T. H. Mohammadloo, M. Snellen, D. Simons, B. Dierikx, S. Bicknese
{"title":"Using Alternatives to Determine the Shallowest Depth for Bathymetric Charting: Case Study","authors":"T. H. Mohammadloo, M. Snellen, D. Simons, B. Dierikx, S. Bicknese","doi":"10.1061/(ASCE)SU.1943-5428.0000278","DOIUrl":null,"url":null,"abstract":"Methods for gridding multibeam echo sounder (MBES) measurements to equidistant grids are proposed as alternatives to the shallowest measured depth, which is affected by outliers. The approaches considered use a combination of mean and standard deviation of soundings and the regression coefficient from the best fitted plane. These methods along with mean and shallowest depths were applied to two surveyed areas. Two issues were found to be of importance, that is, a proper distribution of soundings and low uncertainties in the depth measurements. Improper sampling excludes using the method employing regression coefficients. For flat areas, the shallowest measured depth was found to be highly influenced by measurement uncertainties, counteracted when using the mean depth. However, the mean depth underestimates the shallowest depth for areas with slopes. When correcting the mean depth for standard deviation, the effect of slopes is accounted for while the influence of measurement uncertainties is decreased compared to shallowest measured depth. Since the uncertainties are dependent on beam angle, depth, and measurement equipment, these issues need to be accounted for in survey planning.","PeriodicalId":54366,"journal":{"name":"Journal of Surveying Engineering","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1061/(ASCE)SU.1943-5428.0000278","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Surveying Engineering","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1061/(ASCE)SU.1943-5428.0000278","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}
引用次数: 4
Abstract
Methods for gridding multibeam echo sounder (MBES) measurements to equidistant grids are proposed as alternatives to the shallowest measured depth, which is affected by outliers. The approaches considered use a combination of mean and standard deviation of soundings and the regression coefficient from the best fitted plane. These methods along with mean and shallowest depths were applied to two surveyed areas. Two issues were found to be of importance, that is, a proper distribution of soundings and low uncertainties in the depth measurements. Improper sampling excludes using the method employing regression coefficients. For flat areas, the shallowest measured depth was found to be highly influenced by measurement uncertainties, counteracted when using the mean depth. However, the mean depth underestimates the shallowest depth for areas with slopes. When correcting the mean depth for standard deviation, the effect of slopes is accounted for while the influence of measurement uncertainties is decreased compared to shallowest measured depth. Since the uncertainties are dependent on beam angle, depth, and measurement equipment, these issues need to be accounted for in survey planning.
期刊介绍:
The Journal of Surveying Engineering covers the broad spectrum of surveying and mapping activities encountered in modern practice. It includes traditional areas such as construction surveys, control surveys, photogrammetric mapping, engineering layout, deformation measurements, precise alignment, and boundary surveying. It also includes newer development such as satellite positioning; spatial database design, quality assurance, and information management of geographic information systems; computer applications involving modeling, data structures, algorithms, and information processing; digital mapping, coordinate systems, cartographic representations, and the role of surveying engineering professionals in an information society.