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The σ-duals of Sequence Spaces
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作者 李龙锁 吴雅娟 赵玟亨 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期30-36,共7页
In this paper, the σ_duals of two classes important sequence spaces l 1(X) and l ∞(X) are investigated, and shows that some topology properties of locally convex space (X,τ) can be characterized by the σ _dua... In this paper, the σ_duals of two classes important sequence spaces l 1(X) and l ∞(X) are investigated, and shows that some topology properties of locally convex space (X,τ) can be characterized by the σ _duals. The criterions of bounded sets in l 1(X) and l ∞(X ) with respect to the weak topologies generated by the σ _duals are obtained. Furthermore, a Schur type result and an automatic continuity theorem of matrix transformation are established. 展开更多
关键词 sequence spaces σ_duals subseries convergence
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SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:5
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作者 Harun Polat Feyzi Basar 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期254-266,共13页
Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Alta... Kizmaz [13] studied the difference sequence spaces ∞(A), c(A), and co(A). Several article dealt with the sets of sequences of m-th order difference of which are bounded, convergent, or convergent to zero. Altay and Basar [5] and Altay, Basar, and Mursaleen [7] introduced the Euler sequence spaces e0^r, ec^r, and e∞^r, respectively. The main purpose of this article is to introduce the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m))consisting of all sequences whose mth order differences are in the Euler spaces e0^r, ec^r, and e∞^r, respectively. Moreover, the authors give some topological properties and inclusion relations, and determine the α-, β-, and γ-duals of the spaces e0^r△^(m)), ec^r△^(m)), and e∞^r△^(m)), and the Schauder basis of the spaces e0^r△^(m)), ec^r△^(m)). The last section of the article is devoted to the characterization of some matrix mappings on the sequence space ec^r△^(m)). 展开更多
关键词 Difference sequence spaces of order m Schauder basis the α- β- and γ-duals matrix mappings
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COLLECTIVELY COMPACT COMPOSITION OPERATOR SEQUENCES BETWEEN BERGMAN AND HARDY SPACES 被引量:3
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作者 王茂发 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2004年第2期206-212,共7页
This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions fo... This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions for composition operator sequences to be collectively compact between weighted Bergman spaces are given 展开更多
关键词 Bergman space Hardy space composition operator collectively compact operator sequence
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CHARACTERIZATIONS OF COMPACT OPERATORS ON SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:2
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作者 Ivana Djolovi Eberhard Malkowsky 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1465-1474,共10页
In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ (... In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ ( m ) ) and e r ∞ (△ ( m ) ) and characterized some classes of matrix transformations on them. In our paper, we add a new supplementary aspect to their research by characterizing classes of compact operators on those spaces. For that purpose, the spaces are treated as the matrix domains of a triangle in the classical sequence spaces c 0 , c and ∞ . The main tool for our characterizations is the Hausdorff measure of noncompactness. 展开更多
关键词 difference sequence spaces of order m matrix transformations compact operators Hausdorff measure of noncompactness
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ON SPECTRAL PROPERTIES OF A NEW OPERATOR OVER SEQUENCE SPACES c AND c_0 被引量:1
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作者 Ezgi ERDOGAN Vatan KARAKAYA 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1481-1494,共14页
In this work, we classify and calculate spectra such as point spectrum, continuous spectrum and residual spectrum over sequences spaces?∞, c and c0 according to a new matrix operator W which is obtained by matrix pr... In this work, we classify and calculate spectra such as point spectrum, continuous spectrum and residual spectrum over sequences spaces?∞, c and c0 according to a new matrix operator W which is obtained by matrix product. 展开更多
关键词 spectrum of an operator matrix transformation sequence space
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UNIVERSAL INTERPOLATING SEQUENCES ON SPACES OF ANALYTIC FUNCTIONS 被引量:1
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作者 B.Yousefi 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期68-72,共5页
This article derives the relation between universal interpolating sequences and some spectral properties of the multiplication operator by the independent variable z in case the underlying space is a Hilbert space of ... This article derives the relation between universal interpolating sequences and some spectral properties of the multiplication operator by the independent variable z in case the underlying space is a Hilbert space of functions analytic on the open unit disk. 展开更多
关键词 Hilbert spaces of analytic functions universal interpolating sequence multiplication operator invariant subspaces spectral properties
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MONOTONICITY IN ORLICZ-LORENTZ SEQUENCE SPACES EQUIPPED WITH THE ORLICZ NORM 被引量:1
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作者 巩万中 张道祥 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1577-1589,共13页
In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coeffi... In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coefficient in Aψ,w are discussed. 展开更多
关键词 Orlicz-Lorentz sequence space Orlicz norm point of upper (lower) local uni-form monotonicity uniform monotonicity monotone coefficient
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Multipliers into Sequence Spaces
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作者 岳修奎 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期20-26,共7页
This paper describes characteristics of (A p,α,l q) with 0【p≤1,α】0 and p≤q≤∞. As the corollaries, the characteristics of (A p,l q),(H p,l q),(G p,l q) and (B p,l q) with 0【p≤1 and p≤q≤∞ are ob... This paper describes characteristics of (A p,α,l q) with 0【p≤1,α】0 and p≤q≤∞. As the corollaries, the characteristics of (A p,l q),(H p,l q),(G p,l q) and (B p,l q) with 0【p≤1 and p≤q≤∞ are obtained. (H p,l q) and (H p,H q) with 1【p【∞ and 1≤q≤∞ are also studied. 展开更多
关键词 weighted Bergman space Hardy space sequence space MULTIPLIER Able dual
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THE SPACES OF CESRO ALMOST CONVERGENT SEQUENCES AND CORE THEOREMS
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作者 Kuddusi Kayaduman Mehmet Sengönül 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2265-2278,共14页
As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the ... As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the space of almost convergent sequences is so new (see [15]). The purpose of this paper is to introduce the new spaces ^ ~f and fo consisting of all sequences whose Ceshro transforms of order one are in the spaces f and ^ ~ f0, respectively. Also, in this paper, we show that ^ ~f and ^ ~f0 are linearly isomorphic to the spaces f and f0, respectively. The β- and γ-duals of the spaces ^ ~f and 2% are computed. Furthermore, the classes (^ ~f: μ) and (μ : f) of infinite matrices are characterized for any given sequence space μ, and determined the necessary and sufficient conditions on a matrix A to satisfy Bc-core(Ax) K-core(x), K-core(Ax) Bg-core(x), Bc-core(Ax) Be-core(x), Bc-core(Ax) t-core(x) for all x ∈ t∞. 展开更多
关键词 almost convergence matrix domain of a sequence space β- and γ-duals andmatrix transformations core theorems ISOMORPHISM
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ATOMIC DECOMPOSITION FOR B-VALUED R.V. SEQUENCE SPACES
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作者 李驭繁 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期151-159,共9页
In this article,atomic decompositions and the duals of some B-valued r.v.se- quence spaces are investigated.The results show that it closely depends on the geometrical properties of the sequence that take values in.
关键词 Atomic decomposition B-valued r.v.sequence space DUAL geometry of Banach space
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OFDM系统中一种双重混沌加密安全传输方案
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作者 侯艳丽 李子龙 《微电子学与计算机》 2025年第3期127-134,共8页
针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)通信系统中存在的信息安全传输问题,提出了一种双重混沌加密安全传输方案。第一重加密为利用混沌加密矩阵对信号星座图进行置乱,其中混沌加密矩阵由复合离散混沌序... 针对正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)通信系统中存在的信息安全传输问题,提出了一种双重混沌加密安全传输方案。第一重加密为利用混沌加密矩阵对信号星座图进行置乱,其中混沌加密矩阵由复合离散混沌序列作用到三层神经网络得到;第二重加密为利用复合离散混沌序列控制相位旋转因子对经过离散傅里叶逆变换后的信号进行相位旋转。仿真结果表明,采用所提出的双重加密方案进行传输,合作接收方的误码率低于不采用加密的OFDM系统和只采用第一重加密方案的OFDM系统,非合作方的误码率始终保持在0.5左右,密钥空间为2^(311),使系统具有较好的安全性能。 展开更多
关键词 正交频分复用 复合离散混沌序列 神经网络 相位旋转 密钥空间
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东营凹陷梁东地区古近系沙三中亚段层序地层划分及石油地质意义 被引量:1
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作者 曲星宇 《岩性油气藏》 北大核心 2025年第2期166-177,共12页
利用三维地震和测录井资料,对东营凹陷梁东地区古近系沙三中亚段的层序地层特征开展了研究,并对层序内部体系域组成、结构、沉积特征以及空间变化规律进行了分析。研究结果表明:①东营凹陷梁东地区古近系沙三中亚段内部可划分出高位体系... 利用三维地震和测录井资料,对东营凹陷梁东地区古近系沙三中亚段的层序地层特征开展了研究,并对层序内部体系域组成、结构、沉积特征以及空间变化规律进行了分析。研究结果表明:①东营凹陷梁东地区古近系沙三中亚段内部可划分出高位体系域(HST)、下降体系域(FSST)、低位体系域(LST)和湖侵体系域(TST),反映其经历了一次完整的基准面变化旋回。受沉积物供给和可容纳空间的侧向变化,供源主体位置沙三中亚段发育完整的层序序列。在沉积主体两侧,各体系域的地层厚度逐渐减薄,岸线迁移特征不明显。②研究区FSST沉积相以三角洲前缘为主体,可划分为水下分流河道、河口坝等微相,也可见少量重力流沉积微相,LST在演化序列上继承了FSST的沉积特征,以三角洲—重力流体系为主,但进一步向盆地方向推进。LST的沉积中心相较FSST西移,显示了LST中沉积体系的远距离推进特征。③研究区F1生长断裂的强烈活动控制了砂体分布,断层上、下盘产生的沉降差异使沉积物供给和可容纳空间均产生了变化,导致各体系域几何形态特征和地层叠置关系沿物源方向发生了变化,断层上盘高沉降、高可容纳空间区域的体系域发育完整,砂地比最大;断层下盘高地势、低沉降、低可容纳空间区域,HST和LST的厚度显著减小,砂地比也相对较小。④研究区HST由厚层暗色泥岩和油页岩构成,可作为良好的烃源岩;LST和FSST的三角洲和重力流砂体是主要储集层;TST形成了广泛的暗色泥岩可作为盖层。沙三中亚段各体系域在垂向上构成了良好的生储盖配置关系。 展开更多
关键词 层序地层学 四分体系域 水下分流河道 河口坝等微相 重力流 可容纳空间 沙河街组三段 古近系 梁东地区 东营凹陷
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CE-T_(1)_SPACE序列在肺癌脑转移瘤中的应用价值
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作者 杜勇 杨婷婷 +5 位作者 李建红 甄光 张光强 杨丹 黄依莲 王春红 《河南医学研究》 2025年第4期729-733,共5页
目的探讨可变翻转角快速自旋回波T_(1)对比增强序列(CE-T_(1)_SPACE)在肺癌脑转移瘤中的应用价值。方法选择自2022年1月至2024年9月于信阳市中心医院接受3.0 T MRI扫描的肺癌并脑转移瘤患者45例,患者分别接受磁共振平扫和T_(1)对比增强... 目的探讨可变翻转角快速自旋回波T_(1)对比增强序列(CE-T_(1)_SPACE)在肺癌脑转移瘤中的应用价值。方法选择自2022年1月至2024年9月于信阳市中心医院接受3.0 T MRI扫描的肺癌并脑转移瘤患者45例,患者分别接受磁共振平扫和T_(1)对比增强快速小翻转角梯度回波2 d序列(CE-T_(1)_fl2d)、T_(1)对比增强磁化准备超快速梯度回波序列(CE-T_(1)_MPRAGE)和T_(1)对比增强可变翻转角快速自旋回波序列(CE-T_(1)_SPACE)检查,由2名高年资医生对磁共振图像判读,测量转移灶长径大小,将所有病灶分为<3 mm、3~10 mm、>10 mm,记录病灶的部位;比较3种序列对不同长径、不同部位肺癌脑转移瘤检出率的差异。结果CE-T_(1)_fl2d、CE-T_(1)_MPRAGE和CE-T_(1)_SPACE序列对肺癌脑转移瘤病灶的检出率依次升高(分别为70.0%、89.7%、99.0%),差异有统计学意义(P<0.05)。CE-T_(1)_fl2d、CE-T_(1)_MPRAGE和CE-T_(1)_SPACE序列对长径<3 mm肺癌脑转移瘤检出率(分别为45.2%、78.6%、97.6%)依次升高,差异有统计学意义(P<0.05);CE-T_(1)_fl2d序列对于3~10 mm肺癌脑转移瘤检出率低于CE-T_(1)_MPRAGE和CE-T_(1)_SPACE序列(分别为87.0%、98.0%、100.0%),差异有统计学意义(P<0.05)。CE-T_(1)_fl2d、CE-T_(1)_MPRAGE和CE-T_(1)_SPACE序列脑凸面表浅区(分别为62.2%、91.1%、100.0%)、灰白质交界区(分别为79.7%、94.6%、100.0%)的检出率依次升高,差异有统计学意义(P<0.05);CE-T_(1)_fl2d、CE-T_(1)_MPRAGE序列对于小脑及脑干区转移灶检出率低于CE-T_(1)_SPACE序列(分别为46.4%、60.7%、92.9%),差异有统计学意义(P<0.05);CE-T_(1)_fl2d序列对于基底节区检查率低于CE-T_(1)_SPACE序列(分别为66.7%、95.8%),差异有统计学意义(P<0.05)。结论CE-T_(1)_SPACE序列对肺癌脑转移瘤病灶检出率优于CE-T_(1)_fl2d、CE-T_(1)_MPRAGE序列,尤其是<3 mm、脑凸面表浅区、灰白质交界区、小脑及脑干区转移灶,值得临床推广应用。 展开更多
关键词 肺癌 脑转移瘤 SPACE序列
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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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SOME GEOMETRIC PROPERTIES OF A NEW DIFFERENCE SEQUENCE SPACE INVOLVING LACUNARY SEQUENCES 被引量:1
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作者 Murat KARAKAS Mikail ET Vatan KARAKAYA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1711-1720,共10页
In this paper, we define a new generalized difference sequence space involving lacunary sequence. Then, we examine k-NUC property and property (β) for this space and also show that it is not rotund where p = (pr)... In this paper, we define a new generalized difference sequence space involving lacunary sequence. Then, we examine k-NUC property and property (β) for this space and also show that it is not rotund where p = (pr) is a bounded sequence of positive real numbers with pr ≥ 1 for all r ∈ N. 展开更多
关键词 difference sequence space lacunary sequence k-NUC property ROTUNDITY Luxemburg norm
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ON THE m^(th) ORDER DIFFERENCE SEQUENCE SPACE OF GENERALIZED WEIGHTED MEAN AND COMPACT OPERATORS 被引量:1
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作者 Metin BASARIR Emrah Evren KARA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期797-813,共17页
In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-di... In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-difference means are in the linear space l(p) defined by I.J.Maddox. Also, we determine the basis of this space and compute its α-, β- and γ-duals. Further, we give the characterization of the classes of matrix mappings from l(u, v, p, △(m)) to l∞, c, and co. Finally, we apply the Hausdorff measure of noncompacness to characterize some classes of compact operators given by matrices on the space lp(U, v, △(m)) (1 ≤ p 〈 ∞). 展开更多
关键词 Paranormed sequence spaces difference sequence spaces weighted mean α- β γ-duals matrix mappings Hausdorff measure of noncompactness compactoperators
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High-Sensitivity Acquisition of Ultrahigh Dynamic Direct Sequence Spread Spectrum Signals in Space Communications 被引量:2
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作者 徐颖 袁洪 《China Communications》 SCIE CSCD 2013年第10期26-36,共11页
According to the requirements of the high-sensitivity acquisition of Direct Sequence Spread Spectrum(DSSS) signals under ultrahigh dynamic environments in space communications, a three-dimensional joint search of the ... According to the requirements of the high-sensitivity acquisition of Direct Sequence Spread Spectrum(DSSS) signals under ultrahigh dynamic environments in space communications, a three-dimensional joint search of the phase of Pseudo-Noise-code(PN-code),Doppler frequency and its rate-of-change is presented to achieve high sensitivity in sensing high-frequency dynamics. By eliminating the correlation peak loss caused by ultrahigh Doppler frequency and its rate-of-change offset,the proposed method improves the acquisition sensitivity by increasing the non-coherent accumulation time. The validity of the algorithm is proved by theoretical analysis and simulation results. It is shown that signals with a carrier- to-noise ratio as low as 39 dBHz can be captured with high performance when the Doppler frequency is up to ±1 MHz and its rate-of-change is up to ±200 kHz/s. 展开更多
关键词 direct sequence spread spectrum signals space communications ACQUISITION high sensitivity ultrahigh dynamic
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REFLEXIVITY OF POWERS OF THE MULTIPLICATION OPERATOR ON SPECIAL FUNCTION SPACES 被引量:2
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作者 B. Yousefi Sh. Khoshdel 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2279-2284,共6页
In this paper we present sufficient conditions for reflexivity of any powers of the multiplication operator acting on Banach spaces of formal Laurent series.
关键词 reflexive operator Banaeh space of Laurent series associated with a sequenceβ bounded point evaluation
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BANACH SPACES AND INEQUALITIES ASSOCIATED WITH NEW GENERALIZATION OF CESàRO MATRIX 被引量:1
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作者 Feyzi BASAR Hadi ROOPAEI 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1518-1536,共19页
Let the triangle matrix A^(ru)be a generalization of the Cesàro matrix and U∈{c_(0),c,l_(∞)}.In this study,we essentially deal with the space U(A^(ru))defined by the domain of A^(ru)in the space U and give the ... Let the triangle matrix A^(ru)be a generalization of the Cesàro matrix and U∈{c_(0),c,l_(∞)}.In this study,we essentially deal with the space U(A^(ru))defined by the domain of A^(ru)in the space U and give the bases,and determine the Kothe-Toeplitz,generalized K?theToeplitz and bounded-duals of the space U(A^(ru)).We characterize the classes(l_(∞)(A^(ru)):l_(∞)),(l_(∞)(A^(ru)):c),(c(A^(ru)):c),and(U:V(A^(ru)))of infinite matrices,where V denotes any given sequence space.Additionally,we also present a Steinhaus type theorem.As an another result of this study,we investigate the l_(p)-norm of the matrix A^(ru)and as a result obtaining a generalized version of Hardy's inequality,and some inclusion relations.Moreover,we compute the norm of well-known operators on the matrix domain l_(p)(A^(ru)). 展开更多
关键词 matrix domain normed sequence space duals and matrix transformations
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ON ALMOST SURE CONVERGENCE OF WEIGHTED SUMS OF RANDOM ELEMENT SEQUENCES
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作者 甘师信 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1021-1028,共8页
We mainly study the almost sure limiting behavior of weighted sums of the form ∑ni=1 aiXi/bn , where {Xn, n ≥ 1} is an arbitrary Banach space valued random element sequence or Banach space valued martingale differen... We mainly study the almost sure limiting behavior of weighted sums of the form ∑ni=1 aiXi/bn , where {Xn, n ≥ 1} is an arbitrary Banach space valued random element sequence or Banach space valued martingale difference sequence and {an, n ≥ 1} and {bn,n ≥ 1} are two sequences of positive constants. Some new strong laws of large numbers for such weighted sums are proved under mild conditions. 展开更多
关键词 Strong law of large number almost sure convergence Lp convergence weighted sums Banach space valued random element sequence Banach space martingale difference sequence
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