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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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DNA Sequences with Forbidden Words and the Generalized Cantor Set
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作者 Zhuowei Yang Ping Wang 《Journal of Applied Mathematics and Physics》 2019年第8期1687-1696,共10页
In this work, we establish relations between DNA sequences with missing subsequences (the forbidden words) and the generalized Cantor sets. Various examples associated with some generalized Cantor sets, including Hao... In this work, we establish relations between DNA sequences with missing subsequences (the forbidden words) and the generalized Cantor sets. Various examples associated with some generalized Cantor sets, including Hao’s frame representation and the generalized Sierpinski Set, along with their fractal graphs, are also presented in this work. 展开更多
关键词 DNA sequenceS GENERALIZED CANTOR set
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Lacunary Invariant Statistical Convergence Of Sequences Of Sets With Respect To A Modulus Function
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作者 Nimet Pancaroglu Fatih Nuray 《Journal of Mathematics and System Science》 2015年第3期122-126,共5页
In this paper, we introduce and study the concept of lacunary invariant convergence for sequences of sets with respect to modulus functionfand give some inclusion relations.
关键词 Statistical convergence lacunary invariant convergence sequences of sets modulus function
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Devonian Sequence Stratigraphy and Relative Sea Level Changes in Longmenshan Area, Sichuan 被引量:5
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作者 Liu Wenjun Chen Yuanren Zheng Rongcai Wang Hongfeng Li Xianghui (Chengdu Institute of Technology, Chengdu 610059) 《Journal of Earth Science》 SCIE CAS CSCD 1996年第1期80-86,共7页
The Longmenshan area is located at the western margin of Yangtze platform, where the Devonian is composed of clastic rocks, mixed clastic-carbonate rocks and carbonate rocks in ascending order, and was formed in the m... The Longmenshan area is located at the western margin of Yangtze platform, where the Devonian is composed of clastic rocks, mixed clastic-carbonate rocks and carbonate rocks in ascending order, and was formed in the marine environment from nearshore to outer shelf. Based on a study of six sections the Devonian in Longemenshan area is divided into 18 sequences and 5 sequence sets. The maximum transgressive high in the Devonian of this area occurred in Early Frasnian, corresponding to asymmetricus zone. The boundaries among the sequence sets are roughly corresponding to the bottom boundaries of Ⅰa',Ⅰc',Ⅱa, and Ⅱd in the Devonian of West Europe and North America, respectively. The frequencies of the relative sea level changes in this area vary in different periods, but can be correlated with those in the other regions of the world. 展开更多
关键词 Devonian sequence sequence set Yangtze platform Longmenshan area.
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Simulated annealing algorithm for the optimal translation sequence of the jth agent in rough communication 被引量:5
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作者 Wang Hongkai Guan Yanyong Xue Peijun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期507-512,共6页
In rough communication, because each agent has a different language and cannot provide precise communication to each other, the concept translated among multi-agents will loss some information and this results in a le... In rough communication, because each agent has a different language and cannot provide precise communication to each other, the concept translated among multi-agents will loss some information and this results in a less or rougher concept. With different translation sequences, the problem of information loss is varied. To get the translation sequence, in which the jth agent taking part in rough communication gets maximum information, a simulated annealing algorithm is used. Analysis and simulation of this algorithm demonstrate its effectiveness. 展开更多
关键词 rough sets rough communication translation sequence OPTIMAL simulated annealing algorithm.
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Sequence Stratigraphy of the Palaeogene in the HGZ Area of Qaidam Basin 被引量:2
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作者 Wu Yinye Hou Yu'an +1 位作者 Guo Bincheng Cui Huajuan 《Petroleum Science》 SCIE CAS CSCD 2007年第3期14-20,30,共8页
Sequence stratigraphy can be used to predict the oil and gas reservoir bodies and to choose the oil targets. Fan delta and sublacustrine fan systems are developed in the HGZ Area, which is located in front of the Altu... Sequence stratigraphy can be used to predict the oil and gas reservoir bodies and to choose the oil targets. Fan delta and sublacustrine fan systems are developed in the HGZ Area, which is located in front of the Altun Mountain in the west of the Qaidam Basin. On the basis of seismic and well drilling data, the deposits in the area were studied by using sequence stratigraphy and reservoir prediction techniques. Various reservoir prediction techniques used under the constraint of high resolution sequence framework could help to improve the precision of reservoir prediction and to recognize the pinch out line of sand layers, the distribution of isolated sandstone bodies and the types of oil pools. The study of sequence stratigraphy makes reservoir prediction more effective by dividing different scales of sequences and distinguishing the system tracts and parasequence sets, and indicates the internal relationship between oil/gas and sedimentary bodies in different system tracts with evolution in time and space. 展开更多
关键词 sequence stratigraphy RESERVOIR systems tract parasequence sets exploration targets Qaidam Basin
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Sequence Stratigraphy and Relative Sea Level Changes in Sinian System of Yichang, Hubei Province 被引量:2
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作者 Wang Ziqiang (Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083) Gao Linzhi (Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037) Zhang Linghua Jiang Ganqing Zhang Chuanheng Yin Yong (Dep 《Journal of Earth Science》 SCIE CAS CSCD 1996年第1期29-37,共9页
The study on outcrop sequence stratigraphy of the Sinian section in the Yangtze Gorges an important step in the comprehensive stratigraphy for the Sinian stratotype. In this paper, the base of the Nantuo tillite is se... The study on outcrop sequence stratigraphy of the Sinian section in the Yangtze Gorges an important step in the comprehensive stratigraphy for the Sinian stratotype. In this paper, the base of the Nantuo tillite is selected as the bottom boundary of the Sinian, and the top of the Baimatuo Member of the Dengying Formation is taken as the top boundary. The Sinian lasted from 740 the to 570 Ma. According to the features of sequence boundary facies and the parasequence sets, two supersequences are recognized in the Sinian with six sequences. In this paper, the authors discuss the correlation of those sequences. On the basis of the subsidence rate and the thickness of decompressed deposits, the authors discuss the mechanism of tectonic and sedimentation of the Dengying Formation and the features of high-frequency rhythms as well as the 3rd-order sequences in the Yangtze Gorges. 展开更多
关键词 Sinian System sequence supersequence stacking parasequence set.
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Constructions for almost perfect binary sequence pairs with even length 被引量:2
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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 Linear Span of a Class of Optimal Frequency Hopping Sequences 被引量:1
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作者 高军涛 胡予濮 李雪莲 《China Communications》 SCIE CSCD 2011年第2期147-151,共5页
For the anti-jamming purpose,frequency hopping sequences are required to have a large linear span. In this paper,we firstly give the linear span of a class of optimal frequency hopping sequences. The results show that... For the anti-jamming purpose,frequency hopping sequences are required to have a large linear span. In this paper,we firstly give the linear span of a class of optimal frequency hopping sequences. The results show that the linear span is very small compared with their periods. To improve the linear span,we transform these optimal frequency hopping sequences into new optimal frequency hopping sequences with large linear span by using a general type of permutation polynomials over a finite field. Furthermore,we give the exact values of the linear span of the transformed optimal frequency hopping sequences. 展开更多
关键词 frequency hopping sequences linear span permutation polynomials optimal sets
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Ground state energy of He isoelectronic sequence treated variationally via Hylleraas-like wavefunction
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作者 Serpil Sakiroglu Kadir Akgngr Ismail Skmen 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2238-2243,共6页
In this study, the energy for the ground state of helium and a few helium-like ions (Z=1-6) is computed variationally by using a Hylleraas-like wavefunction. A four-parameters wavefunction, satisfying boundary condi... In this study, the energy for the ground state of helium and a few helium-like ions (Z=1-6) is computed variationally by using a Hylleraas-like wavefunction. A four-parameters wavefunction, satisfying boundary conditions for coalescence points, is combined with a Hylleraas-like basis set which explicitly incorporates r12 interelectronic distance. The main contribution of this work is the introduction of modified correlation terms leading to the definition of integral transforms which provide the calculation of expectation value of energy to be done analytically over single-particle coordinates instead of Hylleraas coordinates. 展开更多
关键词 He isoelectronic sequence Hylleraas basis set electronic correlation variational method
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Sequences and Limits
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作者 Wolfgang Mueckenheim 《Advances in Pure Mathematics》 2015年第2期59-61,共3页
It is widely held that irrational numbers can be represented by infinite digit-sequences. We will show that this is not possible. A digit sequence is only an abbreviated notation for an infinite sequence of rational p... It is widely held that irrational numbers can be represented by infinite digit-sequences. We will show that this is not possible. A digit sequence is only an abbreviated notation for an infinite sequence of rational partial sums. As limits of sequences, irrational numbers are incommensurable with any grid of decimal fractions. 展开更多
关键词 Series sequenceS Limits DEFINABILITY of REAL NUMBERS set THEORY
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Integral Sequences of Infinite Length Whose Terms Are Relatively Prime
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作者 Kazuyuki Hatada 《Advances in Pure Mathematics》 2013年第1期24-28,共5页
It is given in Weil and Rosenlicht ([1], p. 15) that (resp. 2) for all non-negative integers m and n with m≠n if c is any even (resp. odd) integer. In the present paper we generalize this. Our purpose is to give othe... It is given in Weil and Rosenlicht ([1], p. 15) that (resp. 2) for all non-negative integers m and n with m≠n if c is any even (resp. odd) integer. In the present paper we generalize this. Our purpose is to give other integral sequences such that G.C.D.(ym,yn)=1 for all positive integers m and n with m≠n. Roughly speaking we show the following 1) and 2). 1) There are infinitely many polynomial sequences such that G.C.D.(fm(a),fn(a))=1 for all positive integers m and n with with m≠n and infinitely many rational?integers a. 2) There are polynomial sequences such that G.C.D.(gm(a,b),gn(a,b))=1 for all positive integers m and n with m≠n and arbitrary (rational or odd) integers a and b with G.C.D.(a,b)=1. Main results of the present paper are Theorems 1 and 2, and Corollaries 3, 4 and 5. 展开更多
关键词 Relatively PRIME INTEGRAL sequenceS of INFINITE LENGTH sets of INFINITELY Many PRIME Numbers
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Positional Information Storage in Sequence Patterns
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作者 Alexey A. Shadrin Andrei Grigoriev Dmitri V. Parkhomchuk 《Computational Molecular Bioscience》 2013年第2期18-26,共9页
We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of... We build a model of storage of well-defined positional information in probabilistic sequence patterns. Once a pattern is defined, it is possible to judge the effect of any mutation in it. We show that the frequency of beneficial mutations can be high in general and the same mutation can be either advantageous or deleterious depending on the pattern’s context. The model allows to treat positional information as a physical quantity, formulate its conservation law and to model its continuous evolution in a whole genome, with meaningful applications of basic physical principles such as optimal efficiency and channel capacity. A plausible example of optimal solution analytically describes phase transitions-like behavior. The model shows that, in principle, it is possible to store error-free information on sequences with arbitrary low conservation. The described theoretical framework allows one to approach from novel general perspectives such long-standing paradoxes as excessive junk DNA in large genomes or the corresponding G- and C-values paradoxes. We also expect it to have an effect on a number of fundamental concepts in population genetics including the neutral theory, cost-of-selection dilemma, error catastrophe and others. 展开更多
关键词 INFORMATION Theory sequence Pattern GENETIC INFORMATION CONSERVATION TYPICAL set
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Genetic algorithm forλ-optimal translation sequence of rough communication
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作者 Hongkai Wang Yanyong Guan Chunhua Yuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期609-614,共6页
In rough communication,because each agent has a different language and can not provide precise communication to each other,the concept translated among multi-agents will loss some information,and this results in a les... In rough communication,because each agent has a different language and can not provide precise communication to each other,the concept translated among multi-agents will loss some information,and this results in a less or rougher concept.With different translation sequences the amount of the missed knowledge is varied.Theλ-optimal translation sequence of rough communication,which concerns both every agent and the last agent taking part in rough communication to get information as much as he(or she)can,is given.In order to get theλ-optimal translation sequence,a genetic algorithm is used.Analysis and simulation of the algorithm demonstrate the effectiveness of the approach. 展开更多
关键词 rough sets rough communication λ-optimal trans-lation sequence genetic algorithm.
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Characteristics of Dengying Fm sedimentary sequence in the central-western Sichuan Basin and their controlling effect on gas accumulation 被引量:1
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作者 Wen Long Yang Yueming +5 位作者 You Chuanqiang Zhang Xihua Peng Hanlin Wang Wenzhi Luo Bing Luo Wenjun 《Natural Gas Industry B》 2016年第5期428-438,共11页
A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area,central Sichuan Basin.In order to promote the oil and gas exploration in this area,it is of great significance to sustainably deepe... A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area,central Sichuan Basin.In order to promote the oil and gas exploration in this area,it is of great significance to sustainably deepen the analysis on its high-quality reservoir distribution and sourcereservoir assemblage.In this paper,a series of studies were performed on the sequence frameworks and sedimentary filling evolution characteristics of the Dengying Fm in centralewestern Sichuan Basin,and their controlling effects on the reservoir development and distribution and source-reservoir assemblage during its sedimentation.It is shown that the Deyang-Anyue paleo-rift is,on the whole,distributed in a NW direction,and is morphologically wide and steep in the north,but narrow and gentle in the south.There are two rift boundaries of the second and fourth members of Dengying Fm(Deng 2 Member and Deng 4 Member,respectively).The rift of Deng 2 Member is distributed in the shape of“U”in Deyang-Neijiang area.Dengying Fm is divided into four third-order sequences(SQ1-SQ4).In SQ3 of Gaoshiti-Moxi area,central Sichuan Basin,a complete sedimentation reflection structure of transgressive overlap and regressive progradation can be identified with earlyemiddle Deng 4 Member platform margin.The paleo-rift was in embryo before the sedimentation of Sinian,so the sedimentary filling and lithofacies distribution of the Sinian were influenced by the inherited activities of pre-Sinian rifts.The favorable distribution zones of highquality reservoirs are located at the rift margins of Deng 2 and Deng 4 Members that were formed respectively during the SQ2 and SQ4 and the platform margin of early Deng 4 Member that was formed during the SQ3.A laterally connected source-reservoir assemblage occurs at the margins of Deng 2 and Deng 4 Members around the Lower Cambrian source rocks of the paleo-rift.The northwestward extending margin zone along the eastern flank of the paleo-rift shows a good potential for hydrocarbon accumulation. 展开更多
关键词 Sichuan basin SINIAN Gas accumulation Sedimentary structure setting Stratigraphic sequence Sedimentary filling RESERVOIRS Source-reservoir assemblage Controlling factors
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ON CHANNEL ESTIMATION USING OPTIMAL TRAINING SEQUENCES IN CYCLIC-PREFIX-BASED SINGLE-CARRIER SYSTEMS WITH SPACE-TIME BLOCK-CODING
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作者 Yuan Weina Wang Ping Fan Pingzhi 《Journal of Electronics(China)》 2008年第1期28-31,共4页
In this paper, a new scheme that combines Space-Time Block-Coding (STBC) based on an Alamouti-like scheme and the Least Squares (LS) channel estimation using optimal training sequences in Cyclic-Prefix-based (CP)\Sing... In this paper, a new scheme that combines Space-Time Block-Coding (STBC) based on an Alamouti-like scheme and the Least Squares (LS) channel estimation using optimal training sequences in Cyclic-Prefix-based (CP)\Single-Carrier (SC) systems is proposed. With two transmit antennas, based on Cramer-Rao lower bound for channel estimation, it is shown that the Periodic Comple- mentary Set (PCS) is optimal over frequency-selective fading channels. Compared with the normal scheme without STBC, 3dB Mean Square Error (MSE) performance gains and fewer restrictions on the length of channel impulse response are demonstrated. 展开更多
关键词 Optimal training sequences Channel estimation Periodic Complementary set (PCS) Space-Time Block-Coding (STBC)
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New method for constructing array sets with zero-correlation zone 被引量:1
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作者 Xiaoyu Chen Chengqian Xu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期925-930,共6页
A new method to construct shift sequence sets is presented. Different shift sequence sets are obtained by changing parameters of the shift sequence. Based on these shift sequence sets, multiple shift distinct array se... A new method to construct shift sequence sets is presented. Different shift sequence sets are obtained by changing parameters of the shift sequence. Based on these shift sequence sets, multiple shift distinct array sets with zero-correlation zone (ZCZ) can be obtained by utilizing interleaving technique. It is shown that the resultant ZCZ array sets are optimal or almost optimal with respect to the Tang, Fan, and Matsufuji bound. Compared with previous methods, the proposed method extends the number of shift distinct ZCZ array sets. 展开更多
关键词 array set interleaving technique shift sequence zerocorrelation zone (ZCZ)
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Machine intelligence,rough sets and rough-fuzzy granular computing:uncertainty handling in bio-informatics and Web intelligence
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作者 Sankar K Pal 《重庆邮电大学学报(自然科学版)》 北大核心 2010年第6期720-723,760,共5页
Machine intelligence,is out of the system by the artificial intelligence shown.It is usually achieved by the average computer intelligence.Rough sets and Information Granules in uncertainty management and soft computi... Machine intelligence,is out of the system by the artificial intelligence shown.It is usually achieved by the average computer intelligence.Rough sets and Information Granules in uncertainty management and soft computing and granular computing is widely used in many fields,such as in protein sequence analysis and biobasis determination,TSM and Web service classification Etc. 展开更多
关键词 machine intelligence rough sets information granules rough-fuzzy case generation protein sequence analysis and biobasis determination TSM web service classification
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Infinite Sets of Solutions and Almost Solutions of the Equation <i>N</i>&sdot;<i>M</i>= reversal(<i>N</i>&sdot;<i>M</i>)
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作者 Viorel Niţ ică Premalata Junius 《Open Journal of Discrete Mathematics》 2019年第3期63-67,共5页
Motivated by their intrinsic interest and by applications to the study of numeric palindromes and other sequences of integers, we discover infinite sets of solutions and almost solutions of the equation N?&sdot;?M... Motivated by their intrinsic interest and by applications to the study of numeric palindromes and other sequences of integers, we discover infinite sets of solutions and almost solutions of the equation N?&sdot;?M=reversal (N?&sdot;M). Most of our results are valid in a general numeration base. 展开更多
关键词 sequences of INTEGERS Infinite sets
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RELATIVELY WEAKLY COMPACT SETS IN THE DENJOY SPACE
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作者 Bongiorno Benedetto(Department of Mathematics, Via Archirafiy490123 Palermo ITALY) 《数学研究》 CSCD 1994年第1期37-44,共8页
RELATIVELYWEAKLYCOMPACTSETSINTHEDENJOYSPACE¥BongiornoBenedetto(DepartmentofMathematics,ViaArchirafiy490123Pa... RELATIVELYWEAKLYCOMPACTSETSINTHEDENJOYSPACE¥BongiornoBenedetto(DepartmentofMathematics,ViaArchirafiy490123PalermoITALY)Abstra... 展开更多
关键词 Denjoy空间 相关弱紧集 渐进等连续序列 亨斯托克积分函数
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