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Auteur Joni A. Downs |
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Optimizing arbovirus surveillance using risk mapping and coverage modelling / Joni A. Downs in Annals of GIS, Vol 26 n° 1 (January 2020)
[article]
Titre : Optimizing arbovirus surveillance using risk mapping and coverage modelling Type de document : Article/Communication Auteurs : Joni A. Downs, Auteur ; Mehrdad Vaziri, Auteur ; George Deskins, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 13 - 23 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] cartographie des risques
[Termes IGN] données environnementales
[Termes IGN] échantillonnage de données
[Termes IGN] épizootie
[Termes IGN] Floride (Etats-Unis)
[Termes IGN] maladie infectieuse
[Termes IGN] modélisation spatiale
[Termes IGN] optimisation spatiale
[Termes IGN] surveillance sanitaire
[Termes IGN] système d'information géographiqueRésumé : (auteur) Diseases carried by mosquitoes and other arthropods endanger human health globally. Though costly, surveillance efforts are vital for disease control and prevention This paper describes an approach for strategically configuring targeted disease surveillance sites across a study area. The methodology combines risk index mapping and spatial optimization modelling. The risk index is used to identify demand for surveillance, and the maximum covering location problem is used to select a specified number of candidate surveillance sites that covers the maximum amount of risk. The approach is demonstrated using a case study where optimal locations for sentinel surveillance sites are selected for the purposes of detecting eastern equine encephalitis virus in a county in the state of Florida. Optimal sentinel sites were selected under a number of scenarios that modelled different target populations (horses or humans), coverage distances (0.5, 1.0, and 1.5 km), and numbers of sites to select (1–12). Sentinel site selections for the horse and human models displayed different spatial patterns, with horse sites located largely in the west-central region and human ones in the north-central. Minor amounts of spatial overlap between the horse and human sites were observed, especially as coverage distances and numbers of sites were increased. Additionally, a near linear increase in risk coverage was observed as sites were incrementally added to the scenarios. This finding suggests that the number of sentinel sites within the ranges explored should be based on the maximum that can be funded, since they provide similar levels of benefit. Numéro de notice : A2020-117 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/19475683.2019.1688391 Date de publication en ligne : 18/11/2019 En ligne : https://doi.org/10.1080/19475683.2019.1688391 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94736
in Annals of GIS > Vol 26 n° 1 (January 2020) . - pp 13 - 23[article]A time‐geographic approach to quantifying wildlife–road interactions / Rebecca W. Loraamm in Transactions in GIS, vol 23 n° 1 (February 2019)
[article]
Titre : A time‐geographic approach to quantifying wildlife–road interactions Type de document : Article/Communication Auteurs : Rebecca W. Loraamm, Auteur ; Joni A. Downs, Auteur ; David Lamb, Auteur Année de publication : 2019 Article en page(s) : pp 70 - 86 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] comportement
[Termes IGN] données GPS
[Termes IGN] échantillonnage de données
[Termes IGN] faune locale
[Termes IGN] gestion de la vie sauvage
[Termes IGN] interaction spatiale
[Termes IGN] migration animale
[Termes IGN] Mustelidae
[Termes IGN] prisme spatio-temporel
[Termes IGN] route
[Termes IGN] Time-geography
[Termes IGN] voxelRésumé : (auteur) Recent advances in time geography offer new perspectives for studying animal movements and interactions in an environmental context. In particular, the ability to estimate an animal's spatial location probabilistically at temporal sampling intervals between known fix locations allows researchers to quantify how individuals interact with one another and their environment on finer temporal and spatial scales than previously explored. This article extends methods from time geography, specifically probabilistic space–time prisms, to quantify and summarize animal–road interactions toward understanding related diurnal movement behaviors, including road avoidance. The approach is demonstrated using tracking data for fishers (Martes pennanti) in New York State, where the total probability of interaction with roadways is calculated for individuals over the duration tracked. Additionally, a summarization method visualizing daily interaction probabilities at 60 s intervals is developed to assist in the examination of temporal patterns associated with fishers’ movement behavior with respect to roadways. The results identify spatial and temporal patterns of fisher–roadway interaction by time of day. Overall, the methodologies discussed offer an intuitive means to assess moving object location probabilities in the context of environmental factors. Implications for movement ecology and related conservation planning efforts are also discussed. Numéro de notice : A2019-090 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12497 Date de publication en ligne : 17/12/2018 En ligne : https://doi.org/10.1111/tgis.12497 Format de la ressource électronique : url Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92237
in Transactions in GIS > vol 23 n° 1 (February 2019) . - pp 70 - 86[article]Testing time-geographic density estimation for home range analysis using an agent-based model of animal movement / Joni A. Downs in International journal of geographical information science IJGIS, vol 32 n° 7-8 (July - August 2018)
[article]
Titre : Testing time-geographic density estimation for home range analysis using an agent-based model of animal movement Type de document : Article/Communication Auteurs : Joni A. Downs, Auteur ; Mark Horner, Auteur ; David Lamb, Auteur ; Rebecca W. Loraamm, Auteur ; James Anderson, Auteur ; Brittany Wood, Auteur Année de publication : 2018 Article en page(s) : pp 1505 - 1522 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] aire naturelle (écologie)
[Termes IGN] densité de population
[Termes IGN] données localisées
[Termes IGN] méthode fondée sur le noyau
[Termes IGN] migration animale
[Termes IGN] modèle orienté agent
[Termes IGN] population animale
[Termes IGN] Time-geographyRésumé : (auteur) Time-geographic density estimation (TGDE) is a method of movement pattern analysis that generates a continuous intensity surface from a set of tracking data. TGDE has recently been proposed as a method of animal home range estimation, where the goal is to delineate the spatial extents that an animal occupies. This paper tests TGDE’s effectiveness as a home range estimator using simulated movement data. First, an agent-based model is used to simulate tracking data under 16 movement scenarios representing a variety of animal life history traits (habitat preferences, homing behaviour, mobility) and habitat configurations (levels of habitat fragmentation). Second, the accuracy of TGDE is evaluated for four temporal sampling frequencies using three adaptive velocity parameters for 30 sample data sets from each scenario. Third, TGDE accuracy is compared to two other common home range estimation methods, kernel density estimation (KDE) and characteristic hull polygons (CHP). The results demonstrate that TGDE is the most effective at estimating core areas, home ranges and total areas at high sampling frequencies, while CHP performs better at low sampling frequencies. KDE was ineffective across all scenarios explored. Numéro de notice : A2018-281 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658816.2017.1421764 Date de publication en ligne : 03/01/2018 En ligne : https://doi.org/10.1080/13658816.2017.1421764 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90363
in International journal of geographical information science IJGIS > vol 32 n° 7-8 (July - August 2018) . - pp 1505 - 1522[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 079-2018041 RAB Revue Centre de documentation En réserve L003 Disponible A wildlife movement approach to optimally locate wildlife crossing structures / Rebecca W. Loraamm in International journal of geographical information science IJGIS, vol 30 n° 1-2 (January - February 2016)
[article]
Titre : A wildlife movement approach to optimally locate wildlife crossing structures Type de document : Article/Communication Auteurs : Rebecca W. Loraamm, Auteur ; Joni A. Downs, Auteur Année de publication : 2016 Article en page(s) : pp 74 - 88 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] croisement spatial
[Termes IGN] faune
[Termes IGN] migration animale
[Termes IGN] noeud
[Termes IGN] optimisation (mathématiques)
[Termes IGN] route
[Termes IGN] Time-geographyRésumé : (auteur) Transportation networks negatively impact wildlife populations by limiting the physical movement of the individual animal. In extreme cases road presence can lead to collisions between vehicles and animals, resulting in direct mortality if an animal attempts to cross the road. Crossing structures are one commonly used method for reducing wildlife–vehicle collisions. However, limited funding often reduces the amount of structures that may be constructed in practice. Therefore, areas that have the highest probability for animal interactions with roads should be targeted for locating new structures to provide the best possible outcome. This research uses a probabilistic time-geographic strategy coupled with a site selection phase handled by a classical optimization model to site wildlife crossing structures. To achieve optimal site selection, crossing locations are first identified where wildlife frequently cross roads, and then a maximum covering location problem is applied to these areas as demand nodes. The objective is to cover the largest area having the highest probability of interaction given a finite number of crossing structures available to be located. Coverage is defined in terms of fencing distance associated with a particular structure. The approach was demonstrated using Florida panther telemetry data identifying potential crossing structures across two counties in south Florida. The maximal covering location problem (MCLP) was solved for four coverage distances using radio telemetry tracking data, which captured frequent contact with roads. The results identify that the most effective coverage distance is 2000 m, which incrementally covers more total animal–road interaction probability than that of lower fencing distances in the case of the Florida panther. The results illustrate how this new time-geographic approach, combined with location modeling, measures animal–road interactions probabilistically for finding the optimum placement of wildlife crossing structures. Numéro de notice : A2016-011 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2015.1083995 En ligne : http://dx.doi.org/10.1080/13658816.2015.1083995 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79332
in International journal of geographical information science IJGIS > vol 30 n° 1-2 (January - February 2016) . - pp 74 - 88[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 079-2016011 RAB Revue Centre de documentation En réserve L003 Disponible Footprint generation using fuzzy-neighborhood clustering / Jonathon K. Parker in Geoinformatica, vol 17 n° 2 (April 2013)
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Titre : Footprint generation using fuzzy-neighborhood clustering Type de document : Article/Communication Auteurs : Jonathon K. Parker, Auteur ; Joni A. Downs, Auteur Année de publication : 2013 Article en page(s) : pp 285 - 299 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] analyse de groupement
[Termes IGN] classification barycentrique
[Termes IGN] classification floue
[Termes IGN] empreinteRésumé : (Auteur) Geometric footprints, which delineate the region occupied by a spatial point pattern, serve a variety of functions in GIScience. This research explores the use of two density-based clustering algorithms for footprint generation. First, the Density-Based Spatial Clustering with Noise (DBSCAN) algorithm is used to classify points as core points, non-core points, or statistical noise; then a footprint is created from the core and non-core points in each cluster using convex hulls. Second, a Fuzzy-Neighborhood (FN)-DBSCAN algorithm, which incorporates fuzzy set theory, is used to assign points to clusters based on membership values. Then, two methods are presented for delineating footprints with FN-DBSCAN: (1) hull-based techniques and (2) contouring methods based on interpolated membership values. The latter approach offers increased flexibility for footprint generation, as it provides a continuous surface of membership values from which precise contours can be delineated. Then, a heuristic parameter selection method is described for FN-DBSCAN, and the approach is demonstrated in the context of wildlife home range estimation, where the goal is to a generate footprint of an animal’s movements from tracking data. Additionally, FN-DBSCAN is applied to produce crime footprints for a county in Florida. The results are used to guide a discussion of the relative merits of the new techniques. In summary, the fuzzy clustering approach offers a novel method of footprint generation that can be applied to characterize a variety of point patterns in GIScience. Numéro de notice : A2013-160 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s10707-012-0152-0 Date de publication en ligne : 06/03/2012 En ligne : https://doi.org/10.1007/s10707-012-0152-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32298
in Geoinformatica > vol 17 n° 2 (April 2013) . - pp 285 - 299[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 057-2013021 RAB Revue Centre de documentation En réserve L003 Disponible