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试论月龄历谱的数理结构及编排规则 被引量:10
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作者 李勇 《自然科学史研究》 CSSCI CSCD 北大核心 2001年第4期320-331,共12页
运用数理统计方法,借鉴天文历算及历谱编排的有关 知识,试图提供一种被称为月龄历谱的数理结构模型(数表),以作为对具有某些月龄特征的 词语的研究工具。其用途:(1)由 这些月龄词语的干支差直接得出它们可能的年代间隔;(... 运用数理统计方法,借鉴天文历算及历谱编排的有关 知识,试图提供一种被称为月龄历谱的数理结构模型(数表),以作为对具有某些月龄特征的 词语的研究工具。其用途:(1)由 这些月龄词语的干支差直接得出它们可能的年代间隔;(2)可用于编排相应的月龄历谱(如金 文历谱、某些甲骨文历谱等);(3)能对月龄历谱(如“夏商周断代工程”给出的西周金文历 谱)方案中月龄词语的月龄范 围及年代间隔进行误差分析。 展开更多
关键词 月龄词语 数理结构 历谱 年代 编排规则
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从数理角度论建筑生成的合理性
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作者 徐葛生 《建材与装饰》 2017年第19期49-49,共1页
本文旨在研讨建筑自主性理论,通过对于但丁纪念堂在建筑层面、室内空间层面的分析,总结建筑在数理层面上的自主性。
关键词 理性 数理结构 多维度
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广义矩估计的延伸——广义经验似然估计
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作者 张卫东 龚金国 《统计与信息论坛》 CSSCI 2012年第3期21-25,共5页
从广义矩估计(GMM)到广义经验似然估计(GEL)的发展,是由于GMM估计量小样本性质的不足,促使人们寻求方法的改进和拓展。通过必要的证明和推导,详细解析GEL类估计量(包括EL,ET,CUE)的逻辑关系和数理结构,认识GEL的内在本质,并运用随机模... 从广义矩估计(GMM)到广义经验似然估计(GEL)的发展,是由于GMM估计量小样本性质的不足,促使人们寻求方法的改进和拓展。通过必要的证明和推导,详细解析GEL类估计量(包括EL,ET,CUE)的逻辑关系和数理结构,认识GEL的内在本质,并运用随机模拟方法证实了在小样本场合GEL类估计量比GMM估计量具有更小的估计偏差和均方误差,即GEL类估计改进了GMM估计的小样本性质。 展开更多
关键词 广义矩估计 广义经验似然类估计量 数理结构 随机模拟
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黄金分割的美学意义及其应用 被引量:27
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作者 张雄 《自然辩证法研究》 CSSCI 北大核心 1999年第11期5-8,共4页
黄金分割在自然和社会中有着广泛的意义,从古到今始终被美学家作为形式美的一条法则。本文分析黄金分割的内在数理结构,从美学角度论述黄金分割的应用,然后分析黄金分割的美学意义。
关键词 黄金分割 美学意义 数理结构 审美
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证实“三种音阶”定论“同均三宫” 被引量:1
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作者 刘永福 《交响(西安音乐学院学报)》 2022年第3期11-17,共7页
“同均三宫”作为一个“律声系统”概念,包含“同均”与“三宫”两种内涵,前者强调“七律为均”,后者指代“三种音阶”。“黄钟一均惟用七律”等史料证明,“七律为均”及其律声系统关系,是中国古代乐学理论中的固有概念。运用逻辑思辨... “同均三宫”作为一个“律声系统”概念,包含“同均”与“三宫”两种内涵,前者强调“七律为均”,后者指代“三种音阶”。“黄钟一均惟用七律”等史料证明,“七律为均”及其律声系统关系,是中国古代乐学理论中的固有概念。运用逻辑思辨的方法,证实“三种音阶”的真实存在是解决“同均三宫”问题的根本和唯一。通过对乐学理论、数理结构、借调记谱、乐调实践的逻辑思辨及理论研究证实,“三种音阶”的存在具有无可争辩的学理依据和实践基础。 展开更多
关键词 同均三宫 七律为均 三种音阶 乐学理论 数理结构 借调记谱 乐调实践
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Structure Parameters and Physiological Indices Research of High-quality and High-yield Apple Orchards 被引量:1
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作者 薛晓敏 王翠玲 +2 位作者 王金政 孟海凤 聂佩显 《Agricultural Science & Technology》 CAS 2014年第11期1953-1956,1959,共5页
In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of ap... In order to research environment parameters and physiological indices of high-quality and high-yield apple trees, two orchards with young and mature apples trees were investigated to explore structural parameter of apple tree and community, and some physiological indices in fields and by room measurements. The results showed that tree height of high-quality orchard was in the range of 260 to 290 cm, branch angle in 70°-75°, and orchard coverage rate in 75%-94%, and the connec-tion rates between rows and trees were lower. Furthermore, the total branches of mature orchard reached 1.04 ×106 per hm2, while the young orchard was 8.79 ×105 per hm2; the leaves were thick and chlorophyl content was high, with SPAD value at 58.22. Additional y, the photosynthesis of the orchard was strong, and net photo-synthetic rate was 17.48-21.8 μmolCO2/(m2·s). The proportions of lateral shoot of bearing part were 81% and 75% respectively. 展开更多
关键词 High-quality and high-yield Apple orchard Structure parameters Physio-logical index
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Characteristics of Phytoplankton and Its Correlation with Water Environment in SFTWs 被引量:1
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作者 张丹 吴小慧 +4 位作者 黄民生 何岩 张勇 童敏 潘震 《Agricultural Science & Technology》 CAS 2011年第3期439-442,共4页
[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,ph... [Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration. 展开更多
关键词 SFTWs PHYTOPLANKTON Community structure Diversity index Physicochemical indexes
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关于大脑密码学的思维
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作者 叶眺新 《延边大学学报(社会科学版)》 1988年第4期19-21,共3页
一、意识的现代数理结构人的意识看来很神奇,其实大脑是和物质具有合一性的,不然大脑这种生态位就不会在自然进化中出现。为此我们可以将意识的数理结构,用三种模型本分解。(一)类似光谱变换的三旋自然密码,是意识在大脑物质里泛旋的第... 一、意识的现代数理结构人的意识看来很神奇,其实大脑是和物质具有合一性的,不然大脑这种生态位就不会在自然进化中出现。为此我们可以将意识的数理结构,用三种模型本分解。(一)类似光谱变换的三旋自然密码,是意识在大脑物质里泛旋的第一级编码机制。我国泛旋量子色动力学研究,认为夸克的颜色。 展开更多
关键词 密码学 大脑 数理结构 编码机制 谱变换 九连环 意识 三旋 有限自动机 生态位
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有奖征答第五期答案
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作者 刘欣 《新理财(公司理财)》 1995年第2期28-28,共1页
首先,替数在“河图”中体现极为明显:一六共宗、二七为朋、三八同道、四九为友、五十相守。其次,凑数和补数在“河图”中也可体现出来:按左下、右上相邻两个方位,内圈的数互为凑数,内外交叉的数互为补数。补数在“洛书”中看得更清楚:... 首先,替数在“河图”中体现极为明显:一六共宗、二七为朋、三八同道、四九为友、五十相守。其次,凑数和补数在“河图”中也可体现出来:按左下、右上相邻两个方位,内圈的数互为凑数,内外交叉的数互为补数。补数在“洛书”中看得更清楚:对应方位均为互补数。当然还可从其它方面分析以上数字关系。 利用“洛书”还可巧妙记忆“一口清”和乘方的个位积:如3的“一口清”可按1→3→9→7→1。 展开更多
关键词 补数 洛书 立方和 行计算 变式 开立方 乘除法 数理结构 著作权 极图
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《易经》变式速算与光波计算机
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作者 宇文永权 《新理财(公司理财)》 1995年第5期2-4,共3页
本文不但将古老的《易经》与笔者创立的“变式速算理论”在思维科学上建立了通路,而且进一步提出将“变式速算理论”与光波计算技术相结合的设想。“变式速算理论”及其速算方法是经国家鉴定属国际首创的速算科研成果;而将其与《易经》... 本文不但将古老的《易经》与笔者创立的“变式速算理论”在思维科学上建立了通路,而且进一步提出将“变式速算理论”与光波计算技术相结合的设想。“变式速算理论”及其速算方法是经国家鉴定属国际首创的速算科研成果;而将其与《易经》在理论上建立联系亦属笔者首次提出;用光波计算代替电子计算是笔者提出的一种新设想;如将“变式速算理论”与光波计算技术相结合并获得成功,将会对人类的文明和进步产生重大影响。 展开更多
关键词 《易经》 计算机 变式 电子计算 超大规模集成电路 计算技术 速算法 转化图 现代科学 数理结构
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Electronic Structure Research on Lattice Stability of V, Nb, and Ta by Density Functional Theory
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作者 陶辉锦 万芳铭 陈伟民 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期69-72,I0002,共5页
The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, an... The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Lattice constants, total energies, and densities of states of these metals were calculated using the plane-wave pseudopotential method in DFT. Results were compared with those of projector augmented wave method, CALPHAD method, and experiments. Total energy and electronic structure analyses showed that valence electrons mostly transferred from s to p or d state, changing obviously with both the crystal structure and the elemental period number from V to Ta and leading to stronger cohesion, higher cohesive energy and more stable lattice of heavier metals. 展开更多
关键词 V NB TA Lattice stability Density functional theory
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Adsorption Isotherm and Kinetics of Dibenzofuran on Granular Activated Carbons 被引量:7
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作者 李湘 李忠 罗灵爱 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期701-704,共4页
The adsorption of dibenzofuran on three commercial granular activated carbons (ACs) was investigated by dynamic experiment to correlate the adsorption equilibrium and kinetics with the structure of activated carbons.P... The adsorption of dibenzofuran on three commercial granular activated carbons (ACs) was investigated by dynamic experiment to correlate the adsorption equilibrium and kinetics with the structure of activated carbons.Physical properties including surface area, average pore diameter, micropore area and micropore volume of the activated carbons were characterized by N2 adsorption experiment on ASAP2010. To calculate the adsorption parameters, adsorption isotherm data were fitted to the Langmuir equation, and adsorption kinetic data were fitted to the linear driving force (LDF) diffusion model. From the correlation results, it is concluded that the adsorption equilibrium and diffusion coefficient of dibenzofuran on activated carbon are controlled respectively by the total adsorbent surface area and the adsorbent pore diameter. 展开更多
关键词 adsorption isotherm diffusion coefficient physical structure DIBENZOFURAN activated carbons
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Optimal design of structural parameters for shield cutterhead based on fuzzy mathematics and multi-objective genetic algorithm 被引量:12
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作者 夏毅敏 唐露 +2 位作者 暨智勇 程永亮 卞章括 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期937-945,共9页
In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters ... In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters for shield cutterhead is formulated,based on the complex engineering technical requirements. In the model, as the objective function of the model is a composite function of the strength and stiffness, the response surface method is applied to formulate the approximate function of objective function in order to reduce the solution scale of optimal problem. A multi-objective genetic algorithm is used to solve the cutterhead structure design problem and the change rule of the stress-strain with various structural parameters as well as their optimal values were researched under specific geological conditions. The results show that compared with original cutterhead structure scheme, the obtained optimal scheme of the cutterhead structure can greatly improve the strength and stiffness of the cutterhead, which can be seen from the reduction of its maximum equivalent stress by 21.2%, that of its maximum deformation by 0.75%, and that of its mass by 1.04%. 展开更多
关键词 shield tunneling machine cutterhead structural parameters fuzzy mathematics finite element optimization
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PARALLEL REGION PRESERVING MULTISECTION METHOD FOR SOLVING GENERALIZED EIGENPROBLEM 被引量:1
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作者 曾岚 周树荃 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期51+46-50,共6页
The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of ... The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of symmetric tridiagonal matrix. The multisection method for solving the generalized eigenproblem applied significantly in many science and engineering domains has not been studied. The parallel region preserving multisection method (PRM for short) for solving generalized eigenproblems of large sparse and real symmetric matrix is presented in this paper. This method not only retains the advantages of the conventional determinant search method (DS for short), but also overcomes its disadvantages such as leaking roots and disconvergence. We have tested the method on the YH 1 vector computer, and compared it with the parallel region preserving determinant search method the parallel region preserving bisection method (PRB for short). The numerical results show that PRM has a higher speed up, for instance, it attains the speed up of 7.7 when the scale of the problem is 2 114 and the eigenpair found is 3, and PRM is superior to PRB when the scale of the problem is large. 展开更多
关键词 parallel processing structural analysis numerical algebra generalized eigenproblem parallel multisection method
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Fatigue damage reliability analysis for Nanjing Yangtze river bridge using structural health monitoring data 被引量:2
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作者 何旭辉 陈政清 +1 位作者 余志武 黄方林 《Journal of Central South University of Technology》 EI 2006年第2期200-203,共4页
To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural ... To evaluate the fatigue damage reliability of critical members of the Nanjing Yangtze river bridge, according to the stress-number curve and Miner’s rule, the corresponding expressions for calculating the structural fatigue damage reliability were derived. Fatigue damage reliability analysis of some critical members of the Nanjing Yangtze river bridge was carried out by using the strain-time histories measured by the structural health monitoring system of the bridge. The corresponding stress spectra were obtained by the real-time rain-flow counting method. Results of fatigue damage were calculated respectively by the reliability method at different reliability and compared with Miner’s rule. The results show that the fatigue damage of critical members of the Nanjing Yangtze river bridge is very small due to its low live-load stress level. 展开更多
关键词 fatigue damage reliability evaluation railway steel bridge structural health monitoring real-time rainflow counting method
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Impacts of Secondary Aerosols on a Persistent Fog Event in Northern China 被引量:6
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作者 JIA Xing-Can GUO Xue-Liang 《Atmospheric and Oceanic Science Letters》 2012年第5期401-407,共7页
The chemistry version of the Weather Re- search and Forecasting model (WRF/Chem) was coupled with the anthropogenic emission inventory of David Streets to investigate the impacts of secondary aerosols on a persisten... The chemistry version of the Weather Re- search and Forecasting model (WRF/Chem) was coupled with the anthropogenic emission inventory of David Streets to investigate the impacts of secondary aerosols on a persistent fog event from 25 to 26 October 2007, in Northem China. The spatial distribution of the simulated fog is consistent with satellite observations, and the time-height distributions of the simulated boundary layer where the fog formed are also in good agreement with these observations. The sensitivity studies show that the secondary aerosols of SO4, NO3, and NH4 formed from gaseous precursors of SO2, NOx, and NH3 had substantial impacts on the formation processes and microphysical structure of the fog event. The decrease of the secondary aerosols obviously reduced the liquid water path and column droplet number concentration of the fog below the 1-km layer, and the corresponding area-averaged liquid water path and droplet number concentration of the fog decreased by 43% and 79%, respectively. The concentra- tions of NOx and NO3 were found to be extremely high in this case. The concentration of interstitial aerosol NO3 was much higher than the SO4 and NH4, but the concentration of SO4 was highest in the cloud-borne aerosols. The average activation ratios for SO4, NO3, and NH4 were 34%, 31%, and 30%, respectively, and the maximum ra- tios reached 62%, 86%, and 55% during the fog episode. 展开更多
关键词 secondary aerosol FOG WRF/Chem simulation
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A METHODOLOGY FOR INTEGRATED MANAGEMENT SYSTEM
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作者 陈旭球 叶伟雄 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第1期111-115,共5页
ISO 9000 certification has been considered as an effective competitive edge for manufacturing industries. In Hong Kong, the ISO 9000 certification has been widely adopted and extended to service industries for the so... ISO 9000 certification has been considered as an effective competitive edge for manufacturing industries. In Hong Kong, the ISO 9000 certification has been widely adopted and extended to service industries for the sole purpose of enhancing corporate image. However, complaints have been voiced by many certified organizations about increasing paperwork, non direct labour and excessive resources channelled into non core business. This paper is to propound the integrated management system, a single management system focusing on business purpose yet being flexible enough to integrate the requirements of various management standards such as the ISO 9000, ISO 14000 and future ISO 18000. This paper describes how the proposed system could be implemented to achieve the desired business results. 展开更多
关键词 quality management integrated management system integrated documentation structure
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Prolongation Structure of Semi-discrete Nonlinear Evolution Equations 被引量:6
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作者 BAI Yong-Qiang WU Ke +1 位作者 GUO Han-Ying ZHAO Wei-Zhong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4X期591-600,共10页
Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSding... Based on noncommutative differential calculus, we present a theory of prolongation structure for semidiscrete non/inear evolution equations. As an illustrative example, a semi-discrete model of the non/inear SchrSdinger equation is discussed in terms of this theory and the corresponding Lax pairs are also given. 展开更多
关键词 noncommutative differential calculus prolongation structure Lax pair
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Quotient space model based on algebraic structure 被引量:3
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作者 陈林书 WangJiayang +1 位作者 LiLi YangZhenghua 《High Technology Letters》 EI CAS 2016年第2期160-169,共10页
In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure i... In the quotient space theory of granular computing,the universe structure is assumed to be a topology,therefore,its application is still limited.In this study,based on the quotient space model,the universe structure is assumed as an algebra instead of a topology.As to obtain the algebraic quotient operator,the granulation must be uniquely determined by a congruence relation,and all the congruence relations form a complete semi-order lattice,which is the theoretical basis of granularities ' completeness.When the given equivalence relation is not a congruence relation,it defines the concepts of upper quotient and lower quotient,and discusses some of their properties which demonstrate that falsity preserving principle and truth preserving principle are still valid.Finally,it presents the algorithms and example of upper quotient and lower quotient.The work extends the quotient space theory from structure,and provides theoretical basis for the combination of the quotient space theory and the algebra theory. 展开更多
关键词 granular computing quotient space congruence closure quotient operation up-per lower quotient
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Orbital-Free Density Functional Theory for Molecular Structure Calculations 被引量:1
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作者 Huajie Chen Aihui Zhou 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2008年第1期1-28,共28页
We give here an overview of the orbital-flee density functional theory that is used for modeling atoms and molecules. We review typical approximations to the kinetic energy, exchange-correlation corrections to the k... We give here an overview of the orbital-flee density functional theory that is used for modeling atoms and molecules. We review typical approximations to the kinetic energy, exchange-correlation corrections to the kinetic and Hartree energies, and constructions of the pseudopotentials. We discuss numerical discretizations for the orbital-free methods and include several numerical results for illustrations. 展开更多
关键词 Density functional theory molecular structure numerical discretization orbital-free
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