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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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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-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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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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以各民族人口共同现代化助推边疆地区高质量发展——兼论边疆地区高质量发展的“四维评价体系”
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作者 段成荣 周思瑶 《云南师范大学学报(哲学社会科学版)》 北大核心 2026年第1期21-31,共11页
边疆地区高质量发展是中国式现代化的重要组成部分,其对推进共同富裕的空间收敛、提升国家安全韧性并畅通国内国际双循环具有重要意义。“十五五”时期高质量发展的要求,意味着发展理念从“有没有”转向“好不好”。在空间层面,由于不... 边疆地区高质量发展是中国式现代化的重要组成部分,其对推进共同富裕的空间收敛、提升国家安全韧性并畅通国内国际双循环具有重要意义。“十五五”时期高质量发展的要求,意味着发展理念从“有没有”转向“好不好”。在空间层面,由于不同地区在区位条件、资源禀赋、历史路径与生态承载方面存在结构性差别,“好”的内涵具有显著的异质性特征。边疆地区同时承担着多重功能,其“好”的内涵在于安全与开放、保护与开发、多元与统一的系统平衡。据此,本研究构建了以“稳不稳”与“绿不绿”为底线、以“融不融”为主线、以“通不通”为路径的四维评价体系。传统依赖规模扩张的经济发展路径在“有没有”阶段有现实合理性,但面对四重目标可能存在的内在张力时,该路径难以兼顾多元复合的治理需求,因此必须引入一个能够同时内嵌于安全屏障、生态建设与社会治理之中的核心变量。有鉴于此,本文提出“各民族人口共同现代化”作为统摄性抓手,围绕人口素质提升与经济社会参与方式转变,系统性推动上述各目标的协同实现。当前各民族人口现代化总体显著提升,但呈“协同推进、分化并存”的基本格局。特别是在高等教育与城镇化融入等关键维度上,族际差距呈现扩大趋势,反映出边疆地区各民族人口共同现代化仍面临现实挑战。为了破解相关挑战,当前亟须着力扩大边境地区少数民族高等教育规模与质量,推进以人为核心的新型城镇化,实现“边疆地区一个都不能少”的中国式现代化。 展开更多
关键词 高质量发展 各民族共同现代化 边疆发展 人口发展 四维评价体系
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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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页岩油水平井立体开发井组设计探索
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作者 窦玉玲 《钻探工程》 2026年第2期108-114,共7页
当前国内页岩油立体开发仍处于探索阶段,为构建钻井、压裂、投产一体化高效建产模式,需开展井组轨道设计与作业时序的协同优化。本文以济阳坳陷民丰洼陷某实际井台为研究载体,针对“纵向横推Tank”与“横向纵推Tank”2种运行模式,采用... 当前国内页岩油立体开发仍处于探索阶段,为构建钻井、压裂、投产一体化高效建产模式,需开展井组轨道设计与作业时序的协同优化。本文以济阳坳陷民丰洼陷某实际井台为研究载体,针对“纵向横推Tank”与“横向纵推Tank”2种运行模式,采用最近距离法结合Landmark软件,系统分析造斜点位置、造斜点相对深浅、入靶前造斜率对碰撞风险的影响,并提出针对性防碰措施。研究表明,“纵向横推”模式通过轨道平面错开设计,整体碰撞风险较低,适应性更强;而“横向纵推”模式因轨道交叉较多,防碰设计更为复杂,需依靠造斜点双重错开优化以降低风险。研究成果为页岩油立体开发井组设计提供了可行的技术支撑,为后续不同建产模式下的井组优化提供了经验借鉴。 展开更多
关键词 页岩油 大平台开发 立体井网 井组设计 Tank模式 轨道设计 防碰分析 民丰洼陷
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水凝胶在吸附方面的研究进展
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作者 元宁宁 《山西化工》 2026年第1期56-58,共3页
作为重要的吸附材料,水凝胶因其独特的三维网络结构、高含水量和丰富的官能团,解决了传统吸附剂如活性炭和生物质基材料等再生效率低、成本高以及对复杂水质的适应性不足等问题,并在废水处理、生物医学和环境修复等领域展现出广阔的应... 作为重要的吸附材料,水凝胶因其独特的三维网络结构、高含水量和丰富的官能团,解决了传统吸附剂如活性炭和生物质基材料等再生效率低、成本高以及对复杂水质的适应性不足等问题,并在废水处理、生物医学和环境修复等领域展现出广阔的应用前景。近年来,新型水凝胶吸附剂以其优异的吸附性能、环境友好性和可再生性备受关注。特别值得关注的是,通过结构设计与功能化改性,水凝胶不仅能够实现对重金属离子和染料分子的高效吸附,还兼具机械柔韧性和环境适应性,为拓展其在复杂环境中的应用提供了全新解决方案。研究介绍了基于水凝胶对重金属离子的吸附和对染料的吸附的相关研究成果,剖析了水凝胶的吸附作用在不同条件下的性能表现及作用机制,为研究者了解水凝胶在吸附方面的研究进展提供了理论指导。 展开更多
关键词 水凝胶 三维网络结构 高含水量 丰富官能团 吸附
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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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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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共同富裕背景下农村低收入群体多维识别与常态化帮扶的着力点分析 被引量:2
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作者 罗良清 黄斐 《农村经济》 北大核心 2025年第2期115-128,共14页
低收入人群是促进共同富裕的重点帮扶保障人群。本文采用中国家庭追踪调查(CFPS)2014-2020年四期数据,结合模糊集理论对“收入导向型”A-F方法在指标临界值确定和权重设置方面进行改进,构建农村低收入群体关注指数,对农村低收入群体进... 低收入人群是促进共同富裕的重点帮扶保障人群。本文采用中国家庭追踪调查(CFPS)2014-2020年四期数据,结合模糊集理论对“收入导向型”A-F方法在指标临界值确定和权重设置方面进行改进,构建农村低收入群体关注指数,对农村低收入群体进行多维静态识别和动态追踪。从分类帮扶的视角将农村低收入群体分为三个组别,借助多元离散选择面板数据(MLogit)模型分析影响农村低收入群体不同组别形成的驱动因素。研究发现:第一,农村低收入群体关注指数能够实现对农村低收入群体的有效识别和动态追踪。其中建档立卡户得益于精准扶贫政策,关注指数的平均隶属份额较非建档立卡户在时间维度上下降更明显。第二,通过对农村低收入群体进行动态追踪,发现低收入群体中存在持久性低收入人群。第三,根据分类框架,农村低收入群体可分为脆弱低收入组、促增收低收入组和入中潜力低收入组三个组别,且不同组别之间由于特征差异需要采取不同的分类帮扶政策。基于上述分析,本文建议从多维视角对农村低收入群体开展识别和监测,并建立农村低收入群体分级体系。同时拓宽农村低收入群体收入来源渠道,发挥互联网信息优势,帮助其获得更多发展机会。 展开更多
关键词 低收入群体 多维识别 模糊集理论 常态化帮扶
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基于感官导向的乌梅浸膏特色风味组群产品开发 被引量:2
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作者 张文娟 史清照 +7 位作者 崔凯 洪群业 洪广峰 徐秀娟 杨伟平 霍现宽 徐石磊 吴彦 《中国烟草学报》 北大核心 2025年第3期1-11,共11页
【目的】开发多元化的乌梅浸膏香料产品,提高产品功能聚焦度。【方法】利用多级膜分离和二维柱色谱对自主研发的乌梅浸膏进行精细分离,结合感官评价定位风格特征突出的乌梅特色风味组群,对获得的特色风味组群进行重组试验,利用热裂解-气... 【目的】开发多元化的乌梅浸膏香料产品,提高产品功能聚焦度。【方法】利用多级膜分离和二维柱色谱对自主研发的乌梅浸膏进行精细分离,结合感官评价定位风格特征突出的乌梅特色风味组群,对获得的特色风味组群进行重组试验,利用热裂解-气相/质谱(Py-GC/MS)模拟分析感官作用较好的重组产品在卷烟燃吸过程中的香气释放情况。【结果】(1)乌梅浸膏通过4级膜分离及二维柱色谱分离共获得了17个组群,感官评价显示50 nm膜截留组群、反渗透(RO)截留组群和柱色谱B1组群在提升卷烟烟气状态、舒适性和特征香韵方面整体作用效果较好,确定为乌梅特色风味组群。(2)通过调整3个特色风味组群的组合配比,可获得作用效果优于分离前乌梅浸膏的重组产品。(3)优选的重组产品热裂解产物中以酯类、杂环类及酚类化合物居多,主要表现为果香、甜香、烟熏香、焦甜香等香气类型;重组产品裂解产物中呈蜡脂气、烟熏香、酚类气息、焦甜香、烘焙香的成分占比明显少于分离前乌梅浸膏的,呈果香香气的裂解成分在重组产品中占比明显增加,该结果从物质基础层面较好地解释了优选重组产品增加卷烟果香香韵,减轻蜡质气、烟熏香等杂气的感官效果。【结论】通过感官导向的特色风味组群定位和重组,能够实现乌梅浸膏风味聚焦、产品多元的精细化加工需求。 展开更多
关键词 乌梅浸膏 特色风味组群 膜分离 二维柱色谱 重组 感官导向
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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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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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复合荷载作用下斜桩群桩响应简化计算方法
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作者 孔令刚 刘维 +2 位作者 夏海波 郑振华 陈云敏 《中南大学学报(自然科学版)》 北大核心 2025年第5期1900-1910,共11页
基于半无限弹性地基假设建立适于快速计算推、压、弯、扭等荷载联合作用大型斜桩群桩响应的简化分析模型,分析三维空间中任意倾斜方向和角度的两相邻斜桩间不同种类桩-土-桩相互作用影响。首先,将两斜桩中多种类型的桩头变形间相互作用... 基于半无限弹性地基假设建立适于快速计算推、压、弯、扭等荷载联合作用大型斜桩群桩响应的简化分析模型,分析三维空间中任意倾斜方向和角度的两相邻斜桩间不同种类桩-土-桩相互作用影响。首先,将两斜桩中多种类型的桩头变形间相互作用简化为桩头轴向、侧向位移和扭转角,分析其对邻桩三类桩头变形量的影响;然后,引入自由场地位移衰减系数,量化分析土面上竖向、水平和扭转3种位移随水平距离的变化规律;最后,基于虚拟桩假设和坐标变换,推导出计算三维空间中任意倾斜方向和角度的两桩间相互作用的矩阵表达式,基于该分析模型开发了群桩分析程序PIGEAN。研究结果表明:斜桩桩头的轴向、侧向和扭转响应可近似采用相应荷载下的直桩解析解或近似解计算。3组不同荷载组合的多组斜桩群桩模型试验结果证明了斜桩的桩-土-桩相互作用三维分析方法能有效计算斜桩间相互作用的影响,提高计算准确性;证明了本模型在计算复合荷载下大规模群桩的高效性。 展开更多
关键词 斜桩 桩-土-桩相互作用 群桩 荷载组合 三维空间
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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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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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快堆多群截面处理程序MGGC2.0的验证与确认
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作者 马续波 马隆霄 +2 位作者 马旭东 张腾 陈相 《强激光与粒子束》 北大核心 2025年第7期133-140,共8页
基于多群截面的确定论计算方法一直都是反应堆工程设计的重要方法,多群截面精度直接影响着反应堆物理计算的精度。为了产生快堆高精度的截面数据,华北电力大学开发了高精度截面处理程序MGGC2.0,对该程序进行了基准验证和确认。基于ENDF... 基于多群截面的确定论计算方法一直都是反应堆工程设计的重要方法,多群截面精度直接影响着反应堆物理计算的精度。为了产生快堆高精度的截面数据,华北电力大学开发了高精度截面处理程序MGGC2.0,对该程序进行了基准验证和确认。基于ENDF/B-Ⅶ.1库计算无限大均匀混合介质UO_(2)、MOX、U-TRUZr燃料,将MGGC2.0与MCNP产生的宏观截面对比验证,验证了程序产生多群截面的精度,超细群宏观多群总截面与MCNP的参考解的相对偏差基本在5%以内。然后对俄罗斯快堆实验BFS97-1进行了计算,提出了针对多种燃料排布形式的燃料少群截面均匀化方法,利用MGGC2.0的碰撞概率法计算了燃料的少群截面数据,利用DIF3D程序进行堆芯计算,同时还对比了不同截面均匀化方法的结果。研究结果表明:对于BFS97-1,如果直接采用临界搜索产生的截面,DIF3D计算的有效增殖因数(k_(eff))结果与MCNP计算的k_(eff)的绝对偏差为2.541×10^(−2),通过改进燃料轴向不均匀计算方法,使得偏差降到了5.0×10^(−4)以下。针对BFS97-1、BFS97-2、BFS97-5和BFS97-6的计算结果与MCNP结果的偏差都在3.0×10^(−3)以内,验证了程序产生多群和少群截面具有较高精度,可以满足工程设计要求。 展开更多
关键词 多群截面 MGGC2.0 一维均匀化方法 BFS实验基准题 快堆
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