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Curved Space-Time at the Planck Scale
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期167-179,共13页
This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the me... This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the metric tensor, is considered to be made up of a dynamic lattice of extremely small, localized fields that form a perfectly elastic Lorentz symmetric space-time at the global (macroscopic) scale. This theoretical model of space-time at the Planck scale leads to a somewhat surprising result in which matter waves in curved space-time radiate thermal gravitational energy, as well as an equally intriguing relationship for the anomalous dispersion of light in a gravitational field. 展开更多
关键词 Schwarzschild space-time Continuum Mechanics Planck Lattice Gravitational Radiation
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Coulomb Force, Charge, and Electric Properties under Collision Space-Time
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2023年第3期686-704,共19页
We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated... We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated how to make it compatible with electric properties such as charge and the Coulomb force. The aim of this paper is to show how electric properties can be reformulated to make it consistent with collision space-time. It is shown that we need to incorporate the Planck scale into the electric constants to do so. This is also fully possible from a practical point of view, as it has recently been shown how to measure the Planck length independent of other constants and without the need for dimensional analysis. 展开更多
关键词 Coulomb’s Law Elementary Charge Planck Charge Electric Units Collision space-time
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ON MARKOV CHAINS IN SPACE-TIME RANDOM ENVIRONMENTS 被引量:7
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作者 胡迪鹤 胡晓予 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期1-10,共10页
In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTR... In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTRE(+) by an initial distribution Φ and a random Markov kernel (RMK) p(γ). In Section 3, the authors es-tablish several equivalence theorems on MCSTRE and MCSTRE(+). Finally, the authors give two very important examples of MCMSTRE, the random walk in spce-time random environment and the Markov br... 展开更多
关键词 Random Markov kernel Markov chain in space-time random environemnt random walk in space-time random environment Markov branching chain in space-time random environment
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Performance Comparison of Space-Time Trellis Codes and Space-Time Transmit Diversity under the Same Bandwidth Efficiency
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作者 邬钢 陈明 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期10-13,共4页
Space time coding can provide high data rate and performance gain for wireless communication system. Performance comparison of space time trellis codes and space time transmit diversity is carried out under the sam... Space time coding can provide high data rate and performance gain for wireless communication system. Performance comparison of space time trellis codes and space time transmit diversity is carried out under the same bandwidth efficiency in this paper. We also propose some optimum low rate space time trellis codes in quasi static Rayleigh fading chan ̄nel. Performance analysis and simulation show that the low rate space time trellis codes outperform space time transmit diversity at the same bandwidth efficiency, and are more suitable for the power limited wireless communication system which has no strict requirement on bandwidth efficiency. 展开更多
关键词 space time trellis codes space time transmit diversity bandwidth efficiency
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E-Infinity Dualities, Discontinuous Spacetimes, Xonic Quantum Physics and the Decisive Experiment 被引量:2
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作者 Jean-Paul Auffray 《Journal of Modern Physics》 2014年第15期1427-1436,共10页
Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Nas... Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Naschie, this paper explores the deep implications of some of the dualities Dr El Naschie has identified and analyzed in his exposes, connecting them with our own Xonic Quantum Physics (XQP) which places dynamical action rather than spacetime and energy at the core of the System of the World. 展开更多
关键词 E-INFINITY El Naschie space time spacetime Topology CANTOR Sets Energy Xon Xonic Quantum Physics PLANCK Scale Dirac Electron
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Joint DOA and time delay estimation method for space-time coherent distributed signals based on search 被引量:1
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作者 Qian Bin Yang Wanlin Wan Qun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期341-346,共6页
Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on m... Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on multipath distribution function is given after new space and time manifold is reconstructed. Then joint spacetime signal subspace is obtained by converting acquired channel from time domain to frequency domain .Then space and time spectrum is formulated by the space sub-matrix and time sub-matrix taken out of joint space-time signal subspace, and parameters are estimated by searching the minimum eigenvalues of the space matrix and the time matrix. Lastly, A space and time parameters matching process is performed by using the orthogonal property between joint noise subspace and the space-time manifold. In contrast with tradition MUSIC, the algorithm we present here only need two 1- dimension searching and was not sensitive to different distribution function. 展开更多
关键词 space-time coherent distribution DOA Relative time delay Minimum eigenvalue.
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Protective Measures for Space Environment of Time-honored Brands——With Xi'an City as a Study Case
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作者 谷秋琳 《Journal of Landscape Research》 2010年第7期15-17,22,共4页
Based on the field survey and analysis of representative traditional time-honored shops in Xi'an City,specific measures for protecting their space environment were put forward,and the sustainable preservation and ... Based on the field survey and analysis of representative traditional time-honored shops in Xi'an City,specific measures for protecting their space environment were put forward,and the sustainable preservation and development pattern of such intangible cultural heritages in the future urban development was established. 展开更多
关键词 time-honored brands INTANGIBLE CULTURAL heritages space environment Protective measures
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The Quaternion Structure of Space-Time and Arrow of Time
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作者 Ying-Qiu Gu 《Journal of Modern Physics》 2012年第7期570-580,共11页
In fundamental theories of physics, the dynamical equations all have time inversion invariance. Except for the evolution of some simple system which has realistic inverse processes, but for a slightly more complicated... In fundamental theories of physics, the dynamical equations all have time inversion invariance. Except for the evolution of some simple system which has realistic inverse processes, but for a slightly more complicated system, the evolution processes are irreversible. This is the problem of arrow of time, which is always warmly debated. In different point of view, we find there may have some conceptual misunderstanding in the controversy: 1) The realization of an inverse process does not mean the time of the system goes backward. 2) The principles of relativity and covariance are the constraints to physical laws, but not constraints to specific solutions. The equations must be covariant, but the solutions are not definitely symmetric. 3) Time is a global property of the universe, which is a measurement of the evolution process of the universe. The internal time of a matter system reflecting its internal evolution speed also takes this cosmic time as a unified background and standard of measurement. 4) The universe has a unified cosmic time T and a cosmic space related to this cosmic time. They are objective and absolute. 5) The eigensolution of a spinor is a critical state losing time concept, which responses the interaction of environment with some uncertainty, then the evolution process of the world is not uniquely determined. 6) The non-uniqueness of the evolution process means that the inverse process is absent. So for a world including spinors, the evolution is essentially irreversible. In this paper, according to the widely accepted principles and direct calculations of transformation, we reveal the misunderstandings in the usual controversy, and then give more natural and reasonable explanations for structure of space-time and arrow of time. 展开更多
关键词 ARROW of time Invariance The Principle of RELATIVITY QUATERNION STRUCTURE of space-time SIMULTANEITY
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Reality of Space and Time
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作者 Tower Chen Zeon Chen 《Journal of Applied Mathematics and Physics》 2017年第4期774-784,共11页
In Newton’s classical physics, space and time are treated as absolute, independent quantities and can be discussed separately. In Special Relativity, Einstein proved that space and time are relative and dependent and... In Newton’s classical physics, space and time are treated as absolute, independent quantities and can be discussed separately. In Special Relativity, Einstein proved that space and time are relative and dependent and therefore must not be treated separately. Minkowski adopted four-dimensional space-time frames (4-d s-t frames), which indirectly revealed the dependency of space and time with the addition of a constraint for an event interval. We are not able to visualize 4-d s-t frames. Since space and time are inseparable, three-dimensional space-time frames (3-d s-t frames) can be constructed by embedding time into space to directly show the interdependency of space and time. Time contraction and length contraction can also be depicted graphically using 3-d s-t frames. We have much better understanding reality of space and time in 3-d s-t frames. This will lead to Contextual Reality for better understanding the universe. 展开更多
关键词 Special Relativity Four-Dimensional space-time FRAMES 4-D S-T FRAMES Three-Dimensional space-time FRAMES 3-D S-T FRAMES time CONTRACTION Length CONTRACTION CONTEXTUAL Attributes CONTEXTUAL REALITY
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Quasi-real time inversion method of three-dimensional epicenter coordinate, trigger time, and magnitude based on CORS 被引量:1
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作者 Xiao Dongsheng Chang Ming +2 位作者 Su Yong Hu Qijun Yu Bing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2016年第3期425-433,共9页
This study explores the quasi-real time inversion principle and precision estimation of three-dimensional coordinates of the epicenter, trigger time and magnitude of earthquakes with the aim to improve traditional met... This study explores the quasi-real time inversion principle and precision estimation of three-dimensional coordinates of the epicenter, trigger time and magnitude of earthquakes with the aim to improve traditional methods, which are flawed due to missing information or distortion in the seismograph records. The epicenter, trigger time and magnitude from the Lushan earthquake are inverted and analyzed based on high-frequency GNSS data. The inversion results achieved a high precision, which are consistent with the data published by the China Earthquake Administration. Moreover, it has been proven that the inversion method has good theoretical value and excellent application prospects. 展开更多
关键词 continuous operation reference station (CORS) trigger time three dimensional coordinate magnitude inversion
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Space station short-term mission planning using ontology modelling and time iteration 被引量:5
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作者 Huijiao Bu Jin Zhang Yazhong Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期407-421,共15页
This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time ... This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time of the astronauts properly. A domain model is developed by using the ontology theory to describe the concepts, constraints and relations of the planning domain formally, abstractly and normatively. A method based on time iteration is adopted to solve the short-term planning problem. Meanwhile, the resolving strategies are proposed to resolve different kinds of conflicts induced by the constraints of power, heat, resource, astronaut and relationship. The proposed approach is evaluated in a test case with fifteen missions, thirteen resources and three astronauts. The results show that the developed domain ontology model is reasonable, and the time iteration method using the proposed resolving strategies can successfully obtain the plan satisfying all considered constraints. 展开更多
关键词 space station mission planning ontology modelling time iteration
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Nature of Black Holes and Space-Time around Them
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作者 Amir Ali Tavajoh 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第1期96-105,共10页
Based on the Mach’s principle, black holes warp the space time in a way that geodesic for every object which is moving toward black hole starts to bend and object starts to rotate around the black hole. Even light ca... Based on the Mach’s principle, black holes warp the space time in a way that geodesic for every object which is moving toward black hole starts to bend and object starts to rotate around the black hole. Even light cannot be able to escape from the strong gravitational field of black hole and all the light like paths will warp so as to fall farther to the hole. Before arriving to the Schwarzschild’s Sphere, object faces with length extension because of the difference between amount of tidal forces on the nearest and furthest points of object that take the object apart and after passing the Schwarzschild’s sphere, based on the Special relativity of Einstein, the parts of object face with length contraction. In comparison between strange stars and black holes we conclude that core of strange stars has a temperature and pressure not sufficient for up and down quarks and they turn into strange ones. However, in core of black holes, because of massive stars and hot gases falling into it, they are always in a high temperature and pressure. So they can be made up of up and down quarks. At the Ergo sphere Region of black hole, a particle that gets into it will divide into 2 pieces, one of them falls into the black hole and another gets out of the Schwarzschild sphere very fast and it’s called the black hole radiation. According to the Diagram drawn by R. Rafini and J. Weeler, an object gets out of white hole in past space-time, it can be able to send signals to us and we can receive it but black hole which is located in future space-time, after object enters to the Schwarzschild’s Sphere, the signals it sends won’t be received. In order to reach the third space-time which is like a mirror to our universe, our speed needs to exceed the speed of light to pass the Einstein-Rosen Bridge. As a conclusion, structure of black holes can be made up of up and down quarks and everything falls into the black hole, collapses and turns into a bunch of quarks. Space-time around black holes, based on Rafini-Weeler diagram, is like a frontier between our space-time and other space-times. So it can be possible to reach past space-time and other space-times. 展开更多
关键词 General RELATIVITY GEODESIC Rafini-Weeler Diagram STRANGE Stars Einstein-Rosen Bridge Schwarzschild’s SPHERE Ergo SPHERE space-time Curvature time Warp Special RELATIVITY Mach’s Principle
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ICON/MIGHTI与TIMED/SABER探测温度数据的对比
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作者 牟宵 闫召爱 +4 位作者 程旋 陈志芳 杨钧烽 胡雄 潘蔚琳 《空间科学学报》 CAS CSCD 北大核心 2024年第5期794-805,共12页
ICON卫星为临近空间环境特性研究、建模和预报提供了新数据.通过对ICON/MIGHTI与TIMED/SABER在90~105 km高度探测温度数据的比较,计算两者的年平均温度偏差和均方根误差,同时分析月平均温度偏差在不同月份中随高度和纬度的分布情况,为MI... ICON卫星为临近空间环境特性研究、建模和预报提供了新数据.通过对ICON/MIGHTI与TIMED/SABER在90~105 km高度探测温度数据的比较,计算两者的年平均温度偏差和均方根误差,同时分析月平均温度偏差在不同月份中随高度和纬度的分布情况,为MIGHTI和SABER温度探测数据在临近空间大气建模和预报应用提供参考依据.结果表明,MIGHTI和SABER的温度垂直廓线变化趋势基本吻合,数值上有所差异.在12°S-42°N范围内,MIGHTI探测温度与SABER相比,在90~93 km时偏低,偏差最大值约2.5 K,在93~105 km偏高,偏差的绝对值最大约10 K.在不同季节,白天的温度偏差通常高于夜晚.SABER和MIGHTI的月平均温度偏差随季节和纬度的变化显著,夏季时的月平均温度偏差最大,且温度的均方根误差最大. 展开更多
关键词 大气温度 临近空间 数据比较 ICON/MIGHTI timeD/SABER
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Performance Analysis for Orthogonal Time Frequency Space Modulation Systems with Generalized Waveform
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作者 Shuo Li Lixia Xiao +3 位作者 Yangyang Liu Guanghua Liu Pei Xiao Tao Jiang 《China Communications》 SCIE CSCD 2023年第4期57-72,共16页
Orthogonal time-frequency space(OTFS),which exhibits beneficial advantages in high-mobility scenarios,has been considered as a promising technology in future wireless communication systems.In this paper,a universal mo... Orthogonal time-frequency space(OTFS),which exhibits beneficial advantages in high-mobility scenarios,has been considered as a promising technology in future wireless communication systems.In this paper,a universal model for OTFS systems with generalized waveform has been developed.Furthermore,the average bit error probability(ABEP)upper bounds of the optimal maximum likelihood(ML)detector are first derived for OTFS systems with generalized waveforms.Specifically,for OTFS systems with the ideal waveform,we elicit the ABEP bound by recombining the transmitted signal and the received signal.For OTFS systems with practical waveforms,a universal ABEP upper bound expression is derived using moment-generating function(MGF),which is further extended to MIMO-OTFS systems.Numerical results validate that our theoretical ABEP upper bounds are concur with the simulation performance achieved by ML detectors. 展开更多
关键词 orthogonal time frequency space(OTFS) average bite error rate(ABEP) maximum likelihood(ML) moment generating-function(MGF)
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The Singularity of the Big Bang Can Be Described in Greater Depth than the Limits of the Planck Time and Length
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作者 Slobodan Spremo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期51-54,共4页
In this paper, we determine the frequency, energy and momentum of the primordial spherical wave at the birth of our universe, which are consistent with the fact that the total energy of our universe was created in the... In this paper, we determine the frequency, energy and momentum of the primordial spherical wave at the birth of our universe, which are consistent with the fact that the total energy of our universe was created in the hot Big Bang. With this, we also indirectly demonstrate the consistency of previous works on the hypothesis of primary particles, by using their results. We obtain a hyper-high initial frequency of the spherical wave, which is not in contradiction with string theory. 展开更多
关键词 Flat space and time Primary Particles Quantum of Speed Spherically Wave
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Design and Analysis of Spatial Modulation Based Orthogonal Time Frequency Space System 被引量:3
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作者 Yingchao Yang Zhiquan Bai +4 位作者 Ke Pang Piming Ma Haixia Zhang Xinghai Yang Dongfeng Yuan 《China Communications》 SCIE CSCD 2021年第8期209-223,共15页
In this paper,we design a spatial modulation based orthogonal time frequency space(SMOTFS)system to achieve improved transmission reliability and meet the high transmission rate and highspeed demands of future mobile ... In this paper,we design a spatial modulation based orthogonal time frequency space(SMOTFS)system to achieve improved transmission reliability and meet the high transmission rate and highspeed demands of future mobile communications,which fully utilizes the characteristics of spatial modulation(SM)and orthogonal time frequency space(OTFS)transmission.The detailed system design and signal processing of the SM-OTFS system have been presented.The closed-form expressions of the average symbol error rate(ASER)and average bit error rate(ABER)of the SM-OTFS system have been derived over the delay-Doppler channel with the help of the union bounding technique and moment-generating function(MGF).Meanwhile,the system complexity has been evaluated.Numerical results verify the correctness of the theoretical ASER and ABER analysis of the SM-OTFS system in the high signal-to-noise ratio(SNR)regions and also show that the SM-OTFS system outperforms the traditional SM based orthogonal frequency division multiplexing(SM-OFDM)system with limited complexity increase under mobile conditions,especially in high mobility scenarios. 展开更多
关键词 orthogonal time frequency space(OTFS) spatial modulation based OTFS(SM-OTFS) delay-Doppler domain average symbol error rate(ASER) average bit error rate(ABER)
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Euclidean Model of Space and Time 被引量:1
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作者 Radovan Machotka 《Journal of Modern Physics》 2018年第6期1215-1249,共35页
The aim of this work is to show that the currently widely accepted geometrical model of space and time based on the works of Einstein and Minkowski is not unique. The work presents an alternative geometrical model of ... The aim of this work is to show that the currently widely accepted geometrical model of space and time based on the works of Einstein and Minkowski is not unique. The work presents an alternative geometrical model of space and time, a model which, unlike the current one, is based solely on Euclidean geometry. In the new model, the pseudo-Euclidean spacetime is replaced with a specific subset of four-dimensional Euclidean space. The work shows that four-dimensional Euclidean space allows explanation of known relativistic effects that are now explained in pseudo-Euclidean spacetime by Einstein’s Special Theory of Relativity (STR). It also shows simple geometric-kinematical nature of known relativistic phenomena and among others explains why we cannot travel backward in time. The new solution is named the Euclidean Model of Space and Time (EMST). 展开更多
关键词 SPECIAL Theory of RELATIVITY Euclidean space Four-Dimensional space time DILATION LENGTH CONTRACTION
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Joint multi-user space time block coding and beamforming via convolutional weighting 被引量:1
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作者 邢志强 Zhou Tingxian Meng Weixiao 《High Technology Letters》 EI CAS 2006年第2期119-123,共5页
A convolutional weighting (CW) scheme applied to a half-wavelength spacing array was proposed for multi-user system to joint STBC (space time block ceding) and beam forming (BF). The transmitting beam is equival... A convolutional weighting (CW) scheme applied to a half-wavelength spacing array was proposed for multi-user system to joint STBC (space time block ceding) and beam forming (BF). The transmitting beam is equivalent to the product of two sub-beams. One is used to realize interference suppression, while the other is employed to form a couple of uncorrelated channels from base station (BS) to the desited user (to meet the requirement of STBC) and to maximize SINR (signal-to-interference-plus noise ratio) at the desired receiver. As an optimum combination of STBC and beam forming, the proposed scheme can achieve both full diversity order of STBC and array gain of BF. Meanwhile, it can also effec- tively restrain multi-user interference by nulling. Simulation results show that the proposed scheme can significantly improve the BER (Bit Error Rate) performance and enhance system capacity as compared with the conventional eigen-beamforming (EBF) technique applied to a half-wavelength spacing array. 展开更多
关键词 space time block ceding beam forming convolutional weighting multi-user interference
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Determining the time and space domains forestimating b value in seismic zoning
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作者 黄玮琼 李文香 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第5期3-8,共6页
To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M... To take the seismic zone that includes the great shock with M S8.5 as the statistical unit of estimating b value can often lead to more large variance, because the seismogenic zone of the great shock with M S8.5 are larger than that delineated in general seismic zone. Two-level statistical units are considered in this paper. The seismic province is the first level unit that is suitable for group of earthquakes including the great shock of M S8.5. A seismic province can be divided into several seismic zones. They can be taken as the second level unit for group of quakes in which the super magnitude of the greatest shock do not exceed 8. Because of the nonstationarity in time of seismic activity, the unbalancedness of data and differential of seismic temporal series feature in different areas need to be considered when we select the time period for estimating b value. According to local conditions, the time period is selected at one′s discretion in order to reflect seismicity level of this statistical unit in future 100 years. 展开更多
关键词 estimating b VALUE statistical unit time period magnitude interval
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SPACE-TIME TEXTURE AND TECTONIC EVOLUTION OF QAMDO BLOCK IN EAST TIBET
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作者 Wang Mingjie, Wang Gaoming 《地学前缘》 EI CAS CSCD 2000年第S1期175-177,共3页
Qamdo block in the east Tibet lay in front of southwestern margin of the Yangtze landmass and was one of many micro\|blocks between the Gondwana and the Eurasia continents .It played an important role in the developme... Qamdo block in the east Tibet lay in front of southwestern margin of the Yangtze landmass and was one of many micro\|blocks between the Gondwana and the Eurasia continents .It played an important role in the development of the multi\|arc\|basin system of the north sector of the Jinsha\|lancang\|nujiang rivers . Space\|time texture of the block reflected the tectonic evolution of the east Tibet and neighbouring areas directly, providing important information for evolutionary history of the east Tethys.1\ Crustal structure of the Qamdo block\;Crustal structure of the Qamdo block is characterized by “double basement and double cover”.By double basement is meant the Middle—Upper Proterozoic crystalline basement and the Lower Paleozoic folded basement. The Middle—Upper Proterozoic crystalline basement is composed of medium\|high\|grade metamorphic biotite\|plagiogneiss, plagioclase\|amphibole schist, nacritid intercalated with (intermediate\|) basic metavolcanite. These rocks are characteristic of strong ductile deformed metamorphic core complex. The zircon of gneiss yields an U\|Pb age of 1680~2200Ma while the basic metavolcanite give a Sm\|Nd age of 1594Ma.The Lower Paleozoic folded basement consists of the Lower Ordovician and Silurian. Basement of the Qamdo block is similar to that of the Yangtze landmass. By double cover we mean two covers consisting of the Upper Paleozoic and Mesozoic, respectively. The Upper Paleozoic is composed of carbonate and clastic rock which were formed from epicontinental to back\|arc basins. The Mesozoic consists of the Upper Triassic—Cretaceous concordant formations which were formed in a back\|arc foreland basin.Sequences of the formations are molasse, neritic carbonate, paralic coal\|bearing rock and terrigenous red clastic rock from the bottom to the top. 展开更多
关键词 EAST TIBET Qamdo BLOCK time\|space TEXTURE structural evol ution
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