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Web-based interactive visualization of 3D video mosaics using X3D standard

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1259-1265页

作者： CHON Jaechoon LEE Yang-Won shibasaki ryosuke Center for Spatial Information Science the University of Tokyo 4-6-1 Komaba Meguro Tokyo 153-8505 Japan

We present a method of 3D image mosaicing for real 3D representation of roadside buildings, and implement a Web-based interactive visualization environment for the 3D video mosaics created by 3D image mosaicing. The 3D image mo- saicing technique developed in our previous work is a very powerful method for creating textured 3D-GIS data without excessive data processing like the laser or stereo system. For the Web-based open access to the 3D video mosaics, we build an interactive visualization environment using X3D, the emerging standard of Web 3D. We conduct the data preprocessing for 3D video mosaics and the X3D modeling for textured 3D data. The data preprocessing includes the conversion of each frame of 3D video mosaics into concatenated image files that can be hyperlinked on the Web. The X3D modeling handles the representation of concatenated images using necessary X3D nodes. By employing X3D as the data format for 3D image mosaics, the real 3D representation of roadside buildings is extended to the Web and mobile service systems.

关键词：视频镶嵌交互式可视化 Web服务器

Interoperability for Global Observation Data by Ontological Information

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Tsinghua Science and Technology 2008年第S1期13卷 336-342页

作者： Masahiko Nagai Masafumi Ono ryosuke shibasaki Earth Observation Data Integration and Fusion Research Initiative (EDITORIA) The University of Tokyo Center for Spatial Information Science The University of Tokyo

The Ontology registry system is developed to collect, manage, and compare ontological information for integrating global observation data. Data sharing and data service such as support of metadata deign, structuring of data contents, support of text mining are applied for better use of data as data interoperability. Semantic network dictionary and gazetteers are constructed as a trans-disciplinary dictionary. Ontological information is added to the system by digitalizing text based dictionaries, developing 'knowledge writing tool' for experts, and extracting semantic relations from authoritative documents with natural language processing technique. The system is developed to collect lexicographic ontology and geographic ontology.

关键词： ontology interoperability data integration gazetteer semantic network dictionary

Integrating GPS trajectory and topics from Twitter stream for human mobility estimation

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Frontiers of Computer Science 2019年第3期13卷 460-470页

作者： Satoshi MIYAZAWA Xuan SONG Tianqi XIA ryosuke shibasaki Hodaka KANEDA Department of Socio-Cultural Environmental Studies Graduate School of Frontier Sciences The University of Tokyo Chiba 277-8563 Japan Center for Spatial Information Science The University of Tokyo Kashiwa 277-8568 Japan Zenrin DataCom Co. Ltd Tokyo 108-6206 Japan

Understanding urban dynamics and large-scale human mobility will play a vital role in building smart cities and sustainable urbanization. Existing research in this domain mainly focuses on a single data source (e.g., GPS data, CDR data, etc.). In this study, we collect big and heterogeneous data and aim to investigate and discover the relationship between spatiotemporal topics found in geo-tagged tweets and GPS traces from smartphones. We employ Latent Dirichlet Allocation-based topic modeling on geo-tagged tweets to extract and classify the topics. Then the extracted topics from tweets and temporal population distribution from GPS traces are jointly used to model urban dynamics and human crowd flow. The experimental results and validations demonstrate the efficiency of our approach and suggest that the fusion of cross-domain data for urban dynamics modeling is more practical than previously thought.

关键词： GPS trajectory human mobility SNS locationbased social network (LBSN) topic modeling data mining spatiotemporal topic

Development of a GIS-based Decision Support System for Assessing Land Use Status

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维普期刊数据库

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Geo-Spatial Information Science 2004年第1期7卷 72-78页

作者： ryosuke shibasaki Kanichiro Matsumura Center for Spatial Information Science The University of Tokyo 4-6-1 Tokyo Japan

The objectives of this study are to assess land s ui tability and to predict the spatial and temporal changes in land use types (LUTs ) by using GIS-based land use management decision support system. A GIS databas e with data on climate, topography, soil characteristic, irrigation condition, f ertilizer application, and special socioeconomic activities has been developed a nd used for the evaluation of land productivity for different crops by integrati ng with a crop growth model-the erosion productivity impact calculator (EPIC). International food policy simulation model (IFPSIM) is also embedded into GIS fo r the predictions of how crop demands and crop market prices will change under a lternative policy scenarios. An inference engine (IE) including land use choice model is developed to illustrate land use choice behavior based on logit models , which allows to analyze how diversified factors ranging from climate changes, crop price changes to land management changes can affect the distribution of agr icultural land use. A test for integrated simulation is taken in each 0.1° by 0.1° grid cell to predict the change of agricultural land use types at globa l level. Global land use changes are simulated from 1992 to 2050.

关键词：地籍测量 GIS 空间变化数据库土地利用决策支持系统

Scenario-based assessment of future food security

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Journal of Geographical Sciences 2011年第1期21卷 3-17页

作者： WU Wenbin TANG Huajun YANG Peng YOU Liangzhi ZHOU Qingbo CHEN Zhongxin shibasaki ryosuke Key Laboratory of Resources Remote Sensing & Digital Agriculture Ministry of Agriculture Beijing 100081 China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Center for Spatial Information Science University of Tokyo Tokyo 153-8505 Japan International Food Policy Research Institute Washington DC 20006 USA

This paper presents a scenario-based assessment of global future food security. To do that,the socio-economic and climate change scenarios were defined for the future and were linked to an integrated modeling framework. The crop yields simulated by the GIS-based Environmental Policy Integrated Climate （EPIC） model and crop areas simulated by the crop choice decision model were combined to calculate the total food production and per capita food availability,which was used to represent the status of food availability and stability. The per capita Gross Domestic Product （GDP） simulated by IFPSIM model was used to reflect the situation of food accessibility and affordability. Based on these two indicators,the future food security status was assessed at a global scale over a period of approximately 20 years,starting from the year 2000. The results show that certain regions such as South Asia and most African countries will likely remain hotspots of food insecurity in the future as both the per capita food availability and the capacity of being able to import food will decrease between 2000 and 2020. Low food production associated with poverty is the determining factor to starvation in these regions,and more efforts are needed to combat hunger in terms of future actions. Other regions such as China,most Eastern European countries and most South American countries where there is an increase in per capita food availability or an increase in the capacity to import food between 2000 and 2020 might be able to improve their food security situation.

关键词： scenario food security per capita food availability per capita GDP model assessment

Characterizing Spatial Patterns of Phenology in Cropland of China Based on Remotely Sensed Data

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Agricultural Sciences in China 2010年第1期9卷 101-112页

作者： WU Wen-bin YANG Peng TANG Hua-jun ZHOU Qing-bo CHEN Zhong-xin ryosuke shibasaki Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/Key Laboratory of Resources Remote Sensing and Digital Agriculture Ministry of Agriculture Beijing 100081 P.R.China Center for Spatial Information Science University of Tokyo Tokyo 153-8505 Japan

This study used time-series of global inventory modeling and mapping studies （GIMMS） normalized difference vegetation index （NDVI） datasets at a spatial resolution of 8 km and 15-d interval to investigate the spatial patterns of cropland phenology in China. A smoothing algorithm based on an asymmetric Gaussian function was first performed on NDVI dataset to minimize the effects of anomalous values caused by atmospheric haze and cloud contamination. Subsequent processing for identifying cropping systems and extracting phenological parameters, the starting date of growing season （SGS） and the ending date of growing season （EGS） was based on the smoothed NVDI time-series data. The results showed that the cropping systems in China became complex as moving from north to south of China. Under these cropping systems, the SGS and EGS for the first growing season varied largely over space, and those regions with multiple cropping systems generally presented a significant advanced SGS and EGS than the regions with single cropping patterns. On the contrary, the phenological events of the second growing season including both the SGS and EGS showed little difference between regions. The spatial patterns of cropping systems and phenology in Chinese cropland were highly related to the geophysical environmental factors. Several anthropogenic factors, such as crop variety, cultivation levels, irrigation, and fertilizers, could profoundly influence crop phenological status. How to discriminate the impacts of biophysical forces and anthropogenic drivers on phenological events of cultivation remains a great challenge for further studies.

关键词： phenology NDVI time-series cropping systems the starting date of growing season (SGS) the ending date of growing season (EGS) spatial pattern

Regional Variability of the Effects of Land Use Systems on Soil Properties

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Agricultural Sciences in China 2007年第11期6卷 1369-1375页

作者： WU Wen-bin YANG Peng TANG Hua-jun Ongaro Luca shibasaki ryosuke Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences~Key Laboratory of Resources Remote Sensing ＆ Digital Agriculture Ministry of Agriculture Beijing 100081 P.R.China Center for Spatial Information Science University of Tokyo Tokyo 153-8505 Japan Centerfor Climate System Research University of Tokyo Chiba 277-8568 Japan Istituto Agronomico Per L＇Oltremare Florence 4-50131 Italy

In order to explore the regional variability of the effects of land use systems on soil properties, Shouyang County in Shanxi Province and Danling County in Sichuan Province of China were selected as the study areas. Field soil samples of the four land use systems （natural forest, forest plantation, shrubland, and cropland） were collected, respectively, from the two areas. The general statistical tools were used to analyze soil data. The results showed that the influence of land use systems on soil properties was significant. In general, soils in slightly human-disturbed land use systems presented a higher fertility level than those in strongly human-disturbed land use systems in both areas. Furthermore, the impacts of the same land use systems on soil properties showed a distinct regional variability, and even in the same land use system, different farming systems and site management measures （such as irrigation, fertilization, and pesticides） could also lead to the regional heterogeneity in soil properties. The regional variability of land use effects on soil properties reveals the regional variability of the effects of human activities on environmental changes, and could explain the complex relationship between humans and the natural environment in certain ways.

关键词： land use system soil property regional variability human activity

Framework of SAGI Agriculture Remote Sensing and Its Perspectives in Supporting National Food Security

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Journal of Integrative Agriculture 2014年第7期13卷 1443-1450页

作者： SHI Yun JI Shun-ping SHAO Xiao-wei TANG Hua-jun WU Wen-bin YANG Peng ZHANG Yong-jun shibasaki ryosuke Key Laboratory of Agri-Informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Earth Observation Data Integration and Fusion Research Initiative The University of Tokyo School of Remote Sensing and Information Engineering Wuhan University

Remote sensing, in particular satellite imagery, has been widely used to map cropland, analyze cropping systems, monitor crop changes, and estimate yield and production. However, although satellite imagery is useful within large scale agriculture applications （such as on a national or provincial scale）, it may not supply sufifcient information with adequate resolution, accurate geo-referencing, and specialized biological parameters for use in relation to the rapid developments being made in modern agriculture. Information that is more sophisticated and accurate is required to support reliable decision-making, thereby guaranteeing agricultural sustainability and national food security. To achieve this, strong integration of information is needed from multi-sources, multi-sensors, and multi-scales. In this paper, we propose a new framework of satellite, aerial, and ground-integrated （SAGI） agricultural remote sensing for use in comprehensive agricultural monitoring, modeling, and management. The prototypes of SAGI agriculture remote sensing are ifrst described, followed by a discussion of the key techniques used in joint data processing, image sequence registration and data assimilation. Finally, the possible applications of the SAGI system in supporting national food security are discussed.

关键词： SAGI agriculture remote sensing multi-platform data processing food security

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两种NDVI时间序列数据拟合方法比较

农业工程学报 2009年第11期25卷 183-188,F0003页

作者：吴文斌杨鹏唐华俊周清波 shibasaki ryosuke 张莉中国农业科学院农业资源与农业区划研究所北京100081 农业部资源遥感与数字农业重点开放实验室北京100081 日本东京大学空间情报科学研究中心

归一化植被指数(NDVI)时间序列数据拟合目的是降低时序数据的噪声水平,重建高质量的NDVI时序数据,有利于多种参数反演和信息提取。针对国际上普遍应用的两种NDVI时间序列数据拟合方法,即Savitzky-Golay滤波法和非对称性高斯函数拟合法,... 详细信息

归一化植被指数(NDVI)时间序列数据拟合目的是降低时序数据的噪声水平,重建高质量的NDVI时序数据,有利于多种参数反演和信息提取。针对国际上普遍应用的两种NDVI时间序列数据拟合方法,即Savitzky-Golay滤波法和非对称性高斯函数拟合法,该文在介绍两种方法基本概念的基础上,利用直接比较法和间接比较法在中国对两种拟合方法进行了比较分析。结果表明,Savitzky-Golay滤波法和非对称性高斯函数拟合法的拟合效果总体上一致,但二者之间还是存在区域差异性,这种区域差异与两种方法的自身特点和中国区域自然条件紧密相关。不同数据拟合方法的比较研究可以弄清每种方法的优缺点和区域适宜性,有助于研究人员针对不同研究目的和研究区域选择适宜的NDVI数据拟合方法,减少遥感数据处理中的误差,提高研究精度。

关键词：时间序列分析滤波函数拟合,Savitzky-Golay滤波法非对称性高斯函数拟合法