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Anomalous Transport Characteristics of High Temperature Superconductors and Josephson Currents

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Communications in Theoretical Physics 2002年第3期38卷 379-384页

作者： LIANG Fang-ying LI zuo-Hong Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China Institution of Science and Technology for OPTO-Electronic Information Yantai University Yantai 26400 Shangdong Province China

The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach *** evaluated the vortex equation and found that the signs of the high temperature superconductor current and theJosephson current can reverse. Some explicit expressions for different cases are derived, which accord with experimentaldata.

关键词： superconductivity, junction, Josephson current

Visible Light Photocatalytic Properties and Thermochromic Phenomena of Nanostructured BiOCl Microspheres

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Journal of Materials Science & Technology 2014年第11期30卷 1130-1133页

作者： Jiushan Cheng Cong Wang Yinfang Cui ying Sun ying zuo Center for Condensed Matter and Material Physics Department of PhysicsBeihang University

Black nanostructured BiOCI microspheres were directly synthesized by a hydrothermal method. The black ball- like BiOCI microspheres and black flower-like BiOCI microspheres were obtained using different surfactant. The color of the BiOCI microspheres turned from black to white when being annealed at 400 ℃ in air for 3 h and could be recovered to black by exposure to ultraviolet light for a few hours. The photocatalytic activity of both the black and the white BiOCI microspheres was characterized by the photo-degradation of methyl orange dye under visible light irradiation. The black ball-like nanostructure BiOCI displayed the best photocatalytic activity, compared with the white BiOCI and the black flower-like BiOCI. It can degrade the methyl orange dye to 20% within 70 min under visible light irradiation. The high activity of the BiOCI ball-like sphere may own to its special morphology, strong absorption in visible light range and the existence of oxygen vacancies.

关键词： Photocatalysis Black BiOCI Microsphere Thermochromic

Radial Additive Friction Stir Repairing of Mechanical Hole Out of Dimension Tolerance of AZ31 Magnesium Alloy Assisted by Stationary Shoulder:Process and Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2021年第10期34卷 1345-1360页

作者： ying-ying zuo Hua Liu Peng Gong Shu-De Ji Bao-Sheng Wu College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China

Radial additive friction stir repairing(R-AFSR)assisted by stationary shoulder was put forward in the present study,which can be employed to repair the mechanical hole out of dimension tolerance of AZ31 magnesium alloy *** results show that the stationary shoulder has sealed-barrier,heat-sink and extra-forging *** heat-sink effect improves the microstructure uniformity along the stir zone(SZ)thickness and the surface appearance of repaired hole,and the sealedbarrier and extra-forging effects eliminate the super-fine grain band in the ***,these three effects improve the formation quality of repaired region,thereby enhancing the mechanical properties of repaired mechanical hole compared with conventional *** tensile and compressive shear strengths of the repaired hole by stationary shoulder R-AFSR both increase first and then decrease when the rotating speed changes from 1200 to 1800 rpm,and these maximum values,respectively,reach 190±3 MPa and 64.5±2 MPa at 1400 *** addition of stationary shoulder during R-AFSR can obtain a higher-quality repaired hole and broaden the repairing process window.

关键词： Stationary shoulder Radial additive friction stir repairing Mechanical hole out of dimension tolerance AZ31 magnesium alloy Microstructure Mechanical properties

Digital twin-enabled adaptive scheduling strategy based on deep reinforcement learning

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Science China(Technological Sciences) 2023年第7期66卷 1937-1951页

作者： GAN XueMei zuo ying ZHANG AnSi LI ShaoBo TAO Fei School of Mechanical Engineering Guizhou UniversityGuiyang 550025China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China

The modern complicated manufacturing industry and smart manufacturing tendency have imposed new requirements on the scheduling method,such as self-regulation and self-learning *** traditional scheduling methods cannot meet these needs due to their ***-learning is an inherent ability of reinforcement learning(RL) algorithm inhered from its continuous learning and trial-and-error ***-regulation of scheduling could be enabled by the emerging digital twin(DT) technology because of its virtual-real mapping and mutual control *** paper proposed a DT-enabled adaptive scheduling based on the improved proximal policy optimization RL algorithm,which was called explicit exploration and asynchronous update proximal policy optimization algorithm(E2APPO).Firstly,the DT-enabled scheduling system framework was designed to enhance the interaction between the virtual and the physical job shops,strengthening the self-regulation of the scheduling ***,an innovative action selection strategy and an asynchronous update mechanism were proposed to improve the optimization algorithm to strengthen the self-learning ability of the scheduling ***,the proposed scheduling model was extensively tested in comparison with heuristic and meta-heuristic algorithms,such as wellknown scheduling rules and genetic algorithms,as well as other existing scheduling methods based on reinforcement *** comparisons have proved both the effectiveness and advancement of the proposed DT-enabled adaptive scheduling strategy.

关键词： agent reinforcement learning digital twin adaptive scheduling generalization

Non-keyhole Friction Stir Welding for 6061-T6 Aluminum Alloy

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 763-772页

作者： Peng Gong ying-ying zuo Shu-De Ji De-Jun Yan Deng-Chang Li Zhen Shang College of Aerospace Engineering Shenyang Aerospace UniversityShenyang110136China Guangdong Key Laboratory of Enterprise Advanced Welding Technology for Ships CSSC Huangpu Wenchong Shipbuilding Company LimitedGuangzhou510715China

A novel non-keyhole friction stir welding technique was proposed to weld the butt joint of 6061-T6 aluminum alloy with the thickness of 6 mm.A sound joint was obtained by this technique,simultaneously eliminating the flash,shoulder mark and keyhole *** sleeve directly affected zone(SDAZ)and the sleeve indirectly affected zone(SIAZ)were divided into the joint according to the plunging position of the hollow *** lack of root penetration defect was avoided when the plunging depth of the hollow sleeve was only 4.2 mm,because the hollow part inside the sleeve improved the material flow below the *** S-shaped line was left at the SIAZ,and the height of it had the minimum value of 1.47 mm at 20 mm/*** the failure location of the joint was in SIAZ/SDAZ or the heat-affected zone(HAZ)depended on the height and bonding strength of the S-shaped *** joint fracture location changed from the SIAZ/SDAZ at 35 mm/min to the HAZ at 20 and 30 mm/*** maximum tensile strength of 224.3 MPa was obtained at 30 mm/min which was 73.7%of that of the base *** fracture surface morphology exhibited the typical ductile fracture.

关键词： Non-keyhole friction stir welding Welding tool simplification Microstructures Material flow Mechanical properties

A highly selective and sensitive fluorescent chemosensor for Zn^(2+)

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Chinese Chemical Letters 2008年第10期19卷 1240-1243页

作者： Xiu ying Zhang zuo Hui Wang Lin Yang School of Chemistry and Environmental Science Key Ltlboratory for Environmental Pallution Control Technology of Henan Province Henan Normal University Xinxiang 453007 China

A new selective Zn^2＋ fluorescent chemosensor, o-vanillin-4-ethoxybenzoylhydrazone （1）, was designed and prepared. Free 1 mainly displayed very weak fluorescence at 480 nm upon excitation at 403 nm. It displayed high selectivity for Zn^2＋ and had a 518- fold fluorescent enhancement upon binding of Zn^2＋, while the other cation ions had only little influence on the fluorescence of 1. Mechanism of enhancement of l＇s fluorescence by Zn^2＋ was briefly discussed.

关键词： Chemosensor Zinc ion Fluorescence enhancement N-Acylhydrazone

INFLUENCE OF ALCOHOL-BASED NONSOLVENTS ON THE FORMATION AND MORPHOLOGY OF PVDF MEMBRANES IN PHASE INVERSION PROCESS

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Chinese Journal of Polymer Science 2006年第3期24卷 281-289页

作者： Dan-ying zuo Bao-ku Zhu Jian-hua Cao 徐又一 Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China

Through the preparation of PVDF membranes using various nonsolvent coagulation baths following the phase inversion process, the influence of alcohol-based nonsolvents on the formation and structure of PVDF membranes were investigated. The light scattering and light transmission measurements were used to characterize the equilibrium phase diagram and the gelation speed, respectively. The locations of the crystallization-induced gelation boundaries for various systems and precipitation processes were explained from the corresponding thermodynamic and kinetic parameters. It was found that the better affinity between alcohol-based nonsolvents and DMAc solvent caused the gelation boundaries further away from the PVDF-DMAc axis with the coagulation bath varying from water, methanol, ethanol to iso-propanol. Due to the lower exchange rate of DMAc and alcohols, the delayed demixing took place for the membrane-forming using alcohols as baths, and the delayed time became longer when the coagulation bath was changed from methanol, ethanol to iso-propanol. The characterization results of membranes indicate that the influence of nonsolvents on the phase diagram and the precipitation process are in agreement with those on the membrane morphology. The better thermodynamic stability and a low exchange diffusion rate of PVDF/DMAc/alcohols favor the liquid-solid phase separation in gelation process, and therefore yield the membranes with a porous upper surface, a particular bottom surface and symmetrical structure.

关键词： Poly(vinylidene fluoride) membrane Kinetic diffusion Thermodynamic phase diagram Immersion precipitation Alcohol-based coagulation bath.

Audio-visual voice activity detection

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Frontiers of Electrical and Electronic Engineering in China 2006年第4期1卷 425-430页

作者： LIU Peng WANG zuo-ying Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

In speech signal processing systems,frame-energy based voice activity detection(VAD)method may be interfered with the background noise and non-stationary characteristic of the frame-energy in voice *** purpose of this paper is to improve the performance and robustness of VAD by introducing visual ***,data-driven linear transformation is adopted in visual feature extraction,and a general statistical VAD model is *** the general model and a two-stage fusion strategy presented in this paper,a concrete multimodal VAD system is *** show that a 55.0%relative reduction in frame error rate and a 98.5%relative reduction in sentence-breaking error rate are obtained when using multimodal VAD,compared to frame-energy based audio *** results show that using multimodal method,sentence-breaking errors are almost avoided,and frame-detection performance is clearly improved,which proves the effectiveness of the visual modal in VAD.

关键词： speech recognition voice activity detection multimodal

Digital twin-driven green material optimal selection and evolution in product iterative design

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Advances in Manufacturing 2023年第4期11卷 647-662页

作者： Feng Xiang Ya-Dong Zhou Zhi Zhang Xiao-Fu Zou Fei Tao ying zuo Key Laboratory of Metallurgical Equipment and Control Technology Ministry of EducationWuhan University of Science and TechnologyWuhan430081People’s Republic of China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan430081People’s Republic of China Institute of Artificial Intelligence Beihang UniversityBeijing100191People’s Republic of China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191People’s Republic of China Research Institute for Frontier Science Beihang UniversityBeijing100191People’s Republic of China

In recent years,green concepts have been integrated into the product iterative design in the manufacturing field to address global competition and sustainability ***,previous efforts for green material optimal selection disregarded the interaction and fusion among physical entities,virtual models,and users,resulting in distortions and inaccuracies among user,physical entity,and virtual model such as inconsistency among the expected value,predicted simulation value,and actual performance value of evaluation ***,this study proposes a digital twin-driven green material optimal selection and evolution method for product iterative ***,a novel framework is ***,an analysis is carried out from six perspectives:the digital twin model construction for green material optimal selection,evolution mechanism of the digital twin model,multi-objective prediction and optimization,algorithm design,decision-making,and product function ***,taking the material selection of a shared bicycle frame as an example,the proposed method was verified by the prediction and iterative optimization of the carbon emission index.

关键词： Product iterative design Digital twin(DT) Green material optimal selection Evolution mechanism Iterative optimization