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Revisiting the Model of Servicing Machines with Repairable Service Facility-A New Analyzing Idea and Some New Results

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Acta Mathematicae Applicatae Sinica 2010年第4期26卷 557-566页

作者： ying-hui Tang School of Fundamental Education Sichuan Normal UniversityChengdu 610066China School of Mathematics and Software Science Sichuan Normal UniversityChengdu 610066China

In this paper the model of servicing machines with repairable facility is further *** standard conditioning decomposition argument,two reliability indices-the probability that the service facility fails at time t and the expected number of failure occurring during（0,t] are *** important relations of them are ***,some new reliability problems are presented and discussed as follows：1） The numbers of the service facility failures during the generalized service time and the generalized busy period;2） The asymptotic expansion of the expected failure number of the service facility during（0,t].A series of new reliability results of the service facility are obtained.

关键词： Repairable service facility reliability index failure number breakdown

Zero Dissipation Limit to Rarefaction Waves for the p-System

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1229-1240页

作者： hui ying WANG Center of Mathematical Science Zhejiang University Hangzhou 310027 P. R. China

We study the zero-dissipation problem for a one-dimensional model system for the isentropic flow of a compressible viscous gas, the so-called p-system with viscosity. When the solution of the inviscid problem is a rarefaction wave with finite strength, there exists unique solution to the viscous problem with the same initial data which converges to the given inviscid solution as c goes to zero. The proof consists of a scaling argument and elementary energy analysis, based on the underlying wave structure.

关键词： Zero dissipation problem p-system Centered rarefaction wave

Ruin probability for correlated negative risk sums model with Erlang processes

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Applied Mathematics(A Journal of Chinese Universities) 2009年第1期24卷 14-20页

作者： DONG ying-hui Department of Mathematics Suzhou Technology University Suzhou 215011 China Department of Mathematics Suzhou University Suzhou 215006 China

This paper studies a Sparre Andersen negative risk sums model in which the distribution of ＂interclaim＂ time is that of a sum of n independent exponential random variables. Thus, the Erlang（n） model is a special case. On this basis the correlated negative risk sums process with the common Erlang process is considered. Integro-differential equations with boundary conditions for ψ（u） are given. For some special cases a closed-form expression for ψ（u） is derived.

关键词： ruin probability Erlang process correlated negative risk sums process equation

Effects of pairing correlation on neutron drop

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 88-97页

作者： ying-hui Ge ying Zhang Jin-Niu Hu Department of Physics School of ScienceTianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China

In this work, the effects of the pairing correlation on the properties of neutron drops N=6-50 trapped in a harmonic oscillator potential with ω = 10 Me V are investigated by comparing the results given by the Skyrme Hartree-Fock and Hartree-FockBogoliubov theories with the density-dependent delta interaction(DDDI) pairing force. The results showed that the pairing correlation slightly made the neutron drops more bound, and increased the central neutron density, the spin-orbit and pseudo spin-orbit splittings. Thus, the pairing correlation must be accounted for to improve the Skyrme functional compared with the ab initio calculations. Furthermore, although the single-particle energy gaps with or without pairing were similar, the shell closures varied due to pair scattering. Here, the shell closures in neutron drops using the Sk M* parameter set and DDDI pairing force were found at N=8, 16, and 32.

关键词： neutron drop Hartree-Fock theory Hartree-Fock-Bogoliubov theory pairing correlation

Effect of solution treatment on the martensitic transformation behavior of a Ni_(43)Co_7Mn_(39)Sn_(11) polycrystalline alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 620-626页

作者： Zhi-gang Wu hui-ying Li Frontier Institute of Science and Technology Xi'an Jiaotong University

The effect of solution treatment on the martensitic transformation behavior of a Ni43Co7Mn39Sn11 polycrystalline alloy fabricated by an arc melting method was investigated by scanning electron microscopy（SEM）, energy-dispersive X-ray spectroscopy（EDS）, and differential scanning calorimetry（DSC）. The examination indicates the presence of severe chemical segregation in the dendritic as-cast structure because of solidification. This chemical segregation completely impedes the intrinsic martensitic transformation. Annealing at 1223 K for 24 h is identified as the threshold annealing condition to eliminate the microstructural segregation and begin the martensitic transformation, as indicated by a broad and obscure feature. Annealing at 1273 K for 24–48 h is found to be effective at promoting notably the martensitic transformation, but the martensitic transformation exhibits a multiple-step feature. Complete homogeneity is achieved by annealing at 1273 K for 72 h, which produces a sharp, single-step martensitic transformation. The microstructural evolution and the valence electron concentrations of alloys（e/a ratio） are evaluated, which are reflective of the degree of compositional homogeneity of alloys, confirming that high annealing temperature and long holding time are vital to reveal the intrinsic martensitic behavior of this alloy. The adequately homogenized alloy displays a martensitic transformation at 292 K and an enthalpy of 11.2 J/g.

关键词： shape memory alloys annealing martensitic transformations homogeneity

Coarsening behavior of MX carbonitrides in type 347H heat-resistant austenitic steel during thermal aging

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International Journal of Minerals,Metallurgy and Materials 2016年第3期23卷 283-293页

作者： ying-hui Zhou Chen-xi Liu Yong-chang Liu Qian-ying Guo hui-jun Li State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and Engineering Tianjin University

In this work, the growth kinetics of MX （M - metal, X - C/N） nanoprecipitates in type 347H austenitic steel was systematically studied. To investigate the coarsening behavior and the growth mechanism of MX carbonitrides during long-term aging, experiments were performed at 700, 800, 850, and 900℃ for different periods （1, 24, 70, and 100 h）. The precipitation behavior of carbonitrides in specimens subjected to various aging conditions was explored using carbon replicas and transmission electron microscopy （TEM） observations. The corresponding sizes ofMX carbonitrides were measured. The results demonstrates that MX carbonitrides precipitate in type 347H austenitic steel as Nb（C,N）. The coarsening rate constant is time-independent; however, an increase in aging temperature results in an increase in coarsening rate of Nb（C,N）. The coarsening process was analyzed according to the calculated diffusion activation energy of Nb（C,N）. When the aging temperature was 800-900℃, the mean activation energy was 294 kJ·mol -1, and the coarsening behavior was controlled primarily by the diffusion of Nb atoms.

关键词： austenitic steel heat resistance carbonitrides coarsening nanoparticles diffusion thermal aging

15%Efficiency All-Polymer Solar Cells Based on a Polymer Acceptor Containing B←N Unit

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Chinese Journal of Polymer Science 2022年第8期40卷 989-995,I0011页

作者： ying-Ze Zhang Ning Wang ying-hui Wang Jun-hui Miao Jun Liu Li-Xiang Wang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

The development of new polymer acceptors strongly paves the power conversion efficiency(PCE)improvement of all polymer solar cells(all-PSCs).Herein,we develop a new polymer acceptor PBN26,which is the alternating copolymer of 2,2′-((2Z,2′Z)-((12,13-bis(2-octyldodecyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2″,3″:4′,5′]thieno[2′,3′:4,5]pyrrolo[3,2-g]thieno[2′,3′:4,5]thieno[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro-1 H-indene-2,1-diylidene))dimalononitrile and B←N bridged thienylthiazole(BNTT).The optimized all-PSCs device based on PBN26 exhibits a PCE of 15.09%,which is the highest value of the all-PSCs based on B←N-based polymer acceptors at ***,we also fabricate an all-PSC module with active area of 10 cm2 by blade coating,which exhibits a PCE of 8.78%.These results prove that polymer acceptors containing B←N units are promising for all-PSC device applications.

关键词： Organic photovoltaic All-polymer solar cells Polymer acceptors Boron-nitrogen coordination bond

Shape Optimization in Two-Dimensional Viscous Compressible Fluids

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1793-1806页

作者： Zhong TAN ying hui ZHANG School of Mathematical Sciences Xiamen University Xiamen 361005 P. R. China Department of Mathematics Hu'nan Institute of Science and Technology Yueyang 414006 P. R. China

We present a method for solving the optimal shape problems for profiles surrounded by viscous compressible fluids in two space dimensions. The class of admissible profiles is quite general including the minimal volume condition and a constraint on the thickness of the boundary. The fluid flow is modelled by the Navier-Stokes system for a general viscous barotropic fluid with the pressure satisfying p（o） = aQlog^d（o） for large Q. Here d 〉 1 and a 〉 0.

关键词： Optimization shape Orlicz spaces Navier-Stokes equations

Blow-up of Smooth Solutions to the Compressible Fluid Models of Korteweg Type

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Acta Mathematica Sinica,English Series 2012年第3期28卷 645-652页

作者： ying hui ZHANG Zhong TAN Department of Mathematics Hu’nan Institute of Science and Technology School of Mathematical Sciences Xiamen University

We show the blow-up of smooth solutions to a non-isothermal model of capillary compressible fluids in arbitrary space dimensions with initial density of compact support. This is an extension of Xin＇s result [Xin, Z.： Blow-up of smooth solutions to the compressible Navier-Stokes equations with compact density. Comm. Pure Appl. Math., 51, 229-240 （1998）] to the capillary case but we do not need the condition that the entropy is bounded below. Moreover, from the proof of Theorem 1.2, we also obtain the exact relationship between the size of support of the initial density and the life span of the solutions. We also present a sufficient condition on the blow-up of smooth solutions to the compressible fluid models of Korteweg type when the initial density is positive but has a decay at infinity.

关键词： Blow-up smooth solutions capillary compressible fluids compact support