BazTech - Yadda

1

Morphometric analysis of Klina River basin using geospatial technology and open access datasets

Çadraku Hazir, Hasa Xhesika

Journal of Water and Land Development

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2023

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no. 58

31--41

EN

According to the Water Framework Directive 2000/60 EC, the river basin is the basic unit for integrated water management at the basin level. In this sense, the knowledge of the morphometric parameters of the river takes on special importance. Morphometric analysis helps in understanding the geo-hydrological characteristics of a river basin. Various authors point out that the morphometric analyses of a drainage watershed demonstrate the dynamic equilibrium that has been achieved due to the interaction between matter and energy. The analysis of morphometric parameters also facilitates and helps to understand the hydrological relations of the basin. This paper deals with the morphometric analysis of sub-basins in the Klina River basin which is located in the northeastern part of the Dukagjini depression. To determine the morphometric parameters in the Klina River basin, the digital relief model from the Advanced Land Observation Satellite (ALOS) platform with a resolution of 20 × 20 m and the ArcMap 10.5 software were used. The results reveal that the total number of streams is 753 of which 602 are 1st order streams, 119 - 2nd order, 23 - 3rd order, 6 - 4th order, 2 - 5th order, and 1 - 6th order streams. The mean bifurcation ratio is 3.81, drainage density is 1.52 km∙km-2. The data and information presented in this study will be helpful and interesting in the plan of the management of Klina River basin which covers an area of 477 km2 within which is estimated to live about 100,000 inhabitants.

2

Runoff Estimation for the Central Region of the Lesser Zab River Watershed Using the SCS-Curve Number Method and GIS

Salman Qasim Mohammed Khudair, Hamdan Ahmed Naseh Ahmed

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

232--245

EN

This study aimed to develop a hydrologic model for the central region (central catchments) located between Dokan and Al-Dibis dams in the Lesser Zab River (LZR) watershed, in Iraq. The hydrologic structure of the study area was prepared based on the DEM layer with 12.5 m spatial resolution by using the GIS environment, and then the HEC-HMS software was used for simulating the main hydrological processes like the infiltration losses, transformation, channel routing, and the baseflow contribution by using the SCS-CN, SCS-UH, Muskingum, and the Recession methods respectively. The corrections of the CN parameter due to the effects of the slope and initial abstraction were used and the resulting CN values for the entire LZR watershed were ranging from 56 to 100. This study concluded the effectivity of using the GIS environment and HEC-HMS software in the continuous rainfall-runoff modelling and achieved very good performance with R2 and NSE criteria of 0.9115 and 0.9 under the calibration phase, while 0.925 and 0.91 values were achieved for the same criteria under the validation phase respectively, also the CN was the most sensitive parameter in the proposed hydrologic model.

3

The application of the methodology to define terrain passability on a detailed level in various configurations

Dawid Wojciech, Pokonieczny Krzysztof, Wyszyński Marek

Aviation and Security Issues

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2023

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No. 1

331--352

EN

The article presents a complete methodology to determine terrain passability as well as its application based on various configurations of input data. The methodology was developed with the use of the methods that had been created by the authors in their previous research projects. The determination of terrain passability consists of two stages: The first stage involves conducting the analysis of micro-relief with the aim to identify impassable spots in the area, while the second stage consists in determining the route for a specific vehicle that will avoid the existing obstacles formed by the micro-relief. Both these analyses generate results based only on a detailed digital terrain model (with a resolution of 1 m) and the traction parameters of the vehicles for which terrain passability is determined. One of the processes that are part of this methodology is the generalisation of the digital terrain model, which significantly improves the efficiency of the performed calculations. Test results demonstrated that the presented methodology enables successful automated generation of passability maps for specific vehicles and the creation of routes for such vehicles. The routes differ depending on the type of vehicle, which results directly from the fact that vehicles have different traction parameters. Nevertheless, the test results were satisfactory and demonstrated that the developed methodology may be applied by bodies that are responsible for planning military operations or crisis management activities.

PL

W artykule zaprezentowano całościową metodykę wyznaczania przejezdności terenu, a także jej zastosowanie w oparciu o różne konfiguracje danych wejściowych. Do przygotowania metodyki wykorzystano metody, które zostały opracowane przez autorów we wcześniejszych badaniach. Wyznaczanie przejezdności terenu składa się z dwóch etapów: przeprowadzenie analizy mikrorzeźby, której celem jest wskazanie w terenie miejsc nieprzejezdnych, a także wyznaczenie trasy dla konkretnego pojazdu, która omijać będzie występujące w terenie przeszkody związane z mikrorzeźbą. Obie analizy do generowania wyników wykorzystują jedynie szczegółowy numeryczny model terenu (o rozdzielczości 1 m) oraz parametry trakcyjne pojazdów, dla których wyznaczana jest przejezdność terenu. Jednym z procesów wchodzących w skład metodyki jest uogólnienie numerycznego modelu terenu, które znacznie zwiększa wydajność prowadzonych obliczeń. Wyniki badań pokazały, że opracowana metodyka z powodzeniem automatycznie opracowuje mapy przejezdności dla konkretnych pojazdów, a także wyznacza dla nich trasy przejazdu. Są one inne dla różnych pojazdów, co wynika bezpośrednio z faktu, że posiadają one odmienne parametry trakcyjne. Niemniej jednak, zadowalające wyniki badań pokazały, że opracowana metodyka może być stosowana przez organy odpowiedzialne za planowanie operacji wojskowych czy zarządzania kryzysowego.

4

A Proposed Merging Methods of Digital Elevation Model Based on Artificial Neural Network and Interpolation Techniques for Improved Accuracy

Alemam Mustafa K., Yong Bin, Sani-Mohammed Abubakar

Artificial Satellites : Journal of Planetary Geodesy

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2023

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Vol. 58, No. 3

122--170

EN

The digital elevation model (DEM) is one of the most critical sources of terrain elevations, which are essential in various geoscience applications. Most of these applications need precise elevations, which are available at a high cost. Thus, sources like the Shuttle Radar Topography Mission (SRTM) DEM are frequently accessible to all users but with low accuracy. Consequently, many studies have tried to improve the accuracy of DEMs acquired from these free sources. Importantly, using the SRTM DEM is not recommended for an area that partly contains high-accuracy data. Thus, there is a need for a merging technique to produce a merged DEM of the whole area with improved accuracy. In recent years, advancements in geographic information systems (GIS) have improved data analysis by providing tools for applying merging techniques (like the minimum, maximum, last, first, mean, and blend (conventional methods)) to improve DEMs. In this article, DEM merging methods based on artificial neural network (ANN) and interpolation techniques are proposed. The methods are compared with other existing methods in commercial GIS software. The kriging, inverse distance weighted (IDW), and spline interpolation methods were considered for this investigation. The essential step for achieving the merging stage is the correction surface generation, which is used for modifying the SRTM DEM. Moreover, two cases were taken into consideration, i.e., the zeros border and the H border. The findings show that the proposed DEM merging methods (PDMMs) improved the accuracy of the SRTM DEM more than the conventional methods (CDMMs). The findings further show that the PDMMs of the H border achieved higher accuracy than the PDMMs of the zeros border, while kriging outperformed the other interpolation methods in both cases. The ANN outperformed all methods with the highest accuracy. Its improvements in the zeros and H border respectively reached 22.38% and 75.73% in elevation, 34.67% and 54.83% in the slope, and 40.28% and 52.22% in the aspect. Therefore, this approach would be cost-effective, especially in critical engineering projects.

5

The process of modelling the elevation surface of a coastal area using the fusion of spatial data from different sensors

Włodarczyk-Sielicka Marta, Bodus-Olkowska Izabela, Łącka Małgorzata

Oceanologia

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2022

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No. 64 (1)

22--34

EN

Information regarding the depth distribution in a specific aquatic area is not also crucial for the safety of navigation, but also for modelling environmental processes, such as the quick establishment of marine-land boundaries or assessments of flood risk areas. Using elevation data from different available sources can be very convenient for individuals who wish to conduct quick analysis or need to obtain data covering a large area without the need for data collection and surveys. This study proposes a method of combining spatial data from different sources during surface modelling of a coastal area. The spatial data used for elevation surface modelling included hydrographic and topographic data, which are often collected separately for various purposes. Data are saved in different formats with various resolutions and accuracies; thus, a uniform surface model that will allow for easy and accurate analysis is currently lacking. The main aim of this study was to create a model of the surface of a coastal area using input data from various sources with the highest possible accuracy. This paper presents the available spatial data sources for coastal areas, along with the data pre-processing process. Furthermore, spatial data fusion is introduced, along with the results. The entire process of creating the uniform surface model consisted of several steps that are described in detail and visualised. The obtained model was visualised using a three-dimensional map.

6

Estimation of roughness and zero-displacement heights over Baghdad utilizing remote sensing and GIS techniques

Mohsen Al-Zahraa A., Al-Jiboori Monim H., Al-Timimi Yaseen K.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2021

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Vol. 30, No. 1

171--181

EN

The objective of this study was to estimate the height of roughness element (ZH) and zero-displacement length (Zd) for Baghdad city using remote sensing and GIS techniques and resources such as DEM, DSM, and shapefile. The difference between DEM and DSM produced digital height model which represents the height of the roughness element for the region, which was used to determine the zero-displacement height. The results showed that the variations in Zd values depend strongly on ZH. Rusafa had the highest Zd (15.8 m) while Dora had the lowest values (4.7 m). Thus, Baghdad city has medium density classification according to the results of Zd and ZH values.

7

Evaluation of Impact of Land Use in Adjacent Areas Causing Damage to Dirt Roads Using GIS Tools - Case Study

Fiedler Michał, Stachowski Piotr

Rocznik Ochrona Środowiska

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2020

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Tom 22, cz. 1

281--293

EN

Surface run-off from areas adjacent to dirt roads may cause considerable damage to these roads. The degree of damage is determined from the amount of flowing water, run-off intensity as well as sites, in which run-off reaches the roads. These parameters result from soil conditions, as well as natural relief and the land form modified by tillage operations. Another parameter influencing the formation and the degree of erosion is connected with maintenance operations regularly repeated in the life cycle of these roads, such as e.g. surface levelling or use of paving materials. The analysis involved GIS tools, which made it possible to consider the impact of spatial variability in the surroundings of such roads on the incidence of adverse factors. The application of LiDAR data made it possible to indicate the formation of surface run-off routes and the resulting threats of damage to dirt roads.

PL

Spływy powierzchniowe z terenów przyległych do dróg gruntowych mogą wywoływać znaczne uszkodzenia tych dróg. Stopień uszkodzeń wynika z ilości spływającej wody, intensywności spływu oraz miejsc, w których spływy docierają do dróg. Parametry te wynikają z warunków glebowych oraz naturalnego i wynikającego ze stosowanych zabiegów uprawowych ukształtowania powierzchni terenu. Kolejnym parametrem wpływającym na powstawanie i stopień erozji są cykliczne zabiegi konserwacyjne stosowane w procesie utrzymania tych dróg, jak np. wyrównywanie powierzchni czy stosowanie materiałów utwardzających. W analizie zagadnienia zastosowano narzędzia GIS pozwalające na uwzględnienie wpływu przestrzennej zmienności otoczenia takich dróg na występowanie czynników szkodliwych. Wykorzystanie danych LIDAR pozwoliło na wskazanie ścieżek formowania się spływów powierzchniowych i wynikających z nich zagrożeń uszkodzeniami dróg gruntowych.

8

Multiscale comparison of LS factor calculation methods based on diferent fow direction algorithms in Susa Ancient landscape

Khanifar Javad, Khademalrasoul Ataallah

Acta Geophysica

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2020

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Vol. 68, no. 3

783--793

EN

Topography (LS factor) is one of the most important controlling factors of soil characteristics and geomorphic processes in the landscape. This study was performed in the Susa Ancient site and aimed to compare the estimation of three diferent LS factor calculation methods in which the catchment area was calculated based on seven types of fow direction algorithms using DEM with fve spatial resolutions. For calculating the LS factor, the catchment area attribute was used to calculate the slope length based on the fow direction. Results showed that the catchment area is an entirely scale-dependent attribute and with decreasing the spatial resolution, the statistical values of catchment area increased. At high spatial resolution, the diferent fow direction algorithms despite the diference in the fow distribution to the neighboring cells, but the catchment area attributes calculated based on them, are statistically slightly diferent. By upscaling, the LS factor values calculated in Boehner and Selige and Moore et al. methods increase, whereas in Desmet and Govers method decrease and this change rate indicates that the LS factors calculated by these three methods have the lowest sensitivity to the slope length. At a same scale, the statistics of LS factors calculated based on diferent fow direction algorithms depicted no considerable diferent. The single fow direction algorithms of Rh and D8 cause to calculate the lowest mean values of LS factors at all spatial resolutions. The diference between frequency distributions of the LS factors calculated by these three methods increases with decreasing spatial resolution. The statistical analysis of this study confrms that estimating the LS factor scale and calculation method are more important than the type of fow direction algorithm.

9

A new trend function based regression kriging for spatial modeling of groundwater hydraulic heads under the sparse distribution of measurement sites

Mohanasundaram S., Udmale Parmeshwar, Shrestha Sangam, Baghel Triambak, Doshi Smit Chetan, Narasimhan Balaji, Suresh Kumar G.

Acta Geophysica

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2020

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Vol. 68, no. 3

751--772

EN

Discrete groundwater level datasets are interpolated often using kriging group of models to produce a spatially continuous groundwater level map. There is always some level of uncertainty associated with diferent interpolation methods. Therefore, we developed a new trend function with the mean groundwater level as a drift variable in the regression kriging approach to predict the groundwater levels at the unvisited locations. Groundwater level data for 29 observation wells in Adyar River Basin were used to assess the performance of the developed regression kriging models. The cross-validation results shows that the proposed regression kriging method in the spatial domain outperforms other physical and kriging-based methods with R2 values of 0.96 and 0.98 during pre-monsoon and post-monsoon seasons, respectively.

10

Urban area change visualization and analysis using high density spatial data from time series aerial images

Altuntas Cihan

Reports on Geodesy and Geoinformatics

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2019

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Vol. 107

1--12

EN

Urban changes occur as a result of new constructions or destructions of buildings, extensions, excavation works and earth fill arising from urbanization or disasters. The fast and efficient detection of urban changes enables us to update geo-databases and allows effective planning and disaster management. This study concerns the visualization and analysis of urban changes using multi-period point clouds from aerial images. The urban changes in the city centre of the Konya Metropolitan area within arbitrary periods between the years 1951, 1975, 1998 and 2010 were estimated after comparing the point clouds by using the iterative closest point (ICP) algorithm. The changes were detected with the point-to-surface distances between the point clouds. The degrees of the changes were expressed with the RMSEs of these point-to-surface distances. In addition, the change size and proportion during the historical periods were analysed. The proposed multi-period change visualization and analysis method ensures strict management against unauthorized building or excavation and more operative urban planning.

11

Osuwiska w Sudetach

Sikora Rafał, Wojciechowski Tomasz

Przegląd Geologiczny

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2019

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Vol. 67, nr 5

360--368

EN

This paper presents the results of analysis of landslides distribution in the Sudetes (SW Poland). Our study was based on the analysis of the LiDAR-data digital elevation model and integrated with investigations of different factors for landslide development. The results of the study showed relationships between the spatial distribution of landslides and geology of their basement. For the areas built by Permo-Mesozoic and late Variscan sedimentary and volcanogenic rocks, the tectonic and lithological factors are predominant for landslide occurrences. The largest landslides have a tectonic affinity and represent a frontal type of geometry. The relationships between geological conditions and mass movements were also confirmed by the constructed landslide susceptibility map of the Sudetes.

12

Dwa równoległe pomiary wietrzności jako dokładna ocena lokalnych zasobów energii wiatru

Gnyp P.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2018

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T. 8, nr 3

69--72

PL

Pomiary wietrzności przeprowadzono przy użyciu dwóch masztów pomiarowych oddalonych od siebie o 17,6 km. Wyznaczono dwa numeryczne modele terenu – numeryczny model wysokościowy terenu oraz numeryczny model szorstkości terenu. Podczas analizy danych pomiarowych zauważono znaczące różnice w zmierzonej prędkości wiatru pomiędzy masztami pomiarowymi. Dodatkowy pomiar wietrzności może okazać się niezbędny dla uzyskania pełnej informacji o charakterze wietrzności dla danej lokalizacji.

EN

The wind measurements were made using two measuring masts spaced 17.6 km apart. Two numerical terrain models were identified - the numerical terrain model and the numerical roughness model. During measurement data analysis significant differences in measured wind speed between measuring masts were noted. Additional wind measurements may be necessary to obtain complete wind quality information for the location.

13

Thematic mapping of avalanche-threatened areas

Babiy L., Hrytskiv N., Laykun L.

Geomatics, Landmanagement and Landscape

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2017

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no. 4

15--26

EN

Providing avalanche-threatened areas with modern thematic data mapping is an urgent task. It will allow us to predict and prevent catastrophic consequences of snow avalanches. The purpose of this paper is to create a set of thematic raster maps of Polonyna Borzhava mountain ridge, including a physical map, a map of relative avalanche hazards, and a map of avalanche paths, on the basis of analysing certain morphometric and environmental factors. Modelling and analysing morphometric parameters of the ridge surface were implemented, and they were represented as factors of avalanche occurrence. The areas with consistent snow avalanche occurrence in the Polonyna Borzhava mountain ridge were allocated by combining cartographic material, remote sensing data, statistical meteorological data and some geomorphometric data about the surface in one unified geographic information system. Thematic mapping of snow avalanches of Polonyna Borzhava ridge has been implemented in the scale of 1:50000. The resulting thematic maps can be used when developing winter tourist routes.

14

Investigation of the accuracy of Google Earth elevation data

El-Ashmawy K. L. A.

Artificial Satellites : Journal of Planetary Geodesy

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2016

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Vol. 51, No. 3

89--97

EN

Digital Elevation Models (DEMs) comprise valuable source of elevation data required for many engineering applications. Contour lines, slope - aspect maps are part of their many uses. Moreover, DEMs are used often in geographic information systems (GIS), and are the most common basis for digitally-produced relief maps. This paper proposes a method of generating DEM by using Google Earth elevation data which is easier and free. The case study consisted of three different small regions in the northern beach in Egypt. The accuracy of the Google earth derived elevation data are reported using root mean square error (RMSE), mean error (ME) and maximum absolute error (MAE). All these accuracy statistics were computed using the ground coordinates of 200 reference points for each region of the case study. The reference data was collected with total station survey. The results showed that the accuracies for the prepared DEMs are suitable for some certain engineering applications but inadequate to meet the standard required for fine/small scale DEM for very precise engineering study. The obtained accuracies for terrain with small height difference can be used for preparing large area cadastral, city planning, or land classification maps. In general, Google Earth elevation data can be used only for investigation and preliminary studies with low cost. It is strongly concluded that the users of Google Earth have to test the accuracy of elevation data by comparing with reference data before using it.

15

Numeryczny model terenu jako źródło danych w prowadzeniu prac projektowych oraz metody jego wizualizacji

Kwoczyńska B., Maciejasz A.

Archiwum Fotogrametrii, Kartografii i Teledetekcji

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2004

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Vol. 15

139--144

PL

Numeryczny model opisuje powierzchnię terenu za pomocą zbioru punktów (x,y,z) i jest 011oparty najczęściej na regularnej siatce kwadratów bądź też nieregularnej siatce trójkątów. Wielkość siatki numerycznego modelu dobierana jest w zależności od właściwości geometrycznych terenu oraz tak , aby dokładność wysokościowa NMT była 1/20 (dla terenu łatwego) i 1/10 (dla terenu trudnego) wymiaru terenowego siatki. W pracy przedstawiono zastosowanie Numerycznego Modelu Terenu w różnorodnych pracach projektowych oraz możliwości jego wizualizacji w grafice trójwymiarowej.

EN

Digital terrain model (DTM) describes terrain surface with the help o f the set of points (x, y,z). It is often founded on regular net o f squares or irregular net o f triangles. The choice of DTM net size depends on geometrical properties o f the terrain and also on condition that height accuracy o f DTM should be l/20th (for an easy terrain) or 1/10th (for difficult terrain) o f actual net size. The paper shows the application o f DTM to different projects and the possibilities os its visualization in 3-dimensional graphics.

16

AIgorithms for automatically detecting and filtering ground covered objects for exact generation of DEM

Chinh Ke L.

Geodezja i Kartografia

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2002

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T. 51, z. 3

141-152

EN

Automatic generation of DEM based on image matching technique is an important part in digital photogrammetry. DEM has been found widely in practical applications as in the fields of surveying, civil engineering, road design, agriculture, military, ete. For large DEM project, accuracy, efficiency, and eeonomy are the three main factors to be taken into account. Accuracy is the first important factor to be considered. The effeet of modeling methods on DEM accuracy have been tested. The charaeteristics of terrain surface are considered as a difficult and traditional topic in generating of DEM. Terrain surface may be open or covered with different objects. For generation of accurate DEM, objects on terrain surface must be detected and filtered. There are many methods for detecting and filtering objects which have been found on the terrain surface. Some of them are basing on mutual location of measured points along definite profiles (geometric analysis) or on images converted. This artic1e presents formulas for automatically detecting and filtering covered objects on the base of the geometric analysis of measured points mutually located along determined profiles in X and Y-direction.

PL

Automatyczne generowanie cyfrowego modelu wysokościowego DEM (Digital Elevation Model) opierające o technikę dopasowania obrazów (image matching) jest jednym z głównych zadań w fotogrametrii cyfrowej. DEM ma szerokie zastosowania w różnych dziedzinach jak w projektach inżynierskich, rolnictwie, wojskowej operacji itd. Trzy główne czynniki, które należy oddać do oceny przy analizie jakości generowania DEM są to dokładność, efektywność i ekonomiczność. Dokładność DEM jest pierwszym czynnikiem ważnym oddanym do analizy. Na dokładność generowania DEM wpływają dokładność źródłowych danych, rozmiary siatki regularnej stosowanej do interpretacji, charakterystyki powierzchni terenu i metoda modelowania. Charakterystyki terenu są rozważane jako tradycyjnie trudnym tematem w generowaniu DEM. Dla dokładnego utworzenia DEM, obiekty pokrywające teren jak budynki, drzewa, itd. powinien być detekcyjne i filtracyjne. W niniejszym artykule przedstawia się algorytmy do automatycznej detekcji i filtracji obiektów wystających ponad teren dla dokładnego wygenerowania DEM, basując na geometrycznej analizie pomierzonych punktów siatki wzdłuż określonego profilu w kierunku X i Y.