查看更多>>摘要：The public sector's possibilities of using geospatial technologies are vast and can improve public management.In the Brazilian Federal Government,the use of geospatial technologies is unknown,nor is it known the main applications and public and private actors involved.This research proposes to analyze the geospatial technologies market in the Federal Government between the years 2011 and 2019 through public data of contracts.Through the individual analysis of 600 contracts,we concluded that R$ 804,747,626.99 were negotiated during the period.The contracts mainly involved Remote Sensing and Aerophotogrammetry(50%)and Geographic Information Systems(33%)solutions,applied primarily in the thematic areas of Oil&Gas(39%),Infrastructure(19%),and Environment&Natural Resources(10%).Fototerra was the leading company,providing R$ 155,553,107.03 in products and services.The foremost acquiring institution was the Ministry of Mines and Energy,contracting R$ 410 million,of which Petrobras acquired R$ 311 million.This paper showed how different federal institutions use Geography's technological bases to fulfill their missions,improve social well-being,and con-tribute to a more developed,less unequal,and fairer country.
查看更多>>摘要：Based on a newly proposed spatial data model Spatial Chromatic Model(SCM),we developed a spatial coding scheme,called the full-coded Ordinary Arranged Chromatic Diagram(full-OACD).As a type of spatial tessellation,full-OACD partitions a geographic space into a number of subspaces,such as cells,edges,and vertices.These subspaces are called spatial particles and are assigned with unique codes chromatic codes.The generation,structure,computation,and properties of full-OACD are introduced.Relations between particulate chromatic codes and spatial topology are investigated.Full-OACD is a kind of new discrete spatial coordinate system where the information of real-world entities is embedded.Full-OACD provides an informative and meaningful spatial coding framework for spatial topological analysis and many other potential applications in geospatial information science.
Christiaan Neil BurgerWaldo KleynhansTrienko Lups Grobler
202-220页
查看更多>>摘要：As maritime activities increase globally,there is a greater dependency on technology in monitoring,control,and surveillance of vessel activity.One of the most prominent systems for monitoring vessel activity is the Automatic Identification System(AIS).An increase in both vessels fitted with AIS transponders and satellite and terrestrial AIS receivers has resulted in a significant increase in AIS messages received globally.This resultant rich spatial and temporal data source related to vessel activity provides analysts with the ability to perform enhanced vessel movement analytics,of which a pertinent example is the improvement of vessel location predictions.In this paper,we propose a novel strategy for predicting future locations of vessels making use of historic AIS data.The proposed method uses a Linear Regression Model(LRM)and utilizes historic AIS movement data in the form of a-priori generated spatial maps of the course over ground(LRMAC).The LRMAC is an accurate low complexity first-order method that is easy to implement operationally and shows promising results in areas where there is a consistency in the directionality of historic vessel movement.In areas where the historic directionality of vessel movement is diverse,such as areas close to harbors and ports,the LRMAC defaults to the LRM.The proposed LRMAC method is compared to the Single-Point Neighbor Search(SPNS),which is also a first-order method and has a similar level of computational complexity,and for the use case of predicting tanker and cargo vessel trajectories up to 8 hours into the future,the LRMAC showed improved results both in terms of prediction accuracy and execution time.
查看更多>>摘要：After mastering the key technologies of manufacturing spaceborne Synthetic Aperture Radar(SAR),China's SAR satellites have been successfully launched into space.As the only civil microwave satellite listed in the"National High-resolution Earth Observation System Major Project,"the Gaofen-3(GF-3)01 satellite is the first C-band multi-polarization SAR satellite with a resolution of 1 m.GF-3 series satellites stand out among civil SAR satellites worldwide because of their high resolution,wide swath,high geometric radiation quality,multiple imaging modes,and long operation time.Taking GF-3 series satellites as an example,this study introduces the development of China's civil SAR satellites,as well as their processing strategies and applications.The success of the GF-3 series satellites shows that China's SAR remote sensing technology has stepped into a new era of high-quality and high-precision Earth observations.
查看更多>>摘要：People inherently assess landscapes by creating spontaneous aesthetic liking judgments based on the surrounding stimuli.To understand these judgements objectively,use may be made of the fluency theory of aesthetic pleasure(the psychological processes through which people experience beauty).This study aims to predict people's visual aesthetic preferences based on fluency theory and to correlate these preferences with landscape types and features.An ordinary least squares(OLS)regression model was developed to predict visual aesthetic liking,using image statistics as explanatory variables.We determined types of landscape using Landscape Character Assessment(LCA)and applied viewshed analyses distinguishing between near,medium,and far zones.We identified landscape features by content analysis making use of machine learning-based image recognition supplied by Google Cloud Vision API.The results show that vegetation and geological forms were the most significant features for people's visual aesthetic liking,followed by waterscapes and built structures/human settlements.The viewshed analyses indicated that'medium-altitude,low-gradient artificial areas'were visible in photographs with high aesthetic visual liking in all zones(i.e.,at all distances).When the photographs showing this type of landscape are examined,the artificial areas in the photo-graphs turn out to consist mostly of historical buildings or remains.This finding suggests that historical sites are not just important for their cultural value,but for their visual aesthetic value as well.
NETL
NSTL
万方数据