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Indices and Stability of the Lagrangian System on Riemannian Manifold

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Acta Mathematica Sinica,English Series 2021年第4期37卷 565-580页

作者： Gao sheng ZHU School of Mathematics Tianjin UniversityTianjin 300072P.R.China

In this paper,let m≥1 be an integer,M be an m-dimensional compact Riemannian *** the linearized Poincare map of the Lagrangian system at critical point x d/dt L_(q)(t,x,x)−L_(p)(t,x,x)=0 is explicitly given,then we prove that Morse index and Maslov-type index of x are well defined whether the manifold M is orientable or not via the parallel transport method which makes no appeal to unitary trivialization and establish the relation of Morse index and Maslov-type index,finally derive a criterion for the instability of critical point and orientation of M and obtain the formula for two Maslov-type indices.

关键词： Nonorientable spectral flow Morse index Maslov-type indices Lagrangian system Hamiltonian system

Friction and wear properties of N+ ion implanted nylon 1010

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 274-277页

作者： XIONG Dang-sheng Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China

The PA1010 was implanted with 450 keV N+ ions to three doses of 5× 1014 cm-2 , 2.5× 1015 cm-2 and 1.25 × 1016 cm-2. The friction and wear behaviors of the ion implanted PA1010 disks rubbing with two ceramic (ZrO2 and Si3N4) balls were studied using a pin-on-disk tribometer under dry friction. The results shows that the wear resistance of PA1010 is increased with the increasing implantation doses. The adhesion, plastic deformation and plow groove are wearing mechanisms for un-implanted PA1010, while abrasive wear for implanted PA1010.

关键词： ion implanted PA1010 tribological properties

A prototype of quantum von Neumann architecture

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Communications in Theoretical Physics 2022年第9期74卷 49-63页

作者： Dong-sheng Wang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

A modern computer system,based on the von Neumann architecture,is a complicated system with several interactive modular *** requires a thorough understanding of the physics of information storage,processing,protection,readout,*** computing,as the most generic usage of quantum information,follows a hybrid architecture so far,namely,quantum algorithms are stored and controlled classically,and mainly the executions of them are quantum,leading to the so-called quantum processing *** a quantum-classical hybrid is constrained by its classical ingredients,and cannot reveal the computational power of a fully quantum computer system as conceived from the beginning of the ***,the nature of quantum information has been further recognized,such as the no-programming and no-control theorems,and the unifying understandings of quantum algorithms and computing *** a result,in this work,we propose a model of a universal quantum computer system,the quantum version of the von Neumann *** uses ebits(*** states)as elements of the quantum memory unit,and qubits as elements of the quantum control unit and processing *** a digital quantum system,its global configurations can be viewed as tensor-network *** universality is proved by the capability to execute quantum algorithms based on a program composition scheme via a universal quantum gate *** is also protected by the uncertainty principle,the fundamental law of quantum information,making it quantum-secure and distinct from the classical *** particular,we introduce a few variants of quantum circuits,including the tailed,nested,and topological ones,to characterize the roles of quantum memory and control,which could also be of independent interest in other *** all,our primary study demonstrates the manifold power of quantum information and paves the way for the creation of quantum computer systems in the near future.

关键词： quantum computation quantum channel von Neumann architecture

Some recent developments in modeling quantile treatment effects

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Applied Mathematics(A Journal of Chinese Universities) 2020年第2期35卷 220-243页

作者： TANG sheng-fang Department of Statistics School of EconomicsXiamen UniversityXiamen 361005China

This paper provides a selective review of the recent developments on econometric/statistical modeling in quantile treatment effects under both selection on observables and on ***,we discuss identification,estimation and inference of quantile treatment effects under the framework of selection on ***,we consider the case where the treatment variable is endogenous or self-selected,for which an instrumental variable method provides a powerful tool to tackle this ***,some extensions are discussed to the data-rich environments,to the regression discontinuity design,and some other approaches to identify quantile treatment effects are also *** particular,some future research works in this area are addressed.

关键词： average treatment effect endogeneity quantile treatment effect regression discontinuity design

Impulse feature extraction method for machinery fault detection using fusion sparse coding and online dictionary learning

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Chinese Journal of Aeronautics 2015年第2期28卷 488-498页

作者： Deng Sen Jing Bo sheng sheng Huang Yifeng Zhou Hongliang Aeronautics and Astronautics Engineering College Air Force Engineering University Unit 94371 of People's Liberation Army

Impulse components in vibration signals are important fault features of complex machines. Sparse coding （SC） algorithm has been introduced as an impulse feature extraction method, but it could not guarantee a satisfactory performance in processing vibration signals with heavy background noises. In this paper, a method based on fusion sparse coding （FSC） and online dictionary learning is proposed to extract impulses efficiently. Firstly, fusion scheme of different sparse coding algorithms is presented to ensure higher reconstruction accuracy. Then, an improved online dictionary learning method using FSC scheme is established to obtain redundant dictionary and it can capture specific features of training samples and reconstruct the sparse approximation of vibration signals. Simulation shows that this method has a good performance in solving sparse coefficients and training redundant dictionary compared with other methods. Lastly, the proposed method is further applied to processing aircraft engine rotor vibration signals. Compared with other feature extraction approaches, our method can extract impulse features accurately and efficiently from heavy noisy vibration signal, which has significant supports for machinery fault detection and diagnosis.

关键词： Dictionary learning Fault detection Impulse feature extraction Information fusion Sparse coding

Optimal Policies for Quantum Markov Decision Processes

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International Journal of Automation and computing 2021年第3期18卷 410-421页

作者： Ming-sheng Ying Yuan Feng sheng-Gang Ying Centre for Quantum Software and Information University of Technology SydneyNSW 2007Australia State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Markov decision process(MDP)offers a general framework for modelling sequential decision making where outcomes are *** particular,it serves as a mathematical framework for reinforcement *** paper introduces an extension of MDP,namely quantum MDP(q MDP),that can serve as a mathematical model of decision making about quantum *** develop dynamic programming algorithms for policy evaluation and finding optimal policies for q MDPs in the case of *** results obtained in this paper provide some useful mathematical tools for reinforcement learning techniques applied to the quantum world.

关键词： Quantum Markov decision processes quantum machine learning reinforcement learning dynamic programming decision making

On the Number of Irreducible Characters in a 3-block with a Minimal Nonabelian Defect Group

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Acta Mathematica Sinica,English Series 2017年第9期33卷 1267-1274页

作者： sheng YANG sheng GAO Chong Bin XU Department of Mathematics Wenzhou University Department of Mathematics Hefei University of Technology

Let B be a 3-block of a finite group G with a defect group D. In this paper, we are mainly concerned with the number of characters in a particular block, so we shall use Isaacs＇ approach to block structure. We consider the block B of a group G as a union of two sets, namely a set of irreducible ordinary characters of G having cardinality k（B） and a set of irreducible Brauer characters of G having cardinality l（B）. We calculate k（B） and l（B） provided that D is normal in G and D = （x, y, z｜x3n=y3m = z3 = [x, z] = [y, z] = 1, [x, y] = z）（n 〉 m 〉 2）.

关键词： Characters blocks defect groups inertial groups

Self-corrosion, electrochemical and discharge behavior of commercial purity Al anode via Mn modification in Al-air battery

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Rare Metals 2021年第12期40卷 3501-3511页

作者： Guo-sheng Peng Jun Huang Yi-Cheng Gu Guang-sheng Song School of Materials Science and Engineering Anhui University of TechnologyMa’anshan 243002China Key Laboratory of Green Manufacturing and Surface Technology of Advanced Metal Materials Ministry of EducationAnhui University of TechnologyMa'anshan 243002China

The self-corrosion, electrochemical and discharge behavior of commercial purity Al anode via Mn modification in Al-air battery was studied by the hydrogen evolution, weight loss, electrical conductivity, electrochemical and discharge tests. Results show that the synergetic effects of the dissolved Mn and Mn-modifying Al_(3)Fe intermetallic decrease the weight loss and inhibit the hydrogen evolution of commercial purity Al in Na OH solution when minor Mn is introduced. However, more Mn addition leads to the formation of Al_6Mn intermetallic,which has little effect on the weight loss, but accelerates the hydrogen evolution. Mn introduction plays a positive role in activating Al anodes, resulting in a decrease in the anodic polarization and an increase in the discharge voltage. Among all the commercial purity Al-x Mn anodes, 0.1 wt% Mn addition exhibits the best discharge efficiency for Al-air battery.

关键词： Commercial purity Al Mn addition Corrosion Electrochemical activity Discharge behavior

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西兰花苗中萝卜硫素合成的调控手段研究进展

食品科学 2025年第1期46卷 210-217页

作者：李翠方胜赵忠良刘海杰中国农业大学食品科学与营养工程学院北京100083 江苏新希望生态科技有限公司江苏徐州221150

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生... 详细信息

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生长阶段采用不同处理手段对SFN及其合成相关因子含量的影响,并对其作用机理进行总结分析,最后提出目前还存在的问题及对未来研究方向的展望,为提高植物源食品功能性的相关研究提供一定参考。

关键词：西兰花苗硫代葡萄糖苷萝卜硫素生成机理调控