used in many fields from condensed matter physics to *** enables the measurement of very weak forces at the nanoscale,thus elucidating the interactions at play in fundamental ***,we leverage the combined benefits of micro/nanoelectromechanical systems and cavity optomechanics to fabricate a sensor for dynamic mode AFM at a frequency above 100 *** frequency is two decades above the fastest commercial AFM probes,suggesting an opportunity for measuring forces at timescales unexplored thus *** fabrication is achieved using very-large-scale integration technologies derived from photonic silicon *** probe's optomechanical ring cavity is coupled to a 1.55 pm laser light and features a 130 MHz mechanical resonance mode with a quality factor of 900 in air.A limit of detection in the displacement of 3×10^(-16)m/VHz is obtained,enabling the detection of the Brownian motion of the probe and paving the way for force sensing experiments in the dynamic mode with a working vibration amplitude in the picometer *** inserted in a custom AFM instrument embodiment,this optomechanical sensor demonstrates the capacity to perform force-distance measurements and to maintain a constant interaction strength between the tip and sample,an essential requirement for AFM *** indeed show a stable closed-loop operation with a setpoint of 4 nn/nm for an unprecedented subpicometer vibration amplitude,where the tip-sample interaction is mediated by a stretched water meniscus.

关键词： cavity maintain instrument

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A review:On path planning strategies for navigation of mobile robot

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Defence Technology（防务技术） 2019年第4期15卷 582-606页

作者： B.K. Patle Ganesh Babu l Anish Pandey D.R.K. Parhi A. Jagadeesh Department of Mechanical Engineering CVR College of Engineering Hyderabad India Department of Mechatronics Engineering Tishik International University Erbil Iraq Department of Mechanical Engineering KITS University Bhubaneshwar India Department of Mechanical Engineering NIT Rourkela India Department of Mechanical Engineering KL University Guntur India

This paper presents the rigorous study of mobile robot navigation techniques used so *** step by step investigations of classical and reactive approaches are made here to understand the development of path planning strategies in various environmental conditions and to identify research *** classical approaches such as cell decomposition(CD),roadmap approach(RA),artificial potential field(APF);reactive approaches such as genetic algorithm(GA),fuzzy logic(Fl),neural network(nn),firefly algorithm(FA),particle swarm optimization(PSO),ant colony optimization(ACO),bacterial foraging optimization(BFO),artificial bee colony(ABC),cuckoo search(CS),shuffled frog leaping algorithm(SFlA)and other miscellaneous algorithms(OMA)are considered for *** navigation over static and dynamic condition is analyzed(for single and multiple robot systems)and it has been observed that the reactive approaches are more robust and perform well in all terrain when compared to classical *** is also observed that the reactive approaches are used to improve the performance of the classical approaches as a hybrid ***,reactive approaches are more popular and widely used for path planning of mobile *** paper concludes with tabular data and charts comparing the frequency of individual navigational strategies which can be used for specific application in robotics.

关键词： Mobile robot navigation Path planning Classical approaches Reactive approaches Artificial intelligence

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Active learning of deep surrogates for PDEs:application to metasurface design

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npj Computational Materials 2020年第1期6卷 312-318页

作者： Raphaël Pestourie Youssef Mroueh Thanh V.Nguyen Payel Das Steven G.Johnson Department of Mathematics Massachusetts Institute of Technology77 Massachusetts AveCambridgeMA 02139USA IBM Research AI IBM Thomas J Watson Research CenterYorktown HeightsYorktownNY 10598USA MIT-IBM Watson AI lab CambridgeMA 02139USA Iowa State University AmesIA 50011USA

Surrogate models for partial differential equations are widely used in the design of metamaterials to rapidly evaluate the behavior of composable ***,the training cost of accurate surrogates by machine learning can rapidly increase with the number of *** photonic-device models,we find that this training becomes especially challenging as design regions grow larger than the optical *** present an active-learning algorithm that reduces the number of simulations required by more than an order of magnitude for an nn surrogate model of optical-surface components compared to uniform random *** show that the surrogate evaluation is over two orders of magnitude faster than a direct solve,and we demonstrate how this can be exploited to accelerate large-scale engineering optimization.

关键词： optimization surrogate faster

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Relativistic domain-wall dynamics in van der Waals antiferromagnet MnPS_(3)

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npj Computational Materials 2022年第1期8卷 27-35页

作者： Ignacio M.Alliati Richard F.l.Evans Kostya S.Novoselov Elton J.G.Santos School of Mathematics and Physics Queen’s University BelfastBelfastBT71NNUK Department of Physics The University of YorkYorkYO105DDUK Institute for Functional Intelligent Materials National University of SingaporeSingapore117544Singapore Institute for Condensed Matter Physics and Complex Systems School of Physics and AstronomyThe University of EdinburghEdinburghEH93FDUK Higgs Centre for Theoretical Physics The University of EdinburghEdinburghEH93FDUK

The discovery of two-dimensional(2D)magnetic van der Waals(vdW)materials has flourished an endeavor for fundamental problems as well as potential applications in computing,sensing and storage *** particular interest are antiferromagnets,which due to their intrinsic exchange coupling show several advantages in relation to ferromagnets such as robustness against external magnetic *** we show that,despite of this cornerstone,the magnetic domains of recently discovered 2D vdW MnPS_(3)antiferromagnet can be controlled via magnetic fields and electric *** achieve ultrafast domain-wall dynamics with velocities up to~3000 m s^(−1)within a relativistic *** contraction and emission of spin-waves in the terahertz gap are observed with dependence on the edge termination of the *** results indicate that the implementation of 2D antiferromagnets in real applications can be further controlled through edge engineering which sets functional characteristics for ultrathin device platforms with relativistic features.

关键词： relativistic dynamics antiferromagnet

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Neural Network Based Adaptive Backstepping Tracking Control for Accommodation Vessel

Neural Network Based Adaptive Backstepping Tracking Control ...

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第36届中国控制会议

作者： Guoxing Wen C.l.Philip Chen Ning Zhou Zhao Xu Department of mathematics Binzhou University Department of Computer and Information Science Faculty of Science and TechnologyUniversity of Macau Dalian Maritime University College of Computer and Information Sciences Fujian Agriculture and Forestry University School of Electronics and Information Northwestern Polytechnical University

ISBN: (纸本)9781538629185

Combined with the backstepping technique,a neural network(nn)-based adaptive tracking control scheme is proposed for the Accommodation Vessel(AV).The control objective is to steer AV following the trajectory of Floating Production Storage and Offloading(FPSO) and keeping the desired distance with FPSO so that the smooth gangway operation can be *** order to fulfill the control task,backstepping is used to achieve the tracking of trajectory;adaptive neural network is used to approximate the unknown nonlinear dynamic of AV for controller ***,it is proven that the proposed control approach can guarantee AV following to *** simulation results further demonstrate effectiveness of the proposed method.

关键词： Adaptive tracking control Backstepping Neural network Accommodation Vessel

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Biquadratic exchange interactions in two-dimensional magnets

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npj Computational Materials 2020年第1期6卷 424-434页

作者： Alexey Kartsev Mathias Augustin Richard F.l.Evans Kostya S.Novoselov Elton J.G.Santos School of Mathematics and Physics Queen’s UniversityBelfast BT71NNUK Department of Physics The University of YorkYork YO105DDUK Department of Material Science&Engineering National University of SingaporeBlock EA9 Engineering Drive 1Singapore 117575Singapore Chongqing 2D Materials Institute Liangjiang New AreaChongqing 400714China Institute for Condensed Matter Physics and Complex Systems School of Physics and AstronomyThe University of EdinburghEdinburgh EH93FDUK

Magnetism in recently discovered van der Waals materials has opened several avenues in the study of fundamental spin interactions in truly two-dimensions.A paramount question is what effect higher-order interactions beyond bilinear Heisenberg exchange have on the magnetic properties of few-atom thick *** we demonstrate that biquadratic exchange interactions,which is the simplest and most natural form of non-Heisenberg coupling,assume a key role in the magnetic properties of layered *** a combination of nonperturbative analytical techniques,non-collinear first-principles methods and classical Monte Carlo calculations that incorporate higher-order exchange,we show that several quantities including magnetic anisotropies,spin-wave gaps and topological spin-excitations are intrinsically renormalized leading to further thermal stability of the layers.

关键词： exchange quadratic magnets

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糖构型讨论

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四川农业大学学报 1988年第3期 201-205页

作者：戴子浠四川农业大学基础部

关于糖的构型,目前仍有许多书面表达方式和不同见解。本文作者认为 1、Hudson的建议与糖构型的书写形式,虽然不能肯定完全一致,但该建议可作为经验规则来处理D、l、α、β及比旋光度之间的关系。这种关系,本文作了归纳。 2、D系糖构型... 详细信息

关于糖的构型,目前仍有许多书面表达方式和不同见解。本文作者认为 1、Hudson的建议与糖构型的书写形式,虽然不能肯定完全一致,但该建议可作为经验规则来处理D、l、α、β及比旋光度之间的关系。这种关系,本文作了归纳。 2、D系糖构型的书面判断,可以只看半缩醛羟基的环上位置就能迅速识别。 3、建议l系糖的链式与环式书写一律使用竖直镜面投影,即可对其构型一目了然,避免混乱。

关键词：构象[34AB] 糖[34H] 形式半缩醛羟基异头体比旋光度

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基于机器学习方法的丙型肝炎病毒非结构蛋白5B聚合酶抑制剂活性预测(英文)

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物理化学学报 2011年第6期27卷 1407-1416页

作者：吕巍薛英山东农业大学生命科学学院作物生物学国家重点实验室山东泰安271018 四川大学化学学院教育部绿色化学与技术重点实验室成都610064 四川大学生物治疗国家重点实验室成都610041

在丙型肝炎病毒(HCV)的基因复制和蛋白质成熟的过程中,非结构蛋白5B(NS5B)作为RNA依赖的RNA聚合酶起到了重要的作用.抑制NS5B聚合酶可以阻止丙型肝炎病毒的RNA复制,因此成为一种治疗丙型肝炎的有效方法.通过计算机方法进行虚拟筛选和预... 详细信息

在丙型肝炎病毒(HCV)的基因复制和蛋白质成熟的过程中,非结构蛋白5B(NS5B)作为RNA依赖的RNA聚合酶起到了重要的作用.抑制NS5B聚合酶可以阻止丙型肝炎病毒的RNA复制,因此成为一种治疗丙型肝炎的有效方法.通过计算机方法进行虚拟筛选和预测NS5B聚合酶抑制剂已经变得越来越重要.本文主要采用机器学习方法(支持向量机(SVM)、k-最近相邻法(k-nn)和C4.5决策树(C4.5DT))对已知的丙型肝炎病毒NS5B蛋白酶抑制剂与非抑制剂建立分类预测模型.1248个结构多样性化合物(552个NS5B抑制剂与696个非NS5B抑制剂)被用于测试分类预测系统,并用递归变量消除法选择与NS5B抑制剂相关的性质描述符以提高预测精度.独立验证集的总预测精度为84.1%-85.0%,NS5B抑制剂的预测精度为81.4%-91.7%,非NS5B抑制剂的预测精度为78.2%-87.2%.其中支持向量机给出最好的NS5B抑制剂预测精度(91.7%);C4.5决策树给出最好的非NS5B抑制剂预测精度(87.2%);k-最近相邻法给出最好的总预测精度(85.0%).研究表明机器学习方法可以有效预测未知数据集中潜在的NS5B抑制剂,并有助于发现与其相关的分子描述符.

关键词：机器学习方法分子描述符递归变量消除法支持向量机丙型肝炎病毒

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Effects of ice massage of the head and spine on heart rate variability in healthy volunteers

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Journal of Integrative Medicine 2016年第4期14卷 306-310页

作者： A. Mooventhan l. Nivethitha Sri Dharmasthala Manjunatheshwara College of Naturopathy and Yogic Sciences and Hospital Ujire-574240 Karnataka India Swami Vivekananda Yoga Anusandhana Samsthana University Bengaluru-560019 Karnataka India

OBJECTIVE： Ice massage （IM） is one of the treatment procedures used in hydrotherapy. Though its various physiological/therapeutic effects have been reported, effects of IM of the head and spine on heart rate variability （HRV） have not been studied. Thus, this study evaluated the effects of IM of the head and spine on HRV in healthy volunteers.METHODS： Thirty subjects were randomly divided into 3 sessions：（1） IM, （2） tap water massage （TWM） and （3） prone rest （PR）. Heart rate （HR） and HRV were assessed before and after each intervention session.RESUlTS： A significant increase in the mean of the intervals between adjacent QRS complexes or the instantaneous HR （RRI）, square root of mean of sum of squares of differences between adjacent normal to normal （nn） intervals （RMSSD）, number of interval differences of successive nn intervals greater than 50 milliseconds （nn50）, proportion derived by dividing nn50 by total number of nn intervals along with significant reduction in HR after IM session; significant increase in RRI along with significant reduction in HR after TWM, and a significant increase only in RMSSD after PR were observed. However, there was no significant difference between the sessions.CONClUSION： Results of this study suggest that 20 min of IM of the head and spine is effective in reducing HR and improving HRV through vagal dominance in healthy volunteers.

关键词： heart rate variability hydrotherapy massage therapy

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Optimization of Electrocardiogram Classification Using Dipper Throated Algorithm and Differential Evolution

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Computers, Materials & Continua 2023年第2期74卷 2379-2395页

作者： Doaa Sami Khafaga El-Sayed M.El-kenawy Faten Khalid Karim Sameer Alshetewi Abdelhameed Ibrahim Abdelaziz A.Abdelhamid D.l.Elsheweikh Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Communications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt General Information Technology Department Ministry of DefenseThe Executive AffairsExcellence Services DirectorateRiyadh11564Saudi Arabia Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia Department of Computer Science Faculty of Specific EducationMansoura UniversityEgypt

Electrocardiogram(ECG)signal is a measure of the heart’s electrical ***,ECG detection and classification have benefited from the use of computer-aided systems by *** goal of this paper is to improve the accuracy of ECG classification by combining the Dipper Throated Optimization(DTO)and Differential Evolution Algorithm(DEA)into a unified algorithm to optimize the hyperparameters of neural network(nn)for boosting the ECG classification *** addition,we proposed a new feature selection method for selecting the significant feature that can improve the overall *** prove the superiority of the proposed approach,several experimentswere conducted to compare the results achieved by the proposed approach and other competing ***,statistical analysis is performed to study the significance and stability of the proposed approach using Wilcoxon and ANOVA *** results confirmed the superiority and effectiveness of the proposed *** classification accuracy achieved by the proposed approach is(99.98%).

关键词： Electrocardiogram differential evolution algorithm dipper throated optimization neural networks

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