Engineering and Technology Journal

Water Flow Simulation of Tigris River Between Samara and Baghdad Based on HEC-RAS Model

Imzahim Alwan; Zahraa Majeed; Ali S. Abbas

Volume 39, Issue 12 , December 2021, , Page 1882-1893

https://doi.org/10.30684/etj.v39i12.1804

Abstract

This work aims to use the digital elevation model (DEM) or 3-Dimensional surface to model and analyze the water flow in the Tigris River. The first stage of this study is based on filed ... Read More ...

Accuracy Assessment of Digital Elevation Models Produced From Different Geomatics Data

Imzahim Abdulkareem; Zina Walid Samuel; Qassim K. Abdullah

Volume 38, 11A , November 2020, , Page 1580-1592

https://doi.org/10.30684/etj.v38i11A.1318

Abstract

Digital Elevation Models (DEM) are now being used in several geospatial applications. DEMs play an important role in the preliminary surveys for constructing dams and reservoirs, highways, ... Read More ...

Effect of DEM and Land Cover Resolutions on Simulated Runoff of Adhaim Watershed by SWAT Model

Mahmoud Saleh Al-Khafaji; Fouad Saeed

Volume 36, 4A , April 2018, , Page 439-448

https://doi.org/10.30684/etj.36.4A.11

Abstract

Accurate estimation of surface runoff by using Soil and Water Assessment Tool (SWAT) model is highly depends on the accuracy of the Digital Elevation Model (DEM), Land Cove and Land ... Read More ... Accurate estimation of surface runoff by using Soil and Water Assessment Tool (SWAT) model is highly depends on the accuracy of the Digital Elevation Model (DEM), Land Cove and Land Use (LC/LU), soil and weather data as input variables. The interactive and complementary effects of the DEM and LC/LU resolutions on the estimated runoff were not taken into consideration in previous studies. This research aims to study these effects on the accuracy of runoff estimation of Adhaim Watershed by using SWAT Model. Twenty surface runoff estimation SWAT models of Adhaim Watershed were implemented using five DEMs with spatial resolution of 30, 50, 90, 250 and 1000m in conjunction with four LC/LUs with spatial resolution of 30, 300, 500 and 1000 m. These models were calibrated and verified on daily time step with the adoption of maximizing Nash and Sutcliffe Efficiency (NS) as an objective function. The results of SWAT models show that specifying the watershed boundary and the total area is highly affected by the DEM resolution without considerable trend. Also, the estimated minimum altitude is inversely related to the DEM resolution, whereas the maximum altitude has a direct relationship. Furthermore, LC/LU resolution is highly affected the number and area of classes that can be distinguished in the LC/LU image. Although, the number of hydrologic response units (HRUs) depends on LC/LU resolution, it was found that this number increases with the increase in LC/LU resolution to a maximum number of HRUs and then it gradually decreases. Whereas, the HRUs has a direct relationship with the DEM resolution and the number of subbasins irregularly changed with the increase of DEM resolution. Results of runoff estimation by using SWAT models show that the estimated runoff is not directly or inversely related to the DEM and LC/LU resolutions. Moreover, the most accurate runoff was not estimated with the highest DEM and LC/LU resolutions, where it is obtained with DEM and LC/LU resolutions of 250 m and 1000 m respectively with NS of 0.74. Accordingly, it is recommended to use these resolutions for estimating the surface runoff of Adhaim Watershed. The relationship between the HRUs and estimated runoff is very complex therefore; more extensive studies are required to comprehend this relationship.

Shirkat Town Monitoring Using Digital Elevation Model

Iman A. Shawkat; Mothana M. Al-Hadithy; Abdul-Razzak T. Ziboon

Volume 29, Issue 2 , January 2011, , Page 312-321

https://doi.org/10.30684/etj.29.2.11

Abstract

In this search, a colored image of French satellite SPOT, of Shirkat country in Salahadeen was used with resolution about (5m) for an area with dimensions (4km×8km), and a digital ... Read More ...

Accuracy Assessment of Srtm-Dem Using GpsMeasurments and Gis Techniques

Ahmed Dhahir Athab

Volume 28, Issue 24 , December 2010, , Page 6915-6928

https://doi.org/10.30684/etj.28.24.7

Abstract

Shuttle Radar Topographic Mission (SRTM) has created datasets of globalelevations that is freely available for modeling and environmental applications. Theglobal availability (almost ... Read More ...

Accuracy Evaluation of SRTM (used in Google Earth) by Comparison with National Topographic maps (1:50,000) in North of Iraq

Haval Abdul-Jabbar Sadeq

Volume 28, Issue 21 , October 2010, , Page 6337-6346

https://doi.org/10.30684/etj.28.21.11

Abstract

Digital Elevation Models (DEM) of a region can be generated from stereopairs of satellite images , enables the work to improve decision-making, take faster and more informed action ... Read More ...

Using 3D Analysis of GIS and Remote Sensing for Modeling Erbil Water Flow and Sewerage Network

Amjed Naser Mohsin

Volume 28, Issue 15 , July 2010, , Page 4910-4925

https://doi.org/10.30684/etj.28.15.2

Abstract

Objective of this paper is to show the logical development of digitaltechnologies that explain and show the movement of water in two- andthree-dimensions (2D and 3D) as observed in ... Read More ...

3-D Virtual Maps Production for Mosul City by USING GIS Techniques

Abdul Razzak T.Ziboon; Amjed Naser Mohsin

Volume 27, Issue 9 , June 2009, , Page 1775-1789

https://doi.org/10.30684/etj.27.9.10

Abstract

With the developments in digital image processing techniques, 3D models of objects are transferred to the digital form from the hardcopy form. 3D visualization was performed by using ... Read More ...

Keywords = Dem

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