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MAXIMAL FUNCTION CHARACTERIZATIONS OF HARDY SPACES ASSOCIATED WITH BOTH NON-NEGATIVE SELF-ADJOINT OPERATORS SATISFYING GAUSSIAN ESTIMATES AND BALL QUASI-BANACH FUNCTION SPACES
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作者 林孝盛 杨大春 +1 位作者 杨四辈 袁文 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期484-514,共31页
Assume that L is a non-negative self-adjoint operator on L^(2)(ℝ^(n))with its heat kernels satisfying the so-called Gaussian upper bound estimate and that X is a ball quasi-Banach function space onℝ^(n) satisfying som... Assume that L is a non-negative self-adjoint operator on L^(2)(ℝ^(n))with its heat kernels satisfying the so-called Gaussian upper bound estimate and that X is a ball quasi-Banach function space onℝ^(n) satisfying some mild assumptions.Let HX,L(ℝ^(n))be the Hardy space associated with both X and L,which is defined by the Lusin area function related to the semigroup generated by L.In this article,the authors establish various maximal function characterizations of the Hardy space HX,L(ℝ^(n))and then apply these characterizations to obtain the solvability of the related Cauchy problem.These results have a wide range of generality and,in particular,the specific spaces X to which these results can be applied include the weighted space,the variable space,the mixed-norm space,the Orlicz space,the Orlicz-slice space,and the Morrey space.Moreover,the obtained maximal function characterizations of the mixed-norm Hardy space,the Orlicz-slice Hardy space,and the Morrey-Hardy space associated with L are completely new. 展开更多
关键词 Hardy space ball quasi-Banach function space Gaussian upper bound estimate non-negative self-adjoint operator maximal function
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NEW DOOB'S MAXIMAL INEQUALITIES FOR MARTINGALES
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作者 郝志伟 李丽波 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期531-538,共8页
Let 1≤q≤∞,b be a slowly varying function and letΦ:[0,∞)■[0,∞)be an increasing convex function withΦ(0)=0 and■Φ(r)=∞.In this paper,we present a new class of Doob’s maximal inequality on Orlicz-Lorentz-Karam... Let 1≤q≤∞,b be a slowly varying function and letΦ:[0,∞)■[0,∞)be an increasing convex function withΦ(0)=0 and■Φ(r)=∞.In this paper,we present a new class of Doob’s maximal inequality on Orlicz-Lorentz-Karamata spaces LΦ,q,b.The results are new,even for the Lorentz-Karamata spaces withΦ(t)=tp,the Orlicz-Lorentz spaces with b≡1,and weak Orlicz-Karamata spaces with q=∞in the framework of LΦ,q,b-Moreover,we obtain some even stronger qualitative results that can remove the△2-condition of Liu,Hou and Wang(Sci China Math,2010,53(4):905-916). 展开更多
关键词 martingaleS Doob's inequality Orlicz-Lorentz-Karamata spaces convex functions
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Prognostic model for prostate cancer based on glycolysis-related genes and non-negative matrix factorization analysis
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作者 ZECHAO LU FUCAI TANG +6 位作者 HAOBIN ZHOU ZEGUANG LU WANYAN CAI JIAHAO ZHANG ZHICHENG TANG YONGCHANG LAI ZHAOHUI HE 《BIOCELL》 SCIE 2023年第2期339-350,共12页
Background:Establishing an appropriate prognostic model for PCa is essential for its effective treatment.Glycolysis is a vital energy-harvesting mechanism for tumors.Developing a prognostic model for PCa based on glyc... Background:Establishing an appropriate prognostic model for PCa is essential for its effective treatment.Glycolysis is a vital energy-harvesting mechanism for tumors.Developing a prognostic model for PCa based on glycolysis-related genes is novel and has great potential.Methods:First,gene expression and clinical data of PCa patients were downloaded from The Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO),and glycolysis-related genes were obtained from the Molecular Signatures Database(MSigDB).Gene enrichment analysis was performed to verify that glycolysis functions were enriched in the genes we obtained,which were used in nonnegative matrix factorization(NMF)to identify clusters.The correlation between clusters and clinical features was discussed,and the differentially expressed genes(DEGs)between the two clusters were investigated.Based on the DEGs,we investigated the biological differences between clusters,including immune cell infiltration,mutation,tumor immune dysfunction and exclusion,immune function,and checkpoint genes.To establish the prognostic model,the genes were filtered based on univariable Cox regression,LASSO,and multivariable Cox regression.Kaplan–Meier analysis and receiver operating characteristic analysis validated the prognostic value of the model.A nomogram of the risk score calculated by the prognostic model and clinical characteristics was constructed to quantitatively estimate the survival probability for PCa patients in the clinical setting.Result:The genes obtained from MSigDB were enriched in glycolysis functions.Two clusters were identified by NMF analysis based on 272 glycolysis-related genes,and a prognostic model based on DEGs between the two clusters was finally established.The prognostic model consisted of LAMPS,SPRN,ATOH1,TANC1,ETV1,TDRD1,KLK14,MESP2,POSTN,CRIP2,NAT1,AKR7A3,PODXL,CARTPT,and PCDHGB2.All sample,training,and test cohorts from The Cancer Genome Atlas(TCGA)and the external validation cohort from GEO showed significant differences between the high-risk and low-risk groups.The area under the ROC curve showed great performance of this prognostic model.Conclusion:A prognostic model based on glycolysis-related genes was established,with great performance and potential significance to the clinical application. 展开更多
关键词 GLYCOLYSIS Prostate cancer Tumor immune non-negative matrix factorization Prognostic model
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Non-Negative Adaptive Mechanism-Based Sliding Mode Control for Parallel Manipulators with Uncertainties
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作者 Van-Truong Nguyen 《Computers, Materials & Continua》 SCIE EI 2023年第2期2771-2787,共17页
In this paper,a non-negative adaptive mechanism based on an adaptive nonsingular fast terminal sliding mode control strategy is proposed to have finite time and high-speed trajectory tracking for parallel manipulators... In this paper,a non-negative adaptive mechanism based on an adaptive nonsingular fast terminal sliding mode control strategy is proposed to have finite time and high-speed trajectory tracking for parallel manipulators with the existence of unknown bounded complex uncertainties and external disturbances.The proposed approach is a hybrid scheme of the online non-negative adaptive mechanism,tracking differentiator,and nonsingular fast terminal sliding mode control(NFTSMC).Based on the online non-negative adaptive mechanism,the proposed control can remove the assumption that the uncertainties and disturbances must be bounded for the NFTSMC controllers.The proposed controller has several advantages such as simple structure,easy implementation,rapid response,chattering-free,high precision,robustness,singularity avoidance,and finite-time convergence.Since all control parameters are online updated via tracking differentiator and non-negative adaptive law,the tracking control performance at high-speed motions can be better in real-time requirement and disturbance rejection ability.Finally,simulation results validate the effectiveness of the proposed method. 展开更多
关键词 Parallel manipulator uncertainties and disturbances nonsingular fast terminal sliding mode control non-negative adaptive mechanism tracking differentiator
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Evaluating Partitioning Based Clustering Methods for Extended Non-negative Matrix Factorization (NMF)
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作者 Neetika Bhandari Payal Pahwa 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2043-2055,共13页
Data is humongous today because of the extensive use of World WideWeb, Social Media and Intelligent Systems. This data can be very important anduseful if it is harnessed carefully and correctly. Useful information can... Data is humongous today because of the extensive use of World WideWeb, Social Media and Intelligent Systems. This data can be very important anduseful if it is harnessed carefully and correctly. Useful information can beextracted from this massive data using the Data Mining process. The informationextracted can be used to make vital decisions in various industries. Clustering is avery popular Data Mining method which divides the data points into differentgroups such that all similar data points form a part of the same group. Clusteringmethods are of various types. Many parameters and indexes exist for the evaluationand comparison of these methods. In this paper, we have compared partitioningbased methods K-Means, Fuzzy C-Means (FCM), Partitioning AroundMedoids (PAM) and Clustering Large Application (CLARA) on secure perturbeddata. Comparison and identification has been done for the method which performsbetter for analyzing the data perturbed using Extended NMF on the basis of thevalues of various indexes like Dunn Index, Silhouette Index, Xie-Beni Indexand Davies-Bouldin Index. 展开更多
关键词 Clustering CLARA Davies-Bouldin index Dunn index FCM intelligent systems K-means non-negative matrix factorization(NMF) PAM privacy preserving data mining Silhouette index Xie-Beni index
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数理模型下抵押贷款共同保险的Martingale评价
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作者 李晨 李小春 《铜仁学院学报》 2011年第4期57-59,共3页
假设未偿付额可由风险信用评估得到,房产价格服从一般Ito过程,构建了抵押贷款共同保险的数理评价模型,利用Martingale评价方法,得到了房屋抵押贷款共同保险的精确定价公式。
关键词 抵押贷款 保险 martingale评价
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Martingale在控制论中的应用
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作者 袁震东 《信息与控制》 CSCD 北大核心 1989年第4期33-36,共4页
本文用工程界熟悉的语言阐述鞅(Martingale)的含义以及鞅论(包括随机积分和随机微分方程——随机分析)在系统辨识、自适应控制、随机控制与滤波中的应用.从而说明,鞅论是现代控制理论中一个重要工具,应该引起工程界的足够的重视.
关键词 系统辨识 自适应控制 控制论
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住房抵押贷款限额保险的Martingale评价
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作者 陈丽萍 《科技和产业》 2010年第12期107-108,133,共3页
引入期权定价理论,利用鞅定价方法,得到了房屋抵押贷款限额保险的精确定价公式,其中未偿付额为常数,房产价格服从一般ITO过程。
关键词 房屋抵押贷款 保险 期权 鞅定价
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随机利率下住房抵押贷款保险的创新及Martingale评价
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作者 陈丽萍 《湖南理工学院学报(自然科学版)》 CAS 2011年第4期19-21,共3页
在住房抵押贷款部分担保保证险的基础上进行了创新设计,并引入期权定价理论,利用鞅定价方法,分析了随机利率模型下该抵押贷款保险的定价问题,得到了该抵押贷款保险的无套利定价公式,其中房价服从一般扩散过程.Vasic?e kIto?
关键词 随机利率 抵押贷款 保险 期权 鞅定价
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跳扩散模型下住房抵押贷款限额保险的Martingale评价
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作者 李晨 陈丽萍 《安庆师范学院学报(自然科学版)》 2011年第4期38-40,66,共4页
利用特殊的鞅定价方法,得到了住房抵押贷款限额保险的定价公式,其中假设房价服从Merton跳扩散过程。
关键词 抵押贷款 保险 跳扩散 鞅定价
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LORENTZ MARTINGALE SPACES AND INTERPOLATION 被引量:7
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作者 范利萍 焦勇 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1143-1153,共11页
In this article, the authors introduce some new Lorentz spaces for martingales, which are extensions of Hardy spaces of martingales. Then they discuss their basic properties, embedding relationships, and interpolation... In this article, the authors introduce some new Lorentz spaces for martingales, which are extensions of Hardy spaces of martingales. Then they discuss their basic properties, embedding relationships, and interpolation spaces between them, during which the use of rearrangement good-λ-inequality plays an important role. 展开更多
关键词 martingale Lorentz space WEIGHT INTERPOLATION
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ATOMIC DECOATOMIC DECOMPOSITIONS AND DUALS OF WEAK HARDY SPACES OF B-VALUED MARTINGALES 被引量:6
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作者 马涛 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1439-1452,共14页
In this article, several weak Hardy spaces of Banach-space-valued martingales are introduced, some atomic decomposition theorems for them are established and their duals are investigated. The results closely depend on... In this article, several weak Hardy spaces of Banach-space-valued martingales are introduced, some atomic decomposition theorems for them are established and their duals are investigated. The results closely depend on the geometrical properties of the Banach space in which the martingales take values. 展开更多
关键词 martingale atomic decomposition weak Hardy space geometry of Banach space
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TWO-WEIGHT WEAK-TYPE MAXIMAL INEQUALITIES FOR MARTINGALES 被引量:4
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作者 任颜波 侯友良 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期402-408,共7页
In this article, some necessary and sufficient conditions are shown in order that the inequality of the form Ф1(λ)Pu(f^*〉λ)≤Ev (Ф2(C|f∞|)) holds with some constant C 〉 0 independent of martingale f... In this article, some necessary and sufficient conditions are shown in order that the inequality of the form Ф1(λ)Pu(f^*〉λ)≤Ev (Ф2(C|f∞|)) holds with some constant C 〉 0 independent of martingale f = (fn)n≥0 and λ 〉 0, where Фl and Ф2 are a pair of Young functions, f^*=sup n≥0|fn| adn f∞=lim n→∞ fn a.e. 展开更多
关键词 martingale WEIGHT weak-type inequality Young function
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GENERALIZED ROSENTHAL'S INEQUALITY FOR BANACH-SPACE-VALUED MARTINGALES 被引量:5
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作者 于林 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期305-312,共8页
A generalized Rosenthal's inequality for Banach-space-valued martingales is proved, which extends the corresponding results in the previous literatures and characterizes the p-uniform smoothness and q-uniform convexi... A generalized Rosenthal's inequality for Banach-space-valued martingales is proved, which extends the corresponding results in the previous literatures and characterizes the p-uniform smoothness and q-uniform convexity of the underlying Banach space. As an application of this inequality, the strong law of large numbers for Banach-space-valued martingales is also given. 展开更多
关键词 Rosenthal's inequality Ф-inequality martingaleS p-uniform smoothness q-uniform convexity
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Two-Parameter Banach Space Valued Strong Martingales and Characterizations of p-Smoothable Spaces 被引量:5
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作者 Gan Shi-xin Ye Chen Zhang Feng 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第4期387-392,共6页
In this paper we introduce the concept of two-parameterB-valued strong martingales and investigate some features of these strong martingales. We also characterizep-smoothable Banach spaces in terms of these strong mar... In this paper we introduce the concept of two-parameterB-valued strong martingales and investigate some features of these strong martingales. We also characterizep-smoothable Banach spaces in terms of these strong martingales. 展开更多
关键词 two-parameterB-valued strong martingale atomic decomposition p-smoothable
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INTERPOLATION OF LORENTZ-ORLICZ MARTINGALE SPACES 被引量:3
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作者 张传洲 潘誉 张学英 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1467-1474,共8页
In this paper, we apply function parameters to real interpolation of Lorentz- Orlicz martingale spaces. Some new interpolation theorems are formulated which generalize some known results in Lorentz spaces An introduce... In this paper, we apply function parameters to real interpolation of Lorentz- Orlicz martingale spaces. Some new interpolation theorems are formulated which generalize some known results in Lorentz spaces An introduced by Sharpley. 展开更多
关键词 martingale Lorentz-Orlicz space INTERPOLATION function parameter
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CONVERGENCE OF WEIGHTED AVERAGES OF MARTINGALES IN NONCOMMUTATIVE BANACH FUNCTION SPACES 被引量:4
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作者 张超 侯友良 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期735-744,共10页
Let x (xn)≥1 be a martingale on a noncommutative probability space n (M, r) and (wn)n≥1 a sequence of positive numbers such that Wn = ∑ k=1^n wk →∞ as n →∞ We prove that x = (x.)n≥1 converges in E(M... Let x (xn)≥1 be a martingale on a noncommutative probability space n (M, r) and (wn)n≥1 a sequence of positive numbers such that Wn = ∑ k=1^n wk →∞ as n →∞ We prove that x = (x.)n≥1 converges in E(M) if and only if (σn(x)n≥1 converges in E(.hd), where E(A//) is a noncommutative rearrangement invariant Banach function space with the Fatou property and σn(x) is given by σn(x) = 1/Wn ∑k=1^n wkxk, n=1, 2, .If in addition, E(Ad) has absolutely continuous norm, then, (an(x))≥1 converges in E(.M) if and only if x = (Xn)n≥1 is uniformly integrable and its limit in measure topology x∞∈ E(M). 展开更多
关键词 Weighted average noncommutative martingales noncommutative BanachfunCtion spaces uniform integrability
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Feature Extraction and Recognition for Rolling Element Bearing Fault Utilizing Short-Time Fourier Transform and Non-negative Matrix Factorization 被引量:24
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作者 GAO Huizhong LIANG Lin +1 位作者 CHEN Xiaoguang XU Guanghua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期96-105,共10页
Due to the non-stationary characteristics of vibration signals acquired from rolling element bearing fault, thc time-frequency analysis is often applied to describe the local information of these unstable signals smar... Due to the non-stationary characteristics of vibration signals acquired from rolling element bearing fault, thc time-frequency analysis is often applied to describe the local information of these unstable signals smartly. However, it is difficult to classitythe high dimensional feature matrix directly because of too large dimensions for many classifiers. This paper combines the concepts of time-frequency distribution(TFD) with non-negative matrix factorization(NMF), and proposes a novel TFD matrix factorization method to enhance representation and identification of bearing fault. Throughout this method, the TFD of a vibration signal is firstly accomplished to describe the localized faults with short-time Fourier transform(STFT). Then, the supervised NMF mapping is adopted to extract the fault features from TFD. Meanwhile, the fault samples can be clustered and recognized automatically by using the clustering property of NMF. The proposed method takes advantages of the NMF in the parts-based representation and the adaptive clustering. The localized fault features of interest can be extracted as well. To evaluate the performance of the proposed method, the 9 kinds of the bearing fault on a test bench is performed. The proposed method can effectively identify the fault severity and different fault types. Moreover, in comparison with the artificial neural network(ANN), NMF yields 99.3% mean accuracy which is much superior to ANN. This research presents a simple and practical resolution for the fault diagnosis problem of rolling element bearing in high dimensional feature space. 展开更多
关键词 time-frequency distribution non-negative matrix factorization rolling element bearing feature extraction
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THE MINIMAL OPERATOR AND WEIGHTED INEQUALITIES FOR MARTINGALES 被引量:3
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作者 左红亮 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期31-40,共10页
In this article the authors introduce the minimal operator on martingale spaces, discuss some one-weight and two-weight inequalities for the minimal operator and characterize the conditions which make the inequalities... In this article the authors introduce the minimal operator on martingale spaces, discuss some one-weight and two-weight inequalities for the minimal operator and characterize the conditions which make the inequalities hold. 展开更多
关键词 Minimal operator WEIGHT martingale inequality
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Atomic Decompositions of Weak Hardy Spaces of B-Valued Martingales 被引量:4
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作者 MA Tao LIU Peide 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期456-460,共5页
The atomic decompositions of weak Hardy spaces of Banach-space-valued martingales are given. With the help of the atomic decompositions, some inequalities for B-valued martingales are established in the case 0〈r≤1. ... The atomic decompositions of weak Hardy spaces of Banach-space-valued martingales are given. With the help of the atomic decompositions, some inequalities for B-valued martingales are established in the case 0〈r≤1. Here the results are connected closely with the p-uniform smoothness and q-uniform convexity of Banach spaces which the martingales take values in. 展开更多
关键词 atomic decomposition weak Hardy space B-valued martingale
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