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An Inequality for the Perron Pair of an Irreducible and Symmetric Nonnegative Tensor with Application

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Journal of the Operations Research Society of China 2017年第1期5卷 65-82页

作者： Mao-Lin Che yi-min Wei School of Mathematical Sciences Fudan UniversityShanghai 200433China School of Mathematical Sciences and Shanghai Key Laboratory of Contemporary Applied Mathematics Fudan UniversityShanghai 200433China

The main purpose of this paper is to consider the Perron pair of an irreducible and symmetric nonnegative tensor and the smallest eigenvalue of an irreducible and symmetric nonsingular *** analyze the analytical property of an algebraic simple eigenvalue of symmetric *** also derive an inequality about the Perron pair of nonnegative tensors based on plane stochastic *** finally consider the perturbation of the smallest eigenvalue of nonsingular M-tensors and design a strategy to compute its smallest *** verify our results via random numerical examples.

关键词： Nonnegative tensor Symmetric tensor Irreducible tensor M-Tensor H-Eigenpair An algebraic simple eigenvalue The Perron pair The smallest eigenvalue Perturbation

A fluid dynamics route for producing graphene and its analogues

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Chinese Science Bulletin 2014年第16期59卷 1794-1799页

作者： min yi Zhigang Shen Jinyang Zhu Beijing Key Laboratory for Powder Technology Research & Development Beijing University of Aeronautics and Astronautics ministry-of-Education Key Laboratory of Fluid Mechanics Beijing University of Aeronautics and Astronautics State Key Laboratory for Turbulence & Complex Systems Peking University

A novel fluid dynamics route for scalable and efficient production of graphene and its analogues is *** force microscopy and transmission electron microscopy analyses strongly suggest that the bulk layered materials(graphite,BN,MoS2,and WS2)are efficiently exfoliated into individual layers containing mono-and few-layer *** fluid dynamics analysis indicates that multiple fluid dynamics events are responsible for efficient *** and pressure release can generate normal force for *** velocity gradient-induced viscous shear stress,the turbulence-induced Reynolds shear stress,and shear effects stemmed from turbulence and flow channel-induced collisions can generate lateral force for exfoliation,resulting in theses bulk layered materials self-exfoliation down to single or few layers through their intrinsically lateral self-lubricating ability.

关键词：流体动力学类似物石墨生产透射电子显微镜分析原子力显微镜层状材料剪切应力

Exact Inference for Joint Type-I Hybrid Censoring Model with Exponential Competing Risks Data

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Acta Mathematicae Applicatae Sinica 2017年第3期33卷 645-658页

作者： SONG MAO yi-min SHI Xiao-lin WANG Department of Economics and Management Shanxi UniversityTaiyuan 030006China Department of Applied Mathematics Northwestern Polytechnical UniversityXi'an 710072China 78020 Unit Kunming 655000China

Assuming that the failure time under different risk factors follows the independent exponential distribution, a joint model under Type-I hybrid censoring is addressed in detail. Based on the Maximum likelihood estimates （MLEs） of unknown parameters, we obtain exact distributions of MLEs by using the moment generating function （MGF）. Confidence intervals （CIs） of parameters are constructed through both the exact method and the parametric bootstrap method. Then we compare the performances of different methods by Monte Carlo simulations. Finally, the validity of the proposed models and methods are demonstrated by a numerical example.

关键词： Joint Type-I hybrid censoring Competing causes Moment generating function Likelihood inference Bootstrap methods.

Research on Improved Dark Channel Dehazing Algorithm Based on Parameter Differentiating Sky Area 32

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Research on Improved Dark Channel Dehazing Algorithm Based o...

Generalized Quantum Two-Qutrit-State Splitting

第32届中国控制与决策会议

作者： Liu Tao Liu yi-min School of information Science and Engineering Wuhan University of Science and Technology

ISBN: (数字)9781728158556

ISBN: (纸本)9781728158563

For the dark channel prior defogging algorithm, there are problems such as sky region distortion and darkening of the restored image. An optimization method based on parameter to distinguish between sky and non-sky regions is discussed. First, correct the rough transmittance estimation method for the bright area of the sky. Then, discuss the effectiveness of the distinction between the sky and the sky region by and tolerance parameter K. Estimate the rough transmittance of the sky and non-sky regions separately. And it is refined by adaptive median filtering and guided filtering. Finally, the atmospheric light values estimated by the quadtree subspace partitioning method and the variogram are respectively substituted into the atmospheric scattering model to compare the advantages and disadvantages of the restored image effect. The Experiments prove that the algorithm in this paper has the advantages of strong robustness, can cope with complex scenes, and maintain the normal color of the sky area after defogging, especially compared with the existing methods. Improved the defogging ability and visual effect.

关键词： Image defogging Dark channel prior Transmittance Sky region distortion

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Communications in Theoretical Physics 2008年第10期50卷 873-878页

作者： YUAN Hao LIU yi-min ZHANG Zhan-Jun School of Physics ＆ Material Science Anhui University Hefei 230039 China Department of Physics Shaoguan University Shaoguan 512005 China

A three-party scheme for splitting an arbitrary unknown two-qutrit state is proposed,where two non-maximally-entangled three-qutrit states are taken as the quantum channel among three *** the sender'shelp,if and only if both receivers collaborate together,they can securely share the quantum state in a probabilisticway by introducing an ancilla qutrit and performing appropriate unitary *** relation between the successprobability and coefficients characterizing the quantum channel is *** security of the present scheme is analyzedand ***,the generalization of the three-party scheme to more-party case is also sketched.

关键词： generalized quantum state splitting partially entangled state generalized Bell-state measurement single-qutrit projective measurement

The protective role of tacrine and donepezil in the retina of acetylcholinesterase knockout mice

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 884-890页

作者： Yun-min yi Li Cai yi Shao Man Xu Jing-Lin yi Affiliated Eye Hospital of Nanchang University Jiangxi Research Institute of Ophthalmology and Visual Sciences Department of Ophthalmology the First Affiliated Hospital of Nanchang University

AIM: To determine the effect of different concentrations of the acetylcholinesterase (AChE) inhibitors tacrine and donepezil on retinal protection in AChE(+/-) mice (AChE knockout mice) of various ages. METHODS: Cultured ARPE -19 cells were treated with hydrogen peroxide (H2O2) at concentrations of 0, 250, 500, 1000 and 2000 mu mol/L and protein levels were measured using Western blot. Intraperitoneal injections of tacrine and donepezil (0.1 mg/mL, 0.2 mg/mL and 0.4 mg/mL) were respectively given to AChE4- mice aged 2mo and 4mo and wild-type S129 mice for 7d; phosphate buffered saline (PBS) was administered to the control group. The mice were sacrificed after 30d by cardiac perfusion and retinal samples were taken. AChE(+/-) deficient mice were identified by polymerase chain reaction (PCR) analysis using specific genotyping protocols obtained from the Jackson Laboratory website. H&E staining, immunofluorescence and Western blot were performed to observe AChE protein expression changes in the retinal pigment epithelial (RPE) cell layer. RESULTS: Different concentrations of H2O2 induced AChE expression during RPE cell apoptosis. AChE(+/-) mice retina were thinner than those in wild -type mice (P0.05). CONCLUSION: in viva, tacrine and donepezil can inhibit the expression of AChE; the decrease of AChE expression in the retina is beneficial for the development of the retina.

关键词： retinal pigment epithelium acetylcholinesterase apoptosis AChE(+/-) animal models acetylcholinesterase inhibitors

Theoretical study on magnetocaloric effect and its electric-field regulation in CrI_(3)/metal heterostructure

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 134-141页

作者： Weiwei He Ziming Tang Qihua Gong min yi Wanlin Guo State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China

The extraordinary properties of a heterostructure by stacking atom-thick van der Waals(vdW)magnets have been extensively ***,the magnetocaloric effect(MCE)of heterostructures that are based on monolayer magnets remains to be ***,we deliberate MCE of vd W heterostructure composed of a monolayer CrI_(3)and metal atomic layers(Ag,Hf,Au,and Pb).It is revealed that heterostructure engineering by introducing metal substrate can improve MCE of CrI_(3),particularly boosting relative cooling power to 471.72μJ m^(-2)and adiabatic temperature change to 2.1 K at 5 T for CrI_(3)/*** improved MCE is ascribed to the enhancement of magnetic moment and intralayer exchange coupling in CrI_(3)due to the CrI_(3)/metal heterointerface induced charge *** field is further found to tune MCE of CrI_(3)in heterostructures and could shift the peak temperature by around 10 K in CrI_(3)/Hf,thus manipulating the working temperature window of *** theoretical results could enrich the research on low-dimensional magnetocaloric materials.

关键词： magnetocaloric effect heterostructure metal substrate

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Structural behavior of F-in mould flux melt of CaO-SiO2-Al2 O3-Na2O-CaF2 system

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Journal of Iron and Steel Research International 2017年第11期24卷 1152-1158页

作者： Qiang Gao yi min Cheng-jun Liu Mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic mineral(ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The influence of fluorine on the structure of CaO Si（）e-Al2Oa Na2O-CaF2 continuous-casting-type slag was measured by Raman spectroscopy, and the degree of polymerization of mould flux and the structural behavior of F- in the melt were investigated by classifying and quantifying the structural species of F ions. The results exhibit that the main structural units of Si O tetrahedra are Q1, Q1 and Q2, and the actual measured number of non bridging oxygen ions in the [SiO4 ]-tetrahedra （denoted by NBO/T） in creases from 2. 73 to 3.44 with increasing the molar ratio of F to （F＋O）（denoted by XF/X（F-O ） from 0.06 to 0. 19. It means that the degree of polymerization o1 meh structure decreases with an increase in XE/X（F＋O）. In addition, most of F- ions were distributed in Si-O tetrahedra and Al-O tetrahedra. With increasing XF/X（F＋O）, the complex structural units Al-Otetrahedra are gradually replaced hy discrete structural units A1F4 because of the breakage of Al-O bonds in Al-Otetrahedra by F ions, and the SiO （bridging oxygen） bonds of SiO tetrahedra are broken to form [SiOnF1-n]-tetrahedra by F ions coordinating with Si4 ＋ .

关键词： Mould flux F- ion Melt structure Polymerization degree

Effect of continuous casting speed on mold surface flow and the related near-surface distribution of non-metallic inclusions

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International Journal of minerals,Metallurgy and Materials 2019年第2期26卷 186-193页

作者： Peng Fei yi min Cheng-jun Liu Mao-fa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic mineral ((ministry of Education)) School of Metallurgy Northeastern University Key Laboratory for Ecological Metallurgy of Multimetallic mineral (ministry of Education)

For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. The results show that, at casting speeds of 0.8 and 1.0 m/min, a thin liquid mold flux layer forms and non-uniform floating of argon bubbles occurs, inducing the entrainment and subsequent entrapment of the liquid flux; fine inclusion particles of Al_2O_3 can also aggregate at the solidification front. At higher casting speeds of 1.4 and 1.6 m/min, the liquid mold flux can be entrained and carried deeper into the liquid steel pool because of strong level fluctuations of the liquid steel and the flux. The optimal casting speed is approximately 1.2 m/min, with the most favorable surface flow status and, correspondingly, the lowest number of inclusions near the slab surface.

关键词： non-metallic inclusions distribution casting speed surface flow