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New Constructions of Nullnorms on Bounded Lattices 认领
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作者 Jiajia Xie Wei Ji 《应用数学与应用物理(英文)》 2021年第1期1-10,共10页
We propose two more general methods to construct nullnorms on bounded lattices. By some illustrative examples, we demonstrate that the new method differ from the existing approaches.
关键词 Nullnorm Triangular Norm Triangular Subnorm Bounded Lattice
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文章速递Particle-in-cell simulation of ion-acoustic solitary waves in a bounded plasma 认领
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作者 位琳 刘博 +2 位作者 王芳平 张恒 段文山 《中国物理B:英文版》 SCIE EI CAS CSCD 2021年第3期364-370,共7页
We study some nonlinear waves in a viscous plasma which is confined in a finite cylinder.By averaging the physical quantities on the radial direction in some cases,we reduce this system to a simple one-dimensional mod... We study some nonlinear waves in a viscous plasma which is confined in a finite cylinder.By averaging the physical quantities on the radial direction in some cases,we reduce this system to a simple one-dimensional model.It seems that the effects of the bounded geometry(the radius of the cylinder in this case)can be included in the damping coefficient.We notice that the amplitudes of both Korteweg–de Vries(KdV)solitary waves and dark envelope solitary waves decrease exponentially as time increases from the particle-in-cell(PIC)simulation.The dependence of damping coefficient on the cylinder radius and the viscosity coefficient is also obtained numerically and analytically.Both are in good agreement.By using a definition,we give a condition whether a solitary wave exists in a bounded plasma.Moreover,some of potential applications in laboratory experiments are suggested. 展开更多
关键词 ion-acoustic solitary waves particle-in-cell simulation bounded plasmas
μ-Bergman空间到Zygmund型空间的加权复合算子 认领
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作者 赵艳辉 廖春艳 唐亚林 《数学杂志》 2021年第2期159-169,共11页
本文研究了单位圆盘D上的μ-Bergman空间到Zygmund型空间的加权复合算子的有界性和紧性问题.利用泛函分析多复变的方法,获得了单位圆盘上μ-Bergman空间到Zygmund型空间的加权复合算子为有界算子和紧算子的充要条件.
关键词 μ-Bergman空间 ZYGMUND型空间 加权复合算子 有界性 紧性
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Some Results on the Space of Bounded Second Variation Functions in the Sense of Shiba 认领
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作者 Liliana Pérez Ebner Pineda Luz Rodríguez 《理论数学进展(英文)》 2020年第5期245-258,共14页
In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space... In this paper, we study the structure of the space of functions of bounded second variation in the sense of Shiba;an integral representation theorem is also proved and necessary conditions are given for that the space be closed under composition of functions. Another significant result is the proof that this space of bounded second variation in the sense of Shiba is a Banach algebra, which is not immediate as it happens in other spaces of generalized bounded variation. 展开更多
关键词 Functional Analysis BOUNDED VARIATION Second BOUNDED VARIATION BANACH SPACE
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Evidences by Multiscale Analysis and 2D3/4 Models from the Magnetic Anomalies and Iron Mineralization (BIF) over the DJADOM-ETA Area, Southeastern Cameroon 认领
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作者 Justine Yandjimain Théophile Ndougsa-Mbarga +1 位作者 Arsène Meying Paul Claude Ngoumou 《地震研究(英文)》 2020年第1期19-32,共14页
The Magnetic method is one of the best geophysical techniques used to delineate subsurface structures. This study was conducted to investigate the basement faulting and ore mineralization into the overlying geological... The Magnetic method is one of the best geophysical techniques used to delineate subsurface structures. This study was conducted to investigate the basement faulting and ore mineralization into the overlying geological cover. The GEOSOFT v8.4 software was used to process the data. Upward continuation of the residual magnetic intensity map at various altitudes and the maxima of their horizontal gradient magnetic were used to highlight faults from shallow to deep, as well as, their dips and mineralization zones. The faults with the directions E-W, ESE-WNW and ENE-WSW are identified confirming the result of [1]. This study also reveals that, the layer is affected by faults propagating from the basement upwards into the cover. Our results added additional information to the knowledge of the geological structure and the mineral resources potential in the study area. Based on the 2D3/4 modeling, the Dja Fault (DF) is revealed and highlighted sub-area marked by a magnetite/or hematite dolerite, schist and sandstone blocks, which show strong magnetization. Specifically, in this area, models are made of BIF (bounded iron formation) and BIQ (bounded iron quartzite) as dominant minerals. 展开更多
关键词 AEROMAGNETIC Anomalies Multiscale Mineralization (BIF (Bounded IRON Formation) BIQ (Bounded IRON Quartzite)) HMG (Horizontal Gradient Magnetic) Faults
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Analysis of a Composition Operator’s Eigenvalue Equation on Unitary Spaces by the Krein-Rutman Theorem 认领
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作者 A. N. M. Rezaul Karim 《应用数学(英文)》 2020年第2期76-83,共8页
The Krein-Rutman theorem is vital in partial differential equations that are non-linear and provides evidence of the presence of several significant eigenvalues useful in topological degree calculations, stability ana... The Krein-Rutman theorem is vital in partial differential equations that are non-linear and provides evidence of the presence of several significant eigenvalues useful in topological degree calculations, stability analysis, and bifurcation theory. Schr?der’s equation which has been used extensively in studies of turbulence is an equation with a single independent variable suitable for encoding self-similarity. The concept of Hilbert spaces has been an inner product space frequently used due to its convenience in countless dimensional vector analysis. This paper is aimed at proving a number of solutions through the Krein-Rutman theorem in unitary spaces especially in Hilbert spaces. It has been certainly observed that the whole Krein-Rutman theorem system has a fairly stable scope, and has strong regular features, and many non-linear elliptic operators need the most ethical principles to satisfy the comparison policy. 展开更多
关键词 Krein-Rutman THEOREM UNITARY Space BOUNDED SOLUTIONS DIAGONALIZATION Schr?der Equation
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Global Bounded Solutions for the Keller-Segel Chemotaxis System with Singular Sensitivity 认领
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作者 Khalid Ahmed Abbakar Omer Khalil +3 位作者 Alhussein Mohamed Bechir Mahamat Abdoulaye Ali Abeer Alhadi 《应用数学(英文)》 2020年第10期985-990,共6页
In this paper, we consider the Neumann initial-boundary value problem for the Keller-Segel chemotaxis system with singular sensitivity <img src="Edit_4b941130-fc1e-4c9b-9626-4fd5a1f03836.bmp" alt="&q... In this paper, we consider the Neumann initial-boundary value problem for the Keller-Segel chemotaxis system with singular sensitivity <img src="Edit_4b941130-fc1e-4c9b-9626-4fd5a1f03836.bmp" alt="" />(0.1)<br /> <p> is considered in a bounded domain with smooth boundary, Ω &#8834;R<sup><i>n</i></sup> (<i>n</i> ≥ 1), where <i>d</i><sub>1</sub> > 0, <i>d</i><sub>2</sub> > 0 with parameter <i>χ</i> ∈ R. When <i>d</i><sub>1</sub> = <i>d</i><sub>2</sub> + <i>χ</i>, satisfying for all initial data 0 ≤ <i>n</i><sub>0</sub> ∈ <i>C</i><sup>0</sup><img src="Edit_4898c7a9-f047-4856-b9ad-8d42ecf262a2.bmp" alt="" /> and 0 < <i>v</i><sub>0</sub>∈ <i>W</i><sup>1,∞</sup> (Ω), we prove that the problem possesses a unique global classical solution which is uniformly bounded in Ω × (0, ∞). </p> 展开更多
关键词 Keller-Segel System CHEMOTAXIS Global Bounded Solution Singular Sensitivity
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The Existence of Solutions of a Space-Uniform Boltzmann Equation 认领
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作者 Zhihui Ye Rulv Li 《应用数学与应用物理(英文)》 2020年第2期294-300,共7页
Boltzmann equation is an equation which is related to the three variables of x, v, t. In this paper, we mainly study the space-uniform Boltzmann equation which unknown function F is not related to the position variabl... Boltzmann equation is an equation which is related to the three variables of x, v, t. In this paper, we mainly study the space-uniform Boltzmann equation which unknown function F is not related to the position variable x. We mainly use the contraction mapping theorem to find the existence of the solution, so our mainly work is to prove the self-mapping, i.e. to prove its uniformly bounded, and then to prove the contraction mapping. There we can get the range of ||B(θ)||L1(L∞), next we can figure out the range of M and T from the conditions what we know. Finally, from these conditions, we can find the existence of the solution. 展开更多
关键词 Space-Uniform BOLTZMANN Equations SELF-MAPPING Contractive Mapping UNIFORMLY BOUNDED The Existence of the Solution
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Bounded Evaluation:Querying Big Data with Bounded Resources 认领
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作者 Yang Cao Wen-Fei Fan Teng-Fei Yuan 《国际自动化与计算杂志:英文版》 EI CSCD 2020年第4期502-526,共25页
This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exist... This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exists a fraction DQ of D such that Q(D)=Q(DQ),and the cost of identifying DQ is independent of the size of D.It has been shown that with an auxiliary structure known as access schema,many queries in relational algebra(RA)are boundedly evaluable under the set semantics of RA.This paper extends the theory of bounded evaluation to RAaggr,i.e.,RA extended with aggregation,under the bag semantics.(1)We extend access schema to bag access schema,to help us identify DQ for RAaggr queries Q.(2)While it is undecidable to determine whether an RAaggr query is boundedly evaluable under a bag access schema,we identify special cases that are decidable and practical.(3)In addition,we develop an effective syntax for bounded RAaggr queries,i.e.,a core subclass of boundedly evaluable RAaggr queries without sacrificing their expressive power.(4)Based on the effective syntax,we provide efficient algorithms to check the bounded evaluability of RAaggr queries and to generate query plans for bounded RAaggr queries.(5)As proof of concept,we extend PostgreSQL to support bounded evaluation.We experimentally verify that the extended system improves performance by orders of magnitude. 展开更多
关键词 Bounded evaluation resource-bounded query processing effective syntax access schema BOUNDEDNESS
On the rate of convergence of two generalized Bernstein type operators 认领
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作者 LIAN Bo-yong CAI Qing-bo 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2020年第3期321-331,共11页
In this paper,we introduce the Bézier variant of two new families of generalized Bernstein type operators.We establish a direct approximation by means of the Ditzian-Totik modulus of smoothness and a global appro... In this paper,we introduce the Bézier variant of two new families of generalized Bernstein type operators.We establish a direct approximation by means of the Ditzian-Totik modulus of smoothness and a global approximation theorem in terms of second order modulus of continuity.By means of construction of suitable functions and the method of Bojanic and Cheng,we give the rate of convergence for absolutely continuous functions having a derivative equivalent to a bounded variation function. 展开更多
关键词 Bernstein operators modulus of smoothness rate of convergence bounded variation
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Tracking Control of Uncertain Nonlinear Systems With Unknown Constant Input Delay 认领
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作者 Ashish Kumar Jain Shubhendu Bhasin 《自动化学报:英文版》 EI CSCD 2020年第2期420-425,共6页
A robust delay compensator has been developed for a class of uncertain nonlinear systems with an unknown constant input delay.The control law consists of feedback terms based on the integral of past control values and... A robust delay compensator has been developed for a class of uncertain nonlinear systems with an unknown constant input delay.The control law consists of feedback terms based on the integral of past control values and a novel filtered tracking error,capable of compensating for input delays.Suitable Lyapunov-Krasovskii functionals are used to prove global uniformly ultimately bounded(GUUB)tracking,provided certain sufficient gain conditions,dependent on the bound of the delay,are satisfied.Simulation results illustrate the performance and robustness of the controller for different values of input delay. 展开更多
关键词 Global UNIFORMLY ultimately BOUNDED stability LYAPUNOV-KRASOVSKII FUNCTIONALS nonlinear systems tracking control UNKNOWN input delay
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Fibrations and stability for compact group actions on manifolds with local bounded Ricci covering geometry 认领
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作者 Hongzhi HUANG 《中国数学前沿:英文版》 SCIE CSCD 2020年第1期69-89,共21页
In the study of the collapsed manifolds with bounded sectional curvature,the following two results provide basic tools:a(singular)fibration theorem by K.Fukaya[J.Differential Gcom.,1987.25(1):139156]and J.Cheeger,K.Fu... In the study of the collapsed manifolds with bounded sectional curvature,the following two results provide basic tools:a(singular)fibration theorem by K.Fukaya[J.Differential Gcom.,1987.25(1):139156]and J.Cheeger,K.Fukaya,and M.Gromov[J.Airier.Math.Soc.,1992.5(2):327372],and the stability for isometric compact Lie group actions on manifolds by R.S.Palais[Bull.Amer.Math.Soc.,1961,67(4):362364]and K.Grove and H.Karcher[Math.Z..1973,132:1120].The main results in this paper(partially)generalize the two results to manifolds with local bounded Ricci covering geometry. 展开更多
关键词 FIBRATIONS STABILITY for group actions nilpotent structures RICCI curvature BOUNDED RICCI COVERING GEOMETRY
多圆柱上加权Bergman空间到Bloch型空间的加权Cesàro算子 认领
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作者 赵艳辉 廖春艳 +1 位作者 邓春红 吴修云 《浙江大学学报:理学版》 CAS CSCD 北大核心 2020年第2期151-154,共4页
利用泛函分析以及多复变方法,研究了多圆柱上加权Bergman空间到Bloch型空间的加权Cesàro算子问题,得到了多圆柱上加权Bergman空间到Bloch型空间的加权Cesàro算子为有界算子和紧算子的充要条件,并给出了单位圆盘上加权Bergman... 利用泛函分析以及多复变方法,研究了多圆柱上加权Bergman空间到Bloch型空间的加权Cesàro算子问题,得到了多圆柱上加权Bergman空间到Bloch型空间的加权Cesàro算子为有界算子和紧算子的充要条件,并给出了单位圆盘上加权Bergman空间到Bloch型空间的加权Cesàro算子为有界算子和紧算子的充要条件。 展开更多
关键词 加权BERGMAN空间 BLOCH型空间 加权CESÀRO算子 有界性 紧性
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单位球上加权Bergman空间到Zμ型空间的加权Cesàro算子 认领
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作者 赵艳辉 吴修云 廖春艳 《数学物理学报:A辑》 CSCD 北大核心 2020年第3期569-578,共10页
该文利用泛函分析以及多复变的方法,研究了单位球B上加权Bergman空间到Zμ型空间的加权Cesaro算子的有界性和紧性问题.获得了单位球上加权Bergman空间到Zμ型空间的加权Cesaro算子为有界算子和紧算子的充要条件.
关键词 加权BERGMAN空间 Zμ型空间 加权CESÀRO算子 有界性 紧性
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Bounded Tiles in Qp are Compact Open Sets 认领
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作者 Ai Hua FAN Shi Lei FAN 《数学学报:英文版》 SCIE CSCD 2020年第2期189-195,共7页
Any bounded tile of the field Qp of p-adic numbers is a compact open set up to a set of zero Haar measure.In this note,we present two simple and direct proofs of this fact.
关键词 P-ADIC field TILE BOUNDED COMPACT OPEN
Support points for families of univalent mappings on bounded symmetric domains 认领 被引量:1
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作者 Hidetaka Hamada Gabriela Kohr 《中国科学:数学英文版》 SCIE CSCD 2020年第12期2379-2398,共20页
In this paper,we study some extremal problems for the family Sg^0(BX)of normalized univalent mappings with g-parametric representation on the unit ball BX of an n-dimensional JB*-triple X with r≥2,where r is the rank... In this paper,we study some extremal problems for the family Sg^0(BX)of normalized univalent mappings with g-parametric representation on the unit ball BX of an n-dimensional JB*-triple X with r≥2,where r is the rank of X and g is a convex(univalent)function on the unit disc U,which satisfies some natural assumptions.We obtain sharp coefficient bounds for the family Sg^0(BX),and examples of bounded support points for various subsets of Sg^0(BX).Our results are generalizations to bounded symmetric domains of known recent results related to support points for families of univalent mappings on the Euclidean unit ball B^n and the unit polydisc U^n in C^n.Certain questions will be also mentioned.Finally,we point out sharp coefficient bounds and bounded support points for the family Sg^0(B^n)and for special compact subsets of Sg^0(B^n),in the case n≥2. 展开更多
关键词 bounded symmetric domain Carathéodory family g-Loewner chain parametric representation starlike mapping support point
Continuity of Hardy-Littlewood Maximal Function 认领
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作者 Di WU Dun-yan YAN 《应用数学学报:英文版》 SCIE CSCD 2020年第4期982-990,共9页
In the paper,we characterize a necessary and sufficient condition which ensures the continuities of the non-centered Hardy-Lit tiewood maximal function Mf and the centered Hardy-Lit tiewood maximal function Mcf on R^n... In the paper,we characterize a necessary and sufficient condition which ensures the continuities of the non-centered Hardy-Lit tiewood maximal function Mf and the centered Hardy-Lit tiewood maximal function Mcf on R^n.As two applications,we can easily deduce that Mcf and Mf are continuous if f is continuous,and Mf is continuous if f is of local bounded variation on R. 展开更多
关键词 Hardy-Littlewood maximal function bounded variation CONTINUITY
Theories behind a nursing intern’s error in terms of clinical decision-making 认领
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作者 Meng Wu 《护理前沿(英文)》 CAS 2020年第3期209-215,共7页
Clinical decision-making and judgment is an essential skill that should be acquired by nursing interns.However,many studies reveal that a large proportion of nursing interns have difficulty in meeting the basic expect... Clinical decision-making and judgment is an essential skill that should be acquired by nursing interns.However,many studies reveal that a large proportion of nursing interns have difficulty in meeting the basic expectation of clinical decision-making.This article begins with a brief review of some theories related to clinical decision-making.Then it takes a case,for example,to show how the wrong decision is made.Furthermore,it makes a general analysis on the case drawing on the concept of bounded rationality,dual-process model,and skills acquisition theory.This article ends with some reflections from the case,to improve the consciousness and skills in decision-making for nursing interns. 展开更多
关键词 nursing intern DECISION-MAKING REVIEW bounded rationality dual process theory skill acquisition theory
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Multi-UAV cooperative target tracking with bounded noise for connectivity preservation 认领
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作者 Rui ZHOU Yu FENG +2 位作者 Bin DI Jiang ZHAO Yan HU 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2020年第10期1494-1503,共10页
We investigate cooperative target tracking of multiple unmanned aerial vehicles(UAVs)with a limited communication range.This is an integration of UAV motion control,target state estimation,and network topology control... We investigate cooperative target tracking of multiple unmanned aerial vehicles(UAVs)with a limited communication range.This is an integration of UAV motion control,target state estimation,and network topology control.We first present the communication topology and basic notations for network connectivity,and introduce the distributed Kalman consensus filter.Then,convergence and boundedness of the estimation errors using the filter are analyzed,and potential functions are proposed for communication link maintenance and collision avoidance.By taking stable target tracking into account,a distributed potential function based UAV motion controller is discussed.Since only the estimation of the target state rather than the state itself is available for UAV motion control and UAV motion can also affect the accuracy of state estimation,it is clear that the UAV motion control and target state estimation are coupled.Finally,the stability and convergence properties of the coupled system under bounded noise are analyzed in detail and demonstrated by simulations. 展开更多
关键词 Multi-UAV cooperative target tracking Network connectivity Kalman consensus filter Bounded noise Connectivity preservation
Boundedness and Almost Periodicity of Solutions for a Class of Semilinear Parabolic Equations with Boundary Degeneracy 认领
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作者 Yi XIE Peidong LEI 《数学年刊:B辑英文版》 SCIE CSCD 2020年第2期303-324,共22页
In this paper the authors investigate the boundedness and almost periodicity of solutions of semilinear parabolic equations with boundary degeneracy. The equations may be weakly degenerate or strongly degenerate on th... In this paper the authors investigate the boundedness and almost periodicity of solutions of semilinear parabolic equations with boundary degeneracy. The equations may be weakly degenerate or strongly degenerate on the lateral boundary. The authors prove the existence, uniqueness and global exponential stability of bounded entire solutions, and also establish the existence theorem of almost periodic solutions if the data are almost periodic. 展开更多
关键词 ALMOST periodic SOLUTION BOUNDED entire SOLUTION BOUNDARY DEGENERACY
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