期刊文献+
共找到26,402篇文章
< 1 2 250 >
每页显示 20 50 100
Compactness of Fractional Calderón Type Commutators on Morrey Spaces
1
作者 LI Aobo MEI Ting WEI Qi 《数学进展》 北大核心 2025年第4期858-870,共13页
In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey... In this paper,the authors study the fractional Calderon type commutator T_(Ω,α)^(A)and its maximal operator M_(Ω,α)^(A)with kernels having some kinds of Log-type Dini-condition and obtain the compactness on Morrey spaces L^(p,λ)(R^(n)). 展开更多
关键词 Calderón type commutator compactness Log-type Dini-condition Morrey space
原文传递
TillerPET:High-throughput in-situ phenotyping of rice tiller number and compactness from post-harvest stubble
2
作者 Letian Zhou Zhixin Tang +7 位作者 Songliang Cao Xiaonan Hu Wei Zhou Xuhui Zhu Xiaodong Bai Hao Lu Fan Chen Weijuan Hu 《The Crop Journal》 2025年第6期1928-1938,共11页
For fast in-situ assessment of tiller phenotypes in rice breeding,we introduce the TillerPET model,an improved transformer-based deep learning solution that permits phenotyping the number and compactness of rice tille... For fast in-situ assessment of tiller phenotypes in rice breeding,we introduce the TillerPET model,an improved transformer-based deep learning solution that permits phenotyping the number and compactness of rice tillers in images of post-harvest rice stubble.A rice tiller phenotype dataset covering three years of field data and four experimental sites across China was constructed to train and validate the model.TillerPET reports an R2 of 0.941 for counting tiller number,demonstrating state-of-the-art performance on the proposed RTP dataset.Beyond its minimal errors in estimating tiller number,TillerPET also achieves an R2 of 0.978 for characterizing tiller compactness.The two phenotypic parameters exhibit a high degree of consistency with expert breeders,offering reliable phenotypic indicators to guide further breeding. 展开更多
关键词 Plant phenotyping Rice tillers Tiller compactness Post-harvest stubble Plant counting
在线阅读 下载PDF
WADdiana Compact全自动血型分析仪偶见故障及排除
3
作者 胡菊 郑卫东 《医疗卫生装备》 2025年第1期118-120,共3页
介绍了WADdiana Compact全自动血型分析仪在使用中出现的5例偶见故障,详细分析了故障原因,提出了具体的排除方法,为同行维修类似故障提供了参考。
关键词 WADdiana compact全自动血型分析仪 故障维修 故障排除
在线阅读 下载PDF
A NOTE IN APPROXIMATIVE COMPACTNESS AND MIDPOINT LOCALLY K-UNIFORM ROTUNDITY IN BANACH SPACES 被引量:4
4
作者 刘春燕 张子厚 周宇 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期643-650,共8页
In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A ... In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A Banach space X is midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively compact k-Chebyshev set. 展开更多
关键词 k-Chebyshev set approximatively weak compactness approximative compactness weak midpoint locally k-uniform rotundity midpoint locally k-uniform rotundity k-strict rotundity
在线阅读 下载PDF
Compactness for the commutators of multilinear singular integral operators with non-smooth kernels 被引量:2
5
作者 BU Rui CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第1期55-75,共21页
In this paper, the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered. By some new maximal functions... In this paper, the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered. By some new maximal functions to control the commutators of bilinear singular integral operators and CMO(Rn) functions, compactness for the commutators is proved. 展开更多
关键词 singular integral OPERATOR maximal function weighted norm inequality COMMUTATOR compact OPERATOR
在线阅读 下载PDF
COMPACTNESS FOR THE COMMUTATOR OF BOCHNER-RIESZ OPERATOR 被引量:1
6
作者 卜瑞 陈杰诚 胡国恩 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1373-1384,共12页
Let α ∈0,(n-1)/2 and T~α be the Bochner-Riesz operator of order α. In this paper, for n = 2 and n ≥ 3, the compactness on Lebesgue spaces and Morrey spaces are considered for the commutator of Bochner-Riesz opera... Let α ∈0,(n-1)/2 and T~α be the Bochner-Riesz operator of order α. In this paper, for n = 2 and n ≥ 3, the compactness on Lebesgue spaces and Morrey spaces are considered for the commutator of Bochner-Riesz operator generated by CMO(R^n) function and T~α. 展开更多
关键词 Bochner-Riesz operator COMMUTATOR compact operator Fourier transform estimate
在线阅读 下载PDF
ON COMPACTNESS FOR ITERATED COMMUTATORS 被引量:1
7
作者 刘永民 于燕燕 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期491-500,共10页
The authors study the iterated commutators on the weighted Bergman spaces A2(φ), and prove that Cnh is compact on A2(φ) if and only if h ∈ B0.
关键词 Weighted Bergman space iterated commutator normal function littleBloch function compactness
在线阅读 下载PDF
Measurement and Spatial Distribution of Urban Agglomeration Industrial Compactness in China 被引量:4
8
作者 QI Weifeng FANG Chuanglin SONG Jitao 《Chinese Geographical Science》 SCIE CSCD 2008年第4期291-299,共9页
Urban agglomeration (UA) compactness means spatial concentration degree of physical entities, such as cities (towns), industries, resources, funds, traffic and technologies, whose concentration is formed according to ... Urban agglomeration (UA) compactness means spatial concentration degree of physical entities, such as cities (towns), industries, resources, funds, traffic and technologies, whose concentration is formed according to specified economic and technologic association in the process of UA formation and development. The UA industrial compactness means the concentration degree of industry and industry clusters with reference to the industrial, technologi- cal and economic relations among the cities in the UA in the process of rational industrial division and with the exten- sion of industrial chain. After analyzing the researches on compactness, this paper finds that the relevant measurement coefficient and methods reflecting industrial geographical concentration fail to link industries spatial concentration with urban spatial concentration. Taking 23 UAs as samples and classifying them by development degree, this paper probes into UA compactness and spatial distribution characteristics from the perspective of industry by adopting UA index systems of industry and measurement models. The research finds out: 1) there is obvious positive correlation between UA industrial compactness and UA development degree; 2) the spatial distribution difference of UA industrial compactness is relatively great; and 3) UA industrial compactness shows a gradually decreasing tendency from the eastern part, the middle part to the western part of China. From the research thoughts and approaches, this article suggests that studies on the UA integrated compactness measurement should be enhanced from a multidimensional perspective involving space, traffic, population density and so on. 展开更多
关键词 industrial compactness urban agglomeration(UA) China
在线阅读 下载PDF
STRONG COMPACTNESS OF APPROXIMATE SOLUTIONS TO DEGENERATE ELLIPTIC-HYPERBOLIC EQUATIONS WITH DISCONTINUOUS FLUX FUNCTION 被引量:1
9
作者 Helge Holden Kenneth H. Karlsen +1 位作者 Darko Mitrovic Evgueni Yu. Panov 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1573-1612,共40页
Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux ... Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux vector. The proofs are based on deriving localization principles for H-measures associated to sequences of measurevalued functions. This main result implies existence of solutions to degenerate parabolic convection-diffusion equations with discontinuous flux. Moreover, it provides a framework in which one can prove convergence of various types of approximate solutions, such as those generated by the vanishing viscosity method and numerical schemes. 展开更多
关键词 degenerate hyperbolic-elliptic equation degenerate convection-diffusion equation conservation law discontinuous flux approximate solutions compactness
在线阅读 下载PDF
Degree of Compactness in I-fuzzy Topological Spaces 被引量:1
10
作者 李宏艳 《Northeastern Mathematical Journal》 CSCD 2008年第6期485-491,共7页
In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spac... In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spaces accordingly. 展开更多
关键词 I-fuzzy topology value set of compactness degrees of compactness
在线阅读 下载PDF
EQUI-ATTRACTION AND BACKWARD COMPACTNESS OF PULLBACK ATTRACTORS FOR POINT-DISSIPATIVE GINZBURG-LANDAU EQUATIONS 被引量:1
11
作者 李扬荣 佘连兵 尹金艳 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期591-609,共19页
A new concept of an equi-attractor is introduced, and defined by the minimal compact set that attracts bounded sets uniformly in the past, for a non-autonomous dynam- ical system. It is shown that the compact equi-att... A new concept of an equi-attractor is introduced, and defined by the minimal compact set that attracts bounded sets uniformly in the past, for a non-autonomous dynam- ical system. It is shown that the compact equi-attraction implies the backward compactness of a pullback attractor. Also, an eventually equi-continuous and strongly bounded process has an equi-attractor if and only if it is strongly point dissipative and strongly asymptotically compact. Those results primely strengthen the known existence result of a backward bounded pullback attractor in the literature. Finally, the theoretical criteria are applied to prove the existence of both equi-attractor and backward compact attractor for a Ginzburg-Landau equation with some varying coefficients and a backward tempered external force. 展开更多
关键词 Non-autonomous systems point dissipative processes pullback attractors backward compact attractors equi-attractors Ginzburg-Landau equations
在线阅读 下载PDF
Compactness of Composition Operators from the p-Bloch Space to the q-Bloch Space on the Classical Bounded Symmetric Domains 被引量:1
12
作者 Jianbing Su Huijuan Li +1 位作者 Xingxing Miao Rui Wang 《Advances in Pure Mathematics》 2014年第12期649-664,共16页
In this paper, we introduce the weighted Bloch spaces on the first type of classical bounded symmetric domains , and prove the equivalence of the norms and . Furthermore, we study the compactness of composition operat... In this paper, we introduce the weighted Bloch spaces on the first type of classical bounded symmetric domains , and prove the equivalence of the norms and . Furthermore, we study the compactness of composition operator from to , and obtain a sufficient and necessary condition for to be compact. 展开更多
关键词 BLOCH Space Classical BOUNDED Symmetric Domains Composition Operators compactness BERGMAN Metric
在线阅读 下载PDF
Application of Compactness Detection to Complicated Concrete-Filled Steel Tube by Ultrasonic Method 被引量:3
13
作者 杨建江 王飞 +1 位作者 陆苏亮 王川 《Transactions of Tianjin University》 EI CAS 2014年第2期126-132,共7页
An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concr... An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concrete-filled steel tubular column,the plane detection method and embedded sounding pipe method were adopted in the process of effectively detecting the column.According to the results of the plane detection method and embedded sounding pipe method,the cementing status of steel tube and concrete can be concluded,which cannot be judged by the hammering method in the rectangular steel tube-reinforced concrete. 展开更多
关键词 ultrasonic method concrete-filled steel tube plane detection method embedded sounding pipe method compactness
在线阅读 下载PDF
THE COMPACTNESS OF A KIND OF GENERALIZED HANKEL OPERATORS ON THE BERGMAN SPACE OF THE UNIT BALL 被引量:1
14
作者 罗罗 史济怀 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期471-475,共5页
This paper gives the compactness criteria for a kind of generalized Hankel operators on Bergman spaces Lpa(B) defined by M. M. Peloso.
关键词 Hankel operator compactness Bergman spa?
在线阅读 下载PDF
Study on mechanical properties of soil-rock mixture of various compactness subjected to freeze-thaw cycles 被引量:2
15
作者 Zhong Zhou HaoHui Ding +1 位作者 WenYuan Gao LinRong Xu 《Research in Cold and Arid Regions》 CSCD 2021年第5期450-462,共13页
The soil-rock mixture,a collection of soil particles and rock blocks,is inherently heterogeneous and anisotropic due to significant particle size and material strength differences.This study conducts triaxial tests on... The soil-rock mixture,a collection of soil particles and rock blocks,is inherently heterogeneous and anisotropic due to significant particle size and material strength differences.This study conducts triaxial tests on soil-rock mixture samples of various compactness subjected to varying freeze-thaw cycles.A mesoscopic simulation is carried out by particle flow code(PFC)to analyze the effects of freeze-thaw cycles on the mechanical properties of soil and rock particles.The results show that the mechanical properties of the soil-rock mixture under freeze-thaw cycles are greatly affected by the initial compaction.In general,when the degree of compaction is higher,the influence of freeze-thaw cycles on the soil-rock mixture is greater.The stress-strain curves of the samples with different compactness demonstrate strain-softening behavior.The freeze-thaw cycles greatly influence the failure strength of the samples with a higher degree of compaction but have little impact on the samples with a lower degree of compaction.On the microscopic level,during freeze-thaw cycles,the pore volume in the highly compacted sample is too small to accommodate the volume expansion from ice crystal formation,causing significant strength loss among the soil and rock particles and deterioration of the macroscopic properties of the soil-rock mixture. 展开更多
关键词 soil-rock mixtures freeze-thaw cycle degree of compaction particle flow code
在线阅读 下载PDF
Compactness for Commutator of Fractional Integral on Non-homogeneous Morrey Spaces 被引量:2
16
作者 Guanghui LU 《Journal of Mathematical Research with Applications》 CSCD 2022年第1期73-88,共16页
The aim of this paper is to establish the necessary and sufficient conditions for the compactness of fractional integral commutator[b,I_(γ)]which is generated by fractional integral I_(γ)and function b∈Lip_(β)(μ)... The aim of this paper is to establish the necessary and sufficient conditions for the compactness of fractional integral commutator[b,I_(γ)]which is generated by fractional integral I_(γ)and function b∈Lip_(β)(μ)on Morrey space over non-homogeneous metric measure space,which satisfies the geometrically doubling and upper doubling conditions in the sense of Hytonen.Under assumption that the dominating functionλsatisfies weak reverse doubling condition,the author proves that the commutator[b,I_(γ)]is compact from Morrey space M_(q)^(p)(μ)into Morrey space M_(t)^(s)(μ)if and only if b∈Lip_(β)(μ). 展开更多
关键词 non-homogeneous metric measure space compactness commutator of fractional integral Lipβ(μ) Morrey space
原文传递
Measurement and Spatial Distribution of Urban Land Use Compactness in Chaoyang District of Beijing,China 被引量:1
17
作者 Hong Min Jin Fengjun Brian D. Fath 《Chinese Journal of Population,Resources and Environment》 2010年第4期3-9,共7页
China is in the process of rapid urbanization,and wise land use is critical to the long-term sustainability of Chinese cities.Promotion of a compact city is typically believed to be helpful for sustainable land use ma... China is in the process of rapid urbanization,and wise land use is critical to the long-term sustainability of Chinese cities.Promotion of a compact city is typically believed to be helpful for sustainable land use management.However,given the fact that Chinese cities are characterized by high population densities,the applicability of a more compact solution to expand cities in China remains questionable;there is little evidence to support the many claims in its favor.In seeking to provide empirical data to explore the application of compact city theory in China,one of the key problems researchers face is the task of measuring the urban compactness,in order to objectively investigate the current characteristics of urban compactness.To meet this need,indices were developed for measuring the urban land use compactness,by which the spatial distribution characteristics of urban land use compactness were identified and applied to the Chaoyang District of Beijing.The conclusions can be made as follows:(1) comprehensive land use compactness in Chaoyang District has increased during the period of 2001-2007,especially the population density;(2) the spatial distribution of land use compactness has the characteristics of a ring structure,which shows a decreasing trend with its distance to the city center;(3) there is a strong positive correlation between urban land use compactness and location.The better the location is,the higher the land use compactness is. 展开更多
关键词 urban land use compactness measurement indices Chaoyang District
在线阅读 下载PDF
A Short Note on Compactness in Aligned Spaces and Higgs Spaces 被引量:1
18
作者 J. M. S. Sim6es-Pereira 《Journal of Mathematics and System Science》 2017年第6期151-153,共3页
We generalize to aligned spaces and to Higgs spaces the concept of compact topological spaces.
关键词 aligned spaces Higgs spaces compactness.
在线阅读 下载PDF
Measures of Countable Compactness and the Lindelf Property in L-Fuzzy Topological Spaces
19
作者 Hongyan LI Qinghua LI Ying ZHAO 《Journal of Mathematical Research with Applications》 CSCD 2015年第3期343-349,共7页
In this paper, the concept of countable compactness degree and the concept of Lindelof property degree are defined in L-fuzzy topological spaces by means of implication operator → Many properties of them are discussed.
关键词 L-fuzzy topology countable compactness Lindelof property implication operator fuzzy compactness degree
原文传递
Almost Fuzzy Compactness in L-fuzzy Topological Spaces
20
作者 Li Hong-yan Cui Wei Lei Feng-chun 《Communications in Mathematical Research》 CSCD 2015年第3期267-273,共7页
In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characte... In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characterizations of it arepresented. 展开更多
关键词 L-fuzzy topological space L-fuzzy almost compactness L-fuzzy compactness almost fuzzy compactness
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部