检索结果-南通市图书馆

Extension of Noether's theorem in PT-symmetry systems and its experimental demonstration in an optical setup

Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 13-27页

作者： Qi-Cheng Wu Jun-Long Zhao Yu-Liang Fang Yu Zhang Dong-Xu Chen Chui-Ping Yang Franco Nori Quantum Information Research center Shangrao Normal UniversityShangrao 334001China School of Physics Nanjing UniversityNanjing 210093China Department of Physics Hangzhou Normal UniversityHangzhou 311121China Theoretical Quantum Physics Laboratory RIKENWako-shiSaitama 351-0198Japan riken center for Quantum Computing RIKENWako-shiSaitama 351-0198Japan Physics Department The University of MichiganAnn Arbor 48109-1040USA

Noether’s theorem is one of the fundamental laws in physics,relating the symmetry of a physical system to its constant of motion and conservation *** the other hand,there exist a variety of non-Hermitian parity-time(PT)-symmetric systems,which exhibit novel quantum properties and have attracted increasing *** this work,we extend Noether’s theorem to a class of significant PT-symmetry systems for which the eigenvalues of the PT-symmetry Hamiltonian HPTchange from purely real numbers to purely imaginary numbers,and introduce a generalized expectation value of an operator based on biorthogonal quantum *** find that the generalized expectation value of a time-independent operator is a constant of motion when the operator presents a standard symmetry in the PT-symmetry unbroken regime,or a chiral symmetry in the PT-symmetry broken *** addition,we experimentally investigate the extended Noether’s theorem in PT-symmetry single-qubit and two-qubit systems using an optical *** experiment demonstrates the existence of the constant of motion and reveals how this constant of motion can be used to judge whether the PT-symmetry of a system is ***,a novel phenomenon of masking quantum information is first observed in a PT-symmetry two-qubit *** study not only contributes to full understanding of the relation between symmetry and conservation law in PT-symmetry physics,but also has potential applications in quantum information theory and quantum communication protocols.

关键词： Noether’s theorem PT-symmetry systems chiral symmetry optical setup

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimization of Sentiment Analysis Using Teaching-Learning Based Algorithm

引用

Computers, Materials & Continua 2021年第11期69卷 1783-1799页

作者： Abdullah Muhammad Salwani Abdullah Nor Samsiah Sani center for Artificial intelligence Technology Faculty of Information Science&TechnologyUniversiti KebangsaanKajang43000Malaysia

Feature selection and sentiment analysis are two common studies that are currently being conducted;consistent with the advancements in computing and growing the use of social *** dimensional or large feature sets is a key issue in sentiment analysis as it can decrease the accuracy of sentiment classification and make it difficult to obtain the optimal subset of the ***,most reviews from social media carry a lot of noise and irrelevant ***,this study proposes a new text-feature selection method that uses a combination of rough set theory(RST)and teaching-learning based optimization(TLBO),which is known as *** framework to develop the proposed RSTLBO includes numerous stages:(1)acquiring the standard datasets(user reviews of six major ***)which are used to validate search result feature selection methods,(2)preprocessing of the dataset using text processing *** involves applying text processing methods from natural language processing techniques,combined with linguistic processing techniques to produce high classification results,(3)employing the RSTLBO method,and(4)using the selected features from the previous process for sentiment classification using the Support Vector Machine(SVM)*** show an improvement in sentiment analysis when combining natural language processing with linguistic processing for text *** importantly,the proposed RSTLBO feature selection algorithm is able to produce an improved sentiment analysis.

关键词： Feature selection sentiment analysis rough set theory teachinglearning optimization algorithms text processing

来源：

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

Higher order asymptotic behaviour of partial maxima of random sample from generalized Maxwell distribution under power normalization

引用

Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 177-187页

作者： HUANG Jian-wen WANG Jian-jun School of Mathematics and Statistics Southwest University Research center for Artificial intelligence & Education Big Data Southwest University

In this article, the higher order asymptotic expansions of cumulative distribution function and probability density function of extremes for generalized Maxwell distribution are established under nonlinear normalization. As corollaries, the convergence rates of the distribu- tion and density of maximum are obtained under nonlinear normalization.

关键词： higher order expansion extreme generalized Maxwell distribution nonlinear normalization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Label-free trace detection of bio-molecules by liquid-interface assisted surface-enhanced Raman scattering using a microfluidic chip

引用

Opto-Electronic Advances 2022年第10期5卷 12-21页

作者： Shi Bai Xueli Ren Kotaro Obata Yoshihiro Ito Koji Sugioka advanced Laser Processing Research Team RIKEN Center for Advanced Photonics2-1 HirosawaWakoSaitama 351-0198Japan Nano Medical Engineering Laboratory RIKEN Cluster for Pioneering Research2-1 HirosawaWakoSaitama 351-0198Japan

Surface-enhanced Raman scattering(SERS),owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals,is recently attracting much attention to be used for biotechnology,such as cell imaging and tumor *** the other hand,the trace detection of bio-molecules with large molecular weight is still challenging because the troublesome treatment of SERS substrate using coupling or cross-linking agents is *** this paper,we apply liquid interface assisted SERS(LI-SERS)method,which provides unique features of collection and self-immobilization of analyte molecules on the SERS substrate,to realize the label-free trace detection of bio-molecules with detection limits of pM~***,deoxyribonucleic acid(DNA)discrimination and quantitative detection ofβ-Amyloid(Aβ)in trace-concentration are demonstrated to illustrate the ultrahigh sensitivity and versatility of the LI-SERS *** results suggest LI-SERS is promising for the early-stage diagnosis of diseases such as virus infection and Alzheimer's disease.

关键词： femtosecond laser processing LI-SERS microfluidic chip DNA β-Amyloid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of a novel autonomous lower extremity exoskeleton robot for walking assistance

引用

Frontiers of Information Technology & Electronic Engineering 2019年第3期20卷 318-329页

作者： Yong HE Nan LI Chao WANG Lin-qing XIA Xu YONG Xin-yu WU Guangdong Provincial Key Laboratory of Robotics and Intelligent System Shenzhen Institute of Advanced Technology Chinese Academy of Sciences CAS Key Laboratory of Human-Machine intelligence-Synergy Systems Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen College of advanced Technology University of Chinese Academy of Sciences Department of Mechanical Engineering and Intelligent Systems the University of Electro-Communications

Today, exoskeletons are widely applied to provide walking assistance for patients with lower limb motor incapacity. Most existing exoskeletons are under-actuated, resulting in a series of problems, e.g., interference and unnatural gait during walking. In this study, we propose a novel intelligent autonomous lower extremity exoskeleton(Auto-LEE), aiming at improving the user experience of wearable walking aids and extending their application *** traditional exoskeletons, Auto-LEE has 10 degrees of freedom, and all the joints are actuated independently by direct current motors, which allows the robot to maintain balance in aiding walking without extra *** new exoskeleton is designed and developed with a modular structure concept and multi-modal human-robot interfaces are considered in the control system. To validate the ability of self-balancing bipedal walking, three general algorithms for generating walking patterns are researched, and a preliminary experiment is implemented.

关键词： Lower-limb Exoskeleton Self-balancing Bipedal walking Modular design

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

High-performance Zn-graphite battery based on LiPF6 single-salt electrolyte with high working voltage and long cycling life

引用

Journal of Energy Chemistry 2021年第7期30卷 602-609页

作者： Yong Wang Luojiang Zhang Fan Zhang Xuan Ding Kyungsoo Shin Yongbing Tang Functional Thin Films Research center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of advanced Materials Processing&Mold Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine intelligence-Synergy Systems Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina

Zinc-ion batteries(ZIBs) are promising alternative energy storage devices to lithium-ion batteries owing to the merits of large abundance,high theoretical capacity,and environmental ***,critical challenges including low working voltage(below 2 V),low energy density as well as dendrites formation during long cycling caused by aqueous ZIB systems still hinder their practical ***,a high-voltage Zn-graphite battery(ZGB) based on a non-zinc ion single-salt electrolyte(2.5 M LiPF6 in carbonate solvent) is ***,we surprisingly found that Zn^(2+) is dissolved in the LiPF6 single-salt electrolyte during resting and discharging processes,thus enabling reversible Zn plating/stripping mechanism on the Zn foil anode in the ZGB over the voltage window of 1.0-3.1 *** a result,the ZGB achieves long-term cycling performance with a capacity retention of ~100% for over1200 cycles at 3 C and high Coulombic efficiency of ~100% in 1.0-3.1 V with no dendrites ***,the ZGB exhibits a high working voltage of up to 2.2 V,thus contributing to both high energy density(up to 210 Wh kg^(-1)) and high power density(up to 1013 W kg^(-1)),superior than most reported ZIBs.

关键词： Zinc-ion battery Zn anode Graphite cathode LiPF6 single-salt electrolyte High voltage

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Symmetry-adapted graph neural networks for constructing molecular dynamics force fields

引用

Science China(Physics,Mechanics & Astronomy) 2021年第11期64卷 118-126页

作者： Zun Wang Chong Wang SiBo Zhao ShiQiao Du Yong Xu Bing-Lin Gu WenHui Duan State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Department of Physics Carnegie Mellon UniversityPittsburgh 15213USA Institute for advanced Study Tsinghua UniversityBeijing 100084China Frontier Science center for Quantum Information Beijing 100084China riken center for Emergent Matter Science(CEMS) WakoSaitama 351-0198Japan

Molecular dynamics is a powerful simulation tool to explore material *** realistic material systems are too large to be simulated using first-principles molecular *** molecular dynamics has a lower computational cost but requires accurate force fields to achieve chemical *** this work,we develop a symmetry-adapted graph neural network framework called the molecular dynamics graph neural network(MDGNN)to construct force fields automatically for molecular dynamics simulations for both molecules and *** architecture consistently preserves translation,rotation,and permutation invariance in the *** also propose a new feature engineering method that includes high-order terms of interatomic distances and demonstrate that the MDGNN accurately reproduces the results of both classical and first-principles molecular *** addition,we demonstrate that force fields constructed by the proposed model have good *** MDGNN is thus an efficient and promising option for performing molecular dynamics simulations of large-scale systems with high accuracy.

关键词： graph neural networks molecular dynamics force fields

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Controllable alignment of elongated microorganisms in 3D microspace using electrofluidic devices manufactured by hybrid femtosecond laser microfabrication

引用

Microsystems & Nanoengineering 2017年第1期3卷 396-404页

作者： Jian Xu Hiroyuki Kawano Weiwei Liu Yasutaka Hanada Peixiang Lu Atsushi Miyawaki Katsumi Midorikawa Koji Sugioka riken center for advanced Photonics 2-1 HirosawaWakoSaitama 351-0198Japan Laboratory for Cell Function Dynamics RIKEN Brain Science Institute2-1 HirosawaWakoSaitama 351-0198Japan Wuhan National Laboratory for Optoelectronics and School of Physics Huazhong University of Science and TechnologyWuhan 430074China Laboratory of Optical Information and Technology School of ScienceWuhan Institute of TechnologyWuhan 430073China

This paper presents a simple technique to fabricate new electrofluidic devices for the three-dimensional(3D)manipulation of microorganisms by hybrid subtractive and additive femtosecond(fs)laser microfabrication(fs laser-assisted wet etching of glass followed by water-assisted fs laser modification combined with electroless metal plating).The technique enables the formation of patterned metal electrodes in arbitrary regions in closed glass microfluidic channels,which can spatially and temporally control the direction of electric fields in 3D microfluidic *** fabricated electrofluidic devices were applied to nanoaquariums to demonstrate the 3D electro-orientation of Euglena gracilis(an elongated unicellular microorganism)in microfluidics with high controllability and *** particular,swimming Euglena cells can be oriented along the z-direction(perpendicular to the device surface)using electrodes with square outlines formed at the top and bottom of the channel,which is quite useful for observing the motions of cells parallel to their swimming ***,z-directional electric field control ensured efficient observation of manipulated cells on the front side(45 cells were captured in a minute in an imaging area of~160×120μm),resulting in a reduction of the average time required to capture the images of five Euglena cells swimming continuously along the z-direction by a factor of~43 compared with the case of no electric *** addition,the combination of the electrofluidic devices and dynamic imaging enabled observation of the flagella of Euglena cells,revealing that the swimming direction of each Euglena cell under the electric field application was determined by the initial body angle.

关键词： dynamic imaging electrofluidic devices electro-orientation femtosecond laser microfabrication flagellar motions selective metallization 3D electric fields 3D microfluidics

来源：

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

Automated pipeline for superalloy data by text mining

引用

npj Computational Materials 2022年第1期8卷 58-69页

作者： Weiren Wang Xue Jiang Shaohan Tian Pei Liu Depeng Dang Yanjing Su Turab Lookman Jianxin Xie Beijing advanced Innovation center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083China Collaborative Innovation center of Steel Technology University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Materials Genome Engineering University of Science and Technology BeijingBeijing100083China School of Artificial intelligence Beijing Normal UniversityBeijing100875China AiMaterials Research LLC Santa FeNM87501USA

Data provides a foundation for machine learning,which has accelerated data-driven materials *** scientific literature contains a large amount of high-quality,reliable data,and automatically extracting data from the literature continues to be a *** propose a natural language processing pipeline to capture both chemical composition and property data that allows analysis and prediction of *** 3 h,2531 records with both composition and property are extracted from 14,425 articles,coveringγ′solvus temperature,density,solidus,and liquidus temperatures.A data-driven model forγ′solvus temperature is built to predict unexplored Co-based superalloys with highγ′solvus temperatures within a relative error of 0.81%.We test the predictions via synthesis and characterization of three alloys.A web-based toolkit as an online open-source platform is provided and expected to serve as the basis for a general method to search for targeted materials using data extracted from the literature.

关键词： superalloy property pipeline

来源：

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

Development of a lower limb multi-joint assistance soft exosuit

引用

Science China(Information Sciences) 2020年第7期63卷 116-118页

作者： Xinyu WU Kai FANG Chunjie CHEN Yu ZHANG Guangdong Provincial Key Lab of Robotics and Intelligent System Shenzhen Institutes of Advanced TechnologyChinese Academy of Sciences SIAT Branch Shenzhen Institute of Artificial Intelligence and Robotics for Society Shenzhen College of advanced Technology University of Chinese Academy of Sciences

Dear editor,Great progress has been made in exoskeleton research over the past decades. Exoskeletons of various types have been developed for a range of purposes, predominantly military and clinical [1,2]. Some adopt rigid structures to increase the wearer’s load carriage capacity, while others utilize external power sources to provide the wearer

关键词： Lower-limb Multi-joint assistance Soft exosuit Metabolic cost Ground walking Uphill walking Stairs clilmbing

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：