检索结果-南通市图书馆

Acta Mathematica sinica,English series 2016年第9期32卷 1035-1074页

作者： Xing FU Ji man ZHAO school of Mathematical sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 P. R. China

Let （x, d,u） be a metric measure the upper doubling conditions. Under the weak space satisfying both the geometrically doubling and reverse doubling condition, the authors prove that the generalized homogeneous Littlewood-Paley g-function gr （r ∈ [2, ∞）） is bounded from Hardy space H1（u） into L1（u）. Moreover, the authors show that, if f ∈ RBMO（u）, then [gr（f）]r is either infinite everywhere or finite almost everywhere, and in the latter case, [gr（f）]r belongs to RBLO（u） with the norm no more than ｜｜f｜｜ RBMO（u） multiplied by a positive constant which is independent of f. As a corollary, the authors obtain the boundedness of gr from RBMO（u） into RBLO（u）. The vector valued Calderon-Zygmund theory over （X, d, u） is also established with details in this paper.

关键词： Non-homogeneous metric measure space generalized homogeneous Littlewood-Paley g-function Hardy space RBMO(u) RBLO(u) vector valued Calderon Zygmund theory

Damage effect analysis and experiment for electronic equipment in impact vibration environment

在线全文

学校读者我要写书评

暂无评论

Journal of systems Engineering and Electronics 2009年第6期20卷 1384-1388页

作者： shi Quan Tian Juan man Qiang Dept. of management Engineering Shijiazhuang Mechanical Engineering Coll. Shijiazhuang 050003 P. R. China

This paper analyzes the electronic equipment＇s effect factors such as structure characteristics and *** radar equipment is taken as an experimental *** damage laws of electro-products in vibration environment are *** experiment shows that the damage of electro-products in vibration environment has relations with both the type and amplitude of vibration and their structure.

关键词： electro-product vibration environment damage effect.

Littlewood–Paley Operators on spaces with Variable Exponent on Homogeneous Groups

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica sinica,English series 2020年第5期36卷 535-558页

作者： Dong Li LIU Ji man ZHAO Key Laboratory of Mathematics and Complex systems Ministry of Education Institution of Mathematics and Mathematical Education School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,on homogeneous groups,we study the Littlewood–Paley operators in variable exponent ***,we prove that the weighted Littlewood–Paley operators are controlled by the weighted Hardy–Littlewood maximal function,and obtain the vector-valued inequalities of the Littlewood–Paley operators,including the Lusin function,Littlewood–Paley g function and gλ* ***,we prove the boundedness of multilinear Littlewood–Paley gψ,λ* function.

关键词： Littlewood–Paley operators variable Lebesgue spaces homogeneous groups

Emerging roles of astrocytes in blood-brain barrier disruption upon amyloid-beta insults in Alzheimer's disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第9期18卷 1890-1902页

作者： Qian Yue Maggie Pui man Hoi state Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao Special Administrative RegionChina Department of Pharmaceutical sciences Faculty of Health SciencesUniversity of MacaoMacao Special Administrative RegionChina

Blood-brain barrier disruption occurs in the early stages of Alzheimer’s *** studies indicate a link between blood-brain barrier dysfunction and cognitive decline and might accelerate Alzheimer’s disease *** are the most abundant glial cells in the central nervous system with important roles in the structural and functional maintenance of the blood-brain *** example,astrocytic cove rage around endothelial cells with perivascular endfeet and secretion of homeostatic soluble factors are two major underlying mechanisms of astrocytic physiological *** activation is often observed in Alzheimer’s disease patients,with astrocytes expressing a high level of glial fibrillary acid protein detected around amyloid-beta plaque with the elevated phagocytic ability for *** alte rations in Alzheimer’s disease astrocytes including swollen endfeet,somata shrinkage and possess loss contribute to disruption in vascular integrity at capillary and arte rioles *** addition,Alzheimer’s disease astrocytes are skewed into proinflammatory and oxidative profiles with increased secretions of vasoactive mediators inducing endothelial junction disruption and immune cell *** this review,we summarize the findings of existing literature on the relevance of astrocyte alte ration in response to amyloid pathology in the context of blood-brain barrier ***,we briefly describe the physiological roles of astrocytes in blood-brain barrier ***,we review the clinical evidence of astrocyte pathology in Alzheimer’s disease patients and the preclinical evidence in animal and cellular *** further discuss the structural changes of blood-brain barrier that correlates with Alzheimer’s disease ***,we evaluate the roles of soluble factors secreted by Alzheimer’s disease astrocytes,providing potential molecular mechanisms underlying blood-brain barrier *** conclude with a

关键词： Alzheimer’s disease amyloid-beta astrocyte(astroglial)-endothelial interaction astrocyte pathology blood-brain barrier blood-brain barrier disruption brain endothelial cell neuroinflammation reactive astrocyte

self-normalized Cramer-type Moderate Deviations for Functionals of Markov Chain

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae sinica 2020年第2期36卷 294-313页

作者： Xin-wei FENG Qi-man sHAO Zhongtai securities Institute for Financial studies Shandong UniversityJinan 250100China Department of statistics The Chinese University of Hong KongShatinN.T.Hong KongChina Department of statistics and Data science Southern University of Science and TechnologyShenzhen 518000China

Let{xn,n≥0}be a Markov chain with a countable state space s and let f(·)be a measurable function from s to R and consider the functionals of the Markov chain yn:=f(xn).We construct a new type of self-normalized sums based on the random-block scheme and establish a Crame′r-type moderate deviations for self-normalized sums of functionals of the Markov chain.

关键词： self-normalized partial sums Cramer-type moderate deviations Markov Chain ergodic

Field estimation of maize plant height at jointing stage using an RGB-D camera

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2022年第5期10卷 1274-1283页

作者： Ruicheng Qiu man Zhang Yong He College of Biosystem Engineering and Food science Zhejiang UniversityHangzhou 310058ZhejiangChina Key Laboratory of Modern Precision Agriculture system Integration Research Ministry of EducationChina Agricultural UniversityBeijing 100083China

Plant height can be used for assessing plant vigor and predicting biomass and yield. manual measurement of plant height is time-consuming and labor-intensive. We describe a method for measuring maize plant height using an RGB-D camera that captures a color image and depth information of plants under field conditions. The color image was first processed to locate its central area using the s component in HsV color space and the Density-Based spatial Clustering of Applications with Noise algorithm. Testing showed that the central areas of plants could be accurately located. The point cloud data were then clustered and the plant was extracted based on the located central area. The point cloud data were further processed to generate skeletons, whose end points were detected and used to extract the highest points of the central leaves. Finally, the height differences between the ground and the highest points of the central leaves were calculated to determine plant heights. The coefficients of determination for plant heights manually measured and estimated by the proposed approach were all greater than 0.95. The method can effectively extract the plant from overlapping leaves and estimate its plant height. The proposed method may facilitate maize height measurement and monitoring under field conditions.

关键词： Maize plant heigh Kinect Maize central area Point cloud data Image processing

A Wiener-Hopf factorization related potential measure for spectrally negative Lévy process

在线全文

学校读者我要写书评

暂无评论

Frontiers of Mathematics in China 2021年第2期16卷 325-343页

作者： man CHEN Xianyuan WU Xiaowen ZHOU school of Mathematical sciences Capital Normal UniversityBeijing 100048China Department of Mathematics and statistics Concordia UniversityMontrealQC H3G 1M8Canada

For spectrally negative Lévy process (sNLP), we find an expression, in terms of scale functions, for a potential measure involving the maximum and the last time of reaching the maximum up to a draw-down time. As applications, we obtain a potential measure for the reflected sNLP and recover a joint Laplace transform for the Wiener-Hopf factorization for sNLP.

关键词： spectrally negative Lévy process(sNLP) potential measure draw-down time excursion theory scale function Wiener-Hopf factorization

Experimental investigation of the interaction between a pulsating bubble and a rigid cylinder

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica sinica 2013年第4期29卷 503-512页

作者： A-man Zhang Wei Xiao shi-Ping Wang College of shipbuilding Engineering Harbin Engineering University

In this paper, the behavior of a bubble near a rigid cylinder is studied experimentally as the positions of bubble induction change, and several cylinders with different diam- eters are used in the experiment. The main results are as follows. The behavior of a bubble near a rigid cylinder is distinct from that near a rigid plate. When the cylinders are laid in deep water, there will occur three kinds of typical bubble shapes as the distance between bubble and cylinder increases. And the bubble shapes are different as the diam- eter of cylinder varies. When the cylinders are laid near a free surface, the behaviors of bubble near cylinders with dif- ferent diameters are similar. For a certain distance between bubble and free surface, as the distance between bubble and cylinder increases, ＂double jet＂, ＂inclined jet＂ and ＂down- ward jet＂ will take place successively.

关键词： Bubble ~ Cylinder. Electric spark- Free sur-face ~ Jet

Advances in theoretical study on transition-metal-catalyzed C-H activation

在线全文

学校读者我要写书评

暂无评论

science China Chemistry 2016年第11期59卷 1448-1466页

作者： Yuan-Ye Jiang Xiaoping man siwei Bi school of Chemistry and Chemical Engineering Qufu Normal University

Transition-metal-catalyzed C–H activation represents one of most attractive research fields in modern organic chemistry while theoretical studies have become a popular and effective tool for elucidating mechanism nowadays. The recent achievements in the cross field of the two orientations are reviewed in this article. The first part introduced the advances in theoretical study on transition-metal-catalyzed C–H activation. The elegant work reported mainly in and after 2013, classified according to the mechanisms of C–H activation, were covered. The second part provided an analysis on the distribution of quantum-chemical methods, solvation models and basis sets in the collected theoretical studies.

关键词： transition metal C–H activation mechanism DFT

Application of discrete artificial bee colony algorithm for cloud task optimization scheduling

在线全文

学校读者我要写书评

暂无评论

International Journal of Modeling, simulation, and scientific Computing 2020年第4期11卷 190-200页

作者： shuai man Rongjie Yang Langfang Health Vocational College Langfang Hebei 065000P.R.China

The performance of task scheduling algorithm in cloud computing determines the performance of the cloud *** study mainly analyzed the application of the artificial bee colony(ABC)algorithm in the cloud task *** order to solve the problem of cloud task scheduling,the ABC algorithm was discretized to get the discrete artificial bee colony(DABC)*** the mathematical model of cloud task scheduling was established and solved by the DABC ***,the simulation experiment was carried out,and the performance of first-come-first-served(FCFs),MIN–MIN,ABC and DABC algorithms under different cloud tasks was compared to verify the performance of the proposed *** results showed that the user waiting time of the DABC algorithm was 1210s,the load balance degree was 0.01,and the user payment fee was 1688 yuan when the number of cloud tasks was 500;compared with other algorithms,the user waiting time of the DABC algorithm was shorter,the resource load balance degree was higher,and the overall performance was *** research results verify the effectiveness of the DABC algorithm in solving the problem of cloud task optimal scheduling,and it can be further extended and applied in practice.

关键词： Cloud task scheduling artificial bee colony algorithm optimization method cloud computing.