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Chinese Journal of Mechanical Engineering 2024年第2期37卷 163-183页

作者： Chenbing Ni Junjie Zhu Youqiang Wang dejian Liu Xuezhao Wang Lida Zhu School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266525China School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China

Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing *** prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured *** this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAM).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dimensions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAM is ***,the effect of phase difference on the elliptical shape in 2D/3D ultrasonic elliptical vibration-assisted milling(UEVAM)was *** to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAM,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro *** prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1D rotary UVAM,2D and 3D UEVAM due to the unfavorable effect of axial ultrasonic vibration on the surface *** study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAM.

关键词： Theoretical modeling Microtextured surface Ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness

Presenting degenerate Ringel-Hall algebras of type B

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science China mathematics 2012年第5期55卷 949-960页

作者： FAN LiJuan1 & ZHAO ZhongHua2,1department of mathematics,Beijing Normal University,Beijing 100875,China 2department of mathematics and computer science,School of science,Beijing University of Chemical Technology,Beijing 100029,China 1. department of mathematics Beijing Normal University Beijing 100875 China2. Department of Mathematics and Computer Science School of Science Beijing University of Chemical Technology Beijing 100029 China

We give a presentation for the degenerate Ringel-Hall algebras of type B by studying the corresponding generic extension monoid *** an application,it is shown that the degenerate Ringel-Hall algebras of type B admit m... 详细信息

关键词： degenerate Ringel-Hall algebras generic extension monoid algebras Auslander-Reiten quivers Frobenius morphism

Research on denoising of joint detection signal of water quality with multi-parameter based on IEEMD

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Optoelectronics Letters 2024年第2期20卷 107-115页

作者： LI Wen LI dejian MA Yongyue TIAN Wang WEN Xin LI Jie Institute of Mechanical and Electrical Engineering North China University of TechnologyBeijing 100144China1

An improved ensemble empirical mode decomposition(IEEMD) is suggested to process water quality spectral signals in order to address the issue that noise interference makes it difficult to extract and evaluate water quality spectral *** algorithm effectively solves the problems of modal mixing,poor reconstruction accuracy in the empirical mode decomposition(EMD),and a large amount of calculation in the ensemble empirical mode decomposition(EEMD).Based on EEMD,IEEMD firstly preprocesses the original water quality spectral signals,then performs Savitzky-Golay(S-G) smoothing on the decomposed effective intrinsic mode function(IMF) components,and finally reconstructs them to obtain the denoised *** sample data at different concentrations can be accurately analyzed based on the noise-reduced spectral *** this paper,three water quality parameters are used as research objects:benzene(C_(6)H_(6)),benzo(b)fluoranthene(C_(20)H_(12)),and chemical oxygen demand(COD).The original water quality multi-parameter(C_(6)H_(6),C_(20)H_(12),COD) spectral signals were subjected to denoising based on the IEEMD and the water quality multi-parameter joint detection *** signal-to-noise ratio(SNR) and the correlation coefficient(R^(2)) of the fitted curves obtained from the processing of the IEEMD were compared and analyzed with those obtained from the processing of the EMD and the *** experimental results show that the SNR of the spectral signals and the R^(2) of the fitting curve in three water quality parameters have been significantly ***,the IEEMD effectively improves the phenomenon of modal mixing,reduces the amount of calculation,improves the reconstruction accuracy,and provides an important guarantee for the effective extraction of multi-parameter spectral signals of water quality.

关键词： signal parameter noise

Advancing microarray fabrication:One-pot synthesis and highresolution patterning of UV-crosslinkable perovskite quantum dots

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Nano Research 2024年第9期17卷 8600-8609页

作者： Linfeng Yuan dejian Chen Kun He Jiamin Xu Kunyuan Xu Jie Hu Sisi Liang Haomiao Zhu CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of sciences Beijing 100049China College of Chemistry and Materials science Fujian Normal UniversityFuzhou 350007China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021China

The development of highly efficient,solution-processable,and environmentally stable perovskite quantum dots(PQDs)is crucial for their accurate high-resolution patterning and subsequently enabling the practical deployment of PQD based emissive display *** study presents an innovative strategy for integrating all-inorganic PQDs and ultraviolet(UV)crosslinkable acrylate polymer at a structural and functional *** achievement is accomplished by meticulous design and one-pot synthesis of UV-crosslinkable CsPbX_(3)(X=Cl,Br,I)PQDs solution,which exhibit outstanding environmental *** the solution-processable characteristics of the resulting UV-crosslinkable PQDs,precise patterning of high-resolution(2μm,7608 pixels·in.^(-1))and colorful PQDs microarrays can be readily achieved through inkjet printing and high-throughput photolithography(~2μm in pitch line/space patterning).The UV cross-linked process guarantees a homogeneous distribution of PQDs,effectively mitigating coffee ring effect and improving the overall quality of stereoscopic *** photo-cured PQDs film,which undergoes free radical photopolymerization,displays an impressive photoluminescence quantum yield(PL QY)of up to 89.2%,reaching 98%of the value observed in the solution *** approach outlined in this research is both cost-effective and pragmatic,exhibiting tremendous promise for diverse system-level integrated optoelectronic devices,such as ultra-high-resolution micro-light-emitting device(micro-LED)displays.

关键词： perovskite quantum dots microarrays cross-linking strategy Inkjet printing photolithography

VLBI with SKA:Possible Arrays and Astrometric science

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Research in Astronomy and Astrophysics 2024年第7期24卷 1-33页

作者： Yingjie Li Ye Xu Jingjing Li Shuaibo Bian Zehao Lin Chaojie Hao dejian Liu Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China University of science and Technology of China Hefei 230026China

The next generation of very long baseline interferometry(VLBI)is stepping into the era of microarcsecond(μas)astronomy,and pushing astronomy,especially astrometry,to new *** with the Square Kilometre Array(SKA),SKA-VLBI,will increase current sensitivity by an order of magnitude,and reach astrometric precision routinely below 10μas,even challenging 1μ*** advancement allows precise parallax and proper motion measurements of various celestial *** improvements can be used to study objects(including isolated objects,and binary or multiple systems)in different stellar stages(such as star formation,main-sequence stars,asymptotic giant branch stars,pulsars,black holes,white dwarfs,etc.),unveil the structure and evolution of complex systems(such as the Milky Way),benchmark the international celestial reference frame,and reveal cosmic ***,the theory of general relativity can also be tested with SKA-VLBI using precise measurements of light deflection under the gravitational fields of different solar system objects and the perihelion precession of solar system objects.

关键词： astrometry-parallaxes-stars kinematics and dynamics-ISM kinematics and dynamics-Galaxy kinematics and dynamics-galaxies kinematics and dynamics-gravitation

Data classification from the inverse nth power gravitation

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science China(Information sciences) 2012年第1期55卷 184-190页

作者： XU HuaRong1,WANG XiaoDong1,ZENG ZhiQiang1&fang Qiu2 1department of computer science and Technology,Xiamen University of Technology,Xiamen 361024,China 2department of Mechanical Engineering,Xiamen University of Technology,Xiamen 361024,China 1. department of computer science and Technology Xiamen University of Technology Xiamen 361024 China2. Department of Mechanical Engineering Xiamen University of Technology Xiamen 361024 China

By the inverse nth power gravitation in physics,a novel classifier for data classification,called the I-n-PG classifier,is *** the I-n-PG model,training samples from each class are regarded as a system of particles and an I-n-PG field is defined for each class.A test sample belongs to the class whose particle system has the maximum I-n-PG to this test *** on large numbers of real data show that the I-n-PG classifier can provide a good classification *** with the nearest neighbor classifier and SVM,performances of the I-n-PG classifier are always superior/close to the better one of them,and thus the I-n-PG classifier has also a wide range of adaptability to data sets.

关键词： data classification inverse nth power gravitation

Dynamic memory paravirtualization transparent to guest OS

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science China(Information sciences) 2010年第1期53卷 77-88页

作者： WANG XiaoLin1, SUN YiFeng1, LUO YingWei1, WANG ZhenLin2, LI Yu1, ZHANG BinBin1, CHEN HaoGang1 & LI XiaoMing1 1department of computer science and Technology, Peking University, Beijing 100871, China 2department of computer science, Michigan Technological University, Houghton, MI 49931, USA 1. department of computer science and Technology Peking University Beijing 100871 China2. Department of Computer Science Michigan Technological University Houghton MI 49931 USA

This paper introduces dynamic paravirtualization, which imitates paravirtualization and aims at reducing VM exits of full virtualization with hardware support. In dynamic paravirtualization, VMM (virtual machine monitor) dynamically monitors and replaces the hot instructions, which cause most VM exits. It is transparent to the guest OS such that the legacy OSes can benefit from this optimization. Our study focuses on reducing the overhead of memory virtualization-dynamic memory paravirtualization (DMP). We implant a new memory management mechanism in VMM such that all user-mode page faults can be handled by the guest OS directly without VM exits. We implement a prototype of dynamic memory paravirtulization based on a version of KVM using Intel VT. Our experimental results show that our technique essentially eliminates the overhead of VM exits caused by page faults. Dynamic memory paravirtualization can achieve the effectiveness of paravirtualization without changing the source code of guest OS.

关键词： virtualization virtual machine monitor paravirtualization dynamic paravirtualization hot instructions VM exits code implantation

Limit theory of restricted range approximations of complex-valued continuous functions

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science China mathematics 2007年第10期50卷 1427-1440页

作者： Xian-fa LUO~1 Chong LI~(2+) ~1 School of mathematics and computer science,Jishou University,Jishou 416000,China ~2 department of mathematics,Zhejiang University,Hangzhou 310027,China 1. School of mathematics and computer science Jishou University Jishou 416000 China 2. department of mathematics Zhejiang University Hangzhou 310027 China

This paper is concerned with the problem of the best restricted range approximations of complex-valued continuous functions. Several properties for the approximating set PΩ such that the classical characterization results and/or the uniqueness results of the best approximations hold are introduced. Under the very mild conditions, we prove that these properties are equivalent that P is a Haar subspce.

关键词： restricted range approximation, Haar subspace, characterization, uniqueness

Robust H-infinity fuzzy control for uncertain Markovian jump nonlinear singular systems with wiener process

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控制理论与应用（英文版） 2010年第2期8卷 205-210页

作者： Aiqing ZHANG 1 , Huajing fang 2 (1.College of mathematics and computer science, Jianghan University, Wuhan Hubei 430056, China 2.department of Control science and Engineering, Huazhong University of science and Technology, Wuhan Hubei 430074, China) College of mathematics and computer science Jianghan University Wuhan Hubei China department of Control science and Engineering Huazhong University of Science and Technology Wuhan Hubei China

This paper deals with the problems of robust stochastic stabilization and H-infinity control for Markovian jump nonlinear singular systems with Wiener process via a fuzzy-control approach. The Takagi-Sugeno (T-S) fuzzy model is employed to represent a nonlinear singular system. The purpose of the robust stochastic stabilization problem is to design a state feedback fuzzy controller such that the closed-loop fuzzy system is robustly stochastically stable for all admissible uncertainties. In the robust H-infinity control problem, in addition to the stochastic stability requirement, a prescribed performance is required to be achieved. Linear matrix inequality (LMI) sufficient conditions are developed to solve these problems, respectively. The expressions of desired state feedback fuzzy controllers are given. Finally, a numerical simulation is given to illustrate the effectiveness of the proposed method.

关键词： Fuzzy control H-infinity control Singular systems Stochastic stability Linear matrix inequality (LMI)