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Statistical analysis on strain-rate effects during serrations in a Zr-based bulk metallic glass

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Journal of Iron and Steel Research International 2017年第4期24卷 455-461页

作者： Bo Yuan jiao-jiao li Jun-wei Qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

By means of statistical analysis,the deformation mechanisms taking place in elastic loading and plastic shearing stages during serrated flows on the stress-strain curves for bulk metallic glasses were studied *** serration number presented a linear increasing tendency with the decrease of applied strain rates due to the reduction of free *** excellent plastic deformation was illustrated from the influences of structure arrangement with activation *** using mean-field theory（MFT）,maximum elastic-energy density at different strain rates could be predicted by MFT besides maximum stress drops during *** results were helpful for understanding the serrated flow behavior or designing decent schemes to improve the plasticity of bulk metallic glasses at room temperature.

关键词： Bulk metallic glass Shear band Mean-field theory Serration

Time-varying output feedback H∞control for switched systems based on mixed switching

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Journal of Control and Decision 2022年第3期9卷 364-371页

作者： jiao li College of Science Dalian Minzu UniversityDalianPeople’s Republic of China

This article investigates time-varying dynamic output feedbackH∞control problem for discretetime switched systems by using a time-varying Lyapunov *** rule that depends on available information provided by measured output and time simultaneously is designed for the system with all unstable *** for l2-gain performance and time-varying controller synthesis are obtained under this switching *** provides a more general framework of analyzing discrete-time switched linear systems as it contains the min-switching as special cases when dwell time is not ***,an example shows the effectiveness of the proposed method.

关键词： Switched systems switching rule mixed switching time-varying output feedback H∞control

Decision-making approach by employing grey incidence analysis and group negotiation

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Journal of Systems Engineering and Electronics 2019年第4期30卷 760-769页

作者： liU Yong li jiao ZHANG Renshi School of Business Jiangnan University

For the problems of the consistency ranking of the group decision-making scheme,from the view of group negotiation and system coordination,the grey incidence analysis and Nash bargaining model are used to establish a consistency group decision-making ***,the concepts of the consensus partial decision-making program and the consensus overall ideal decision-making program are defined,and then a multi-object optimization model is constructed based on the satisfaction maximization of group negotiation and deviation minimization of system coordination to determine the consensus partial decision-making program and the consensus overall ideal decision-making ***,the grey incidence analysis is exploited to measure the close degrees between ***,a real case of the online product evaluation verifies the validity and rationality of the proposed model.

关键词： group decision-making group negotiation system coordination grey incidence analysis

Ethical literary Criticism and Overseas Promotion of Chinese Academics

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学术界 2018年第6期 246-256页

作者： li jiao Tianping College Suzhou University of Science and Technology Suzhou Jiangsu 215000

As a new method of literary criticism raised by Chinese scholars,ethical literary criticism has created a theoretical system with Chinese characteristics and become the successful"going global"model of Chinese academics by standing on the Chinese context and adhering to the spirit of not forgetting the origin,absorbing the foreign,and facing the future through more than10 years of advocacy and *** paper analyzes and summarizes the inheritance,nationality,integration and innovation of the theory of literary ethical criticism on the basis of combing the development history of ethical literary criticism at home and abroad,and then analyzes four important reasons why ethical literary criticism can successfully represent the"going global"of Chinese *** paper also discusses the current situation,problems,solutions,trend and future of ethical literary criticism,and points out that ethical literary criticism provides model and reference for realizing the grand blueprint of the"going global"of Chinese academics.

关键词：中国学者文学道德海外上下文

Modeling of grain size in isothermal compression of Ti-6Al-4V alloy using fuzzy neural network

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Rare Metals 2011年第6期30卷 555-564页

作者： LUO jiao li Miaoquan School of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

Isothermal compression of Ti-6Al-4V alloy was conducted in the deformation temperature range of 1093-1303 K, the strain rates of 0.001, 0.01, 0.1, 1.0, and 10.0 s-1, and the height reductions of 20%-60% with an interval of 10%. After compression, the effect of the processing parameters including deformation temperature, strain rate, and height reduction on the flow stress and the microstructure was investigated. The grain size of primary a phase was measured using an OLYMPUS PMG3 microscope with the quantitative metallography SISC IAS V8.0 image analysis software. A model of grain size in isothermal compression of Ti-6A1-4V alloy was developed using fuzzy neural net- work （FNN） with back-propagation （BP） learning algorithm. The maximum difference and the average difference between the predicted and the experimental grain sizes of primary a phase are 13.31% and 7.62% for the sampled data, and 16.48% and 6.97% for the non-sampled data, respectively. It can be concluded that the present model with high prediction precision can be used to predict the grain size in isothermal compression of Ti-6Al-4V alloy.

关键词： titanium alloy isothermal compression grain size fuzzy neural network

Serration Behavior in Zr-Cu-Al Glass-forming Systems

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Journal of Iron and Steel Research International 2016年第1期23卷 42-47页

作者： Zhong WANG jiao-jiao li li-wei REN Yong ZHANG Jun-wei QIAO Bao-cheng WANG Laboratory of Applied Physics and Mechanics of Advanced Materials College of Materials Science and EngineeringTaiyuan University of Technology State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

The metallic glass matrix composites（MGMCs）and bulk metallic glasses（BMGs）were studied by statistical analysis during plastic deformation at the strain rates of 2×10^-2,2×10^-3,and 2×10^-4 s^-1,*** serration events occur in both MGMCs and BMGs during compression tests at the strain rate of 2×10^-2 s^-*** deformed at the strain rate of 2×10^-3 s^-1,the BMG displays a larger plasticity,which is due to the larger serration events followed by a series of small serrations caused by the continuous movement of free *** amplitudes and elastic-energy densities increase with increasing the strain rates owing to many serrations in *** is deduced that the Young′s modulus decreases from the normalized stress drop and fluctuations are observed on stressstrain curves,which is attributed to a lower coefficient according to the stick-slip model.

关键词： bulk metallic glass metallic glass matrix composite serration shear band

Fast implementation of kernel simplex volume analysis based on modified Cholesky factorization for endmember extraction

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 250-257页

作者： Jing li Xiao-run li li-jiao WANG liao-ying ZHAO College of Electrical Engineering Zhejiang University Institute of Computer Application Technology Hangzhou Dianzi University

Endmember extraction is a key step in the hyperspectral image analysis process. The kernel new simplex growing algorithm （KNSGA）, recently developed as a nonlinear alternative to the simplex growing algorithm （SGA）, has proven a promising endmember extraction technique. However, KNSGA still suffers from two issues limiting its application. First, its random initialization leads to inconsistency in final results; second, excessive computation is caused by the iterations of a simplex volume calculation. To solve the first issue, the spatial pixel purity index （SPPI） method is used in this study to extract the first endrnember, eliminating the initialization dependence. A novel approach tackles the second issue by initially using a modified Cholesky fac- torization to decompose the volume matrix into triangular matrices, in order to avoid directly computing the determinant tauto- logically in the simplex volume formula. Theoretical analysis and experiments on both simulated and real spectral data demonstrate that the proposed algorithm significantly reduces computational complexity, and runs faster than the original algorithm.

关键词： Endmember extraction Modified Cholesky factorization Spatial pixel purity index (SPPI) New simplex growingalgorithm (NSGA) Kernel new simplex growing algorithm (KNSGA)

Convenient Synthesis of Two Novel Oxazolidines and Primary Research on their Biological Activities

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Chinese Chemical Letters 2006年第7期17卷 891-894页

作者： Ying jiao li Fei YE College of Science Northeast Agricultural University Harbin 150030

Two novel N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method in good yields. The compounds were Characterized by IR, 1^H NMR and elemental analysis. The preliminary biological tes... 详细信息

关键词： Herbicide safener oxazolidines biological activity.

A parallel scheduling algorithm for reinforcement learning in large state space

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Frontiers of Computer Science 2012年第6期6卷 631-646页

作者： Quan liU Xudong YANG ling JING Jin li jiao li Institute of Computer Science and Technology Soochow UniversitySuzhou 215006China Department of Computer Science and Technology Nanjing UniversityNanjing 210093China Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education Jilin UniversityChangchun 130012China

The main challenge in the area of reinforcement learning is scaling up to larger and more complex problems. Aiming at the scaling problem of reinforcement learning, a scalable reinforcement learning method, DCS-SRL, is proposed on the basis of divide-and-conquer strategy, and its convergence is proved. In this method, the learning problem in large state space or continuous state space is decomposed into multiple smaller subproblems. Given a specific learning algorithm, each subproblem can be solved independently with limited available resources. In the end, component solutions can be recombined to obtain the desired result. To ad- dress the question of prioritizing subproblems in the scheduler, a weighted priority scheduling algorithm is proposed. This scheduling algorithm ensures that computation is focused on regions of the problem space which are expected to be maximally productive. To expedite the learning process, a new parallel method, called DCS-SPRL, is derived from combining DCS-SRL with a parallel scheduling architecture. In the DCS-SPRL method, the subproblems will be distributed among processors that have the capacity to work in parallel. The experimental results show that learning based on DCS-SPRL has fast convergence speed and good scalability.

关键词： divide-and-conquer strategy parallel schedule scalability large state space continuous state space