期刊文献+
共找到5,516篇文章
< 1 2 250 >
每页显示 20 50 100
Transformer-Based Cloud Detection Method for High-Resolution Remote Sensing Imagery
1
作者 Haotang Tan Song Sun +1 位作者 Tian Cheng Xiyuan Shu 《Computers, Materials & Continua》 SCIE EI 2024年第7期661-678,共18页
Cloud detection from satellite and drone imagery is crucial for applications such as weather forecasting and environmentalmonitoring.Addressing the limitations of conventional convolutional neural networks,we propose ... Cloud detection from satellite and drone imagery is crucial for applications such as weather forecasting and environmentalmonitoring.Addressing the limitations of conventional convolutional neural networks,we propose an innovative transformer-based method.This method leverages transformers,which are adept at processing data sequences,to enhance cloud detection accuracy.Additionally,we introduce a Cyclic Refinement Architecture that improves the resolution and quality of feature extraction,thereby aiding in the retention of critical details often lost during cloud detection.Our extensive experimental validation shows that our approach significantly outperforms established models,excelling in high-resolution feature extraction and precise cloud segmentation.By integrating Positional Visual Transformers(PVT)with this architecture,our method advances high-resolution feature delineation and segmentation accuracy.Ultimately,our research offers a novel perspective for surmounting traditional challenges in cloud detection and contributes to the advancement of precise and dependable image analysis across various domains. 展开更多
关键词 CLOUD TRANSFORMER image segmentation remotely sensed imagery pyramid vision transformer
下载PDF
Exploring Motor Imagery EEG: Enhanced EEG Microstate Analysis with GMD-Driven Density Canopy Method
2
作者 Xin Xiong Jing Zhang +3 位作者 Sanli Yi Chunwu Wang Ruixiang Liu Jianfeng He 《Computers, Materials & Continua》 SCIE EI 2024年第6期4659-4681,共23页
The analysis of microstates in EEG signals is a crucial technique for understanding the spatiotemporal dynamics of brain electrical activity.Traditional methods such as Atomic Agglomerative Hierarchical Clustering(AAH... The analysis of microstates in EEG signals is a crucial technique for understanding the spatiotemporal dynamics of brain electrical activity.Traditional methods such as Atomic Agglomerative Hierarchical Clustering(AAHC),K-means clustering,Principal Component Analysis(PCA),and Independent Component Analysis(ICA)are limited by a fixed number of microstate maps and insufficient capability in cross-task feature extraction.Tackling these limitations,this study introduces a Global Map Dissimilarity(GMD)-driven density canopy K-means clustering algorithm.This innovative approach autonomously determines the optimal number of EEG microstate topographies and employs Gaussian kernel density estimation alongside the GMD index for dynamic modeling of EEG data.Utilizing this advanced algorithm,the study analyzes the Motor Imagery(MI)dataset from the GigaScience database,GigaDB.The findings reveal six distinct microstates during actual right-hand movement and five microstates across other task conditions,with microstate C showing superior performance in all task states.During imagined movement,microstate A was significantly enhanced.Comparison with existing algorithms indicates a significant improvement in clustering performance by the refined method,with an average Calinski-Harabasz Index(CHI)of 35517.29 and a Davis-Bouldin Index(DBI)average of 2.57.Furthermore,an information-theoretical analysis of the microstate sequences suggests that imagined movement exhibits higher complexity and disorder than actual movement.By utilizing the extracted microstate sequence parameters as features,the improved algorithm achieved a classification accuracy of 98.41%in EEG signal categorization for motor imagery.A performance of 78.183%accuracy was achieved in a four-class motor imagery task on the BCI-IV-2a dataset.These results demonstrate the potential of the advanced algorithm in microstate analysis,offering a more effective tool for a deeper understanding of the spatiotemporal features of EEG signals. 展开更多
关键词 EEG microstate motor imagery K-means clustering algorithm gaus sian kernel function shannon entropy Lempel-Ziv complexity
下载PDF
Pseudo channel:time embedding for motor imagery decoding
3
作者 MIAO Zhengqing ZHAO Meirong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期308-317,共10页
Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,te... Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,termed traveling-wave based time embedding,utilized as a pseudo channel to enhance the decoding accuracy of MI-EEG signals across various neural network architectures.Unlike traditional neural network methods that fail to account for the temporal dynamics in MI-EEG in individual difference,our approach captures time-related changes for different participants based on a priori knowledge.Through extensive experimentation with multiple participants,we demonstrate that this method not only improves classification accuracy but also exhibits greater adaptability to individual differences compared to position encoding used in Transformer architecture.Significantly,our results reveal that traveling-wave based time embedding crucially enhances decoding accuracy,particularly for participants typically considered“EEG-illiteracy”.As a novel direction in EEG research,the traveling-wave based time embedding not only offers fresh insights for neural network decoding strategies but also expands new avenues for research into attention mechanisms in neuroscience and a deeper understanding of EEG signals. 展开更多
关键词 motor imagery(MI) pseudo channel electroencephalogram(EEG) neural networks
下载PDF
The Analysis of Wolf Imagery in The Company of Wolves
4
作者 WANG Wen-ke 《Journal of Literature and Art Studies》 2024年第7期607-611,共5页
Imagery analysis is a commonly used analytical method in literary analysis.In Angela Carter’s work,the image of wolves is particularly prominent.Her“Werewolf Tetralogy”rewrites traditional culture and subverts trad... Imagery analysis is a commonly used analytical method in literary analysis.In Angela Carter’s work,the image of wolves is particularly prominent.Her“Werewolf Tetralogy”rewrites traditional culture and subverts traditional consciousness,and is the research object of many scholars.Starting from the analysis of the wolf image in The Company of Wolves,this paper uses Deleuze’s Becoming-Animal Theory to explore the construction of harmony between nature,humans and gender relations in The Company of Wolves. 展开更多
关键词 The Company of Wolves Wolf imagery Becoming-Animal
下载PDF
Color Expression and Mood Creation in Imagery Oil Painting
5
作者 Yixuan Xu 《Journal of Contemporary Educational Research》 2024年第1期7-12,共6页
Oil painting is a traditional Western painting form.With the introduction of China and the influence of China’s traditional painting and aesthetics,the painting style became more distinctive,expanding a new developme... Oil painting is a traditional Western painting form.With the introduction of China and the influence of China’s traditional painting and aesthetics,the painting style became more distinctive,expanding a new development direction of oil painting,and thus imagery oil painting came into being.Color,as the most important element in imagery oil painting,mainly plays the role of mood creation and emotional expression.Many creators are good at injecting their thoughts and emotions into the paintings through color matching,so as to enhance the artistic expression of the paintings.This paper analyzes the color expression characteristics of imagery oil painting and explores the color expression techniques in imagery oil painting and mood creation of imagery oil painting from several aspects. 展开更多
关键词 imagery oil painting Color expression Mood creation
下载PDF
Application of a hospital–community–family trinity rehabilitation nursing model combined with motor imagery therapy in patients with cerebral infarction 被引量:7
6
作者 Wen-Wen Li Min Li +1 位作者 Xiao-Juan Guo Fu-De Liu 《World Journal of Clinical Cases》 SCIE 2023年第3期621-628,共8页
BACKGROUND Rehabilitation nursing is considered an indispensable part of the cerebral infarction treatment system.The hospital–community–family trinity rehabilitation nursing model can provide continuous nursing ser... BACKGROUND Rehabilitation nursing is considered an indispensable part of the cerebral infarction treatment system.The hospital–community–family trinity rehabilitation nursing model can provide continuous nursing services across hospitals,communities,and families for patients.AIM To explore the application of a hospital–community–family rehabilitation nursing model combined with motor imagery therapy in patients with cerebral infarction.METHODS From January 2021 to December 2021,88 patients with cerebral infarction were divided into a study(n=44)and a control(n=44)group using a simple random number table.The control group received routine nursing and motor imagery therapy.The study group was given hospital–community–family trinity rehabilitation nursing based on the control group.Motor function(FMA),balance ability(BBS),activities of daily living(BI),quality of life(SS-QOL),activation status of the contralateral primary sensorimotor cortical area to the affected side,and nursing satisfaction were evaluated before and after intervention in both groups.RESULTS Before intervention,FMA and BBS were similar(P>0.05).After 6 months’intervention,FMA and BBS were significantly higher in the study than in the control group(both P<0.05).Before intervention,BI and SS-QOL scores were not different between the study and control group(P>0.05).However,after 6months’intervention,BI and SS-QOL were higher in the study than in the control group(P<0.05).Before intervention,activation frequency and volume were similar between the study and the control group(P>0.05).After 6 months’intervention,the activation frequency and volume were higher in the study than in the control group(P<0.05).The reliability,empathy,reactivity,assurance,and tangibles scores for quality of nursing service were higher in the study than in the control group(P<0.05).CONCLUSION Combining a hospital–community–family trinity rehabilitation nursing model and motor imagery therapy enhances the motor function and balance ability of patients with cerebral infarction,improving their quality of life. 展开更多
关键词 Activities of daily living Cerebral infarction Hospital-community-family trinity rehabilitation nursing model Motor skills Motor imagery therapy Postural balance
下载PDF
YOLOv5-Based Seabed Sediment Recognition Method for Side-Scan Sonar Imagery 被引量:1
7
作者 WANG Ziwei HU Yi +1 位作者 DING Jianxiang SHI Peng 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第6期1529-1540,共12页
Seabed sediment recognition is vital for the exploitation of marine resources.Side-scan sonar(SSS)is an excellent tool for acquiring the imagery of seafloor topography.Combined with ocean surface sampling,it provides ... Seabed sediment recognition is vital for the exploitation of marine resources.Side-scan sonar(SSS)is an excellent tool for acquiring the imagery of seafloor topography.Combined with ocean surface sampling,it provides detailed and accurate images of marine substrate features.Most of the processing of SSS imagery works around limited sampling stations and requires manual interpretation to complete the classification of seabed sediment imagery.In complex sea areas,with manual interpretation,small targets are often lost due to a large amount of information.To date,studies related to the automatic recognition of seabed sediments are still few.This paper proposes a seabed sediment recognition method based on You Only Look Once version 5 and SSS imagery to perform real-time sedi-ment classification and localization for accuracy,particularly on small targets and faster speeds.We used methods such as changing the dataset size,epoch,and optimizer and adding multiscale training to overcome the challenges of having a small sample and a low accuracy.With these methods,we improved the results on mean average precision by 8.98%and F1 score by 11.12%compared with the original method.In addition,the detection speed was approximately 100 frames per second,which is faster than that of previous methods.This speed enabled us to achieve real-time seabed sediment recognition from SSS imagery. 展开更多
关键词 seabed sediment real-time target recognition YOLOv5 model side-scan sonar imagery transfer learning
下载PDF
A double-layer model for improving the estimation of wheat canopy nitrogen content from unmanned aerial vehicle multispectral imagery 被引量:1
8
作者 LIAO Zhen-qi DAI Yu-long +5 位作者 WANG Han Quirine M.KETTERINGS LU Jun-sheng ZHANG Fu-cang LI Zhi-jun FAN Jun-liang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2248-2270,共23页
The accurate and rapid estimation of canopy nitrogen content(CNC)in crops is the key to optimizing in-season nitrogen fertilizer application in precision agriculture.However,the determination of CNC from field samplin... The accurate and rapid estimation of canopy nitrogen content(CNC)in crops is the key to optimizing in-season nitrogen fertilizer application in precision agriculture.However,the determination of CNC from field sampling data for leaf area index(LAI),canopy photosynthetic pigments(CPP;including chlorophyll a,chlorophyll b and carotenoids)and leaf nitrogen concentration(LNC)can be time-consuming and costly.Here we evaluated the use of high-precision unmanned aerial vehicle(UAV)multispectral imagery for estimating the LAI,CPP and CNC of winter wheat over the whole growth period.A total of 23 spectral features(SFs;five original spectrum bands,17 vegetation indices and the gray scale of the RGB image)and eight texture features(TFs;contrast,entropy,variance,mean,homogeneity,dissimilarity,second moment,and correlation)were selected as inputs for the models.Six machine learning methods,i.e.,multiple stepwise regression(MSR),support vector regression(SVR),gradient boosting decision tree(GBDT),Gaussian process regression(GPR),back propagation neural network(BPNN)and radial basis function neural network(RBFNN),were compared for the retrieval of winter wheat LAI,CPP and CNC values,and a double-layer model was proposed for estimating CNC based on LAI and CPP.The results showed that the inversion of winter wheat LAI,CPP and CNC by the combination of SFs+TFs greatly improved the estimation accuracy compared with that by using only the SFs.The RBFNN and BPNN models outperformed the other machine learning models in estimating winter wheat LAI,CPP and CNC.The proposed double-layer models(R^(2)=0.67-0.89,RMSE=13.63-23.71 mg g^(-1),MAE=10.75-17.59 mg g^(-1))performed better than the direct inversion models(R^(2)=0.61-0.80,RMSE=18.01-25.12 mg g^(-1),MAE=12.96-18.88 mg g^(-1))in estimating winter wheat CNC.The best winter wheat CNC accuracy was obtained by the double-layer RBFNN model with SFs+TFs as inputs(R^(2)=0.89,RMSE=13.63 mg g^(-1),MAE=10.75 mg g^(-1)).The results of this study can provide guidance for the accurate and rapid determination of winter wheat canopy nitrogen content in the field. 展开更多
关键词 UAV multispectral imagery spectral features texture features canopy photosynthetic pigment content canopy nitrogen content
下载PDF
Earthquake-triggered landslide interpretation model of high resolution remote sensing imageries based on bag of visual word
9
作者 Ruyue Bai Zegen Wang +7 位作者 Heng Lu Chen Chen Xiuju Liu Guohao Deng Qiang He Zhiming Ren Bin Ding Xin Ye 《Earthquake Research Advances》 CSCD 2023年第2期39-45,共7页
Traditional visual interpretation is often inefficient due to its excessively workload professional knowledge and strong subjectivity.Therefore,building an automatic interpretation model on high spatial resolution rem... Traditional visual interpretation is often inefficient due to its excessively workload professional knowledge and strong subjectivity.Therefore,building an automatic interpretation model on high spatial resolution remote sensing images is the key to the quick and efficient interpretation of earthquake-triggered landslides.Aiming at addressing this problem,a landslide interpretation model of high-resolution images based on bag of visual word(BoVW)feature was proposed.The high-resolution images were pre-processed,and then BoVW feature and support vector machine(SVM)was adopted to establish an automatic landslide interpretation model.This model was further compared with the currently widely used Histogram of Oriented Gradient(HoG)feature extraction model.In order to test the effectiveness of the method,typical landslide images were selected to construct a landslide sample library,which was subsequently utilized as the foundation for conducting an experimental study.The results show that the accuracy of landslide extraction using this method reaches as high as 89%,indicating that the method can be used for the automatic interpretation of landslides in disaster-prone areas,and has high practical value for regional disaster prevention and damage reduction. 展开更多
关键词 Earthquake-triggered landslide BoVW High resolution imagery Interpretation model
下载PDF
Shallow water bathymetry based on a back propagation neural network and ensemble learning using multispectral satellite imagery
10
作者 Sensen Chu Liang Cheng +4 位作者 Jian Cheng Xuedong Zhang Jie Zhang Jiabing Chen Jinming Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第5期154-165,共12页
The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into... The back propagation(BP)neural network method is widely used in bathymetry based on multispectral satellite imagery.However,the classical BP neural network method faces a potential problem because it easily falls into a local minimum,leading to model training failure.This study confirmed that the local minimum problem of the BP neural network method exists in the bathymetry field and cannot be ignored.Furthermore,to solve the local minimum problem of the BP neural network method,a bathymetry method based on a BP neural network and ensemble learning(BPEL)is proposed.First,the remote sensing imagery and training sample were used as input datasets,and the BP method was used as the base learner to produce multiple water depth inversion results.Then,a new ensemble strategy,namely the minimum outlying degree method,was proposed and used to integrate the water depth inversion results.Finally,an ensemble bathymetric map was acquired.Anda Reef,northeastern Jiuzhang Atoll,and Pingtan coastal zone were selected as test cases to validate the proposed method.Compared with the BP neural network method,the root-mean-square error and the average relative error of the BPEL method can reduce by 0.65–2.84 m and 16%–46%in the three test cases at most.The results showed that the proposed BPEL method could solve the local minimum problem of the BP neural network method and obtain highly robust and accurate bathymetric maps. 展开更多
关键词 BATHYMETRY back propagation neural network ensemble learning local minimum problem multispectral satellite imagery
下载PDF
心理意象视域下元宇宙教学赋能高校学生的学习效果研究 被引量:2
11
作者 冷雄辉 杜平 +1 位作者 刘宇 华子荀 《现代教育技术》 CSSCI 2024年第3期52-62,共11页
数字化转型背景下,元宇宙的应用促使教育方式发生了深刻变革。然而,元宇宙教学中仍存在一些共识性问题尚未得到解决,如学生的学习持久性不强、专注度不足、学习效率低下等。对此,文章将元宇宙教学的沉浸性、交互性、构想性作为刺激变量... 数字化转型背景下,元宇宙的应用促使教育方式发生了深刻变革。然而,元宇宙教学中仍存在一些共识性问题尚未得到解决,如学生的学习持久性不强、专注度不足、学习效率低下等。对此,文章将元宇宙教学的沉浸性、交互性、构想性作为刺激变量,将表象能力作为调节变量、心理意象作为中介变量、学习效果作为反应变量,构建了元宇宙教学赋能学习效果的假设模型。在此基础上,文章构建了假设模型的结构方程模型,并进行了中介效应检验和调节作用检验,研究结果显示:元宇宙教学的沉浸性、交互性、构想性均正向影响高校学生的学习效果,心理意象在元宇宙教学影响高校学生学习效果的过程中起中介作用,表象能力在元宇宙教学影响心理意象和高校学生学习效果的过程中发挥调节作用。据此,文章提出高校应将心理意象融入数字素养、开发数字化元宇宙教学平台、培养学生的表象能力等启示。文章的研究有助于高校有针对性地提升元宇宙教学中学生的学习效果,并推动元宇宙技术与元宇宙教学的深度融合。 展开更多
关键词 元宇宙 沉浸性 交互性 构想性 心理意象 表象能力 学习效果
下载PDF
Analysis of the Application of Ink Art in Graphic Design Imagery
12
作者 Ye Wang 《Journal of Contemporary Educational Research》 2023年第1期40-45,共6页
The graphic design industry has been developing rapidly in recent years.People have begun to focus on steering the development of graphic design in the direction of localization,integrating more traditional Chinese el... The graphic design industry has been developing rapidly in recent years.People have begun to focus on steering the development of graphic design in the direction of localization,integrating more traditional Chinese elements,raising the level of acceptance toward graphic design content,and disseminating traditional culture on this basis.Ink art plays an important role in the historical and cultural development process.It uses simple color contrast to construct different situations and possesses unique artistic charm and cultural heritage.Incorporating ink elements into graphic design may enhance the graphic design style and provide inspiration.This article focuses on the reasons,advantages,and strategies of using ink art in graphic design imagery,hoping to provide references for graphic design activities. 展开更多
关键词 Ink art Graphic design imagery Application analysis
下载PDF
媒介变革中网络文学现实观照的幻像强化——从Internet到Sora的技术迁跃 被引量:2
13
作者 禹建湘 张浩翔 《西华大学学报(哲学社会科学版)》 2024年第2期16-22,共7页
网络文学的媒介提供了一种虚拟空间的文化交流与精神对话方式。伴随着互联网媒介生产技术从早期诞生到Sora AI问世的持续发展,文艺同社会生活边界的日渐模糊,进而打破了以往同社会存在遥远距离的束缚,以一种超现实的虚拟空间状态进入社... 网络文学的媒介提供了一种虚拟空间的文化交流与精神对话方式。伴随着互联网媒介生产技术从早期诞生到Sora AI问世的持续发展,文艺同社会生活边界的日渐模糊,进而打破了以往同社会存在遥远距离的束缚,以一种超现实的虚拟空间状态进入社会大众的生活。网络文艺创作将个体“无意识之思”通过超现实的叙事表达在集体“无意识之思”的公共语境空间内,并通过一种“在场”式体验的创作同创作者与阅读者构成共同的语意空间。而由于公共语境空间的平等交流性,读者与创作者都在他者介入的影响下参与到网络文艺在“自我理想”中找寻“理想自我”的过程中。 展开更多
关键词 网络文学 媒介生产 镜像理论 自我幻像 SORA 文生视频
下载PDF
全景影像在城市研究中的应用进展综述
14
作者 侯鑫 王艳 +1 位作者 王绚 范伟 《计算机科学与探索》 CSCD 北大核心 2024年第7期1661-1682,共22页
全景成像技术的进步,街景图像工具的普及,以及人工智能领域的计算机视觉、机器学习和深度学习技术的快速发展,推动了在城市研究中利用全景影像进行大规模、自动化的判别与解析。上述领域的快速发展促使近20年来全景影像、人工智能和城... 全景成像技术的进步,街景图像工具的普及,以及人工智能领域的计算机视觉、机器学习和深度学习技术的快速发展,推动了在城市研究中利用全景影像进行大规模、自动化的判别与解析。上述领域的快速发展促使近20年来全景影像、人工智能和城市研究领域之间涌现了大量交叉成果。借助文献计量工具中常用的CiteSpace和VOSviewer作为分析平台,梳理了全景影像在城市研究中的应用进展。首先利用文献共被引聚类网络与术语时区图,划分了全景影像在城市研究中的三个发展阶段。然后借助合著网络和关键词聚类分析,梳理了各阶段全景影像在城市研究中的合著关系、全景影像的获取方式、图像信息的提取技术,归纳了全景影像在城市研究中的四个主要应用领域:城市建成环境、城市景观环境、城市物理环境和智慧城市。最后在历史分期视域下,剖析了促成全景影像应用领域发展的主要驱动因素,并总结了应用全景影像的城市研究目前存在的挑战和未来的发展趋势。 展开更多
关键词 全景影像 街景图像 城市研究 人工智能 深度学习
下载PDF
基于平均能量差的运动想象EEG通道选择和特征提取
15
作者 孟明 陈思齐 +1 位作者 高云园 佘青山 《传感技术学报》 CAS CSCD 北大核心 2024年第9期1555-1562,共8页
共空间模式(CSP)广泛应用于脑电信号(EEG)的特征提取,合适的通道选择可以有效地提高CSP的分类性能,增加信噪比。根据运动想象信号的平均能量差来进行通道选择和特征提取。首先取两类运动想象信号的通道均值能量作为投票的阈值,根据投票... 共空间模式(CSP)广泛应用于脑电信号(EEG)的特征提取,合适的通道选择可以有效地提高CSP的分类性能,增加信噪比。根据运动想象信号的平均能量差来进行通道选择和特征提取。首先取两类运动想象信号的通道均值能量作为投票的阈值,根据投票差值统计各通道上有明显能量差值试次的数量,基于此来选择出合适的通道,然后对这些通道取能量特征进行归一化,再结合CSP空域特征利用SVM进行分类。在BCI CompetitionⅢData SetsⅣa和BCI Competition IV Dataset SetsⅠ两个数据集上进行的分类实验中,所提出的方法相比于全通道CSP,平均精度分别提高了5.7%和10.9%,通道数分别减少了74.3%和51.7%,验证了所提出的通道选择和特征提取方法的有效性。 展开更多
关键词 EEG 运动想象 CSP SVM 通道选择 能量特征
下载PDF
基于Gaofen-2影像和面向对象的椰子林分类研究
16
作者 罗红霞 戴声佩 +4 位作者 李茂芬 李海亮 胡盈盈 郑倩 禹萱 《热带作物学报》 CSCD 北大核心 2024年第5期1021-1030,共10页
椰子是重要的热带经济作物,海南椰子种植面积占全国的90%以上。快速获取椰子种植面积及其空间分布信息对热带作物产业规划具有十分重要的作用。本研究基于国产Gaofen-2高分辨率卫星影像,以文昌市东郊镇为试验区,开展椰子林遥感分类研究... 椰子是重要的热带经济作物,海南椰子种植面积占全国的90%以上。快速获取椰子种植面积及其空间分布信息对热带作物产业规划具有十分重要的作用。本研究基于国产Gaofen-2高分辨率卫星影像,以文昌市东郊镇为试验区,开展椰子林遥感分类研究。基于最优分割尺度的面向对象分类方法,选取4个光谱特征、5个植被指数和32个纹理特征为辅助参量,构建了4种不同的面向对象分类组合(光谱特征、光谱特征+纹理特征组合、光谱特征+植被指数组合、光谱特征+纹理特征+植被指数特征组合)进行椰子林分类提取,并与基于像元的椰子林分类结果进行对比分析。结果表明:(1)仅采用基于像元分类方法,椰子林的总体分类精度(overall accuracy,OA)和用户精度(user’s accuracy,UA)分别达到87.05%和85.21%。(2)相比基于像元分类,4种面向对象分类组合的OA值提高了5.51%~8.72%。(3)光谱特征和纹理特征组合提取椰子林分类结果最优,OA值和UA值分别达到95.77%和97.15%;光谱特征和植被指数的组合也得到了较好的分类结果,OA值和UA值分别为94.88%和94.42%;所有的光谱特征、植被指数和纹理特征全部参与分类得到的OA值和UA值分别为94.67%和94.17%,低于仅使用光谱特征或者植被指数的组合。综上,国产高分辨率Gaofen-2影像在椰子林遥感精准识别中具有很大的潜力,结合纹理特征的面向对象分类方法可以更准确地提取椰子林分类信息,研究结果可为多云多雨地区大尺度椰子林遥感识别提供技术参考。 展开更多
关键词 椰子林 面向对象分类 分割尺度 Gaofen-2影像
下载PDF
“象”与“意”:云冈石窟武术造像整理与研究
17
作者 孟林盛 徐子齐 +2 位作者 赵霞 胡雅茜 降佳俊 《成都体育学院学报》 CSSCI 北大核心 2024年第2期101-110,共10页
云冈石窟是我国古代佛教石窟造像的杰出代表,是中华民族的文化宝库,不仅在历史、宗教、艺术等方面具有重要的意义,在体育方面也有独特的内涵,具有极高的研究价值。文章从过往研究较少涉及的武术文史视角出发,运用文献资料法、实地调查... 云冈石窟是我国古代佛教石窟造像的杰出代表,是中华民族的文化宝库,不仅在历史、宗教、艺术等方面具有重要的意义,在体育方面也有独特的内涵,具有极高的研究价值。文章从过往研究较少涉及的武术文史视角出发,运用文献资料法、实地调查法、图像分析法、三重证据法等研究方法对云冈石窟中的武术造像进行研究,对其数量、题材、布局、美学形态、文化意象进行全方位地梳理、归纳和探索。研究表明:云冈石窟共有163幅武术造像,涉及射箭、拳技、力士托举、持械四种项目,其宏观布局与微观动作等外在之“象”,以直观的和不可替代的方式印证了北魏时期中华武艺的历史演进,呈现出佛武合一下的东方硕武之美以及南北朝时代特有的胡汉民族融合之“意”。 展开更多
关键词 云冈石窟 石窟造像 武术 武术造像 意象
下载PDF
基于卫星图像的城区屋面分布式光伏潜力评估
18
作者 彭曙蓉 何洁妮 +3 位作者 刘韬文 李彬 苏盛 壮婕 《太阳能学报》 EI CAS CSCD 北大核心 2024年第5期517-526,共10页
结合市辖区层面光伏发展情况以及城市中不同用地的特点,利用卫星图片识别长沙市各地区适合装设分布式光伏的建筑区域。基于太阳高度角和方位角,通过山体阴影分析屋顶上的建筑阴影,计算地区屋面光伏可承载容量。对市场侧、制造商及电网... 结合市辖区层面光伏发展情况以及城市中不同用地的特点,利用卫星图片识别长沙市各地区适合装设分布式光伏的建筑区域。基于太阳高度角和方位角,通过山体阴影分析屋顶上的建筑阴影,计算地区屋面光伏可承载容量。对市场侧、制造商及电网部门的分布式光伏规划进行研究。通过识别结果可为光伏建设方及电网提供明确地域列表及可用面积,以及可实现基于实际建设项目的可新增光分布式光伏装机容量的预测,以期为分布式光伏电站用地不足问题提供新的解决思路。 展开更多
关键词 可再生能源 分布式发电 深度学习 语义分割 卫星图像
下载PDF
融入时空自适应图卷积的运动想象信号解析
19
作者 刘京 康晓慧 +3 位作者 董泽浩 李璇 赵薇 王余 《计算机工程与应用》 CSCD 北大核心 2024年第11期115-128,共14页
基于运动想象(motor imagery,MI)脑电信号的脑机接口(brain-computer interface,BCI)技术在脑卒中患者运动功能康复医疗应用中得到广泛关注和研究。然而MI信号具有低信噪比和个体差异性大的特点,导致脑电信号噪声过大从而影响分类性能... 基于运动想象(motor imagery,MI)脑电信号的脑机接口(brain-computer interface,BCI)技术在脑卒中患者运动功能康复医疗应用中得到广泛关注和研究。然而MI信号具有低信噪比和个体差异性大的特点,导致脑电信号噪声过大从而影响分类性能。因此,如何充分提取MI信号特征以得到更高的单被试分类精度,以及如何训练一个在跨被试上表现优秀的通用模型是MI-BCI系统用于实际应用时急需解决的问题。针对该问题,提出了一种面向不同被试的时空自适应图卷积网络模型,从时空两个维度提取MI特征信号进行分类。模型包括四个模块:空间自适应图卷积模块、时间自适应图卷积模块、特征融合模块和特征分类模块。空间自适应图卷积模块通过通道间的特征相似性动态构造空间图表示,摆脱人为构造的图表示限制。时间自适应图卷积模块将脑电信号的时间序列划为多个时间片段,计算时间段间的相似性,自适应构造脑电信号的时间图表示,消除了噪声影响。最后,进行特征融合并分类。结果表明,在BCIIV2a数据集上使用10-折交叉验证的方法和HGD数据集上分别达到了90.45%和91.64%的平均分类精度,与目前性能较好的方法相比达到了更高的准确率,证明了该模型的有效性;使用迁移学习对不同个体进行实验,平均准确率提高了1.66个百分点,证明了模型的鲁棒性。 展开更多
关键词 脑机接口 运动想象 深度学习 图卷积
下载PDF
传统岭南园林意境空间可理解度量化分析研究
20
作者 郭昊栩 谢轩 赖文波 《西部人居环境学刊》 CSCD 北大核心 2024年第5期110-116,共7页
当前,建筑创作既要反映新时代气象,又要提现优秀文化传统的传承,因而寻找传统文化在新时代建筑体系中的立足点显得尤为重要。作为地域文化的载体,“意境”同样存在于岭南传统园林的空间组构中。利用软件Depthmap比对四个岭南广府地区的... 当前,建筑创作既要反映新时代气象,又要提现优秀文化传统的传承,因而寻找传统文化在新时代建筑体系中的立足点显得尤为重要。作为地域文化的载体,“意境”同样存在于岭南传统园林的空间组构中。利用软件Depthmap比对四个岭南广府地区的传统园林,包括顺德清晖园、东莞可园、番禺余荫山房和佛山梁园等的空间组构的“空间可理解度”值的变化趋势,得出结论:当空间拓扑步数超过6步后,其空间可理解度值皆低于0.5,此时空间理解的模糊性是产生“意境”的空间组构特点。数据化的结论可为新时代岭南园林的营造提供明确的指引,若其他类型的空间组构具有相同特点时,其中的空间感受将与传统岭南园林相类似。量化性的空间关系分析和空间秩序内在逻辑的推理具有清晰的可见性和操作性,使在当代建构模式下营造传统文化意境的空间行为成为一种可把握的肯定性设计活动,为新时代的建筑空间延续传统岭南园林文化内涵提供了理论依据。 展开更多
关键词 岭南园林 空间意境 组构分析 轴线模型 可理解度
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部