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影响径向基神经网络分类性能的因素 被引量:8
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作者 王晓茹 《吉林大学学报(信息科学版)》 CAS 2009年第2期191-194,共4页
为进一步提高径向基神经网络超光谱图像分类的精度与效率,研究了径向基神经网(RBFN:Radical Basis Function Network)的径向基函数分布密度和输入数据归一化形式对分类结果的影响。通过计算机仿真实验,绘出了径向基函数分布密度和输入... 为进一步提高径向基神经网络超光谱图像分类的精度与效率,研究了径向基神经网(RBFN:Radical Basis Function Network)的径向基函数分布密度和输入数据归一化形式对分类结果的影响。通过计算机仿真实验,绘出了径向基函数分布密度和输入数据归一化形式对分类过程训练精度与测试精度影响规律曲线,为径向基神经网络在模式识别中的应用提供指导。 展开更多
关键词 归一化 径向函数分布密度 分类
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制动器制动最高温度径向基神经网络预测 被引量:2
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作者 季景方 闫滕滕 王振雨 《汽车实用技术》 2018年第16期55-57,共3页
神经网络具有智能化和快速学习能力,在复杂动态系统预测方面具有十分广泛的应用,文章基于径向基函数神经网络,对制动器制动最高温度预测问题进行了研究。通过仿真模拟验证了径向基函数神经网络在逼近与预测方面的强大功能,同时通过对径... 神经网络具有智能化和快速学习能力,在复杂动态系统预测方面具有十分广泛的应用,文章基于径向基函数神经网络,对制动器制动最高温度预测问题进行了研究。通过仿真模拟验证了径向基函数神经网络在逼近与预测方面的强大功能,同时通过对径向基函数分布密度的优化得到了用于制动器制动最高温度预测的神经网络预测系统,同时对制动温度的预测,得到了精度较高的预测结果。文章的研究对于制动器制动性能预测具有一定的参考。 展开更多
关键词 径向神经网络 制动器 预测模型 径向函数分布密度
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原子轨道指数的计算
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作者 王干全 余向阳 张翠玉 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第S1期64-66,共3页
用自洽场计算原子轨道波函数,将其平方后对角度部分积分得到原子的径向密度函数,将有电子占据轨道的径向密度函数加和得到原子总的径向密度函数.用类氢原子轨道的平方对角度部分积分后得到的径向密度函数作为基函数,拟合原子总的径... 用自洽场计算原子轨道波函数,将其平方后对角度部分积分得到原子的径向密度函数,将有电子占据轨道的径向密度函数加和得到原子总的径向密度函数.用类氢原子轨道的平方对角度部分积分后得到的径向密度函数作为基函数,拟合原子总的径向密度函数,即可得到原子轨道指数. 展开更多
关键词 密度函数 密度基函数 电荷分布 最小二乘法
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THE THEORETICAL STUDY OF ADSORPTION OF METAL IONS ON CHITOSAN 被引量:3
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作者 LU Renqing ZHANG Hongyu +1 位作者 QIU Guangmin LIU Chenguang 《Chinese Journal of Reactive Polymers》 2005年第1期76-81,共6页
The interactions between metal ions such as Zn2+, Pb2+, Mn2+, Hg2+, Cd2+, Ni2+ and chitosan have been investigated using the model cluster model method and density functional method. Full optimization and frequency an... The interactions between metal ions such as Zn2+, Pb2+, Mn2+, Hg2+, Cd2+, Ni2+ and chitosan have been investigated using the model cluster model method and density functional method. Full optimization and frequency analysis of all cluster models have been performed employing B3LYP hybrid method at 3-21G basis set level except metal ions which were invoked to use effective core potential (ECP) method. The energy changes, and the main structural parameters have been obtained during the theoretical study of the adsorption of metal ions on the chitosan. The calculations showed that the coordination modes of metal ions with chitosan models were different, the geometries of Mn2+, Zn2+, Cd2+, Hg2+, Pb2+ ions coordinated with two nitrogen atoms and two oxygen atoms were distorted tetrahedral, while the square planar structure of Ni2+ coordinated two nitrogen atoms and two oxygen atoms was observed. The heat of reaction between six metal ions and chitosan models showed the order: Mn2+ >Ni2+ >Zn2+ >Pb2+ >Hg2+ >Cd2+, this suggested that the coordination strength of Mn2+ >Ni2+ >Zn2+ >Pb2+ >Hg2+ >Cd2+. 展开更多
关键词 Density functional theory Basis set Effective core potential Chitosan Metal ions.
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Four-Electron Quantum Ring in a Magnetic Field
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作者 刘益民 刘荣万 +1 位作者 黄钢明 康帅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1177-1180,共4页
We study a quantum ring (QR) with four electrons in a perpendicular external magnetic field B by exact diagonalization. The low-lying spectra of the QR as a function orb are obtained. A phase diagram is presented in... We study a quantum ring (QR) with four electrons in a perpendicular external magnetic field B by exact diagonalization. The low-lying spectra of the QR as a function orb are obtained. A phase diagram is presented indicating that the angular momentum and the spin of the ground state of the QR may jump when B and/or the radius of the QR vary, and a corresponding analysis is performed. By plotting the density functions of the QR, the ground-state configuration is found to be a regular quadrangle. Furthermore, the features of the ground-state persistent current are revealed. 展开更多
关键词 quantum ring magnetic field ground state phase diagram
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Crystal Structure and Geometry-Optimization Study of N-(2-hydroxy-1-naphthaldene)-4-aminoantipyrine
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作者 GUO Feng BI Caifeng FAN Yuhua WANG Aidong XU Jiakun ZHANG Xia 《Journal of Ocean University of China》 SCIE CAS 2008年第2期166-170,共5页
N-(2-hydroxy-l-naphthaldene)-4-aminoantipyrine has been synthesized. The structure is determined by X-ray diffraction method and elemental analysis. The crystal system belongs to orthorhombic space group P(2)2(1... N-(2-hydroxy-l-naphthaldene)-4-aminoantipyrine has been synthesized. The structure is determined by X-ray diffraction method and elemental analysis. The crystal system belongs to orthorhombic space group P(2)2(1)2(1). The geometry has been ob- tained from the density functional theory (DFT) method and the B3LYP method employing the 6-31G^* basis sets. The calculated results propose that the latter is close to the experimental data. The structural parameters from the theory are close to those of the crystal and the calculated total energy of coordination is -31677.172 eV. The energy of HOMO and LUMO and the energy gap are 5.179 eV, -1.603 eV and 3.577 eV, respectively. 展开更多
关键词 Schiff base crystal structure density functional theory geometry-optimization
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DFT Calculation of Room Temperature Ionic Liquid 1-Ethyl-3-Methyl-Imidazolium Chlorocuprate (Ⅰ)
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作者 Lü Renqing Cao Zuogang (College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Dongying 257061) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2008年第1期55-62,共8页
The density functional theory (DFT) has been employed to investigate the electronic structures ofEMIM^+(1-ethyl-3-methylimidazolium+), CuCl2^-, Cu2Cl3^- and EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^- pairs. Full optimiza... The density functional theory (DFT) has been employed to investigate the electronic structures ofEMIM^+(1-ethyl-3-methylimidazolium+), CuCl2^-, Cu2Cl3^- and EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^- pairs. Full optimization and frequency analyses of EMIM^+, CuCl2^-, Cu2Cl3^-, eight initial EMIM^+-CuCl2^-, and six initial EMIM^+-Cu2Cl3^- geometries have been carried out using Gaussian-94 software-package at 6-3 I+G (d, p) basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^+-CuCl2^-, EMIM^+-Cu2Cl3^- pairs, single EMIM^+, CuCl2^-, and Cu2Cl3^- have been comparatively studied. The calculated results showed that the optimized EMIM^+-CuCl2^- pair conformer of the lowest energy was five ring moiety parallel to CuCl2^- plane with a distance of around 3.5,A, while EMIM^+-Cu2Cl3^- pair conformer of the lowest energy was five ring moiety of EMIM^+ perpendicular to Cu2Cl3^- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^+. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^+, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^+-CuCl2^-, and EMIM^+-Cu2Cl3^- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan. 展开更多
关键词 ionic liquid density functional theory 1-ethyl-3-methylimidazolium chlorocuprate (I)
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Georgian Social Insurance Fund Management Problems and Probabilistic and Statistical Analysis of Fund Capital Management
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作者 Nino Svanidze Asie Tsintsadze 《Journal of Mathematics and System Science》 2013年第10期508-513,共6页
A mathematical model of management of a social insurance fund with exponential insurance reimburse and financing determined social programs is represented and analyzed; A probability density function and fund's funct... A mathematical model of management of a social insurance fund with exponential insurance reimburse and financing determined social programs is represented and analyzed; A probability density function and fund's functioning probabilistic characteristics are obtained, that makes it possible to determine the sufficiency of fund capital at all levels of its management. With the help of conclusion it is possible for particular period of time determine in insurance fund change of cash flow movement speed, on what basis in determined from state tax revenues assigns acceptance necessity and capacity. 展开更多
关键词 Insurance reimburse probability distribution fund capital probability of insolvency
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