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RESEARCH ON AMSAA-BISE MODEL—AN ANSWER TO MEI MEN-HUA

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Applied Mathematics and Mechanics(English Edition) 2001年第7期22卷 856-861页

作者： zhou Yuan-quan(周源泉) Beijing Institute of Structure and Environment Engineering Beijing 100076 P R China

The AMSAA-BISE model is derived from another approach. This certainly shows the correctness of the AMSAA-BISE model, and indicates the incorrectness of the approximate model given in this paper. The engineering exampl... 详细信息

关键词： Reliability theory

Distributed Contact Plan Design for Multi-Layer Satellite-Terrestrial Network

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China Communications 2018年第1期15卷 23-34页

作者： Wenfeng Shi Deyun Gao Huachun zhou Bohao feng Haifeng Li Guanwen Li Wei quan School of Electronic and Information Engineering Beijing Jiaotong University

In multi-layer satellite-terrestrial network, Contact Graph Routing(CGR) uses the contact information among satellites to compute routes. However, due to the resource constraints in satellites, it is extravagant to configure lots of the potential contacts into contact plans. What's more, a huge contact plan makes the computing more complex, which further increases computing time. As a result, how to design an efficient contact plan becomes crucial for multi-layer satellite network, which usually has a large scaled topology. In this paper, we propose a distributed contact plan design scheme for multi-layer satellite network by dividing a large contact plan into several partial parts. Meanwhile, a duration based inter-layer contact selection algorithm is proposed to handle contacts disruption problem. The performance of the proposed design was evaluated on our Identifier/Locator split based satellite-terrestrial network testbed with 79 simulation nodes. Experiments showed that the proposed design is able to reduce the data delivery delay.

关键词： contact graph routing distributedcontact plan multi-layered satellite network inter-layer contact selection

Whole-brain CT Perfusion at Admission and During Delayed Time-window Detects the Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage

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Current Medical Science 2023年第2期43卷 409-416页

作者： feng YOU Wen-juan TANG Chao ZHANG Ming-quan YE Xing-gen FANG Yun-feng zhou Department of Radiology the First Affiliated Hospital of Wannan Medical CollegeWuhu241001China Department of Radiology Affiliated Hangzhou First People’s HospitalHangzhou310000China Department of Radiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China School of Medical Information Wannan Medical CollegeWuhu241001China Department of Neurosurgery the First Affiliated Hospital of Wannan Medical CollegeWuhu241001China

Objective To evaluate the utility of computed tomography perfusion(CTP)both at admission and during delayed cerebral ischemia time-window(DCITW)in the detection of delayed cerebral ischemia(DCI)and the change in CTP parameters from admission to DCITW following aneurysmal subarachnoid *** Eighty patients underwent CTP at admission and during *** mean and extreme values of all CTP parameters at admission and during DCITW were compared between the DCI group and non-DCI group,and comparisons were also made between admission and DCITW within each *** qualitative color-coded perfusion maps were ***,the relationship between CTP parameters and DCI was assessed by receiver operating characteristic(ROC)*** With the exception of cerebral blood volume(P=0.295,admission;P=0.682,DCITW),there were significant differences in the mean quantitative CTP parameters between DCI and non-DCI patients both at admission and during *** the DCI group,the extreme parameters were significantly different between admission and *** DCI group also showed a deteriorative trend in the qualitative color-coded perfusion *** the detection of DCI,mean transit time to the center of the impulse response function(Tmax)at admission and mean time to start(TTS)during DCITW had the largest area under curve(AUC),0.698 and 0.789,*** Whole-brain CTP can predict the occurrence of DCI at admission and diagnose DCI during *** extreme quantitative parameters and qualitative color-coded perfusion maps can better reflect the perfusion changes of patients with DCI from admission to DCITW.

关键词： aneurysmal subarachnoid hemorrhage delayed cerebral ischemia admission time window computed tomography perfusion

Uniform zinc deposition on O,N-dual functionalized carbon cloth current collector

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Journal of Energy Chemistry 2022年第6期31卷 76-83,I0003页

作者： Mengqi zhou Guoqiang Sun Shuang-quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis CenterCollege of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina

The society’s urgent demand for environmentally friendly, safe and low-cost energy storage devices has promoted the research of aqueous zinc-ion batteries. However, the uneven deposition of Zn ions on anodes will lead to the growth of the dendrite and reduce the Coulombic efficiency as well as the lifespan of the devices. Herein, we construct an O,N-dual functionalized carbon cloth current collector via a simple hydrothermal strategy, in which the oxygen-containing functional groups and the N heteroatoms can regulate the transmission and deposition of Zn ions, respectively. The proposed synergistic strategy ensures the uniform distribution of Zn ions on the surface of the Zn anode and inhibits the formation of dendrites. The symmetric cell based on the O,N-dual doped carbon cloth presents superior cycling stability(318 h) with a low voltage hysteresis(11.2 mV) at an areal capacity of 1 m Ah cm^(-2)(20% depth of diacharge). Meanwhile, the appreciably low overpotential(16 m V) and high Columbic efficiency(98.2%)also demonstrate that the O,N-dual functionalized carbon cloth can be worked as a promising host for Zn ions deposition.

关键词： O N-dual functionalized carbon cloth Synergistic strategy Long cycle life Low overpotential Dendrite-free Zn anode

Liouville type theorems for Schrdinger systems

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Science China Mathematics 2015年第1期58卷 179-196页

作者： ZHUO Ran LI feng quan Department of Mathematical Sciences Yeshiva University School of Mathematical Sciences Dalian University of Technology

We study positive solutions to the following higher order SchrSdinger system with Dirichlet boundary conditions on a half space： where a is any even number between 0 and n. This PDE system is closely related to the integral system where G is the corresponding Green＇s function on the half space. More precisely, we show that every solution to （0.2） satisfies （0.1）, and we believe that the converse is also true. We establish a Liouville type theorem the non-existence of positive solutions to （0.2） under a very weak condition that u and v are only locally integrable. Some new ideas are involved in the proof, which can be applied to a system of more equations.

关键词： Schrodinger systems poly-harmonic operators Dirichlet boundary conditions method of movingplanes in integral forms Kelvin transforms monotonicity rotational symmetry non-existence

Regular Balanced Cayley Maps for Cyclic,Dihedral and Generalized Quaternion Groups

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Acta Mathematica Sinica,English Series 2005年第4期21卷 773-778页

作者： Yan WANG Rong quan feng Department of Mathematics Yan Tai University Yan Tai 264005. P. R. China LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

A Cayley map is a Cayley graph embedded in an orientable surface such that. the local rotations at every vertex are identical. In this paper, balanced regular Cayley maps for cyclic groups, dihedral groups, and genera... 详细信息

关键词： Map Cayley map Regular Balanced

Infrared optical coatings in SITP

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光学精密工程 2005年第4期13卷 483-486页

作者： LIU Ding-quan ZHANG feng-shan Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

Infrared optical coatings in SITP (Shanghai Institute of Technical Physics) mainly cover the spectrum range from 0.7 μm to 15 μm, and visible and near-UV range are also been included. The coatings are mainly used for metal-reflectance mirrors, Anti-reflection(AR) lens and windows, filters, and dichroic beam splitters. Coatings passed some dependability tests. These optical coated devices usually consist in a remote observing instrument. Most coating materials are commercial products. And one kind of special material PbTe is made by ourselves. Some main results of our research department are reported.

关键词：上海物理研究所光学涂覆技术红外线光谱

Hitting Probabilities and the Hausdorff Dimension of the Inverse Images of a Class of Anisotropic Random Fields

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Acta Mathematica Sinica,English Series 2015年第12期31卷 1895-1922页

作者： Zhen Long CHEN quan zhou School of Statistics and Mathematics Zhejiang Gongshang University

Let X = {X（t）：t ∈ R^N} be an anisotropic random field with values in R^*** certain conditions on X,we establish upper and lower bounds on the hitting probabilities of X in terms of respectively Hausdorff measure and Bessel-Riesz *** also obtain the Hausdorff dimension of its inverse image,and the Hausdorff and packing dimensions of its level *** results are applicable to non-linear solutions of stochastic heat equations driven by a white in time and spatially homogeneous Gaussian noise and anisotropic Guassian random fields.

关键词： Anisotropic random field non-linear stochastic heat equations spatially homogeneous Gaussian noise hitting probabilities Hausdorff dimension inverse image

A REMARK ON DUALITY FOR THE SUM OF CONVEX FUNCTIONS IN GENERAL BANACH SPACES

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Chinese Annals of Mathematics,Series B 1998年第3期19卷 249-254页

作者： zhou feng Department of Mathematics East China Normal University Shanghai 200062 China

The author gives a new proof of Attouch Brezis′ theorem concerned with the duality for the sum of convex functions in general Banach spaces, and gives also some sufficient conditions for the difference of two close... 详细信息

关键词： Conjugate convex function Asymptotic cone Infimal convolution