期刊文献+
共找到32篇文章
< 1 2 >
每页显示 20 50 100
Some Results of Upper and Lower <i>M</i>-Asymmetric Irresolute Multifunctions in Bitopological Spaces 被引量:1
1
作者 Levy K. Matindih Edwin Moyo +1 位作者 Davy K. Manyika Timothy Sinyangwe 《Advances in Pure Mathematics》 2021年第6期611-627,共17页
In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces wi... In this paper, we aim to introduce and study some basic properties of upper and lower <em>M</em>-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces with certain minimal structures as a generalization of irresolute functions deal to Crossley and Hildebrand <a href="#ref1">[1]</a> and upper and lower irresolute Multifunctions deal to Popa <a href="#ref2">[2]</a>. 展开更多
关键词 TiTj-Semiopen Sets M-Space M-Asymmetric Semiopen and Semiclosed Sets upper (lower) Irresolute Multifunctions and upper (lower) M-Asymmetric Irresolute Multifunctions
下载PDF
The role of fluids in the lower crust and upper mantle:A tribute to Jacques Touret
2
作者 Daniel Harlov 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第5期621-625,共5页
This special issue of Geoscience Frontiers is a tribute volume honoring the life and career of Jacques Touret. A set of research papers has been assembled, which broadly reflect his research interests over his 50 plus... This special issue of Geoscience Frontiers is a tribute volume honoring the life and career of Jacques Touret. A set of research papers has been assembled, which broadly reflect his research interests over his 50 plus year career. These papers Focus on the role that fluids play during the Formation and evolution of the Earth's crust. Below I provide a brief summary of the life of Jacques Touret, along with a select bibliography of his more important papers. This is then followed by a brief introduction to the papers assembled for this special issue. 展开更多
关键词 The role of fluids in the lower crust and upper mantle
下载PDF
SOME NECESSARY AND SUFFICIENT CONDITIONS FOR EXISTENCE OF POSITIVE SOLUTIONS FOR THIRD ORDER SINGULAR SUBLINEAR MULTI-POINT BOUNDARY VALUE PROBLEMS 被引量:5
3
作者 韦忠礼 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1795-1810,共16页
We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0... We mainly study the existence of positive solutions for the following third order singular multi-point boundary value problem{x^(3)(t) + f(t, x(t), x′(t)) = 0, 0 〈 t 〈 1,x(0)-∑i=1^m1 αi x(ξi) = 0, x′(0)-∑i=1^m2 βi x′(ηi) = 0, x′(1)=0,where 0 ≤ ai≤∑i=1^m1 αi 〈 1, i = 1, 2, ···, m1, 0 〈 ξ1〈 ξ2〈 ··· 〈 ξm1〈 1, 0 ≤βj≤∑i^m2=1βi〈1,J=1,2, ···, m2, 0 〈 η1〈 η2〈 ··· 〈 ηm2〈 1. And we obtain some necessa βi 〈=11, j = 1,ry and sufficient conditions for the existence of C^1[0, 1] and C^2[0, 1] positive solutions by constructing lower and upper solutions and by using the comparison theorem. Our nonlinearity f(t, x, y)may be singular at x, y, t = 0 and/or t = 1. 展开更多
关键词 boundary value problems positive solutions lower and upper solutions comparison theorem
下载PDF
Uncertainty and Reduction in Intuitionistic Fuzzy Covering Based Rough Sets
4
作者 FENG Tao MI Ju-Sheng 《浙江海洋学院学报(自然科学版)》 CAS 2010年第5期481-487,共7页
This paper proposes a novel pair of induced IF covering approximation operators in an IF covering approximation space,and discusses some basic properties about definable IFSs.A measure is defined to describe the uncer... This paper proposes a novel pair of induced IF covering approximation operators in an IF covering approximation space,and discusses some basic properties about definable IFSs.A measure is defined to describe the uncertainty of IFSs in IF covering approximation spaces.Finally,we study the properties of reductions of an IF covering respectively based on induced IF covering approximation operators and IF covering approximation operators. 展开更多
关键词 IF covering induced IF lower and upper approximation operators REDUCTION UNCERTAINTY
下载PDF
Minimum Cost of Capacity Expansion for Time-Limited Transportation Problem On-Demand
5
作者 Hui Ding Zhimin Zou 《Journal of Computer and Communications》 2022年第7期53-71,共19页
The minimum cost of capacity expansion for time-limited transportation problem on-demand (MCCETLTPD) is to find such a practicable capacity expansion transportation scheme satisfying the time-limited T along with all ... The minimum cost of capacity expansion for time-limited transportation problem on-demand (MCCETLTPD) is to find such a practicable capacity expansion transportation scheme satisfying the time-limited T along with all origins’ supply and all destinations’ demands as well as the expanding cost is minimum. Actually, MCCETLTPD is a balance transportation problem and a variant problem of minimum cost maximum flow problem. In this paper, by creating a mathematical model and constructing a network with lower and upper arc capacities, MCCETLTPD is transformed into searching feasible flow in the constructed network, and consequently, an algorithm MCCETLTPD-A is developed as MCCETLTPD’s solution method basing minimum cost maximum flow algorithm. Computational study validates that the MCCETLTPD-A algorithm is an efficient approach to solving the MCCETLTPD. 展开更多
关键词 Capacity Expansion Minimum Cost Maximum Flow Transportation Problem Network with lower and upper Arc Capacities
下载PDF
Positive Solutions to Singular Boundary Value Problems with Sign Changing Nonlinearities on the Half-Line via Upper and Lower Solutions 被引量:5
6
作者 Bao Qiang YAN Donal O'REGAN Ravi P. AGARWAL 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第8期1447-1456,共10页
This paper presents a lower and upper solution technique for singular second order boundary value problems on the half line.
关键词 boundary value problems lower and upper solutions Schauder's fixed point theorem
原文传递
Existence Results for Systems of Nonlinear Caputo Fractional Differential Equations
7
作者 Faten Toumi 《Applied Mathematics》 2023年第3期182-195,共14页
We aim, in this work, to demonstrate the existence of minimal and maximal coupled quasi-solutions for nonlinear Caputo fractional differential systems with order q ∈ (1,2). Our approach is based on mixed monotone ite... We aim, in this work, to demonstrate the existence of minimal and maximal coupled quasi-solutions for nonlinear Caputo fractional differential systems with order q ∈ (1,2). Our approach is based on mixed monotone iterative techniques developed under the concept of lower and upper quasi-solutions. Our results extend those obtained for ordinary differential equations and fractional ones. 展开更多
关键词 Mixed Quasi-Monotone Property Coupled lower and upper Solutions Mon-otone Method Nonlinear Fractional Differential System
下载PDF
Periodic boundary value problem for the first order functional differential equations with impulses 被引量:5
8
作者 LIANG Rui-xi SHEN Jian-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第1期27-35,共9页
This paper is concerned with the existence and approximation of solutions for a class of first order impulsive functional differential equations with periodic boundary value conditions. A new comparison result is pres... This paper is concerned with the existence and approximation of solutions for a class of first order impulsive functional differential equations with periodic boundary value conditions. A new comparison result is presented and the previous results are extended. 展开更多
关键词 functional differential equation periodic boundary value problem lower and upper solution monotone iterative method
下载PDF
Frequency-Agile WLAN Notch UWB Antenna for URLLC Applications 被引量:4
9
作者 Amir Haider MuhibUr Rahman +3 位作者 Hamza Ahmad Mahdi NaghshvarianJahromi Muhammad Tabish Niaz Hyung Seok Kim 《Computers, Materials & Continua》 SCIE EI 2021年第5期2243-2254,共12页
This paper introduces a compact dual notched UWB antenna with an independently controllable WLAN notched band integrated with fixed WiMAX band-notch.The proposed antenna utilizes a slot resonator placed in the main ra... This paper introduces a compact dual notched UWB antenna with an independently controllable WLAN notched band integrated with fixed WiMAX band-notch.The proposed antenna utilizes a slot resonator placed in the main radiator of the antenna for fixed WiMAX band notch,while an inverted L-shaped resonator in the partial ground plane for achieving frequency agility within WLAN notched band.The inverted L-shaped resonator is also loaded with fixed and variable capacitors to control and adjust the WLAN notch.The WLAN notched band can be controlled independently with a wide range of tunability without disturbing the WiMAX bandnotch performance.Step by step design approach of the proposed antenna is discussed and the corresponding mathematical analysis of the proposed resonators are provided in both cases.Simulation of the proposed antenna is performed utilizing commercially available 3D-EM simulator,Ansoft High Frequency Structure Simulator(HFSS).The proposed antenna has high selectivity with experimental validation in terms of reflection coefficient,radiation characteristics,antenna gain,and percentage radiation efficiency.The corresponding measured frequency response of the input port corresponds quite well with the calculations and simulations in both cases.The proposed antenna is advantageous and can adjust according to the device requirements and be one of the attractive candidates for overlay cognitive radio UWB applications and URLLC service in 5G tactile internet.The proposed multifunctional antenna can also be used for wireless vital signs monitoring,sensing applications,and microwave imaging techniques. 展开更多
关键词 WiMAX UWB lower and upper WLAN single/dual notch behavior independent controlling notched behavior tunable band-notch behavior overlay cognitive radio applications frequency-agile WLAN notched antennas 5G URLLC tactile internet
下载PDF
ON MONOTONE ITERATIVE METHOD FOR INITIAL VALUE PROBLEMS OF NONLINEAR SECOND-ORDER INTEGRO-DIFFERENTIAL EQUATIONS IN BANACH SPACES 被引量:3
10
作者 陈芳启 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第5期509-518,共10页
Using the monotone iterative method and Monch Fixed point theorem, the existence of solutions and coupled minimal and maximal quasisolutions of initial value problems for mixed monotone second-order integro-differenti... Using the monotone iterative method and Monch Fixed point theorem, the existence of solutions and coupled minimal and maximal quasisolutions of initial value problems for mixed monotone second-order integro-differential equations in Banach spaces are studied. Some existence theorems of solutions and coupled minimal and maximal quasisolutions are obtained. 展开更多
关键词 integro-differential equations Kuratowski measure of noncompactness coupled lower and upper quasisolutions monotone iterative method
下载PDF
A class of singular perturbation solutions to semilinear equations of fourth order
11
作者 莫嘉琪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第11期1455-1460,共6页
A class of singularly perturbed boundary value problems for semilinear equations of fourth order with two parameters are considered. Under suitable conditions, using the method of lower and upper solutions, the existe... A class of singularly perturbed boundary value problems for semilinear equations of fourth order with two parameters are considered. Under suitable conditions, using the method of lower and upper solutions, the existence and the asymptotic behavior of the solution to the boundary value problem are studied, In the present paper, the solution to the original singularly perturbed problem with two parameters has only one boundary layer. 展开更多
关键词 NONLINEAR two parameters singular perturbation lower and upper solutions
下载PDF
Valuation of American Strangles Through an Optimized Lower–Upper Bound Approach
12
作者 Jing-Tang Ma Wen-Yuan Li Zhen-Yu Cui 《Journal of the Operations Research Society of China》 EI CSCD 2018年第1期25-47,共23页
In this paper,we construct tight lower and upper bounds for the price of an American strangle,which is a special type of strangle consisting of long positions in an American put and an American call,where the early ex... In this paper,we construct tight lower and upper bounds for the price of an American strangle,which is a special type of strangle consisting of long positions in an American put and an American call,where the early exercise of one side of the position will knock out the remaining side.This contract was studied in Chiarella and Ziogas(J Econ Dyn Control 29:31–62,2005)with the corresponding nonlinear integral equations derived,which are hard to be solved efficiently through numerical methods.We extend the approach in the paper of Broadie and Detemple(Rev Finance Stud 9:1211–1250,1996)from the case of American call options to the case of American strangles.We establish theoretical properties of the lower and upper bounds,and propose a sequential optimization algorithm in approximating the early exercise boundary of the American strangle. The theoretical bounds obtained can beeasily evaluated, and numerical examples confirm the accuracy of the approximationscompared to the literature. 展开更多
关键词 Option pricing American strangle lower and upper bounds Early exercise boundaries OPTIMIZATION
原文传递
Existence of Solutions to the Higher Order Nonlinear Differential Equations
13
作者 TANG Lin-shan JIANG Cheng-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期1-10,共10页
This paper is concerned with the following n-th ordinary differential equation:{u~(n)(t)=f(t,u(t),u~(1)(t),···,u~(n-1) (t)),for t∈(0,1),u~(i) (0)=0,0 ≤i≤n3,au~(n-2)(0)du~(n-1)(0)=0,cu~(n-2)(1)... This paper is concerned with the following n-th ordinary differential equation:{u~(n)(t)=f(t,u(t),u~(1)(t),···,u~(n-1) (t)),for t∈(0,1),u~(i) (0)=0,0 ≤i≤n3,au~(n-2)(0)du~(n-1)(0)=0,cu~(n-2)(1)+du~(n-1)(1)=0,where a,c ∈ R,,≥,such that a~2 + b~2 >0 and c~2+d~2>0,n ≥ 2,f:[0,1] × R → R is a continuous function.Assume that f satisfies one-sided Nagumo condition,the existence theorems of solutions of the boundary value problem for the n-th-order nonlinear differential equations above are established by using Leray-Schauder degree theory,lower and upper solutions,a priori estimate technique. 展开更多
关键词 n-th order boundary value problems one-sided Nagumo condition lower and upper solutions a priori estimates Leray-Schauder degree
下载PDF
Coupled Extremal Quasi-solutions to Nonlinear Impulsive Fredholm Integral Equations in Banach Spaces
14
作者 戚仕硕 《Northeastern Mathematical Journal》 CSCD 2000年第3期329-338,共10页
By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in ... By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in Banach sp aces and proves the existence theorem on their coupled extremal quasisolutions . Finally, an infinite system of nonlinear impulsive integral equations is provi ded to demonstrate the obtained results. 展开更多
关键词 coupled lower and upper quasi-solutions iterative techn ique impulsive Fredholm integral equation Banach space normal cone
下载PDF
Existence Theorems for a Fifth-Order Boundary Value Problem
15
作者 Amir Elhaffaf Mostepha Naceri 《Journal of Mathematics and System Science》 2014年第1期1-5,共5页
Abstract: In this paper, we study the existence of a solution for fifth-order boundary value problem{u(5)(t)+f(t,u(t),u"(t)=0,0〈t〈1)/u(0)=u'(0)=u'(1)=u"(1)=u(4)(0)=0 Where f ∈ C([0,1] &... Abstract: In this paper, we study the existence of a solution for fifth-order boundary value problem{u(5)(t)+f(t,u(t),u"(t)=0,0〈t〈1)/u(0)=u'(0)=u'(1)=u"(1)=u(4)(0)=0 Where f ∈ C([0,1] × R2, R). By placing certain restrictions on the nonlinear term f, we prove the existence of at least one solution to the boundary value problem with the use of the lower and upper solution method and Schauder fixed-point theorem. The construction of lower or upper solution is also present.ed. Boundary value problems of very similar type are also considered. 展开更多
关键词 Fifth-order differential equations boundary value problems lower and upper solution method Schauder fixed-pointtheorem.
下载PDF
Alleviating limit cycling in training GANs with an optimization technique 被引量:1
16
作者 Keke Li Liping Tang Xinmin Yang 《Science China Mathematics》 SCIE CSCD 2024年第6期1287-1316,共30页
In this paper,we undertake further investigation to alleviate the issue of limit cycling behavior in training generative adversarial networks(GANs)through the proposed predictive centripetal acceleration algorithm(PCA... In this paper,we undertake further investigation to alleviate the issue of limit cycling behavior in training generative adversarial networks(GANs)through the proposed predictive centripetal acceleration algorithm(PCAA).Specifically,we first derive the upper and lower complexity bounds of PCAA for a general bilinear game,with the last-iterate convergence rate notably improving upon previous results.Then,we combine PCAA with the adaptive moment estimation algorithm(Adam)to propose PCAA-Adam,for practical training of GANs to enhance their generalization capability.Finally,we validate the effectiveness of the proposed algorithm through experiments conducted on bilinear games,multivariate Gaussian distributions,and the CelebA dataset,respectively. 展开更多
关键词 GANs general bilinear game predictive centripetal acceleration algorithm lower and upper complexity bounds PCAA-Adam
原文传递
Existence and Uniqueness of Fixed Point in Partially Ordered Sets and Applications to Ordinary Differential Equations 被引量:15
17
作者 Juan J.NIETO RosanaRODRGUEZ-LPEZ 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第12期2205-2212,共8页
We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing... We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution. 展开更多
关键词 fixed point partially ordered set first-order differential equation lower and upper solutions
原文传递
Limiting Behaviors for Longest Consecutive Switches in anⅡD Bernoulli Sequence
18
作者 Chen Xu HAO Ting MA 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2023年第6期1138-1146,共9页
In this paper we mainly discuss lower and upper bounds for the length of longest consecutive switches inⅡD Bernoulli sequences.This work is an extension of results for longest consecutive switches in unbiased coin-to... In this paper we mainly discuss lower and upper bounds for the length of longest consecutive switches inⅡD Bernoulli sequences.This work is an extension of results for longest consecutive switches in unbiased coin-tossing,and might be applied to reliability theory,biology,quality control,pattern recognition,finance,etc. 展开更多
关键词 Longest consecutive switches lower and upper bounds Borel-Cantelli lemma
原文传递
PBVP of Integrodifferential Equations with Carathéodory Functions 被引量:7
19
作者 Zhuang Wan Chen Yubo, Department of Mathematics, Shandong Normal University, Jinan 250014, China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1998年第4期463-472,共10页
We study the periodic boundary value problems for nonlinear integro-differential equa- tions of Volterra type with Carathéodory functions. For two situations relative to lower and upper solutions α and β:αβ ... We study the periodic boundary value problems for nonlinear integro-differential equa- tions of Volterra type with Carathéodory functions. For two situations relative to lower and upper solutions α and β:αβ or β α, the existence of solutions and the monotone iterative method for establishing extreme solutions are considered. 展开更多
关键词 Integrodifferential equations Periodic boundary value problems Carathéodory conditions lower and upper solutions Sobolev spaces Topological degree
原文传递
Positive Solution of Singular Boundary Value Problems on a Half-Line 被引量:9
20
作者 Zhong-li Wei Shao-zhu Chen 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第4期553-564,共12页
This paper investigates existence of positive solutions of singular sub-linear boundary value problems on a half-line. Necessary and sufficient conditions for the existence of positive continuous solutions or smooth s... This paper investigates existence of positive solutions of singular sub-linear boundary value problems on a half-line. Necessary and sufficient conditions for the existence of positive continuous solutions or smooth solutions on [0, ∞] are given by constructing new lower and upper solutions. 展开更多
关键词 Singular boundary value problem on a half-line positive solution lower and upper solutions
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部