Détail de l'auteur
Auteur J. Jensen |
Documents disponibles écrits par cet auteur (3)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
![Tris disponibles](./images/orderby_az.gif)
A genetic algorithm approach to moving threshold optimization for binary change detection / J. Im in Photogrammetric Engineering & Remote Sensing, PERS, vol 77 n° 2 (February 2011)
![]()
[article]
Titre : A genetic algorithm approach to moving threshold optimization for binary change detection Type de document : Article/Communication Auteurs : J. Im, Auteur ; Zhong Lu, Auteur ; J. Jensen, Auteur Année de publication : 2011 Article en page(s) : pp 167 - 180 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme génétique
[Termes IGN] détection de changement
[Termes IGN] image Quickbird
[Termes IGN] seuillage d'imageRésumé : (Auteur) This study investigated the use of a genetic algorithm (GA) approach, a widely used optimization method, to identify optimum thresholds for remote sensing-based binary change detection. Automated GA-based calibration models using a moving threshold window (MTW) were developed and tested using a case study. Two sets of the bi-temporal QuickBird imagery were used to evaluate the new optimization models. The GA-based models using MTW were free from the assumption of symmetry of thresholds for difference- or ratio-type of change-enhanced images, unlike traditional binary change detection methods, allowing more flexibility and efficiency in selecting optimum thresholds. Exhaustive search techniques using symmetric threshold window (STW) and MTW were evaluated for comparison. The stability of the GA-based models in terms of accuracy variation was also examined. The GA-based calibration models successfully identified optimum thresholds without a significant decrease in accuracy. The GA-based models using MTW outperformed the GA-based model using STW in both calibration and validation, revealing that optimum thresholds tended to be asymmetric. Multiple change-enhanced images generally resulted in better performance than single change-enhanced images based on the GA-based models. Numéro de notice : A2011-047 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.77.2.167 En ligne : https://doi.org/10.14358/PERS.77.2.167 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30828
in Photogrammetric Engineering & Remote Sensing, PERS > vol 77 n° 2 (February 2011) . - pp 167 - 180[article]Hybridization between Quercus robur and Q. petraea in a mixed oak stand in Denmark / J. Jensen in Annals of Forest Science, Vol 66 n° 7 (October - November 2009)
![]()
[article]
Titre : Hybridization between Quercus robur and Q. petraea in a mixed oak stand in Denmark Titre original : Hybridation entre Quercus robur et Q. petraea dans un peuplement mélangé de chênes au Danemark Type de document : Article/Communication Auteurs : J. Jensen, Auteur ; Anders Larsen, Auteur ; Lene R. Nielsen, Auteur ; Joan Cottrell, Auteur Année de publication : 2009 Article en page(s) : n° 706 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Danemark
[Termes IGN] diversité génétique
[Termes IGN] hybridation naturelle (végétation)
[Termes IGN] peuplement mélangé
[Termes IGN] Quercus pedunculata
[Termes IGN] Quercus sessiliflora
[Vedettes matières IGN] SylvicultureRésumé : (Editeur) Hybridization and mating pattern between Quercus robur and Q. petraea was studied in a 5.8 ha mixed forest stand in Jutland, Denmark which comprises in total 135 Quercus robur and 230 Q. petraea trees. Classification of the oak trees into species was performed using canonical discriminant analysis of a range of leaf morphological traits. Adult trees (365) and offspring (582) were genotyped with eight microsatellite markers. Seedlings were sampled in 2003 and acorns were collected in 2004. Mating patterns of Q. robur and Q. petraea are expected to be different in the northern range of the distribution area and a larger hybridization rate is expected. It is further expected, that pollination from outside sources will be relatively less in small fragmented forest management systems compared to large scale oak forest. The conclusions should be verified through repeated year to year analysis of the mating pattern. Phenological studies revealed that there was no difference in flowering time between species. Data for the adult trees revealed no significant departures from Hardy-Weinberg proportions and there was weak, but significant spatial genetic structure, which supports the idea that the stand is of natural origin. Spatial genetic structure in the first distance class is stronger for Q. petraea. The genetic composition of the offspring was remarkably consistent from year to year. Paternity analysis revealed that, on average, 85% pollination came from fathers within the stand. The direction of the pollen flow varied from year to year. Inter-specific hybridization was high and ranged from 15–17% and from 48–55% for Q. petraea and Q. robur mothers respectively. Paternity analysis revealed that the population was basically outcrossing and only 3.7% of the analysed progeny were the product of selfing. Over the two years of study, approximately 200 trees contributed to the paternity of the next generations.
The study confirms earlier studies with a greater tendency for Q. robur mothers to produce hybrid seeds than Q. petraea mothers. The rate of hybridization is higher in this Danish stand than in comparable studies elsewhere in Europe. Gene flow from outside sources are relatively low.Numéro de notice : A2009-627 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1051/forest/2009058 Date de publication en ligne : 02/10/2009 En ligne : https://www.afs-journal.org/articles/forest/full_html/2009/07/f08308/f08308.html Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=72830
in Annals of Forest Science > Vol 66 n° 7 (October - November 2009) . - n° 706[article]Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité IFN-001-P000668 PER Revue Nogent-sur-Vernisson Salle périodiques Exclu du prêt Interfacing geographic information systems and remote sensing for rural land-use analysis / M.D. Nellis in Photogrammetric Engineering & Remote Sensing, PERS, vol 56 n° 3 (march 1990)
![]()
[article]
Titre : Interfacing geographic information systems and remote sensing for rural land-use analysis Type de document : Article/Communication Auteurs : M.D. Nellis, Auteur ; J. Jensen, Auteur ; K. Lulla, Auteur Année de publication : 1990 Article en page(s) : pp 329 - 331 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] carte d'occupation du sol
[Termes IGN] couvert végétal
[Termes IGN] irrigation
[Termes IGN] milieu rural
[Termes IGN] occupation du sol
[Termes IGN] rendement agricole
[Termes IGN] système d'information géographiqueNuméro de notice : A1990-113 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans En ligne : https://www.asprs.org/wp-content/uploads/pers/1990journal/mar/1990_mar_329-331.p [...] Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=25529
in Photogrammetric Engineering & Remote Sensing, PERS > vol 56 n° 3 (march 1990) . - pp 329 - 331[article]