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Stochastic averaging of quasi integrable and resonant Hamiltonian systems excited by fractional Gaussian noise with Hurst index 1/2

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Acta Mechanica Solida Sinica 2017年第1期30卷 11-19页

作者： q.F.Lü M.L.Deng W.q.Zhu Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsKey Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceZhejiang University

A stochastic averaging method of quasi integrable and resonant Hamiltonian systems under excitation of fractional Gaussian noise （fGn） with the Hurst index 1/2 〈 H 〈 1 is proposed. First, the definition and the basic property of fGn and related fractional Brownian motion （iBm） are briefly introduced. Then, the averaged fractional stochastic differential equations （SDEs） for the first integrals and combinations of angle variables of the associated Hamiltonian systems are derived. The stationary probability density and statistics of the original systems are then obtained approximately by simulating the averaged SDEs numerically. An example is worked out to illustrate the proposed stochastic averaging method. It is shown that the results obtained by using the proposed stochastic averaging method and those from digital simulation of original system agree well.

关键词： quasi integrable and resonant Hamiltonian system Fractional Brownian motion Fractional Gaussian noise Stochastic averaging method Internal resonant

Projective representation of D_(6)group in twisted bilayer graphene

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Chinese Physics B 2021年第7期30卷 1-4页

作者： Noah F.q.Yuan Department of Physics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

Within the framework of continuum model,we study the projective representation of emergent D_(6)point group in twisted bilayer *** then construct tight-binding models of the lowest bands without and with external elec... 详细信息

关键词： twisted bilayer graphene tight-binding model projective representation

Study of magnetic and optical properties of Zn1-xTMxTe(TM = Mn,Fe,Co,Ni) diluted magnetic semiconductors：First principle approach

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Chinese Physics B 2017年第2期26卷 452-460页

作者： q Mahmood M Hassan M A Faridi Department of Physics University of the Punjab Quaid-e-Azam Campus-54590 Lahore Pakistan Centre for High Energy Physics University of the Punjab Lahore Pakistan

We present structural,magnetic and optical characteristics of Zn_（1-x）TM_xTe（TM = Mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） *** optimization of the crystal structures have been done to compare the ferromagnetic（FM） and antiferromagnetic（AFM） ground state energies,to elucidate the ferromagnetic phase stability,which further has been verified through the formation and cohesive ***,the estimated Curie temperatures T_c have demonstrated above room temperature ferromagnetism（RTFM） in Zn_（1-x）TM_xTe（TM =Mn,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that Mn- and Co-doped ZnTe behave as ferromagnetic semiconductors,while half-metallic ferromagnetic behaviors are observed in Fe- and Ni-doped *** presence of ferromagnetism is also demonstrated to be due to both the p-d and s-d hybridizations between the host lattice cations and TM *** calculated band gaps and static real dielectric constants have been observed to vary according to Penn＇s *** evaluated band gaps lie in near visible and ultraviolet regions,which make these materials suitable for various important device applications in optoelectronic and spintronic.

关键词： magnetic semiconductors density functional theory optical and dielectric properties electron density of states and band structure of crystalline solids

TGF-b:the sword,the wand,and the shield of FOXP3^(+)regulatory T cells

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Journal of Molecular Cell Biology 2012年第1期4卷 29-37页

作者： Dat q.Tran Division of Pediatric Research Center Department of PediatricsThe University of Texas Medical School at HoustonHoustonTX 77030USA

Since its rediscovery in the mid-1990s,FOXP31 regulatory T cells(Tregs)have climbed the rank to become commander-in-chief of the immune *** possess diverse power and ability to orchestrate the immune system in time of inflammation and infection as well as in time of harmony and *** be the commander-in-chief,they must be equipped with both offensive and defensive *** review will focus on the function of transforming growth factor-b(TGF-b)as the sword,the wand,and the shield of *** as a sword,this review will begin with a discussion of the evidence that supports how Tregs utilize TGFb to paralyze cell activation and differentiation to suppress immune *** will next provide evidence on how TGF-b from Tregs acts as a wand to convert naıve T cells into iTregs and Th17 to aid in their combat against inflammation and ***,the review will present evidence on the role of TGF-b produced by Tregs in providing a shield to protect and maintain Tregs against apoptosis and destabilization when surrounded by inflammation and constant *** triadic function of TGF-b empowers Tregs with the responsibility and burden to maintain homeostasis,promote immune tolerance,and regulate host defense against foreign pathogens.

关键词： Foxp3 TGF-b LAP LRRC32 GARP Tregs autoimmunity tolerance transplantation

HIGH ACCURACY FOR MIXES FINITE ELEMENT METHODS IN RAVIART-THOMAS ELEMENT

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Journal of Computational Mathematics 1996年第2期14卷 175-182页

作者： Lin, q Pan, JH CHINESE ACAD SCI INST SYST SCIBEIJINGPEOPLES R CHINA UNIV PETR DEPT BASIC SCIBEIJINGPEOPLES R CHINA

This paper deals with Raviart-Thomas element (q(2,1) x q(1,2) - q(1) element). Apart from its global superconvergence property of fourth order, we prove that a postprocessed extrapolation can globally increased the ac... 详细信息

关键词： Math Wang HIGH ACCURACY FOR MIXES FINITE ELEMENT METHODS IN RAVIART-THOMAS ELEMENT

Cross Flow Through a Corrugated Channel With Patterned Slip

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Cross Flow Through a Corrugated Channel With Patterned Slip

Clinical utility of non-invasive tests to predict clinical outcomes in non-alcoholic fatty liver disease

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong Youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： q.Zhou C.O.ng Department of Mechanical Engineering The University of Hong Kong

This work aims to investigate the integrated effects of wall corrugations and slip patterns on the flow in a *** slip length for pressure-driven cross flow through a corrugated channel with patterned wall slip is deduced using the lubrication approximation method on assuming slow variations in the streamwise *** of the effective slip length are numerically obtained for various combinations of phase differences within and between the corrugations and the slip *** particular,effective slip lengths for basic situations(*** only corrugations considered and with only patterned slip considered) are calculated first and summarized to compare with findings of previous *** of this work show that for cross flow the maximum effective slip length appears when the corrugations are in phase and the slip patterns are half-period out of phase;while the minimum value may but not necessarily appear when the corrugations are half-period out of phase and the slip patterns are in *** is also presented showing that,when the corrugations are in phase,changes of the corrugation parameters, such as the corrugation magnitude and the phase difference between the corrugations and the slip pattern will have no effect on the effective slip length.

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Hepatobiliary Surgery and Nutrition 2023年第6期12卷 916-918页

作者： Shi Yan Lee Darren J.H.Tan Wen Hui Lim Cheng Han ng Mark Muthiah Daniel q.Huang Division of Gastroenterology and Hepatology Department of MedicineNational University HospitalSingaporeSingapore Yong Loo Lin School of Medicine National University of SingaporeSingaporeSingapore National University Centre for Organ Transplantation National University Health SystemSingaporeSingapore

Non-alcoholic fatty liver disease(NAFLD)is the leading cause of chronic liver disease,and the fastest-growing cause of hepatocellular carcinoma(HCC)worldwide(1,2).As the number of people with NAFLD is too great to perform surveillance in all,risk-stratification strategies are increasingly important to identify those at the highest risk of decompensation and HCC(3,4).

关键词： Non-alcoholic fatty liver disease(NAFLD) non-invasive tests fibrosis-4(FIB-4) vibration-controlled transient elastography(VCTE) clinical outcomes

Zinc Oxide-Based q-Switched Erbium-Doped Fiber Laser

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Chinese Physics Letters 2017年第4期34卷 43-45页

作者： N.A.Aziz A.A.Latiff M.q.Lokman E.Hanafi S.W.Harun Department of Electrical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia Photonics Research Centre University of Malaya Kuala Lumpur 50603 Malaysia

We demonstrate a q-switched erbium-doped fiber laser （EDFL） using a newly developed zinc oxide- （ZnO） based saturable absorber （SA）. The SA is fabricated by embedding a prepared ZnO powder into a poly（vinyl alcohol） film. A small piece of the film is then sandwiched between two fiber ferrules and is incorporated in an EDFL cavity for generating a stable q-switching pulse train. The EDFL operates at 1560.4nm with a pump power threshold of 11.8mW, a pulse repetition rate tunable from 22.79 to 61.43kHz, and the smallest pulse width of 7.00 μs. The q-switching pulse shows no spectral modulation with a peak-to-pedestal ratio of 62 dB indicating the high stability of the laser. These results show that the ZnO powder has a great potential to be used for pulsed laser applications.

关键词： Zinc Oxide-Based q-Switched Erbium-Doped Fiber Laser SA ZnO

Topological phase transitions and Majorana zero modes induced by the periodic potential in an antiferromagnetic chain

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Communications in Theoretical Physics 2023年第8期75卷 156-162页

作者： K W Shen q Chen College of Physics and Mechanical&Electrical Engineering Jishou UniversityJishou 416000China School of Computational Science and Electronics Hunan Institute of EngineeringXiangtan 411104China

We investigate the topological properties of an antiferromagnetic(AFM)chain with an on-site periodic potential,considering the intrinsic spin–orbit coupling and an external Zeeman field along with the *** results indicate that Majorana zero modes(MZMs)can be observed by adjusting the strength of the periodic *** have calculated the energy spectrum,the wave-function and transport properties,and all these results support the existence of MZMs in the AFM ***,multiple topological phase transitions occur as the strength of the periodic potential changes,and several regions support MZMs.

关键词： AFM chain Majorana zero modes topological phase transitions periodic potential