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Effective properties of coated fibrous piezoelectric composites with spring-type interfaces under anti-plane mechanical and in-plane electrical loads

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Science China(Physics,Mechanics & Astronomy) 2016年第10期59卷 58-65页

作者： yin shi YongPing Wan Zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University

In this paper,we investigate the effective properties of three-phase(matrix/coating/fiber)cylindrical piezoelectric composites with imperfect interfaces under anti-plane mechanical and in-plane electrical *** using the electromechanically coupling spring-type interface model and the generalized self-consistent method(GSM),we analytically derived the effective electroelastic *** present solutions include as special cases the three-phase cylindrical piezoelectric composites with perfect interfaces as well as the two-phase(matrix/fiber)case with imperfect or perfect *** calculations are graphically shown to demonstrate dependence of the effective moduli on the interfacial *** particular size-dependent characteristic due to the interfacial imperfection is also discussed.

关键词： effective moduli piezoelectric composites spring-type interface generalized self-consistent method size effect

Multi-disciplinary design optimization with variable complexity modeling for a stratosphere airship

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Chinese Journal of Aeronautics 2019年第5期32卷 1244-1255页

作者： shi yin Ming ZHU Haoquan LIANG School of Aeronautic Science and Engineering Beihang University School of Automation Science and Electrical Engineering Beihang University

This paper proposes a hybrid architecture based on Multi-disciplinary Design Optimization(MDO) with the Variable Complexity Modeling(VCM) method, to solve the problem of general design optimization for a stratosphere airship. Firstly, MDO based on the Concurrent SubSpace Optimization(CSSO) strategy is improved for handling the subsystem coupling problem in stratosphere airship design which contains aerodynamics, structure, and energy. Secondly, the VCM method based on the surrogate model is presented for reducing the computational complexity in high-fidelity modeling without loss of accuracy. Moreover, the global-to-local optimization strategy is added to the architecture to enhance the process. Finally, the result gives a prominent stratosphere airship general solution that validates the feasibility and efficiency of the optimization architecture. Besides, a sensitivity analysis is conducted to outline the critical impact upon stratosphere airship design.

关键词： Multi-disciplinary design optimization Sensitivity analysis Stratosphere airship Surrogate model Variable complexity modeling

SIMULATED MATHEMATICAL MODEL FOR HIGH PRESSURE CYLINDER WALL TEMPERATURE OF HOMEMADE TURBINE

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 442-445页

作者： shi Xiaoping Zhu yin Control and Simulation Center Harbin Institute of Technology Harbin 150001 China

In order to balance the contradiction between the demand of high precision and that of short time interval of model computing for the power plant simulator, a set of simulated mathematical models are constructed. The model describes the cylinder wall temperature located at four key positions of the high pressure cylinder. The simulated model is confirmed to be not only simple but also precise via comparison between the simulated results and the autoptic data of a power plant.

关键词： Turbine Cylinder wall temperature Mathematical model Simulation

Microstructures of Fe_(77-x)Ni_(x)Cu_(1)Nb_(2)P_(14)B_(6) Soft Magnetic AlloysStudied by X-Ray Absorption Fine Structure

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Chinese Physics Letters 2000年第9期17卷 683-685页

作者： yin shi-Long BIAN Qing WEI shi-qiang Department of Mathematics and Physics Hohai UniversityNanjing 210024 Department of Basic Science Institute of Communication EngineeringNanjing 210016 National Synchrotron Radiation Laboratory and Center for Fundamental Physics University of Science and Technology of ChinaHefei 230029

Local structures of the mechanically alloyed Fe_(77-x)Ni_(x)Cu_(1)Nb_(2)P_(14)B_(6)soft magnetic materials have been in vestigated by x-ray absorption fine *** results show that mechanical alloying(MA)can drive theFe_(77-x)Ni_(x)Cu_(1)Nb_(2)P_(14)B_(6)powder mixture to produce amorphous alloy when the atomic concentration of Fe ele ment is about and over 40%.On the contrary,the MA Fe_(77-x)Ni_(x)Cu_(1)Nb_(2)P_(14)B_(6)is a solid solution with an fcc-like structure in the region of lower Fe atomic concentration(<22%),preserving a medium-range order around Ni and Fe ***,we have found that the local structure geometry of Fe atom is similar to that of Ni atom for all the MA Fer7-xNixCu1 Nb2P14B6 *** indicates that the local structures of Fe and Ni atoms in a Fe_(77-x)Ni_(x)Cu_(1)Nb_(2)P_(14)B_(6)sample only depend on the x value of element Ni after ball milling.

关键词： structure alloying alloy

Privileged chiral catalysts in asymmetric Morita-Baylis-Hillman/aza-Morita-Baylis-Hillman reaction

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Chinese Science Bulletin 2010年第17期55卷 1699-1711页

作者： WEI yin shi Min State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

In the past decade, the asymmetric Morita-Baylis-Hillman (MBH)/aza-Morita-Baylis-Hillman (aza-MBH) reaction has attracted great attention because it leads to the formation of densely functionalized products in a catalytic and atom-economic way. The MBH/aza-MBH adducts can be further applied in a wide variety of organic synthesis, such as peptide synthesis and heterocyclic compounds synthesis. After a lot of attempts to improve the enantioselectivity, many types of chiral organocatalysts have been identified as highly enantioselective organocatalysts in MBH/aza-MBH reaction. Especially, certain "privileged chiral catalysts" are highly enantioselective in MBH/aza-MBH reaction, which are designed and developed through introducing bi-/multi-functional groups on the so-called "privileged structures" such as cinchona alkaloids, BINAP/BINOL. This review summarizes the exciting advances about the design and development of chiral catalysts derived from "privileged structures" and their applications in asymmetric MBH/aza-MBH reaction.

关键词：手性催化剂选择性反应不对称氮杂特权对映选择性有机催化剂有机合成

Dendritic Boundary Corrosion of AA2198 Weld Using Fiber Laser Welding with Al–Cu Filler Wire

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Acta Metallurgica Sinica(English Letters) 2018年第7期31卷 735-741页

作者： Jun-Xia Lu Ling Chang shi-Kai Wu shi-Kun yin Institute of Laser Engineering Beijing University of Technology

The microstructures and corrosion behaviors of AA2198-T851 alloy and weld were analyzed under corrosive conditions. Weld was formed using an innovative fiber laser welding process with AA2319 Al-Cu filler wire. The metallurgic morphology and distribution of the chemical compositions were determined using imaging techniques such as optical micrograph, scanning electron micrograph, high-resolution transmission electron microscopy, energy-dispersive X-ray spectrometry and X-ray diffraction. Corrosion was evaluated using an immersion test and electrochemical impedance spectroscopy in 3.5% NaC1 solution at room temperature. Results indicate that the parent alloy suffered from pitting corrosion during the initial 4-h immersion which was caused by the inhomogeneous distribution of its chemical compo- nents and the different intermetallics formed during the rolling process. The weld experienced dendritic boundary corrosion under the same conditions due to the addition of the Al-Cu filler and rapid solidification during laser welding, which led to the precipitates Cu enrichment along the grain boundary. When a welding joint was immersed in the solution for 5 days, a big crack was observed across the center of the weld. In comparison, there was good corrosion resistance in the heat- affected zone with a compact protective film.

关键词： 2198 Aluminum alloy. Fiber laser welding Dendritic boundary corrosion Al-Cu filler wire

Effects of Austenizing Temperature on Reprecipitation of BN

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Journal of Iron and Steel Research International 2013年第9期20卷 99-104页

作者： yin shi-ke A Rong Mitsuru Tanino China Iron and Steel Research Institute Group Fundamental Research Laboratory Nippon Steel Co.

Most of BN was precipitated around the spherical MnS and formed the compound of MnS and BN during the isothermal treatment at 850 ℃ after austenizing at 950-1050 ℃. Most of MnS was transformed into polygon when austenized at 1 150 ℃ or above, which could not be the nuclei of BN anymore. During the insulation process at 850 ℃, MnS kept the state of monomer. The compound of MnS and BN at earlier time was of fine polycrystalline in spherality and BN was formed as a plate-like monocrystal on a certain part of the polycrystalline when its dimension reached 0.6 μm.

关键词： austenizing temperature BN repreeipitation isothermal treatment

A Multi-Condition Relighting with Optimal Feature Selection to Robust Face Recognition with Illumination Variation

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China Communications 2014年第6期11卷 99-107页

作者： HAO Yujie LIN Jie yin shi School of Computer Science and Engineering University of Electronic Science and Technology of China Department of Computer Science University of Illinois at Chicago

In this paper, we proposed a new approach for face recognition with robust to illumination variation. The improved performance to various lights in recognition is obtained by a novel combination of multicondition relighting and optimal feature selection. Multi-condition relighting provides a "coarse" compensation for the variable illumination, and then the optimal feature selection further refines the compensation, and additionally offers the robustness to shadow and highlight, by deemphasizing the local mismatches caused by imprecise lighting compensation, shadow or highlight on recognition. For evaluation, two databases with various illumination mismatches have been used. The results have demonstrated the improved robustness of the new methods.

关键词： relighting illumination variation robustness face recognition.

Advances in laser-plasma interactions using intense vortex laser beams

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 14-42页

作者： yin shi Xiaomei Zhang Alexey Arefiev Baifei Shen Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026China Department of Physics Shanghai Normal UniversityShanghai 200234China Department of Mechanical and Aerospace Engineering University of California at San DiegoLa JollaCA 92093USA

Low-intensity light beams carrying orbital angular momentum(OAM),commonly known as vortex beams,have garnered significant attention due to promising applications in areas ranging from optical trapping to *** recent years,there has been a surge in global research exploring the potential of high-intensity vortex laser beams and specifically their interactions with *** paper provides a comprehensive review of recent advances in this *** with conventional laser beams,intense vortex beams exhibit unique properties such as twisted phase fronts,OAM delivery,hollow intensity distribution,and spatially isolated longitudinal *** distinct characteristics give rise to a multitude of rich phenomena,profoundly influencing laser-plasma interactions and offering diverse *** paper also discusses future prospects and identifies promising general research areas involving vortex *** areas include low-divergence particle acceleration,instability suppression,high-energy photon delivery with OAM,and the generation of strong magnetic *** growing scientific interest and application potential,the study of intense vortex lasers is poised for rapid development in the coming years.

关键词： intense vortex laser orbital angular momentum laser plasma interactions high power laser high energy density science