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PRECISE ASYMPTOTICS IN SELF-NORMALIZED SUMS OF ITERATED LOGARITHM FOR MULTIDIMENSIONALLY INDEXED RANDOM VARIABLES 被引量:3
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作者 Jiang Chaowei Yang Xiaorong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第1期87-94,共8页
In the case of Z+^d(d ≥ 2)-the positive d-dimensional lattice points with partial ordering ≤, {Xk,k∈ Z+^d} i.i.d, random variables with mean 0, Sn =∑k≤nXk and Vn^2 = ∑j≤nXj^2, the precise asymptotics for ∑... In the case of Z+^d(d ≥ 2)-the positive d-dimensional lattice points with partial ordering ≤, {Xk,k∈ Z+^d} i.i.d, random variables with mean 0, Sn =∑k≤nXk and Vn^2 = ∑j≤nXj^2, the precise asymptotics for ∑n1/|n|(log|n|dP(|Sn/Vn|≥ε√log log|n|) and ∑n(logn|)b/|n|(log|n|)^d-1P(|Sn/Vn|≥ε√log n),as ε↓0,is established. 展开更多
关键词 multidimensionally indexed random variable precise asymptotics self-normalized sum Davislaw of large numbers law of iterated logarithm.
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A Note on “Limit Distributions of Self-Normalized Sums” Using Cauchy-Generated Samples
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作者 Jan Vrbik 《Applied Mathematics》 2019年第11期863-875,共13页
In this case study, we would like to illustrate the utility of characteristic functions, using an example of a sample statistic defined for samples from Cauchy distribution. The derivation of the corresponding asympto... In this case study, we would like to illustrate the utility of characteristic functions, using an example of a sample statistic defined for samples from Cauchy distribution. The derivation of the corresponding asymptotic probability density function is based on [1], elaborating and expanding the individual steps of their presentation, and including a small extension;our reason for such a plagiarism is to make the technique, its mathematical tools and ingenious arguments available to the widest possible audience. 展开更多
关键词 self-normalized sum CAUCHY Distribution Characteristic Functions FOURIER Transform Padé Approximation
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A strong approximation of self-normalized sums 被引量:1
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作者 CSRG Miklós HU ZhiShui 《Science China Mathematics》 SCIE 2013年第1期149-160,共12页
Let {X,Xn,n1} be a sequence of independent identically distributed random variables with EX=0 and assume that EX2I(|X|≤x) is slowly varying as x→∞,i.e.,X is in the domain of attraction of the normal law.In this pap... Let {X,Xn,n1} be a sequence of independent identically distributed random variables with EX=0 and assume that EX2I(|X|≤x) is slowly varying as x→∞,i.e.,X is in the domain of attraction of the normal law.In this paper a Strassen-type strong approximation is established for self-normalized sums of such random variables. 展开更多
关键词 strong approximation self-normalized sums domain of attraction of the normal law
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Berry-Esseen bounds for self-normalized sums of locally dependent random variables
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作者 Zhuo-Song Zhang 《Science China Mathematics》 SCIE CSCD 2024年第11期2629-2652,共24页
The Berry-Esseen bound provides an upper bound on the Kolmogorov distance between a random variable and the normal distribution.In this paper,we establish Berry-Esseen bounds with optimal rates for self-normalized sum... The Berry-Esseen bound provides an upper bound on the Kolmogorov distance between a random variable and the normal distribution.In this paper,we establish Berry-Esseen bounds with optimal rates for self-normalized sums of locally dependent random variables,assuming only a second-moment condition.Our proof leverages Stein's method and introduces a novel randomized concentration inequality,which may also be of independent interest for other applications.Our main results have applied to self-normalized sums of m-dependent random variables and graph dependency models. 展开更多
关键词 Berry-Esseen bounds self-normalized sums local dependence m-dependence graph dependency
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SELF-NORMALIZED CENTRAL LIMIT THEOREM AND ESTIMATION OF VARIANCE OF PARTIAL SUMS FOR NEGATIVE DEPENDENT RANDOM VARIABLES 被引量:1
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作者 Zhang Lixin\ Shi StrongwayDept.of Math.,Zhejiang Univ.,Xixi Campus,Hangzhou 310028,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期326-334,共9页
Let {X n,n≥1} be a stationary LNQD or NA sequence satisfying EX 1=μ,EX 2 1<∞ and (Var S n)/n→σ 2 as n→∞.In this paper a class of self-normalized central limit theorems and estimators of Var S n are ... Let {X n,n≥1} be a stationary LNQD or NA sequence satisfying EX 1=μ,EX 2 1<∞ and (Var S n)/n→σ 2 as n→∞.In this paper a class of self-normalized central limit theorems and estimators of Var S n are studied.The weak and strong consistency of the estimators of Var S n are presented. 展开更多
关键词 estimation negative dependence CONSISTENCY variance of partial sums.
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A weak invariance principle for self-normalized products of sums of mixing sequences
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作者 FU Ke-ang HUANG Wei 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期183-189,共7页
Let variables in the {X, Xn, n ≥ 1} be a sequence of strictly stationary φ-mixing positive random domain of attraction of the normal law. Under some suitable conditions the principle for self-normalized products of ... Let variables in the {X, Xn, n ≥ 1} be a sequence of strictly stationary φ-mixing positive random domain of attraction of the normal law. Under some suitable conditions the principle for self-normalized products of partial sums is obtained. 展开更多
关键词 self-normalized product domain of attraction of the normal law Φ-MIXING Wiener process.
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Ext-ICAS:A Novel Self-Normalized Extractive Intra Cosine Attention Similarity Summarization
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作者 P.Sharmila C.Deisy S.Parthasarathy 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期377-393,共17页
With the continuous growth of online news articles,there arises the necessity for an efficient abstractive summarization technique for the problem of information overloading.Abstractive summarization is highly complex... With the continuous growth of online news articles,there arises the necessity for an efficient abstractive summarization technique for the problem of information overloading.Abstractive summarization is highly complex and requires a deeper understanding and proper reasoning to come up with its own summary outline.Abstractive summarization task is framed as seq2seq modeling.Existing seq2seq methods perform better on short sequences;however,for long sequences,the performance degrades due to high computation and hence a two-phase self-normalized deep neural document summarization model consisting of improvised extractive cosine normalization and seq2seq abstractive phases has been proposed in this paper.The novelty is to parallelize the sequence computation training by incorporating feed-forward,the self-normalized neural network in the Extractive phase using Intra Cosine Attention Similarity(Ext-ICAS)with sentence dependency position.Also,it does not require any normalization technique explicitly.Our proposed abstractive Bidirectional Long Short Term Memory(Bi-LSTM)encoder sequence model performs better than the Bidirectional Gated Recurrent Unit(Bi-GRU)encoder with minimum training loss and with fast convergence.The proposed model was evaluated on the Cable News Network(CNN)/Daily Mail dataset and an average rouge score of 0.435 was achieved also computational training in the extractive phase was reduced by 59%with an average number of similarity computations. 展开更多
关键词 Abstractive summarization natural language processing sequence-tosequence learning(seq2seq) self-normALIZATION intra(self)attention
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2010—2023年北京市西城区猩红热流行病学特征及CUSUM模型的预警分析
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作者 秦迪 魏孝侃 +5 位作者 马春娜 管秀刚 陈瑜 孙景異 肖征 初艳慧 《预防医学情报杂志》 2025年第6期746-752,共7页
目的 分析2010—2023年北京市西城区猩红热的流行特征,并结合累积和(CUSUM)模型进行预警分析,为制定有针对性的防控措施提供科学依据。方法 应用描述性流行病学方法对2010—2023年北京市西城区猩红热病例进行分析,使用SPSS 25.0软件进... 目的 分析2010—2023年北京市西城区猩红热的流行特征,并结合累积和(CUSUM)模型进行预警分析,为制定有针对性的防控措施提供科学依据。方法 应用描述性流行病学方法对2010—2023年北京市西城区猩红热病例进行分析,使用SPSS 25.0软件进行数据整理分析,率的比较采用χ^(2)检验,R 4.3.3软件绘制发病率分布热图,应用CUSUM模型探测猩红热流行的起始时间,检验水准α=0.05。结果 2010—2023年,北京市西城区共报告猩红热病例3 328例,年均发病率为18.84/10万,不同年份发病率差异有统计学意义(χ^(2)=1 450.543,P<0.001;χ_(趋势)^(2)=238.637,P<0.001)。2011年报告病例数及发病率最高(504例,40.54/10万);2014年和2017—2018年分别出现2次反弹,发病率分别为30.62/10万、32.09/10万和33.03/10万;2020—2022年为低发年,年均发病率为1.85/10万,较2010—2019年下降了92.35%。猩红热发病具有显著的季节性,4至6月和11月至次年1月为发病高峰期,2020—2023年流行高峰并不明显,流行起始时间最早为每年的第11周和第39周,不同月份发病率差异有统计学意义(χ^(2)=1 260.787,P<0.001)。男性年均发病率高于女性(χ^(2)=228.578,P<0.001)。3~9岁发病人数最多,3岁~组和6岁~组发病率较高,不同年龄组发病率差异有统计学意义(χ^(2)=37 869.544,P<0.001)。病例以学生(70.43%)和幼托儿童(27.46%)为主。年均报告病例数和年均发病率最高的3个街道分别为展览路、新街口和德胜街道,月均发病率最高的为展览路街道5月发病率,各地区发病率差异有统计学意义(χ^(2)=315.562,P<0.001)。结论 2010—2023年北京市西城区猩红热发病率整体呈波动下降趋势,流行的起始时间在每年的3月和10月,3~9岁年龄组的小学生及幼托儿童为主要发病人群。流行前期应做好预测预警,加强对小学及托幼机构等重点场所和重点区域的监测与报告,严格落实各项防控措施,防止疫情出现反弹。 展开更多
关键词 猩红热 A组链球菌 流行病学特征 累积和模型
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A note on self-normalized Dickey-Fuller test for unit root in autoregressive time series with GARCH errors 被引量:1
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作者 YANG Xiao-rong ZHANG Li-xin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期197-201,共5页
In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test s... In this article, the unit root test for AR(p) model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test statistics is derived under the weak conditions. 展开更多
关键词 unit root AR (p)-GARCH (1 1) self-normalized Dickey-Fuller test statistic.
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基于CUSUM方法的胚胎冻融技术专科培训过程动态分析:存活率与操作时间的双维度评价
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作者 竺海燕 赵晨琼 《全科医学临床与教育》 2025年第11期1007-1009,1024,F0002,F0003,共6页
目的分析胚胎实验室技术员通过个体化胚胎冻融技术培训的累积和学习曲线(CUSUM),探讨专科技术员达到技术熟练程度的时间及随着时间推移保持胚胎冻融技术的熟练程度。方法选取2017年7月至2024年6月以来入职浙江大学医学院附属邵逸夫医院... 目的分析胚胎实验室技术员通过个体化胚胎冻融技术培训的累积和学习曲线(CUSUM),探讨专科技术员达到技术熟练程度的时间及随着时间推移保持胚胎冻融技术的熟练程度。方法选取2017年7月至2024年6月以来入职浙江大学医学院附属邵逸夫医院生殖中心的胚胎实验室初级专科技术学员共10名,采用CUSUM分析方法,对10名专科技术学员在25 d训练周期内的胚胎冷冻复苏存活率与操作时间两项关键指标进行动态监测。结果学员操作时间CUSUM图分为三个显著阶段:初始下降阶段(1~8 d)、加速下降阶段(9~17 d)及稳定下降阶段(18~25 d)。存活率CUSUM曲线形态分析显示三个关键阶段:快速下降期(1~10 d)、减缓下降期(11~17 d)及稳定期(18~25 d)。进入稳定维持阶段,各学员胚胎冷冻复苏存活率CUSUM曲线终值分布在-160~-215之间,差异相对操作时间CUSUM曲线较小。结论CUSUM方法对胚胎冷冻操作时间及胚胎冷冻复苏存活率进行双维度动态分析,为优化胚胎技术员培训设计、提升教学效能提供了实证依据。 展开更多
关键词 累积和学习曲线 辅助生殖技术 专科技术员 胚胎冻融技术
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Self-Normalized Exponential Inequalities for Martingales
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作者 Shen WANG 《Journal of Mathematical Research with Applications》 CSCD 2019年第3期304-314,共11页
We give an extension of Delyon's inequality for locally square integrable martingales.The result is very useful for establishing self-normalized exponential inequality for martingales.An application to linear regr... We give an extension of Delyon's inequality for locally square integrable martingales.The result is very useful for establishing self-normalized exponential inequality for martingales.An application to linear regressions is discussed. 展开更多
关键词 EXPONENTIAL INEQUALITIES self-normalized PROCESSES MARTINGALES
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A Verification Theorem for Feedback Nash Equilibrium in Multiple-Player Nonzero-Sum Impulse Game 被引量:1
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作者 Ruihai Li Yaoyao Tan +1 位作者 Xiaojie Su Jiangshuai Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期648-650,共3页
Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate... Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate this impulse game problem with the modified objective function including interaction costs among the players in a discontinuous fashion,and subsequently,to derive a verification theorem for identifying the feedback Nash equilibrium strategy. 展开更多
关键词 impulse game feedback Nash equilibrium multiple player feedback nash equilibrium strategy impulse game problem nonzero sum modified objective function impulse controlsour
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On the Triple Sums of Hecke Eigenvalues on Certain Polynomials
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作者 HUA Guodong 《数学进展》 北大核心 2025年第6期1261-1277,共17页
Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized... Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized Fourier coefficients,respectively.In this paper,we investigate the correlations of triple sums associated to these Fourier coefficientsλ_(f)(n),λ_(g)(n),λ_(h)(n)over certain polynomials,and obtain some power-saving asymptotic estimates which beat the trivial bounds. 展开更多
关键词 Hecke eigenvalue triple correlation sum automorphic L-function asymptotic behavior
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基于Summing Mixer的小型录音棚录音系统设计与实现——某研究院声像中心录音棚建设实例
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作者 刘牧 苑方磊 +1 位作者 宋华华 李杰 《电声技术》 2025年第1期20-25,共6页
小型录音棚通常具有空间小、投资省、设备系统简约以及使用灵活高效等特点。通过设计一个小型录音棚录音系统,提出以Summing Mixer为路由与控制核心的系统整体设计方案,包括拾音系统、数字音频系统、监听系统以及硬件效果器系统等分系... 小型录音棚通常具有空间小、投资省、设备系统简约以及使用灵活高效等特点。通过设计一个小型录音棚录音系统,提出以Summing Mixer为路由与控制核心的系统整体设计方案,包括拾音系统、数字音频系统、监听系统以及硬件效果器系统等分系统设计。通过配备硬件压缩器、限制器、均衡器以及混响器等设备,为小型数字录音系统添加了“模拟味”。最后,探讨了设计系统在录音实践中实现零延迟返送监听、外部设备多链路接入、母带制作路由等技术优势。 展开更多
关键词 录音 小型录音棚 summing Mixer 系统设计
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三类基于Weil sums的线性码
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作者 廖崟琎 何佳维 《南昌航空大学学报(自然科学版)》 2025年第2期35-42,共8页
近年来,少重量线性码被广泛地研究。少重量线性码在强正则图、密钥分享方案、关联方案以及认证码等领域均有应用。本文选取特定定义集,进而构造出有限域上的三类6-重量线性码,并借助Weil sums确定这三类线性码的重量分布情况。
关键词 线性码 重量分布 Weil sums
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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基于k-sums算法的四旋翼无人机飞行轨迹快速规划方法
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作者 杨智玲 程玮 《长春师范大学学报》 2025年第6期68-74,共7页
四旋翼无人机在进行轨迹规划时易受无人机运动学因素的影响,导致生成的飞行轨迹长度较长,规划效果较差。本研究提出基于k-sums算法的四旋翼无人机飞行轨迹快速规划方法。依据四旋翼无人机飞行轨迹规划原理,利用栅格划分法,将飞行空间环... 四旋翼无人机在进行轨迹规划时易受无人机运动学因素的影响,导致生成的飞行轨迹长度较长,规划效果较差。本研究提出基于k-sums算法的四旋翼无人机飞行轨迹快速规划方法。依据四旋翼无人机飞行轨迹规划原理,利用栅格划分法,将飞行空间环境进行初始化处理,求取无人机受到的引力场函数,并利用栅格间距离对飞行空间环境进行建模。结合无人机起始点计算无人机在不同飞行时刻的航向角,并将无人机的运动学因素作为变量,采用k-sums算法进行聚类,以此生成航迹点。基于此,对生成的飞行航迹点进行等时间间隔采样,得到飞行轨迹控制点,结合轨迹平滑度和碰撞安全性的代价函数,得到优化后的无人机飞行轨迹,实现四旋翼无人机飞行轨迹规划。实验结果表明,所提方法可以有效缩短无人机飞行路径长度,提高无人机的作业效率。 展开更多
关键词 k-sums算法 四旋翼无人机 飞行空间环境 航迹点 轨迹规划
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Geophysical data denoising using dictionary learning method with Ramanujan sums for oil and minerals exploration
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作者 Lakshmi Kuruguntla Mamatha Bandaru +3 位作者 Dokku Tejaswi Anup Kumar Mandpura Sravan Kumar Sikhakoli Vineela Chandra Dodda 《Artificial Intelligence in Geosciences》 2025年第2期374-383,共10页
Denoising is an important preprocessing step in seismic exploration that improves the signal-to-noise ratio(SNR)and helps identify oil and minerals.Dictionary learning(DL)is a promising method for noise attenuation.Th... Denoising is an important preprocessing step in seismic exploration that improves the signal-to-noise ratio(SNR)and helps identify oil and minerals.Dictionary learning(DL)is a promising method for noise attenuation.The DL extracts sparse features from noisy seismic data using over-complete dictionaries and performs denoising based on a threshold.However,the choice of threshold in DL greatly impacts the denoising results and the improvement in output SNR.Ramanujan’s sum(s)(RS)is a signal processing tool that exhibits derivative behavior and finds applications in edge detection and noise estimation of signals.Hence,we propose a novel DL method with threshold estimation based on RS to improve the output SNR.In this work,we estimate the noise variance of seismic data based on RS and use it as a threshold value for the DL method to perform denoising.We analyze the results of the proposed work on synthetically generated and field data sets.We perform simulations on noisy seismic data across a wide range of SNR values and tabulate the denoised results using the performance metrics SNR and mean squared error.The results indicate that the proposed method provides superior SNR and reduced mean squared error compared to MAD,SURE-based,and adaptive soft-thresholding techniques. 展开更多
关键词 Seismic denoising Ramanujan sum Dictionary learning 2D seismic data
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