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ON THE CLASSIFICATION OF AF-ALGEBRAS AND THEIR DIMENSION GROUPS(Ⅱ)
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作者 HUANG ZHAOBO(InStitute of Mathematics, Fudan Universityt Shanghai 200433, China.) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第3期391-398,共8页
This paper is a continuation of [1]. It gives some applications of the results in [1], containing some examples of pure-infinite AF-algebras and the invariant properties of the types of the C-extensions by two AF-alge... This paper is a continuation of [1]. It gives some applications of the results in [1], containing some examples of pure-infinite AF-algebras and the invariant properties of the types of the C-extensions by two AF-algebras of the same type. 展开更多
关键词 AF-algebra dimension group C-extension.
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Flag-transitive point-primitive 2-(v,k,4) symmetric designs and two dimensional classical groups 被引量:5
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作者 ZHOU Sheng-lin TIAN De-lu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期334-341,共8页
Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and ... Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and Xx = PGL2(3) where x is a point of D. 展开更多
关键词 Symmetric design FLAG-TRANSITIVE point-primitive two dimensional classical group.
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THE JUMPING PHENOMENON OF THE DIMENSIONS OF COHOMOLOGY GROUPS OF TANGENT SHEAF 被引量:2
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作者 叶轩明 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1746-1758,共13页
Let X be a compact complex manifold. Consider a small deformation π : X → B of X, the dimensions of the cohomology groups of tangent sheaf Hq(xt, Txt ) may vary under this deformation. This article studies such p... Let X be a compact complex manifold. Consider a small deformation π : X → B of X, the dimensions of the cohomology groups of tangent sheaf Hq(xt, Txt ) may vary under this deformation. This article studies such phenomena by studying the obstructions to deform a class in Hq(X, 5TX) with parameter t and gets a formula for the obstructions. 展开更多
关键词 dimensions of cohomology groups of tangent sheaf deformation OBSTRUCTION Kodaira-Spencer class
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Three-dimensional visualization of the functional fascicular groups of a long-segment peripheral nerve 被引量:3
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作者 Jian Qi Wei-Ya Wang +7 位作者 Ying-Chun Zhong Jia-Ming Zhou Peng Luo Ping Tang Cai-Feng He Shuang Zhu Xiao-Lin Liu Yi Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1465-1470,共6页
The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair ... The three-dimensional(3D) visualization of the functional bundles in the peripheral nerve provides direct and detailed intraneural spatial information. It is useful for selecting suitable surgical methods to repair nerve defects and in optimizing the construction of tissue-engineered nerve grafts. However, there remain major technical hurdles in obtaining, registering and interpreting 2D images, as well as in establishing 3D models. Moreover, the 3D models are plagued by poor accuracy and lack of detail and cannot completely reflect the stereoscopic microstructure inside the nerve. To explore and help resolve these key technical problems of 3D reconstruction, in the present study, we designed a novel method based on re-imaging techniques and computer image layer processing technology. A 20-cm ulnar nerve segment from the upper arm of a fresh adult cadaver was used for acetylcholinesterase(ACh E) staining. Then, 2D panoramic images were obtained before and after ACh E staining under the stereomicroscope. Using layer processing techniques in Photoshop, a space transformation method was used to fulfill automatic registration. The contours were outlined, and the 3D rendering of functional fascicular groups in the long-segment ulnar nerve was performed with Amira 4.1 software. The re-imaging technique based on layer processing in Photoshop produced an image that was detailed and accurate. The merging of images was accurate, and the whole procedure was simple and fast. The least square support vector machine was accurate, with an error rate of only 8.25%. The 3D reconstruction directly revealed changes in the fusion of different nerve functional fascicular groups. In conclusion. The technique is fast with satisfactory visual reconstruction. 展开更多
关键词 nerve regeneration peripheral nerve ulnar nerve three-dimensional reconstruction functional fascicular group REGISTRATION segmentation locating spots auto-registration ACETYLCHOLINESTERASE neural regeneration
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New three-dimensional guidance law for BTT missiles based on differential geometry and Lie-group 被引量:2
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作者 Shuangchun Peng Liang Pan Tianjiang Hu Lincheng Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期684-690,共7页
A new non-decoupling three-dimensional guidance law is proposed for bank-to-turn (BTT) missiles with the motion coupling problem. In this method, the different geometry is taken for theoretically modeling on B-IT mi... A new non-decoupling three-dimensional guidance law is proposed for bank-to-turn (BTT) missiles with the motion coupling problem. In this method, the different geometry is taken for theoretically modeling on B-IT missiles' motion within the threedimensional style without information loss, and meanwhile, Liegroup is utilized to describe the line-of-sight (LOS) azimuth when the terminal angular constraints are considered. Under these cir- cumstances, a guidance kinematics model is established based on differential geometry. Then, corresponding to no terminal angular constraint and terminal angular constraints, guidance laws are re- spectively designed by using proportional control and generalized proportional-derivative (PD) control in SO(3) group. Eventually, simulation results validate that this developed method can effectively avoid the complexity of pure Lie-group method and the information loss of the traditional decoupling method as well. 展开更多
关键词 three-dimensional guidance law differential geometry Lie-group control bank-to-turn (BTT).
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Plane Elasticity and Dislocation of One-Dimensional Hexagonal Quasicrystals with Point Group 6 被引量:1
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作者 刘官厅 郭瑞平 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期87-91,共5页
Plane elasticity theory of one-dimensional hexagonal quasicrystals with point group 6 is proposed and established. As an application of this theory, one typical example of dislocation problem in the quasicrystals is i... Plane elasticity theory of one-dimensional hexagonal quasicrystals with point group 6 is proposed and established. As an application of this theory, one typical example of dislocation problem in the quasicrystals is investigated and its exact analytic solution is presented. The result obtained indicates that the stress components of (elastic) fields of a straight dislocation in the quasicrystals still first order singularity, which is the same as the (general crystals,) but are related with the Burgers vector of phason fields, which is different from the general (crystals.) 展开更多
关键词 one-dimensional hexagonal quasicrystals plane elasticity DISLOCATION point group 6
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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 Three-dimensionally ordered macroporous polymer FUNCTIONALIZATION Hydrophilic space arm Heterocyclic functional group
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Alternating Group Explicit Iterative Methods for One-Dimensional Advection-Diffusion Equation
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作者 Ning Chen Haiming Gu 《American Journal of Computational Mathematics》 2015年第3期274-282,共9页
The finite difference method such as alternating group iterative methods is useful in numerical method for evolutionary equations and this is the standard approach taken in this paper. Alternating group explicit (AGE)... The finite difference method such as alternating group iterative methods is useful in numerical method for evolutionary equations and this is the standard approach taken in this paper. Alternating group explicit (AGE) iterative methods for one-dimensional convection diffusion equations problems are given. The stability and convergence are analyzed by the linear method. Numerical results of the model problem are taken. Known test problems have been studied to demonstrate the accuracy of the method. Numerical results show that the behavior of the method with emphasis on treatment of boundary conditions is valuable. 展开更多
关键词 ONE-dimensionAL ADVECTION-DIFFUSION Equations ALTERNATING group EXPLICIT ITERATIVE Methods Stability Convergence Finite Difference Method
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Finding Main Causes of Elevator Accidents via Multi-Dimensional Association Rule in Edge Computing Environment 被引量:2
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作者 Hongman Wang Mengqi Zeng +1 位作者 Zijie Xiong Fangchun Yang 《China Communications》 SCIE CSCD 2017年第11期39-47,共9页
In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and impl... In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and implementing a method by combining classical Apriori algorithm with the model, digging out frequent items of elevator accident data to explore the main reasons for the occurrence of elevator accidents. In addition, a collaborative edge model of elevator accidents is set to achieve data sharing, making it possible to check the detail of each cause to confirm the causes of elevator accidents. Lastly the association rules are applied to find the law of elevator Accidents. 展开更多
关键词 elevator group accidents APRIORI multi-dimensional association rules data cube edge computing
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The Unitary Group in Its Strong Topology
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作者 Martin Schottenloher 《Advances in Pure Mathematics》 2018年第5期508-515,共8页
The goal of this paper is to confirm that the unitary group U(H) on an infinite dimensional complex Hilbert space is a topological group in its strong topology, and to emphasize the importance of this property for app... The goal of this paper is to confirm that the unitary group U(H) on an infinite dimensional complex Hilbert space is a topological group in its strong topology, and to emphasize the importance of this property for applications in topology. In addition, it is shown that U(H) in its strong topology is metrizable and contractible if H is separable. As an application Hilbert bundles are classified by homotopy. 展开更多
关键词 UNITARY OPERATOR Strong OPERATOR Topology Topological group Infinite dimensional LIE group CONTRACTIBILITY Hilbert BUNDLE Classifying Space
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First-principles investigation of chemical modification on two-dimensional iron-phthalocyanine sheet
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作者 王洪博 苏燕 陈刚 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期475-479,共5页
Successful synthesis of single iron-phthalocyanie (FePc) framework layer on substrate and its transferrable properties open the door for decorating the separately distributed transition metals for exploring the dive... Successful synthesis of single iron-phthalocyanie (FePc) framework layer on substrate and its transferrable properties open the door for decorating the separately distributed transition metals for exploring the diverse properties. We have studied the effects of chemical modification on two-dimensional FePc organometallic framework with density functional theory. For simplicity, the non-metal atoms with variant valence electrons are used as prototypes to estimate the effects &ore chemical modifications with different functional groups. The thermo-stabilities of the non-metal atom decorated complex sheet materials have been estimated by the first-principles constant energy molecular dynamic simulations. Upon the non- metal atom adsorption, the magnetic moment could be changed from 2 ~tB to 0, 1, 2, and 3 ~tB per unit cell for the case of tetra-, penta-, hexa-, and hepta-valent non-metal modifications, respectively, showing interesting promise to tailor its magnetic properties for potential applications. 展开更多
关键词 first-principles calculation novel two-dimensional nanostructure functional group decoration
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基于Adaptive Group LASSO的CVaR高维组合投资模型
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作者 张杰 《中南财经政法大学研究生学报》 2018年第1期50-57,共8页
传统的CVaR条件风险价值组合投资模型能够很好的度量市场风险,但是容易在决策的过程中产生极端的投资权重,对CVaR模型增加一般范数约束后可以解决极端投资权重的问题,但却忽略了金融市场上常见的板块联动效应。基于上述原因,文章在... 传统的CVaR条件风险价值组合投资模型能够很好的度量市场风险,但是容易在决策的过程中产生极端的投资权重,对CVaR模型增加一般范数约束后可以解决极端投资权重的问题,但却忽略了金融市场上常见的板块联动效应。基于上述原因,文章在传统的CVaR模型的基础上,施加Adaptive Group LASSO惩罚,构建了一种基于Adaptive Group LASSO的CVaR高维组合投资模型,通过Adaptive Group LASSO分位数回归求解算法,实现了在消除极端投资头寸的同时达到金融资产组水平上变量稀疏化的目的。最后,蒙特卡洛模拟与实证研究均发现,与传统的CVaR组合投资模型以及带有LAS—SO约束的CVaR组合投资模型相比,基于Adaptive Group LASSO的CVaR模型能够更好的考虑板块联动效应,并在行业组水平上选择相应的金融资产。 展开更多
关键词 CVAR ADAPTIVE group LASSO 高维组合投资 组稀疏性 分位数回归
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A Framework for Exploring the Dynamics of Autonomous Work Groups in Manufacturing Organizations
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作者 Joseph W K Chan W B Lee 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期211-212,共2页
Nowadays, new paradigm of enterprise organization i s constantly changing due to the emergence of the global marketplace, the rise of information technology, and the emphasis of the social developments. This re quires... Nowadays, new paradigm of enterprise organization i s constantly changing due to the emergence of the global marketplace, the rise of information technology, and the emphasis of the social developments. This re quires a more flexible form of organization that are more adaptable to rapid cha nges in business environment such as autonomous work groups (AWGs) in order to achieve higher productivity and effectiveness. AWGs are work units responsib le for the production of goods and the provision of services. They involve team members in making decisions that are traditionally the responsibility of the sup ervisors and managers (Cohen & Bailey, 1997). Team members of AWGs are allowed t o self-regulate their behavior on jobs such as task assignments, methods for ca rrying out the work, and scheduling of activities etc. (Cohen & Ledford, 1994). For example, Motorola achieved a high organizational performance due to the succ essful implementation of AWGs in quality management (Piczak & Hauser, 1996). Xer ox also reported their operational successes based on the team-oriented work gr oups (Wageman, 1997). In recent years many organizations have replaced the traditional layers of manag ement with autonomous team-based work arrangements. Surveys indicated that the adoption of AWGs has soared in responding to the competitive business challenges . Many enterprises are making a deliberate effort to use AWGs to carry out work and operational processes as an alternative for hierarchical approaches (Lawler et al., 1995). There is a growing body of evidence that AWGs are more effective than traditionally managed groups and they contributes to organizational perform ance, such as improvement in operational performance, productivity, quality, cos t savings, employee attitude and behavior, and employee satisfaction (e.g. Pears on, 1992; Cohen & Ledford, 1994; Seers et al. 1995). Given the complexity and cognitive nature of team-based organizations, the mech anisms that the enterprises use in the development of the increasingly sophistic ated models, which can contribute to the effective functioning of AWGs, are extr emely important. The process of developing effective AWGs enables enterprises to inherent built-in intelligence of the organizations so that they will be more able to accommodate to external pressures and changes. The context of this paper is the construction of a dynamics framework and a stra tegic path for autonomous work groups in the technology-oriented manufacturing organization re-design. The framework is a conceptual one drawn from the litera ture survey. The importance of studying autonomous work groups for today’s manuf acturing organizations is claimed. Based on the General System Theory (GST), the characterization of AWGs is addressed. Three-dimensional domains such as t echnical content, service content, and relationship content are identified. A st rategic path is proposed to guide the organizations how the development of AWGs progresses at different levels of maturity that are associated with organization al effectiveness and performance. The utility of the model for AWGs is expected to provide technology-oriented organizations with a strategic path to achieve h igher organizational performance. 展开更多
关键词 autonomous work group three-dimensional dynamic s model general systems theory EFFECTIVENESS maturity level
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Symmetry analysis and explicit solutions of the (3+1)-dimensional baroclinic potential vorticity equation 被引量:1
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作者 胡晓瑞 陈勇 黄菲 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期35-45,共11页
This paper investigates an important high-dimensional model in the atmospheric and oceanic dynamics-(3+1)- dimensional nonlinear baroclinic potential vorticity equation by the classical Lie group method. Its symmet... This paper investigates an important high-dimensional model in the atmospheric and oceanic dynamics-(3+1)- dimensional nonlinear baroclinic potential vorticity equation by the classical Lie group method. Its symmetry algebra, symmetry group and group-invariant solutions are analysed. Otherwise, some exact explicit solutions are obtained from the corresponding (2+1)-dimensional equation, the inviscid barotropic nondivergent vorticy equation. To show the properties and characters of these solutions, some plots as well as their possible physical meanings of the atmospheric circulation are given out. 展开更多
关键词 (3+1)-dimensional nonlinear baroclinic potential vorticity equation symmetry group group-invariant solution explicit solution
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智能时代职业教育专业群立体化建设:现实困境与路径优化
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作者 王娟 《苏州市职业大学学报》 2024年第1期21-27,共7页
进入信息时代,大数据、人工智能等技术的快速发展助力职业教育专业群实现了立体化创新改革。在改革建设过程中,职业院校严格秉持多维价值内核的同时,还需要打造符合时代发展潮流的应用模式,为职业教育专业群立体化建设夯实发展基础。然... 进入信息时代,大数据、人工智能等技术的快速发展助力职业教育专业群实现了立体化创新改革。在改革建设过程中,职业院校严格秉持多维价值内核的同时,还需要打造符合时代发展潮流的应用模式,为职业教育专业群立体化建设夯实发展基础。然而,要实现智能时代职业教育专业群立体化建设,仍旧面临发展目标笼统、建设方案错位、管理标准缺失等问题。为此,可通过明晰专业群建设原则、完善专业群建设方针、设立专业群动态化管理标准等措施,寻求优化路径。 展开更多
关键词 智能时代 职业教育 专业群 立体化建设
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Three-Dimensional Shear Wave Velocity Structure of the Northeastern Brazilian Lithosphere
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作者 Jorge Luis de Souza Newton Pereira dos Santos Carlos da Silva Vilar 《International Journal of Geosciences》 2016年第6期849-872,共24页
A large number of Rayleigh wave dispersion curves recorded at twenty three seismic stations was used to investigate the 3-D shear wave velocity structure of the northeastern Brazilian lithosphere. A simple procedure t... A large number of Rayleigh wave dispersion curves recorded at twenty three seismic stations was used to investigate the 3-D shear wave velocity structure of the northeastern Brazilian lithosphere. A simple procedure to generate a three-dimensional image of Mohorovicic;discontinuity was applied in northeastern Brazil and the Moho 3-D image was in agreement with several isolated crustal thicknesses obtained with different geophysical methods. A detailed 3-D S wave velocity model is proposed for the region. In the crust, our model is more realist than CRUST2.0 global model, because it shows more details either laterally or in depth than global model, i.e., clear lateral variation and gradual increase of S wave velocity in depth. Down to 100 km depth, the 3-D S wave velocity model in northeastern Brazil is dominated by low velocities and this is consistent either with heat flow measurements or with measurements of the flexural strength of the lithosphere developed in the South American continent. Our 3-D S wave velocity model was also used to obtain the lithosphere thickness in each cell of the northeastern Brazil and the results were consistent with global studies about the Lithosphere-Asthenosphere Boundary worldwide. 展开更多
关键词 Rayleigh Waves group-Velocity Tomography Three-dimensional Shear Wave Velocity LITHOSPHERE Spatial Resolution Northeastern Brazil
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基于修正非线性薛定谔方程的三维聚焦波组波谱演化
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作者 吴良夫 卢文月 +2 位作者 张建宏 李欣 郭孝先 《船舶工程》 CSCD 北大核心 2024年第9期160-167,共8页
为了研究深水三维聚焦波的定向演化,对4阶修正非线性薛定谔方程(MNLSE)、3阶非线性项薛定谔方程(NLSE)以及线性方程等3种演化模型进行数值求解,并对生成的波谱特征以及其演化过程中的能量转移、波陡变化、平均波数变化以及带宽变化等特... 为了研究深水三维聚焦波的定向演化,对4阶修正非线性薛定谔方程(MNLSE)、3阶非线性项薛定谔方程(NLSE)以及线性方程等3种演化模型进行数值求解,并对生成的波谱特征以及其演化过程中的能量转移、波陡变化、平均波数变化以及带宽变化等特征进行对比研究。研究结果表明:在2种非线性演化模型的演化过程中均存在能量向高波数和低波数的转移,导致波浪波形发生变化,且非线性还会影响聚焦波陡、聚焦波组达到聚焦所需时间以及带宽等参数的变化;上述特征在2种非线性演化模型中存在着显著差异,4阶MNLSE演化下的三维聚焦波组特征优于3阶NLSE的演化。 展开更多
关键词 非线性薛定谔方程 三维聚焦波组 波谱演化 能量转移
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VI族元素修饰对二维AlN电子性质影响的第一性原理研究
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作者 莫秋燕 欧满琳 +2 位作者 张颂 荆涛 吴家隐 《人工晶体学报》 CAS 北大核心 2024年第9期1620-1628,共9页
采用密度泛函理论的第一性原理计算方法,研究了VI族元素(O、S、Se、Te)修饰对二维AlN电子性质的影响。计算结果表明,O修饰后,二维AlN体系的能带发生劈裂,从而转变为磁性材料;S、Se和Te修饰后,二维AlN电子态密度曲线自旋向上和自旋向下... 采用密度泛函理论的第一性原理计算方法,研究了VI族元素(O、S、Se、Te)修饰对二维AlN电子性质的影响。计算结果表明,O修饰后,二维AlN体系的能带发生劈裂,从而转变为磁性材料;S、Se和Te修饰后,二维AlN电子态密度曲线自旋向上和自旋向下完全对称,形成了非磁性结构。从态密度图可以看出,费米能级附近的态密度主要由修饰原子的p态电子和N原子的p态电子贡献,导带底部逐渐向低能区移动,导致二维AlN的吸收波长阈值从紫外线区域向可见光移动。因此,修饰的二维AlN光催化效率提高,并有应用于可见光响应的光电子和自旋电子器件的可能。 展开更多
关键词 二维AlN VI族元素 修饰 第一性原理 电子结构 磁性
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加权区间值犹豫模糊集的群决策方法
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作者 朱国成 张娟 赵瑞华 《喀什大学学报》 2024年第3期1-11,共11页
为了在区间值犹豫模糊集(IVHFS)中体现出决策专家的重要性,把所有评审专家的综合权重注入IVHFS中,进而定义了加权区间值犹豫模糊集(WIVHFS).将WIVHFS用三维点坐标(由区间值隶属度的中位数、区间值隶属度的清晰度以及评审专家综合权重构... 为了在区间值犹豫模糊集(IVHFS)中体现出决策专家的重要性,把所有评审专家的综合权重注入IVHFS中,进而定义了加权区间值犹豫模糊集(WIVHFS).将WIVHFS用三维点坐标(由区间值隶属度的中位数、区间值隶属度的清晰度以及评审专家综合权重构成)进行刻画,在此基础上给出了加权区间值犹豫模糊元(WIVHFE)的相关运算;基于WIVHFE的相关运算采用熵值法计算测评准则客观权重,利用0-1优先关系矩阵来获取任意2个备选方案的总测评准则权重优势值与总测评准则权重劣势值,并依据二者之间的大小排序方案.最后,通过一个具体案例说明了文中理论与方法的可行性. 展开更多
关键词 加权区间值犹豫模糊集 加权区间值犹豫模糊元 群决策方法 三维点坐标 0-1优先关系矩阵
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水平循环荷载作用下群桩基础累积变形三维数值模拟
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作者 王多银 李国洋 +4 位作者 王丽 段伦良 唐选海 吴穗庆 杜文力 《水运工程》 2024年第9期48-56,共9页
为进一步研究群桩基础水平累积变形特性,以及桩体自身因素、荷载因素、桩周土体因素等影响下的变化规律,结合USDFLD子程序的实现过程与ABAQUS三维建模过程,采用有限元计算结果对群桩累积变形特性进行研究。通过改变桩距、桩数、荷载入... 为进一步研究群桩基础水平累积变形特性,以及桩体自身因素、荷载因素、桩周土体因素等影响下的变化规律,结合USDFLD子程序的实现过程与ABAQUS三维建模过程,采用有限元计算结果对群桩累积变形特性进行研究。通过改变桩距、桩数、荷载入射角度、加载频率、土体初始弹性模量、桩-土界面摩擦系数等参数,进一步对群桩水平累积变形特性,及其在桩体自身因素、荷载因素、桩周土体因素等影响下的变化规律进行研究。数值模拟中经常忽略桩周土体弱化对群桩基础累积变形特性的影响,因此对如何在数值模型中实现土体软化也进行了研究。最终得到群桩水平累积变形特性,以及在各种影响因素下的变化规律,如在桩体自身因素的影响下,群桩承台水平累积变形随桩距与桩数的增加不断减小,荷载-位移滞回圈随桩数的减少越饱满,土体非线性越明显等变化规律。 展开更多
关键词 群桩基础 水平循环荷载 累积变形 三维数值
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