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Seismic identification and characterization of complex storage space oil and gas reservoirs
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作者 XiaoYu-Jiang Tao Song +5 位作者 Li Deng-Gan Xiao Yue-Zhou Jing Liang Lele-Wei Ming Zhang Xiaofeng-Dai 《Applied Geophysics》 SCIE CSCD 2024年第3期606-615,620,共11页
To predict complex reservoir spaces(with developed caves,pores,and fractures),based on the results of full-azimuth depth migration processing,we adopted reverse weighted nonlinear inversion to improve the accuracy of ... To predict complex reservoir spaces(with developed caves,pores,and fractures),based on the results of full-azimuth depth migration processing,we adopted reverse weighted nonlinear inversion to improve the accuracy of porous reservoir prediction.Scattering imaging three-parameter wavelet transform technology was used to accurately predict small-scale cave bodies.The joint inversion method of velocity and amplitude anisotropy was developed to improve the accuracy of small and medium-sized fracture prediction.The results of multiscale fracture modeling and characterization,interwell connectivity analysis,and connection path prediction are consistent with the production condition.Finally,based on the above prediction findings,favorable reservoir development areas were predicted.The above ideas and strategies have great application value for the efficient exploration and development of complex storage space reservoirs and the optimization of high-yield well locations. 展开更多
关键词 complex storage space fracture prediction reservoir prediction cave prediction
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High complex anal fistula managed by the modified transanal opening of the intersphincteric space via the inter-sphincteric approach:A case report
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作者 Ya-Qun Wang Yan Wang +2 位作者 Xiao-Feng Jia Qiao-Jing Yan Xue-Ping Zheng 《World Journal of Radiology》 2024年第10期552-560,共9页
BACKGROUND High complex anal fistulas are epithelialized tunnels,with the main fistula piercing above the deep external sphincter and the internal opening approaching the dentate line.Conventional surgical procedures ... BACKGROUND High complex anal fistulas are epithelialized tunnels,with the main fistula piercing above the deep external sphincter and the internal opening approaching the dentate line.Conventional surgical procedures for high complex anal fistulas remove most of the external sphincter and damage the anorectal ring.Postoperative loss of anal function can cause physical and mental damage.Transanal opening of the intersphincteric space(TROPIS)is an effective procedure that completely preserves the external anal sphincter.However,its clinical application is limited by challenges in the localization of the internal opening of a fistula and the high risk of complications.On the basis of our clinical experience,we modified the TROPIS procedure for the treatment of treating high complex anal fistulas.CASE SUMMARY A patient with a high complex anal fistula located above the anorectal ring underwent modified TROPIS,which involved sepsis drainage and identification of the internal opening in the intersphincteric space.The patient with the high complex anal fistula recovered well postoperatively,without any postoperative complications or anal dysfunction.Anal function returned to normal after 17 months of follow-up.CONCLUSION The modified TROPIS procedure is the most minimally invasive surgery for anal fistulas that minimally impairs anal function.It allows the complete removal of infected anal glands and reduces the risk of postoperative complications.Modified TROPIS via the intersphincteric approach is an alternative sphincter-preserving treatment for high complex anal fistulas. 展开更多
关键词 High complex anal fistula Inter-sphincteric infection Trans-anal opening of inter-sphincteric space PERIANAL Pelvic magnetic resonance imaging Anal function protection Case report
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Motion and Special Relativity in Complex Spaces
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 Special Relativity complex space and Time Models and Dramatic SR Simplification complex Time and space Separation complex Time Interpretation
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THE FEKETE-SZEG?INEQUALITY AND SUCCESSIVE COEFFICIENTS DIFFERENCE FOR A SUBCLASS OF CLOSE-TO-STARLIKE MAPPINGS IN COMPLEX BANACH SPACES 被引量:1
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作者 徐庆华 方炜康 +1 位作者 冯伟珩 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2075-2088,共14页
Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 fo... Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 for close-to-convex functions.Now we generalized the above conclusions to a subclass of close-to-starlike mappings defined on the unit ball of a complex Banach space. 展开更多
关键词 Fekete and Szego inequality successive coefficients difference bound close-to-starlike mappings complex Banach space
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An experimental study on fire characteristics of urban complex underground space based on BIM
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作者 Jinrong Cui Hao Mei +3 位作者 Haosen Sun Ye Jingqi Wei Hu Yong Xu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1403-1414,共12页
Compared with the space on the ground,if there is a fire in the urban complex underground space,the loss will be greatly harmful.In addition,the complex underground space is usually connected with other large space ar... Compared with the space on the ground,if there is a fire in the urban complex underground space,the loss will be greatly harmful.In addition,the complex underground space is usually connected with other large space areas and densely populated.Once a fire occurs in the complex underground space,it will cause huge property losses and casualties.In order to reduce the risk of fire,it is necessary to deeply understand the development rules and characteristics of fire in the complex underground space of the city.This article has mainly carried on the following work:(I)A particularly complex model of the multi‐storey subway station was built.On this basis,three groups of comparative experiments were conducted to study the effects of fire power,fire location and smoke control system on fire development,and the conclusion that fire location is the most important factor for fire development was obtained;(II)In order to explore the entire space fire and the local space fire,CFD(Computational Fluid Dynamics)is used to build a large‐size fire model and a small‐size fire model respectively;(III)Multiple detector data as temperature slices were built,and it is expected to make full use of the simulation data to deduce the important index of fire location in the early stage of fire.All of the works in this paper will provide reference experimental data for the prevention and firefighting of a sudden fire in the complex underground space. 展开更多
关键词 fire simulation underground multi‐storey subway station urban complex underground space
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Design Strategy of Underground Space of Urban Rail Transit Complex Based on Integration Concept
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作者 YU Fei 《Journal of Landscape Research》 2023年第1期31-35,共5页
With the accelerated development and utilization of urban underground space,the underground space design of complex based on rail transit has attracted much attention.By sorting out the integration concept and constru... With the accelerated development and utilization of urban underground space,the underground space design of complex based on rail transit has attracted much attention.By sorting out the integration concept and constructing the logical framework of integrated design,the integrated design strategy is proposed from the aspects of function,transportation,space and environment on the urban scale,and the evaluation points of integrated design effect are put forward from the aspects of accessibility,coordination,openness and symbolism. 展开更多
关键词 INTEGRATION Rail transit complex Underground space Design strategy
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Evolving patterns of agricultural production space in China:A network-based approach
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作者 Shuhui Yang Zhongkai Li +2 位作者 Jianlin Zhou Yancheng Gao Xuefeng Cui 《Geography and Sustainability》 CSCD 2024年第1期121-134,共14页
The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have p... The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological analysis.In this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in China.The results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past decades.The little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively stable.Additionally,identified provincial communities closely resemble China's agricultural natural zones.Furthermore,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural production.Despite the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special attentions.The findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development. 展开更多
关键词 Agricultural system complex network Agricultural production space Proximity matrix Production capability
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基于CiteSpace的商业综合体公共空间研究现状综述
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作者 刘洋 刘彤彤 《建筑与文化》 2024年第1期147-149,共3页
随着城市化进程的不断推进,城市居民生活逐渐由物质层面向精神层面延伸。为满足城市商业发展和消费者对商业空间的多元化需求,商业综合体公共空间研究成为重要方面。文章基于中国知网(CNKI)数据库,整理相关文献,运用CiteSpace知识图谱... 随着城市化进程的不断推进,城市居民生活逐渐由物质层面向精神层面延伸。为满足城市商业发展和消费者对商业空间的多元化需求,商业综合体公共空间研究成为重要方面。文章基于中国知网(CNKI)数据库,整理相关文献,运用CiteSpace知识图谱量化文献计量软件,总结2005—2023年该领域发文量变化、关键词及聚类图谱等要素,对该领域的研究趋势进行分析,以期为商业综合体公共空间设计提供参考。 展开更多
关键词 CITEspace 商业综合体 公共空间 研究综述
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SLANT IMMERSIONS OF COMPLEX SPACE FORMS AND CHEN'S INEQUALITY 被引量:10
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作者 李光汉 吴传喜 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期223-232,共10页
A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the sla... A submanifold in a complex space form is called slant if it has constant Wirtinger angles. B. Y. Chen and Y. Tazawa proved that there do not exist minimal proper slant surfaces in CP2 and CH2. So it seems that the slant immersion has some interesting properties. The authors have great interest to consider slant immersions satisfying some additional conditions, such as unfull first normal bundles or Chen’s equality holding. They prove that there do not exist n-dimensional Kaehlerian slant immersions in CPn and CHn with unfull first normal bundles. Next, it is seen that every Kaehlerian slant submanifold satisfying an equality of Chen is minimal which is similar to that of Lagrangian immersions. But in contrast, it is shown that a large class of slant immersions do not exist thoroughly. Finally, they give an application of Chen’s inequality to general slant immersions in a complex projective space, which generalizes a result of Chen. 展开更多
关键词 Slant immersion IDEAL Chen's inequality complex space form
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The influence of pore structure on P-& S-wave velocities in complex carbonate reservoirs with secondary storage space 被引量:10
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作者 Wang Haiyang Sam Zandong Sun +3 位作者 Yang Haijun Gao Hongliang Xiao Youjun Hu Hongru 《Petroleum Science》 SCIE CAS CSCD 2011年第4期394-405,共12页
Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary stora... Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary storage space shape influences the P-& S-wave velocities (or elastic properties) in complex carbonate reservoirs.In this paper,three classical rock physics models (Wyllie timeaverage equation,Gassmann equation and the Kuster-Toks z model) are comparably analyzed for their construction principles and actual velocity prediction results,aiming at determining the most favourable rock physics model to consider the influence of secondary storage space shape.Then relationships between the P-& S-wave velocities in carbonate reservoirs and geometric shapes of secondary storage spaces are discussed from different aspects based on actual well data by employing the favourable rock physics model.To explain the influence of secondary storage space shape on V P-V S relationship,it is analyzed for the differences of S-wave velocities between derived from common empirical relationships (including Castagna's mud rock line and Greenberg-Castagna V P-V S relationship) and predicted by the rock physics model.We advocate that V P-V S relationship for complex carbonate reservoirs should be built for different storage space types.For the carbonate reservoirs in the Tarim Basin,the V P-V S relationships for fractured,fractured-cavernous,and fractured-hole-vuggy reservoirs are respectively built on the basis of velocity prediction and secondary storage space type determination.Through the discussion above,it is expected that the velocity prediction and the V P-V S relationships for complex carbonate reservoirs should fully consider the influence of secondary storage space shape,thus providing more reasonable constraints for prestack inversion,further building a foundation for realizing carbonate reservoir prediction and fluid prediction. 展开更多
关键词 complex carbonate reservoir secondary storage space velocity prediction V P-V S relationships
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Some remarks on pseudo-umbilical totally real submanifolds in a complex projective space 被引量:3
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作者 ZHANG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第2期227-232,共6页
This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-... This paper studies the relationship between the pseudo-umbilical totally real submanifolds and the minimal totally real submanifolds in a complex projective space. Two theo- rems which claim that some types of pseudo-umbilical totally real submanifolds must be minimal submanifolds are proved. 展开更多
关键词 complex projective space totally real submanifold pseudo-umbilical submanifold minimal submanifold.
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B-Implicit Contractive Conditions and Unique(Common) Fixed Points on Complex Valued Metric Spaces 被引量:2
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作者 PIAO Yong-jie 《Chinese Quarterly Journal of Mathematics》 2018年第2期212-220,共9页
A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed... A class B of complex functions is introduced and several existence theorems of unique(common) fixed points for mappings satisfying a B-implicit contraction are presented.Moreover, the existence results of common fixed points for two mappings on a nonempty set with two complex valued metrics are provided. Our outcomes generalize and improve some known results, especially, for instance, Banach contraction principle, Chatterjea-type fixed point theorem and the corresponding fixed point theorems. 展开更多
关键词 complex valued metric space (Common) Fixed point B-implicit contraction
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One Roper-Suffridge Extension Operator in Complex Banach Spaces 被引量:1
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作者 WANG Xiao-feng XU Yi-fei 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期468-474,共7页
In this paper, by the definition of almost spirallike mappings of type β and order α and the geometric property of the spirallike mapping of type β, we prove that the generalized Roper-Suffridge extension operator ... In this paper, by the definition of almost spirallike mappings of type β and order α and the geometric property of the spirallike mapping of type β, we prove that the generalized Roper-Suffridge extension operator preserves almost spirallikeness of type β and order α in complex Banach spaces. Key words: 展开更多
关键词 Roper-Suffridge extension operator Reinhardt domains complex Banach spaces
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SPACES OF ANALYTIC FUNCTIONS REPRESENTED BY DIRICHLET SERIES OF TWO COMPLEX VARIABLES 被引量:1
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作者 Hazem Shaba Behnam and G. S. Srivastava (Indian Institule Technology of Roorkee, India) 《Approximation Theory and Its Applications》 2002年第3期1-14,共14页
We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the auth... We consider the space X of all analytic functionsof two complex variables s1 and s2, equipping it with the natural locally convex topology and using the growth parameter, the order of f as defined recently by the authors. Under this topology X becomes a Frechet space Apart from finding the characterization of continuous linear functionals, linear transformation on X, we have obtained the necessary and sufficient conditions for a double sequence in X to be a proper bases. 展开更多
关键词 spaceS OF ANALYTIC FUNCTIONS REPRESENTED BY DIRICHLET SERIES OF TWO complex VARIABLES TEB MATH
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COMPLEX SYMMETRY OF TOEPLITZ OPERATORS OVER THE BIDISK 被引量:2
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作者 王茂发 吴奇 韩凯凯 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1537-1546,共10页
In this paper,we investigate the complex symmetric structure of Toeplitz operators T_(φ)on the Hardy space over the bidisk.We first characterize the weighted composition operators,W_(u,v)which are J-symmetric and uni... In this paper,we investigate the complex symmetric structure of Toeplitz operators T_(φ)on the Hardy space over the bidisk.We first characterize the weighted composition operators,W_(u,v)which are J-symmetric and unitary.As a consequence,we characterize conjugations of the form A_(u,v).In addition,a class of conjugations of the form C_(λ,a)is introduced.We show that the class of conjugations C_(λ,a)coincides with the class of conjugations A_(u,v);we then characterize the complex symmetry of the Toeplitz operators T_(φ)with respect to the conjugation C_(λ,a). 展开更多
关键词 Toeplitz operators Hardy space complex symmetry
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THE MAIN INVARIANTS OF A COMPLEX FINSLER SPACE
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作者 Nicoleta ALDEA Gheorghe MUNTEANU 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期995-1011,共17页
In this paper we extend the results obtained in [3], where are investigated the general settings of the two-dimensional complex Finsler manifolds, with respect to a local complex Berwahl frame. The geometry of such ma... In this paper we extend the results obtained in [3], where are investigated the general settings of the two-dimensional complex Finsler manifolds, with respect to a local complex Berwahl frame. The geometry of such manifolds is controlled by three real invari- ants which live on T'M: two horizontal curvature invariants K and W and one vertical curvature invariant I. By means of these invariants are defined both the horizontal and the vertical holomorphic sectional curvatures. The complex Landsberg and Berwald spaces are of particular into, rest. Complex Berwald spaces coincide with K/ihler spaces, in the two - dimensional case, We establish the necessary and sufficient condition under which K is a constant and we obtain a characterization for the Kghler purely Hermitian spaces by the fact K = W=constant and I = 0. For the class of complex Berwald spaces we have K =W = 0. Finally, a classitication of two-dimensional complex Finsler spaces for which the horizontal curvature satisfies a special property is obtained. 展开更多
关键词 Berwald frame complex Landsberg space complex Berwald space holomorphic sectional curvature
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Survivability Mechanisms of Complex Computer Systems Based on Common Information Space
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作者 DODONOV Oleksandr JIANG Bo DODONOV Vadym 《计算机工程》 CAS CSCD 北大核心 2019年第7期41-45,共5页
The survivability of computer systems should be guaranteed in order to improve its operation efficiency,especially for the efficiency of its critical functions.This paper proposes a decentralized mechanism based on So... The survivability of computer systems should be guaranteed in order to improve its operation efficiency,especially for the efficiency of its critical functions.This paper proposes a decentralized mechanism based on Software-Defined Architecture(SDA).The concepts of critical functions and critical states are defined,and then,the critical functional parameters of the target system are collected and analyzed.Experiments based on the analysis results are performed for reconfiguring the implementations of the whole system.A formal model is presented for analyzing and improving the survivability of the system,and the problem investigated in this paper is reduced to an optimization problem for increasing the system survival time. 展开更多
关键词 SURVIVABILITY evaluation COMMON information space Software-Defined Architecture(SDA) complex COMPUTER systems
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A New Generalized Complex Orthogonal Space-Time Block Codes
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 CAS 2005年第3期241-243,共3页
Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and... Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and/or receiving antennas to create independent fading channels without penalty in bandwidth efficiency. Space-time block coding is an encoding scheme for communication over Rayleigh fading channels using multiple transmitting antennas. Space-time block codes from complex orthogonal designs exist only for two transmitting antennas. This paper generalizes a new complex orthogonal space-time block code for four transmitting antennas, whose decoding complexity is very low. Simulations show that the generalized complex orthogonal space-time block code has low bit error rate, full rate and possibly large diversity. 展开更多
关键词 space diversity space-time block code multiple antennas generalized complex orthogonal designs.
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A Characterization of Complex Projective Spaces by Sections of Line Bundles
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作者 Shuyu Liang Yanan Gao Yicai Zhao 《Advances in Pure Mathematics》 2015年第8期450-453,共4页
Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projecti... Let M be a n-dimensional compact irreducible complex space with a line bundle L. It is shown that if M is completely intersected with respect to L and dimH0(M, L) = n + 1, then M is biholomorphic to a complex projective space Pn of dimension n. 展开更多
关键词 complex space PROJECTIVE space LINE BUNDLE COMPLETE Intersected
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Points of Coincidence and Common Fixed Points for Ⅱ-Expansive Mappings on Complex Valued Metric Spaces
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作者 Yongjie Piao 《Analysis in Theory and Applications》 CSCD 2017年第4期366-374,共9页
Abstract. We use the two mappings satisfying II-expansive conditions on complex valued metric spaces to construct the convergent sequences and prove that the unique limit of the sequences is the point of coincidence o... Abstract. We use the two mappings satisfying II-expansive conditions on complex valued metric spaces to construct the convergent sequences and prove that the unique limit of the sequences is the point of coincidence or common fixed point of the two mappings. Also, we discuss the uniqueness of points of coincidence or common fixed points and give the existence theorems of unique fixed points. The obtained results generalize and improve the corresponding conclusions in references. 展开更多
关键词 complex valued metric space II-expansive mapping Cauchy sequence point ofcoincidence common fixed point.
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