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The empirical relationships between M_S,m_band M_L for China and vicinity
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作者 杨智娴 张培震 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期9-16,共8页
IntroductionMeasuringthesizeofanearthquakeusingauniformscaleisveryimportantinseismichazardasesment,earthquak... IntroductionMeasuringthesizeofanearthquakeusingauniformscaleisveryimportantinseismichazardasesment,earthquakeprediction,andb... 展开更多
关键词 MAGNITUDE empirical RELATION uncertainty complementary cumulative distribution function
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Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families
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作者 李金平 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期20-22,共3页
In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0&... In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞. 展开更多
关键词 one-side truncation distribution families absolute error loss function empirical Bayes estimator convergence rates
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The Cox-Aalen Models as Framework for Construction of Bivariate Probability Distributions, Universal Representation 被引量:1
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作者 Jerzy K. Filus 《Journal of Statistical Science and Application》 2017年第2期56-63,共8页
Starting with the Aalen (1989) version of Cox (1972) 'regression model' we show the method for construction of "any" joint survival function given marginal survival functions. Basically, however, we restrict o... Starting with the Aalen (1989) version of Cox (1972) 'regression model' we show the method for construction of "any" joint survival function given marginal survival functions. Basically, however, we restrict ourselves to model positive stochastic dependences only with the general assumption that the underlying two marginal random variables are centered on the set of nonnegative real values. With only these assumptions we obtain nice general characterization of bivariate probability distributions that may play similar role as the copula methodology. Examples of reliability and biomedical applications are given. 展开更多
关键词 Cox model Aalen additive hazards model construction of bivariate probability distributions givenmarginal distributions "joiner" as dependence function "connecting" the marginals general characterization ofbivariate distributions similarity to the copula methodology reliability and biomedical applications
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IMPACT OF CLIMATE ON GRAIN YIELD PER UNIT AREA IN CHINA DURING THE YEARS OF 1949~1992
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作者 谢云 刘继东 《Chinese Geographical Science》 SCIE CSCD 1998年第4期22-29,共8页
The grain yield per unit area in China has been increasing from 1949 to 1992 with annual fluctuations, which was caused by both policies and monsoon climate. The total grain yield is divided into trend yield, which r... The grain yield per unit area in China has been increasing from 1949 to 1992 with annual fluctuations, which was caused by both policies and monsoon climate. The total grain yield is divided into trend yield, which reflects the influence of economic factors, and climate yield, which reflects the impact of climate factors. The results of grain and climate yield by EOF (empirical orthogonal function) method show that the grain yield in the eastern China is higher and more fluctuating than that in the western region. The spatial and temporal distributions of climate yield were divided into four patterns. Regional unanimity of climate yield variation is the first and main spatial pattern, and then there are the spatial patterns of north-south difference and east-west difference in some years. Generally, climate conditions are good for grain yield during the 1950s and 1980s all over the country. 展开更多
关键词 GRAin YIELD CLIMATE YIELD empirical ORTHOGONAL function spatial and TEMPORAL distribution
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High Moments Jarque-Bera Tests for Arbitrary Distribution Functions
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作者 Gane Samb Lo Oumar Thiam Mohamed Cheikh Haidara 《Applied Mathematics》 2015年第4期707-716,共10页
The Jarque-Bera’s fitting test for normality is a celebrated and powerful one. In this paper, we consider general Jarque-Bera tests for any distribution function (df) having at least 4k finite moments for k ≥ 2. The... The Jarque-Bera’s fitting test for normality is a celebrated and powerful one. In this paper, we consider general Jarque-Bera tests for any distribution function (df) having at least 4k finite moments for k ≥ 2. The tests use as many moments as possible whereas the JB classical test is supposed to test only skewness and kurtosis for normal variates. But our results unveil the relations between the coeffients in the JB classical test and the moments, showing that it really depends on the first eight moments. This is a new explanation for the powerfulness of such tests. General Chi-square tests for an arbitrary model, not only normal, are also derived. We make use of the modern functional empirical processes approach that makes it easier to handle statistics based on the high moments and allows the generalization of the JB test both in the number of involved moments and in the underlying distribution. Simulation studies are provided and comparison cases with the Kolmogorov-Smirnov’s tests and the classical JB test are given. 展开更多
关键词 ASYMPTOTIC distribution ASYMPTOTIC STATISTICAL TESTS NORMALITY TESTS functional empirical Processes
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Strong Convergence of Empirical Distribution for a Class of Random Matrices
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作者 LIANG Qing-wen MIAO Bai-qi WANG Da-peng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期28-32,共5页
Let {vij}, i, j = 1, 2, …, be i.i.d, random variables with Ev11 = 0, Ev11^2 = 1 and a1 = (ai1,…, aiM) be random vectors with {aij} being i.i.d, random variables. Define XN =(x1,…, xk) and SN =XNXN^T,where xi=ai... Let {vij}, i, j = 1, 2, …, be i.i.d, random variables with Ev11 = 0, Ev11^2 = 1 and a1 = (ai1,…, aiM) be random vectors with {aij} being i.i.d, random variables. Define XN =(x1,…, xk) and SN =XNXN^T,where xi=ai×si and si=1/√N(v1i,…, vN,i)^T. The spectral distribution of SN is proven to converge, with probability one, to a nonrandom distribution function under mild conditions. 展开更多
关键词 empirical spectral distribution function sample covariance matrix Stieltjes transform strong convergence
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On the Power Performance of Test Statistics for the Generalized Rayleigh Interval Grouped Data
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作者 Hatim Solayman Migdadi 《Open Journal of Statistics》 2015年第5期474-482,共9页
In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulati... In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulation process is conducted to evaluate their controlling of type 1 error and their power functions. Generally, the weighted Kolmogrov-Smirnov test statistics show a relatively better performance than both, the Cramer von-Miss and the Anderson Darling test statistics. For large sample values, the Anderson Darling test statistics cannot control type 1 error but for relatively small sample values it indicates a better performance than the Cramer von-Miss test statistics. Best selection of the test statistics and highlights for future studies are also explored. 展开更多
关键词 GENERALIZED RAYLEIGH distribution inTERVAL Grouped Data GOODNESS of FIT Tests empirical Type 1 ERROR Power function
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Liminf law of the iterated logarithm for the smooth empirical distribution function
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作者 周勇 《Chinese Science Bulletin》 SCIE EI CAS 1996年第3期185-189,共5页
The study of perturbed (smoothed) empirical distribution has received considerable at-tention. The monograph by Reiss gives a particularly lucid exposition of the mathematical attractions of smoothing the empirical di... The study of perturbed (smoothed) empirical distribution has received considerable at-tention. The monograph by Reiss gives a particularly lucid exposition of the mathematical attractions of smoothing the empirical distribution function (e.d.f.): it is intuitively appealing; it is easy to compute, it provides increased second-order efficiency (see refs. [2, 3]) and it improves the speed of convergence in Bootstrap (see refs. [4,5]). 展开更多
关键词 liminf LAW of ITERATED LOGARITHM SMOOTH empirical distribution function.
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Asymptotic Normality of the Empirical Distribution under Negatively Associated Sequences and its Applications
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作者 李永明 杨善朝 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第3期457-464,共8页
By the well-known large and small blocks parting method for dependent situations, we establish the asymptotic normality of the Empirical Distribution Function under Negatively Associated Sequences. As its application ... By the well-known large and small blocks parting method for dependent situations, we establish the asymptotic normality of the Empirical Distribution Function under Negatively Associated Sequences. As its application in reliablity problems, a natural estimate Fn(x) for the survival function F(x) = P(X 〉 x) is proposed, and the asymptotic normality of n^1/2 [Fn(x) - F(x)] is established. 展开更多
关键词 NA sequences empirical distribution survival function asymptotic normality.
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复合LINEX对称损失下逆威布尔分布尺度参数的E-Bayes估计 被引量:5
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作者 仲崇刚 韦程东 吕孝亮 《广西师范学院学报(自然科学版)》 2011年第4期37-38,50,共3页
在统计决策问题中,统计决策及参数估计的优劣性在很大程度上依赖于损失函数形式的选取.该文在复合LINEX对称损失函数下,求出先验分布为Γ分布,逆威布尔分布尺度参数θ的E-Bayes估计.
关键词 逆威布尔分布 复合LinEX对称损失函数 E-BAYES估计
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Meso-Zeaxanthin:One of Important Carotenoids for Human Health 被引量:1
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作者 XU Xinde JIANG Lianzhou +1 位作者 ZHANG Lihua SHAO Bin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第3期76-81,共6页
As one of optical isomers of zeaxanthin, meso-zeaxanthin is an important ingredient of macular pigment. Compared with lutein and zeaxanthin, meso-zeaxanthin may display strong functions as antioxidant and filtering sh... As one of optical isomers of zeaxanthin, meso-zeaxanthin is an important ingredient of macular pigment. Compared with lutein and zeaxanthin, meso-zeaxanthin may display strong functions as antioxidant and filtering short-wavelength, for example, the blue light. Comparisons among lutein, zeaxanthin and meso-zeaxanthin as well as functions and distributions together with the source of meso-zeaxanthin were discussed. The application as a supplement of diet and issues should be studied in the future for mesozeaxanthin were also analyzed. 展开更多
关键词 meso-zeaxanthin function distribution SOURCE application
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ASYMPTOTICS FOR THE DISTRIBUTION FUNCTION ESTIMATORS OF THE ERRORS IN SEMI-PARAMETRIC REGRESSION MODELS
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作者 QIU Yuyang FU Keang HUANG Wei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2014年第2期360-369,共10页
This paper considers the convergence rates for nonparametric estimators of the error distribution in semi-parametric regression models. By establishing some general laws of the iterated logarithm, it shows that the ra... This paper considers the convergence rates for nonparametric estimators of the error distribution in semi-parametric regression models. By establishing some general laws of the iterated logarithm, it shows that the rates of convergence of either the empirical distribution or a smoothed version of the empirical distribution function matches exactly the rates obtained for an independent sample from the error distribution. 展开更多
关键词 empirical distribution function kernel distribution function law of the iterated loga-rithm semi-parametric regression model residuals.
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MICROCOMPUTERIZED MEASUREMENT AND ANALYSIS OF ELECTRON EMISSION PROPERTIES OF THERMIONIC CATHODES
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作者 曾海山 杨凌云 叶毓林 《Journal of Electronics(China)》 1989年第3期272-281,共10页
A microcomputerized measurement system is developed.This system automatically acquiresan I-V characteristic curve in 5 seconds with the accuracy of 0.05% FSR(full scale range).The Schottkyextrapolation field-free emi... A microcomputerized measurement system is developed.This system automatically acquiresan I-V characteristic curve in 5 seconds with the accuracy of 0.05% FSR(full scale range).The Schottkyextrapolation field-free emission,the inflection-point emission,the flection-point emission,the average effec-tive work function.the Richardson work function,the work function distribution at the operation tempera-ture and other important information that reflects properties of cathodes are obtained by this system.The re-sults of analysing four types of cathodes demonstrate that this system is very suitable for measuring the activi-ty changes of the cathode in the processes of activation,ageing,poisoning and life test.It is proved that thissystem can also be used to monitor the actlvity of the cathode in the assembled tube by measuring a gridcontrolled travelling-wave tube. 展开更多
关键词 thermionic CATHODE Measurement of thermionic EMISSION properties WORK function distribution inflection-point EMISSION Flection-point EMISSION application of MICROCOMPUTER
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Spatial and Temporal Variations of Climate in Europe
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作者 Vladimir Kossobokov Jean-Louis Le Mouel Claude Allègre 《Atmospheric and Climate Sciences》 2012年第4期568-581,共14页
Temperature series of the original individual measurements of the minimum and maximum daily temperatures from 24 stations located in different regions of Europe are considered with the objective of studying the stabil... Temperature series of the original individual measurements of the minimum and maximum daily temperatures from 24 stations located in different regions of Europe are considered with the objective of studying the stability or the variability of the “climate” in time and space. The patterns of the temperature statistics, the shapes of probability density functions, in particular, at different places and times allow comparisons based on the Kolmogorov-Smirnov test, the Shannon entropy, and cluster analysis, used separately or in combination for the purposes of quantitative climate classification. 展开更多
关键词 Daily Air Temperature CLIMATE CLASSIFICATION empirical distribution function ENTROPY Cluster Analysis
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基于EOF-DBSCAN-GRU的分布式光伏集群出力预测方法研究 被引量:2
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作者 麻吕斌 潘国兵 +3 位作者 蒋群 郭鹏 吴春华 赵宇航 《太阳能学报》 EI CAS CSCD 北大核心 2024年第1期39-46,共8页
提出一种基于EOF-DBSCAN划分集群的改进统计升尺度的光伏集群出力预测建模方法。针对传统统计升尺度方法子集群中光伏电站出力特性不一致问题,通过皮尔逊相关系数和经验正交函数(EOF)优化特征空间,再根据密度聚类模型(DBSCAN)对区域内... 提出一种基于EOF-DBSCAN划分集群的改进统计升尺度的光伏集群出力预测建模方法。针对传统统计升尺度方法子集群中光伏电站出力特性不一致问题,通过皮尔逊相关系数和经验正交函数(EOF)优化特征空间,再根据密度聚类模型(DBSCAN)对区域内光伏电站划分集群,从而增强光伏电站聚类后集群出力特性的一致性。针对待预测日权重系数时间序列动态特性的提取、预测问题,提出一种基于动态时间规整(DTW)的相似日选取算法。最后利用循环神经网络(GRU)模型进行光伏电站出力预测。实验表明该集群预测方法的平均误差百分数(MAPE)约为6.33%,均方根误差(RMSE)约为13.93 kW,均方误差(MSE)为194.25 kW,通过实际光伏电站数据证明了所提方法的准确性和有效性。 展开更多
关键词 分布式光伏电站 集群划分 经验正交函数 DBSCAN聚类算法 动态时间规整
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1961—2020年黄河源区降水时空变化特征研究
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作者 严昌盛 王鹏 +3 位作者 靳莉君 刘静 轩党委 张荣刚 《水文》 CSCD 北大核心 2024年第5期84-91,共8页
基于1961—2020年黄河源区16个雨量站点的逐日降水资料,应用线性趋势法、Mann-Kendall(MK)检验、滑动t检验、Pettitt检验、小波分析、经验正交分解(EOF)方法对黄河源区年降水、季节降水、汛期降水的变化趋势及时空分布特征进行分析。结... 基于1961—2020年黄河源区16个雨量站点的逐日降水资料,应用线性趋势法、Mann-Kendall(MK)检验、滑动t检验、Pettitt检验、小波分析、经验正交分解(EOF)方法对黄河源区年降水、季节降水、汛期降水的变化趋势及时空分布特征进行分析。结果表明:(1)黄河源区年降水以10.0 mm/10 a的趋势显著增加;除冬季呈不明显的减少趋势外,春季、夏季、秋季和汛期降水同样呈增加趋势。(2)黄河源区降水除春季无明显突变外,全年、夏季、秋季、冬季和汛期的对应突变年份分别为2015年、1998年、2018年、2016年和2019年。(3)黄河源区年降水存在3~7 a、6~12 a、9~13 a和16~24 a的变化周期,第一、第二主周期为19 a和11 a,两种主周期都经历了3次“丰-枯”变化;年降水存在2种模态,4种降水表现类型,2种模态的年份数为35 a和13 a。研究成果可为黄河源区防汛抗旱及上游水库群水资源调度提供参考。 展开更多
关键词 MANN-KENDALL检验 时空分布 黄河源区 小波分析 经验正交分解
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扩展帝国竞争算法求解分布式不相关并行机车间调度问题
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作者 李立山 陶翼飞 +2 位作者 何毅 周国诚 王镜捷 《计算机应用研究》 CSCD 北大核心 2024年第9期2758-2765,共8页
针对考虑加工约束的分布式不相关并行机车间调度问题,以总运输成本、工厂间并行机齐停评价函数和工件种类平均切换次数均衡评价函数为优化目标,提出一种扩展帝国竞争算法进行求解。该算法在原始帝国竞争算法的基础上,增加了适于工厂分... 针对考虑加工约束的分布式不相关并行机车间调度问题,以总运输成本、工厂间并行机齐停评价函数和工件种类平均切换次数均衡评价函数为优化目标,提出一种扩展帝国竞争算法进行求解。该算法在原始帝国竞争算法的基础上,增加了适于工厂分配的初始化工厂-工件序列群;根据传统帝国竞争算法容易陷入局部最优的缺点,将较劣序列同化分为了外部同化机制和内部同化机制,采用局部和全局相结合的搜索方式实现扩展帝国竞争算法的智能搜索行为;采用部分匹配交叉和单点变异更新工厂-工件序列群,保证工厂-工件序列的多样性。最后设计3个不同规模12个算例,通过仿真实验验证所提算法的有效性,同时对比相关领域研究成果验证了该算法在求解分布式多目标不相关并行机调度问题方面的优越性。 展开更多
关键词 扩展帝国竞争算法 分布式不相关并行机车间调度问题 总运输成本 工厂间并行机齐停评价函数 工厂间工件种类平均切换次数均衡评价函数
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基于同构化角度的离群检测方法
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作者 裴正中 赵旭俊 《计算机工程与设计》 北大核心 2024年第12期3622-3630,共9页
针对基于角度的离群检测方法普遍存在的计算成本高昂,且对超参数选择依赖性强的问题,提出一种基于角度的快速非参数方法HAOD。对数据集进行中心化处理并使用极坐标描;在此基础上,提出一种向量夹角计算函数的近似表示方法,采用该方法将... 针对基于角度的离群检测方法普遍存在的计算成本高昂,且对超参数选择依赖性强的问题,提出一种基于角度的快速非参数方法HAOD。对数据集进行中心化处理并使用极坐标描;在此基础上,提出一种向量夹角计算函数的近似表示方法,采用该方法将向量夹角用一维顺序结构表示,提升检测效率;引入经验累积分布函数分别计算向量夹角及向量模长的尾部概率,将其作为单维度尾部得分;改进单维度尾部得分的聚合方式,对原始向量及其反转向量的尾部得分进行聚合,获取最终离群得分。在ODDS和UCI高维数据集上进行实验,其结果表明,HAOD在检测效率上优于5种对比方法,分别平均提高了28.74%至84.71%。 展开更多
关键词 高维数据 离群检测 基于角度 数据同构化 极坐标表示 经验累积分布函数 偏度
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On nonparametric change point estimator based on empirical characteristic functions 被引量:3
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作者 TAN ChangChun SHI XiaoPing +1 位作者 SUN XiaoYing WU YueHua 《Science China Mathematics》 SCIE CSCD 2016年第12期2463-2484,共22页
We propose a nonparametric change point estimator in the distributions of a sequence of independent observations in terms of the test statistics given by Huˇskov′a and Meintanis(2006) that are based on weighted empi... We propose a nonparametric change point estimator in the distributions of a sequence of independent observations in terms of the test statistics given by Huˇskov′a and Meintanis(2006) that are based on weighted empirical characteristic functions. The weight function ω(t; a) under consideration includes the two weight functions from Huˇskov′a and Meintanis(2006) plus the weight function used by Matteson and James(2014),where a is a tuning parameter. Under the local alternative hypothesis, we establish the consistency, convergence rate, and asymptotic distribution of this change point estimator which is the maxima of a two-side Brownian motion with a drift. Since the performance of the change point estimator depends on a in use, we thus propose an algorithm for choosing an appropriate value of a, denoted by a_s which is also justified. Our simulation study shows that the change point estimate obtained by using a_s has a satisfactory performance. We also apply our method to a real dataset. 展开更多
关键词 change point estimator empirical characteristic function tuning parameter convergence rate asymptotic distribution
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太行山地区1973—2022年暴雨时空演变特征分析
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作者 唐倩玉 李远航 +5 位作者 胡孟然 张基恒 李华勇 傅志远 黄上玉 李依霖 《信阳师范学院学报(自然科学版)》 CAS 2024年第4期524-531,共8页
基于太行山地区13个气象站点50 a的逐日降水数据,使用Mann-Kendall突变检验、信噪比检验、Sen’s斜率估计、小波分析法、正交函数分解等方法,对太行山地区的暴雨时空演变规律进行了研究。结果表明:(1)太行山地区年暴雨量波动幅度较大,... 基于太行山地区13个气象站点50 a的逐日降水数据,使用Mann-Kendall突变检验、信噪比检验、Sen’s斜率估计、小波分析法、正交函数分解等方法,对太行山地区的暴雨时空演变规律进行了研究。结果表明:(1)太行山地区年暴雨量波动幅度较大,根据拟合斜率和Sen’s斜率估计法的结果可知,太行山地区的暴雨量将会呈增多趋势;(2)Mann-Kendall突变检验和信噪比检验结果表明,2006年太行山暴雨量发生了由少变多的突变;(3)Morlet小波分析结果表明,在2017—2020间研究区暴雨量存在2~3 a的周期尺度变换;(4)该地区暴雨量经验正交函数(EOF)展开的前两个模态显示,暴雨量呈现全区一致变化以及西南—东北向的空间变化特征,这两个模态情境下的暴雨状况受到环流因子和地形的共同影响。 展开更多
关键词 太行山 暴雨 时空分布 正交函数(EOF)分析 小波分析
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