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用于语音降噪的级联滤波器的设计与实现

电子器件 2013年第6期36卷 810-813页

作者：包永强南京工程学院通信工程学院南京210096

将ETSI ES 202 050 V.1.1.3版本规定的Mel域上的两级维纳滤波结构推广到分数Mel域上,基于3周期的离散分数余弦变换,提出了分数Mel域上的两级维纳滤波结构,获得了性能的提高;针对以上两种方法的计算量较大和引入了时域截断噪声等缺点,提... 详细信息

将ETSI ES 202 050 V.1.1.3版本规定的Mel域上的两级维纳滤波结构推广到分数Mel域上,基于3周期的离散分数余弦变换,提出了分数Mel域上的两级维纳滤波结构,获得了性能的提高;针对以上两种方法的计算量较大和引入了时域截断噪声等缺点,提出了分数余弦变换域上的两级最佳线性滤波。理论分析和实验结果表明,该算法具有明显的降噪作用,能够应用于语音识别系统前端处理中。

关键词：语音信号降噪分数余弦变换

Deep Energies for Estimating Three-Dimensional Facial Pose and Expression

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Communications on Applied Mathematics and Computation 2024年第2期6卷 837-861页

作者： Jane Wu Michael bao Xinwei Yao Ronald Fedkiw Department of Computer Science Stanford University353 Jane Stanford WayStanfordCA 94305USA Epic Games 620 Crossroads BlvdCaryNC 27518USA

While much progress has been made in capturing high-quality facial performances using motion capture markers and shape-from-shading,high-end systems typically also rely on rotoscope curves hand-drawn on the *** curves are subjective and difficult to draw consistently;moreover,ad-hoc procedural methods are required for generating matching rotoscope curves on synthetic renders embedded in the optimization used to determine three-dimensional(3D)facial pose and *** propose an alternative approach whereby these curves and other keypoints are detected automatically on both the image and the synthetic renders using trained neural networks,eliminating artist subjectivity,and the ad-hoc procedures meant to mimic *** generally,we propose using machine learning networks to implicitly define deep energies which when minimized using classical optimization techniques lead to 3D facial pose and expression estimation.

关键词： Numerical optimization Neural networks Motion capture Face tracking

Effect of the Particle Packing Configuration on Fixed Bed Performance

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 152-160页

作者： Li Ziqi bao Di Zhou Han Tang Xiaojin SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Fixed-bed reactors are generally considered the optimal choice for numerous multi-phase catalytic reactions due to their excellent performance and ***,conventional fixed beds often encounter challenges related to inadequate mass transfer and a high pressure drop caused by the non-uniform void fraction *** enhance the overall performance of fixed beds,the impact of different packing configurations on performance was *** and simulation methods were used to investigate the fluid flow and mass transfer performances of various packed beds under different flow *** was found that structured beds exhibited a significantly lower pressure drop per unit length than conventional packed ***,the packing configurations had a critical role in improving the overall performance of fixed ***,structured packed beds,particularly the H-2 packing configuration,effectively reduced the pressure drop per unit length and improved the mass transfer *** H-2 packing configuration consisted of two parallel strips of particles in each layer,with strips arranged perpendicularly between adjacent layers,and the spacing between the strips varied from layer to layer.

关键词： packing configurations fixed bed Computational Fluid Dynamics simulation pressure drop mass transfer

Density-Functional Theories for Polyelectrolyte Systems

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Chinese Journal of Polymer Science 2024年第9期42卷 1302-1312,I0006页

作者： Jia-Wei Zhang Yu-Hang Zhang bao-Hui Li Qiang Wang School of Physics Nankai UniversityTianjin90001China Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Polymer density-functional theories(PDFTs)have distinct advantages in the study of polyelectrolyte(PE)systems over experiments and molecular *** we give an introductory review of some PDFTs recently developed for PE *** start with a general formalism of PDFTs and its relation to the widely used polymer self-consistent field theory(SCFT),then explain the various correlations that are neglected in SCFT but can be accounted for in PDFTs,including those due to the excluded-volume interaction and chain connectivity of uncharged polymers,the electrostatic correlations of small ions,and the chain correlations in *** also list some applications of PDFTs for PE systems,and finally give some perspectives on future *** hope that our review can attract more researchers to apply and further develop PDFTs as a promising class of theoretical and computational tools.

关键词： Polymer density-functional theories Polyelectrolytes Correlations

The advantages of multi-level omics research on stem cell-based therapies for ischemic stroke

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Neural Regeneration Research 2024年第9期19卷 1998-2003页

作者： Yiqing Wang Chuheng Chang Renzhi Wang Xiaoguang Li Xinjie bao 4+4 Doctor Medical Program Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Department of Neurosurgery Peking Union Medical College HospitalPeking Union Medical CollegeChinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory for Biomaterials and Neural Regeneration School of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina

Stem cell transplantation is a potential therapeutic strategy for ischemic stroke. However, despite many years of preclinical research, the application of stem cells is still limited to the clinical trial stage. Although stem cell therapy can be highly beneficial in promoting functional recovery, the precise mechanisms of action that are responsible for this effect have yet to be fully elucidated. Omics analysis provides us with a new perspective to investigate the physiological mechanisms and multiple functions of stem cells in ischemic stroke. Transcriptomic, proteomic, and metabolomic analyses have become important tools for discovering biomarkers and analyzing molecular changes under pathological conditions. Omics analysis could help us to identify new pathways mediated by stem cells for the treatment of ischemic stroke via stem cell therapy, thereby facilitating the translation of stem cell therapies into clinical use. In this review, we summarize the pathophysiology of ischemic stroke and discuss recent progress in the development of stem cell therapies for the treatment of ischemic stroke by applying multi-level omics. We also discuss changes in RNAs, proteins, and metabolites in the cerebral tissues and body fluids under stroke conditions and following stem cell treatment, and summarize the regulatory factors that play a key role in stem cell therapy. The exploration of stem cell therapy at the molecular level will facilitate the clinical application of stem cells and provide new treatment possibilities for the complete recovery of neurological function in patients with ischemic stroke.

关键词： ischemic stroke mesenchymal stem cells metabolomics multilevel omics neural stem/progenitor cells neuroinflammation pathophysiology proteomics stem cell therapy transcriptomes

Improving the accuracy of precipitation estimates in a typical inland arid area of China using a dynamic Bayesian model averaging approach

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Journal of Arid Land 2024年第3期16卷 331-354页

作者： XU Wenjie DING Jianli bao Qingling WANG Jinjie XU Kun College of Geography and Remote Sensing Sciences Xinjiang UniversityUrumqi 830017China Key Laboratory of Smart City and Environment Modelling of Higher Education Institute Xinjiang UniversityUrumqi 830017China

Xinjiang Uygur Autonomous Region is a typical inland arid area in China with a sparse and uneven distribution of meteorological stations,limited access to precipitation data,and significant water *** and integrating precipitation datasets from different sources to accurately characterize precipitation patterns has become a challenge to provide more accurate and alternative precipitation information for the region,which can even improve the performance of hydrological *** study evaluated the applicability of widely used five satellite-based precipitation products(Climate Hazards Group InfraRed Precipitation with Station(CHIRPS),China Meteorological Forcing Dataset(CMFD),Climate Prediction Center morphing method(CMORPH),Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record(PERSIANN-CDR),and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis(TMPA))and a reanalysis precipitation dataset(ECMWF Reanalysis v5-Land Dataset(ERA5-Land))in Xinjiang using ground-based observational precipitation data from a limited number of meteorological *** on this assessment,we proposed a framework that integrated different precipitation datasets with varying spatial resolutions using a dynamic Bayesian model averaging(DBMA)approach,the expectation-maximization method,and the ordinary Kriging interpolation *** daily precipitation data merged using the DBMA approach exhibited distinct spatiotemporal variability,with an outstanding performance,as indicated by low root mean square error(RMSE=1.40 mm/d)and high Person's correlation coefficient(CC=0.67).Compared with the traditional simple model averaging(SMA)and individual product data,although the DBMA-fused precipitation data were slightly lower than the best precipitation product(CMFD),the overall performance of DBMA was more *** error analysis between DBMA-fused precipitation dataset and the more advanced Inte

关键词： precipitation estimates satellite-based and reanalysis precipitation dynamic Bayesian model averaging streamflow simulation Ebinur Lake Basin Xinjiang

Why lowland riparian trees are difficult to use for streamflow reconstruction

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Journal of Forestry Research 2024年第3期35卷 219-230页

作者： Xiaomei Peng Shengchun Xiao bao Yang Quanyan Tian Vladimir V.Shishov Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geography and Ocean Science Nanjing UniversityNanjing 210023People's Republic of China Institute of Fundamental Biology and Biotechnology Siberian Federal UniversityKrasnoyarskRussia 660041

Existing streamflow reconstructions based on tree-ring analysis mostly rely on species from upland,mainly montane areas,while lowland species(generally plain)areas are rarely *** limits the understanding of streamflow change history in the lowlands,which is an important basis for water resource *** study focused on Populus euphratica stands located along the main stream,eastern and western tributaries in the lower reaches of the Heihe River basin(HRb),in arid northwestern *** investigated how streamflow regulation interferes with ripar-ian trees in lowlands when they used for streamflow ***-ring width chronologies were developed and analyzed in conjunction with meteorological and hydrologic observation *** results show streamflow regulation leads in sharp fluctuations in the streamflow allocation between the eastern tributaries and western *** resulted in instability of the correlation between streamflow at the two tributaries and at the Zhengyixia hydrologic station,with corresponding fluctuations in radial growth of poplar trees on the banks of the two tributaries and at the *** regulation altered the natural patterns of seasonal streamflow below the station,changing the time window of poplar *** study provides useful insight into tree-ring width based streamflow reconstruction in the lowlands.

关键词： Tree-ring width-Dendrochronology Populus euphratica The Ejina Oasis Streamflow

Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials

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Journal of Energy Chemistry 2024年第1期88卷 213-222,I0005页

作者： Xinyou He Shilin Su bao Zhang Zhiming Xiao Zibo Zhang Xing Ou Engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083HunanChina Zhejiang Power New Energy Co.Ltd Zhuji 311899ZhejiangChina

Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary *** the arrangement of primary particles plays a very important role in the properties of Ni-rich *** disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is ***,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation *** finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are ***,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution ***,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic ***-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic *** precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes.

关键词： Ni-rich cathode Grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion

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基于微服务的软件信道仿真器架构设计与实现

南京工程学院学报:自然科学版 2023年第2期21卷 16-22页

作者：余雨杨洁包永强南京工程学院信息与通信工程学院江苏南京211167

快速构建第五代移动通信系统多样场景下的无线通信链路依赖于能模拟真实信道环境的信道仿真器.采用容器化、前后端分离以及开放接口技术,基于微服务设计与开发可扩展的软件无线信道仿真器,可实现信道存储、信道回放、信道建模、信道生... 详细信息

快速构建第五代移动通信系统多样场景下的无线通信链路依赖于能模拟真实信道环境的信道仿真器.采用容器化、前后端分离以及开放接口技术,基于微服务设计与开发可扩展的软件无线信道仿真器,可实现信道存储、信道回放、信道建模、信道生成、链路级仿真和系统级仿真等功能.该软件信道仿真器具备较好的可扩展性,用户无需在本地安装客户端和数据库,即可通过网页远程访问该软件信道仿真器,实现资源和数据共享.该信道仿真器可为通信系统的设计、验证和研究提供参考.

关键词：信道仿真器微服务信道生成链路级仿真系统级仿真