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试论边缘曲式在幻想曲体裁中的实践
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作者 陈馨婷 《贵州大学学报(艺术版)》 2006年第1期42-45,49,共5页
幻想曲是以相对自由灵活的结构,不固定的外在形式及充分发挥创作才能和想象,贴近作品具体内容为特征的。在实际创作中,幻想曲作品的具体结构往往同时包含多个结构原则的共同作用,有时则包含对某些结构原则的刻意违悖。可以说采取的是一... 幻想曲是以相对自由灵活的结构,不固定的外在形式及充分发挥创作才能和想象,贴近作品具体内容为特征的。在实际创作中,幻想曲作品的具体结构往往同时包含多个结构原则的共同作用,有时则包含对某些结构原则的刻意违悖。可以说采取的是一些“边缘”性的曲式。探索边缘性曲式在幻想曲作品中的实践,使我们得以接近作曲家们处理内容与形式之间,典型与具体之间的矛盾和发展乐思,施展创作才能的真相,同时也期望通过这种探索为进一步理解幻想曲作品及边缘曲式结构提供依据和帮助。 展开更多
关键词 边缘曲式 幻想曲 三部性结构原则 回旋性原则 奏鸣性原则
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鄂尔多斯盆地西缘上奥陶统拉什仲组包卷层理成因机制探讨
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作者 李向东 陈洪达 +1 位作者 陈海燕 魏泽昳 《古地理学报》 CAS CSCD 北大核心 2022年第6期1130-1148,共19页
包卷层理是软沉积物变形构造的一种重要类型,其成因较为复杂。在深水沉积环境中,探讨内波、内潮汐作用与包卷层理成因之间的关系,对于丰富包卷层理形成机制和完善内波、内潮汐沉积鉴别标志均具有重要意义。鄂尔多斯盆地西缘北部内蒙古... 包卷层理是软沉积物变形构造的一种重要类型,其成因较为复杂。在深水沉积环境中,探讨内波、内潮汐作用与包卷层理成因之间的关系,对于丰富包卷层理形成机制和完善内波、内潮汐沉积鉴别标志均具有重要意义。鄂尔多斯盆地西缘北部内蒙古桌子山地区上奥陶统拉什仲组阻塞浊流沉积中发育的包卷层理,依据形态可分为倾向型规则包卷层理和回旋状包卷层理2类:前者具有紧闭背形、开阔向形及背形之下发育砂核等特征,常和双向交错层理伴生;后者属于层内扭曲变形,多限定在具有削截现象的层系内,常和复合流沉积构造及浪成波纹层理伴生。综合沉积特征、包卷层理特征、伴生沉积构造及相关研究成果可推测:倾向型规则包卷层理主要由内潮汐形成,在液化过程中出现明显的密度倒置,因瑞利—泰勒不稳定引起变形,在流体持续剪切作用下进一步改造形成;回旋状包卷层理主要由短周期内波形成,包括浊流反射形成的随机内波和内潮汐裂解形成的内孤立波,表现为同沉积分层液化,但一般不出现密度倒置现象,因开尔文—亥姆霍兹不稳定引起变形,流体剪切也有一定的改造作用。 展开更多
关键词 包卷层理 内波内潮汐 沉积构造 上奥陶统 鄂尔多斯盆地
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印度尼西亚苏拉威西岛—北马露姑群岛区域地质构造背景及其对蛇绿岩、红土型镍矿规模的控制 被引量:1
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作者 杨明德 杨玉华 《矿产与地质》 2015年第6期722-725,739,共5页
三大巨形板块碰撞汇聚带控制了班达海左行旋卷构造带,地幔对流、推-拉模式驱动板块运动,形成左行平移断裂,诱发本区海陆构造格局。早期引张软流圈地幔超基性岩浆沿洋中脊上拱,晚期挤压推覆到火山岛弧边缘部位。蛇绿岩沿两个"K"... 三大巨形板块碰撞汇聚带控制了班达海左行旋卷构造带,地幔对流、推-拉模式驱动板块运动,形成左行平移断裂,诱发本区海陆构造格局。早期引张软流圈地幔超基性岩浆沿洋中脊上拱,晚期挤压推覆到火山岛弧边缘部位。蛇绿岩沿两个"K"字形岛展布,不同的构造尺度控制了蛇绿岩的时、空、类型、规模及红土型镍矿的分布,以白垩系蛇绿岩控制的红土型镍矿规模最大。 展开更多
关键词 苏拉威西 板块 旋卷构造 白垩系 蛇绿岩 矿床规模
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云南永宁P_1上部砾屑灰岩成因及意义探讨 被引量:1
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作者 刘亚伟 王多义 +5 位作者 鲁仁齐 邓美洲 武鹏 曾青高 刘亚杰 刘涛 《物探化探计算技术》 CAS CSCD 2007年第6期530-533,470,共4页
在云南省永宁地区,下二叠统(P1)上部砾屑灰岩被首次识别为重力流沉积,其重力流沉积可分为碎屑流沉积、滑塌(崩塌)沉积,以碎屑流沉积为主。通过沉积相、沉积物组份及物源分析,云南省永宁地区处于浅海斜坡断崖(陡坎)带,与华里西期伸展运... 在云南省永宁地区,下二叠统(P1)上部砾屑灰岩被首次识别为重力流沉积,其重力流沉积可分为碎屑流沉积、滑塌(崩塌)沉积,以碎屑流沉积为主。通过沉积相、沉积物组份及物源分析,云南省永宁地区处于浅海斜坡断崖(陡坎)带,与华里西期伸展运动有关。因此,讨论砾屑灰岩成因,对该区的古构造发展,以及对峨眉山地裂运动开始时间的研究,都具有重要意义。 展开更多
关键词 二叠系 砾屑灰岩 重力流沉积 逆粒序 包卷构造 同生断裂
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基于NEPTUNE3D开展的脉冲功率装置汇流区三维PIC数值模拟
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作者 赵海龙 董烨 +2 位作者 周海京 王刚华 王强 《强激光与粒子束》 EI CAS CSCD 北大核心 2020年第7期133-139,共7页
大型脉冲功率装置真空汇流区的电子输运过程对于电流汇聚有重要的影响,在高性能计算集群的帮助下,使用NEPTUNE3D软件开展三维全电磁PIC模拟进行了研究,模拟区域(34 cm×34 cm×18 cm)包括双层柱-孔盘旋(DPHC)结构和部分内、外... 大型脉冲功率装置真空汇流区的电子输运过程对于电流汇聚有重要的影响,在高性能计算集群的帮助下,使用NEPTUNE3D软件开展三维全电磁PIC模拟进行了研究,模拟区域(34 cm×34 cm×18 cm)包括双层柱-孔盘旋(DPHC)结构和部分内、外磁绝缘传输线等关键位置。计算结果清晰地展示了零磁位区分布和电子输运轨迹,电子主要由外磁绝缘传输线阴极表面发射,在洛伦兹力作用下向中心漂移并损失在零磁位区处;对电子能量沉积的统计结果表明,受电子流轰击最严重的位置在DPHC结构下层阳极柱表面,来自大型脉冲功率装置的实验结果证实了上述结论。根据计算结果,最大电流损失率(437 kA,27%)发生在电流传输的早期时刻(~15 ns),而电流峰值时刻损失率则仅有0.48%,此时磁绝缘已完全生效,表明DPHC结构在峰值电流的汇聚与传输上有很高的效率。 展开更多
关键词 脉冲功率装置 汇流区 PIC模拟 NEPTUNE3D
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继承与超越——《图画展览会》创作特征探索 被引量:1
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作者 陈馨婷 《贵州大学学报(艺术版)》 2004年第1期51-53,共3页
钢琴组曲《图画展览会》由穆索尔斯基创作并以拉威尔改编的管弦乐版本广泛流传于世。立足这部伟大作品产生的独特时代和人文背景 ,通过对《图画展览会》在曲式结构、调式调性、和声、主题旋律及管弦乐版本的配器等方面的一些创作特点进... 钢琴组曲《图画展览会》由穆索尔斯基创作并以拉威尔改编的管弦乐版本广泛流传于世。立足这部伟大作品产生的独特时代和人文背景 ,通过对《图画展览会》在曲式结构、调式调性、和声、主题旋律及管弦乐版本的配器等方面的一些创作特点进行分析 ,探索其对于古典作曲原则的“继承”与“超越” ,及对于后世音乐艺术发展所具有的特殊而深远的意义。 展开更多
关键词 回旋性结构原则 动力性再现 非方整性结构 收拢性收束 三部性结构原则 中古调式 逆分型节奏动机 功能性和声
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基于海上无人值守的靶载终端结构系统研究
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作者 王毅亮 郭凯 《遥测遥控》 2022年第5期11-21,共11页
针对海洋恶劣环境,研究了一种适用于无人值守的靶载终端结构系统。通过建立靶载终端散热数学模型得到上下插齿式最优散热结构,提出了一种基于高度差的双层回旋式密封结构及方法。分析了靶载终端呼吸效应的产生机理及解决措施,研制了抗... 针对海洋恶劣环境,研究了一种适用于无人值守的靶载终端结构系统。通过建立靶载终端散热数学模型得到上下插齿式最优散热结构,提出了一种基于高度差的双层回旋式密封结构及方法。分析了靶载终端呼吸效应的产生机理及解决措施,研制了抗随机波载及抗冲击能力的缓冲振动平台,并且通过密封及振动冲击试验验证了靶载终端结构系统的可行性和准确性。为恶劣海洋环境下无人值守的靶载终端提供有力的技术保障,提高我国武器靶载终端作战水平。 展开更多
关键词 无人值守 靶载终端 上下插齿式散热 双层回旋式密封结构 呼吸效应 缓冲振动平台
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Deep learning based classification of rock structure of tunnel face 被引量:20
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作者 Jiayao Chen Tongjun Yang +2 位作者 Dongming Zhang Hongwei Huang Yu Tian 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第1期395-404,共10页
The automated interpretation of rock structure can improve the efficiency,accuracy,and consistency of the geological risk assessment of tunnel face.Because of the high uncertainties in the geological images as a resul... The automated interpretation of rock structure can improve the efficiency,accuracy,and consistency of the geological risk assessment of tunnel face.Because of the high uncertainties in the geological images as a result of different regional rock types,as well as in-situ conditions(e.g.,temperature,humidity,and construction procedure),previous automated methods have limited performance in classification of rock structure of tunnel face during construction.This paper presents a framework for classifying multiple rock structures based on the geological images of tunnel face using convolutional neural networks(CNN),namely Inception-ResNet-V2(IRV2).A prototype recognition system is implemented to classify 5 types of rock structures including mosaic,granular,layered,block,and fragmentation structures.The proposed IRV2 network is trained by over 35,000 out of 42,400 images extracted from over 150 sections of tunnel faces and tested by the remaining 7400 images.Furthermore,different hyperparameters of the CNN model are introduced to optimize the most efficient algorithm parameter.Among all the discussed models,i.e.,ResNet-50,ResNet-101,and Inception-v4,Inception-ResNet-V2 exhibits the best performance in terms of various indicators,such as precision,recall,F-score,and testing time per image.Meanwhile,the model trained by a large database can obtain the object features more comprehensively,leading to higher accuracy.Compared with the original image classification method,the sub-image method is closer to the reality considering both the accuracy and the perspective of error divergence.The experimental results reveal that the proposed method is optimal and efficient for automated classification of rock structure using the geological images of the tunnel face. 展开更多
关键词 convolutional neural network Inception-ResNet-V2 Rock structure Image classification
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结合注意力机制的双流卷积自编码高光谱解混方法
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作者 苏晓通 郭宝峰 +2 位作者 尤靖云 吴文豪 许张弛 《激光与光电子学进展》 CSCD 北大核心 2024年第4期417-425,共9页
针对基于卷积自编码进行空-谱联合的高光谱解混方法中,过度引入像元光谱之间的空间相关性导致丰度过于平滑的现象,提出一种结合注意力机制的双流卷积自编码高光谱解混方法(DSCU-Net)。首先,利用双流卷积网络分别提取高光谱图像的空间特... 针对基于卷积自编码进行空-谱联合的高光谱解混方法中,过度引入像元光谱之间的空间相关性导致丰度过于平滑的现象,提出一种结合注意力机制的双流卷积自编码高光谱解混方法(DSCU-Net)。首先,利用双流卷积网络分别提取高光谱图像的空间特征和光谱特征;其次,为了确保空间特征和光谱特征之间的平衡性,引入通道注意力机制对提取到的空间特征进行重加权,并对光谱特征和重加权后的空间特征进行融合;最后,使用融合后的特征进行高光谱图像重构,并将重构结果送入解混网络的主干网络中进行光谱解混。通过最小化两次重构误差进行解混网络的训练。为了验证所提方法的性能,在两个真实数据集上进行实验,并对复杂场景下算法的性能表现进行分析。结果表明,DSCU-Net能够有效减少过度引入空间相关性造成丰度过于平滑的现象,具有更好的解混性能。 展开更多
关键词 遥感 高光谱解混 卷积自编码器 通道注意力机制 双流结构
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Graph Convolutional Networks Embedding Textual Structure Information for Relation Extraction
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作者 Chuyuan Wei Jinzhe Li +2 位作者 Zhiyuan Wang Shanshan Wan Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第5期3299-3314,共16页
Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,... Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,sentiment analysis and question-answering systems.However,previous studies ignored much unusedstructural information in sentences that could enhance the performance of the relation extraction task.Moreover,most existing dependency-based models utilize self-attention to distinguish the importance of context,whichhardly deals withmultiple-structure information.To efficiently leverage multiple structure information,this paperproposes a dynamic structure attention mechanism model based on textual structure information,which deeplyintegrates word embedding,named entity recognition labels,part of speech,dependency tree and dependency typeinto a graph convolutional network.Specifically,our model extracts text features of different structures from theinput sentence.Textual Structure information Graph Convolutional Networks employs the dynamic structureattention mechanism to learn multi-structure attention,effectively distinguishing important contextual features invarious structural information.In addition,multi-structure weights are carefully designed as amergingmechanismin the different structure attention to dynamically adjust the final attention.This paper combines these featuresand trains a graph convolutional network for relation extraction.We experiment on supervised relation extractiondatasets including SemEval 2010 Task 8,TACRED,TACREV,and Re-TACED,the result significantly outperformsthe previous. 展开更多
关键词 Relation extraction graph convolutional neural networks dependency tree dynamic structure attention
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Pixel-level crack segmentation of tunnel lining segments based on an encoder–decoder network
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作者 Shaokang HOU Zhigang OU +1 位作者 Yuequn HUANG Yaoru LIU 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2024年第5期681-698,共18页
Regular detection and repair for lining cracks are necessary to guarantee the safety and stability of tunnels.The development of computer vision has greatly promoted structural health monitoring.This study proposes a ... Regular detection and repair for lining cracks are necessary to guarantee the safety and stability of tunnels.The development of computer vision has greatly promoted structural health monitoring.This study proposes a novel encoder–decoder structure,CrackRecNet,for semantic segmentation of lining segment cracks by integrating improved VGG-19 into the U-Net architecture.An image acquisition equipment is designed based on a camera,3-dimensional printing(3DP)bracket and two laser rangefinders.A tunnel concrete structure crack(TCSC)image data set,containing images collected from a double-shield tunnel boring machines(TBM)tunnel in China,was established.Through data preprocessing operations,such as brightness adjustment,pixel resolution adjustment,flipping,splitting and annotation,2880 image samples with pixel resolution of 448×448 were prepared.The model was implemented by Pytorch in PyCharm processed with 4 NVIDIA TITAN V GPUs.In the experiments,the proposed CrackRecNet showed better prediction performance than U-Net,TernausNet,and ResU-Net.This paper also discusses GPU parallel acceleration effect and the crack maximum width quantification. 展开更多
关键词 tunnel lining segment crack detection semantic segmentation convolutional neural network encoder-decoder structure
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Deep learning to estimate ocean subsurface salinity structure in the Indian Ocean using satellite observations
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作者 Jifeng QI Guimin SUN +2 位作者 Bowen XIE Delei LI Baoshu YIN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期377-389,共13页
Accurately estimating the ocean subsurface salinity structure(OSSS)is crucial for understanding ocean dynamics and predicting climate variations.We present a convolutional neural network(CNN)model to estimate the OSSS... Accurately estimating the ocean subsurface salinity structure(OSSS)is crucial for understanding ocean dynamics and predicting climate variations.We present a convolutional neural network(CNN)model to estimate the OSSS in the Indian Ocean using satellite data and Argo observations.We evaluated the performance of the CNN model in terms of its vertical and spatial distribution,as well as seasonal variation of OSSS estimation.Results demonstrate that the CNN model accurately estimates the most significant salinity features in the Indian Ocean using sea surface data with no significant differences from Argo-derived OSSS.However,the estimation accuracy of the CNN model varies with depth,with the most challenging depth being approximately 70 m,corresponding to the halocline layer.Validations of the CNN model’s accuracy in estimating OSSS in the Indian Ocean are also conducted by comparing Argo observations and CNN model estimations along two selected sections and four selected boxes.The results show that the CNN model effectively captures the seasonal variability of salinity,demonstrating its high performance in salinity estimation using sea surface data.Our analysis reveals that sea surface salinity has the strongest correlation with OSSS in shallow layers,while sea surface height anomaly plays a more significant role in deeper layers.These preliminary results provide valuable insights into the feasibility of estimating OSSS using satellite observations and have implications for studying upper ocean dynamics using machine learning techniques. 展开更多
关键词 machine learning convolutional neural network(CNN) ocean subsurface salinity structure(OSSS) Indian Ocean satellite observations
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卷积码的线性系统理论研究 被引量:3
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作者 孟凡刚 刘玉君 巩克现 《信息工程大学学报》 2003年第1期48-53,共6页
本文从卷积码的线性离散时不变系统模型入手,研究了卷积码的代数结构,建立了卷积码的系统状态变量方程描述,并对一般意义上的卷积码提出了比较有效的迭代译码算法。这种译码算法不依赖于信道的统计特性,在误码率较低时具有良好的译码性能。
关键词 卷积码 线性离散时不变系统 代数结构 迭代算法
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PGSLM:Edge-Enabled Probabilistic Graph Structure Learning Model for Traffic Forecasting in Internet of Vehicles
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作者 Xiaozhu Liu Jiaru Zeng +1 位作者 Rongbo Zhu Hao Liu 《China Communications》 SCIE CSCD 2023年第4期270-286,共17页
With the rapid development of the 5G communications,the edge intelligence enables Internet of Vehicles(IoV)to provide traffic forecasting to alleviate traffic congestion and improve quality of experience of users simu... With the rapid development of the 5G communications,the edge intelligence enables Internet of Vehicles(IoV)to provide traffic forecasting to alleviate traffic congestion and improve quality of experience of users simultaneously.To enhance the forecasting performance,a novel edge-enabled probabilistic graph structure learning model(PGSLM)is proposed,which learns the graph structure and parameters by the edge sensing information and discrete probability distribution on the edges of the traffic road network.To obtain the spatio-temporal dependencies of traffic data,the learned dynamic graphs are combined with a predefined static graph to generate the graph convolution part of the recurrent graph convolution module.During the training process,a new graph training loss is introduced,which is composed of the K nearest neighbor(KNN)graph constructed by the traffic feature tensors and the graph structure.Detailed experimental results show that,compared with existing models,the proposed PGSLM improves the traffic prediction performance in terms of average absolute error and root mean square error in IoV. 展开更多
关键词 edge computing traffic forecasting graph convolutional network graph structure learning Internet of Vehicles
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Straw Segmentation Algorithm Based on Modified UNet in Complex Farmland Environment 被引量:3
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作者 Yuanyuan Liu Shuo Zhang +4 位作者 Haiye Yu Yueyong Wang Yuehan Feng Jiahui Sun Xiaokang Zhou 《Computers, Materials & Continua》 SCIE EI 2021年第1期247-262,共16页
Intelligent straw coverage detection plays an important role in agricultural production and the ecological environment.Traditional pattern recognition has some problems,such as low precision and a long processing time... Intelligent straw coverage detection plays an important role in agricultural production and the ecological environment.Traditional pattern recognition has some problems,such as low precision and a long processing time,when segmenting complex farmland,which cannot meet the conditions of embedded equipment deployment.Based on these problems,we proposed a novel deep learning model with high accuracy,small model size and fast running speed named Residual Unet with Attention mechanism using depthwise convolution(RADw–UNet).This algorithm is based on the UNet symmetric codec model.All the feature extraction modules of the network adopt the residual structure,and the whole network only adopts 8 times the downsampling rate to reduce the redundant parameters.To better extract the semantic information of the spatial and channel dimensions,the depthwise convolutional residual block is designed to be used in feature maps with larger depths to reduce the number of parameters while improving the model accuracy.Meanwhile,the multi–level attention mechanism is introduced in the skip connection to effectively integrate the information of the low–level and high–level feature maps.The experimental results showed that the segmentation performance of RADw–UNet outperformed traditional methods and the UNet algorithm.The algorithm achieved an mIoU of 94.9%,the number of trainable parameters was only approximately 0.26 M,and the running time for a single picture was less than 0.03 s. 展开更多
关键词 Straw segmentation convolutional neural network residual structure depthwise convolution attention mechanism
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MAAUNet:Exploration of U-shaped encoding and decoding structure for semantic segmentation of medical image 被引量:1
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作者 SHAO Shuo GE Hongwei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第4期418-429,共12页
In view of the problems of multi-scale changes of segmentation targets,noise interference,rough segmentation results and slow training process faced by medical image semantic segmentation,a multi-scale residual aggreg... In view of the problems of multi-scale changes of segmentation targets,noise interference,rough segmentation results and slow training process faced by medical image semantic segmentation,a multi-scale residual aggregation U-shaped attention network structure of MAAUNet(MultiRes aggregation attention UNet)is proposed based on MultiResUNet.Firstly,aggregate connection is introduced from the original feature aggregation at the same level.Skip connection is redesigned to aggregate features of different semantic scales at the decoder subnet,and the problem of semantic gaps is further solved that may exist between skip connections.Secondly,after the multi-scale convolution module,a convolution block attention module is added to focus and integrate features in the two attention directions of channel and space to adaptively optimize the intermediate feature map.Finally,the original convolution block is improved.The convolution channels are expanded with a series convolution structure to complement each other and extract richer spatial features.Residual connections are retained and the convolution block is turned into a multi-channel convolution block.The model is made to extract multi-scale spatial features.The experimental results show that MAAUNet has strong competitiveness in challenging datasets,and shows good segmentation performance and stability in dealing with multi-scale input and noise interference. 展开更多
关键词 U-shaped attention network structure of MAAUNet convolutional neural network encoding-decoding structure attention mechanism medical image semantic segmentation
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GCN-LSTM spatiotemporal-network-based method for post-disturbance frequency prediction of power systems 被引量:1
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作者 Dengyi Huang Hao Liu +1 位作者 Tianshu Bi Qixun Yang 《Global Energy Interconnection》 EI CAS CSCD 2022年第1期96-107,共12页
Owing to the expansion of the grid interconnection scale,the spatiotemporal distribution characteristics of the frequency response of power systems after the occurrence of disturbances have become increasingly importa... Owing to the expansion of the grid interconnection scale,the spatiotemporal distribution characteristics of the frequency response of power systems after the occurrence of disturbances have become increasingly important.These characteristics can provide effective support in coordinated security control.However,traditional model-based frequencyprediction methods cannot satisfactorily meet the requirements of online applications owing to the long calculation time and accurate power-system models.Therefore,this study presents a rolling frequency-prediction model based on a graph convolutional network(GCN)and a long short-term memory(LSTM)spatiotemporal network and named as STGCN-LSTM.In the proposed method,the measurement data from phasor measurement units after the occurrence of disturbances are used to construct the spatiotemporal input.An improved GCN embedded with topology information is used to extract the spatial features,while the LSTM network is used to extract the temporal features.The spatiotemporal-network-regression model is further trained,and asynchronous-frequency-sequence prediction is realized by utilizing the rolling update of measurement information.The proposed spatiotemporal-network-based prediction model can achieve accurate frequency prediction by considering the spatiotemporal distribution characteristics of the frequency response.The noise immunity and robustness of the proposed method are verified on the IEEE 39-bus and IEEE 118-bus systems. 展开更多
关键词 Synchronous phasor measurement Frequency-response prediction Spatiotemporal distribution characteristics Improved graph convolutional network Long short-term memory network Spatiotemporal-network structure
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A Deep Learning Approach for Prediction of Protein Secondary Structure
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作者 Muhammad Zubair Muhammad Kashif Hanif +4 位作者 Eatedal Alabdulkreem Yazeed Ghadi Muhammad Irfan Khan Muhammad Umer Sarwar Ayesha Hanif 《Computers, Materials & Continua》 SCIE EI 2022年第8期3705-3718,共14页
The secondary structure of a protein is critical for establishing a link between the protein primary and tertiary structures.For this reason,it is important to design methods for accurate protein secondary structure p... The secondary structure of a protein is critical for establishing a link between the protein primary and tertiary structures.For this reason,it is important to design methods for accurate protein secondary structure prediction.Most of the existing computational techniques for protein structural and functional prediction are based onmachine learning with shallowframeworks.Different deep learning architectures have already been applied to tackle protein secondary structure prediction problem.In this study,deep learning based models,i.e.,convolutional neural network and long short-term memory for protein secondary structure prediction were proposed.The input to proposed models is amino acid sequences which were derived from CulledPDB dataset.Hyperparameter tuning with cross validation was employed to attain best parameters for the proposed models.The proposed models enables effective processing of amino acids and attain approximately 87.05%and 87.47%Q3 accuracy of protein secondary structure prediction for convolutional neural network and long short-term memory models,respectively. 展开更多
关键词 convolutional neural network machine learning protein secondary structure deep learning long short-term memory protein secondary structure prediction
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大约束长度卷积码编码器的改进与实现
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作者 张涛涛 王满喜 +1 位作者 荣辉 杨志飞 《通信技术》 2018年第7期1532-1535,共4页
针对传统算法利用计算机搜索大约束长度的卷积码的最大约束长度不超过30的情况,提出了一种改进的大约束长度卷积码搜索算法——基于堆栈结构的搜索算法,利用该搜索算法可以找到约束长度大于30的卷积码编码器。利用卷积码的最大自由距离... 针对传统算法利用计算机搜索大约束长度的卷积码的最大约束长度不超过30的情况,提出了一种改进的大约束长度卷积码搜索算法——基于堆栈结构的搜索算法,利用该搜索算法可以找到约束长度大于30的卷积码编码器。利用卷积码的最大自由距离界,设定该算法搜索到的编码器的距离界的上限和下限,并利用费诺译码算法对找到的大约束长度的卷积码编码器的性能进行检验。结果表明,通过该搜索算法找到的大约束长度卷积码的在同等信噪比情况下的误码率较低。 展开更多
关键词 大约束长度 卷积码 堆栈结构 编码器
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卷积神经网络研究综述 被引量:1685
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作者 周飞燕 金林鹏 董军 《计算机学报》 EI CSCD 北大核心 2017年第6期1229-1251,共23页
作为一个十余年来快速发展的崭新领域,深度学习受到了越来越多研究者的关注,它在特征提取和建模上都有着相较于浅层模型显然的优势.深度学习善于从原始输入数据中挖掘越来越抽象的特征表示,而这些表示具有良好的泛化能力.它克服了过去... 作为一个十余年来快速发展的崭新领域,深度学习受到了越来越多研究者的关注,它在特征提取和建模上都有着相较于浅层模型显然的优势.深度学习善于从原始输入数据中挖掘越来越抽象的特征表示,而这些表示具有良好的泛化能力.它克服了过去人工智能中被认为难以解决的一些问题.且随着训练数据集数量的显著增长以及芯片处理能力的剧增,它在目标检测和计算机视觉、自然语言处理、语音识别和语义分析等领域成效卓然,因此也促进了人工智能的发展.深度学习是包含多级非线性变换的层级机器学习方法,深层神经网络是目前的主要形式,其神经元间的连接模式受启发于动物视觉皮层组织,而卷积神经网络则是其中一种经典而广泛应用的结构.卷积神经网络的局部连接、权值共享及池化操作等特性使之可以有效地降低网络的复杂度,减少训练参数的数目,使模型对平移、扭曲、缩放具有一定程度的不变性,并具有强鲁棒性和容错能力,且也易于训练和优化.基于这些优越的特性,它在各种信号和信息处理任务中的性能优于标准的全连接神经网络.该文首先概述了卷积神经网络的发展历史,然后分别描述了神经元模型、多层感知器的结构.接着,详细分析了卷积神经网络的结构,包括卷积层、池化层、全连接层,它们发挥着不同的作用.然后,讨论了网中网模型、空间变换网络等改进的卷积神经网络.同时,还分别介绍了卷积神经网络的监督学习、无监督学习训练方法以及一些常用的开源工具.此外,该文以图像分类、人脸识别、音频检索、心电图分类及目标检测等为例,对卷积神经网络的应用作了归纳.卷积神经网络与递归神经网络的集成是一个途径.为了给读者以尽可能多的借鉴,该文还设计并试验了不同参数及不同深度的卷积神经网络来分析各参数间的相互关 展开更多
关键词 卷积神经网络 深度学习 网络结构 训练方法 领域数据
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