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Almost perfect sequences based on cyclic difference sets 被引量:6
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作者 Chen Gang Zhao Zhengyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期155-159,共5页
The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interferenc... The perfect sequences are so ideal that all out-of-phase autocorrelation coefficients are zero, and if the sequences are used as the coding modulating signal for the phase-modulated radar, there will be no interference of side lobes theoretically. However, it has been proved that there are no binary perfect sequences of period 4 〈 n ≤ 12100. Hence, the almost perfect sequences with all out-of-phase autocorrelation coefficients as zero except one are of great practice in engineering. Currently, the cyclic difference set is one of most effective tools to analyze the binary sequences with perfect periodic autocorrelation function. In this article, two characteristic formulas corresponding to the autocorrelation and symmetric structure of almost perfect sequences are calculated respectively. All almost perfect sequences with period n, which is a multiple of 4, can be figured out by the two formulas. Several almost perfect sequences with different periods have been hunted by the program based on the two formulas and then applied to the simulation program and practical application for ionospheric sounding. 展开更多
关键词 Perfect sequence Almost perfect sequence Cyclic difference sets Autocorrelation coefficients Side lobes Ionospheric sounding
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ON SOME GENERALIZED DIFFERENCE PARANORMED SEQUENCE SPACES ASSOCIATED WITH MULTIPLIER SEQUENCE DEFINED BY MODULUS FUNCTION 被引量:5
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作者 Binod Chandra Tripathy Prabhat Chandra 《Analysis in Theory and Applications》 2011年第1期21-27,共7页
In this article we introduce the paranormed sequence spaces (f,A, Am,p), c0(f,A,Am,p) and L00(f,A, Am,p), associated with the multiplier sequence ∧ = (hk), defined by a modulus function f. We study their diff... In this article we introduce the paranormed sequence spaces (f,A, Am,p), c0(f,A,Am,p) and L00(f,A, Am,p), associated with the multiplier sequence ∧ = (hk), defined by a modulus function f. We study their different properties like solidness, symmetricity, completeness etc. and prove some inclusion results. 展开更多
关键词 paranorm solid space symmetric space difference sequence modulus function multiplier seuence
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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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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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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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SOME CLASSES OF DIFFERENCE SEQUENCES OF FUZZY NUMBERS DEFINED BY A SEQUENCE OF MODULI
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作者 Ayhan Esi Mehmet Aikgz 《Acta Mathematica Scientia》 SCIE CSCD 2011年第1期229-236,共8页
In this article, we introduce and examine some properties of new difference sequence spaces of fuzzy numbers defined using a sequence of modulus functions.
关键词 Fuzzy numbers paranorm difference sequences modulus function
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Some new generalized difference sequence spaces defined by a sequence of moduli
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作者 Vakeel A Khan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期104-108,共5页
The idea of difference sequence sets X(△) = {x = (xk) : △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence sp... The idea of difference sequence sets X(△) = {x = (xk) : △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence spaces and give some inclusion relations. 展开更多
关键词 difference sequence space sequence of moduli inclusion relation.
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NOTES ON THE SPECTRAL PROPERTIES OF THE WEIGHTED MEAN DIFFERENCE OPERATOR G(u,v;?) OVER THE SEQUENCE SPACE ?_1
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作者 Vatan KARAKAYA Ezgi ERDOGAN 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期477-486,共10页
In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1.... In the study by Baliarsingh and Dutta [Internat. J.Anal., Vol.2014(2014), Article ID 786437], the authors computed the spectrum and the fine spectrum of the product operator G (u, v; A) over the sequence space e1. The product operator G (u, v; △) over l1 is defined by (G(u,v;△)x)k=^k∑i=0ukvi(xi- xi-1) with xk = 0 for all k 〈 0, where x = (xk)∈e1,and u and v axe either constant or strictly decreasing sequences of positive real numbers satisfying certain conditions. In this article we give some improvements of the computation of the spectrum of the operator G (u, v; △) on the sequence space gl. 展开更多
关键词 Spectrum of an operator weighted mean difference operator sequence space
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On the Limiting Behavior of Weighted Partial Sums for B Valued Martingale Difference Sequences
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作者 Gan Shi-xin 1, Qiu De-hua 2 1.School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei, China 2. Department of Mathematics, Hengyang Teacher’s College, Hengyang 421008, Hunan, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第2期133-136,共4页
Let {Xn, n≥1} be a martingale difference sequence and {a nk , 1?k?n,n?1} an array of constant real numbers. The limiting behavior of weighted partial sums ∑ k=1 n a nk X k is investigated and some new results are ob... Let {Xn, n≥1} be a martingale difference sequence and {a nk , 1?k?n,n?1} an array of constant real numbers. The limiting behavior of weighted partial sums ∑ k=1 n a nk X k is investigated and some new results are obtained. 展开更多
关键词 p-smoothable Banach space weighted partial sum martingale difference sequence strong law of large numbers
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On some difference sequence spaces defined by a sequence of Orlicz functions
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作者 ASMA BEKTA■ i■dem 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2093-2096,共4页
The idea of difference sequence spaces was introduced in (K?zmaz, 1981) and this concept was generalized in (Et and olak, 1995). In this paper we define some difference sequence spaces by a sequence of Orlicz functi... The idea of difference sequence spaces was introduced in (K?zmaz, 1981) and this concept was generalized in (Et and olak, 1995). In this paper we define some difference sequence spaces by a sequence of Orlicz functions and establish some inclusion relations. 展开更多
关键词 微分序列 ORLICZ函数 收敛性 包含关系
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Analysis on Double-difference Earthquake Location and the Seismicity Pattern of the Yangjiang Earthquake Sequences
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作者 Kang Ying Yang Xuan Huang Wenhui Chen Xing Chen Guimei Lin Wei Wu Huadeng 《Earthquake Research in China》 2008年第1期73-81,共9页
The locations of about 400 earthquakes in Yangjiang,Guangdong Province are determined using the double-difference earthquake location algorithm(DDA).The seismicity pattern becomes concentrated from discrete grids.The ... The locations of about 400 earthquakes in Yangjiang,Guangdong Province are determined using the double-difference earthquake location algorithm(DDA).The seismicity pattern becomes concentrated from discrete grids.The rupture characteristics of the Yangjiang earthquake sequence show a conjugated distribution in NW and NE directions.The major distribution trends NE and dips NE with an angle of 30° and a length of 30km,and the minor distribution trends NW and dips SE with an angle of 30° and a length of 20km.The focal depth is 5km~15km.The distribution of the Enping earthquake sequence,which is not far from Yangjiang,is NW-trending.The relationship between hypocenter distribution and geological structure is discussed. 展开更多
关键词 地震位置 活动度 断层移动 探测方法
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EXISTENCE AND ATTRACTIVITY OF k-ALMOST AUTOMORPHIC SEQUENCE SOLUTION OF A MODEL OF CELLULAR NEURAL NETWORKS WITH DELAY 被引量:3
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作者 Syed ABBAS 夏永辉 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期290-302,共13页
In this paper we discuss the existence and global attractivity of k-almost automorphic sequence solution of a model of cellular neural networks. We consider the corresponding difference equation analogue of the model ... In this paper we discuss the existence and global attractivity of k-almost automorphic sequence solution of a model of cellular neural networks. We consider the corresponding difference equation analogue of the model system using suitable discretization method and obtain certain conditions for the existence of solution. Almost automorphic function is a good generalization of almost periodic function. This is the first paper considering such solutions of the neural networks. 展开更多
关键词 almost automorphic sequence difference equations neural networks
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Ordovician sequence stratigraphy and correlation in the Middle-Upper Yangtze region,South China 被引量:3
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作者 Chuan-shang Wang Xiao-feng Wang +2 位作者 Xiao-hong Chen Zhi-hong Li Xu-bing Li 《China Geology》 2018年第3期354-366,共13页
The precise correlation of the Ordovician successions in different facies is difficult due to the complex changes of the tecto-paleogeography in South China.Based on previous studies,the authors recognized 103rd grade... The precise correlation of the Ordovician successions in different facies is difficult due to the complex changes of the tecto-paleogeography in South China.Based on previous studies,the authors recognized 103rd grade sequences,i.e.,Osq1 to Osq10 in ascending order,by the integrated study of chronostratigraphy,biostratigraphy as well as the analysis on the sedimentary facies.The authors are confident to correlate the Ordovician successions precisely in different facies in an isochronous stratigraphic framework with the application of the method of sequence stratigraphy and correlation. 展开更多
关键词 sequence STRATIGRAPHY CORRELATION different FACIES ORDOVICIAN
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Constructions for almost perfect binary sequence pairs with even length 被引量:1
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作者 PENG Xiuping LIN Hongbin +1 位作者 REN Jiadong1 CHEN Xiaoyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期256-261,共6页
The concept of the binary sequence pair is generalized from a single binary sequence. Binary sequence pairs are applied in many fields of radar, sonar or communication systems, in which signals with optimal periodic c... The concept of the binary sequence pair is generalized from a single binary sequence. Binary sequence pairs are applied in many fields of radar, sonar or communication systems, in which signals with optimal periodic correlation are required. Several types of almost perfect binary sequence pairs of length T = 2q are constructed, where q is an odd number. These almost perfect binary sequence pairs are based on binary ideal sequence or binary ideal two-level correlation sequence pairs by using Chinese remainder theorem. For these almost perfect binary sequence pairs with good balanced property, their corresponding divisible difference set pairs(DDSPs) are also derived. 展开更多
关键词 sequence design divisible difference set pair(DDSP) binary sequence pair almost perfect
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The 20 April 2013 Lushan, Sichuan, mainshock, and its aftershock sequence: tectonic implications 被引量:21
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作者 Jianshe Lei Guangwei Zhang Furen Xie 《Earthquake Science》 2014年第1期15-25,共11页
Using the double-difference relocation algo- rithm, we relocated the 20 April 2013 Lushan, Sichuan, earthquake (Ms 7.0), and its 4,567 aftershocks recorded during the period between 20 April and May 3, 2013. Our res... Using the double-difference relocation algo- rithm, we relocated the 20 April 2013 Lushan, Sichuan, earthquake (Ms 7.0), and its 4,567 aftershocks recorded during the period between 20 April and May 3, 2013. Our results showed that most aftershocks are relocated between 10 and 20 km depths, but some large aftershocks were relocated around 30 krn depth and small events extended upward near the surface. Vertical cross sections illustrate a shovel-shaped fault plane with a variable dip angle from the southwest to northeast along the fault. Furthermore, the dip angle of the fault plane is smaller around the mainshock than that in the surrounding areas along the fault. These results suggest that it may be easy to generate the strong earthquake in the place having a small dip angle of the fault, which is somewhat similar to the genesis of the 2008 Wenchuan earthquake. The Lushan mainshock is underlain by the seismically anomalous layers with low-Vp, low-Vs, and high-Poisson's ratio anomalies, possibly suggesting that the fluid-filled fractured rock matrices might signifi- cantly reduce the effective normal stress on the fault plane to bring the brittle failure. The seismic gap between Lushan and Wenchuan aftershocks is suspected to be vulnerable to future seismic risks at greater depths, if any. 展开更多
关键词 Lushan mainshock Aftershock sequence Double-difference algorithm - Shovel-shaped structure Variable dip angle
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PERIODIC COMPLEMENTARY BINARY SEQUENCE PAIRS 被引量:16
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作者 XuChengqian ZhaoXiaoqun 《Journal of Electronics(China)》 2002年第2期152-159,共8页
A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the proper... A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the properties and existing conditions of PCSP and the recursive constructions for PCSP are given. 展开更多
关键词 编码理论 程序块设计 自相关函数 二元序列
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PROPERTIES OF SOME SETS OF SEQUENCES DEFINED BY A MODULUS FUNCTION
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作者 Yavuz Altin 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期427-434,共8页
In this article, the author introduces the generalized difference paranormed sequence spaces c (△v^m, f, p, q, s), c0 (△v^m, f, p, q, s), and l∞ (△v^m, f, p, q, s) defined over a seminormed sequence space (... In this article, the author introduces the generalized difference paranormed sequence spaces c (△v^m, f, p, q, s), c0 (△v^m, f, p, q, s), and l∞ (△v^m, f, p, q, s) defined over a seminormed sequence space (X, q). The author also studies their properties like completeness, solidity, symmetricitv, etc. 展开更多
关键词 difference sequence modulus function SEMINORM
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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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Hájek-Rényi-type Inequality for a Class of Random Variable Sequences and Its Applications
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作者 WANG XUE-JUN SHEN YAN HU SHU-HE YANG WEN-ZHI 《Communications in Mathematical Research》 CSCD 2011年第1期6-16,共11页
In this paper, we obtain the Hejek-Renyi-type inequality for a class of random variable sequences and give some applications for associated random variable sequences, strongly positive dependent stochastic sequences a... In this paper, we obtain the Hejek-Renyi-type inequality for a class of random variable sequences and give some applications for associated random variable sequences, strongly positive dependent stochastic sequences and martingale difference sequences which generalize and improve the results of Prakasa Rao and Soo published in Statist. Probab. Lett., 57(2002) and 78(2008). Using this result, we get the integrability of supremum and the strong law of large numbers for a class of random variable sequences. 展开更多
关键词 Hajek-Renyi-type inequality associated random variable sequence strongly positive dependent stochastic sequence martingale difference sequence
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