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Lipschitz Estimates for Commutators of N-dimensional Fractional Hardy Operators 被引量:8
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作者 ZHENG QING-YU Fu ZUN-WEI 《Communications in Mathematical Research》 CSCD 2009年第3期241-245,共5页
In this paper, it is proved that the commutator Hβ,b which is generated by the n-dimensional fractional Hardy operator Hβ and b ∈λα (R^n) is bounded from L^p(R^n) to L^q(R^n), where 0 〈 α 〈 1, 1 〈 p, q ... In this paper, it is proved that the commutator Hβ,b which is generated by the n-dimensional fractional Hardy operator Hβ and b ∈λα (R^n) is bounded from L^p(R^n) to L^q(R^n), where 0 〈 α 〈 1, 1 〈 p, q 〈 ∞ and 1/P - 1/q = (α+β)/n. Furthermore, the boundedness of Hβ,b on the homogenous Herz space Kq^α,p(R^n) is obtained. 展开更多
关键词 COMMUTATOR n-dimensional fractional Hardy operator Lipschitz function Herz space
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General calculation formulas and recurrence relations of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 被引量:1
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作者 CHENChang-yuan LUFa-lin SUNDong-sheng 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第3期432-440,共9页
In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix eleme... In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived. 展开更多
关键词 n-dimensional hydrogen atom-type potential Klein-Cordon equation Radial matrix dements GENERAL calculation FORMULAS RECURRENCE relations
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On Multiplicative Generators of n-Dimensional Overlap Functions 被引量:1
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作者 Hai Xie 《Applied Mathematics》 2020年第11期1061-1069,共9页
In this paper, inspired by the multiplicative generators of overlap functions, we mainly propose the concepts of multiplicative generator pairs of n-dimensional overlap functions, in order to extend the dimensionality... In this paper, inspired by the multiplicative generators of overlap functions, we mainly propose the concepts of multiplicative generator pairs of n-dimensional overlap functions, in order to extend the dimensionality of overlap functions from 2 to n. We present the condition under which the pair (<strong>g, h</strong>) can multiplicatively generate an n-dimensional overlap function <em><strong>O</strong></em><sub><strong>g,h</strong></sub><strong>.</strong> we focus on the homogeneity and idempotency property on multiplicatively generated n-dimensional overlap functions. 展开更多
关键词 n-dimensional Overlap Functions Overlap Functions Multiplicative Generators
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Solutions of Laplace Equation in n-Dimensional Spaces
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作者 冯晶晶 黄玲 杨师杰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第10期623-625,共3页
The solutions of the Laplace equation in n-dimensional space are studied. The angular eigenfunctions have the form of associated Jacob/polynomials. The radial solution of the Helmholtz equation is derived.
关键词 Laplace equation n-dimensional space associated Jacobi polynomials
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Relation Between Dimension and Angular Momentum for Radially Symmetric Potential in N-Dimensional Space
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作者 ZHAO Wei-Qin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3X期429-434,共6页
It is proved that when solving SchrSdinger equations for radially symmetric potentials the effect of higher dimensions on the radial wave function is equivalent to the effect of higher angular momenta in lower-dimensi... It is proved that when solving SchrSdinger equations for radially symmetric potentials the effect of higher dimensions on the radial wave function is equivalent to the effect of higher angular momenta in lower-dimensional cases. This result is applied to giving solutions for several radially symmetric potentials in N dimensions. 展开更多
关键词 n-dimensional Schrodinger equation radially symmetric potential dimension and angular momentum
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L_p(1≤p≤∞) APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A SET OF n+1 POINTS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1993年第4期430-436,共7页
Some new characterizations and immediate explicit expressions of best L(1≤p≤∞) approximation and their deviations by an n-dimensional subspace on a set of n+1 points are given.
关键词 APPROXIMATION BY AN n-dimensional SUBSPACE ON A SET OF n+1 POINTS L_p ID Case
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CANONICAL REPRESENTATIONS AND DEGREE OF FREEDOM FORMULAE OF ORTHOGONAL TENSORS IN N-DIMENSIONAL EUCLIDEAN SPACE
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作者 熊祝华 郑泉水 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第1期93-101,共9页
In this paper, with the help of the eigenvalue properties of orthogonal tensors in n-dimensional Euclidean space and the representations of the orthogonal tensors in 2-dimensional space, the canonical representations ... In this paper, with the help of the eigenvalue properties of orthogonal tensors in n-dimensional Euclidean space and the representations of the orthogonal tensors in 2-dimensional space, the canonical representations of orthogonal tensors in n-dimensional Euclidean space are easily gotten. The paper also gives all the constraint relationships among the principal invariants of arbitrarily given orthogonal tensor by use of Cayley-Hamilton theorem; these results make it possible to solve all the eigenvalues of any orthogonal tensor based on a quite reduced equation of m-th order, where m is the integer part ofn \2. Finally, the formulae of the degree of freedom of orthogonal tensors are given. 展开更多
关键词 CANONICAL REPRESENTATIONS AND DEGREE OF FREEDOM FORMULAE OF ORTHOGONAL TENSORS IN n-dimensional EUCLIDEAN SPACE exp
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一种数据立方高效索引机制——CuboidTree
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作者 吴永英 司宏杰 王晓鹏 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第1期16-18,共3页
提出了一种高效的数据立方索引机制CuboidTree ,利用Z Order编码以保持同一数据小方内立方元组之间的多维空间邻近性 ,将数据立方查询归结为针对其中某个特定数据小方的查询 ,从而将同一数据小方中的立方元组聚簇在一起以加速响应数据... 提出了一种高效的数据立方索引机制CuboidTree ,利用Z Order编码以保持同一数据小方内立方元组之间的多维空间邻近性 ,将数据立方查询归结为针对其中某个特定数据小方的查询 ,从而将同一数据小方中的立方元组聚簇在一起以加速响应数据立方查询 .对模拟数据和真实数据进行的实验表明 ,CuboidTree不仅可以明显地提高数据立方范围查询的性能 ,而且节省了存储空间 。 展开更多
关键词 数据立方 索引机制 cuboidTree 数据小方 zkdB-Tree 联机分析处理 数据查询 聚簇
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基于Cuboids特征的多类超球面支持向量机动作识别研究
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作者 高晶 王韶霞 《廊坊师范学院学报(自然科学版)》 2012年第2期29-32,共4页
基于超球面支持向量机,利用多类超球面支持向量机结合Cuboids时空兴趣点进行动作识别,在KTH、Weizmann两个数据库上进行仿真实验,取得了满意的效果。
关键词 多类超球面支持向量机 cuboids时空兴趣点 动作识别
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Singularity-free expression of magnetic field of cuboid under undulating terrain 被引量:4
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作者 匡星涛 杨海 +1 位作者 朱晓颖 李伟 《Applied Geophysics》 SCIE CSCD 2016年第2期238-248,416,共12页
Most of the current computing methods used to determine the magnetic field of a uniformly magnetized cuboid assume that the observation point is located in the upper half space without a source. However, such methods ... Most of the current computing methods used to determine the magnetic field of a uniformly magnetized cuboid assume that the observation point is located in the upper half space without a source. However, such methods may generate analytical singularities for conditions of undulating terrain. Based on basic geomagnetic field theories, in this study an improved magnetic field expression is derived using an integration method of variable substitution, and all singularity problems for the entire space without a source are discussed and solved. This integration process is simpler than that of previous methods, and final integral results with a more uniform form. AT at all points in the source-flee space can be calculated without requiring coordinate transformation; thus forward modeling is also simplified. Corresponding model tests indicate that the new magnetic field expression is more correct because there is no analytical singularity and can be used with undulating terrain. 展开更多
关键词 Undulating terrain magnetic field of cuboid variable substitution analytical singularity
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Update on diagnosis and management of cuboid fractures 被引量:2
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作者 Antonios G Angoules Nikolaos A Angoules +1 位作者 Michalis Georgoudis Stylianos Kapetanakis 《World Journal of Orthopedics》 2019年第2期71-80,共10页
Cuboid fractures due to the particular bone anatomy and its protected location in the midfoot are rare, and they are usually associated with complex injuries of the foot. Clinical examination to diagnose these fractur... Cuboid fractures due to the particular bone anatomy and its protected location in the midfoot are rare, and they are usually associated with complex injuries of the foot. Clinical examination to diagnose these fractures should be detailed and the differential diagnosis, especially in the case of vague symptoms, should include the exclusion of all lateral foot pain causes. Conventional radiographs do not always reveal occult fractures, which can be under diagnosed especially in children. In this case, further investigation including magnetic resonance imaging or scintigraphy may be required. The treatment of these injuries depends on the particular fracture characteristics. Non-displaced isolated fractures of the cuboid bone can be effectively treated conservatively by immobilization and by avoiding weight bearing on the injured leg. In the case of shortening of the lateral column> 3 mm or articular displacement > 1 mm, surgical management of the fracture is mandatory in order to avoid negative biomechanical and functional consequences for the foot and adverse effects such as arthritis and stiffness as well as painful gait. In this review, an update on diagnosis and management of cuboid fractures is presented. 展开更多
关键词 cuboid FRACTURE DIAGNOSIS Treatment SURGERY
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Simplified Computation of Reflective Overpressure in Closed Cuboid Space Due to Internal Explosion 被引量:2
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作者 田力 李忠献 周清 《Transactions of Tianjin University》 EI CAS 2010年第6期395-404,共10页
A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all node... A simplified method is proposed for analyzing the overpressure history of an optional point on the walls of a closed cuboid due to its internal optional point-explosion. Firstly, the overpressure histories of all nodes on the walls of a cube with a side-length of 2 m are computed under a reference-charge explosion at each node of its inner space using the LS-DYNA software, and then are collected to form a reference database. Next, with the thought of the isoparametric finite element, an interpolating algori... 展开更多
关键词 closed cuboid space reference database reflective overpressure charge weight
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基于PE-Cuboid特征的人体行为识别算法 被引量:1
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作者 陶玲 《电脑知识与技术》 2014年第2X期1287-1290,共4页
为了克服单纯使用局部时空兴趣点(spatial-temporal interest point,STIP)的方法在对视频序列中人体行为进行识别时提取的特征点太少,且其不能完整的表征图像的特征,提出一种结合局部特征和全局特征的特征描述子PE-Cuboid,能有效的提高... 为了克服单纯使用局部时空兴趣点(spatial-temporal interest point,STIP)的方法在对视频序列中人体行为进行识别时提取的特征点太少,且其不能完整的表征图像的特征,提出一种结合局部特征和全局特征的特征描述子PE-Cuboid,能有效的提高人体行为识别的正确率。对每一个视频序列提取PE-Cuboid特征,利用像素变化概率图(PCRM)和边缘方向直方图(EOH)捕捉全局运动信息,局部的Cuboid描述子对全局特征做进一步区分,对最终生成的PE-Cuboid特征进行K-means聚类形成视觉词汇本(visual dictionary),将视觉词汇本输入到线性SVM分类器(linear Support Vector Machines,LSVM)中进行学习、训练、分类,最后采用打分的机制得到行为类别。该文算法在KTH、Weizmann行为数据库和我们自拍测试集中都做了测试,实验结果显示算法具有较高的识别率。 展开更多
关键词 行为识别 时空兴趣点 PE-cuboid 支持向量机
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Preparation, Structures and Magnetic Properties of Two Co-based Clusters with Triangular Core and Cuboidal Core Geometries
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作者 LI Qi-Peng SHEN Yan-Qiong QIAN Jin-Jie 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第11期1934-1939,共6页
Two novel Co-based clusters with the 2-(hydroxylmethyl)pyridine(hmpH)ligand,formulated as[Co3(hmp)6(hmpH)]×2NO3×3H2O(ZTU-3)and[Co4(hmp)4(CH3CO2)2(H2O)4]×2NO3(ZTU-4),have been successfully synthesized an... Two novel Co-based clusters with the 2-(hydroxylmethyl)pyridine(hmpH)ligand,formulated as[Co3(hmp)6(hmpH)]×2NO3×3H2O(ZTU-3)and[Co4(hmp)4(CH3CO2)2(H2O)4]×2NO3(ZTU-4),have been successfully synthesized and structurally characterized.ZTU-3 features a triangular core geometry,while ZTU-4 exhibits a cuboidal core geometry.In addition,the magnetic properties of ZTU-3 and ZTU-4 are also all investigated. 展开更多
关键词 Co-based clusters triangular core cuboidal core magnetic property
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Application of Ant Colony Optimization for the Solution of 3 Dimensional Cuboid Structures 被引量:1
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作者 Hüseyin Eldem Erkan Ulker 《Journal of Computer and Communications》 2014年第4期99-107,共9页
Traveling Salesman Problem (TSP) is one of the most widely studied real world problems of finding the shortest (minimum cost) possible route that visits each node in a given set of nodes (cities) once and then returns... Traveling Salesman Problem (TSP) is one of the most widely studied real world problems of finding the shortest (minimum cost) possible route that visits each node in a given set of nodes (cities) once and then returns to origin city. The optimization of cuboid areas has potential samples that can be adapted to real world. Cuboid surfaces of buildings, rooms, furniture etc. can be given as examples. Many optimization algorithms have been used in solution of optimization problems at present. Among them, meta-heuristic algorithms come first. In this study, ant colony optimization, one of meta-heuristic methods, is applied to solve Euclidian TSP consisting of nine different sized sets of nodes randomly placed on a cuboid surface. The performance of this method is shown in tests. 展开更多
关键词 Euclidean TSP Ant Colony Optimization METAHEURISTIC PATH-RELINKING Path Planning cuboid
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The formation of orthogonal joint systems and cuboidal blocks:New insights gained from flat-lying limestone beds in the region of Havre-Saint-Pierre(Quebec,Canada)
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作者 Shaocheng Ji Yvéric Rousseau +1 位作者 Denis Marcotte Noah John Phillips 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3079-3093,共15页
Vertical orthogonal joints are a common feature in shallow crustal rocks.There are several competing theories for their formation despite the ubiquity.We examined the exceptional exposures of orthogonal joints in flat... Vertical orthogonal joints are a common feature in shallow crustal rocks.There are several competing theories for their formation despite the ubiquity.We examined the exceptional exposures of orthogonal joints in flat-lying Ordovician limestone beds from the Havre-Saint-Pierre Region in Quebec,Canada(north shore of Saint-Lawrence River)to test conceptual models of joint formation in a natural setting.In the region,the spacing of cross-joints is consistently larger than the spacing of systematic joints by a factor of 1.5 approximately.The joint-spacing-to-bed-thickness ratios(s/t)are much larger in these beds(s/t=4.3 for systematic joints,and 6.4 for cross-joints)than those in higher strained strata along the south shore of the Saint-Lawrence River(s/t=1),highlighting the effect of tectonic strain in decreasing fracture spacing and block size.The high values of s/t indicate that cross-joint formation was unlikely caused by a switch from compression to tension once a critical s/t ratio for systematic joints was reached(as hypothesized in previous studies).We proposed a new model for the formation of orthogonal joint systems where the principal stress axes locally switch during the formation of systematic fractures.The presence of ladder-shaped orthogonal joints suggests a state of effective stress withσ_(1)^(∗)≫0>σ_(2)^(∗)>σ_(3)^(∗)and whereσ_(2)^(∗)-σ_(3)^(∗)is within the range of fracture strength variability at the time of fracture.This research provides a new mechanical model for the formation of orthogonal joint systems and cuboidal blocks. 展开更多
关键词 Plato's cuboids Orthogonal joints Fracture spacing LIMESTONE Layered rock mechanics Appalachian geology
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潮汐影响下基于长方体排列的船舶调度问题研究
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作者 文捷 刘昊雨 +3 位作者 王永才 李春旭 苏建光 张蕾 《中国航海》 CSCD 北大核心 2024年第3期81-88,共8页
大型港口的泊位分配与船舶调度是决定港口吞吐量和运行效率的关键问题。船舶在选择泊位停靠时受泊位空闲时间、泊位长度、泊位实时水深等多方面的因素影响,优化目的是缩短船舶的平均等待时间或总等待时间。本文研究面向青岛港的泊位分... 大型港口的泊位分配与船舶调度是决定港口吞吐量和运行效率的关键问题。船舶在选择泊位停靠时受泊位空闲时间、泊位长度、泊位实时水深等多方面的因素影响,优化目的是缩短船舶的平均等待时间或总等待时间。本文研究面向青岛港的泊位分配与船舶调度问题,在考虑潮汐影响下,提出长方体排列模型,描述潮汐影响下船舶有不同吃水深度、不同类型、不同服务时间需求的船舶调度问题。在所提模型基础上,设计了两阶段贪心算法和船舶优先级与泊位分配的二维遗传算法,通过仿真数据和青岛港的真实数据验证了该方法的有效性。 展开更多
关键词 泊位分配与船舶调度 潮汐影响 长方体排列 两阶段贪心算法 二维遗传算法
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矩形/长方体网格单元时间高阶有限差分波场数值模拟
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作者 徐世刚 黄兴国 +2 位作者 韩丽 包乾宗 任志明 《石油地球物理勘探》 EI CSCD 北大核心 2024年第5期976-988,共13页
有限差分法在求解不同类型地震波动方程中广泛应用,提高有限差分在时间域和空间域的地震波场数值模拟精度十分重要。为了提高现有时间—空间域高阶差分方法的精度和灵活性,提出了基于矩形/长方体网格单元的改进时间—空间高阶有限差分方... 有限差分法在求解不同类型地震波动方程中广泛应用,提高有限差分在时间域和空间域的地震波场数值模拟精度十分重要。为了提高现有时间—空间域高阶差分方法的精度和灵活性,提出了基于矩形/长方体网格单元的改进时间—空间高阶有限差分方案,分别求解二维和三维声波方程。改进差分法主要通过联合旁轴网格节点和传统轴向节点来共同完成偏导数近似,进一步结合平面波理论和泰勒级数展开求取改进模板中的高阶差分系数。数值精度分析表明,改进差分方案相较于传统方法具有更高的数值精度和稳定性。多个模型算例表明,在相同参数条件下,改进差分方法在兼顾空间模拟精度的前提下能够提高时间模拟精度。此外,改进模板沿不同空间方向可以选用不同的网格步长,有效增加了波场模拟的灵活性,能够为后续的地震成像和反演提供有效波场延拓工具。 展开更多
关键词 地震波动方程 正演模拟 高阶有限差分 矩形/长方体网格 差分系数
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Detection of functional diversity gradients and their geoclimatic filters is sensitive to data types(occurrence vs.abundance)and spatial scales(sites vs.regions)
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作者 JoséLuiz Alves Silva Alexandre Souza Angela Pierre Vitória 《Plant Diversity》 SCIE CAS CSCD 2024年第6期732-743,共12页
Functional diversity(FD)reflects within-and between-site variation of species traits(α-and β-FD,respectively).Understanding how much data types(occurrence-based vs.abundance-weighted)and spatial scales(sites vs.regi... Functional diversity(FD)reflects within-and between-site variation of species traits(α-and β-FD,respectively).Understanding how much data types(occurrence-based vs.abundance-weighted)and spatial scales(sites vs.regions)change FD and ultimately interfere with the detection of underlying geoclimatic filters is still debated.To contribute to this debate,we explored the occurrence of 1690 species in 690 sites,abundances of 1198 species in 343 sites,and seven functional traits of the Atlantic Forest woody flora in South America.All FD indices were sensitive and dependent on the data type at both scales,with occurrence particularly increasing a richness and dispersion(occurrence>abundance in 80%of the sites)while abundance increased β total,β replacement,and α evenness(abundance>occurrence in 60%of the sites).Furthermore,detecting the effect of geoclimatic filters depended on the data type and was scale-dependent.At the site scale,precipitation seasonality and soil depth had weak effects on α-and β-FD(max.R^(2)=0.11).However,regional-scale patterns of a richness,dispersion,and evenness strongly mirrored the variation in precipitation seasonality,soil depth,forest stability over the last 120 kyr,and cation exchange capacity(correlations>0.80),suggesting that geoclimatic filters manifest stronger effects at the regional scale.Also,the role of edaphic gradients expands the idea of biogeographical filters beyond climate.Our findings caution functional biogeographic studies to consider the effect of data type and spatial scale before designing and reaching ecological conclusions about the complex nature of FD. 展开更多
关键词 Environmental filtering Historical events Human pressure n-dimensional hypervolume Biodiversity hotspot Tropical forest
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长方体劈裂试验的可行性研究 被引量:5
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作者 刘勇军 朱岳明 +1 位作者 曹为民 沈洪俊 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第5期100-102,共3页
分析了长方体劈裂试验的可行性 ,得到了抗拉强度值和试件尺寸的关系 ,并且找到了可替代巴西试验的长方体宽高比范围 ,对各种宽高比所得的拉应力值进行误差分析和优劣对比 。
关键词 长方体 抗拉强度 劈裂试验 可行性
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