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反馈联合检测算法性能上限研究

信号处理 2007年第1期23卷 124-126页

作者：秦洪峰中兴通讯股份有限公司西安710065

反馈联合检测算法通常可为迫零数据块判决反馈均衡器(ZF-BDFE)和最小均方差数据块判决反馈均衡器(MMSE-BDFE)算法。本文研究了反馈联合检测算法性能及其上限,提出了算法性能上限的分析结构。研究表明,MMSE- BDFE算法性能优于ZF-BDFE；ZF... 详细信息

反馈联合检测算法通常可为迫零数据块判决反馈均衡器(ZF-BDFE)和最小均方差数据块判决反馈均衡器(MMSE-BDFE)算法。本文研究了反馈联合检测算法性能及其上限,提出了算法性能上限的分析结构。研究表明,MMSE- BDFE算法性能优于ZF-BDFE；ZF-BDFE和MMSE-BDFE分别与各自算法性能上限之间相差均不会超过0．5dB。反馈联合检测算法可以满足实际通信系统的要求,应用前景良好。

关键词：反馈联合检测性能上限 ZF-BDFE MMSE-BDFE

Measurement-Based Channel Characterization for 5G Wireless Communications on Campus Scenario

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ZTE Communications 2017年第1期15卷 8-13页

作者： YANG Mi HE Ruisi AI Bo XIONG Lei DONG Honghui LI Jianzhi WANG Wei FAN Wei qin hongfeng Beijing Jiaotong University Beijing 100044China German Aerospace Center(DLR) Münchner Strasse 2082234 WesslingGermany Aalborg University Aalborg 9220Denmark Xi’an R&D Center ZTE CorporationXi’an 710114China

The fifth generation(5G)communication has been a hotspot of research in recent years,and both research institutions and industrial enterprises put a lot of interests in 5G communications at some new frequency *** this paper,we investigate the radio channels of 5G systems below 6 GHz according to the 5G communication requirements and *** measurements were conducted on the campus of Beijing Jiaotong University,China at two key optional frequency bands below 6 *** using the measured data,we analyzed key channel parameters at 460 MHz and 3.5 GHz,such as power delay profile,path loss exponent,shadow fading,and delay *** results are helpful for the 5G communication system design.

关键词： channel measurement 5G channel characterization

Constraints on the primordial curvature power spectrum by pulsar timing array data:a polynomial parameterization approach

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Communications in Theoretical Physics 2024年第1期76卷 96-104页

作者： qin Fei School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalarinduced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power *** effectively model this peak,we apply the Taylor expansion to parameterize *** the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data *** constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.

关键词： pulsar timing array scalar-induced gravitational waves inflation

Numerical study on the blocking effect of skin on Flash-Ball Impact and damage assessment

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Defence Technology（防务技术） 2024年第3期33卷 532-545页

作者： Dihua Ouyang Chunwei qin Xiaowen qin Qiantao Zhang Xingyu Liu Xi'an University of Architecture and Technology Xi'an 710055China Analysis and Testing Center Xi'an University of Architecture and TechnologyXi'an 710055China Engineering University of PAP Xi'an 710086China

To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy *** on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are *** corridor curve and the energy transfer and diffusion are analyzed and *** safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration ***,the safe shooting distance is *** results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response *** energy transfer and action time of medium and low-speed impact may cause greater *** fat layer is the largest energy absorption *** minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.

关键词： KIPs Blunt strike Biomechanical response Damage analysis

Limit state analysis of rigid retaining structures against seismically induced passive failure in heterogeneous soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1095-1105页

作者： Jianfeng Zhou Changbing qin College of Civil Engineering Huaqiao UniversityXiamen362021China School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing400045China

Soils are not necessarily uniform and may present linearly varied or layered characteristics,for example the backfilled soils behind rigid retaining *** the presence of large lateral thrust imposed by arch bridge,passive soil failure is possible.A reliable prediction of passive earth pressure for the design of such wall is challenging in complicated soil strata,when adopting the conventional limit analysis *** order to overcome the challenge for generating a kinematically admissible velocity field and a statically allowable stress field,finite element method is incorporated into limit analysis,forming finiteelement upper-bound(FEUB)and finite-element lower-bound(FELB)***-static,original and modified pseudo-dynamic approaches are adopted to represent seismic acceleration *** generating feasible velocity and stress fields within discretized elements based on specific criteria,FEUB and FELB formulations of seismic passive earth pressure(coefficient K_(P))can be derived from work rate balance equation and stress *** to an interior point algorithm,optimal upper and lower bound solutions are *** proposed FEUB and FELB procedures are well validated by limit equilibrium as well as lower-bound and kinematic *** studies are carried out to investigate the effects of influential factors on seismic K_(P).Notably,true solution of K_(P) is well estimated based on less than 5%difference between FEUB and FELB solutions under such complex scenarios.

关键词： Retaining wall Passive earth pressure Earthquakes Finite-element limit-analysis methods

AI for Supporting the Freedom of Drawing

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Machine Intelligence Research 2024年第1期21卷 63-88页

作者： Xiaohua Sun Juexiao qin College of Design and Innovation Tongji UniversityShanghai 200082China

Artificial intelligence(AI)has recently been developing rapidly in image processing and *** is not only starting to take over repetitive and tedious tasks but is also involved in creative *** is one of the areas with the greatest potential for collaboration between humans and *** is an important approach to express various information,but due to the lack of appropriate knowledge and skills,ordinary people without long-time training are unable to draw *** there have been various attempts at human-AI collaboration in drawing,it is difficult for researchers to consider the wide variety of specific problems and develop univer-sal methods due to the openness,improvisation,and individuality of *** this paper,we first analysed the contents of drawing and the general creation process in ***,we have described a mechanism for using AI to enable people to regain the freedom of drawing ***,we have developed a framework that describes methods for analysing specific problems and quickly finding solutions by building connections between the influencing factors in drawing,the demands of humans,and possible implementa-tion *** framework also reveals a broad scope of possibilities for applying AI to support people in drawing.

关键词： Intention understanding drawing support drawing art human-artificial intelligence(AI)collaboration

The Coarse l^(p)-Novikov Conjecture and Banach Spaces with Property(H)

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 193-220页

作者： Huan WANG qin WANG Research Center for Operator Algebras School of Mathematical SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of MEA Ministry of Educationand Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,for 1

关键词： The coarse l^(p)-Novikov conjecture Banach spaces with Property(H) Coarse geometry K-Theory

Roles of Upper-Level Descending Inflow in Moat Development in Simulated Tropical Cyclones with Secondary Eyewall Formation

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Advances in Atmospheric Sciences 2024年第6期41卷 1100-1114页

作者： Nannan qin Liguang WU Nanjing Joint Institute for Atmospheric Sciences Nanjing 210041China Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030China Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Innovation Center of Ocean and Atmosphere System Zhuhai Fudan Innovation Research InstituteZhuhai 518057China

This study investigated the effects of upper-level descending inflow(ULDI)associated with inner-eyewall convection on the formation of the moat in tropical cyclones(TCs)with secondary eyewall formation(SEF).In our numerical experiments,a clear moat with SEF occurred in TCs with a significant ULDI,while no SEF occurred in TCs without a significant *** eyewall convection developed more vigorously in the control run.A ULDI occurred outside the inner-eyewall convection,where it was symmetrically *** ULDI was initially triggered by the diabatic warming released by the inner eyewall and later enhanced by the cooling below the anvil *** ULDI penetrated the outer edge of the inner eyewall with relatively dry air and prevented excessive solid-phase hydrometeors from being advected further *** produced extensive sublimation cooling of falling hydrometeors between the eyewall and the outer *** sublimation cooling resulted in negative buoyancy and further induced strong subsidence between the eyewall and the outer *** a result,a clear moat was *** of the moat in the ongoing SEF prevented the outer rainband from moving farther inward,helping the outer rainband to symmetrize into an outer *** the sensitivity experiment,no significant ULDI formed since the eyewall convection was weaker,and the eyewall anvil developed relatively lower,meaning the formation of a moat and thus an outer eyewall was less *** study suggests that a better-represented simulation of inner-eyewall convective structures and distribution of the solid-phase hydrometeors is important to the prediction of SEF.

关键词： tropical cyclone secondary eyewall formation upper-level descending inflow eyewall convection

Towards data-efficient mechanical design of bicontinuous composites usinggenerative AI

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 57-64页

作者： Milad Masrouri Zhao qin Department of Civil and Environmental Engineering Syracuse UniversitySyracuseNY 13244USA Laboratory for Multiscale Material Modelling Syracuse UniversitySyracuseNY 13244USA The BioInspired Institute Syracuse UniversitySyracuseNY 13244USA

The distribution of material phases is crucial to determine the composite’s mechanical *** the full structure-mechanics relationship of highly ordered material distributions can be studied with finite number of cases,this relationship is difficult to be revealed for complex irregular distributions,preventing design of such material structures to meet certain mechanical *** noticeable developments of artificial intelligence(AI)algorithms in material design enables to detect the hidden structure-mechanics correlations which is essential for designing composite of complex *** is intriguing how these tools can assist composite ***,we focus on the rapid generation of bicontinuous composite structures together with the stress distribution in *** find that generative AI,enabled through fine-tuned Low Rank Adaptation models,can be trained with a few inputs to generate both synthetic composite structures and the corresponding von Mises stress *** results show that this technique is convenient in generating massive composites designs with useful mechanical information that dictate stiffness,fracture and robustness of the material with one model,and such has to be done by several different experimental or simulation *** research offers valuable insights for the improvement of composite design with the goal of expanding the design space and automatic screening of composite designs for improved mechanical functions.

关键词： Generative artificial intelligence Stable diffusion Composite design Phase field model Molecular dynamics simulation