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一种融合多尺度动态注意力与1D-2D卷积的旋转机械声学故障轻量诊断方法
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作者 何新荣 杜小泽 +2 位作者 谭锐 蒋国安 徐超 《现代制造工程》 北大核心 2026年第2期143-150,共8页
针对旋转机械声学信号中存在的非平稳性强与噪声干扰显著等问题,以及现有方法在时间-尺度建模能力不足、依赖手工时频变换且模型复杂不利于边缘部署的局限,提出了一种融合多尺度动态注意力与1D-2D卷积结构的轻量级端到端故障诊断模型(Mu... 针对旋转机械声学信号中存在的非平稳性强与噪声干扰显著等问题,以及现有方法在时间-尺度建模能力不足、依赖手工时频变换且模型复杂不利于边缘部署的局限,提出了一种融合多尺度动态注意力与1D-2D卷积结构的轻量级端到端故障诊断模型(Multiscale Dynamic Attention and 1D-2D convolutional Fusion Network,MDAF-Net)。该模型集成4项关键模块:首先,构建多尺度动态加权特征提取(Multiscale Dynamic Weighting Feature Extractor,MDW-FE)模块,结合多尺度卷积核与自适应加权机制,以增强对非平稳声学特征的感知能力;其次,设计多尺度映射层(Reshaped Multiscale Projection,RMP),实现一维序列向二维结构的转换,保留时间-尺度关联信息;然后,引入融合深度可分卷积的金字塔注意力机制(Pyramid Convolutional Block Attention Module integrated with Depthwise Separable Convolution,P-CBAM-DSC),提升模型对故障区域的聚焦能力与上下文表达能力;最终,通过全局特征聚合分类器(Global Feature Aggregation Classifier,GFA-C)实现高效的端到端故障识别。在DCASE2023公开声音数据集与自建滚动轴承声纹平台上的实验结果表明,所提方法在准确率、模型轻量化与推理效率方面均优于主流轻量模型,展现出良好的诊断性能、噪声鲁棒性与边缘部署适应性。 展开更多
关键词 旋转机械 故障诊断 声学信号 轻量化网络 1d-2d卷积建模 多尺度动态注意力
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基于R(2+1)D时空特征融合与注意力的行为识别方法
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作者 李林玉 陈淑荣 《计算机应用与软件》 北大核心 2026年第2期248-254,共7页
针对3D卷积在人体行为识别任务中,连续视频帧图像的时空信息提取不足且跨通道交互信息关注度不够,导致识别准确率不高的问题,提出一种基于R(2+1)D网络的多分路时空信息融合与注意力的行为识别方法。提取视频帧图像进行数据增强;以R(2+1)... 针对3D卷积在人体行为识别任务中,连续视频帧图像的时空信息提取不足且跨通道交互信息关注度不够,导致识别准确率不高的问题,提出一种基于R(2+1)D网络的多分路时空信息融合与注意力的行为识别方法。提取视频帧图像进行数据增强;以R(2+1)D网络为基础框架并融入Inception思想,对输入的视频帧图像进行多路时空特征卷积并融合,利用ECA通道注意力对融合特征筛选跨通道交互信息,以提取更抽象的高层特征;进行分类,输出人体行为识别结果。该方法充分利用视频的时空特征和跨通道交互信息,在UCF101数据集上准确率达到94.71%,比基础R(2+1)D网络提高4.53百分点;且模型参数由原来的33.3×106减小为26.9×10^(6)。实验表明,该方法能有效提高人体行为识别的准确率。 展开更多
关键词 R(2+1)d 时空卷积 特征融合 高效通道注意力 跨通道交互
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异柠檬酸脱氢酶1突变介导D-2-羟基戊二酸代谢重编程在肿瘤免疫调控中的作用及相关药物研发进展
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作者 杨全军 柏丁源 +2 位作者 周雨萱 白露 郭澄 《上海交通大学学报(医学版)》 北大核心 2025年第9期1239-1248,共10页
异柠檬酸脱氢酶1(isocitrate dehydrogenase 1,IDH1)突变可异常产生致癌代谢物D-2-羟基戊二酸(D-2-hydroxyglutarate,D2HG),进而重塑肿瘤免疫微环境,近年来已成为肿瘤代谢-免疫交互研究的关键靶点。D2HG通过竞争性抑制内源性α-酮戊二... 异柠檬酸脱氢酶1(isocitrate dehydrogenase 1,IDH1)突变可异常产生致癌代谢物D-2-羟基戊二酸(D-2-hydroxyglutarate,D2HG),进而重塑肿瘤免疫微环境,近年来已成为肿瘤代谢-免疫交互研究的关键靶点。D2HG通过竞争性抑制内源性α-酮戊二酸依赖性双加氧酶,引发DNA组蛋白过甲基化与细胞分化阻滞,从而促进肿瘤的发生、发展、转移,并促使肿瘤产生耐药性。同时,D2HG抑制T细胞功能,促进髓系细胞扩增以及巨噬细胞极化,削弱免疫监视能力,形成免疫抑制状态,对免疫治疗响应产生影响。在胶质瘤、急性髓系白血病、胆管癌等多种肿瘤中,IDH1呈现出异质性和不同的预后特征。目前,针对IDH1突变的小分子抑制剂,如艾伏尼布(ivosidenib)、沃拉西尼布(vorasidenib)等,能够通过降低D2HG水平,部分逆转免疫抑制,在临床试验中显示出一定的疗效。然而,这些抑制剂存在疗效差异、耐药性及安全性等问题。IDH1抑制剂联合治疗旨在协同逆转代谢-表观遗传-免疫三重抑制网络,增强抗肿瘤药理效应,因而受到广泛关注。该文综述了IDH1突变介导D2HG代谢的肿瘤免疫调控网络,并全面综述了相关药物研发进展,希冀为肿瘤防治提供参考和思路。 展开更多
关键词 异柠檬酸脱氢酶1(IdH1) d-2-羟基戊二酸(d2HG) 免疫调控 艾伏尼布 沃拉西尼布 代谢重编程
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Simulation of the Hydrodynamic Functioning of the Cavally River Using a Coupled 1D-2D Model in the Ity Area (Zouan-Hounien in Côte d’Ivoire)
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作者 Affoué Berthe Yao Kouao Armand Anoh +2 位作者 Loukou Alexis Brou Menouan Wilfried Goli Lazare Kouakou Kouassi 《Open Journal of Modern Hydrology》 2021年第4期75-84,共10页
In recent years, the Cavally River has been subject to multiple activities, <span style="font-family:;" "="">including the construction of diversion channels and a bridge that makes it v... In recent years, the Cavally River has been subject to multiple activities, <span style="font-family:;" "="">including the construction of diversion channels and a bridge that makes it vulnerable to flooding. In order to assess the impact of these hydraulic structures on the <span>river hydrodynamic functioning, a 1D-2D model was realized. The</span> implementation of the 1D-2D model consisted </span><span style="font-family:;" "="">of </span><span style="font-family:;" "="">first </span><span style="font-family:;" "="">running</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">the 1D model, then the 2D model, and finally in coupling them. The 1D-2D model was designed with <span>the 1988 flood hydrograph, a Manning’s coefficient of 0.052 m<sup>1/3</sup>/s for the </span>minor bed and 0.06 m<sup>1/3</sup>/s for the major bed. The results of the hydraulic model show that the velocities are almost identical to those of the Cavally in natural operation. The values of the velocities are included between 0.4 m/s and 1.3 m/s at the level of the minor bed of the river and between 0.06 m/s and 0.71 m/s at the level of the floodplains. The average water level for flood propagation is 262.37 ± 0.44 m before construction of the structures and 262.23 ± <span>0.85 m after construction of the structures. The 0.41 m reduction in water</span> level due to the diversion canal and bridge is negligible compared to the total fluctuations of the Cavally River, which vary from 6 to 7 m over the year.</span> 展开更多
关键词 Ity Mines 1d-2d modeling FLOOdING Cavally River Côte d’Ivoire
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(4d+1)-正则图中的2d-因子 被引量:1
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作者 龙和平 《山东大学学报(理学版)》 CAS CSCD 北大核心 2002年第4期295-297,共3页
设d是一个正整数 ,G是一个 (4d +1 ) -正则图 .证明了若图G不含d +4条割边 ,则G有2d 因子 .进而说明上述结果是最好的 .
关键词 (4d+1)-正则图 2d-因子 割边 顶点集 边集 k-正则支撑子图 连通分支 无环图
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A deterministic distributed modeling approach of Mediterranean water-cycle assessment,application in the Var catchment,France
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作者 Siyuan Chang Zhengmiao Li +2 位作者 Xinyi Lian Philippe Gourbesville Qiang Ma 《River》 2025年第3期297-310,共14页
Characterized by special morphologic,geographic,hydrologic,and societal behaviors,the water resources management of the Mediterranean catchment often shows a higher level of complexity including security issues of wat... Characterized by special morphologic,geographic,hydrologic,and societal behaviors,the water resources management of the Mediterranean catchment often shows a higher level of complexity including security issues of water supply,inundation risks,and environment management under the perspective of climate change.To have a comprehensive understanding of the Mediterranean water-cycle system,a deterministic distributed hydrologic modeling approach has been developed and presented in this study based on an application in the Var catchment(2800 km^(2))located at the French Mediterranean region.A 1D and 2D coupled model of MIKE SHE and MIKE 11 has been set up under a series of hypotheses to represent the whole hydrologic and hydrodynamic processes including rainfall-runoff,snow-melting,channel flow,overland flow,and the water exchange between land surface and unsaturated/saturated zones.The developed model was first calibrated with 4 years daily records from 2008 to 2011,then to be validated and further run within hourly time interval to produce detailed representation of the catchment water-cycle from 2012 to 2014.The deterministic distributed modeling approach presented in this study is able to represent its complicated water-cycle and used for supporting the decision‐making process of the water resources management of the catchment. 展开更多
关键词 1d/2d coupled model distributed hydrological model flood management Mediterranean catchment
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Multidimensional data-driven porous media reconstruction:Inversion from 1D/2D pore parameters to 3D real pores
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作者 Peng Chi Jian-Meng Sun +5 位作者 Ran Zhang Wei-Chao Yan Huai-Min Dong Li-Kai Cui Rui-Kang Cui Xin Luo 《Petroleum Science》 2025年第7期2777-2793,共17页
Subsurface rocks,as complex porous media,exhibit multiscale pore structures and intricate physical properties.Digital rock physics technology has become increasingly influential in the study of subsurface rock propert... Subsurface rocks,as complex porous media,exhibit multiscale pore structures and intricate physical properties.Digital rock physics technology has become increasingly influential in the study of subsurface rock properties.Given the multiscale characteristics of rock pore structures,direct three-dimensional imaging at sub-micrometer and nanometer scales is typically infeasible.This study introduces a method for reconstructing porous media using multidimensional data,which combines one-dimensional pore structure parameters with two-dimensional images to reconstruct three-dimensional models.The pore network model(PNM)is stochastically reconstructed using one-dimensional parameters,and a generative adversarial network(GAN)is utilized to equip the PNM with pore morphologies derived from two-dimensional images.The digital rocks generated by this method possess excellent controllability.Using Berea sandstone and Grosmont carbonate samples,we performed digital rock reconstructions based on PNM extracted by the maximum ball algorithm and compared them with stochastically reconstructed PNM.Pore structure parameters,permeability,and formation factors were calculated.The results show that the generated samples exhibit good consistency with real samples in terms of pore morphology,pore structure,and physical properties.Furthermore,our method effectively supplements the micropores not captured in CT images,demonstrating its potential in multiscale carbonate samples.Thus,the proposed reconstruction method is promising for advancing porous media property research. 展开更多
关键词 3d digital rock Pore network model 1d/2d pore parameters Pore structure Generative adversarial network
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Fine-scale damage assessment of urban flooding based on the 1D/2D coupled hydrodynamic model 被引量:1
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作者 Boliang Dong Junqiang Xia +1 位作者 Qijie Li Xiaojie Wang 《River》 2023年第4期403-420,共18页
Due to the high population density and economic property in urban environments,urban flooding can result in substantial economic losses.However,accurate urban flood modeling and assessing the associated damages are ch... Due to the high population density and economic property in urban environments,urban flooding can result in substantial economic losses.However,accurate urban flood modeling and assessing the associated damages are challenging due to complex urban layouts and rugged topography.Furthermore,the rapid development of urban underground spaces has introduced additional complexities.To address the demanding need for accurate flood modeling and damage assessment in cities,a fine-scale flood damage assessment method was proposed in this study,based on the 1D/2D coupled hydrodynamic model,which can not only assess the flood damage on the ground surface but also evaluate the flood loss in underground spaces.Taking the Gangxi drainage area in Wuhan City,China as a case,this study extensively discussed the flood inundation processes on the ground surface as well as in the buildings and underground spaces,under different rainfall scenarios with the return period ranging from 2 to 200 years.Based on the high spatial-temporal hydrodynamic simulations,the flood damage degrees were evaluated for the buildings and underground spaces with different industry types.The results indicated that the inundation of buildings and underground spaces in densely built cities cannot be neglected in urban flood modeling.Buildings with public service attributes can have a higher flood damage degree,as compared with other types of buildings and underground spaces. 展开更多
关键词 1d/2d coupled modeling flood damage assessment underground spaces urban flooding
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An Implicit Coupled 1D/2D Model for Unsteady Subcritical Flow in Channel Networks and Embayment
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作者 GENG Yan-fen WANG Zhi-li 《China Ocean Engineering》 SCIE EI CSCD 2020年第1期110-118,共9页
In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method a... In this study, 1D and 2D shallow-water models were coupled to simulate unsteady flow in channel networks and embayment. The 1D model solved the 1D shallow-water equations (St. Venant) using the Preissmann box method and targeted long narrow reaches of the river networks, while the 2D model targeted broad channels and embayment and solved the 2D shallow-water equations using a semi-implicit scheme applied to an unstructured grid of triangular cells. The 1D and 2D models were solved simultaneously by building a matrix for the free surface elevation at every 1D junction and 2D cell center. Velocities were then computed explicitly based on the results at the previous time step and the updated water level. The originality of the scheme arose from a novel coupling method. The results showed that the coupled 1D/2D model produced identical results as the full 2D model in classical to benchmark problems with considerable savings in computational effort. Application of the model to the Pearl River Estuary in southern China showed that complex patterns of tidal wave propagation could be efficiently modeled. 展开更多
关键词 1d river network model 2d unstructured model full coupling model Pearl River delta
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轻量级(2+1)D卷积结构的动态手势识别研究 被引量:4
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作者 赵康 黎向锋 +1 位作者 李高扬 左敦稳 《微电子学与计算机》 2022年第9期46-54,共9页
目前,基于卷积神经网络的动态手势识别方法取得了巨大的进展,但神经网络模型具有很大的参数量,计算成本和内存占用较大,很难应用在设备资源有限的场合.以减少计算量和参数量为出发点,提出了一种轻量级(2+1)D卷积结构.该结构在(2+1)D卷... 目前,基于卷积神经网络的动态手势识别方法取得了巨大的进展,但神经网络模型具有很大的参数量,计算成本和内存占用较大,很难应用在设备资源有限的场合.以减少计算量和参数量为出发点,提出了一种轻量级(2+1)D卷积结构.该结构在(2+1)D卷积结构的基础上,将其中的3D卷积替换为3D深度可分离卷积,在输出向量维度不变的前提下,进一步减少了(2+1)D卷积结构的计算量和参数量.为了弥补时空特征在表征动态手势上的不足,融合注意力机制模块,专注于对运动特征的提取,结合轻量级(2+1)D卷积结构提取的时空特征,可以更好地表征手势动作.实验结果表明,注意力机制模块的插入,在不增加太多额外计算和空间成本的前提下,进一步提高了模型的识别精度.基于以上结构构建的模型,在20BN-jester、EgoGesture和IsoGD数据集上分别取得了96.62%、91.83%和60.1%的识别精度,模型参数量和浮点计算量分别为5.05M和12.81GFLOPs,相比于其他手势识别模型,计算成本和内存占用大大减少,实时手势识别速度达到每秒70帧. 展开更多
关键词 动态手势识别 卷积神经网络 轻量级(2+1)d卷积结构 注意力机制
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(2+1)D多时空信息融合模型及在行为识别的应用 被引量:3
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作者 谈咏东 王永雄 +1 位作者 陈姝意 缪银龙 《信息与控制》 CSCD 北大核心 2019年第6期715-722,共8页
针对常规的卷积神经网络时空感受野尺度单一,难以提取视频中多变的时空信息的问题,利用(2+1)D模型将时间信息和空间信息在一定程度上解耦的特性,提出了(2+1)D多时空信息融合的卷积残差神经网络,并用于人体行为识别.该模型以3×3空... 针对常规的卷积神经网络时空感受野尺度单一,难以提取视频中多变的时空信息的问题,利用(2+1)D模型将时间信息和空间信息在一定程度上解耦的特性,提出了(2+1)D多时空信息融合的卷积残差神经网络,并用于人体行为识别.该模型以3×3空间感受野为主,1×1空间感受野为辅,与3种不同时域感受野交叉组合构建了6种不同尺度的时空感受野.提出的多时空感受野融合模型能够同时获取不同尺度的时空信息,提取更丰富的人体行为特征,因此能够更有效识别不同时间周期、不同动作幅度的人体行为.另外提出了一种视频时序扩充方法,该方法能够同时在空间信息和时间序列扩充视频数据集,丰富训练样本.提出的方法在公共视频人体行为数据集UCF101和HMDB51上子视频的识别率超过或接近最新的视频行为识别方法. 展开更多
关键词 时空信息融合 人体行为识别 (2+1)d卷积残差神经网络 感受野 卷积神经网络
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甘油与氯化钠模型热反应中生成3-氯-1,2-丙二醇的研究 被引量:5
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作者 张岱 孙培培 +2 位作者 黄明泉 孙宝国 邹青青 《食品工业科技》 CAS CSCD 北大核心 2013年第9期74-78,共5页
以甘油、氯化钠、水为原料建立热反应模型,结合气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)分析,对其生成的3-氯-1,2-丙二醇(3-MCPD)进行了研究。通过正交实验,考察了反应时间、温度和各原料用量对3-MCPD生成量的影响... 以甘油、氯化钠、水为原料建立热反应模型,结合气相色谱-质谱法(gas chromatography-mass spectrometry,GC-MS)分析,对其生成的3-氯-1,2-丙二醇(3-MCPD)进行了研究。通过正交实验,考察了反应时间、温度和各原料用量对3-MCPD生成量的影响,同时研究了在热反应模型中分别加入不同种类单糖和氨基酸后3-MCPD生成量的变化规律,并对其反应机理进行了探讨。结果表明,反应时间2h、反应温度140℃、甘油用量0.05g(占原料总量0.31%)、NaCl用量1.0g(6.23%)、水用量15g(93.46%),3-MCPD生成量最少;葡萄糖、果糖、木糖、甘露糖、半乳糖、缬氨酸、精氨酸、赖氨酸、丝氨酸、亮氨酸、苯丙氨酸、苏氨酸、组氨酸使3-MCPD的生成量减少;谷氨酸、蛋氨酸、丙氨酸、天冬氨酸、甘氨酸使3-MCPD的生成量增加;半胱氨酸、酪氨酸、脯氨酸、色氨酸对3-MCPD的生成无明显作用。 展开更多
关键词 模型热反应 甘油 3-氯-1 2-丙二醇(3-MCPd) 单糖 氨基酸
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Mathematical model for flood routing in Jingjiang River and Dongting Lake network 被引量:6
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作者 Zuo-tao XIE Fang-li YANG Xiao-li FU 《Water Science and Engineering》 EI CAS 2012年第3期259-268,共10页
The main stream of the Yangtze River, Dongting Lake, and the river network in the Jingjiang reach of the Yangtze River constitute a complex water system. This paper develops a one-dimensional (l-D) mathematical mode... The main stream of the Yangtze River, Dongting Lake, and the river network in the Jingjiang reach of the Yangtze River constitute a complex water system. This paper develops a one-dimensional (l-D) mathematical model for flood routing in the river network Of the Jingjiang River and Dongting Lake using the explicit finite volume method. Based on observed data during the flood periods in 1996 and 1998, the model was calibrated and validated, and the results show that the model is effective and has high accuracy. In addition, the one-dimensional mathematical model for the river network and the horizontal two-dimensional (2-D) mathematical model for the Jingjiang flood diversion area were coupled to simulate the flood process in the Jingjiang River, Dongting Lake, and the Jingjiang flood diversion area. The calculated results of the coupled model are consistent with the practical processes. Meanwhile, the results show that the flood diversion has significant effects on the decrease of the peak water level at the Shashi and Chenjiawan hydrological stations near the flood diversion gates, and the effect is more obvious in the downstream than in the upstream. 展开更多
关键词 Jingjiang River dongting Lake Jing/iang flood diversion area flood routing rivernetworks 1-d and 2-d coupled model
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Applying Deep Learning Models to Mouse Behavior Recognition
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作者 Ngoc Giang Nguyen Dau Phan +7 位作者 Favorisen Rosyking Lumbanraja Mohammad Reza Faisal Bahriddin Abapihi Bedy Purnama Mera Kartika Delimayanti Kunti Robiatul Mahmudah Mamoru Kubo Kenji Satou 《Journal of Biomedical Science and Engineering》 2019年第2期183-196,共14页
In many animal-related studies, a high-performance animal behavior recognition system can help researchers reduce or get rid of the limitation of human assessments and make the experiments easier to reproduce. Recentl... In many animal-related studies, a high-performance animal behavior recognition system can help researchers reduce or get rid of the limitation of human assessments and make the experiments easier to reproduce. Recently, although deep learning models are holding state-of-the-art performances in human action recognition tasks, these models are not well-studied in applying to animal behavior recognition tasks. One reason is the lack of extensive datasets which are required to train these deep models for good performances. In this research, we investigated two current state-of-the-art deep learning models in human action recognition tasks, the I3D model and the R(2 + 1)D model, in solving a mouse behavior recognition task. We compared their performances with other models from previous researches and the results showed that the deep learning models that pre-trained using human action datasets then fine-tuned using the mouse behavior dataset can outperform other models from previous researches. It also shows promises of applying these deep learning models to other animal behavior recognition tasks without any significant modification in the models’ architecture, all we need to do is collecting proper datasets for the tasks and fine-tuning the pre-trained models using the collected data. 展开更多
关键词 MOUSE BEHAVIOR RECOGNITION dEEP Learning I3d modelS R(2 + 1)d modelS
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基于一维心电二维特征提取的情绪识别研究
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作者 尉思懿 安宇坤 +2 位作者 陈佳雪 陈开 周平 《中国医疗器械杂志》 2026年第1期1-6,共6页
客观的情绪识别在生理健康、医疗与教育等领域均有着重要的研究意义。从信号获取难易程度、成本与使用者接受度等角度来看,人体的心电信号是实现客观情绪识别的重要生物标志物。针对深度学习网络在一维心电信号时-空特征提取、融合方面... 客观的情绪识别在生理健康、医疗与教育等领域均有着重要的研究意义。从信号获取难易程度、成本与使用者接受度等角度来看,人体的心电信号是实现客观情绪识别的重要生物标志物。针对深度学习网络在一维心电信号时-空特征提取、融合方面的难点,该文首先提出了一种基于小波包分解的1D-2D信号转换方法,将一维心电信号转换为“二维图像”;随后,以此“二维图像”作为输入,以ResNet18作为骨干网,设计了Fusion Block模块,提高了网络的时-空特征提取、融合能力。该文在WESAD与SWELL-KW数据集上进行了情绪识别任务,实验结果表明,与次优方法相比,该文提出的情绪识别方法在准确度与F1分数两个指标上分别高出2.19%与4.48%,为情绪的客观识别提供了技术支持。 展开更多
关键词 情绪识别 1d-2d信号转换 小波包分解 深度学习
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Integrating 1D and 2D hydrodynamic,sediment transport model for dam-break flow using finite volume method 被引量:3
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作者 ZHANG MingLiang XU YuanYuan +1 位作者 HAO ZiNing QIAO Yang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第4期774-783,共10页
The purpose of this study is to set up a dynamically linked 1D and 2D hydrodynamic and sediment transport models for dam break flow.The 1D-2D coupling model solves the generalized shallow water equations,the non-equil... The purpose of this study is to set up a dynamically linked 1D and 2D hydrodynamic and sediment transport models for dam break flow.The 1D-2D coupling model solves the generalized shallow water equations,the non-equilibrium sediment transport and bed change equations in a coupled fashion using an explicit finite volume method.It considers interactions among transient flow,strong sediment transport and rapid bed change by including bed change and variable flow density in the flow continuity and momentum equations.An unstructured Quadtree rectangular grid with local refinement is used in the 2D model.The intercell flux is computed by the HLL approximate Riemann solver with shock captured capability for computing the dry-to-wet interface for all models.The effects of pressure and gravity are included in source term in this coupling model which can simplify the computation and eliminate numerical imbalance between source and flux terms.The developed model has been tested against experimental and real-life case of dam-break flow over fix bed and movable bed.The results are compared with analytical solution and measured data with good agreement.The simulation results demonstrate that the coupling model is capable of calculating the flow,erosion and deposition for dam break flows in complicated natural domains. 展开更多
关键词 1d/2d coupling model finite volume method HLL approximate Riemann solver non-equilibrium sediment transport
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A COUPLED 1-D AND 2-D CHANNEL NETWORK MATHEMATICAL MODEL USED FOR FLOW CALCULATIONS IN THE MIDDLE REACHES OF THE YANGTZE RIVER 被引量:5
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作者 HAN Dong FANG Hong-wei BAIJing HE Guo-jian 《Journal of Hydrodynamics》 SCIE EI CSCD 2011年第4期521-526,共6页
A coupled one-dimensional (1-D) and two-dimensional (2-D) channel network mathematical model is proposed for flow calculations at nodes in a channel network system in this article. For the 1-D model, the finite di... A coupled one-dimensional (1-D) and two-dimensional (2-D) channel network mathematical model is proposed for flow calculations at nodes in a channel network system in this article. For the 1-D model, the finite difference method is used to discretize the Saint-Venant equations in all channels of a looped network. The Alternating Direction Implicit (ADI) method is adopted for the 2-D model at the nodes. In the coupled model, the 1-D model provides a good approximation with small computational effort, while the 2-D model is applied for complex topography to achieve a high accuracy. An Artificial Neural Network (ANN.) method is used for the data exchange and the connectivity between the 1-D and 2-D models. The coupled model is applied to the Jingjiang-Dongting Lake region, to simulate the tremendous looped channel network system, and the results are compared with field data. The good agreement shows that the coupled hydraulic model is more effective than the conventional 1-D model. 展开更多
关键词 Coupled 1-d and 2-d model looped channel network system Alternating driection Implicit (AdI) Jingjiang-dongting Lake region
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The adjustment of γ-aminobutyric acid_A tonic subunits in Huntington's disease:from transcription to translation to synaptic levels into the neostriatum
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作者 Abraham Rosas-Arellano Argel Estrada-Mondragón +2 位作者 Carola A.Mantellero Carlos Tejeda-Guzmán Maite A.Castro 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第4期584-590,共7页
γ-Aminobutyric acid(GABA),plays a key role in all stages of life,also is considered the main inhibitory neurotransmitter.GABA activates two kind of membrane receptors known as GABAA and GABAB,the first one is respo... γ-Aminobutyric acid(GABA),plays a key role in all stages of life,also is considered the main inhibitory neurotransmitter.GABA activates two kind of membrane receptors known as GABAA and GABAB,the first one is responsible to render tonic inhibition by pentameric receptors containing α4-6,β3,δ,or ρ1-3 subunits,they are located at perisynaptic and/or in extrasynaptic regions.The biophysical properties of GABAA tonic inhibition have been related with cellular protection against excitotoxic injury and cell death in presence of excessive excitation.On this basis,GABAA tonic inhibition has been proposed as a potential target for therapeutic intervention of Huntington's disease.Huntington's disease is a neurodegenerative disorder caused by a genetic mutation of the huntingtin protein.For experimental studies of Huntington's disease mouse models have been developed,such as R6/1,R6/2,Hdh Q92,Hdh Q150,as well as YAC128.In all of them,some key experimental reports are focused on neostriatum.The neostriatum is considered as the most important connection between cerebral cortex and basal ganglia structures,its cytology display two pathways called direct and indirect constituted by medium sized spiny neurons expressing dopamine D1 and D2 receptors respectively,they display strong expression of many types of GABAA receptors,including tonic subunits.The studies about of GABAA tonic subunits and Huntington's disease into the neostriatum are rising in recent years,suggesting interesting changes in their expression and localization which can be used as a strategy to delay the cellular damage caused by the imbalance between excitation and inhibition,a hallmark of Huntington's disease. 展开更多
关键词 GABAA extrasynaptic and perisynaptic y-aminobutyric acidA receptors STRIATUM R6/1 R6/2 HdhQ92 HdhQ111 HdhQ150 N171-82Q and YAC128 Hd transgenics mice models CHOREA mutanthuntingtin inhibitory neurotransmission d1 medium sized spiny neurons d2 medium sized spiny neurons
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17aα—D-高炔雌二醇-3-乙酯联合γ射线照射对不同品系小鼠的抑瘤作用 被引量:5
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作者 王月英 王小春 +8 位作者 吴红英 李德冠 张恒 宋娜玲 褚丽萍 路璐 杜丽清 王彦 孟爱民 《国际放射医学核医学杂志》 2012年第2期97-100,共4页
目的对比观察17a α—D-高炔雌二醇-3-乙酯(DHEA)对不同品系小鼠肺腺癌的抑瘤作用及探讨合用^137Cs γ射线照射是否具有抑瘤增效作用。方法将LA795肺腺癌细胞用生理盐水稀释为浓度约3.5×10^7/ml瘤细胞,接种于近交系IRM-1和IR... 目的对比观察17a α—D-高炔雌二醇-3-乙酯(DHEA)对不同品系小鼠肺腺癌的抑瘤作用及探讨合用^137Cs γ射线照射是否具有抑瘤增效作用。方法将LA795肺腺癌细胞用生理盐水稀释为浓度约3.5×10^7/ml瘤细胞,接种于近交系IRM-1和IRM-2小鼠腋下,0.2ml/只,24h后分别将IRM-1和IRM-2荷瘤小鼠随机分为8组:对照组、单照组、DHEA(低、中、高剂量)组和DHEA(低、中、高剂量)联合照射组。DHEA组与DHEA联合照射组采取腹腔给药,每日1次,连续7d。其中,DHEA联合照射组于给药的第4日进行全身1Gy照射,每日1次,连续5d。观察DHEA联合γ射线照射对小鼠肺腺癌的抑瘤效果及对相关免疫学指标的影响。结果DHEA低、中、高剂量组对IRM-1荷瘤小鼠的抑瘤率分别为38.05%、49.33%和48.18%,与对照组比较差异有统计学意义(担3.417,4.929和4.889,P均〈0.01),联合^137Cs γ射线照射后的抑瘤率分别为56.98%、64.44%和62.72%,与对照组比较差异有统计学意义(t=5.475,5.770和6.165,P均〈0.01)。DHEA低、中、高剂量组对IRM-2小鼠的抑瘤率分别为42.73%、70.91%和67.73%,其中,中、高剂量组与对照组比较差异有统计学意义(t=3.239和3.062,P均〈0.01),联合^137Cs γ射线照射后的抑瘤率分别为63.63%、75.00%和68.64%,与对照组比较差异有统计学意义(t=2.834,3.426和3.156,P分别为〈0.05,〈0.01和〈0.01)。结论DHEA对不同品系小鼠肺腺癌细胞均有抑制作用,联合γ射线照射后的抑瘤疗效比单纯DHEA组更为明显。 展开更多
关键词 Γ射线 肺肿瘤 17a dd-高炔雌二醇-3-乙酯 IRM-1小鼠 IRM-2小鼠
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融合注意力机制的驾驶人行为识别模型研究
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作者 徐慧智 张原铭 《重庆理工大学学报(自然科学)》 北大核心 2025年第10期1-12,共12页
选取辅助驾驶中驾驶人行为识别作为研究对象,设计基于融合时间和通道注意力机制的功能模块,构建驾驶人行为识别模型,提升识别准确率。探究多角度数据对模型性能提升情况,自建多视角驾驶人行为数据集,包括4种拍摄视角、10种驾驶行为、114... 选取辅助驾驶中驾驶人行为识别作为研究对象,设计基于融合时间和通道注意力机制的功能模块,构建驾驶人行为识别模型,提升识别准确率。探究多角度数据对模型性能提升情况,自建多视角驾驶人行为数据集,包括4种拍摄视角、10种驾驶行为、1148个视频数据。构建TCAM-R(2+1)D驾驶人行为识别模型,以(2+1)D卷积模块为基础,结合ResNET主干网络,提出融合时间和通道注意力机制的功能模块,增强模型提取时序信息的能力。使用Adabound优化器训练模型,提高模型的识别准确率和泛化能力。实验结果表明:通过增加模型的注意力机制,相较于R(2+1)D模型,自建数据集驾驶人行为识别准确率提高3.03%。采用大型人体运动数据集(HMBD51)进行消融实验,增加融合注意力机制功能模块准确率至59.60%(提高了1.93%),验证融合时间和通道注意力机制的增益效能。 展开更多
关键词 深度学习 行为识别 注意力机制 R(2+1)d模型
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