检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

基于灰度与关键帧光流检测的视频异常判断

电子器件 2019年第3期42卷 718-721页

作者：张霞贺正然莆田学院信息工程学院福建莆田351100 东南大学信息科学与工程学院南京210096

视频监控系统在日常生活中日益普及,为了实现监控视频的智能分析,利用背景差分法检测并提取关注的前景目标,再结合光流算法分析目标的运动方向和强度。为了提升视频分析效率,先利用帧差欧几里得距离法计算帧与帧之间的相似度,提取视频... 详细信息

视频监控系统在日常生活中日益普及,为了实现监控视频的智能分析,利用背景差分法检测并提取关注的前景目标,再结合光流算法分析目标的运动方向和强度。为了提升视频分析效率,先利用帧差欧几里得距离法计算帧与帧之间的相似度,提取视频序列的关键帧,并提出了一种运算量小检测效果较好的基于图像灰度化的背景差分法进一步提取关键帧的前景目标,最后用光流法计算得到目标的光流矢量和强度信息,为监控视频的异常判断提供依据。

关键词：灰度值背景差分法帧差欧几里得距离光流法

基于Transformer编码器的多级表示与融合特征输入的语音情感识别方法

在线全文

学校读者我要写书评

暂无评论

Journal of Southeast University(English Edition) 2023年第1期39卷 68-73页

作者：贺正然沈起帆吴佳欣徐梦瑶赵力东南大学信息科学与工程学院南京210096 东南大学微电子学院南京210096 School of Computer Science and Software Engineering University of StirlingStirling FK94LAUK

为了提高语音情感识别的准确度,探讨了将Transformer应用于语音情感识别的可能性.将对数梅尔尺度谱图及其一阶差分特征相融合作为输入,使用Transformer来提取分层语音表示,分析注意头个数和Transformer编码器层数的变化对识别精度的影响... 详细信息

为了提高语音情感识别的准确度,探讨了将Transformer应用于语音情感识别的可能性.将对数梅尔尺度谱图及其一阶差分特征相融合作为输入,使用Transformer来提取分层语音表示,分析注意头个数和Transformer编码器层数的变化对识别精度的影响.结果表明,在ABC、CASIA、DES、EMODB和IEMOCAP语音情感数据库上,相比以MFCC为特征的Transformer,所提模型的精度分别提高了13.98%、8.14%、24.34%、8.16%和20.9%.该模型表现优于递归神经网络(RNN)、卷积神经网络(CNN)、Transformer等其他模型.

关键词：语音情感识别 Transformer 多头注意力机制融合特征

基于IMU传感器与深度度量学习的人体行为识别算法

在线全文

学校读者我要写书评

暂无评论

移动通信 2024年第3期48卷 131-136页

作者：时尚何正燃董恒南京邮电大学通信与信息工程学院江苏南京210023

人体行为识别可以定义为通过一系列观察和周围环境来确定一个人的各种姿势和日常活动。很多研究尝试将深度学习技术用于HAR中,然而,现有的基于DL的HAR方法存在复杂度较高、算力需求大和泛化性与鲁棒性不足的问题。为了解决上述问题,围... 详细信息

人体行为识别可以定义为通过一系列观察和周围环境来确定一个人的各种姿势和日常活动。很多研究尝试将深度学习技术用于HAR中,然而,现有的基于DL的HAR方法存在复杂度较高、算力需求大和泛化性与鲁棒性不足的问题。为了解决上述问题,围绕基于智能手机内置IMU传感器的HAR方法,提出了一种名为RMDML的HAR方法,该方法结合了轻量化神经网络Res-MLP和深度度量学习的特征嵌入技术,旨在提取具有可分离性与可判别性的泛化特征,从而提高模型识别性能和泛化性能。RMDML模型在公开数据集UCI HAR上取得了97.26%的准确率,高于几种常见的HAR算法,证明了所提出方法的有效性。

关键词：人体行为识别惯性测量单元传感器残差多层感知机度量学习

一种改进的声发射模板识别流程及其在大尺度页岩水力压裂主被动观测实验中的应用研究

在线全文

学校读者我要写书评

暂无评论

地球物理学报 2023年第10期66卷 4386-4401页

作者：李德康贺正然张作冬邹雨时王小琼谢凡中国地震局地球物理研究所震源物理重点实验室北京100081 东南大学信息科学与工程学院南京210096 中国石油大学(北京)非常规油气科学技术研究院北京102249

提出一种改进的实验室声发射模板识别流程.该流程联合RMS-AIC算法优化了模板事件的检测效果,将一种改进的绝对离差中位数(观测数据的二分位数与MAD的和)应用于不同时段RMS与互相关序列的动态阈值的设置中,并对声发射模板事件与多通道连... 详细信息

提出一种改进的实验室声发射模板识别流程.该流程联合RMS-AIC算法优化了模板事件的检测效果,将一种改进的绝对离差中位数(观测数据的二分位数与MAD的和)应用于不同时段RMS与互相关序列的动态阈值的设置中,并对声发射模板事件与多通道连续波形数据的互相关叠加方式进行了改进,以避免弱初至延迟量不准确对叠加异常点的影响.我们开展了大尺度龙马溪组页岩水力压裂过程的主动源超声检测与声发射事件联合观测实验,并将该流程应用于主、被动连续观测数据中声发射信号的识别.研究结果表明:利用本文提出的流程检测出1720个声发射信号,数量比声发射模板信号大约多5.54倍.利用更为完备的声发射目录,我们观测到页岩水力压裂过程中的主压裂点大约发生在152 s,且压裂后早期3 s内声发射率呈现出较慢的幂率衰减(p=0.130),而后以较快速率(p=1.403)衰减至稳定值.此外,我们对多种震相拾取算法的比较、声发射的频-幅分布特征等方面开展了讨论.这一新的声发射识别流程可以有效提高在主、被动联合观测下的声发射识别效果,完备水力压裂过程中声发射的时序分布特征,为页岩气开采及风险评估的实验室研究提供有效支撑.

关键词：模板匹配水力压裂主、被动连续记录声发射活动性频-幅特征

维普期刊数据库博看期刊

Wi-Fi环境下基于注意力机制及深度学习的鲁棒被动感知技术

在线全文

学校读者我要写书评

暂无评论

移动通信 2022年第7期46卷 40-45页

作者：何正燃张茜茜王禹杨洁南京邮电大学通信与信息工程学院江苏南京210003

随着无线通信系统的不断发展,基于Wi-Fi的被动感知识别技术由于其廉价的部署费用以及广泛的部署空间,逐渐成为主流的感知手段。但是在如今复杂的电磁环境中,传统感知识别的方法会面临识别性能差、鲁棒性弱以及智能化程度不足等问题。针... 详细信息

随着无线通信系统的不断发展,基于Wi-Fi的被动感知识别技术由于其廉价的部署费用以及广泛的部署空间,逐渐成为主流的感知手段。但是在如今复杂的电磁环境中,传统感知识别的方法会面临识别性能差、鲁棒性弱以及智能化程度不足等问题。针对这些情况,利用注意力机制和深度学习的方法,提出了一种新型的基于CSI的被动感知方法,即ConvA BLSTM。该方法是CNN与BLSTM的组合,利用CNN提取CSI中的空间信息,利用BLSTM提取CSI中的时间信息,并且引入注意力机制自适应调整网络参数权重。通过深度学习的引入,可以提高传统感知识别方法的性能,而注意力机制的引入则可以很好地解决模型鲁棒性弱以及自适应性较差等问题。最后,从识别精度以及模型鲁棒性两个方面对所提出的方法进行了实验验证。实验结果表明,与传统的单一CNN或者单一BLSTM网络相比,所提出的方法在精度上有着3%左右的准确度提升,并且在鲁棒性方面,在识别目标和识别场景改变的情况下依旧能保持96%左右的准确度。

关键词：基于Wi-Fi的被动感知深度神经网络注意力机制信道状态信息

The ferroptosis activity is associated with neurological recovery following chronic compressive spinal cord injury

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第11期18卷 2482-2488页

作者： zhengran Yu Xing Cheng Wenxu Pan Cheng Yu Yang Duan Department of Spine Surgery Orthopedics Center of Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Gastroenterology Guangzhou Women and Children’s Medical CenterJinan UniversityGuangzhouGuangdong ProvinceChina Department of Spine Surgery Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Chronic compressive spinal cord injury in compressive cervical myelopathy conditions can lead to rapid neurological deterioration in the early phase,followed by partial self-recovery,and ultimately an equilibrium state of neurological *** is a crucial pathological process in many neurodegenerative diseases;however,its role in chro nic compressive spinal cord injury remains *** this study,we established a chronic compressive spinal cord injury rat model,which displayed its most severe behavioral and electrophysiological dysfunction at 4 wee ks and partial recovery at 8 weeks after *** RNA sequencing data identified enriched functional pathways,including ferroptosis,presynapse,and postsynaptic membrane activity at both 4 and 8 wee ks following chro nic compressive spinal co rd *** nsmission electron microscopy and malondialdehyde quantification assay confirmed that ferroptosis activity peaked at 4 weeks and was attenuated at 8 weeks after chronic *** ptosis activity was negatively correlated with behavioral ***,quantitative polymerase chain reaction,and western blotting showed that expression of the anti-ferroptosis molecules,glutathione peroxidase 4(GPX4) and MAF BZIP transcription factor G(MafG),in neuro ns was suppressed at 4 weeks and upregulated at 8 weeks following spinal co rd *** was a positive correlation between the expression of these two molecules,suggesting that they may work together to contribute to functional recovery following chronic compressive spinal cord *** conclusion,our study determined the genome-wide expression profile and fe rroptosis activity of a consistently compressed spinal cord at different time *** results showed that anti-fe rroptosis genes,specifically GPX4 and MafG,may be involved in spontaneous neurological recovery at 8 weeks of chronic compressive spinal cord *** findings contribute to a better understanding of t

关键词： chronic spinal cord compression compressive cervical myelopathy ferroptosis genome-wide transcriptome glutathione peroxidase 4(GPX4) MAF BZIP transcription factor G(MafG) neurological function

Epidemic Characteristics of Human Rabies—China,2016–2020

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2021年第39期3卷 819-821页

作者： zhengran Liu Min Liu Xiaoyan Tao Wuyang Zhu School of Public health Baotou Medical CollegeBaotouInner Mongolia Autonomous RegionChina NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina.

Introduction:The epidemiological characteristics of human rabies in China in 2016–2020 were analyzed in order to provide the scientific basis for the formulation of the prevention and control policy of rabies at next ***:The data of China’s National Notifiable Disease Reporting System(NNDRS)from 2016 to 2020 were collected and analyzed by using a descriptive epidemiology ***:A total of 2,074 cases of human rabies were reported from 2016–2020 in China,there were year over year decreases in total number of *** rabies appeared throughout the year,among which the highest in incidence happened from August to October,while March and December months were months in which the epidemic was ***:Though decreases were observed for human rabies in China,further steps should be taken to maintain these *** should be strengthened and the immunity of dogs should be prioritized to control this situation from the *** addition,all reported cases should be monitored and reported to achieve the accurate prevention and control.

关键词： prevention epidemiology Human

Microstructural Evolution and Anisotropic Weakening Mechanism of ZK60 Magnesium Alloy Processed by Isothermal Repetitive Upsetting Extrusion

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 839-852页

作者： zhengran Liu Xi Zhao Kai Chen Siqi Wang Xianwei Ren Zhimin Zhang Yong Xue School of Mechanical and Electrical Engineering North University of ChinaTaiyuan030051China Engineering Technology Research Center for Integrated Precision Forming of Shanxi Province North University of ChinaTaiyuan030051China

The isothermal repetitive upsetting extrusion(RUE)was implemented to process ZK60 magnesium alloy at 380℃.Then,the relationship between the microstructural characters,including grain refinement and texture evolution,and the mechanical performance of the alloy was *** showed that after 3 passes of RUE,the average grain size was refined from 115.0 to 26.5μm,which was mainly caused by the continuous dynamic recrystallization and discontinuous dynamic ***,the elongation of the alloy increased from 13.8 to 21.6%,and the superplasticity(142%)of the alloy has been achieved in the following high temperature tensile test,which is very beneficial for the further processing of the alloy into *** particular,the alloy formed a distinctive texture distributed betweenand,which was greatly related to the Schmid factor of extrusion direction(ED)and transverse direction(TD).This texture changed the initiation ability of basal and prismatic slip in both directions and inhibited the initiation of partial tensile twinning in TD;thus,the anisotropy in both directions was *** expected,the tensile yield strength difference decreased from25.9 to 3.4 MPa,but it was used as the cost of tensile yield strength in ED.

关键词： Severe plastic deformation Repetitive upsetting extrusion ZK60 alloy Microstructure Mechanical properties

One-step growth of ultrathin CoSe_(2)nanobelts on N-doped MXene nanosheets for dendrite-inhibited and kinetic-accelerated lithium-sulfur chemistry

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2024年第13期69卷 2059-2070页

作者： Chuanliang Wei zhengran Wang Peng Wang Xinlu Zhang Xuguang An Jinkui Feng Baojuan Xi Shenglin Xiong School of Chemistry and Chemical Engineering School of Materials Science and EngineeringShandong UniversityJinan 250100China School of Mechanical Engineering Chengdu UniversityChengdu 610106China

The practical application of lithium–sulfur(Li–S)batteries is inhibited by the shuttle effect of lithium polysulfides(LiPSs)and slow polysulfide redox kinetics on the S cathode as well as the uncontrollable growth of dendrites on the Li metal ***,both cathode and anode sides must be considered when modifying LiS ***,two-dimensional(2D)ultrathin CoSe_(2)nanobelts are in situ grown on 2D N-doped MXene nanosheets(CoSe_(2)@N-MXene)via one-step solvothermal process for the first *** to its unique 2D/2D structure,CoSe_(2)@N-MXene can be processed to crumpled nanosheets by freeze-drying and flexible and freestanding films by vacuum *** crumpled CoSe_(2)@NMXene nanosheets with abundant active sites and inner spaces can act as S hosts to accelerate polysulfide redox kinetics and suppress the shuttle effect of LiPSs owing to their strong adsorption ability and catalytic conversion effect with ***,the CoSe_(2)@N-MXene film(CoSe_(2)@NMF)can act as a current collector to promote uniform Li deposition because it contains lithiophilic CoSe_(2)and N *** the systematic effect of CoSe_(2)@N-MXene on S cathode and Li metal anode,the electrochemical and safety performance of Li–S batteries are ***_(2)@NMF also shows excellent storage performances in flexible energy storage devices.

关键词： Ultrathin CoSe_(2)nanobelts N-doped MXene nanosheets In situ growth Flexible MXene-based films Li-S batteries