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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 340-352页

作者： Matheus J.lazo Delfim f.M.Torres Instituto de Matemática Estatística e Física-FURG Center for Research and Development in Mathematics and Applications (CIDMA) Department of MathematicsUniversity of Aveiro

Invariant conditions for conformable fractional problems of the calculus of variations under the presence of external forces in the dynamics are studied. Depending on the type of transformations considered, different necessary conditions of invariance are obtained. As particular cases, we prove fractional versions of Noether's symmetry theorem. Invariant conditions for fractional optimal control problems, using the Hamiltonian formalism, are also investigated. As an example of potential application in Physics, we show that with conformable derivatives it is possible to formulate an Action Principle for particles under frictional forces that is far simpler than the one obtained with classical fractional derivatives.

关键词： Conformable fractional derivative fractional calculus of variations fractional optimal control invariant variational conditions Noether’s theorem

from frequency domain to time domain:performance analysis on cyclic prefixed multi-user single-carrier transmission

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Science china(Information Sciences) 2016年第8期59卷 144-152页

作者： Wei PENG Qing f.ZHOU An HUANG Shaodan MA School of Electronics Information and Communications Huazhong University of Science and Technology School of Computer and Information Hefei University of Technology faculty of Science and Technology University of Macau

This paper analyzes the performance of cyclic prefixed single-carrier transmission under multiuser interference(MUI). for multi-user receivers using single carrier frequency domain adaptive antenna array,we derive the signal to interference plus noise ratio by analyzing the time domain estimated signal after the transformation from frequency domain to time domain. By assuming the MUI follows the Gaussian distribution,we can derive the analytical expression for the bit error rate(BER) performance. The analytical result is verified by the numerical results generated by Monte Carlo method. It is concluded from the analytical results that if the number of receive antennas goes to infinity as assumed in massive multiple input multiple output(MIMO)system, the BER performance will be determined by two ratios: signal to noise ratio as well as the Nr to U ratio, where Nr is the number of receive antennas and U is the number of users.

关键词： single-carrier transmission multi-user interference frequency domain processing MIMO SCfDAAA

Model-based framework for multi-axial real-time hybrid simulation testing

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 671-691页

作者： Gaston A.fermandois Billie f.Spencer,Jr. Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit significant dynamic coupling of the actuators and suffer from time lags that are associated with the dynamics of the servo-hydraulic system, as well as control-structure interaction （CSI）. One approach to reducing experimental errors considers a multi-input, multi-output （MIMO） controller design, yielding accurate reference tracking and noise rejection. In this paper, a framework for multi-axial real-time hybrid simulation （maRTHS） testing is presented. The methodology employs a real-time feedback-feedforward controller for multiple actuators commanded in Cartesian coordinates. Kinematic transformations between actuator space and Cartesian space are derived for all six-degrees-of- freedom of the moving platform. Then, a frequency domain identification technique is used to develop an accurate MIMO transfer function of the system. further, a Cartesian-domain model-based feedforward-feedback controller is implemented for time lag compensation and to increase the robustness of the reference tracking for given model uncertainty. The framework is implemented using the 1/5th-scale load and Boundary Condition Box （lBCB） located at the University of Illinois at Urbana- Champaign. To demonstrate the efficacy of the proposed methodology, a single-story frame subjected to earthquake loading is tested. One of the columns in the fraane is represented physically in the laboratory as a cantilevered steel column. for real- time execution, the numerical substructure, kinematic transformations, and controllers are implemented on a digital signal processor. Results show excellent performance of the maRTHS framework when

关键词： real-time hybrid simulation multiple actuators dynamic coupling kinematic transformations model-basedcompensation

Electrochemical studies of Meldola blue-modified bilayer lipid membranes

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chinese Science Bulletin 1997年第3期42卷 203-207页

作者： Ding, l Wang, EK chiNESE ACAD SCI CHANGCHUN INST APPL CHEMELECTROANALYT CHEM LABCHANGCHUN 130022PEOPLES R CHINA

BIlAYER lipid membranes (BlM) have been extensively regarded as a basic structure that forms the matrix of biological membranes. The properties of BlM may be altered by incorporation and modification and can be employed to study many membrane processes. Especially biosensors and bi-molecular electronic devices made by BlM have a wide application. Many kinds of organic dyes are known as biological stains and often used in biology, physiology, pharmacology and medicine. In general, coloring and staining processes involve adsorp-

关键词： Meldola blue bilayer lipid membranes (BlM) electrochemistry.

Brain-machine-brain interfaces as the foundation for the next generation of neuroprostheses

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National Science Review 2022年第10期9卷 8-10页

作者： Miguel A.l.Nicolelis Department of Neurobiology Duke University International Institute of Neuroscience Edmond and lily Safra

Back in 2011,my laboratory at the Duke University Center for Neuroengineering proposed a new variation on the already-classic paradigm known as brain-machine interfaces (BMIs)[1].In a series of experiments [2],we showed that monkeys could not only learn to employ electrical signals from large neuronal ensembles (300-700 neurons)located in the primary motor cortex(M1) to control the movements of an avatar arm and hand—*** a typical BMI paradigm—but that they could also interpret in real time,streams of electrical signals delivered directly to their primary somatosensory cortex (S1) via cortical *** strategy was created to allow these monkeys to perform a tactile discrimination task,without any interference from their physical ***,instead of using their real finger tips to perform such a task,this approach allowed our monkeys to use their brain activity to directly control the movements of’virtual finger tips to scan the texture of a series of virtual *** receiving,via cortical microstimulation,electrical signals directly into their S1 that were proportional to the virtual surface textures of these objects,the monkeys learned to quickly select the correct object that they needed to identify to receive a ***,

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解纤维热酸菌产l-阿拉伯糖异构酶的培养条件优化

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食品工业科技 2009年第4期30卷 153-155,159页

作者：秦啸天江波 chi-Tang Ho 江南大学食品科学与技术国家重点实验室江苏无锡214122 food Science Department Cook College Rutgers UniversityNew BrunswickNJ 08901-8520

解纤维热酸菌SK1.009发酵产生合成塔格糖所需的l-阿拉伯糖异构酶,通过单因素与正交实验优化确定产酶培养基条件。结果表明,发酵最佳条件(g/l):可溶性淀粉8、蛋白胨鱼粉1、l-阿拉伯糖1.5、NH4Cl1、KH2PO41、Na2HPO4·12H2O0.135、MgSO4.7... 详细信息

解纤维热酸菌SK1.009发酵产生合成塔格糖所需的l-阿拉伯糖异构酶,通过单因素与正交实验优化确定产酶培养基条件。结果表明,发酵最佳条件(g/l):可溶性淀粉8、蛋白胨鱼粉1、l-阿拉伯糖1.5、NH4Cl1、KH2PO41、Na2HPO4·12H2O0.135、MgSO4.7H2O0.2、CaCl20.15,发酵初始pH4.5,培养温度55℃,接种量4%,培养时间60h。在该最佳培养基下发酵产生酶活为0.184U/ml。

关键词： l-阿拉伯糖异构酶解纤维热酸菌培养条件优化

A model to explain the angular distribution of J/Ψ and Ψ(2S) decay into ■ and ■

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chinese Physics C 2019年第2期43卷 31-36页

作者： M.Alekseev A.Amoroso R.Baldini ferroli I.Balossino M.Bertani D.Bettoni f.Bianchi J.Chai G.Cibinetto f.Cossio f.De Mori M.Destefanis R.farinelli l.fava G.felici I.Garzia M.Greco l.lavezzi C.leng M.Maggiora A.Mangoni S.Marcello G.Mezzadri S.Pacetti P.Patteri A.Rivetti M.Da Rocha Rolo M.Savrié S.Sosio S.Spataro l.Yan Università di Torino INfN Sezione di Torino INfN laboratori Nazionali di frascati INfN Sezione di ferrara Institute of High Energy Physics Università di ferrara Università del Piemonte Orientale Università di Perugia INfN Sezione di Perugia

BESⅢ data show a particular angular distribution for the decay of J/Ψ and Ψ(2 S) mesons into ■ and Σ~0Σ~0 hyperons: the angular distribution of the decay Ψ(2 S) →Σ~0Σ~0 exhibits an opposite trend with respect to the other three channels: J/Ψ→■, J/Ψ→Σ~0Σ~0 and Ψ(2 S) →■. We define a model to explain the origin of this phenomenon.

关键词： J/ψandψ(2S)hadronic decays effective lagrangian model polarization parameters

A crystal plasticity based approach to establish role of grain size and crystallographic texture in the Tension–Compression yield asymmetry and strain hardening behavior of a Magnesium–Silver–Rare Earth alloy

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Journal of Magnesium and Alloys 2022年第9期10卷 2546-2562页

作者： Sourav Mishra f.Khan S.K.Panigrahi Department of Mechanical Engineering Indian Institute of Technology MadrasChennai 600036Tamil NaduIndia Applied Magnesium Research Group Centre for Materials and Manufacturing for Futuristic MobilityIndian Institute of Technology MadrasChennai 600036Tamil NaduIndia School of Mechanical Engineering Vellore Institute of TechnologyVellore 632014Tamil NaduIndia

Existence of tension–compression yield asymmetry is a serious limitation to the load bearing capablities of Magnesium alloys in a number of light weight structural *** present work is aimed at nullifying the tension to compression asymmetry problem and strain hardening anomalies in a Magnesium–Silver–Rare Earth alloy by engineering different levels of microstructural conditions via friction stir processing and post process *** existence and extent of yield asymmetry ratio in the range of microstructural conditions was experimentally obtained through quasistatic tensile and compression *** yield asymmetry problem was profoundly present in specimens of coarse grained microstructures when compared to their fine grained and ultra fine grained *** impact of the microstructure and associated mechanisms of plasticity on the macroscopic strain hardening behavior was established by Kock–Mecking’s *** plasticity simulations using Viscoplastic Self Consistency approach revealed the consequential role of extension twinning mechanism for the existence of yield asymmetry and anomalies in strain hardening *** was especially dominant with coarsening of grain *** Microscopy and characterization were conducted thoroughly in partially deformed specimens to confirm the predictions of the above *** role of crystallographic texture for inducing the polarity to Tension–Compression yield asymmetry was corroborated.A critical grain size in Magnesium–Silver–Rare earth alloy was hereby established which could nullify influences of extension twinning in yield asymmetry ratio.

关键词： Magnesium silver rare earth alloy friction stir processing Ultrafine-grained microstructure Tension to compression yield strength asymmetry Crystallographic texture Strain hardening Kock mecking plots Visco plastic self consistency

Endoplasmic reticulum stress,autophagy,neuroinflammation,and sigma 1 receptors as contributors to depression and its treatment

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Neural Regeneration Research 2024年第10期19卷 2202-2211页

作者： chika fujii Charles f.Zorumski Yukitoshi Izumi Department of Psychiatry Washington University School of MedicineSt.LouisMOUSA Taylor family Institute for Innovative Psychiatric Research Washington University School of MedicineSt.LouisMOUSA

The etiological factors contributing to depression and other neuropsychiatric disorders are largely undefined. Endoplasmic reticulum stress pathways and autophagy are well-defined mechanisms that play critical functions in recognizing and resolving cellular stress and are possible targets for the pathophysiology and treatment of psychiatric and neurologic illnesses. An increasing number of studies indicate the involvement of endoplasmic reticulum stress and autophagy in the control of neuroinflammation, a contributing factor to multiple neuropsychiatric illnesses. Initial inflammatory triggers induce endoplasmic reticulum stress, leading to neuroinflammatory responses. Subsequently, induction of autophagy by neurosteroids and other signaling pathways that converge on autophagy induction are thought to participate in resolving neuroinflammation. The aim of this review is to summarize our current understanding of the molecular mechanisms governing the induction of endoplasmic reticulum stress, autophagy, and neuroinflammation in the central nervous system. Studies focused on innate immune factors, including neurosteroids with anti-inflammatory roles will be reviewed. In the context of depression, animal models that led to our current understanding of molecular mechanisms underlying depression will be highlighted, including the roles of sigma 1 receptors and pharmacological agents that dampen endoplasmic reticulum stress and associated neuroinflammation.

关键词： allopregnanolone fluvoxamine ketamine neurosteroids postpartum depression quercetin