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Supersymmetric structures of Dirac oscillators in commutative and noncommutative spaces

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Chinese Physics B 2021年第11期30卷 228-232页

作者： jing-ying Wei Qing Wang Jian jing Department of Physics and Electronic Beijing University of Chemical TechnologyBeijing 100029China College of Physics and Technology Xinjiang UniversityUrumqi 830046China

The supersymmetric properties of a charged planar Dirac oscillator coupling to a uniform perpendicular magnetic field are *** find that there is an N=2 supersymmetric structure in both commutative and noncommutative *** construct the generators of the supersymmetric algebras explicitly and show that the generators of the supersymmetric algebras can be mapped onto ones which only contain the left or right-handed chiral phonons by unitary transformations.

关键词： Dirac oscillator anti-Jaynes-Cummings model Jaynes-Cummings model supersymmetry

A HOMOGENOUS-EQUILIBRIUM-MODEL BASED NUMERICAL CODE FOR CAVITATION FLOWS AND EVALUATION BY COMPUTATION CASES

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Journal of Hydrodynamics 2008年第2期20卷 186-194页

作者： CHEN ying LU Chuan-jing Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

A computer code, ELANEX, including several Homogenous-Equilibrium-Model （HEM） type cavitation models, were developed, to numerically simulate natural cavitation phenomena. The effectiveness of the code was checked by cavitation flows around the disk and cylinder body for a wide range of different cavitation numbers. Cavity profiles were compared with the analytic solution of disk and empirical formulae fitted from the experiment data, and contrast between different cavitation models were fulfilled as well. The cavity length and maximal cavity diameter were found to agree well with the analytic solutions, and detailed cavity profiles were in accordance with the experimental formula. Comparison with the hemisphere headed cylinder body presented a good agreement of the pressure coefficient with the experiment data. Reasonable drag-force coefficient variation and drag-force reduction effect were obtained.

关键词： cavitation numerical code disk hemisphere cavity profile pressure coefficient

Nonlinear Performance of MEMS Vibratory Ring Gyroscope

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Acta Mechanica Solida Sinica 2021年第1期34卷 65-78页

作者： Feng Liang Dong-Dong Liang ying-jing Qia College of Mechanical Engineering Yangzhou UniversityYangzhou225127China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Engineering College of Mechanical Engineering and Applied ElectronicsBeijing University of TechnologyBeijing100124China

Micro-electro-mechanical system(MEMS)gyroscopes are an important sort of inertial sensor for identifying parameters of spinning structures,such as the spinning speed and angular deviation,based on the Coriolis *** this paper,the nonlinear mechanism of MEMS vibratory ring gyroscopes is analyzed by applying a fully coupled nonlinear model,in which the gyroscopic coupling and geometrically and structurally nonlinear couplings are all taken into *** coupled differential equations governing the drive and sense motions are established via the Lagrangian *** simulation is conducted,and the key nonlinear components and energy transfer behaviors between the drive and sense modes are *** is revealed that the cubic rigidity nonlinearity is another significant factor leading to the coupling between the drive and sense modes other than the gyroscopic *** analysis is also carried out by using the method of multiple *** nonlinear frequency-amplitude responses of the drive and sense vibrations are obtained,and comprehensive parametric studies are *** significant effects of system damping,excitation amplitude,drive amplitude and spinning speed on the responses are discussed,which will facilitate to improve the nonlinear performance and sensitivity of the gyroscope.

关键词： MEMS vibratory ring gyroscope Nonlinear performance Drive mode Sense mode Method of multiple scales

Electrochemical study of sulfadiazine on a novel phthalocyanine-containing chemically modified electrode

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Chinese Chemical Letters 2013年第4期24卷 329-331页

作者： Xiao-Ping Hong jing-ying Ma Department of Chemistry Zhejiang Sci-Tech University Department of Construction.Zhejiang College of Construction

In this paper, cobalt tetraaminophthalocyanine （CoPc） was successfully deposited onto a carbon nanotubes modified electrode by consecutive cyclic scanning in supporting electrolyte containing CoPc to form phthalocyanine-containing chemically modified electrode. The electrochemistry of sulfadiazine was studied by voltammetric method and flow injection analysis at the new modified electrode. Compared with glassy carbon electrode, the new modified electrode exhibited exciting performance including low oxidation potential, high current response and promising flow injection response.

关键词： SulfadiazineCarbon nanotubePhthalocyanineElectrochemical detectionFlow injection analysis

Simulation,experimental evaluation and performance improvement of a cone dielectric elastomer actuator

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1296-1304页

作者： Hua-ming WANG jing-ying ZHU Ke-bei YE Jiangsu Key Laboratory of Precision and Micro-manufacturing Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Dielectric elastomer actuators (DEAs) are an emerging class of polymer actuation devices and have extensive application prospect in the field of robotics because of their light weight, high efficiency and large deformation. A cone DEA is manufactured and its working principle is analyzed. To obtain the deformation of elastomer and movement of DEA in advance, a finite element method (FEM) simulation is performed first. According to the working principle, two working equilibrium points of DEA, corresponding to the displacements of DEA with voltage off and on, are obtained and validated by experiments, thus work output in a workcycle is computed. Experiments show that the actuator can respond quickly when voltage is applied and can return to its original position rapidly when voltage is released. Simulation results agree well with experimental ones and the feasibility of DEA simulation is proved, and causes for the small difference between them in displacement output are analyzed. The performance of the actuator is improved from the aspects of both displacement and force output. A diamond four-bar linkage mechanism is used as the preload part and a displacement output of 17 mm is obtained. The force output of one actuating unit is about 1.77 N, so three actuating units are assembled in parallel and the force output is heightened to as high as 5.07 N.

关键词： Dielectric elastomer (DE) Actuator Simulation Performance improvement

MODELLING AND COMPUTATION OF UNSTEADY TURBULENT CAVITATION FLOWS

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Journal of Hydrodynamics 2006年第5期18卷 559-566页

作者： CHEN ying LU Chuan-jing WU Lei Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

Unsteady turbulent cavitation flows in a Venturi-type section and around a NACA0012 hydrofoil were simulated by two-dimensional computations of viscous compressible turbulent flow model. The Venturi-type section flow proved numerical precision and reliability of the physical model and the code, and further the cavitation around NACA0012 foil was investigated. These flows were calculated with a code of SIMPLE-type finite volume scheme, associated with a barotropic vapor/liquid state law which strongly links density and pressure variation. To simulate turbulent flows, modified RNG k-ε model was used. Numerical results obtained in the Venturi-type flow simulated periodic shedding of sheet cavity and was compared with experiment data, and the results of the NACA0012 foil show quasi-periodic vortex cavitation phenomenon. Results obtained concerning cavity shape and unsteady behavior, void ratio, and velocity field were found in good agreement with experiment ones.

关键词： turbulent cavitation Venturi NACA0012

Synthesis and Crystal Structure of an Organic-inorganic Complex [Hg(DMSO)_2(H_2O)]_2 [GeW_(12)O_(40)]·DMSO·H_2O

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Chinese Chemical Letters 2006年第8期17卷 1081-1084页

作者： jing Ping WANG Xiao Di DU Xian ying DUAN jing Yang NIU Institute of Molecular and Crystal Engineering School of Chemistry and Chemical Engineering Henan University Kaifeng 475001

An organic-inorganic mercury coordination compound [Hg（DMSO）2（H2O）]2 [GeW12O40]· DMSO·H2O （DMSO =dimethyl sulfoxide） has been synthesized and characterized by IR, UV spectra, elemental analysis, TG-DTA and X-ray single-crystal diffraction. Structural analysis revealed that in the title compound, the mercury is three-coordinated to show the distorted trigonal cone geometry, and depending on the electrostatic interaction to connect the polyanion [α-GeW12O40]^4-. TG-DTA study manifests the decomposition temperature of the polyanion framework in the title compound is 513.5℃, which is much higher than that of the anion framework. It means that the formation of the organic-inorganic mercury coordination compound made the polyanion [α-GeW12O40]^4- to he more stable.

关键词： Polyoxometalates organic-inorganic complex crystal structure.

Comprehensive evaluation of machine learning algorithms applied to TBM performance prediction

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Underground Space 2022年第1期7卷 37-49页

作者： Jie Yang Saffet Yagiz ying-jing Liu Farid Laouafa Zhongtian Construction Group Co.Ltd HangzhouChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina School of Mining and Geosciences Nazarbayev UniversityNur-Sultan 010000Kazakhstan National Institute for Industrial Environment and Risks(INERIS) Verneuil-en-HalatteFrance

To date,the accurate prediction of tunnel boring machine(TBM)performance remains a considerable challenge owing to the complex interactions between the TBM and *** evolutionary polynomial regression(EPR)and random forest(RF),this study devel-ops two novel prediction models for TBM *** models can predict the TBM penetration rate and field penetration index as outputs with four input parameters:the uniaxial compressive strength,intact rock brittleness index,distance between planes of weakness,and angle between the tunnel axis and planes of weakness(a).First,the performances of both EPR-and RF-based models are examined by comparison with the conventional numerical regression method(i.e.,multivariate linear regression).Subsequently,the performances of the RF-and EPR-based models are further investigated and compared,including the model robustness for unknown datasets,interior relationships between input and output parameters,and variable *** results indicate that the RF-based model has greater prediction accuracy,particularly in identifying outliers,whereas the EPR-based model is more convenient to use by field engineers owing to its explicit *** EPR-and RF-based models can accurately identify the relationships between the input and output *** ensures their excellent generalization ability and high prediction accuracy on unknown datasets.

关键词： Tunnel boring machine Evolutionary polynomial regression Random forest Optimization Regularization

Case Report:A case study of imported pulmonary coccidioidomycosis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第4期12卷 298-302页

作者： Zheng-yang WANG Sheng-lan WEN Ke-jing ying Department of Respiratory Medicine Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou 310016 China

Coccidioidomycosis is an endemic disease of the Western *** cases in non-endemic areas are mostly *** a history of exposure is critical for performing the diagnosis of coccidioidomycosis,especially for cases occurring in a non-endemic *** this study,a 71-year-old Chinese male presented to our hospital with chronic cough and malaise,and was found to have a mass in the middle lobe of right *** had been visiting Arizona,USA for four months before *** coccidioidomycosis was confirmed by the results of histopathological examination after *** microscopic features of Coccidioides are definitely diagnostic,but need be differentiated from other budding yeast infection or carcinoma histopathologically.

关键词： Coccidioidomycosis Imported disease Pulmonary fungal infection Endemic disease