检索结果-南通市图书馆

A multi-scale and multi-orientation image retrieval method based on rotation-invariant texture features

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2011年第4期54卷 732-744页

作者： shao zhenfeng,{2. deren & ZHU XianQiang state key laboratory for Information Engineering in surveying,mapping and remote sensing,wuhan university,12. Luoyu Road,wuhan 430079,china 1. state key {2. for Information Engineering in surveying Mapping and Remote Sensing Wuhan University 129 Luoyu Road Wuhan 430079 China

Texture retrieval is a vital branch of content-based image ***-invariant texture retrieval plays a key role in texture *** paper addresses three major issues in rotation-invariant texture retrieval: how to select the texture measurement methods,how to alleviate the influence of rotation for texture retrieval and how to apply the proper multi-scale analysis theory for texture ***,the spectrum influence between a Radon transform and a Log-polar transform was compared after the rotation effect was *** average retrieval performance of wavelet and NSCT with different retrieval parameters was also *** on such analysis,we developed a multi-scale and multi-orientation texture transform spectrum,as well as a rotation-invariant feature vector and its measurement criteria,which can represent the human visual perception sensitive to texture *** a new rotation-invariant texture retrieval algorithm was *** algorithm was developed based on non-parametric statistical features and it applies low band and high frequency directional bands of NSCT coefficients for coarse filtering and fine retrieval,*** on the Brodatz image database show that the constructed rotation-invariant feature vector is appropriate for capturing major orientations and describing detail ***,the combination of the two-step progressive retrieval strategy and multi-scale analysis method can effectively improve retrieval efficiency while ensuring a high precision compared with traditional algorithms.

关键词： NSCT Log-polar Radon rotation-invariant texture retrieval

Spatio-temporal-spectral observation model for urban remote sensing

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2021年第3期24卷 372-386页

作者： zhenfeng shao Wenfu Wu {2. li state key {2. of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina School of remote sensing and Information Engineering Wuhan UniversityWuhanChina

Taking cities as objects being observed,urban remote sensing is an important branch of remote *** the complexity of the urban scenes,urban remote sensing observation requires data with a high temporal resolution,high spatial resolution,and high spectral *** the best of our knowledge,however,no satellite owns all the above ***,it is necessary to coordinate data from existing remote sensing satellites to meet the needs of urban *** this study,we abstracted the urban remote sensing observation process and proposed an urban spatio-temporal-spectral observation model,filling the gap of no existing urban remote sensing *** this study,we present four applications to elaborate on the specific applications of the proposed model:1)a spatiotemporal fusion model for synthesizing ideal data,2.a spatio-spectral observation model for urban vegetation biomass estimation,3)a temporal-spectral observation model for urban flood mapping,and 4)a spatio-temporal-spectral model for impervious surface *** believe that the proposed model,although in a conceptual stage,can largely benefit urban observation by providing a new data fusion paradigm.

关键词： Urban remote sensing spatio-temporal-spectral observation model remote sensing data fusion Earth observation programs

Advances of geo-spatial intelligence at liESMARS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2020年第1期23卷 40-51页

作者： deren li {2. shao Ruiqian Zhang state key {2. of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina School of remote sensing and Information Engineering Wuhan UniversityWuhanChina

The enhancement of computing power,the maturity of learning algorithms,and the richness of application scenarios make Artificial Intelligence(AI)solution increasingly attractive when solving Geo-spatial Information Science(GSIS)*** include image matching,image target detection,change detection,image retrieval,and for generating data models of various *** paper discusses the connection and synthesis between AI and GSIS in block adjustment,image search and discovery in big databases,automatic change detection,and detection of abnormalities,demonstrating that AI can integrate ***,the concept of Earth Observation Brain and Smart Geo-spatial Service(SGSS)is introduced in the end,and it is expected to promote the development of GSIS into broadening applications.

关键词： Artificial intelligence Geospatial Information Science(GSIS) block adjustment big data automatic change detection Earth Observation Brain(EOB) Smart Geospatial Service(SGSS)

利用深度时空自编码网络与多示例学习进行船只异常事件检测

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

武汉大学学报（信息科学版） 2024年第7期49卷 1109-1119页

作者：潘文康邵振峰廖明李先怡宋杨武汉大学测绘遥感信息工程国家重点实验室湖北武汉430079 江西省自然资源事业发展中心江西南昌330025 珠海欧比特宇航科技股份有限公司广东珠海519080 广州市城市规划勘测设计研究院广东广州440100

异常事件检测是交通安全防控的重要支撑技术,也一直是信息科学领域的研究热点。提出了利用深度时空自编码网络与多示例学习进行船只异常事件检测的方法,针对目前无法为模型训练提供精确帧级别标注的问题,引入多示例学习模型,将视频作为... 详细信息

异常事件检测是交通安全防控的重要支撑技术,也一直是信息科学领域的研究热点。提出了利用深度时空自编码网络与多示例学习进行船只异常事件检测的方法,针对目前无法为模型训练提供精确帧级别标注的问题,引入多示例学习模型,将视频作为包,并将视频片段作为包中的示例,通过网络自动学习一个深度异常排序模型,该模型能预测异常视频片段的分数。同时,在特征提取方面,提出了深度时空自编码网络,在空间自编码器中,为了获取更精确的红绿蓝特征,将解码器中的上采样层替换为像素重组层。在时间自编码器中,为了突出运动变化较大的区域,引入基于方差的注意力机制,使快速移动的物体有更大的运动损失,有利于检测出异常事件。还构建了一个新的大规模的船只视频数据集,包括100个真实场景的监控视频以及5类真实的异常事件,分别为海面逗留、非港口靠岸、非港口离岸、超速和越界。该数据集可用于模型的训练与测试。实验结果表明,相比传统的双流网络以及基于图像重构的检测方法,所提出的基于深度时空自编码网络与多示例学习的方法的异常事件检测精度由71.7%提升为82.4%,表明了其在船只异常事件检测上的有效性。

关键词：船只异常事件检测深度时空自编码网络多示例学习船只视频数据集

维普期刊数据库

Spatio-temporal-spectral-angular observation model that integrates observations from UAV and mobile mapping vehicle for better urban mapping

在线全文

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2021年第4期24卷 615-629页

作者： zhenfeng shao Gui Cheng {2. li Xiao Huang Zhipeng Lu Jian liu state key {2. of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina Department of Geosciences University of ArkansasFayettevilleARUSA Leador Spatial Information Technology Corporation WuhanChina

In a complex urban scene,observation from a single sensor unavoidably leads to voids in observations,failing to describe urban objects in a comprehensive *** this paper,we propose a spatio-temporal-spectral-angular observation model to integrate observations from UAV and mobile mapping vehicle platform,realizing a joint,coordinated observation operation from both air and *** develop a multi-source remote sensing data acquisition system to effectively acquire multi-angle data of complex urban ***-source data fusion solves the missing data problem caused by occlusion and achieves accurate,rapid,and complete collection of holographic spatial and temporal information in complex urban *** carried out an experiment on Baisha Town,Chongqing,china and obtained multi-sensor,multi-angle data from UAV and mobile mapping *** first extracted the point cloud from UAV and then integrated the UAV and mobile mapping vehicle point *** inte-grated results combined both the characteristics of UAV and mobile mapping vehicle point cloud,confirming the practicability of the proposed joint data acquisition platform and the effectiveness of spatio-temporal-spectral-angular observation *** with the observation from UAV or mobile mapping vehicle alone,the integrated system provides an effective data acquisition solution toward comprehensive urban monitoring.

关键词： Urban remote sensing data fusion spatio-temporalspectralangular observation model UAV mobile mapping vehicle

Isolating the direct and indirect impacts of urbanization on vegetation carbon sequestration capacity in a large oasis city:evidence from Urumqi,china

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geo-Spatial Information Science 2023年第3期26卷 379-391页

作者： Qingwei Zhuang zhenfeng shao {2. li Xiao Huang Orhan Altan Shixin Wu Yuzhen li state key {2. of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanChina Department of Geosciences University of ArkansasFayettevilleADUSA Department of Geomatics Engineering Istanbul Technical UniversityIstanbulTurkey state key {2. of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqiChina School of Emergency Management Xihua UniversityChengduChina

Oasis cities are deeply affected by human activities in arid and semi-arid *** is an important repository in the carbon cycle of oasis urban *** continuous expansion of urban has a disproportionate impact on the carbon sequestration capacity of *** now,studies have been conducted to quantify the impact of urbanization on vegetation carbon sequestration capacity,the mechanism of such impact remains unclear and lacks systematic investigations,especially in oasis *** the impact mechanism greatly benefits the sustainable development of oasis urban and regional carbon *** fill this knowledge gap,we design a theoretical framework to analyze the impact of urbanization on vegetation carbon sequestration capacity by isolating the direct and indirect impacts in Urumqi,*** results based on Landsat images indicated that the Impervious Surface Areas(ISAs)expanded by 436.98 km2.during *** Net Primary Productivity(NPP)calculated using the Vegetation Photosynthesis Model(VPM)was directly caused by the loss of 51.45 Gg C(1 Gg=109 g).Another important finding proved that the direct carbon loss caused by urbanization did not change the upward trend of the total carbon sequestration capacity of vegetation,but only slowed down this upward trend by 2..86%.Our results provide new insights into urban vegetation carbon sinks and contribute to a better understanding of the uncertainty of urbanization toward carbon *** study will provide scientific data support and suggestions for the sustainable development of oasis cities and the regional carbon budget.

关键词： Oasis urbanization vegetation carbon neutrality net primary productivity(NPP)

From digital Earth to smart Earth

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2014年第8期59卷 722-733页

作者： deren li Yuan Yao {2. shao Le Wang School of remote sensing and Information Engineering Wuhan University state key {2. of Information Engineering in surveying Mapping and Remote Sensing Wuhan University Department of Geography The State University of New York at Buffalo

This article will analyze the achievements of the digital Earth concept and further introduce two key technologies,the internet of things and cloud *** these technologies are accelerating the development of digital Earth toward a new concept—smart *** objective of this article is to discuss the architecture,infrastructure,and typical applications for smart Earth and to elaborate on trends of the movement from digital Earth to smart Earth.

关键词：数字地球智慧地球概念典型应用基础设施发展趋势物联网技术

维普期刊数据库

Challenges and opportunities for the development of MEGACITIES

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2019年第12期12卷 1382-1395页

作者： deren li Jun Ma Tao Cheng JLvan Genderen zhenfeng shao state key {2. of Information Engineering in surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China Collaborative Innovation Center of Geospatial Technology Wuhan UniversityWuhanPeople’s Republic of China Department of Earth Observation Science Faculty ITCUniversity TwenteNetherland

Urbanization is one of the most important social and economic phenomena in the world *** paper reviews the formation of megacities and summarizes the main problems,challenges and opportunities faced by the sustainable development of such large *** discussed include the problems of land subsidence in megacities,environmental issues,traffic problems and energy supply *** sustainable development of megacities in other parts of the world provided the references and experiences for the countermeasures of megacity planning and development in *** vision of Digital Earth and Digital Cities can play a major role in the efficient management and sustainable growth of such megacities all around the world.

关键词： Urbanization smart city sustainable development digital city megacity

Multi-Layer Tree Hierarchical Architecture Based on Web Service

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

wuhan university Journal of Natural Sciences 2006年第3期11卷 539-542页

作者： TONG Hengjian li deren ZHU Xinyan {2. zhenfeng National key laboratory for Information Engineering in {2. Mapping and Remote Sensing Wuhan University Wuhan 430072 Hubei China School of Computer China University of Geosciences Wuhan 430074 Hubei China

To solve the problem of the information share and services integration in population information system, we propose a multi-layer tree hierarchical architecture. The command （Web Service Call） is recursively muhicast from top layer of tree to bottom layer of tree and statistical data are gatbered from bottom layer to top layer. We implemented the architecture by using Web Services technology. In our implementation, client program is the requestor of Web Services, and all leaf nodes of the last layer are only the provider of Web Services. For those nodes of intermediate layers, every node is not only the provider of Web Services, but also the dispatcher of Web Services. We take population census as an cxample to describe the working flow of the architecture.

关键词： information integration information share recursively multicast multi-layer tree hierarchical architecture web service

维普期刊数据库