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Auteur Christopher Pettit |
Documents disponibles écrits par cet auteur (8)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externesGIS and machine learning for analysing influencing factors of bushfires using 40-year spatio-temporal bushfire data / Wanqin He in ISPRS International journal of geo-information, vol 11 n° 6 (June 2022)
Titre : GIS and machine learning for analysing influencing factors of bushfires using 40-year spatio-temporal bushfire data Type de document : Article/Communication Auteurs : Wanqin He, Auteur ; Sara Shirowzhan, Auteur ; Christopher Pettit, Auteur Année de publication : 2022 Article en page(s) : n° 336 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse diachronique
[Termes IGN] apprentissage automatique
[Termes IGN] brousse
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] coefficient de corrélation
[Termes IGN] données météorologiques
[Termes IGN] données spatiotemporelles
[Termes IGN] humidité du sol
[Termes IGN] incendie
[Termes IGN] indice de végétation
[Termes IGN] Nouvelle-Galles du Sud
[Termes IGN] prévention des risques
[Termes IGN] régression linéaire
[Termes IGN] Spark
[Termes IGN] système d'information géographique
[Termes IGN] température de l'airRésumé : (auteur) The causes of bushfires are extremely complex, and their scale of burning and probability of occurrence are influenced by the interaction of a variety of factors such as meteorological factors, topography, human activity and vegetation type. An in-depth understanding of the combined mechanisms of factors affecting the occurrence and spread of bushfires is needed to support the development of effective fire prevention plans and fire suppression measures and aid planning for geographic, ecological maintenance and urban emergency management. This study aimed to explore how bushfires, meteorological variability and other natural factors have interacted over the past 40 years in NSW Australia and how these influencing factors synergistically drive bushfires. The CSIRO’s Spark toolkit has been used to simulate bushfire burning spread over 24 h. The study uses NSW wildfire data from 1981–2020, combined with meteorological factors (temperature, precipitation, wind speed), vegetation data (NDVI data, vegetation type) and topography (slope, soil moisture) data to analyse the relationship between bushfires and influencing factors quantitatively. Machine learning-random forest regression was then used to determine the differences in the influence of bushfire factors on the incidence and burn scale of bushfires. Finally, the data on each influence factor was imported into Spark, and the results of the random forest model were used to set different influence weights in Spark to visualise the spread of bushfires burning over 24 h in four hotspot regions of bushfire in NSW. Wind speed, air temperature and soil moisture were found to have the most significant influence on the spread of bushfires, with the combined contribution of these three factors exceeding 60%, determining the spread of bushfires and the scale of burning. Precipitation and vegetation showed a greater influence on the annual frequency of bushfires. In addition, burn simulations show that wind direction influences the main direction of fire spread, whereas the shape of the flame front is mainly due to the influence of land classification. Besides, the simulation results from Spark could predict the temporal and spatial spread of fire, which is a potential decision aid for fireproofing agencies. The results of this study can inform how fire agencies can better understand fire occurrence mechanisms and use bushfire prediction and simulation techniques to support both their operational (short-term) and strategic (long-term) fire management responses and policies. Numéro de notice : A2022-481 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi11060336 Date de publication en ligne : 05/06/2022 En ligne : https://doi.org/10.3390/ijgi11060336 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100894
in ISPRS International journal of geo-information > vol 11 n° 6 (June 2022) . - n° 336[article]
Titre : Social media as passive geo-participation in transportation planning – how effective are topic modeling & sentiment analysis in comparison with citizen surveys? Type de document : Article/Communication Auteurs : Oliver Lock, Auteur ; Christopher Pettit, Auteur Année de publication : 2020 Article en page(s) : pp 275 - 292 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] artefact
[Termes IGN] contenu généré par les utilisateurs
[Termes IGN] données localisées des bénévoles
[Termes IGN] données massives
[Termes IGN] planification urbaine
[Termes IGN] réseau social
[Termes IGN] sentiment
[Termes IGN] Sydney (Nouvelle-Galles du Sud)
[Termes IGN] traitement du langage naturel
[Termes IGN] transport public
[Termes IGN] ville intelligenteRésumé : (auteur) We live in an era of rapid urbanization as many cities are experiencing an unprecedented rate of population growth and congestion. Public transport is playing an increasingly important role in urban mobility with a need to move people and goods efficiently around the city. With such pressures on existing public transportation systems, this paper investigates the opportunities to use social media to more effectively engage with citizens and customers using such services. This research forms a case study of the use of passively collected forms of big data in cities – focusing on Sydney, Australia. Firstly, it examines social media data (Tweets) related to public transport performance. Secondly, it joins this to longitudinal big data – delay information continuously broadcast by the network over a year, thus forming hundreds of millions of data artifacts. Topics, tones, and sentiment are modeled using machine learning and Natural Language Processing (NLP) techniques. These resulting data, and models, are compared to opinions derived from a citizen survey among users. The validity of such data and models versus the intentions of users, in the context of systems that monitor and improve transport performance, are discussed. As such, key recommendations for developing Smart Cities were formed in an applied research context based on these data and techniques. Numéro de notice : A2020-787 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10095020.2020.1815596 Date de publication en ligne : 21/09/2020 En ligne : https://doi.org/10.1080/10095020.2020.1815596 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96545
in Geo-spatial Information Science > vol 23 n° 4 (December 2020) . - pp 275 - 292[article]
Titre : Extended reality in spatial sciences: A review of research challenges and future directions Type de document : Article/Communication Auteurs : Arzu Çöltekin, Auteur ; Ian M. Lochhead, Auteur ; Marguerite Madden, Auteur ; Sidonie Christophe Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : n° 439 Note générale : bibliographie
The work in this manuscript has been partially funded by (a) Masaryk University internal research grant MUNI/A/1356/2019, (b) Learning Technologies Grant from the University of Georgia Center for Teaching and Learning and (c) University of Applied Sciences and Arts Northwestern Switzerland internal research grant “TP3 VR Labs» (T440-0002-100).Langues : Anglais (eng) Descripteur : [Termes IGN] environnement géographique virtuel
[Termes IGN] réalité augmentée
[Termes IGN] réalité mixte
[Termes IGN] réalité virtuelle
[Termes IGN] recherche et développement
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) This manuscript identifies and documents unsolved problems and research challenges in the extended reality (XR) domain (i.e., virtual (VR), augmented (AR), and mixed reality (MR)). The manuscript is structured to include technology, design, and human factor perspectives. The text is visualization/display-focused, that is, other modalities such as audio, haptic, smell, and touch, while important for XR, are beyond the scope of this paper. We further narrow our focus to mainly geospatial research, with necessary deviations to other domains where these technologies are widely researched. The main objective of the study is to provide an overview of broader research challenges and directions in XR, especially in spatial sciences. Aside from the research challenges identified based on a comprehensive literature review, we provide case studies with original results from our own studies in each section as examples to demonstrate the relevance of the challenges in the current research. We believe that this paper will be of relevance to anyone who has scientific interest in extended reality, and/or uses these systems in their research. Numéro de notice : A2020-418 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi9070439 Date de publication en ligne : 15/07/2020 En ligne : https://doi.org/10.3390/ijgi9070439 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95527
in ISPRS International journal of geo-information > vol 9 n° 7 (July 2020) . - n° 439[article]
Titre : Towards SDG 4: trade-offs for geospatial open educational resources Type de document : Article/Communication Auteurs : Serena Coetzee, Auteur ; Victoria Rautenbach, Auteur ; Arzu Çöltekin, Auteur ; Christopher Pettit, Auteur ; Marguerite Madden, Auteur ; Sidonie Christophe Editeur : International Society for Photogrammetry and Remote Sensing ISPRS Année de publication : 2020 Collection : International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, ISSN 1682-1750 num. 43-B5-2020 Projets : 1-Pas de projet / Conférence : ISPRS 2020, Commission 5, virtual Congress, Imaging today foreseeing tomorrow 31/08/2020 02/09/2020 Nice (en ligne) France Archives Commission 5 Importance : pp 199 - 205 Format : 21 x 30 cm Note générale : bibliographie
This research was supported by a grant from the 2018 ISPRS Education and Capacity Building Initiatives.Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Formation
[Termes IGN] catalogue de données localisées
[Termes IGN] formation initiale
[Termes IGN] métadonnées
[Termes IGN] métadonnées géographiques
[Termes IGN] ressources documentairesRésumé : (auteur) Through the ISPRS scientific initiative presented in this paper, we aim to make geospatial educational resources available and discoverable to those who teach and those who want to learn. In earlier work, we designed and implemented a prototype catalogue for geospatial educational resources, aimed at a target audience in higher education. The success of search and discovery in any catalogue relies heavily on the metadata that describes catalogue entries. Initial feedback showed that users find it difficult to use some of the metadata elements in the prototype to describe their teaching materials. In order to better understand their difficulties and further refine the metadata for describing educational resources that are used for geospatial purposes specifically, we asked a number of participants to describe geospatial educational resources according to four sets of metadata attributes. This paper presents the results of the study and recommends a set of metadata attributes that are specifically useful for geospatial educational resources. Implementation trade-offs are discussed, e.g., deciding between metadata attributes that are very specific or more generic, and catalogue entries that are immediately available to Web search engines without any quality checks vs. catalogue entries that are moderated by a community of educators before publishing them. By providing metadata about geospatial educational resources, the international geospatial community can contribute to the UN Sustainable Development Goal 4 to ensure inclusive and equitable quality education and to promote lifelong learning opportunities for all. Numéro de notice : C2020-010 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.5194/isprs-archives-XLIII-B5-2020-199-2020 Date de publication en ligne : 24/08/2020 En ligne : https://doi.org/10.5194/isprs-archives-XLIII-B5-2020-199-2020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95661 Manual of digital Earth, ch. 7. Geospatial information visualization and extended reality displays / Arzu Çöltekin (2019)
Titre de série : Manual of digital Earth, ch. 7 Titre : Geospatial information visualization and extended reality displays Type de document : Chapitre/Contribution Auteurs : Arzu Çöltekin, Auteur ; Amy L. Griffin, Auteur ; Aidan Slingsby, Auteur ; Anthony C. Robinson, Auteur ; Sidonie Christophe Editeur : Springer International Publishing Année de publication : 2019 Importance : pp 229 - 277 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse géovisuelle
[Termes IGN] géovisualisation
[Termes IGN] immersion
[Termes IGN] réalité augmentée
[Termes IGN] réalité mixte
[Termes IGN] réalité virtuelle
[Termes IGN] visualisation dynamique
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) In this chapter, we review and summarize the current state of the art in geovisualization and extended reality (i.e., virtual, augmented and mixed reality), covering a wide range of approaches to these subjects in domains that are related to geographic information science. We introduce the relationship between geovisualization, extended reality and Digital Earth, provide some fundamental definitions of related terms, and discuss the introduced topics from a human-centric perspective. We describe related research areas including geovisual analytics and movement visualization, both of which have attracted wide interest from multidisciplinary communities in recent years. The last few sections describe the current progress in the use of immersive technologies and introduce the spectrum of terminology on virtual, augmented and mixed reality, as well as proposed research concepts in geographic information science and beyond. We finish with an overview of “dashboards”, which are used in visual analytics as well as in various immersive technologies. We believe the chapter covers important aspects of visualizing and interacting with current and future Digital Earth applications. Numéro de notice : H2019-005 Affiliation des auteurs : LASTIG COGIT+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.1007/978-981-32-9915-3_7 Date de publication en ligne : 20/11/2019 En ligne : http://dx.doi.org/10.1007/978-981-32-9915-3_7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95338 Permalinkvol 117 - July 2016 - Multi-dimensional modeling, analysis and visualization (Bulletin de ISPRS Journal of photogrammetry and remote sensing) / Eric Guilbert
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