414 research outputs found
LiDAR data management pipeline; from spatial database population to web-application visualization
While the existence of very large and scalable Database Management Systems (DBMSs) is well recognized, it is the usage and extension of these technologies to managing spatial data that has seen increasing amounts of research work in recent years. A focused area of this research work involves the handling of very high resolution Light Detection and Ranging (LiDAR) data. While LiDAR has many real world applications, it is usually the purview of organizations interested in capturing and monitoring our environment where it has become pervasive. In many of these cases, it has now become the de facto minimum standard expected when a need to acquire very detailed 3D spatial data is required. However, significant challenges exist when working with these data sources, from data storage to feature extraction through to data segmentation all presenting challenges relating to the very large volumes of data that exist. In this paper, we present the complete LiDAR data pipeline as managed in our spatial database framework. This involves three distinct sections, populating the database, building a spatial hierarchy that describes the available data sources, and spatially segmenting data based on user requirements which generates a visualization of these data in a WebGL enabled web-application viewer. All work presented is in an experimental results context where we show how this approach is runtime efficient given the very large volumes of LiDAR data that are being managed
NeRF: Neural Radiance Field in 3D Vision, A Comprehensive Review
Neural Radiance Field (NeRF), a new novel view synthesis with implicit scene
representation has taken the field of Computer Vision by storm. As a novel view
synthesis and 3D reconstruction method, NeRF models find applications in
robotics, urban mapping, autonomous navigation, virtual reality/augmented
reality, and more. Since the original paper by Mildenhall et al., more than 250
preprints were published, with more than 100 eventually being accepted in tier
one Computer Vision Conferences. Given NeRF popularity and the current interest
in this research area, we believe it necessary to compile a comprehensive
survey of NeRF papers from the past two years, which we organized into both
architecture, and application based taxonomies. We also provide an introduction
to the theory of NeRF based novel view synthesis, and a benchmark comparison of
the performance and speed of key NeRF models. By creating this survey, we hope
to introduce new researchers to NeRF, provide a helpful reference for
influential works in this field, as well as motivate future research directions
with our discussion section
A Tutorial on Geographic Information Systems: A Ten-year Update
This tutorial provides a foundation on geographic information systems (GIS) as they relate to and are part of the IS body of knowledge. The tutorial serves as a ten-year update on an earlier CAIS tutorial (Pick, 2004). During the decade, GIS has expanded with wider and deeper range of applications in government and industry, widespread consumer use, and an emerging importance in business schools and for IS. In this paper, we provide background information on the key ideas and concepts of GIS, spatial analysis, and latest trends and on the status and opportunities for incorporating GIS, spatial analysis, and locational decision making into IS research and in teaching in business and IS curricula
A review of marine geomorphometry, the quantitative study of the seafloor
Geomorphometry, the science of quantitative terrain characterization, has traditionally focused on the investigation of terrestrial landscapes. However, the dramatic increase in the availability of digital bathymetric data and the
increasing ease by which geomorphometry can be investigated using geographic information systems (GISs) and spatial analysis software has prompted interest in employing geomorphometric techniques to investigate the marine environment. Over the last decade or so, a multitude of geomorphometric techniques (e.g. terrain attributes, feature extraction,
automated classification) have been applied to characterize
seabed terrain from the coastal zone to the deep sea. Geomorphometric techniques are, however, not as varied, nor as
extensively applied, in marine as they are in terrestrial environments. This is at least partly due to difficulties associated with capturing, classifying, and validating terrain characteristics underwater. There is, nevertheless, much common
ground between terrestrial and marine geomorphometry applications and it is important that, in developing marine geomorphometry, we learn from experiences in terrestrial studies. However, not all terrestrial solutions can be adopted by
marine geomorphometric studies since the dynamic, four-dimensional (4-D) nature of the marine environment causes
its own issues throughout the geomorphometry workflow.
For instance, issues with underwater positioning, variations
in sound velocity in the water column affecting acousticbased mapping, and our inability to directly observe and
measure depth and morphological features on the seafloor
are all issues specific to the application of geomorphometry in the marine environment. Such issues fuel the need for
a dedicated scientific effort in marine geomorphometry.
This review aims to highlight the relatively recent growth
of marine geomorphometry as a distinct discipline, and offers
the first comprehensive overview of marine geomorphometry
to date. We address all the five main steps of geomorphometry, from data collection to the application of terrain attributes
and features. We focus on how these steps are relevant to marine geomorphometry and also highlight differences and similarities from terrestrial geomorphometry. We conclude with
recommendations and reflections on the future of marine geomorphometry. To ensure that geomorphometry is used and
developed to its full potential, there is a need to increase
awareness of (1) marine geomorphometry amongst scientists already engaged in terrestrial geomorphometry, and of
(2) geomorphometry as a science amongst marine scientists
with a wide range of backgrounds and experiences.peer-reviewe
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