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贝叶斯正规化算法在油藏参数拟合方面的应用
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作者 潘永才 单文兵 +1 位作者 张尚辉 王富 《物联网技术》 2012年第4期45-47,共3页
通过已知测井资料对油藏储量进行预测,是目前石油行业一个重要的研究课题。文章介绍了一种基于贝叶斯正规化算法的BP神经网络,并把网络应用到油藏参数拟合过程中的具体方法,该方法对提高石油生产效率、降低成本具有很大的作用。
关键词 油藏 拟合 贝叶斯 正规算法 神经网络
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稀疏有限元线性系统的并行算法实现
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作者 张哲 《计算机工程与应用》 CSCD 北大核心 2010年第29期47-49,52,共4页
在对称多处理机系统上,提出了一种求解稀疏对称有限元线性系统的正规化精确并行逆算法。该算法以一种避免数据依赖的反对角运动方法为基础,使用OpenMP编译指导来实现。诸如加速比和效率等数值实验结果的推出,说明在一个对称多处理机系统... 在对称多处理机系统上,提出了一种求解稀疏对称有限元线性系统的正规化精确并行逆算法。该算法以一种避免数据依赖的反对角运动方法为基础,使用OpenMP编译指导来实现。诸如加速比和效率等数值实验结果的推出,说明在一个对称多处理机系统上,所提出的算法求解方法能更好地提高性能,获得更大的加速。 展开更多
关键词 稀疏线性系统 正规化精确并行逆算法 OPENMP
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一种改进的大规模MIMO线性预编码算法 被引量:3
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作者 张继荣 吕沙沙 《西安邮电大学学报》 2018年第2期12-16,共5页
为了降低预编码算法在大规模多输入多输出(multiple input multiple output,MIMO)系统下的误码率及复杂度,提出了一种改进的块对角化(block diagonalization,BD)预编码算法。该算法将正规迫零(regular zero forcing,RZF)预编码算法的预... 为了降低预编码算法在大规模多输入多输出(multiple input multiple output,MIMO)系统下的误码率及复杂度,提出了一种改进的块对角化(block diagonalization,BD)预编码算法。该算法将正规迫零(regular zero forcing,RZF)预编码算法的预编码矩阵作为信道矩阵的伪逆,然后采用了复杂度较低的正三角(orthogonal triangular,QR)分解代替原BD算法的奇异值(singularly valuable decomposition,SVD)分解求平行单用户的等效信道,最终求得预编码矩阵。仿真结果表明,当基站配备128根天线,用户数为61时,改进算法的误码率及复杂度分别为0.109 5、1.379×10~8,较优化的块对角化(optimized block diagonalization,OBD)预编码算法的误码率及复杂度分别降低了11.5%和1.031×10^(10)。提出的改进算法可应用于大规模MIMO系统中。 展开更多
关键词 大规模多输入多输出 块对角化预编码算法 正规迫零预编码算法
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建立联系 培养数感——读《如何培养学生的数感》一书有感 被引量:1
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作者 韩东 《小学教学(数学版)》 2017年第12期56-57,共2页
《数学课程标准(2011)》指出:“数感主要是指关于数与数量、数量关系、运算结果估计等方面的感悟。建立数感有助于学生理解现实生活中数的意义,理解或表述具体情境中的数量关系。”初读这段话,我并不是特别明白其中的道理,总觉得有... 《数学课程标准(2011)》指出:“数感主要是指关于数与数量、数量关系、运算结果估计等方面的感悟。建立数感有助于学生理解现实生活中数的意义,理解或表述具体情境中的数量关系。”初读这段话,我并不是特别明白其中的道理,总觉得有种说不出的感觉。当我读完《如何培养学生的数感》([英]朱莉娅·安吉莱瑞著;徐文彬译)一书后,终于对数感有了感悟,它是一个人对数字和运算的一种灵活运用的倾向和能力。 展开更多
关键词 数量关系 具体情境 运算结果 现实生活 安吉 朱莉娅 人教版教材 课程标准 正规算法 特定情境
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贝叶斯改进BP神经网络在织物染色配色中的应用 被引量:1
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作者 聂晴晴 张秉森 +3 位作者 李含春 王巍娟 韩蔚 司学锋 《青岛大学学报(工程技术版)》 CAS 2008年第4期45-49,共5页
针对BP算法及其改进算法泛化能力不强的问题,探讨了用贝叶斯正规化算法与LM算法的结合来提高BP神经网络的泛化能力。结果表明,在相同网络规模或误差条件下,贝叶斯正规化算法泛化能力明显优于基本BP算法及其它改进的BP算法,且收敛速度较... 针对BP算法及其改进算法泛化能力不强的问题,探讨了用贝叶斯正规化算法与LM算法的结合来提高BP神经网络的泛化能力。结果表明,在相同网络规模或误差条件下,贝叶斯正规化算法泛化能力明显优于基本BP算法及其它改进的BP算法,且收敛速度较快。因此文中把贝叶斯正规化算法与LM算法结合应用到了织物染色的计算机配色中,其预测的配方和实验的数据比较接近,证明了该方法的可行性。 展开更多
关键词 BP算法 贝叶斯正规算法 LM算法 计算机配色
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Several Properties of p-w-hyponormal Operators 被引量:1
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作者 LI Hai-ying YANG Chang-sen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期195-201,共7页
In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operat... In this paper, let T be a bounded linear operator on a complex Hilbert H. We give and prove that every p-w-hyponormal operator has Bishop's property(β) and spectral properties; Quasi-similar p-w-hyponormal operators have equal spectra and equal essential spectra. Finally, for p-w-hyponormal operators, we give a kind of proof of its normality by use of properties of partial isometry. 展开更多
关键词 Aluthge transformation Bishop's property(β) quasi-similar w-hyponormal operators p-w-hyponormal operators
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An analysis method for correlation between catenary irregularities and pantograph-catenary contact force 被引量:1
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作者 秦勇 张媛 +2 位作者 程晓卿 贾利民 邢宗义 《Journal of Central South University》 SCIE EI CAS 2014年第8期3353-3360,共8页
Pantograph-catenary contact force provides the main basis for evaluation of current quality collection; however,the pantograph-catenary contact force is largely affected by the catenary irregularities.To analyze the c... Pantograph-catenary contact force provides the main basis for evaluation of current quality collection; however,the pantograph-catenary contact force is largely affected by the catenary irregularities.To analyze the correlated relationship between catenary irregularities and pantograph-catenary contact force,a method based on nonlinear auto-regressive with exogenous input(NARX) neural networks was developed.First,to collect the test data of catenary irregularities and contact force,the pantograph/catenary dynamics model was established and dynamic simulation was conducted using MATLAB/Simulink.Second,catenary irregularities were used as the input to NARX neural network and the contact force was determined as output of the NARX neural network,in which the neural network was trained by an improved training mechanism based on the regularization algorithm.The simulation results show that the testing error and correlation coefficient are 0.1100 and 0.8029,respectively,and the prediction accuracy is satisfactory.And the comparisons with other algorithms indicate the validity and superiority of the proposed approach. 展开更多
关键词 catenary irregularities pantograph-catenary contact force NARX neural networks correlation analysis
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A predictor-corrector interior-point algorithmfor monotone variational inequality problems 被引量:2
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作者 梁昔明 钱积新 《Journal of Zhejiang University Science》 CSCD 2002年第3期321-325,共5页
Mehrotra's recent suggestion of a predictor corrector variant of primal dual interior point method for linear programming is currently the interior point method of choice for linear programming. In this work t... Mehrotra's recent suggestion of a predictor corrector variant of primal dual interior point method for linear programming is currently the interior point method of choice for linear programming. In this work the authors give a predictor corrector interior point algorithm for monotone variational inequality problems. The algorithm was proved to be equivalent to a level 1 perturbed composite Newton method. Computations in the algorithm do not require the initial iteration to be feasible. Numerical results of experiments are presented. 展开更多
关键词 Variational inequality problems(VIP) Predictor corrector interior point algorithm Numerical experiments
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Efficient multiuser detector based on box-constrained dichotomous coordinate descent and regularization 被引量:1
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作者 全智 刘杰 《Journal of Central South University》 SCIE EI CAS 2012年第6期1570-1576,共7页
The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated... The presented iterative multiuser detection technique was based on joint deregularized and box-constrained solution to quadratic optimization with iterations similar to that used in the nonstationary Tikhonov iterated algorithm.The deregularization maximized the energy of the solution,which was opposite to the Tikhonov regularization where the energy was minimized.However,combined with box-constraints,the deregularization forced the solution to be close to the binary set.It further exploited the box-constrained dichotomous coordinate descent algorithm and adapted it to the nonstationary iterative Tikhonov regularization to present an efficient detector.As a result,the worst-case and average complexity are reduced down as K2.8 and K2.5 floating point operation per second,respectively.The development improves the "efficient frontier" in multiuser detection,which is illustrated by simulation results.In addition,most operations in the detector are additions and bit-shifts.This makes the proposed technique attractive for fixed-point hardware implementation. 展开更多
关键词 dichotomous coordinate descent de-regularization low complexity multiuser detection Tikhonov regularization
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BP神经网络技术在城市建筑热环境研究中的应用
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作者 李宁 刘金祥 +2 位作者 陈晓春 李雅昕 丁高 《建筑科学》 北大核心 2010年第2期103-107,共5页
本文针对现代城市中越来越严重的热岛现象与能源问题,首先分析了北京市近60年的温度资料,可知60年来城区内的年平均温度升高了2.28℃,温度增幅为0.38℃/10 a。而后综合考虑城市建筑热环境的各种影响因素,利用BP神经网络技术建立了城市... 本文针对现代城市中越来越严重的热岛现象与能源问题,首先分析了北京市近60年的温度资料,可知60年来城区内的年平均温度升高了2.28℃,温度增幅为0.38℃/10 a。而后综合考虑城市建筑热环境的各种影响因素,利用BP神经网络技术建立了城市尺度下针对建筑热环境(温度)的预测模型,并对以往的数学模型和计算方法进行了改进。在改进后的预测模型中,通过枚举法选择隐含层最佳神经元个数,用贝叶斯正规化算法进行了网络训练,结果表明:与BP神经网络基本的L-M优化算法相比,该算法有较高的泛化能力和准确性,更适合于这一问题的研究。 展开更多
关键词 城市建筑热环境 温度增幅 BP神经网络 隐含层最佳神经元个数 贝叶斯正规算法
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Properties and Iterative Methods for the Lasso and Its Variants 被引量:6
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作者 Hong-Kun XU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第3期501-518,共18页
The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this pape... The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this paper some basic properties of the lasso and two variants of it are exploited. Moreover, the proximal method and its variants such as the relaxed proximal algorithm and a dual method for solving the lasso by iterative algorithms are presented. 展开更多
关键词 Lasso Elastic net Smooth-lasso l1 regulaxization SPARSITY Proximalmethod Dual method Projection THRESHOLDING
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A SECOND ORDER MEHROTRA-TYPE PREDICTOR-CORRECTOR ALGORITHM FOR SEMIDEFINITE OPTIMIZATION 被引量:4
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作者 Mingwang ZHANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2012年第6期1108-1121,共14页
Abstract Mehrotra-type predictor-corrector algorithm is one of the most effective primal-dual interior- point methods. This paper presents an extension of the recent variant of second order Mehrotra-type predictor-cor... Abstract Mehrotra-type predictor-corrector algorithm is one of the most effective primal-dual interior- point methods. This paper presents an extension of the recent variant of second order Mehrotra-type predictor-corrector algorithm that was proposed by Salahi, et a1.(2006) for linear optimization. Basedon the NT direction as Newton search direction, it is shown that the iteration-complexity bound of thealgorithm for semidefinite optimization is which is similar to that of the correspondingalgorithm for linear optimization. 展开更多
关键词 Mehrotra-Type algorithm polynomial complexity predictor-corrector algorithm semidef-inite optimization.
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Learning rates of regularized regression on the unit sphere 被引量:2
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作者 CAO FeiLong LIN ShaoBo +1 位作者 CHANG XiangYu XU ZongBen 《Science China Mathematics》 SCIE 2013年第4期861-876,共16页
This paper addresses the learning algorithm on the unit sphere.The main purpose is to present an error analysis for regression generated by regularized least square algorithms with spherical harmonics kernel.The exces... This paper addresses the learning algorithm on the unit sphere.The main purpose is to present an error analysis for regression generated by regularized least square algorithms with spherical harmonics kernel.The excess error can be estimated by the sum of sample errors and regularization errors.Our study shows that by introducing a suitable spherical harmonics kernel,the regularization parameter can decrease arbitrarily fast with the sample size. 展开更多
关键词 SPHERE regularized regression spherical harmonics kernel rate of convergence
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