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新课改下高中数学向量的教学研究 被引量:3
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作者 梁小波 《求知导刊》 2016年第13期22-22,共1页
在新课改背景下,高中课程逐渐引入向量相关知识,直接影响了数学教学的解题方式、课程教学结构,为了有效落实新课改的具体要求,进行数学向量的教学研究具有重要意义。本文主要研究新课改下高中数学向量教学过程中存在的主要问题,提出有... 在新课改背景下,高中课程逐渐引入向量相关知识,直接影响了数学教学的解题方式、课程教学结构,为了有效落实新课改的具体要求,进行数学向量的教学研究具有重要意义。本文主要研究新课改下高中数学向量教学过程中存在的主要问题,提出有效的教学对策,为高中数学向量教学提供参考。 展开更多
关键词 教学研究 数学向量 高中 新课改
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翻转课堂教学模式在Moodle平台中的实现——以高一数学《向量的加法及其运算律》为例 被引量:1
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作者 曾菲 《教育信息技术》 2015年第4期42-44 41,41,共4页
翻转课堂是指首先由教师创建教学微课视频,学生在家或课外观看视频讲解,然后再回到课堂中进行师生、生生间面对面的分享、交流学习成果与心得的一种教学模式。Moodle是指模块化面向对象的动态学习环境。本文旨在通过《向量的加法及其运... 翻转课堂是指首先由教师创建教学微课视频,学生在家或课外观看视频讲解,然后再回到课堂中进行师生、生生间面对面的分享、交流学习成果与心得的一种教学模式。Moodle是指模块化面向对象的动态学习环境。本文旨在通过《向量的加法及其运算律》课程的教学,展示翻转数学课堂的教学模式如何利用微课视频等各种网络教学资源,借助Moodle平台等多种信息技术手段来得到更好的实现。 展开更多
关键词 翻转课堂 MOODLE平台 微课 高中数学平面向量
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向量数学库的向量化方法研究 被引量:9
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作者 周蓓 黄永忠 +1 位作者 许瑾晨 郭绍忠 《计算机科学》 CSCD 北大核心 2019年第1期320-324,共5页
SIMD技术的出现使得基础数学库扩展到向量数学库成为必然趋势。基础数学库中多数函数存在代码实现复杂、分支判断多的特点,增加了向量化的难度,同时SIMD指令的不完备导致函数中的部分功能无法直接向量化,频繁的拆分和拼接操作降低了函... SIMD技术的出现使得基础数学库扩展到向量数学库成为必然趋势。基础数学库中多数函数存在代码实现复杂、分支判断多的特点,增加了向量化的难度,同时SIMD指令的不完备导致函数中的部分功能无法直接向量化,频繁的拆分和拼接操作降低了函数的性能。针对这些问题,提出了向量数学库的向量化方法,通过确定核心代码段、数据预处理过程向量化及指令向量化3个步骤,可以快速有效地对基础数学库进行向量化。实验表明,运用该方法,exp,pow,log10等典型函数的性能平均提高了24.2%。 展开更多
关键词 SIMD技术 向量数学 核心代码段 数据预处理 指令向量
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基于飞腾M6678的向量数学库优化技术研究 被引量:1
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作者 王正行 曾令将 《舰船电子工程》 2021年第3期102-106,共5页
不同于传统的标量数学计算,向量数学库提供的加速比高,能够充分利用飞腾M6678的并行计算能力。文章比较了现有的数学函数库,包括标准C数学函数库和TI公司的MAHLIB函数库的运算性能,发现MATHLIB函数库部分函数向量化程度低,可向量化的空... 不同于传统的标量数学计算,向量数学库提供的加速比高,能够充分利用飞腾M6678的并行计算能力。文章比较了现有的数学函数库,包括标准C数学函数库和TI公司的MAHLIB函数库的运算性能,发现MATHLIB函数库部分函数向量化程度低,可向量化的空间较大。向量函数库选择级数法实现,为使用飞腾M6678的指令集RCPSP和RSQRSP,引入了牛顿迭代法。以开平方运算为例,文章通过深入分析单次循环体内资源占用的情况,详细说明了如何确定一个函数的计算瓶颈。根据瓶颈的不同,选择对应的SIMD优化方法,以及基于飞腾M6678硬件特性的优化方法,构建了一个高性能的向量数学库。测试结果表明,向量数学库典型函数的性能提升可达150%至700%。 展开更多
关键词 性能优化 M6678 向量数学 牛顿迭代法 SIMD
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向量回转及向量微回转代数(英文)
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作者 毛明 张相麟 程瑞廷 《北京理工大学学报》 EI CAS CSCD 1990年第S1期12-18,共7页
向量回转作为刚体转动的一种描述,不仅简便而且直观。本文补充和发展了向量的回转及微回转代数。共为轭曲面原理,机构分析的有限微回转法及共轭弹性动力学奠定了必要的数学基础。
关键词 转动 向量(数学) 机构运动分析/有限微回转法
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平面向量在力学中的应用
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作者 严少林 《学生·家长·社会》 2021年第2期298-298,300,共2页
在教育部考试中心颁发的《物理科考试大纲》中,把物理学科能力归纳为五种能力,即理解能力、推理能力、分析综合能力、用数学方法处理物理问题的能力和实验探究能力等。在用数学方法处理物理问题的能力中,大家重视研究的是代数方法,如极... 在教育部考试中心颁发的《物理科考试大纲》中,把物理学科能力归纳为五种能力,即理解能力、推理能力、分析综合能力、用数学方法处理物理问题的能力和实验探究能力等。在用数学方法处理物理问题的能力中,大家重视研究的是代数方法,如极值方法,函数方法,图象方法等等,而对于用平面向量的方法解决物理问题,研究较少。本文研究用平面向量的方法解决高中物理题。 展开更多
关键词 物理知识 转化 数学向量问题 数形结合
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船用中速柴油机故障诊断技术研究 被引量:2
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作者 陈智君 周小康 余永华 《中国修船》 2021年第2期20-24,共5页
为了提高船舶柴油机故障诊断的准确性,实现对故障的精准定位,文章以6DE-18型船用中速柴油机为研究对象,从故障产生的机理入手,采用仿真软件建模,选取具有代表性的热力参数作为特征值,运用粒子群算法优化的支持向量机数学模型(PSO-SVM)... 为了提高船舶柴油机故障诊断的准确性,实现对故障的精准定位,文章以6DE-18型船用中速柴油机为研究对象,从故障产生的机理入手,采用仿真软件建模,选取具有代表性的热力参数作为特征值,运用粒子群算法优化的支持向量机数学模型(PSO-SVM)进行故障诊断,并通过试验验证该故障诊断的准确性,改进了船用中速柴油机故障诊断的模式,提高了船舶柴油机的经济性和安全性。 展开更多
关键词 故障诊断 仿真建模 支持向量数学模型
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基于支持向量机的进口煤炭相关指标间数学模型的建立
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作者 管嵩 郭兵 +1 位作者 王越 刘宝 《中国科技成果》 2017年第2期35-36,共2页
建立起进口煤炭来源国、煤种的支持向量机数学模型,在统计样本量较少的情况下,获得更好的泛化能力和良好的统计规律,有效地利用以前积累的多种线性或非线性数据信息,开发应用了进口煤炭数据分析及管理系统,对进口煤炭各项指标之间... 建立起进口煤炭来源国、煤种的支持向量机数学模型,在统计样本量较少的情况下,获得更好的泛化能力和良好的统计规律,有效地利用以前积累的多种线性或非线性数据信息,开发应用了进口煤炭数据分析及管理系统,对进口煤炭各项指标之间的关系进行研究,并动态收集进口煤炭检验信息,为检验检疫工作提供技术支撑,也为辅助实验室进行质量管理。 展开更多
关键词 进口煤炭 支持向量数学模型 煤炭数据分析及管理系统 质量管理
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Characteristics of a Terrain-Following Sigma Coordinate 被引量:1
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作者 LI Yi-Yuan WANG Bin WANG Dong-Hai 《Atmospheric and Oceanic Science Letters》 2011年第3期157-161,共5页
This study quantifies the main characteristics of a terrain-following, G-coordinate through mathematical analyses of its covariant and contravariant basis vectors as well as the vertical coordinate of σ. A 3-D schema... This study quantifies the main characteristics of a terrain-following, G-coordinate through mathematical analyses of its covariant and contravariant basis vectors as well as the vertical coordinate of σ. A 3-D schematic of the σ-coordinate in a curvilinear coordinate system is provided in this study. The characteristics of the basis vectors were broken down into their "local vector charac- teristics" and "spatial distribution characteristics", and the exact expressions of the covariant; in addition, the con- travariant basis vectors of the G-coordinate used to eluci- date their detailed characteristics were properly solved. Through rewriting the expression of the vertical coordi- nate of G, a mathematical expression of all the cr-coor- dinate surfaces was found, thereby quantifying the so- called terrain-following characteristics and lack of flexi- bility to adjust the slope variation of G-coordinate sur- faces for the classic definition of G. Finally, an analysis on the range value of the vertical coordinate demonstrated that the general value range of G could be obtained by eliminating the G-coordinate surfaces below the Earth's surface. All these quantitative descriptions of the charac- teristics of G-coordinate were the foundation for improv- ing the G-coordinate or creating a new one. 展开更多
关键词 quantitative description sigma coordinate 3-D schematic basis vectors non-orthogonal
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Characterizations of Orthogonal Vector-valued Multivariate Wavelet Packets
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作者 HUA De-lin FENG Jin-shun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期606-614,共9页
In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties ar... In this paper, the notion of orthogonal vector-valued wavelet packets of space L2 (R^s, C^n) is introduced. A procedure for constructing the orthogonal vector-valued wavelet packets is presented. Their properties are characterized by virtue of time-frequency analysis method, matrix theory and finite group theory, and three orthogonality formulas are obtained. Finally, new orthonormal bases of space L2(R^s,C^n) are extracted from these wavelet packets. 展开更多
关键词 ORTHOGONALITY refinement equation vector-valued multiresolution analysis vector-valued scaling function vector-valued wavelet packets
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Formulation of Green's Function in Solving Schroedinger Equation forBipartite System with Kinetic Coupling Gained by Virtue of Entangled States
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作者 FANHong-Yi LIUQiu-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期791-794,共4页
Using the entangled state representation we present a formulation of Green'sfunction in solving Schrodinger equation for bipartite system with kinetic coupling.
关键词 Green's function bipartite system kinetic coupling entangled staterepresentation
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Asymmetrical Quantum Encryption Protocol Based on Quantum Search Algorithm 被引量:2
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作者 LUO Wenjun LIU Guanli 《China Communications》 SCIE CSCD 2014年第9期104-111,共8页
Quantum cryptography and quantum search algorithm are considered as two important research topics in quantum information science.An asymmetrical quantum encryption protocol based on the properties of quantum one-way f... Quantum cryptography and quantum search algorithm are considered as two important research topics in quantum information science.An asymmetrical quantum encryption protocol based on the properties of quantum one-way function and quantum search algorithm is proposed.Depending on the no-cloning theorem and trapdoor one-way functions of the publickey,the eavesdropper cannot extract any private-information from the public-keys and the ciphertext.Introducing key-generation randomized logarithm to improve security of our proposed protocol,i.e.,one privatekey corresponds to an exponential number of public-keys.Using unitary operations and the single photon measurement,secret messages can be directly sent from the sender to the receiver.The security of the proposed protocol is proved that it is informationtheoretically secure.Furthermore,compared the symmetrical Quantum key distribution,the proposed protocol is not only efficient to reduce additional communication,but also easier to carry out in practice,because no entangled photons and complex operations are required. 展开更多
关键词 quantum cryptography asymmetrical encryption information-theoreticalsecurity quantum search algorithms
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模糊检索在DBASEⅡ关系数据库上的实现
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作者 梁锦华 《广州师院学报(自然科学版)》 1993年第2期28-34,共7页
本文依据检索系统的向量检索数学模型,DBASEⅢ关系数据库支持下,提出了一种在文献管理系统中实现模糊检索的方案,方案允许对文献标引词和检索提问词进行加权,能更准确地描述文献的特征和表达检索者的提问要求,从而提高了检索的查... 本文依据检索系统的向量检索数学模型,DBASEⅢ关系数据库支持下,提出了一种在文献管理系统中实现模糊检索的方案,方案允许对文献标引词和检索提问词进行加权,能更准确地描述文献的特征和表达检索者的提问要求,从而提高了检索的查全率或查准率,输出文献按文献与提问的符合度大小排序,用户可以通过阈值控制输出文献的数量。笔者进行了模拟试验,软硬件环境:IBM286兼容机,时种21M,3.5英寸,华达CCDOS,MFOXPLUS2.0。主题词库:2500个词,文献库:2万条记录,编号对照文件:10万条记录,平均每个主题词对应40篇文献。系统:输入n个提问词检索,约需时间2n-3n秒。若使用虚拟盘进行中间运算,则只需时约1.5n秒。 展开更多
关键词 模糊检索 文献检索 主题检索 DBASEⅢ关系数据库 文献管理系统 向量检索数学模型
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Extending self-organizing maps for supervised classification of remotely sensed data 被引量:1
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作者 CHEN Yongliang 《Global Geology》 2009年第1期46-56,共11页
An extended self-organizing map for supervised classification is proposed in this paper. Unlike other traditional SOMs, the model has an input layer, a Kohonen layer, and an output layer. The number of neurons in the ... An extended self-organizing map for supervised classification is proposed in this paper. Unlike other traditional SOMs, the model has an input layer, a Kohonen layer, and an output layer. The number of neurons in the input layer depends on the dimensionality of input patterns. The number of neurons in the output layer equals the number of the desired classes. The number of neurons in the Kohonen layer may be a few to several thousands, which depends on the complexity of classification problems and the classification precision. Each training sample is expressed by a pair of vectors : an input vector and a class codebook vector. When a training sample is input into the model, Kohonen's competitive learning rule is applied to selecting the winning neuron from the Kohouen layer and the weight coefficients connecting all the neurons in the input layer with both the winning neuron and its neighbors in the Kohonen layer are modified to be closer to the input vector, and those connecting all the neurons around the winning neuron within a certain diameter in the Kohonen layer with all the neurons in the output layer are adjusted to be closer to the class codebook vector. If the number of training sam- ples is sufficiently large and the learning epochs iterate enough times, the model will be able to serve as a supervised classifier. The model has been tentatively applied to the supervised classification of multispectral remotely sensed data. The author compared the performances of the extended SOM and BPN in remotely sensed data classification. The investigation manifests that the extended SOM is feasible for supervised classification. 展开更多
关键词 Self-organizing map modified competitive learning supervised classification remotely sensed data
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Using Support Vector Regression to Analyze Urban Atmosphere Pollution with Optical Remote Sensing Data
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作者 Yansong Xue Le Yu +1 位作者 Kai Cao Pengwei XH 《Journal of Earth Science and Engineering》 2013年第3期180-189,共10页
The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorith... The concentration of absorbable particulate matter less than 10 μm termed as PM10 is the most important urban air pollution index for air quality monitoring. This paper presents a space based PM10 monitoring algorithm based on QUAC (QUick atmosphere correction) for optical remote sensing data and SVR (support vector regression). PM 10 concentration measurements from nine ground based stations in Hangzhou, China and the MODIS (moderate-resolution imaging spectroradiometer) images were analyzed. Experimental result indicates that the correlation between CD (correction differences) with actual measured data is better than correlation between AOD (aerosol optical depth) with measured data. In addition, the fitting performance of the SVR model established with CD and measured data is better than traditional regression models. 展开更多
关键词 MODIS PMIO QUAC SVR.
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单十字轴万向节十字轴的运动分析及仿真 被引量:10
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作者 范景峰 李大磊 《机械传动》 CSCD 北大核心 2016年第3期131-133,共3页
对单十字轴万向节的十字轴运动规律进行了分析,运用数学向量方法求得十字轴万向节的传递运动规律,以及十字轴平面法线运动轨迹方程;运用Solid Works Motion软件来仿真单十字轴万向节中十字轴平面法线的运动轨迹,对比仿真所得的波动图与... 对单十字轴万向节的十字轴运动规律进行了分析,运用数学向量方法求得十字轴万向节的传递运动规律,以及十字轴平面法线运动轨迹方程;运用Solid Works Motion软件来仿真单十字轴万向节中十字轴平面法线的运动轨迹,对比仿真所得的波动图与理论计算所得的方程,验证了理论分析结果的正确性,为单十字轴万向节的运动优化设计提供理论依据,同时在空间上,为单十字轴万向节转向系的空间布置提供理论参考。 展开更多
关键词 单十字轴万向节 数学向量 运动分析 SOLIDWORKS MOTION
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Error Analysis on Hérmite Learning with Gradient Data 被引量:1
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作者 Baohuai SHENG Jianli WANG Daohong XIANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2018年第4期705-720,共16页
This paper deals with Hermite learning which aims at obtaining the target function from the samples of function values and the gradient values. Error analysis is conducted for these algorithms by means of approaches f... This paper deals with Hermite learning which aims at obtaining the target function from the samples of function values and the gradient values. Error analysis is conducted for these algorithms by means of approaches from convex analysis in the frame- work of multi-task vector learning and the improved learning rates are derived. 展开更多
关键词 Hermite learning Gradient learning Learning rate Convex analysis Multitask learning Differentiable reproducing kernel Hilbert space
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A Criterion for Existence of Bivariate Vector Valued Rational Interpolants 被引量:1
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作者 TAO You Tian ZHU Xiao Lin ZHOU Jin Ming 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第3期682-690,共9页
In this paper,a necessary and sufficient condition for the existence of a kind of bivariate vector valued rational interpolants over rectangular grids is given.This criterion is an algebraic method,i.e.,by solving a s... In this paper,a necessary and sufficient condition for the existence of a kind of bivariate vector valued rational interpolants over rectangular grids is given.This criterion is an algebraic method,i.e.,by solving a system of equations based on the given data,we can directly test whether the relevant interpolant exists or not.By coming up with our method, the problem of how to deal with scalar equations and vector equations in the same system of equations is solved.After testing existence,an expression of the corresponding bivariate vector-valued rational interpolant can be constructed consequently.In addition,the way to get the expression is different from the one by making use of Thiele-type bivariate branched vector-valued continued fractions and Samelson inverse which are commonly used to construct the bivariate vector-valued rational interpolants.Compared with the Thiele-type method,the one given in this paper is more direct.Finally,some numerical examples are given to illustrate the result. 展开更多
关键词 bivariate Newton interpolation formula bivariate vector-valued rational interpolants EXISTENCE necessary and sufficient conditions.
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Proper Conformal Killing Vectors in Kantowski-Sachs Metric
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作者 Tahir Hussain Muhammad Farhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第4期393-398,共6页
This paper deals with the existence of proper conformal Killing vectors(CKVs) in Kantowski-Sachs metric.Subject to some integrability conditions, the general form of vector filed generating CKVs and the conformal fact... This paper deals with the existence of proper conformal Killing vectors(CKVs) in Kantowski-Sachs metric.Subject to some integrability conditions, the general form of vector filed generating CKVs and the conformal factor is presented. The integrability conditions are solved generally as well as in some particular cases to show that the nonconformally flat Kantowski-Sachs metric admits two proper CKVs, while it admits a 15-dimensional Lie algebra of CKVs in the case when it becomes conformally flat. The inheriting conformal Killing vectors(ICKVs), which map fluid lines conformally, are also investigated. 展开更多
关键词 conformal killing vectors killing vectors Kantowski-Sachs metric
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On the Critical Behavior of Gapped Gravitational Collapse in Confined Spacetime
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作者 Rong-Gen Cai Li-Wei Ji Run-Qiu Yang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第7期67-75,共9页
The gravitational collapse of a massless scalar with a cosmological constant A is investigated. The mass field enclosed with a perfectly reflecting wall in a spacetime scaling for the gapped collapse MAH -- Mg oc (ec... The gravitational collapse of a massless scalar with a cosmological constant A is investigated. The mass field enclosed with a perfectly reflecting wall in a spacetime scaling for the gapped collapse MAH -- Mg oc (ec -- e) is confirmed and a new time scaling for the gapped collapse Tall -- Tg c( (ec - e)〈 is found. For both the critical exponents, we find strong evidence to show that they are non-universal. Especially when A ~ O, we find that both of these two critical exponents depend on the combination AR2, where R is the radial position of the reflecting wall. We find an evolution of the critical exponent from 0.37 in the confined asymptotic dS case with AR2 = 1.75 to 0.68 in the confined asymptotic AdS case with AR2 -- -1.75, while the critical exponent ( varies from 0.10 to 0.26, which shows that the new critical behavior for the gapped collapse is essentially different from the Choptuik's case. 展开更多
关键词 black hole formation cosmological constant gravitation collapse critical phenomenon
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