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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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Study and Practice on the Sponge City Construction Based on the Old Industrial Bases:Sponge City Construction in Xuzhou City
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作者 WANG Haiyang 《Journal of Landscape Research》 2024年第6期17-22,共6页
The old industrial base city is in the important strategic period of old industrial bases revitalization,resource-exhausted city transformation and development,and the construction of sponge city which can absorb,pene... The old industrial base city is in the important strategic period of old industrial bases revitalization,resource-exhausted city transformation and development,and the construction of sponge city which can absorb,penetrate,conserve,and purify is imperative.Based on the experimental sponge city of Xuzhou,this paper analyzes the problems of the old industrial base city.Combined with the existing work foundation,the objectives and guiding principles of Xuzhou sponge city construction are proposed.And the four ways are implemented to improve the status quo of the old industrial base,to effectively carry out the sponge city construction characterized by the old industrial bases. 展开更多
关键词 Old industrial bases XUZHOU Sponge city
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Research on the Construction and Development of Aesthetic Education Bases in Higher Education Institutions
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作者 Wei Zhou 《Journal of Contemporary Educational Research》 2024年第10期48-53,共6页
In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical... In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical activities centered on aesthetic education.Strengthening the foundation of aesthetic education theory,addressing practical challenges in the teaching process,and closely linking research with teaching will create a feedback loop that benefits drama education.This article provides an in-depth analysis of the construction strategies,resource advantages and disadvantages,and development of aesthetic education bases,offering countermeasures and suggestions for their construction in universities.It aims to provide a solid research foundation for the growth and development of aesthetic education bases in higher education institutions. 展开更多
关键词 Aesthetic education Educational base Construction and development
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Homogenization Construction of Three-Level Teaching Bases for General Practice Medicine Under the Internet+Model
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作者 Yu Cai Ge Wu +3 位作者 Yuanyuan Jia Siqi Wang Chang Tian Yu Feng 《Journal of Contemporary Educational Research》 2024年第5期46-52,共7页
With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching l... With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching levels among different bases.Most clinical teaching bases have incomplete teaching management systems,inadequate teaching management institutions,insufficient teaching personnel,and inadequate implementation of teaching rules and regulations.This article combines the construction practice of three-level clinical teaching base of the General Medicine College and the First Affiliated Hospital of Xi’an Medical University.We establish a standardized management system for the three-level clinical teaching base;implement a teaching supervision system and strengthen the monitoring of teaching quality;adopt multiple evaluations to test the effectiveness of clinical teaching implementation;explore the path of homogenization construction of teaching bases in terms of unified teacher training,promoting the development of teacher teaching abilities with equal quality and excellence,and providing a reference for improving the quality of medical talent training. 展开更多
关键词 Clinical teaching base Homogenization construction General practice medicine
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Integrated Sensing and Communication Enabled Sensing Base Station:System Design,Beamforming,Interference Cancellation and Performance Analysis
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作者 Jiang Wangjun Wei Zhiqing +1 位作者 Feng Zhiyong Chen Xu 《China Communications》 2025年第1期111-127,共17页
This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrate... This paper studies the sensing base station(SBS)that has great potential to improve the safety of vehicles and pedestrians on roads.SBS can detect the targets on the road with communication signals using the integrated sensing and communication(ISAC)technique.Compared with vehicle-mounted radar,SBS has a better sensing field due to its higher deployment position,which can help solve the problem of sensing blind areas.In this paper,key technologies of SBS are studied,including the beamforming algorithm,beam scanning scheme,and interference cancellation algorithm.To transmit and receive ISAC signals simultaneously,a double-coupling antenna array is applied.The free detection beam and directional communication beam are proposed for joint communication and sensing to meet the requirements of beamwidth and pointing directions.The joint timespace-frequency domain division multiple access algorithm is proposed to cancel the interference of SBS,including multiuser interference and duplex interference between sensing and communication.Finally,the sensing and communication performance of SBS under the industrial scientific medical power limitation is analyzed and simulated.Simulation results show that the communication rate of SBS can reach over 100 Mbps and the range of sensing and communication can reach about 500 m. 展开更多
关键词 BEAMFORMING integrated sensing and communication(ISAC) interference cancellation performance analysis sensing base station
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Schiff bases及配合物的研究进展 被引量:8
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作者 焦元红 张前 《黄石理工学院学报》 2007年第3期38-41,共4页
希夫碱配体及与后过渡金属元素所形成的配合物,以其多样的结构和广泛的用途愈来愈受到人们的重视。文章综述了Schiff base配体及配合物的发展状况以及在生物化学、催化化学、分析化学、材料化学等方面的研究与应用,并指出了它的美好前景。
关键词 SCHIFF base 配体 金属配合物
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B-Spline曲线聚风装置直线翼垂直轴风力机启动性能数值模拟 被引量:2
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作者 李岩 马云飞 +2 位作者 佟国强 杨胜兵 肖振军 《排灌机械工程学报》 CSCD 北大核心 2024年第3期265-272,共8页
为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进... 为了提升直线翼垂直轴风力机的启动性能,基于B-Spline曲线生成方法,提出一种具有流线型轮廓的聚风装置,将其分别安装在风轮顶端和底端,用以提升风轮附近的来流风速,使风轮汲取更多风能,达到更易启动的特点.选取聚风装置的5个结构参数进行设计:聚风装置与风轮间隙距离ΔL、底圆半径R_(1)、顶圆半径R_(2)、入口角度α_(1)和出口角度α_(2).设计方法采用二次旋转正交组合筛选最优模型,通过三维数值模拟研究聚风装置参数对直线翼垂直轴风力机启动性能的影响,获得了最佳外形参数组合.此外,对有无加装聚风装置的直线翼垂直轴风力机进行了静态三维数值模拟.结果表明,通过添加具有外凸流线型轮廓的聚风装置,直线翼垂直轴风力机的启动性能有显著提升.在风速较低的情况下,性能改善更加明显.聚风装置可使直线翼垂直轴风力机的平均启动力矩系数最大增加38.8%,峰值平均启动力矩系数最大可增加31.2%. 展开更多
关键词 垂直轴风力机 聚风装置 b-spline曲线 启动性能 数值模拟
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5-硝基水杨醛氨基酸Schiff-bases铜配合物与DNA相互作用的研究 被引量:5
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作者 冯莉 顾文 +5 位作者 马小芳 许光军 刘慧 阎世平 廖代正 程鹏 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第1期27-31,共5页
用电子光谱、荧光淬灭光谱和循环伏安的方法,研究了(苯丙氨酸缩5-硝基水杨醛)铜(1)和(组氨酸缩5-硝基水杨醛)铜(2)与 DNA 的作用.结果表明,配合物均以插入模式与 DNA 作用;配合物与 DNA 作用强弱为:配合物(2)>配合物(1).
关键词 氨基酸 SCHIFF碱 铜配合物 DNA
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脱氢枞胺水杨醛类席夫碱(Schiff Bases)对铜离子萃取性能的研究 被引量:4
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作者 姚绪杰 饶小平 +1 位作者 王宗德 宋湛谦 《江西农业大学学报》 CAS CSCD 北大核心 2007年第3期461-465,共5页
合成5种脱氢枞胺水杨醛类Schiff碱,对其萃取铜离子的影响因素进行研究,并与萃取剂N902对电镀废水中铜离子的萃取性能进行了比较。结果表明:萃取温度和萃取时间对铜离子萃取率的影响不明显,萃取温度在20~30℃、萃取时间为2 h就能达到萃... 合成5种脱氢枞胺水杨醛类Schiff碱,对其萃取铜离子的影响因素进行研究,并与萃取剂N902对电镀废水中铜离子的萃取性能进行了比较。结果表明:萃取温度和萃取时间对铜离子萃取率的影响不明显,萃取温度在20~30℃、萃取时间为2 h就能达到萃取平衡;大部分Schiff碱在低pH范围内对铜离子的萃取效果不理想,在高pH范围内有较好的萃取性能。DHAA 2,3,4-三羟基苯甲醛的萃取效果与N902相当。 展开更多
关键词 脱氢枞胺 SCHIFF碱 溶剂萃取 铜离子
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Spaces with σ-locally Countable Weak Bases
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作者 夏省祥 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期37-41,共5页
In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to A... In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to Alexandroff’s problems. 展开更多
关键词 msss_mapping sequence_covering mapping cs_network weak base
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Synthesis and Biological Activities of Some Mannich Bases of 5-(4-Hydroxyphenyl)-1,3,4-Oxadiazole-2-Thione
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作者 庞华 张君仁 +1 位作者 帅翔 王建河 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第2期54-55,共2页
以对羟基苯甲酸乙酯为原料,经肼解、环化合成5(4羟基苯基)1,3,4二唑2硫酮,继而经Mannich反应合成了四种新曼尼希碱,其结构经红外光谱、核磁共振和元素分析证实。初步抑菌活性试验表明,显示弱的抑菌活性。
关键词 1 3 4-Oxadiazole-2-thione Mannich bases Biological activities
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An Adaptive Median Filter Algorithm Based on B-spline Function 被引量:11
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作者 Mei-Sen Pan Jing-Tian Tang Xiao-Li Yang 《International Journal of Automation and computing》 EI 2011年第1期92-99,共8页
According to the B-spline convolution mask, first, the contrast sensitiveness (CS) is computed and then is viewed as a noise sensitiveness coeficient (NSC) to adaptively determine a noise-recognized threshold valu... According to the B-spline convolution mask, first, the contrast sensitiveness (CS) is computed and then is viewed as a noise sensitiveness coeficient (NSC) to adaptively determine a noise-recognized threshold value. Based on the noise density function (NDF) in a 3×3 window, the filtering window size is adaptively adjusted, and then a median filter is used to eliminate the noise-marked pixels. The experiment results show that the proposed algorithm can preserve image detail information well and effectively remove the noises, particularly the impulse noises that is also called salt-and-pepper noises superimposed on the computed tomography (CT) and magnetic resonance imaging (MRI) medical images. 展开更多
关键词 Salt-and-pepper noise median filter human vision system b-spline.
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Synthesis of New Schiff Bases Containing Thiophene Moiety 被引量:5
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作者 Zhu Wan-ren, Hu Pei-zhi, Li Mei-ying, Huang Xiao-ling, Wu Cheng-taiCollege of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072,Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第02A期433-436,共4页
Seven new Schiff bases, which are 4,4,4-trifluo-ro-1-(2-thienyl)-1-butanone-3-Z, Z =-thioseraicarbazone (a); -thiocarbohydrazone (b),-benzoic hydrazone (c), -( o-hydroxyphenyl) imine (d) ,-nicotinic hydrazone (e),-sal... Seven new Schiff bases, which are 4,4,4-trifluo-ro-1-(2-thienyl)-1-butanone-3-Z, Z =-thioseraicarbazone (a); -thiocarbohydrazone (b),-benzoic hydrazone (c), -( o-hydroxyphenyl) imine (d) ,-nicotinic hydrazone (e),-salicylic hydrazone (f), and -(p-fluoro-m-chlorophenyl) imine (g), have been synthesized by reaction of 4, 4, 4-trifluoro-1-(2-thienyl)-1,3-butanedione (TFTBD) with corresponding hy-drazides or anilines, acetic acid or p-toluence sulfonic acid as catalyst, and characterized by Elemental analysis, IR, UV-Vis,1H NMR and MS. The MS spectra confirmed that the -C3=O condensed with primary amino group. Tauto-merism of the compounds is discussed. 展开更多
关键词 thiophene moiety Schiff base synthsis tau-tomerism
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A B-Spline Based BEM and Its Applicaion in Predicting Wave Forces on 3D Bodies 被引量:8
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作者 滕斌 柏威 向阳 《China Ocean Engineering》 SCIE EI 1999年第3期257-264,共8页
For the computation of wave forces on structures, a B-spline expansion is applied to discretize the body surface, and represent the velocity potentials on the body surface. The expansion coefficients for the body geom... For the computation of wave forces on structures, a B-spline expansion is applied to discretize the body surface, and represent the velocity potentials on the body surface. The expansion coefficients for the body geometry are determined by the Least Square Method, and the coefficients for velocity potentials by the Galerkin method. The method can give continuous description of velocity potentials and their derivatives on the whole smooth body surface. The method has been implemented, and numerical results show that the method gives very accurate results and its convergence is fast. 展开更多
关键词 wave force boundary element method b-spline
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The Evolution of Regional Economic Resilience in the Old Industrial Bases in China: A Case Study of Liaoning Province, China 被引量:7
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作者 LI Liangang ZHANG Pingyu +2 位作者 LO Kevin LIU Wenxin LI Jing 《Chinese Geographical Science》 SCIE CSCD 2020年第2期340-351,共12页
The economic transformation of the old industrial bases is a key research topic among geographers in China.In this paper,we propose that the concept of regional economic resilience(RER)has unique theoretical value in ... The economic transformation of the old industrial bases is a key research topic among geographers in China.In this paper,we propose that the concept of regional economic resilience(RER)has unique theoretical value in analyzing the economic transformation of the old industrial bases.We constructed an analytical framework and an index system and applied the conceptual tools to study the evolution of RER in the old industrial base of Liaoning Province in China,which is currently subjected to not only sudden shocks but‘slow burn’—longer term processes of change that may nevertheless affect the regional economy.There are four main findings:first,the evolution of RER in Liaoning can be divided into four stages from 2000 to 2015.Liaoning is currently in its conservation-release period,and the next stage will be a release-reorganization period.Second,the RER of the majority of the studied cities is lower than the average value for Liaoning,and this is mainly attributed to the relatively weak vulnerability-resistance and adaptability-transformation capacity of these cities.Third,the RER levels of the 14 cities in Liaoning differ significantly.At the first level is Shenyang and Dalian,at the second level is Dandong and Yingkou,and the third level comprises the remaining cities.Fourth,regional economic resilience is mainly determined by vulnerability-resistance,which indirectly reflects Liaoning’s lack of adaptability-transformation capacity,and the ability of the region to renew or create a new development path is weak. 展开更多
关键词 regional economic resilience(RER) EVOLUTIONARY process old industrial bases LIAONING Province China
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Reaction of Nitrosonium (NO^+) with Schiff Bases 被引量:3
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作者 YuLuZHOU CongDeHUO ShuMIAO LongMinWU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期801-804,共4页
The reaction of nitrosonium (NO+) with Schiff bases produced diazonium salts and aldehydes in good yield. The reaction is assumed to be an electrophilic reaction of nitrosonium with imines via a four-member ring inter... The reaction of nitrosonium (NO+) with Schiff bases produced diazonium salts and aldehydes in good yield. The reaction is assumed to be an electrophilic reaction of nitrosonium with imines via a four-member ring intermediate. 展开更多
关键词 NITROSONIUM Schiff bases electrophilic.
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Dioxygen Affinity and Catalytic Performance of Bis-(furaldehyde) Schiff Bases Co(II) Complexes in Cyclohexene Oxidation 被引量:4
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作者 Sun, B Chen, JR +1 位作者 Hu, JY Li, XJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期1043-1046,共4页
Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of th... Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed. 展开更多
关键词 Schiff base cobalt (II) complex OXYGENATION catalytic oxidation CYCLOHEXENE
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Synthesis, Structural Features and Evaluation of Antibacterial Activities of Two Schiff Bases Derived from 3,4-Dihydroxybenzhydrazide 被引量:3
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作者 刁云鹏 钟民涛 +6 位作者 张厚利 黄珊珊 刘欣 李传勋 郑泽宝 林原 黄敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1684-1688,共5页
A new Schiff base compound (I), (E)-N'-(2-hydroxy-3-methoxybenzylidene)-3,4-dihydroxybenzohydrazide-ethanol-water (1/1/1), has been synthesized and characterized by elemental analysis, IR spectra, and single-... A new Schiff base compound (I), (E)-N'-(2-hydroxy-3-methoxybenzylidene)-3,4-dihydroxybenzohydrazide-ethanol-water (1/1/1), has been synthesized and characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 7.459(4), b = 18.316(10), c = 13.638(7), β = 101.585(9)o, V = 1825.2(17)3, Z = 4, μ = 0.104 mm-1, Dc = 1.333 g/cm3, F(000) = 776, the final R = 0.0635 and wR = 0.1302 for 3216 observed reflections with I 〉 2σ(I). Another compound (Ⅱ), (E)-N'-(2,5-dimethoxybenzylidene)-3,4-dihydroxybenzohydrazide-ethanol-water (1/1/1), has been synthesized and reported before. The antibacterial activities of these two compounds against seven bacteria were first evaluated, and one compound showed considerable antibacterial activity against S. aureus. 展开更多
关键词 Schiff base crystal structure ANTIBACTERIAL
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Geometry Modeling of Ship Hull Based on Non-uniform B-spline 被引量:4
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作者 王虎 邹早建 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第2期189-192,共4页
In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative m... In order to generate the three-dimensional (3-D) hull surface accurately and smoothly,a mixed method which is made up of non-uniform B-spline together with an iterative procedure was developed.By using the iterative method the data points on each section curve are calculated and the generalized waterlines and transverse section curves are determined.Then using the non-uniform B-spline expression,the control vertex net of the hull is calculated based on the generalized waterlines and section curves.A ship with tunnel stern was taken as test case.The numerical results prove that the proposed approach for geometry modeling of 3-D ship hull surface is accurate and effective. 展开更多
关键词 hull surface geometry modeling non-uniform b-spline iterative procedure
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2D numerical manifold method based on quartic uniform B-spline interpolation and its application in thin plate bending 被引量:6
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作者 温伟斌 蹇开林 骆少明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第8期1017-1030,共14页
A new numerical manifold (NMM) method is derived on the basis of quartic uniform B-spline interpolation. The analysis shows that the new interpolation function possesses higher-order continuity and polynomial consis... A new numerical manifold (NMM) method is derived on the basis of quartic uniform B-spline interpolation. The analysis shows that the new interpolation function possesses higher-order continuity and polynomial consistency compared with the conven- tional NMM. The stiffness matrix of the new element is well-conditioned. The proposed method is applied for the numerical example of thin plate bending. Based on the prin- ciple of minimum potential energy, the manifold matrices and equilibrium equation are deduced. Numerical results reveal that the NMM has high interpolation accuracy and rapid convergence for the global cover function and its higher-order partial derivatives. 展开更多
关键词 numerical manifold method (NMM) manifold element b-spline thinplate bending
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