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基于共轭几何变换程序的国债市场利率期限结构波动建模 被引量:1
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作者 吴泽福 《运筹与管理》 CSSCI CSCD 北大核心 2013年第3期179-184,共6页
本文变革已有的利率期限结构模型估计依赖于定价误差平方和最小化原则,引入几何双重变换程序解决非线性约束的误差绝对距离最小化问题,丰富国债市场利率波动和定价研究的理论体系和研究方法;运用负指数平滑立方L1样条优化模型,克服B样... 本文变革已有的利率期限结构模型估计依赖于定价误差平方和最小化原则,引入几何双重变换程序解决非线性约束的误差绝对距离最小化问题,丰富国债市场利率波动和定价研究的理论体系和研究方法;运用负指数平滑立方L1样条优化模型,克服B样条函数对节点数目与定位的过度敏感和放宽对贴现函数的二阶导数平滑要求,协同拟合误差绝对距离与贴现函数波动率最小化,保留B样条函数刻画中长期利率波动趋势的优势,增强对短期利率波动结构突变的估计、定价和预测能力,缓解B样条和NSS模型在利率期限结构拟合存在的过度波动问题。 展开更多
关键词 国债市场 利率期限结构 几何变换程序 波动
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A Precise Information Extraction Algorithm for Lane Lines 被引量:3
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作者 Jinyan Chen Yaduan Ruan Qimei Chen 《China Communications》 SCIE CSCD 2018年第10期210-219,共10页
Lane line detection is a fundamental step in applications like autonomous driving and intelligent traffic monitoring. Emerging applications today have higher requirements for accurate lane detection. In this paper, we... Lane line detection is a fundamental step in applications like autonomous driving and intelligent traffic monitoring. Emerging applications today have higher requirements for accurate lane detection. In this paper, we present a precise information extraction algorithm for lane lines. Specifically, with Gaussian Mixture Model(GMM), we solved the issue of lane line occlusion in multi-lane scenes. Then, Progressive Probabilistic Hough Transform(PPHT) was used for line segments detection. After K-Means clustering for line segments classification, we solved the problem of extracting precise information that includes left and right edges as well as endpoints of each lane line based on geometric characteristics. Finally, we fitted these solid and dashed lane lines respectively. Experimental results indicate that the proposed method performs better than the other methods in both single-lane and multi-lane scenarios. 展开更多
关键词 multi-lane scenes lane line occlusion left and right edges endpoints of lane lines
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Development of 2D computer program to determine geometry of rock mass blocks 被引量:1
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作者 Yarahmadi Reza Bagherpour Raheb +2 位作者 Kakaie Reza Mirzaie N. Hossein Yari Mojtaba 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期191-194,共4页
Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understand- ing of t... Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understand- ing of these blocks geometry is an essential issue concerned in different domains of rock engineering such as support system of underground spaces built in jointed rock masses, design of blasting pattern, optimi- zation of fragmentation, determination of cube blocks in quarry mines, blocks stability, etc. The aim of this paper is to develop a computer program to determine geometry of rock mass blocks in two dimen- sional spaces. In this article, the eometrv of iointed rock mass is programmed in MATLABTM. 展开更多
关键词 Block detection Computer programming Rock mass Algorithm
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避开节点编号的陷阱
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作者 胡志昆 《林业建设》 2000年第5期32-33,共2页
简述了用有限元法分析杆系结构内力时描述杆几何特性的程序 ,对此程序运行出错原因进行分析 。
关键词 有限元法 节点编号 校准参数 杆件几何特性程序 程序运行出错 原因分析 纠正措施
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Self-organization of Atoms into Nanosystems
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作者 Titorov Dmitriy 《Journal of Chemistry and Chemical Engineering》 2012年第9期809-813,共5页
The mechanism of addition of separate atoms to a growing center is considered with application of model of a pair interpenetration of atoms. Features of geometrical model are related with the electronic structure of a... The mechanism of addition of separate atoms to a growing center is considered with application of model of a pair interpenetration of atoms. Features of geometrical model are related with the electronic structure of atoms and the Pauli's exclusion principle. The forces providing self-organization of atoms in the bulk of a condensed substance are shown. The calculated interatomic distances in graphite and alloys of gold with silver coincide with those known from experiments with accuracy of 0.1%. 展开更多
关键词 Pair interpenetration Pauli's exclusion principle interatomic forces SELF-ORGANIZATION interatomic distances graphite AuAg alloys.
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Applications of Power Rail Track Program to Tracings of Brazilian Railways
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作者 Sonia Janneth Rosero Munoz Mhileizer Arielys Toledo Arenas +1 位作者 Diogenes Cortijo Cost Cassio EduardoLima de Paiva 《Journal of Civil Engineering and Architecture》 2016年第4期501-512,共12页
In Brazil, the use of software and applications in railway geometric designs is rare. Currently, after the division and privatization of the national rail network, the concessionaires who assumed the administration, a... In Brazil, the use of software and applications in railway geometric designs is rare. Currently, after the division and privatization of the national rail network, the concessionaires who assumed the administration, are investing in modernization, recovery and extension of this transport model to make it more efficient. The PIL (Program of Investment in Logistics) has generated growth of the sector in response to the amount of investments, greatly enhancing the load capacity and optimizing the geometric design, which would allow speed of 80 km/h. Based on this information, the objective of this research is to verify the software applications of Power Rail Track Program of Bentley Systems, Inc. for geometric designs in future deployments of railways in Brazil. This software is based on numerical calculations, including roller adjustment by the least squares method to calculate and choose the best alignments, and regression tools, to a fast and effectively optimization of various parameters of the geometry for a future or existing railway. Different variables that allow you to optimize the geometric design are analyzed, considering several optional alignments and complex restrictions present in geometric design, taking into account variables such as circular curves, transition, tangents and rays. The software regression tools include curvature diagrams identifying points and curves, tangent and spirals. The analysis results are presented quickly and points can be added or deleted from the regression analysis, providing improved tracing. The software also allows to detail the elements of the executive project of the railway line such as rails, joints, turning points, waypoints and others. The result of this study has shown that the application of the Power Rail Track Program generates significant cost savings in time and increases in productivity, providing greater opportunity to optimize the geometry and reducing geometric design costs. 展开更多
关键词 Geometric design railways optimization software geometric tracing.
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Fractal Geometry of a Dendrogram
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作者 Francisco Casanova-del-Angel 《Journal of Mathematics and System Science》 2014年第1期14-18,共5页
The fractal structure shown by the poligonal created by unions of middle points of vertices, nodes or peaks of dendograms terminal classes is presented. Its generating fractal, the details of its construction, and the... The fractal structure shown by the poligonal created by unions of middle points of vertices, nodes or peaks of dendograms terminal classes is presented. Its generating fractal, the details of its construction, and the way to measure its segments are defined; its property of inverted scale, the type of meshing, its property of axial symmetry and a theorem on transformation of linear affinity are considered. This is exemplified by means of one application with real data. 展开更多
关键词 DENDROGRAM FRACTAL axial symmetry engenderer.
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Simultaneous Exact Controllability of Wave Sound Propagations in Multilayer Media
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作者 Alexis Rodriguez Carranza Luis. J. Caucha Obidio Rubio Mercedes 《Journal of Mathematics and System Science》 2016年第8期323-329,共7页
In this work we study one problem of mathematical interest for their applications in several topics in Applied Science. We study simultaneous controllability of a pair of systems which model the evolution of sound in ... In this work we study one problem of mathematical interest for their applications in several topics in Applied Science. We study simultaneous controllability of a pair of systems which model the evolution of sound in a compressible flow considered as a transmission problem. We show the well posed of the problem. Furthermore provided appropriate conditions in the geometry of the domain are valid and suitable assumptions on the fluid, is possible to conduce the pair of systems to the equilibrium in a simultaneous way using only one control. 展开更多
关键词 CONTROLLABILITY wave sound H.U.M
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计算几何工具在机构分析中的应用
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作者 单锋英 林松 范意中 《机械设计与研究》 CSCD 北大核心 2014年第2期12-14,18,共4页
简要地介绍一种计算几何工具"Z.u.L."的特点和功能,探索了该工具在机构运动分析中的应用。通过对两个应用实例进行分析讨论,结果令人满意。该计算几何工具在机构分析领域中具有很好的应用前景,值得推广。
关键词 几何程序 机构运动分析
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An efficient numerical shape analysis for light weight membrane structures 被引量:12
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作者 Chao YANG Yan-bin SHEN Yao-zhi LUO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2014年第4期255-271,共17页
The determination of initial equilibrium shapes is a common problem in research work and engineering applications related to membrane structures. Using a general structural analysis framework of the finite particle me... The determination of initial equilibrium shapes is a common problem in research work and engineering applications related to membrane structures. Using a general structural analysis framework of the finite particle method (FPM), this paper presents the first application of the FPM and a recently-developed membrane model to the shape analysis of light weight mem- branes. The FPM is rooted in vector mechanics and physical viewpoints. It discretizes the analyzed domain into a group of parti- cles linked by elements, and the motion of the free particles is directly described by Newton's second law while the constrained ones follow the prescribed paths. An efficient physical modeling procedure of handling geometric nonlinearity has been developed to evaluate the particle interaction forces. To achieve the equilibrium shape as fast as possible, an integral-form, explicit time integration scheme has been proposed for solving the equation of motion. The equilibrium shape can be obtained naturally without nonlinear iterative correction and global stiffness matrix integration. Two classical curved surfaces of tension membranes pro- duced under the uniform-stress condition are presented to verify the accuracy and efficiency of the proposed method. 展开更多
关键词 Tension membranes Finite particle method (FPM) Shape analysis Explicit time integration Initial equilibriumshape
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On the Kahler-Ricci Flow on Projective Manifolds of General Type 被引量:5
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作者 Gang TIAN Zhou ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2006年第2期179-192,共14页
This note concerns the global existence and convergence of the solution for Kahler-Ricci flow equation when the canonical class, Kx, is numerically effective and big. We clarify some known results regarding this flow ... This note concerns the global existence and convergence of the solution for Kahler-Ricci flow equation when the canonical class, Kx, is numerically effective and big. We clarify some known results regarding this flow on projective manifolds of general type and also show some new observations and refined results. 展开更多
关键词 Geometric evolution equations Minimal model program
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