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问卷分割的有效性和最优样本量分配方法研究

数理统计与管理 2023年第4期42卷 611-625页

作者：王小宁媒体融合与传播国家重点实验室(中国传媒大学) 北京100024 中国传媒大学数据科学与智能媒体学院北京100024

近年来,随着调查问卷的无回答率逐渐增高,导致问卷调查的费用提高和精度降低,而问卷分割技术因其能够提高抽样效率而渐渐成为调查机构的备选之一。本文在结合问卷分割技术的基础上,分析了问卷分割技术对普通调查的优势与调查变量间的相... 详细信息

近年来,随着调查问卷的无回答率逐渐增高,导致问卷调查的费用提高和精度降低,而问卷分割技术因其能够提高抽样效率而渐渐成为调查机构的备选之一。本文在结合问卷分割技术的基础上,分析了问卷分割技术对普通调查的优势与调查变量间的相关系数、调查的固定花费、不同数据项之间的方差之比以及不同数据项之间的调查费用之比。同时结合问卷分割方法的优势得出了在方差限制的情况下最小化花费和在经费一定的情况下最小化方差两种情况下的最优样本分配方案,并结合模拟数据进行了对比分析。为相关机构采用问卷分割技术提升抽样效率提供了一个可行的参考方案。

关键词：问卷分割样本量抽样效率

Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds

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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556,I0013页

作者： Miao Xie xiao-Rong wang Zhan-Hua wang He-Sheng Xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan UniversityChengdu610065China School of Petrochemical Engineering Liaoning Petrochemical UniversityFushun113001China

Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic *** main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance *** this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate *** calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea *** verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer *** self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea *** separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance *** hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Self-healing polymer Dynamic covalent bond

Resilience assessment and optimization method of city road network in the post-earthquake emergency period

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 765-779页

作者： wang Haoran xiao Jia Li Shuang Zhai Changhai Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150090China

The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social *** improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is *** road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,*** road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the *** optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road *** optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.

关键词： city road network post-earthquake emergency period traffic demand resilience evaluation optimization model

Parallel Implementation of the CCSDS Turbo Decoder on GPU

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China Communications 2024年第10期21卷 70-77页

作者： Liu Zhanxian Liu Rongke Zhang Haijun wang ning Sun Lei wang Jianquan School of Computer&Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services Institute of Artificial IntelligenceUniversity of Science and Technology BeijingBeijing 100083China School of Information Engineering Zhengzhou UniversityZhengzhou 450001China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China

This paper presents a software turbo decoder on graphics processing units(GPU).Unlike previous works,the proposed decoding architecture for turbo codes mainly focuses on the Consultative Committee for Space Data Systems(CCSDS)***,the information frame lengths of the CCSDS turbo codes are not suitable for flexible sub-frame parallelism *** mitigate this issue,we propose a padding method that inserts several bits before the information frame *** obtain low-latency performance and high resource utilization,two-level intra-frame parallelisms and an efficient data structure are *** presented Max-Log-Map decoder can be adopted to decode the Long Term Evolution(LTE)turbo codes with only small *** proposed CCSDS turbo decoder at 10 iterations on NVIDIA RTX3070 achieves about 150 Mbps and 50Mbps throughputs for the code rates 1/6 and 1/2,respectively.

关键词： CCSDS CUDA GPU parallel decoding turbo codes

Distortion-aware beamforming design for multi-beam satellite communications with nonlinear power amplifiers

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Science China(Information Sciences) 2024年第6期67卷 359-369页

作者： Xiang xiao Li YOU Kezhi wang Xiqi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Computer Science Brunel University London

Hardware components can cause different impairments, including power amplifier(PA) nonlinearities, which inevitably impact the system performance of satellite communications(SATCOM). In this work, we consider a multi-beam SATCOM downlink system and investigate the distortion-aware beamforming scheme with the characteristics of PA non-linearities. Notably, we aim to maximize the resource efficiency(RE), defined as the weighted sum of energy efficiency(EE) with spectral efficiency(SE), to obtain a flexible EE-SE tradeoff while accounting for the characteristics of PA distortion and the total power *** that the optimization objective is a sum of ratios and the high non-convexity involved in constraints,we propose an efficient approach that exploits the quadratic transformation, the Lagrange multiplier method,and the gradient ascent approach to handle this issue. Simulation results demonstrate the effectiveness of the distortion-aware beamforming approach in achieving the EE-SE tradeoff and exhibit a substantial RE performance gain over the conventional approach with ideal linear PAs assumed at the satellite transmitters.

关键词： multi-beam satellite communications nonlinear power amplifier energy and spectral efficiency tradeoff resource efficiency robust beamforming

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小域估计在问卷分割中的应用研究

统计与信息论坛 2021年第9期36卷 3-10页

作者：王小宁中国传媒大学数据科学与智能媒体学院北京100024

问卷分割设计在设计上能够通过减少问卷长度来减少调查时间,从而提高问卷回答率和提升调查效率,近年来成为国内外政府部门和调研机构用来提升调查数据质量的一种方法。在涉及对样本数据的估计中,通过问卷分割得到的样本在某些域上往往... 详细信息

问卷分割设计在设计上能够通过减少问卷长度来减少调查时间,从而提高问卷回答率和提升调查效率,近年来成为国内外政府部门和调研机构用来提升调查数据质量的一种方法。在涉及对样本数据的估计中,通过问卷分割得到的样本在某些域上往往存在样本量很少的情况,采用小域估计方法对问卷分割设计得到的样本进行参数估计,通过理论推导和模拟研究表明,使用小域估计方法对分割问卷得到的数据进行参数估计,从偏差、相对偏差、估计的均方误差和相对有效性等衡量指标上优于多重插补法得到的估计结果,能显著提高统计调查的精度。但是,当研究的目标变量间存在较强的相关关系时,就需要进一步优化该方法从而得到更精确的估计。

关键词：问卷分割小域估计估计效率无回答率

Nickel-Catalyzed Regiodivergent Acylzincation of Styrenes with Organozincs and CO

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Chinese Journal of Chemistry 2024年第6期42卷 599-604页

作者： Chenglong wang ning Liu Xianqing Wu Jingping Qu Yifeng Chen Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237 China Dedicated to the Special Issue of C1 Chemistry.

Transition metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C ***,the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction,which greatly increases the horizon of carbometallation ***,we report a nickel-catalyzed regiodivergent acylzincation of o-cyano cinnamate ester and o-cyano styrene,in which the cyano moiety intramolecularly captures zinc intermediates to trigger the tandem cyclization *** protocol features mild conditions,broad substrate scope and excellent functional group tolerance,thus affording a diverse array of highly functionalized carbocyclic compounds.

关键词： Carbonylation Carbometallation Styrene Nickel Cyclization

Extraction of Acoustic Normal Mode Depth Functions Using Range-Difference Method with Vertical Linear Array Data

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Journal of Ocean University of China 2024年第4期23卷 871-882页

作者： GAO Siyu LI Weilu ZHANG Yinquan LI xiaolei wang ning College of Marine Technology Ocean University of ChinaQingdao 266100China National Marine Data and Information Service Tianjin 300171China

Data-derived normal mode extraction is an effective method for extracting normal mode depth functions in the absence of marine environmental ***,when the corresponding singular vectors become nonunique when two or more singular values obtained from the cross-spectral density matrix diagonalization are nearly equal,this results in unsatisfactory extraction outcomes for the normal mode depth *** address this issue,we introduced in this paper a range-difference singular value decomposition method for the extraction of normal mode depth *** performed the mode extraction by conducting singular value decomposition on the individual frequency components of the signal's cross-spectral density *** was achieved by using pressure and its range-difference matrices constructed from vertical line array *** proposed method was validated using simulated *** addition,modes were successfully extracted from ambient noise.

关键词： range difference depth function extraction normal mode

The connection of phytoplankton biomass in the Marguerite Bay polynya of the western Antarctic Peninsula to the Southern Annular Mode

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Acta Oceanologica Sinica 2024年第1期43卷 35-47页

作者： ning Jiang Zhaoru Zhang Ruifeng Zhang Chuning wang Meng Zhou School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

Antarctic coastal polynyas are biological hotspots in the Southern Ocean that support the abundance of hightrophic-level predators and are important for carbon cycling in the high-latitude *** this study,we examined the interannual variation of summertime phytoplankton biomass in the Marguerite Bay polynya(MBP)in the western Antarctic Peninsula area,and linked such variability to the Southern Annular Mode(SAM)that dominated the southern hemisphere extratropical climate *** satellite data,atmosphere reanalysis products and numerical simulations,we found that the interannual variation of summer chlorophyll-a(Chl-a)concentration in the MBP is significantly and negatively correlated with the spring SAM index,and weakly correlated with the summer SAM *** negative relation between summer Chl-a and spring SAM is due to weaker spring vertical mixing under a more positive SAM condition,which would inhibit the supply of iron from deep layers into the surface euphotic *** negative relation between spring mixing and spring SAM results from greater precipitation rate over the MBP region in positive SAM phase,which leads to lower salinity in the ocean surface *** coupled physical-biological mechanisms between SAM and phytoplankton biomass revealed in this study is important for us to predict the future variations of phytoplankton biomasses in Antarctic polynyas under climate change.

关键词： Marguerite Bay polynya phytoplankton biomass Southern Annular Mode mixed layer depth interannual variation