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Designation of Flood Risk Zones Using the Geographic Information System Technique and Remote Sensing Data in Wasit, Iraq

Rasn Kouther Hasheem, Nsaif Qutaiba Abdulwahhab, Al-Obaidi Mudhar A., John Yakubu Mandafiya

Geomatics and Environmental Engineering

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2021

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Vol. 15, no. 3

129--140

EN

Floods are a great concern for people and infrastructure, and this is an is‑sue which has increased in several regions around the globe in recent years. This study aims to evaluate flood risk areas and create a flood risk map using in‑tegrated remote sensing data and a geographic information system (GIS) in the Wasit governorate – eastern Iraq. Specifically, GIS‑based multi‑criteria analy‑sis (MCA) was used to map flood hazard areas using a four‑criteria layer which is as follows: flow accumulation, slope, rainfall, and elevation. These four layers are standardized and combined using the overlay approach in ArcGIS software and a final map was produced. The study area was divided into five zones based on the results map, namely: very low, low, medium, high, and very high, according to the flood risk area. The resulting map indicates that over 60% of the study area is likely to experience a high and very high level of propensity of flooding. This study could be useful for government planners and decision‑makers to predict potential flooding areas and enhance flood management plans.

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Development of a UAV-based system for the semi-automatic estimation of the volume of earthworks

Ajayi Oluibukun G., Oyeboade Timothy O., Samaila-Ija Hassan A., Adewale Taiwo J.

Reports on Geodesy and Geoinformatics

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2020

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Vol. 110

21--28

EN

One of the challenges faced by surveyors in acquisition of accurate spatial data for mining applications is the risk involved in acquiring data in rugged terrains and difficult or inaccessible areas. With the advent of modern technology, accurate geospatial data can now be safely obtained for proper mining documentation periodically. The use of Unmanned Aerial Vehicles (UAVs) for data acquisition in mine surveying has been a viable means of obtaining reliable geospatial data rapidly and efficiently. The main goal of this study is to develop a semi-automatic UAV-based system for the acquisition of spatial data required for the estimation of the volume of earthworks. A DJI Phantom 4 quadcopter was used for the acquisition of image data of the project site, while the images were processed into a Digital Elevation Model (DEM) using Pix4Dmapper v2.0.1, which was then imported into the MATLAB-based system developed for the automatic estimation of the volume of earthworks. The volume obtained from the automated system was thus compared with the volume obtained directly from the Pix4Dmapper software, having specified a contour interval of 1 and an allowable error rate of ±3% as the standard error. While ±1.02% error was observed in the volume estimated using the Pix4Dmapper, the developed automated system yielded an estimated precision of ±0.81% in its volume estimation, which proves to be more robust for automatic volume estimation in terms of accuracy and precision.

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Development of an integrated Digital Elevation Model for safe takeoff and landing of the aircraft

Ciećko A., Jarmołowski W.

Artificial Satellites : Journal of Planetary Geodesy

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2013

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Vol. 48, No. 4

147--158

EN

The article describes preliminary results of the augmentation of Global Navigation Satellite System/Inertial Navigation System positioning (GNSS/INS) by Digital Elevation Model (DEM) based on the data from the Shuttle Radar Topography Mission (SRTM) and data from field survey. The prototype software is developed to refer the position of the aircraft to DEM and informs the user about the current relevant flight parameters. The number of the parameters may be arbitrarily increased, however, currently we investigate the altitude above the terrain and the aircraft position relative to the descent path and airfield. The study provides some information on the local SRTM accuracy in relation to the field survey of the airfield "Dajtki" - Aeroclub of Warmia and Mazury in Olsztyn.

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Model hydrodynamiczny przepływu wielkich wód rzecznych w Basenie Dolnym Biebrzy

Żelazowska M., Mirosław-Świątek D.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2009

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Vol. 18, No. 3

14--25

PL

W artykule przedstawiono opracowany jednowymiarowy model hydrodynamiczny przepływu fal wezbraniowych na obszarze Basenu Dolnego Biebrzy. W obliczeniach wykorzystano program UNET będący komponentem systemu modelowania przepływu wód w korytach otwartych HEC-RAS. Obszar przepływu rzeki Biebrzy na odcinku Osowiec-Burzyn odwzorowano poprzez 47 przekrojów przez koryto i tereny zalewowe. Kształt koryta uzyskano w wyniku sondowania rzeki, zaś kształt doliny odtworzono z Numerycznego Modelu Terenu. Na podstawie mapy roślinności określono przestrzenne zróżnicowanie współczynnika szorstkości, opisanego za pomocą współczynnika Manninga. Model został zidentyfikowany i zweryfikowany dla danych pomiarowych oraz historycznych wezbrań z lat 1992 oraz 1999.

EN

The aim of this work is calibration of a 1D numerical model of river fl ow within the Lower Biebrza Basin. To simulate the fl ow in the Biebrza valley, a one-dimensional unsteady open - channel flow model UNET, which is a component of computer software HEC-RAS, was applied. The geometry of the river channel and floodplain are described by cross sections in the number of 47. The river cross sections were measured by manual sounding for the main channel part and topography of the floodplain was calculated from the Digital Elevation Model. Plant’s map was used to define spatial hydraulic roughness, which was described by Manning’s coefficient (n value) using Chow’s tables, in the floodplain, and n values for the river channel were selected during calibration process of model. The hydrodynamic model was calibrated for measured and historical date for flood in 1992 and 1999.