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The Time Being and Its Disidentification With the Modern Liberal Order
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作者 Lulwa Al Khalifa 《Journal of Literature and Art Studies》 2024年第11期949-954,共6页
The Time Being is a concept that is rooted in the here and now,cognizant of the importance of every action in a moment that can prevent harm and promote goodness.Such moments have the power to leave enduring impressio... The Time Being is a concept that is rooted in the here and now,cognizant of the importance of every action in a moment that can prevent harm and promote goodness.Such moments have the power to leave enduring impressions that transcend time and location.This idea of a time being is one that Ozeki uses to emphasize the historical ties and influence of her characters.It also assists readers in recognizing the similarities between historical oppressive systems and the ways in which they can endure.Kandice Chuh also addresses the notion of applying anti-Western philosophies to better understand oneself in order to disassociate and dismantle contemporary structures that have the potential to damage and skew the perception of our shared humanity.Through Buddhist philosophy,Dogen Zenji’s concept of a time being,and disidentification with demanding neoliberal structures,the novel’s characters are able to discover new perspectives on life and develop a new sense of self that enables them to want to live.Ozeki finds ways to give her characters a stronger sense of self by drawing on Buddhist teachings.Through Zenji’s teachings,Nao,her father,and great-uncle,find peace and consolation in worlds that are too focused on future comforts that can be destructive to the present self. 展开更多
关键词 time being buddhism HUMANISM
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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study
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作者 Jieying Wu Shan Ye +2 位作者 Xiangyi Liu Yingsheng Xu Dongsheng Fan 《Neural Regeneration Research》 SCIE CAS 2025年第5期1505-1512,共8页
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ... Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis. 展开更多
关键词 amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread
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Complex time-space spreading and focal mechanism of the 1989 Batang earthquake swarm (M_s=6.7) 被引量:1
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作者 程万正 陈天长 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第2期201-208,共8页
On the basis of field observations, the complex time-space spreading pattern and focal mechanism of the 1989Batang earthquake swarm are studied in this paper. The fault motions of the epicenter area are analysed bythe... On the basis of field observations, the complex time-space spreading pattern and focal mechanism of the 1989Batang earthquake swarm are studied in this paper. The fault motions of the epicenter area are analysed bythe leveling survey before and after strong events. From the given simplified focal mechanical model of theswarm,the process of fracture indicates that swarm strong ruptures are associated with the spreading and thevirgation of the barrier of irregularen en echelon source fault system. 展开更多
关键词 strong earthquake swarm time-space spreading source fault system focal mechanism
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A Connection between Geometrical Spreading and the Adjoint Field in Travel Time Tomography
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作者 William Menke 《Applied Mathematics》 2020年第2期84-96,共13页
The goal of tomography is to reconstruct a spatially-varying image function s(x,m), where x is position and m is a finite-length vector of parameters. Many reconstruction methods minimize the total L2 error E ≡ eTe, ... The goal of tomography is to reconstruct a spatially-varying image function s(x,m), where x is position and m is a finite-length vector of parameters. Many reconstruction methods minimize the total L2 error E ≡ eTe, where individual errors ei quantify misfit between predictions and observations, to quantify goodness of fit. So-called adjoint state methods allow the gradient &#8706;E/&#8706;mi to be computed extremely efficiently from an adjoint field, facilitating image reconstruction by gradient-descent methods. We examine the structure of the differential equation for the adjoint field under the ray approximation and find that it has the same form as the transport equation, whose solution involves the well-known geometrical spreading function R Consequently, as R is routinely tabulated as part of a ray calculation, no extra work is needed to compute the adjoint field, permitting a rapid calculation of the gradient?&#8706;E/&#8706;mi. 展开更多
关键词 ADJOINT State METHOD EIKONAL EQUATION GEOMETRICAL spreadING Gradient-Descent METHOD Transport EQUATION Travel time Tomography
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TIME DOMAIN PROCESSING MODE SPREAD SPECTRUM SYSTEM
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作者 何世平 《Journal of Electronics(China)》 1995年第3期276-283,共8页
The construction and specifications of a surface acoustic wave storage correlator are described. A time domain processing mode spread spectrum system is presented. An analysis of the interference rejection for this sy... The construction and specifications of a surface acoustic wave storage correlator are described. A time domain processing mode spread spectrum system is presented. An analysis of the interference rejection for this system is provided. The formula for calculating the probability of error of the system is given. The experimental results agree with the theoretical analysis. 展开更多
关键词 time DOMAIN processing spread SPECTRUM system STORAGE CORRELATOR
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A New En-/de-coding Scheme of Spreading Time OCDMA
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作者 余重秀 《High Technology Letters》 EI CAS 2000年第1期38-41,共4页
In this paper, we propose a new en /de coding scheme of spreading time OCDMA utilizing the dispersion of grating and filter in frequency domain. The key components of the scheme are grating pair, Fourier transformat... In this paper, we propose a new en /de coding scheme of spreading time OCDMA utilizing the dispersion of grating and filter in frequency domain. The key components of the scheme are grating pair, Fourier transformation lens, phase filter etc. The results of design and calculation are shown that the spreading time of input pulse can be up to nanosecond duration and the phase filter can provide pseudo noise bursts in time domain. The requirements for Laser and optical detection equipment in the scheme are reduced. So the new scheme proposed by us is effective for OCDMA en /de coding of coherent ultra short pulses. 展开更多
关键词 OCDMA En /de CODING spreadING time phase modulation
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AQAM under high time delay spread conditions
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作者 单晓红 朱秀珊 +1 位作者 郭银景 刘治文 《Journal of Measurement Science and Instrumentation》 CAS 2012年第2期152-156,共5页
An analysis process is described for adaptive quadrature amplitude modulation(AQAM)of constant-power constant-symbol-rate over frequency-selective Rayleigh fading channels with inter symbol interference(ISI)and Gaussi... An analysis process is described for adaptive quadrature amplitude modulation(AQAM)of constant-power constant-symbol-rate over frequency-selective Rayleigh fading channels with inter symbol interference(ISI)and Gaussian noise.The delay spread resistance of the AQAM scheme is put forward by studying its average throughput and average bit-error-rate(BER),both of which can be expressed as functions of two variables,the ratio of root mean square(RMS)delay spread to symbol period and the ratio of average symbol energy to noise.Average throughput reacts regularly to the latter,whereas it does not react to the former.The AQAM scheme is highly superior in the delay spread resistance in comparison with the fixed modulation modes.Gains of the AQAM scheme over the fixed modes become more significant as the delay spread becomes severer or the average throughput decreases. 展开更多
关键词 time delay spread adaptive modulation adaptive quadrature amplitude modulation(AQAM)
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Empress Wu Zetian and the Development of Buddhism:Historical Significance and Contemporary Implications
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作者 SHI Yuxin 《Cultural and Religious Studies》 2023年第11期564-568,共5页
The paper focuses on Wu Zetian,the only empress in China’s history,and her relationship with Buddhism.This study focuses on the book Zizhi Tongjian and compares the differences in the portrayal of Wu Zetian’s connec... The paper focuses on Wu Zetian,the only empress in China’s history,and her relationship with Buddhism.This study focuses on the book Zizhi Tongjian and compares the differences in the portrayal of Wu Zetian’s connection with Buddhism with the ancient texts of the Old Tang Book and the New Tang Book.It uses historical contextualism to analyze the epochal implications of these differences in the Northern Song Dynasty.Additionally,the paper discusses how historians downplayed or marginalized Wu Zetian’s achievements while emphasizing the negative aspects of her reign.Notably,historian Sima Guang,who was influenced by Confucianism and his own political situation,produced a biased description of Wu Zetian and the Buddhism which she promoted during her reign. 展开更多
关键词 Wu Zetian Zizhi Tongjian buddhism character image implication of time
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Efficient spread space-time block coding scheme in multiple antenna systems
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作者 Qiu Ling Zheng Xiayu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期258-262,共5页
Space-time coding is an important technique that can improve transmission performance at fading environments in mobile communication systems. In this paper, we propose a novel diversity scheme using spread spacetime b... Space-time coding is an important technique that can improve transmission performance at fading environments in mobile communication systems. In this paper, we propose a novel diversity scheme using spread spacetime block coding (SSTBC) in multiple antenna systems. At the transmitter, the primitive data are serial to parallel converted to multiple data streams, and each stream is rotated in constellation. Then Walsh codes are used to spread each symbol to all antenna space in a space-time block. The signals received from all receiver antennas are combined with the maximum ratio combining (MRC), equalized with linear equalizer to eliminate the inter-code interference and finally demodulated to recover to transmit data by using the one-symbol maximum likelihood detector. The proposed scheme does not sacrifice the spectrum efficiency meanwhile maintains the transceiver with low complexity. Owing to the transmission symbols of different transmit antennas passing through all the spatial subchannels between transceiver antenna pairs, the system obtains the partial additional space diversity gain of all spatial paths. It is also shown that the diversity gain is better than the previous space-time block coding (STBC) schemes with full transmission rate. 展开更多
关键词 multiple antennas spread space-time block coding (SSTBC) DIVERSITY full transmission rate.
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A method to measure transit time spread of photomultiplier tubes with Cherenkov light
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作者 WU Chong DONG Huasong SUN Zhijia 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第6期344-348,共5页
With the technology of coincidence method, transit time spreads (TTSs) of PMTs are measured with Cherenkov light on the photocathode window of photomultiplier tube (PMT) produced by cascade γ radiation source, 60Co. ... With the technology of coincidence method, transit time spreads (TTSs) of PMTs are measured with Cherenkov light on the photocathode window of photomultiplier tube (PMT) produced by cascade γ radiation source, 60Co. TTSs with single and multi-photoelectron which are analyzed by convolution of Poisson and Gaussian are obtained. The study to XP2020 and XP2020Q PMTs shows that TTSs are consistent with data supplied by Philips. TTSs are inversely proportional to the square roots of number of photoelectrons. The method is feasible when single and multi-photoelectron can be distinguished. 展开更多
关键词 光电倍增管 通过时间 并联机床 机床技术 钴-60 辐射源 PMT 卷积和
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喷雾助剂对乙基多杀菌素药液在杧果叶片润湿铺展行为的影响
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作者 潘波 王冰洁 +2 位作者 杜长远 林勇 姜蕾 《热带作物学报》 北大核心 2025年第1期180-188,共9页
乙基多杀菌素是防治杧果蓟马的常用药剂之一,农药喷雾助剂的添加可以提高农药的药效。合理选择和使用助剂产品,对提高农药利用率、减少农药使用量至关重要。本研究通过测定添加5种不同类型、不同浓度的农药助剂产品后乙基多杀菌素药液... 乙基多杀菌素是防治杧果蓟马的常用药剂之一,农药喷雾助剂的添加可以提高农药的药效。合理选择和使用助剂产品,对提高农药利用率、减少农药使用量至关重要。本研究通过测定添加5种不同类型、不同浓度的农药助剂产品后乙基多杀菌素药液的静态、动态表面张力,以及药液在杧果叶片正面、背面的接触角、铺展面积和蒸发时间,探究不同类型农药助剂产品在杧果叶片表面的润湿铺展行为。结果表明:添加不同助剂产品均能有效降低乙基多杀菌素药液的静态、动态表面张力,同时降低药液在叶片表面的接触角,提高药液在杧果叶片表面的铺展面积。除高分子类助剂(诺普信天盾)在叶片背面表现出抗蒸发性外,其他助剂产品均缩短了蒸发时间。不同类型的助剂产品在杧果叶片上的润湿性表现并不一致,有机硅类助剂(极润)润湿性最好,其余依次为硅酸金属复合盐类助剂(迈道)、改性植物油(迈飞)、橙皮精油(丹罗丰)、高分子类助剂(诺普信天盾)。通过比较不同处理组药液在杧果叶片正面、背面的润湿铺展行为,得出叶片背面比正面更难以被农药药液润湿。药液的理化性质和叶片的表面结构是影响喷雾液滴在叶片上润湿行为的重要因素。杧果蓟马常常在叶片背面活动取食,因此在防治杧果蓟马时,应根据助剂的类型、蓟马的为害特点选择合适的浓度,才能取得较好的防治效果。研究结果揭示了不同类型助剂在杧果叶片上的润湿铺展行为,为合理选择使用农药喷雾助剂产品提供数据支撑。 展开更多
关键词 喷雾助剂 表面张力 接触角 润湿面积 干燥时间 杧果
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Analysis for MIMO correlated frequency-selective channel in the presence of interference 被引量:3
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作者 Xiao Hailin Nie Zaiping +1 位作者 Li Xin Ouyang Shan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期679-682,共4页
The space time spreading, superimposed training sequences, and space-time coding are used to present a multiple input and multiple output (MIMO) systems model, and a closed-form of average error probability upper bo... The space time spreading, superimposed training sequences, and space-time coding are used to present a multiple input and multiple output (MIMO) systems model, and a closed-form of average error probability upper bound expression for MIMO correlated frequency-selective channel in the presence of interference (co-channel interference and jamming signals) is derived. Moreover, the correlation at both ends of the wireless link that can be incorporated equivalently into correlation at the transmit end is also derived, which is significant to analyze space-time link algorithm of MIMO systems. 展开更多
关键词 average error probability upper bound Chernoff bound space time spreading space time coding
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Quantification of the impact of TOF and PSF on PET images using the noise-matching concept: clinical and phantom study 被引量:1
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作者 M. Shekari P. Ghafarian +1 位作者 S. Ahangari M. R. Ay 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第11期258-265,共8页
This study was to assess quantitatively the accuracy of ^(18)F-FDG PET/CT images reconstructed by TOF+PSF and TOF only, considering the noise-matching concept to minimize probable bias in evaluating algorithm performa... This study was to assess quantitatively the accuracy of ^(18)F-FDG PET/CT images reconstructed by TOF+PSF and TOF only, considering the noise-matching concept to minimize probable bias in evaluating algorithm performance caused by noise. PET images of similar noise level were considered. Measurements were made on an inhouse phantom with hot inserts of Φ10–37 mm, and oncological images of 14 patients were analyzed. The PET images were reconstructed using the OSEM, OSEM+TOF and OSEM+TOF+PSF algorithms. Optimal reconstruction parameters including iteration, subset, and FWHM of post-smoothing filter were chosen for both the phantom and patient data. In terms of quantitative accuracy, the recovery coefficient(RC) was calculated for the phantom PET images. The signal-to-noise ratio(SNR),lesion-to-background ratio(LBR), and SUV_(max)were evaluated from the phantom and clinical data. The smallest hot insert(Ф10 mm) with 2:1 activity concentration ratio could be detected in the PET image reconstructed using the TOF and TOF+PSF algorithms, but not the OSEM algorithm. The relative difference for SNR between the TOF+PSF and OSEM showed significantly higher values for smaller sizes, while SNR change was smaller for Ф22–37 mm inserts both 2:1 and 4:1 activity concentration ratio. In the clinical study, SNR gains were 1.6 ± 0.53 and 2.7 ± 0.74 for the TOF and TOF+PSF, while the relative difference of contrast was 17 ± 1.05 and 41.5 ± 1.85% for the TOF only and TOF+PSF, respectively. The impact of TOF+PSF is more significant than that of TOF reconstruction, in smaller inserts with low activity concentration ratio. In the clinical PET/CT images, the use of the TOF+PSF algorithm resulted in better SNR and contrast for lesions, and the highest SUV_(max)was also seen for images reconstructed with the TOF+PSF algorithm. 展开更多
关键词 time of FLIGHT (TOF) Point spread function(PSF) LESION DETECTABILITY PET Quantification Image reconstruction SUV
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The Analysis of an SIRS Epidemic Model with Discrete Delay on Scale-Free Network 被引量:1
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作者 Tao Li Qiming Liu Baochen Li 《Applied Mathematics》 2015年第11期1939-1946,共8页
A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive numb... A new epidemic SIRS model with discrete delay on scale-free network is presented. We give the formula of the basic reproductive number for the model and prove that the disease dies out when the basic reproductive number is less than unity, while the disease is uniformly persistent when the basic reproductive number is more than unity. Numerical simulations are given to demonstrate the main results. 展开更多
关键词 SCALE-FREE Network EPIDEMIC spreadING ATTRACTIVITY UNIFORMLY PERSISTENCE time Delay
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Spreading behavior of SIS epidemic model on networks with dynamical topology
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作者 夏承遗 刘忠信 +1 位作者 陈增强 袁著祉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第6期766-770,共5页
Based on the two-dimensional regular lattice,a modified SIS(Susceptible-Infected-Susceptible)epidemic model with motion rules is presented to study the spreading behavior on networks with dynamical topology.The mean-f... Based on the two-dimensional regular lattice,a modified SIS(Susceptible-Infected-Susceptible)epidemic model with motion rules is presented to study the spreading behavior on networks with dynamical topology.The mean-field theory is utilized to analyze the critical threshold(λc)of epidemic spreading under the randomly mixing conditions.It is found that λc is only related with the population density within the lattice.Large-scale numerical simulations are carried out to verify the mean-field results,and it is observed that the long-range probability p largely affects the epidemic spreading behavior.In addition,the effect of the dual time scales on epidemic spreading is also investigated by the simulations,and it is shown that the dual time scales accelerate the dynamic spreading behavior.The results indicate that the model with motion can help us to further understand the real epidemics. 展开更多
关键词 complex networks epidemic spreading dynamical topology dual time scales
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Spreading Speed for a Periodic Reaction-diffusion Model with Nonmonotone Birth Function
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作者 HUANG Ye-hui WENG Pei-xuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期467-474,共8页
A reaction-diffusion model for a single species with age structure and nonlocal reaction for periodic time t is derived. Some results about the model with monotone birth function are firstly introduced, and then by co... A reaction-diffusion model for a single species with age structure and nonlocal reaction for periodic time t is derived. Some results about the model with monotone birth function are firstly introduced, and then by constructing two auxiliary equations and squeezing method, the spreading speed for the system with nonmonotone birth function is obtained. 展开更多
关键词 spreading speed nonmonotone birth function period time age structure nonlocal reaction
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BIFURCATION CONTROL FOR A FRACTIONAL-ORDER DELAYED SEIR RUMOR SPREADING MODEL WITH INCOMMENSURATE ORDERS
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作者 叶茂林 蒋海军 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2662-2682,共21页
A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation i... A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation is investigated by considering time delay as bifurcation parameter for the system without a feedback controller.Then,a state feedback controller is designed to control the occurrence of bifurcation in advance or to delay it by changing the parameters of the controller.Finally,in order to verify the theoretical results,some numerical simulations are given. 展开更多
关键词 rumor spreading FRACTIONAL-ORDER time delay bifurcation control
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Space-time Channel Modeling and Simulations for 2GHz Wireless Communications 被引量:2
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作者 Ning Ma 《通讯和计算机(中英文版)》 2006年第3期72-76,共5页
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Performance of Block Space-Time Code in Wireless Channel Dynamics
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作者 Won Mee JANG Jong Hak JUNG 《International Journal of Communications, Network and System Sciences》 2009年第6期461-468,共8页
In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides af... In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides affordable complexity in design and construction. Our results show that the performance of the block space-time code may not be as good as conventionally convolutional coding with serial transmission for some channel features. As channel approaches fast fading, a coded single antenna scheme can collect as much diversity as desired by correctly choosing the free distance of code. The results also point to the need for robust space-time code in dynamic wireless fading channels. We expect that self-encoded spread spec-trum with block space-time code will provide a robust performance in dynamic wireless fading channels. 展开更多
关键词 SPACE-time CODES DIVERSITY Multiple Transmit ANTENNAS Self-Encoded spread SPECTRUM
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时间反转直扩通信系统及性能分析
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作者 雷维嘉 邹梦婷 +1 位作者 雷宏江 唐宏 《电子学报》 EI CAS CSCD 北大核心 2024年第1期69-80,共12页
时间反转传输技术的空时聚焦特性能够有效地提升通信系统的性能.本文设计了一种将时间反转技术应用于直扩通信系统的方案,并对多径衰落信道下单用户和多用户系统的接收信干噪比、系统容量、误比特率等性能进行了理论分析与仿真验证.理... 时间反转传输技术的空时聚焦特性能够有效地提升通信系统的性能.本文设计了一种将时间反转技术应用于直扩通信系统的方案,并对多径衰落信道下单用户和多用户系统的接收信干噪比、系统容量、误比特率等性能进行了理论分析与仿真验证.理论与仿真结果表明,通过时间反转预处理,直扩通信系统的性能得到了改善,且优于复杂度较高的多通道Rake接收的系统,且多径数目越多,优势越明显. 展开更多
关键词 直接序列扩频 时间反转 RAKE接收机 系统容量 误比特率
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