期刊文献+
共找到1,122篇文章
< 1 2 57 >
每页显示 20 50 100
Mixed Monotone Iterative Technique and Boundary Value Problem for a Class of Impulsive Integro-Differential Equations
1
作者 支妍妍 陈海波 吕晨辉 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期46-53,共8页
In this paper,the existence and uniqueness of iterative solutions to the boundary value problems for a class of first order impulsive integro-differential equations were studied. Under a new concept of upper and lower... In this paper,the existence and uniqueness of iterative solutions to the boundary value problems for a class of first order impulsive integro-differential equations were studied. Under a new concept of upper and lower solutions, a new monotone iterative technique on the boundary value problem of integro-differential equations was proposed. The existence and uniqueness of iterative solutions and the error estimation in certain interval were obtained.An example was also given to illustrate the results. 展开更多
关键词 impulsive integro-differential equations L-quasi-upper and lower solutions mixed monotone iterative technique boundary value problem
下载PDF
Mixed Monotone Iterative Technique for Singular Hadamard Fractional Integro-Differential Equations in Banach Spaces
2
作者 Xinwei Su Shuqin Zhang Yu Hui 《Journal of Applied Mathematics and Physics》 2022年第12期3843-3863,共21页
This paper deals with fractional integro-differential equations involving Hadamard fractional derivatives and nonlinear boundary conditions in an ordered Banach space. The nonlinearity is allowed to be singular with r... This paper deals with fractional integro-differential equations involving Hadamard fractional derivatives and nonlinear boundary conditions in an ordered Banach space. The nonlinearity is allowed to be singular with respect to time variable. Under some monotonicity conditions and noncompactness measure conditions, we use the method of coupled lower and upper L-quasisolutions associated with the mixed monotone iterative technique to investigate the existence of extremal L-quasisolutions. A unique solution between coupled lower and upper L-quasisolutions is also obtained. An example is given to illustrate our theoretical results. The results got in this paper are new and enrich the existing related work. 展开更多
关键词 Hadamard Fractional Derivative Nonlinear Boundary Condition monotone iterative technique Noncompactness Measure
下载PDF
Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
3
作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem Sign-Changing Green’s Function Fixed Point Index iterative technique monotone Positive Solution EXISTENCE
下载PDF
MONOTONE ITERATIVE TECHNIQUE FOR NONLINEAR NEUTRAL DELAY DIFFERENTIAL EQUATIONS
4
作者 姜子文 庄万 《Acta Mathematica Scientia》 SCIE CSCD 1998年第3期285-292,共8页
The objective of this paper is to develop monotone techniques for obtaining extremal solutions of initial value problem for nonlinear neutral delay differential equations.
关键词 monotone iterative technique neutral delay differential equation initial value problem extremal solutions
全文增补中
Monotone Iterative Method for Nonlinear Discontinuous Differential Equations 被引量:6
5
作者 Sun Lelin Lei Jingan 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第1期1-4,共4页
A monotone iterative method for some discontinuous variational boundary problems is given, the convergence of iterative solutions is proved by the theory of partially ordered sets. It can be regarded as a generalizati... A monotone iterative method for some discontinuous variational boundary problems is given, the convergence of iterative solutions is proved by the theory of partially ordered sets. It can be regarded as a generalization of the classical monotone iteration theory for continuous problems. 展开更多
关键词 nonlinear differential equations approximate solution monotone iterative
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
6
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
SOME NEW ITERATIVE ALGORITHMS FOR MONOTONE MIXED VARIATIONAL INEQUALITIES 被引量:4
7
作者 Zhang XianDept. of Basic Courses,Jimei Univ.,Xiamen 361021. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期80-84,共5页
In this paper,some new iterative algorithms for monotone mixed variational inequalities and the convergence in real Hilbert spaces are studied.
关键词 mixed variational inequality iterative algorithm monotone operator. Supported by Natural Science Foundation of Education Council of Fujian Province of China.
下载PDF
Monotone Iterative Methodfor Nonlinear Discontinuous ParabolicDifferential Equations 被引量:2
8
作者 Zou Qingsong Tian Yan Let Jingan(College of Mathematical Sciences, Wuhan University, Wuhan 430072, China) 《Wuhan University Journal of Natural Sciences》 CAS 1998年第4期389-393,共5页
In this paper, the existence of solutions for discontinuous nonlinear parabolic differential IBVP is proved by using a more generalized monotone iterative method. Moreover, the convergence of this method is discussed.
关键词 discontinuous nonlinear equation monotone iterative method parabolic IBVP
下载PDF
Iterative technique for circular thin plates on Gibson elastic foundation using modified Vlasov model 被引量:1
9
作者 Feng Yue Ziyan Wu +1 位作者 Haifeng Yang Mengying Li 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第5期312-319,I0005,共9页
In this paper, to investigate the influence of soil inhomogeneity on the bending of circular thinplates on elastic foundations, the static problem of circular thin plates on Gibson elasticfoundation is solved using an... In this paper, to investigate the influence of soil inhomogeneity on the bending of circular thinplates on elastic foundations, the static problem of circular thin plates on Gibson elasticfoundation is solved using an iterative method based on the modified Vlasov model. On the basisof the principle of minimum potential energy, the governing differential equations and boundaryconditions for circular thin plates on modified Vlasov foundation considering the characteristics ofGibson soil are derived. The equations for the attenuation parameter in bending problem are alsoobtained, and the issue of unknown parameters being difficult to determine is solved using theiterative method. Numerical examples are analyzed and the results are in good agreement withthose form other literatures. It proves that the method is practical and accurate. Theinhomogeneity of modified Vlasov foundations has some influence on the deformation andinternal force behavior of circular thin plates. The effects of various parameters on the bending ofcircular plates and characteristic parameters of the foundation are discussed. The modified modelfurther enriches and develops the elastic foundations. Relevant conclusions that are meaningful toengineering practice are drawn. 展开更多
关键词 CIRCULAR thin plate GIBSON soil MODIFIED VLASOV model Bendings iterative technique
下载PDF
AN ITERATIVE ALGORITHM FOR MAXIMAL MONOTONE MULTIVALUED OPERATOR EQUATIONS 被引量:1
10
作者 肖进胜 孙乐林 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期152-158,共7页
A proximal iterative algorithm for the mulitivalue operator equation 0 ∈ T(x) is presented, where T is a maximal monotone operator. It is an improvement of the proximal point algorithm as well know. The convergence o... A proximal iterative algorithm for the mulitivalue operator equation 0 ∈ T(x) is presented, where T is a maximal monotone operator. It is an improvement of the proximal point algorithm as well know. The convergence of the algorithm is discussed and all example is given. 展开更多
关键词 iterative algorithm maximal monotone operator multivalued operator
下载PDF
The Iterative Solution for a Class of Monotone Operator Equations 被引量:1
11
作者 Xiao Jin-sheng Lei Jin-gan 《Wuhan University Journal of Natural Sciences》 CAS 1999年第2期24-26,共3页
The iterative solution for a class of multivalued monotone operator equations just like A(u)∈-B(u) is discussed, where A is a positive definite linear single valued operator, B is a bounded and m... The iterative solution for a class of multivalued monotone operator equations just like A(u)∈-B(u) is discussed, where A is a positive definite linear single valued operator, B is a bounded and monotone multivalued operator. The existence and convergence of approximate solutions are proved. The method of numerical realization is demonstrated in some examples. 展开更多
关键词 multivalued operator monotone operator iterative solution
下载PDF
GLOBAL CONVERGENCE RESULTS OF A THREE TERM MEMORY GRADIENT METHOD WITH A NON-MONOTONE LINE SEARCH TECHNIQUE 被引量:12
12
作者 孙清滢 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期170-178,共9页
In this paper, a new class of three term memory gradient method with non-monotone line search technique for unconstrained optimization is presented. Global convergence properties of the new methods are discussed. Comb... In this paper, a new class of three term memory gradient method with non-monotone line search technique for unconstrained optimization is presented. Global convergence properties of the new methods are discussed. Combining the quasi-Newton method with the new method, the former is modified to have global convergence property. Numerical results show that the new algorithm is efficient. 展开更多
关键词 Non-linear programming three term memory gradient method convergence non-monotone line search technique numerical experiment
下载PDF
Passive seismic velocity tomography on longwall mining panel based on simultaneous iterative reconstructive technique (SIRT) 被引量:13
13
作者 N.Hosseini K.Oraee +1 位作者 K.Shahriar K.Goshtasbi 《Journal of Central South University》 SCIE EI CAS 2012年第8期2297-2306,共10页
Mining operation, especially underground coal mining, always has the remarkable risks of ground control. Passive seismic velocity tomography based on simultaneous iterative reconstructive technique (SIRT) inversion is... Mining operation, especially underground coal mining, always has the remarkable risks of ground control. Passive seismic velocity tomography based on simultaneous iterative reconstructive technique (SIRT) inversion is used to deduce the stress redistribution around the longwall mining panel. The mining-induced microseismic events were recorded by mounting an array of receivers on the surface, above the active panel. After processing and filtering the seismic data, the three-dimensional tomography images of the p-wave velocity variations by SIRT passive seismic velocity tomography were provided. To display the velocity changes on coal seam level and subsequently to infer the stress redistribution, these three-dimensional tomograms into the coal seam level were sliced. In addition, the boundary element method (BEM) was used to simulate the stress redistribution. The results show that the inferred stresses from the passive seismic tomograms are conformed to numerical models and theoretical concept of the stress redistribution around the longwall panel. In velocity tomograms, the main zones of the stress redistribution around the panel, including front and side abutment pressures, and gob stress are obvious and also the movement of stress zones along the face advancement is evident. Moreover, the effect of the advance rate of the face on the stress redistribution is demonstrated in tomography images. The research result proves that the SIRT passive seismic velocity tomography has an ultimate potential for monitoring the changes of stress redistribution around the longwall mining panel continuously and subsequently to improve safety of mining operations. 展开更多
关键词 速度层析成像 地震数据 长壁开采 重建技术 面板 迭代 基础 无源
下载PDF
Monotone Iterative Method for Set valued Quasilinear Elliptic Boundary Value Problems
14
作者 孙乐林 徐迪红 +1 位作者 程建 李荣华 《Northeastern Mathematical Journal》 CSCD 2001年第1期5-8,共4页
关键词 set valued differential equation elliptic boundary value problem generalized monotone iteration
下载PDF
g-η-Monotone mapping and resolvent operator technique for solving generalized implicit variational-like inclusions
15
作者 张清邦 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第1期11-18,共8页
A new class of g-η-monotone mappings and a class of generalized implicit variational-like inclusions involving g-η-monotone mappings are introduced. The resolvent operator of g-η-monotone mappings is defined and it... A new class of g-η-monotone mappings and a class of generalized implicit variational-like inclusions involving g-η-monotone mappings are introduced. The resolvent operator of g-η-monotone mappings is defined and its Lipschitz continuity is presented, An iterative algorithm for approximating the solutions of generalized implicit wriational- like inclusions is suggested and analyzed. The convergence of iterative sequences generated by the algorithm is also proved, 展开更多
关键词 g-η-monotone mapping resolvent operator generalized implicit variational-like inclusion iterative algorithm
下载PDF
Nonlinear Algebraic Equations Solved by an Optimal Splitting-Linearizing Iterative Method
16
作者 Chein-Shan Liu Essam REl-Zahar Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1111-1130,共20页
How to accelerate the convergence speed and avoid computing the inversion of a Jacobian matrix is important in the solution of nonlinear algebraic equations(NAEs).This paper develops an approach with a splitting-linea... How to accelerate the convergence speed and avoid computing the inversion of a Jacobian matrix is important in the solution of nonlinear algebraic equations(NAEs).This paper develops an approach with a splitting-linearizing technique based on the nonlinear term to reduce the effect of the nonlinear terms.We decompose the nonlinear terms in the NAEs through a splitting parameter and then linearize the NAEs around the values at the previous step to a linear system.Through the maximal orthogonal projection concept,to minimize a merit function within a selected interval of splitting parameters,the optimal parameters can be quickly determined.In each step,a linear system is solved by the Gaussian elimination method,and the whole iteration procedure is convergent very fast.Several numerical tests show the high performance of the optimal split-linearization iterative method(OSLIM). 展开更多
关键词 Nonlinear algebraic equations novel splitting-linearizing technique iterative method maximal projection optimal splitting parameter
下载PDF
Technique for Estimating the Cone Bearing Smoothing Parameters
17
作者 Erick Baziw 《International Journal of Geosciences》 2023年第7期603-618,共16页
Cone penetration testing (CPT) is an extensively utilized and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic cone into penetrable soils and recordi... Cone penetration testing (CPT) is an extensively utilized and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic cone into penetrable soils and recording the resistance to the cone tip (q<sub>c</sub> value). The measured q<sub>c</sub> values (after correction for the pore water pressure) are utilized to estimate soil type and associated soil properties based predominantly on empirical correlations. The most common cone tips have associated areas of 10 cm<sup>2</sup> and 15 cm<sup>2</sup>. Investigators also utilized significantly larger cone tips (33 cm<sup>2</sup> and 40 cm<sup>2</sup>) so that gravelly soils can be penetrated. Small cone tips (2 cm<sup>2</sup> and 5 cm<sup>2</sup>) are utilized for shallow soil investigations. The cone tip resistance measured at a particular depth is affected by the values above and below the depth of interest which results in a smoothing or blurring of the true bearing values. Extensive work has been carried out in mathematically modelling the smoothing function which results in the blurred cone bearing measurements. This paper outlines a technique which facilitates estimating the dominant parameters of the cone smoothing function from processing real cone bearing data sets. This cone calibration technique is referred to as the so-called CPSPE algorithm. The mathematical details of the CPSPE algorithm are outlined in this paper along with the results from a challenging test bed simulation. 展开更多
关键词 Cone Penetration Testing (CPT) Geotechnical Site Characterization Optimal Estimation iterative Forward Modelling (IFM) Monte Carlo techniques Calibration
下载PDF
Revolution CT联合不同权重ASIR-V在胸痛三联征成像中的应用价值比较 被引量:1
18
作者 郑晓娜 周方丽 刘雅兰 《中国CT和MRI杂志》 2024年第4期55-58,共4页
目的探讨Revolution CT联合不同权重多模型迭代重建技术(ASIR-V)在胸痛三联征(TRO)成像中的应用价值。方法选取我院2022年8月~2023年3月收治的90例胸痛患者进行研究,入院后接受TRORevolution CT平扫。按随机数字表法分成滤波反投影(FBP... 目的探讨Revolution CT联合不同权重多模型迭代重建技术(ASIR-V)在胸痛三联征(TRO)成像中的应用价值。方法选取我院2022年8月~2023年3月收治的90例胸痛患者进行研究,入院后接受TRORevolution CT平扫。按随机数字表法分成滤波反投影(FBP)组与ASIR-V组各45例。FBP组采用FBP技术进行图像重组,ASIR-V组采用不同权重(10%、30%、50%、70%、90%)前置ASIR-V技术重组。记录两组辐射剂量长度乘积(DLP)、有效剂量(ED),比较不同重组方式及不同权重下冠状动脉、升主动脉、降主动脉、肺动脉干的平均CT值、噪声值、信噪比(SNR)、对比信噪比(CNR),由2名经验丰富的影像科医生进行主观图像质量评分。结果ASIR-V组DLP、ED低于FBP组(P<0.05)。ASIR-V不同权重的血管腔噪声值低于FBP,血管腔SNR、CNR与主观图像质量评分高于FBP(P<0.05)。ASIR-V权重50%、70%、90%的噪声值低于ASIR-V权重10%、30%的噪声值(P<0.05)。ASIR-V权重50%、70%、90%的SNR、CNR高于ASIR-V权重10%、30%的SNR、CNR(P<0.05)。ASIR-V权重50%、70%的主观评分高于ASIR-V权重10%、30%、90%的主观评分(P<0.05)。结论Revolution CT联合ASIR-V技术能减少辐射剂量,ASIR-V权重50%、70%时对血管腔与解剖结构的显示良好,血管腔噪声值较低,SNR、CNR较高,能满足诊断需求。 展开更多
关键词 胸痛三联征 权重 多模型迭代重建技术 Revolution CT
下载PDF
基于点云特征的城市道路标识线提取与分类
19
作者 郑帅锋 王山东 +1 位作者 张陈意 王伦炜 《激光技术》 CSCD 北大核心 2024年第1期27-33,共7页
为了解决基于车载激光雷达(LiDAR)点云数据中的道路标识线提取完整度与提取精确度方面数值偏低等问题,提出了一种基于点云多元特征的道路标识线快速提取方法。在城市道路标识线的强度信息、几何信息和语义信息基础上,结合路面点云的强... 为了解决基于车载激光雷达(LiDAR)点云数据中的道路标识线提取完整度与提取精确度方面数值偏低等问题,提出了一种基于点云多元特征的道路标识线快速提取方法。在城市道路标识线的强度信息、几何信息和语义信息基础上,结合路面点云的强度特征、高程特征和点密度特征,生成多个地理参考图像,对多元特征图像进行特征提取与填充,再利用Ostu算法以及Alpha shapes算法实现道路标识线点云精提取,并根据标识线的几何、语义信息和模型匹配方案实现标识线的细分类,进行了理论分析和实验验证,取得了澳大利亚某城市道路的点云数据。结果表明,提取的短虚线、斑马线、单向转向箭头、长虚线的准确率均高于96%,召回率均达到91%及以上,综合评价指标均达到94%及以上。这些结果对无人驾驶领域研究起到了添砖加瓦的作用,也为城市数字化建设提供了一定的参考价值。 展开更多
关键词 激光技术 标识线提取 多元特征 车载激光雷达点云 二值化 临近点迭代模板匹配
下载PDF
四阶两点边值问题n个对称正解的存在性
20
作者 李宪 达举霞 章欢 《华南师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期123-127,共5页
应用单调迭代法,研究了四阶两点边值问题u^((4))(t)=f(u(t))(t?[0,1]),u(0)=u(1)=0,u"(0)=u"(1)=0正解的存在性。在边值问题满足特定的条件下,证明了该问题存在n个对称正解。
关键词 四阶边值问题 格林函数 单调迭代法 对称正解
下载PDF
上一页 1 2 57 下一页 到第
使用帮助 返回顶部