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基于最优k值k-means聚类分析的湖相沉积土层岩土参数分布研究 被引量:1
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作者 阮永芬 李鹏辉 +3 位作者 张虔 朱强 王勇 闫明 《贵州大学学报(自然科学版)》 2023年第2期89-96,共8页
对岩土参数进行传统的k-means聚类分析时,因无法确定k值,而导致无法有效剔除误差数据。为得到岩土参数可靠取值范围,基于最优k值的k-means算法进行研究,通过量化样本内距离和聚类紧密性来确定聚类数目k值,避免了传统k值的随机选取。对... 对岩土参数进行传统的k-means聚类分析时,因无法确定k值,而导致无法有效剔除误差数据。为得到岩土参数可靠取值范围,基于最优k值的k-means算法进行研究,通过量化样本内距离和聚类紧密性来确定聚类数目k值,避免了传统k值的随机选取。对粉土的三个基本物理力学指标:黏聚力c、内摩擦角φ、压缩模量E_(s)进行空间聚类分析。通过比较不同k值时的E_(E)值,确定最优k值为5。聚类完成后,原样本被划分为5类子样本。样本数量最多的一类为最优子样本,这类子样本与原样本分布一致,且数量偏离程度及变异性较小。对除最优类外的其他四类子样本进行分布检验,可知A-D检验法适用于小样本,而K-S检验法适用于大样本。根据偏度系数c值,调整合适的区间长度,进一步优化参数取值范围,并与工程实际采用值对比,检验方法的可行性。该分析方法实现由小样本代替大样本进行参数统计分析求取可靠的取值区间,简化计算,提高工作效率。 展开更多
关键词 K-means 粉土 正态分布 对数正态分布 K-s检验 A-D检验
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基于D-S证据理论的岩爆预测方法研究
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作者 高永涛 朱强 +1 位作者 吴顺川 王勇兵 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期244-251,共8页
为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而... 为了有效预测岩爆,提出基于D-S证据理论的岩爆预测方法.首先,选取与岩爆发生相关的6个指标因素作为证据体,并通过模糊物元框架和正态型隶属度函数构建证据体的基本概率分配.然后,利用K均值将证据体分类,并提出簇内证据用传统方式融合而簇间证据用权重方式融合的组合融合规则,以减轻高冲突证据融合的不利影响.最后,将模型应用在秦岭终南山公路隧道2号竖井工程,且与经验方法对比.为了分析预测过程的不确定性和估计岩爆发生概率,采用蒙特卡洛模拟进行抽样仿真,并通过Spearman秩相关系数衡量输入指标的全局敏感性.研究结果表明:输入指标在不同的岩爆案例的影响程度差异较大且方向不同;5个岩爆案例的发生概率在40.8%~70.1%之间.该模型表现出优异的预测分类性能,可为深埋地下工程岩爆预测提供参考. 展开更多
关键词 岩石力学 岩爆预测 D-s证据理论 模糊物元 K均值
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经皮二氧化碳分压监测在硬质支气管镜下Feng′s EBUS-TBNB中的应用
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作者 骆玉兔 孙亚楠 +1 位作者 潘家华 万南生 《南通大学学报(医学版)》 2024年第1期45-48,共4页
目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-... 目的:探讨经皮二氧化碳分压(transcutaneous partial pressure of carbon dioxide,PtcCO_(2))监测在硬质支气管镜下冯氏气管内超声引导纵隔切开活检(Feng′s endobronchial ultrasound-guided transbronchial node biopsy,Feng′s EBUS-TBNB)中的应用。方法:收集2019年8月—2022年8月期间天津医科大学总医院收治的纵隔疾病患者128例,随机分成Feng′s EBUS-TBNB组和支气管内超声引导针吸活检术(endobronchial ultrasound-guided transbronchial needle aspiration,EBUS-TBNA)组,患者均予高频喷射通气行硬质支气管镜下操作及PtcCO_(2)监测,EBUS-TBNA组患者行EBUS-TBNA,Feng′s EBUS-TBNB组患者行Feng′s EBUS-TBNB术,比较两组患者术前(T0)、通气开始时(T_(1))、通气10 min后(T_(2))、通气20 min后(T3)、通气30 min后(T_(4))、通气40 min后(T_(5))、通气50 min后(T_(6))、通气60 min后(T_(7))心率(heart rate,HR)、平均动脉压(mean arterial pressure,MAP)和PtcCO_(2)的变化。结果:T_(1)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平均明显高于T0时(P<0.05)。T0~T_(2)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05);T3~T_(5)时,Feng′s EBUS-TBNB组HR、MAP和PtcCO_(2)水平均明显高于EBUS-TBNA组(P<0.05);而T_(6)~T_(7)时,两组患者HR、MAP和PtcCO_(2)水平比较差异无统计学意义(P>0.05)。结论:将PtcCO_(2)应用于Feng′s EBUS-TBNB中,可间接反映患者HR、MAP水平变化,值得临床推广应用。 展开更多
关键词 纵隔疾病 经皮二氧化碳分压 硬质支气管镜 冯氏气管内超声引导纵隔切开活检 心率 平均动脉压
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SHARP BOUNDS FOR TOADER-TYPE MEANS IN TERMS OF TWO-PARAMETER MEANS 被引量:2
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作者 杨月英 钱伟茂 +1 位作者 张宏伟 褚玉明 《Acta Mathematica Scientia》 SCIE CSCD 2021年第3期719-728,共10页
In the article,we prove that the double inequalities Gp[λ1a+(1-λ1)b,λ1 b+(1-λ1)a]A1-p(a,b)<T[A(a,b),G(a,b)]<Gp[μ1 a+(1-μ1)b,μ1b+(1-μ1)a]A1-p(a,b),Cs[λ^(2) a+(1-λ2)b,λ2 b+(1-λ2)a]A1-s(a,b)<T[A(a,b)... In the article,we prove that the double inequalities Gp[λ1a+(1-λ1)b,λ1 b+(1-λ1)a]A1-p(a,b)<T[A(a,b),G(a,b)]<Gp[μ1 a+(1-μ1)b,μ1b+(1-μ1)a]A1-p(a,b),Cs[λ^(2) a+(1-λ2)b,λ2 b+(1-λ2)a]A1-s(a,b)<T[A(a,b),Q(a,b)]<Cs[μ2 a+(1-μ2)b,μ2 b+(1-μ2)a]A1-p(a,b)hold for all a,b>0 with a≠b if and only ifλ1≤1/2-(1-(2/π)2/p)1/2/2,μ1≥1/2-(2p)1/2/(4 p),λ2≤1/2+(2(3/(2 s)(E(21/2/2)/π)1/s)-1)1/2/2 andμ2≥1/2+s1/2/(4 s)ifλ1,μ1∈(0,1/2),λ2,μ2∈(1/2,1),p≥1 and s≥1/2,where G(a,b)=(ab)1/2,A(a,b)=(a+b)/2,T(a,b)=∫0π/2(a2 cos2 t+b2 sin2)1/2 tdt/π,Q(a,b)=((a2+b2)/2)1/2,C(a,b)=(a2+b2)/(a+b)and E(r)=∫0π/2(1-r^(2) sin^(2))1/2 tdt. 展开更多
关键词 Geometric mean arithmetic mean toader mean ontraharmonic mean complete elliptic integral
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TOADER型平均的调和与NEUMAN平均凸组合界
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作者 何晓红 《高等数学研究》 2024年第1期25-28,112,共5页
研究了TOADER型平均和调和平均与NEUMAN平均凸组合的序关系,运用单调性L HOSPITAL法则,证明了TOADER型平均关于调和与NEUMAN平均凸组合的确界.作为应用,分别给出了第二类完全椭圆积分关于反双曲正弦和反正切函数的两个不等式.所得结果... 研究了TOADER型平均和调和平均与NEUMAN平均凸组合的序关系,运用单调性L HOSPITAL法则,证明了TOADER型平均关于调和与NEUMAN平均凸组合的确界.作为应用,分别给出了第二类完全椭圆积分关于反双曲正弦和反正切函数的两个不等式.所得结果是对一些己知结果的改进. 展开更多
关键词 完全椭圆积分 toader平均 NEUMAN平均 调和平均
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K-means与SVM结合的水下目标分类方法 被引量:7
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作者 戴冬 卫娟 《舰船科学技术》 北大核心 2015年第2期204-207,共4页
为促进海洋资源开发,提高海洋开发能力,本文对水下目标分类识别方法进行研究。首先,对水下目标分类方法进行概述,介绍较为常用的方法。然后,提出K-means与SVM结合的水下目标分类方法。该方法利用S变换进行图像预处理,提取不同分辨率下... 为促进海洋资源开发,提高海洋开发能力,本文对水下目标分类识别方法进行研究。首先,对水下目标分类方法进行概述,介绍较为常用的方法。然后,提出K-means与SVM结合的水下目标分类方法。该方法利用S变换进行图像预处理,提取不同分辨率下的不同特征作为分类的特征向量,通过K-means与SVM结合的分类识别方法进行分类。实验结果表明,该方法具有较高的识别率。 展开更多
关键词 s变换 K-means sVM
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基于改进的颜色特征和直方图更新的Mean-Shift算法 被引量:3
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作者 刘康亚 孙首群 +2 位作者 刘硕研 王冰 吕晓军 《交通运输系统工程与信息》 EI CSCD 北大核心 2012年第4期84-92,共9页
为了提高复杂环境下智能视频监控对运动目标跟踪的可靠性,提出一种基于改进的颜色特征和直方图更新的Mean-Shift跟踪算法.该算法利用像素点局部颜色变化作为跟踪目标像素点特征,弥补单一颜色值特征对目标表征的不足;并根据Mean-Shift跟... 为了提高复杂环境下智能视频监控对运动目标跟踪的可靠性,提出一种基于改进的颜色特征和直方图更新的Mean-Shift跟踪算法.该算法利用像素点局部颜色变化作为跟踪目标像素点特征,弥补单一颜色值特征对目标表征的不足;并根据Mean-Shift跟踪结果和目标匹配程度对目标直方图进行更新,保证在目标姿态和大小发生变化时目标特征直方图的有效性.实验结果表明:与传统Mean-Shift算法相比,改进的颜色特征减小了相似背景像素对运动目标的干扰,目标直方图的更新提高了Mean-Shift算法对目标姿态和大小改变的鲁棒性.算法提高了基于颜色特征的Mean-Shift算法对复杂环境中运动目标进行实时跟踪的可靠性. 展开更多
关键词 智能交通 运动目标跟踪 mean-sHIFT算法 运动目标 颜色分布特征 直方图更新
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基于mean-shift全局立体匹配方法 被引量:3
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作者 王召月 陈丽芳 《计算机工程与科学》 CSCD 北大核心 2017年第7期1333-1337,共5页
针对图像全局立体匹配精度高、计算量大的问题,提出基于mean shift图像分割的全局立体匹配方法。首先,通过mean shift算法对图像进行分割,获取图像同质区域数量和区域的标号。在计算匹配代价时,根据像素所属的分割区域,对像素进行筛选,... 针对图像全局立体匹配精度高、计算量大的问题,提出基于mean shift图像分割的全局立体匹配方法。首先,通过mean shift算法对图像进行分割,获取图像同质区域数量和区域的标号。在计算匹配代价时,根据像素所属的分割区域,对像素进行筛选,从而提高匹配代价计算速度;其次,在代价聚合前,将mean shift算法获取的同质区域数K值赋值给K-means聚类算法,对像素再次聚类,提高立体匹配精度和速度;最后通过TRW-S置信传播解决能量最小化问题。实验表明,该算法明显提高了匹配的准确性和速度,与单纯的全局匹配算法相比,具有更大的优势。 展开更多
关键词 立体匹配 mean shift分割 TRW-s置信传播
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THE OPTIMAL GENERALIZED LOGARITHMIC MEAN BOUNDS FOR SEIFFERT'S MEAN 被引量:3
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作者 褚玉明 王淼坤 王根娣 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1619-1626,共8页
For p ∈ R, the generalized logarithmic mean Lp(a, b) and Seiffert's mean T(a, b) of two positive real numbers a and b are defined in (1.1) and (1.2) below respectively. In this paper, we find the greatest p ... For p ∈ R, the generalized logarithmic mean Lp(a, b) and Seiffert's mean T(a, b) of two positive real numbers a and b are defined in (1.1) and (1.2) below respectively. In this paper, we find the greatest p and least q such that the double-inequality Lp(a, b) 〈 T(a,b) 〈 Lq(a,b) holds for all a,b 〉 0 and a ≠ b. 展开更多
关键词 generalized logarithmic mean seiffert's mean power mean
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SOME INTEGRAL MEAN ESTIMATES FOR POLYNOMIALS 被引量:1
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作者 A. Aziz W. M. Shah 《Analysis in Theory and Applications》 2007年第2期101-111,共11页
In this paper we establish L^q inequalities for polynomials, which in particular yields interesting generalizations of some Zygmund-type inequalities.
关键词 POLYNOMIAL Bernstein's inequality L^q mean estimate zero
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Detecting dopaminergic neuronal degeneration using diffusion tensor imaging in a rotenone-induced rat model of Parkinson's disease: fractional anisotropy and mean diffusivity values 被引量:1
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作者 Lan-xiang Liu Dan Du +6 位作者 Tao Zheng Yuan Fang Yan-sheng Chen Hui-ling Yi Qing-yuan He Da-wei Gao Qing-lei Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第9期1485-1491,共7页
Dopamine content in the basal ganglia is strongly associated with the degree of dopaminergic neuron loss in the substantia nigra pars com- pacta. Symptoms of Parkinson's disease might not arise until more than 50% of... Dopamine content in the basal ganglia is strongly associated with the degree of dopaminergic neuron loss in the substantia nigra pars com- pacta. Symptoms of Parkinson's disease might not arise until more than 50% of the substantia nigra pars compacta is lost and the dopamine content in the basal ganglia is reduced by more than 80%. Greater diagnostic sensitivity and specificity would allow earlier detection of Parkinson's disease. Diffusion tensor imaging is a recently developed magnetic resonance imaging technique that measures mean diffusiv- ity and fractional anisotropy, and responds to changes in brain microstructure. When the microscopic barrier (including cell membranes, microtubules and other structures that interfere with the free diffusion of water) is destroyed and extracellular fluid volume accumulates, the mean diffusivity value increases; when the integrity of the microstructure (such as myelin) is destroyed, fractional anisotropy value decreases. However, there is no consensus as to whether these changes can reflect the early pathological alterations in Parkinson's disease. Here, we established a rat model of Parkinson's disease by injecting rotenone (or sunflower oil in controls) into the right suhstantia nigra. Diffusion tensor imaging results revealed that in the stages of disease, at 1, 2, 4, and 6 weeks after rotenone injection, fiactional anisotropy value decreased, but mean diffusivity values increased in the right substantia nigra in the experimental group. Fractional anisotropy values were lower at 4 weeks than at 6 weeks in the right substantia nigra of rats from the experimental group. Mean diffusivity values were mark- edly greater at 1 week than at 6 weeks in the right corpus striatum of rats from the experimental group. These findings suggest that mean diffusivity and fractional anisotropy values in the brain of rat models of Parkinson's disease 4 weeks after model establishment can reflect early degeneration of dopaminergic neurons. 'The change in fractional anisotropy values after destruction of myelin integrity is likely to be of greater early diagnostic significance than the change in mean diffusivity values. 展开更多
关键词 nerve regeneration diffusion tensor imaging fractional anisotropy mean diffusivity magnetic resonance imaging Parkinson's disease ROTENONE neurodegenerative disease biomarkers substantia nigra tyrosine hydroxylase neural regeneration
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基于S变换和k-means聚类的输电线路故障识别 被引量:2
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作者 周郑 郭丽娜 《黄河水利职业技术学院学报》 2021年第1期45-50,共6页
根据正常电路和故障电路特征电流存在的差异,提出基于S变换和k-means聚类的输电线路故障识别方法。通过S变换的方式,获取线路特征电流的故障特征量,应用熵权法计算出变换综合相对熵,找出线路之间的差异。然后,使用k-means聚类的方法识... 根据正常电路和故障电路特征电流存在的差异,提出基于S变换和k-means聚类的输电线路故障识别方法。通过S变换的方式,获取线路特征电流的故障特征量,应用熵权法计算出变换综合相对熵,找出线路之间的差异。然后,使用k-means聚类的方法识别出故障线路。通过仿真试验验证,该故障识别方法准确率较高、适应性强。 展开更多
关键词 输电线路 故障识别 s变换 综合相对熵 K-means聚类 仿真试验
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A simplified two-dimensional boundary element method with arbitrary uniform mean flow 被引量:2
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作者 Bassem Barhoumi Safa Ben Hamouda Jamel Bessrour 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2017年第4期207-221,共15页
To reduce computational costs, an improved form of the frequency domain boundary element method(BEM) is proposed for two-dimensional radiation and propagation acoustic problems in a subsonic uniform flow with arbitr... To reduce computational costs, an improved form of the frequency domain boundary element method(BEM) is proposed for two-dimensional radiation and propagation acoustic problems in a subsonic uniform flow with arbitrary orientation. The boundary integral equation(BIE) representation solves the two-dimensional convected Helmholtz equation(CHE) and its fundamental solution, which must satisfy a new Sommerfeld radiation condition(SRC) in the physical space. In order to facilitate conventional formulations, the variables of the advanced form are expressed only in terms of the acoustic pressure as well as its normal and tangential derivatives, and their multiplication operators are based on the convected Green's kernel and its modified derivative. The proposed approach significantly reduces the CPU times of classical computational codes for modeling acoustic domains with arbitrary mean flow. It is validated by a comparison with the analytical solutions for the sound radiation problems of monopole,dipole and quadrupole sources in the presence of a subsonic uniform flow with arbitrary orientation. 展开更多
关键词 Two-dimensional convected Helmholtz equation Two-dimensional convected Green’s function Two-dimensional convected boundary element method Arbitrary uniform mean flow Two-dimensional acoustic sources
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Mass Constituents of a Flat Lattice Multiverse: Conclusion from Similarity between Two Universal Numbers, the Rocksalt-Type 2<i>D</i>Madelung Constant and the Golden Mean 被引量:2
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作者 Hans Hermann Otto 《Journal of Modern Physics》 2018年第1期1-13,共13页
In fairly good agreement with the consensus range of dark energy to matter this ratio of the critical density is suggested to be connected with the golden mean &phi;=0.6180339887, yielding for dark energy to matte... In fairly good agreement with the consensus range of dark energy to matter this ratio of the critical density is suggested to be connected with the golden mean &phi;=0.6180339887, yielding for dark energy to matter mass fractions .?Assuming the baryonic matter to be only 4.432%, the ratio of matter to baryonic matter would be , and further the ratio of dark matter to baryonic one . If one subtracts from the dark matter a contribution of antimatter with the same mass of baryonic matter, according to the antigravity theories of Villata respectively Hajdukovic, the remaining mass ratio would yield . Replacing the “Madelung” constant α of Villata’s “lattice universe” by &phi;, one reaches again 1 + &phi;as the ratio of the repulsive mass contribution to the attractive one. Assuming instead of a 3D lattice a flat 2D one of rocksalt type, the numerical similarity between the Madelung constant and φ&minus;1 could not be just coincidence. The proposed scaling of the cosmological mass fractions with the square of the most irrational universal number &phi;may indicate that the chaotic cosmological processes have reached a quite stable equilibrium. This may be confirmed by another, but similar representation of the mass constituents by the Archimedes’ constant &pi;, giving for respectively for the dark components . However, the intimate connection of φ with its reciprocal may ignite the discussion whether our universe is intertwined with another universe or even part of a multiverse with the dark constituents contributed from there. 展开更多
关键词 UNIVERsAL NUMBERs Fractal NUMBERs Golden mean Archimedes CONsTANT Fibonacci NUMBERs Madelung Constants sommerfeld’s Fine structure CONsTANT Euler Number LATTICE UNIVERsE Reciprocal UNIVERsE Cosmological MAss Fractions Hubble CONsTANT Gyromagnetic Factor
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Random Crank-Nicolson Scheme for Random Heat Equation in Mean Square Sense 被引量:1
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作者 M. T. Yassen M. A. Sohaly Islam Elbaz 《American Journal of Computational Mathematics》 2016年第2期66-73,共8页
The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for s... The goal of computational science is to develop models that predict phenomena observed in nature. However, these models are often based on parameters that are uncertain. In recent decades, main numerical methods for solving SPDEs have been used such as, finite difference and finite element schemes [1]-[5]. Also, some practical techniques like the method of lines for boundary value problems have been applied to the linear stochastic partial differential equations, and the outcomes of these approaches have been experimented numerically [7]. In [8]-[10], the author discussed mean square convergent finite difference method for solving some random partial differential equations. Random numerical techniques for both ordinary and partial random differential equations are treated in [4] [10]. As regards applications using explicit analytic solutions or numerical methods, a few results may be found in [5] [6] [11]. This article focuses on solving random heat equation by using Crank-Nicol- son technique under mean square sense and it is organized as follows. In Section 2, the mean square calculus preliminaries that will be required throughout the paper are presented. In Section 3, the Crank-Nicolson scheme for solving the random heat equation is presented. In Section 4, some case studies are showed. Short conclusions are cleared in the end section. 展开更多
关键词 Random Partial Differential Equations (RPDEs) mean square sense (m.s) second Order Random Variable (2r.v.'s) Random Crank-Nicolson scheme CONVERGENCE CONsIsTENCY stability
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Implicit Continuous User Authentication for Mobile Devices based on Deep Reinforcement Learning 被引量:1
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作者 Christy James Jose M.S.Rajasree 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1357-1372,共16页
The predominant method for smart phone accessing is confined to methods directing the authentication by means of Point-of-Entry that heavily depend on physiological biometrics like,fingerprint or face.Implicit continuou... The predominant method for smart phone accessing is confined to methods directing the authentication by means of Point-of-Entry that heavily depend on physiological biometrics like,fingerprint or face.Implicit continuous authentication initiating to be loftier to conventional authentication mechanisms by continuously confirming users’identities on continuing basis and mark the instant at which an illegitimate hacker grasps dominance of the session.However,divergent issues remain unaddressed.This research aims to investigate the power of Deep Reinforcement Learning technique to implicit continuous authentication for mobile devices using a method called,Gaussian Weighted Cauchy Kriging-based Continuous Czekanowski’s(GWCK-CC).First,a Gaussian Weighted Non-local Mean Filter Preprocessing model is applied for reducing the noise pre-sent in the raw input face images.Cauchy Kriging Regression function is employed to reduce the dimensionality.Finally,Continuous Czekanowski’s Clas-sification is utilized for proficient classification between the genuine user and attacker.By this way,the proposed GWCK-CC method achieves accurate authen-tication with minimum error rate and time.Experimental assessment of the pro-posed GWCK-CC method and existing methods are carried out with different factors by using UMDAA-02 Face Dataset.The results confirm that the proposed GWCK-CC method enhances authentication accuracy,by 9%,reduces the authen-tication time,and error rate by 44%,and 43%as compared to the existing methods. 展开更多
关键词 Deep reinforcement learning gaussian weighted non-local meanfilter cauchy kriging regression continuous czekanowski’s implicit continuous authentication mobile devices
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2021年玛多M_(S)7.4地震与2010年玉树M_(S)7.1地震前频谱特征分析
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作者 余娜 孙玺皓 张晓清 《地震》 CSCD 北大核心 2023年第3期150-158,共9页
为进一步验证和完善使用频带变窄且向低频段偏移特征识别前震的判定依据,本文基于青海、甘肃等区域数字化测震台网记录的波形数据,对比分析2021年玛多7.4级地震前148 d发生的2020年12月24日玛多4.2级地震与2010年4月14日玉树7.1级地震前... 为进一步验证和完善使用频带变窄且向低频段偏移特征识别前震的判定依据,本文基于青海、甘肃等区域数字化测震台网记录的波形数据,对比分析2021年玛多7.4级地震前148 d发生的2020年12月24日玛多4.2级地震与2010年4月14日玉树7.1级地震前的4.7级地震快速傅里叶变换的频谱特征。结果显示,玛多4.2级地震频谱的频段较宽,优势频段为0~5.0 Hz,玉树4.7级地震频谱的频带变窄且向低频端偏移的特征较为显著,优势频段为0~1.5 Hz。对比分析认为,“频带变窄且向低频偏移”现象对识别直接前震有较好的效果,需重点关注中小地震出现频谱偏移后短期内(1~3个月)震源区附近强震发生的可能性。 展开更多
关键词 直接前震 FFT均方谱 2010年玉树4.7级地震 2020年玛多4.2级地震
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Re-Formulation of Mean King’s Problem Using Shannon’s Entropy
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作者 Masakazu Yoshida Hideki Imai 《Journal of Quantum Information Science》 2013年第1期6-9,共4页
Mean King’s problem is formulated as a retrodiction problem among noncommutative observables. In this paper, we reformulate Mean King’s problem using Shannon’s entropy as a first step of introducing quantum uncerta... Mean King’s problem is formulated as a retrodiction problem among noncommutative observables. In this paper, we reformulate Mean King’s problem using Shannon’s entropy as a first step of introducing quantum uncertainty relation with delayed classical information. As a result, we give informational and statistical meanings to the estimation on Mean King problem. As its application, we give an alternative proof of nonexistence of solutions of Mean King’s problem for qubit system without using entanglement. 展开更多
关键词 mean King’s PROBLEM QUANTUM Retrodiction PROBLEM QUANTUM Estimation PROBLEM shannon’s ENTROPY
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Faith and Meaning:A Study of the Chinese Translation of Shakespeare’s Midsummer Night’s Dream by Liang Shiqiu from the Perspective of Topology
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作者 YANG Fei-ran 《Journal of Literature and Art Studies》 2022年第9期882-890,共9页
Topology,as a branch of mathematics,studies on the invariability of topological spaces after topological transformation,whose essence is topological equivalence.From the perspective of cultural inheritance and coheren... Topology,as a branch of mathematics,studies on the invariability of topological spaces after topological transformation,whose essence is topological equivalence.From the perspective of cultural inheritance and coherence,translation is essentially topological deformation.In literary translation,complete equivalence is almost impossible.Topological equivalence can be used to transform the text dynamically,which means that the translation remains the fundamental properties of the original text.Therefore,people can understand the meaning of the text based on another culture from different cultural backgrounds.From the view point of topology,the present paper purports to examine Liang Shiqiu’s translation of Shakespeare’s Midsummer Night’s Dream,and found that the translation remains the features of source text by rendering effective topological strategies to realize topological equivalence and promote cultural exchanges between China and the West. 展开更多
关键词 FAITH meanING sHAKEsPEARE A Midsummer Night’s Dream Liang shiqiu TOPOLOGY
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Protection of Women's Rights Means Human Rights Protection——Marking the 30th anniversary of the Convention on the Elimination of All Forms of Discrimination against Women 被引量:1
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作者 LIU BOHONG deputy director of the Research Institute for Women under the All-China Women’s Federation 《The Journal of Human Rights》 2010年第2期4-7,共4页
On December 18, 1979, the 34th General Assembly of the United Nations adopted the Convention on the Elimination of All Forms of Discrimination against Women with an overwhelming majority of the votes in its favor. Ove... On December 18, 1979, the 34th General Assembly of the United Nations adopted the Convention on the Elimination of All Forms of Discrimination against Women with an overwhelming majority of the votes in its favor. Over the past 30 years, the Convention has come to be known by increasing numbers of governments and people, particularly women's organizations. It has played an increasingly great role in protecting women's rights and enhancing women's status in society. 展开更多
关键词 Protection of Women’s Rights means Human Rights Protection Marking the 30th anniversary of the Convention on the Elimination of All Forms of Discrimination against Women
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