3D Sidescan with a Small Aperture: Imaging Microbialites at Pavilion Lake
Notice bibliographique
Résumé
This paper demonstrates the capabilities of a small six element Multi-Angle Swath Bathymetry (MASB) system, deployed in freshwater for the purpose of mapping microbialite structures. It is used to provide both high resolution backscatter imagery, and a bathymetric survey. A 3D sidescan sonar, such as the MASB sonar used in this research, differs from conventional sidescan in that a multiple element receive array is utilized to estimate arrival angles of multiple incoming plane waves. Bathymetry information is calculated using the range of a target and angle of arrival (AOA). The desired signal can be separated from multipath signals which would otherwise corrupt imagery of the bottom. Additionally, a the narrow along track beamwidth and short transmitted pulse length allow for a high resolution image of the lakebed. As the 3D sidescan maintains a small aperture (only slightly larger than sidescan), and uses less channels than multibeam systems (hence fewer electronic components), it is an ideal solution for small platform applications (such as autonomous underwater vehicles AUV) and can be produced less expensively than comparable systems. Surveying can also be performed at a variety of depths (due to multipath elimination), making it possible for a wider range of surveying alternatives such as surface boat mounts (convenient for shallow water), and AUVs. Pavilion Lake, in British Columbia, has been chosen as a survey testbed for two reasons. The primary reason is its importance in analogue space research, having been identified by the Canadian Space Agency as a part of the Canadian Analogue Research Network following the work of [1], which originally reported unique microbialite structures in Pavilion Lake. The second reason is that Pavilion Lake is acoustically interesting. Both the microbialite formations and the soft sediment regions provide for a wide range of acoustically diverse lakebed with mean backscattered signal levels that vary by more than 30 dB. In addition, the complexity of the many mound structures in the lake, provide a survey scenario that is well suited to test the performance of the MASB system under varied geometries. Surveys included in this paper were performed on several occasions between June 2005 and September 2006. Comparing various visual ground truth results (using techniques such as diver observations, remotely operated vehicles and GPS referenced drop camera observations) with backscatter imagery, the distribution of microbialites, as recorded with MASB sonar was examined. Microbialites are located not only around the lake perimeter walls, but also on the slopes of the mound features within the lake as well as sparse isolated patches within the basins. The sonar images of microbialites taken at Pavilion Lake facilitated the discovery of structures with previously unknown morphologies at depths greater than those previously recorded in [1]. Finally, comparisons are made between MASB sonar and other more conventional systems. It is shown that 3D sidescan can be implemented at low cost in comparison to multibeam systems, and provide an alternative to conventional sidescan in many applications, supplying not only high density imagery, but also co-located bathymetry.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,007 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».