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1
Levin, Eugene, Roman Shults, Reza Habibi, Zhongming An, and William Roland. "Geospatial Virtual Reality for Cyberlearning in the Field of Topographic Surveying: Moving Towards a Cost-Effective Mobile Solution." ISPRS International Journal of Geo-Information 9, no. 7 (July 10, 2020): 433. http://dx.doi.org/10.3390/ijgi9070433.
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In spite of the tremendous success in artificial intelligence technology and a high level of automation in geospatial data obtaining processes, there is still a need for topographical field data collection by professional surveyors. Understanding terrain topology and topography is a cognitive skill set that has to be demonstrated by geospatial Subject Matter Experts (SME) for the productive work in the topographic surveying field. For training of the mentioned above skillset, one has to be exposed to the theory and must also practice with surveying instruments in field conditions. The challenge of any surveying/geospatial engineering workforce training is to expose students to field conditions which might be limited due to equipment expenses and meteorological conditions that prevent good data collection. To meet this challenge, the Integrated Geospatial Technology research group is working on a geospatial virtual reality (VR) project which encompasses the following components: (a) immersive visualization of terrain; (b) virtual total station instrument; (c) virtual surveyor with reflector installed on the virtual rod. The application scenario of the technology we are working with has the following stages: (1) student is installing total station on the optimal location; (2) students move virtual surveyor on the sampling points they consider to be important (3) contours are generated and displayed in 3D being superimposed on 3D terrain; (4) accuracy of terrain modeling is observable and measurable by comparing the sampling model with initial one.
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Senciales-González, J. M., J. Rodrigo-Comino, and P. Smith. "Surveying topographical changes and climate variations to detect the urban heat island in the city of Málaga (Spain)." Cuadernos de Investigación Geográfica 46, no. 2 (September 15, 2020): 521–43. http://dx.doi.org/10.18172/cig.4228.
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The main aim of this research was to detect a possible urban heat island (UHI) in the tourist city of Málaga (Spain). To achieve this goal, different methods to validate annual and monthly temperature data have been used, and the internal variability of the UHI with respect to the topographical changes was also surveyed. Our results showed two types of atmospheric thermal gradients: one characterized by a positive gradient according to an elevation above sea level, and another with a negative gradient related to rural areas. The maximum impact of the UHI was found to be 9.1 ºC for an instantaneous event, 4.4 ºC for daily minimum temperatures in August, with a maximum weighted average difference of 2.3 ºC between data from urban and rural stations. We conclude that the detection of UHI is useful as a tool to help urban planners, in order to reduce the intensity of possible climate changes in cities. It is also concluded that UHI is not only a meteorological phenomenon in Málaga city but a climatic phenomenon, present during most days and across the transect of increasing intensity from the sea to the city.
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Wang, Yun, Z. Y. Xu, Y. H. Fu, and Lan Cai. "Investigation into LST and its Novel Application in Mould." Advanced Materials Research 24-25 (September 2007): 189–94. http://dx.doi.org/10.4028/www.scientific.net/amr.24-25.189.
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Laser surface texturing (LST) technology that is firstly used in rollers, is a specialized surface engineering process capable of enhancing the surface material properties, wear resistance, fretting fatigue life and reducing friction. This practical technology of the LST process is based on a pulsating laser beam that, by material ablation, generates the optimum topographical surface. In order to exploit the full potential of the process, a great amount of research has explored from the material removal mechanics to the development of the LST process. This paper reports on the LST research involving the LST technology surveying process optimization, LST equipment and its industrial applications. The paper also highlights the forming theory describing the skin-pass process of transferring the textured roller’s surface structure onto the steel sheet, and the laser-matter interaction that occurs when and intense laser beam is tightly focused in the workpiece surface. It presents the influence of various factors affecting the textured workpiece performance together with the investigations into tribology of textured components. The paper also discusses these developments and some fundamental on future LST research.
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Mackovčin, Peter, and Martin Jurek. "New facts about old maps of the territory of the former Czechoslovakia." Geografie 120, no. 4 (2015): 489–506. http://dx.doi.org/10.37040/geografie2015120040489.
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The authors have searched the archives for information concerning the large-scale mapping of Czechoslovakia in the period 1921–1950, when the improvement and updating of older maps inherited from the Austro-Hungarian Monarchy was carried out and new large-scale mapping was launched. Several map sets resulted from the mapping, yet they did not cover the whole territory of Czechoslovakia. Among the sets are: Czechoslovak revised topographical sections of the Austrian 3rd Military Survey, Czechoslovak preliminary maps in Beneš projection, Czechoslovak definitive maps in Křovák projection, German maps to the scale 1:25,000 called “Sonderausgabe” (Special Edition), “Karte des Sudetenlandes” (Map of Sudetenland), “Karte der Slowakei” (Map of Slovakia), and “Messtischblätter” surveyed during WWII. According to the authors’ research these maps covered 69.4% of the territory of Czechoslovakia as it was in 1938 and 75.6% of its territory in 1950. Surveying methods had improved over time and included the use of aerial photography.
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Dogon-yaro, M. A., P. Kumar, A. Abdul Rahman, and G. Buyuksalih. "EXTRACTION OF URBAN TREES FROM INTEGRATED AIRBORNE BASED DIGITAL IMAGE AND LIDAR POINT CLOUD DATASETS - INITIAL RESULTS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W1 (October 26, 2016): 81–88. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w1-81-2016.
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Timely and accurate acquisition of information on the condition and structural changes of urban trees serves as a tool for decision makers to better appreciate urban ecosystems and their numerous values which are critical to building up strategies for sustainable development. The conventional techniques used for extracting tree features include; ground surveying and interpretation of the aerial photography. However, these techniques are associated with some constraint, such as labour intensive field work, a lot of financial requirement, influences by weather condition and topographical covers which can be overcome by means of integrated airborne based LiDAR and very high resolution digital image datasets. This study presented a semi-automated approach for extracting urban trees from integrated airborne based LIDAR and multispectral digital image datasets over Istanbul city of Turkey. The above scheme includes detection and extraction of shadow free vegetation features based on spectral properties of digital images using shadow index and NDVI techniques and automated extraction of 3D information about vegetation features from the integrated processing of shadow free vegetation image and LiDAR point cloud datasets. The ability of the developed algorithms shows a promising result as an automated and cost effective approach to estimating and delineated 3D information of urban trees. The research also proved that integrated datasets is a suitable technology and a viable source of information for city managers to be used in urban trees management.
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Garcia-León, Josefina, María Milagrosa Ros-Sala, Antonio García Martín, Manuel Torres Picazo, Felipe Cerezo Andreo, and Sebastián F. Ramallo Asensio. "Reconstrucción virtual paleotopográfixca de la ciudad histórica de Cartagena (España)." Virtual Archaeology Review 8, no. 16 (May 22, 2017): 61. http://dx.doi.org/10.4995/var.2017.5836.
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The city of Cartagena and its immediate surroundings have experienced significant topographical changes throughout its history. Originally built on five hills which border south and west with the Mediterranean Sea, the city has expanded to the north over the last five decades, occupying a lacustrine system which has now dried up due to the diversion of riverbeds which, from time to time, used to flood the place. These changes have been documented and studied from the lithology present in over 400 geotechnical drillings carried out in the urban renewal of the city for the last two decades. In addition, another 20 new continuous drillings have been conducted within the Project “Surveying and planning a privileged Mediterranean city, Arqueotopos I and II” which is still ongoing. The information obtained is completed with the study of all existing historical maps on it. Digital Terrain Models (DTMs) have been generated with this drilling data, then several lithological layers have been selected for its interest: anthropic fill, mud and underlying bedrock. The thickness of each of the layers has been studied in different areas and viewed through various longitudinal profiles that have been plotted. Finally, a three-dimensional (3D) virtual reconstruction has been undertaken to see graphically the documented changes that have occurred in each of these layers, to serve both research and divulgation knowledge.
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Ahmed, Asif, MD Sahadat Hossain, Pratibha Pandey, Anuja Sapkota, and Boon Thian. "Deformation Modeling of Flexible Pavement in Expansive Subgrade in Texas." Geosciences 9, no. 10 (October 18, 2019): 446. http://dx.doi.org/10.3390/geosciences9100446.
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The tendency of expansive subgrade soil to undergo swelling and shrinkage with the change in moisture has a significant impact on the performance of the pavement. The repeated cycles of wet and dry periods throughout a year lead to considerable stress concentration in the pavement subgrade soil. Such stress concentrations leads to the formation of severe pavement cracks. The objective of the research is to develop a prediction model to estimate the deformation of pavement over expansive subgrade. Two pavement sites—one farm to market road and one state highway—were monitored regularly using moisture and temperature sensors along with rain gauges. Additionally, geophysical testing was performed to obtain a continuous profile of the subgrade soil over time. Topographical surveying and horizontal inclinometer readings were taken to determine pavement deformation. The field monitoring data resulted in a maximum movement up to 80 mm in the farm to market road, and almost 38 mm in the state highway. The field data were statistically evaluated to develop a deformation prediction model. The validation of the model indicated that only a fraction of the deformation was reflected by seasonal variation, while inclusion of rainfall events in the equation significantly improved the model. Furthermore, the prediction model also incorporated the effects of change in temperature and resistivity values. The generated model could find its application in predicting pavement deformation with respect to rainfall at any time of the year.
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Gao, Z., Y. Song, C. Li, F. Zeng, and F. Wang. "RESEARCH ON THE APPLICATION OF RAPID SURVEYING AND MAPPING FOR LARGE SCARE TOPOGRAPHIC MAP BY UAV AERIAL PHOTOGRAPHY SYSTEM." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W6 (August 23, 2017): 121–25. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w6-121-2017.
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Rapid acquisition and processing method of large scale topographic map data, which relies on the Unmanned Aerial Vehicle (UAV) low-altitude aerial photogrammetry system, is studied in this paper, elaborating the main work flow. Key technologies of UAV photograph mapping is also studied, developing a rapid mapping system based on electronic plate mapping system, thus changing the traditional mapping mode and greatly improving the efficiency of the mapping. Production test and achievement precision evaluation of Digital Orth photo Map (DOM), Digital Line Graphic (DLG) and other digital production were carried out combined with the city basic topographic map update project, which provides a new techniques for large scale rapid surveying and has obvious technical advantage and good application prospect.
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Liu, Shao Tang, Xi Rui Liu, and Fu Qin Yang. "Control Surveying and Structural Health Monitoring Applied in Large Bridge." Advanced Materials Research 639-640 (January 2013): 243–46. http://dx.doi.org/10.4028/www.scientific.net/amr.639-640.243.
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In order to ensure the safety of the bridge, Control surveying and monitoring was applied in many ways. This paper introduces the surveying and monitoring methods, analyzes the surveying accuracy, discuses the effective measures. In case study, Trimble 5700 GPS, TPS，Levels were used to perform the control surveying, and video camera, camera, georobot, three-dimensional laser scanner and other graph or image sensors were used to monitor bridge deformation. The research shows that the relative error of the control network baseline is smaller than 10-6 and the elevation accuracy is satisfied with the standard. The control survey enabled all surveying, mapping and monitoring activities to share a common geodetic reference system，provided a reliable support for the monitoring of the piers，box girders，coastal topographic details as well as hydrographic activities. And the application of modern sensors and the data acquisition technology reflected the real-time deformation conditions of bridge and provided forecasting and alarming information at any time by ways of number, curves, graph and image with high efficiency.
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Cheng, Yihan, Xin Yang, and Hailong Liu. "DEM based Terrain Sketch Mapping in a Loess Landform by considering visual hierarchy and feature generalization." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-43-2019.
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<p><strong>Abstract.</strong> A terrain sketch map can effectively describe the terrain features and spatial pattern of a landscape, which are sketched with lines by a geographer after recognizing, analyzing and summarizing the features of a terrain scene to present his/her understanding of a landscape (Bao 1956, Chen 1958, Liu 1988). Compared with a digital elevation model (DEM) scene map, a terrain sketch map, as a scientific abstraction and expression of geomorphological features from the perspective view, is characterized by conciseness and profoundness to show the intrinsic features of a landscape. With the rapid development of computer visualization and digital terrain analysis methods, computer-assisted terrain sketches based on DEM may be automatically generated, depending on geographic cognition theory and the sketch description method.</p><p> Previous research has generated terrain scene maps based on DEM data and has produced various styles of terrain maps, i.e. oil painting, ink painting, pen and pencil sketch maps (Visvalingam et al. 1998, Whelan et al. 2003, Way et al. 2006, Bhattacharjee et al. 2008). However, those computer-drawn sketch maps have focused on the artistic effect rather than depicting terrain features and landform structures. Moreover, the area used for sketch mapping in those researches was relatively small, and visual hierarchy was not considered. Thus, those maps differ considerably from hand-drawn sketch maps by geographers or geologists. Therefore, this paper aims to generate terrain sketch map which can express terrain features as well as artistic effect.</p><p> In this study, one loess ridge-hill area (Wuqi) in the loess plateau of China was selected by considering the typicality of the geomorphic types and the availability of data. The 5&thinsp;m resolution DEM data was obtained from the National Administration of Surveying, Mapping and Geoinformation, with an area of 102&thinsp;km<sup>2</sup>.</p><p> Three aspects as terrain features, visual hierarchy and feature generalization were considered in this paper.</p><p> Firstly, the typical terrain features must be presented in the sketch map. The loess shoulder line, bank gully lines and surface flow lines in loess landform area were extracted (Yang et al. 2017, Yang et al. 2018). Then based on the Bresenham algorithm (Bresenham 1965), the visual outlines in perspective view were generated.</p><p> Secondly, the visual hierarchy is considered in this study. In a terrain sketch map, more topographically-detailed information is described in the near view, whereas only the approximate outlines and less topographical information are displayed in the distant view. Therefore, a self-adapted visual hierarchy division method was proposed. The scenes are visually divided into three levels, i.e. near view, medium view and distant view. Different numbers and types of terrain features are assigned to each visual level to obtain the effect of clear near and blurred distant views.</p><p> Thirdly, in complexity terrain area, the scene will not only look staggered and messy, but will also affect topographic recognition even only visual outlines are displayed in distant view. Therefore a method of combining DEM and visual watershed generalization was proposed to simplify the visual outlines in distant view.</p><p> Finally, the terrain sketch map is assessed and verified through a questionnaire survey which includes three specialist experts, seven graduate students and twelve undergraduate students with knowledge in geomorphology or geography.</p><p> The result show that the important feature lines added to the terrain sketch map could effectively help to recognize the typical landform characteristics in the loess plateau of China. The severity of soil erosion by gullies are obviuosly presented (Fig.1d) comparing to the sketch mapping with only visual outlines (Fig1b). The map look messy and unsigtly if all the terrain feature lines were put into the map (Fig.1c). By considering the law of air perspective, the visual hierarchy was divided and the visual outlines in the distant view was generalized, thereby realizing the characteristics of a terrain sketch map clear in near view and blurred in distant view (Fig.1d). It also showed from the questionnaire that DEM resolution influence the performance of our method especially with coarse resolution DEM. The experts suggested that filter noise in near view and generalisation in distant view can be further improved.</p>
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Han, You Mei, and Bo Gang Yang. "A Efficient Method to Map Large Scale Topographic Maps with Vehicle-Borne Lidar System." Applied Mechanics and Materials 373-375 (August 2013): 2057–60. http://dx.doi.org/10.4028/www.scientific.net/amm.373-375.2057.
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Recent years, the vehicle-borne LIDAR technology has a rapid development, and its application in surveying and mapping is becoming a hot research topic. The main objective of this investigation is to explore the potential of vehicle-borne LIDAR technology to be used to fast mapping large scale topographic maps based on new Chinese vehicle-borne LIDAR system. It studied how to use the new Chinese vehicle-borne LIDAR system measurement technology to map large scale topographic maps. After the field data capture, it can be mapped in the office based on the LIDAR data (point cloud) by special software which programmed by ourselves. In addition, the detailed process and accuracy analysis were proposed by an actual case. The result revealed this new technology provides a new fast method to map large scale topographic maps, which is high efficient and accuracy compared to the traditional methods.
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Park, Sebeom, and Yosoon Choi. "Applications of Unmanned Aerial Vehicles in Mining from Exploration to Reclamation: A Review." Minerals 10, no. 8 (July 26, 2020): 663. http://dx.doi.org/10.3390/min10080663.
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Over the past decade, unmanned aerial vehicles (UAVs) have been used in the mining industry for various applications from mineral exploration to mine reclamation. This study aims to review academic papers on the applications of UAVs in mining by classifying the mining process into three phases: exploration, exploitation, and reclamation. Systematic reviews were performed to summarize the results of 65 articles (June 2010 to May 2020) and outline the research trend for applying UAVs in mining. This study found that UAVs are used at mining sites for geological and structural analysis via remote sensing, aerial geophysical survey, topographic surveying, rock slope analysis, working environment analysis, underground surveying, and monitoring of soil, water, ecological restoration, and ground subsidence. This study contributes to the classification of current UAV applications during the mining process as well as the identification of prevalent UAV types, data acquired by sensors, scales of targeted areas, and styles of flying control for the applications of UAVs in mining.
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Stopková, Eva. "Geodetic work at the archaeological site Tell el-Retaba." Geoinformatics FCE CTU 17, no. 2 (August 23, 2018): 65–80. http://dx.doi.org/10.14311/gi.17.2.4.
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The paper summarizes the geodetic contribution for the Slovak team within the joint Polish-Slovak archaeological mission at Tell el-Retaba in Egypt. Surveying work at archaeological excavations is usually influenced by somewhat specific subject of study and extreme conditions, especially at the missions in the developing countries. The case study describes spatial data development according to the archaeological conventions in order to document spatial relationships between the objects in excavated trenches. The long-term sustainability of surveying work at the site has been ensured by detailed metadata recording. Except the trench mapping, Digital Elevation Model has been calculated for the study area and for the north-eastern part of the site, with promising preliminary results for further detection and modelling of archaeological structures. In general, topographic mapping together with modern technologies like Photogrammetry, Satellite Imagery, and Remote Sensing provide valuable data sources for spatial and statistical modelling of the sites; and the results offer a different perspective for the archaeological research.
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Chaudhry, Muhammad Hamid, Anuar Ahmad, and Qudsia Gulzar. "Impact of UAV Surveying Parameters on Mixed Urban Landuse Surface Modelling." ISPRS International Journal of Geo-Information 9, no. 11 (October 31, 2020): 656. http://dx.doi.org/10.3390/ijgi9110656.
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Unmanned Aerial Vehicles (UAVs) as a surveying tool are mainly characterized by a large amount of data and high computational cost. This research investigates the use of a small amount of data with less computational cost for more accurate three-dimensional (3D) photogrammetric products by manipulating UAV surveying parameters such as flight lines pattern and image overlap percentages. Sixteen photogrammetric projects with perpendicular flight plans and a variation of 55% to 85% side and forward overlap were processed in Pix4DMapper. For UAV data georeferencing and accuracy assessment, 10 Ground Control Points (GCPs) and 18 Check Points (CPs) were used. Comparative analysis was done by incorporating the median of tie points, the number of 3D point cloud, horizontal/vertical Root Mean Square Error (RMSE), and large-scale topographic variations. The results show that an increased forward overlap also increases the median of the tie points, and an increase in both side and forward overlap results in the increased number of point clouds. The horizontal accuracy of 16 projects varies from ±0.13m to ±0.17m whereas the vertical accuracy varies from ± 0.09 m to ± 0.32 m. However, the lowest vertical RMSE value was not for highest overlap percentage. The tradeoff among UAV surveying parameters can result in high accuracy products with less computational cost.
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Khlebnikova, Tatyana A. "RESEARCH AND TECHNOLOGY DEVELOPMENT FOR CONSTRUCTION OF 3D VIDEO SCENES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-6 (June 6, 2016): 23–27. http://dx.doi.org/10.5194/isprsannals-iii-6-23-2016.
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For the last two decades surface information in the form of conventional digital and analogue topographic maps has been being supplemented by new digital geospatial products, also known as 3D models of real objects. It is shown that currently there are no defined standards for 3D scenes construction technologies that could be used by Russian surveying and cartographic enterprises. The issues regarding source data requirements, their capture and transferring to create 3D scenes have not been defined yet. The accuracy issues for 3D video scenes used for measuring purposes can hardly ever be found in publications. Practicability of development, research and implementation of technology for construction of 3D video scenes is substantiated by 3D video scene capability to expand the field of data analysis application for environmental monitoring, urban planning, and managerial decision problems. The technology for construction of 3D video scenes with regard to the specified metric requirements is offered. Technique and methodological background are recommended for this technology used to construct 3D video scenes based on DTM, which were created by satellite and aerial survey data. The results of accuracy estimation of 3D video scenes are presented.
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Khlebnikova, Tatyana A. "RESEARCH AND TECHNOLOGY DEVELOPMENT FOR CONSTRUCTION OF 3D VIDEO SCENES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences III-6 (June 6, 2016): 23–27. http://dx.doi.org/10.5194/isprs-annals-iii-6-23-2016.
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For the last two decades surface information in the form of conventional digital and analogue topographic maps has been being supplemented by new digital geospatial products, also known as 3D models of real objects. It is shown that currently there are no defined standards for 3D scenes construction technologies that could be used by Russian surveying and cartographic enterprises. The issues regarding source data requirements, their capture and transferring to create 3D scenes have not been defined yet. The accuracy issues for 3D video scenes used for measuring purposes can hardly ever be found in publications. Practicability of development, research and implementation of technology for construction of 3D video scenes is substantiated by 3D video scene capability to expand the field of data analysis application for environmental monitoring, urban planning, and managerial decision problems. The technology for construction of 3D video scenes with regard to the specified metric requirements is offered. Technique and methodological background are recommended for this technology used to construct 3D video scenes based on DTM, which were created by satellite and aerial survey data. The results of accuracy estimation of 3D video scenes are presented.
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Smith, R., and J. Byrd. "Earthquake Hazards of Grand Teton National Park Emphasizing the Teton Fault." UW National Parks Service Research Station Annual Reports 13 (January 1, 1989): 140–46. http://dx.doi.org/10.13001/uwnpsrc.1989.2811.
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This is a progress report on the research of the University of Utah project: "Earthquake Hazards of The Grand Teton National Park Emphasizing The Teton Fault", to date, 31 December, 1989. The research objectives during 1989 focussed on: 1) excavation of a trench across the Teton fault to determine the age and amount of displacement associated with prehistoric ground breaking earthquakes; 2) collection of paleomagnetic samples of Huckleberry Ridge tuff along an E-W transect across the northern end of the Teton range to assess deformation associated with the Teton fault; 3) mapping and surveying of two study areas along the fault to evaluate the geomorphic expression of the fault; 4) surveying a detailed topographic and gravity profile across the valley from String Lake to the Snake River to evaluate deformation of the valley floor and to help constrain modeling of the subsurface fault geometry, 5) continuing the study of expected fault motion of the Teton fault based on our previous results, 6) mapping of the northern extent of the Teton fault zone, and 7) assisting the NPS with interpretations and use of our data for management and interpretational purposes.
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Xiong, Lin, Guoquan Wang, Yan Bao, Xin Zhou, Kuan Wang, Hanlin Liu, Xiaohan Sun, and Ruibin Zhao. "A Rapid Terrestrial Laser Scanning Method for Coastal Erosion Studies: A Case Study at Freeport, Texas, USA." Sensors 19, no. 15 (July 24, 2019): 3252. http://dx.doi.org/10.3390/s19153252.
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Terrestrial laser scanning (TLS) has become a powerful data acquisition technique for high-resolution high-accuracy topographic and morphological studies. Conventional static TLS surveys require setting up numerous reflectors (tie points) in the field for point clouds registration and georeferencing. To reduce surveying time and simplify field operational tasks, we have developed a rapid TLS surveying method that requires only one reflector in the field. The method allows direct georeferencing of point clouds from individual scans to an East–North–Height (ENH) coordinate system tied to a stable geodetic reference frame. TLS datasets collected at a segment of the beach–dune–wetland area in Freeport, Texas, USA are used to evaluate the performance of the rapid surveying method by comparing with kinematic GPS measurements. The rapid surveying method uses two GPS units mounted on the scanner and a reflector for calculating the northing angle of the scanner’s own coordinate system (SOCS). The Online Positioning User Service (OPUS) is recommended for GPS data processing. According to this study, OPUS Rapid-Static (OPUS-RS) solutions retain 1–2 cm root mean square (RMS) accuracy in the horizontal directions and 2–3 cm accuracy in the vertical direction for static observational sessions of approximately 30 min in the coastal region of Texas, USA. The rapid TLS surveys can achieve an elevation accuracy (RMS) of approximately 3–5 cm for georeferenced points and 2–3 cm for digital elevation models (DEMs). The elevation errors superimposed into the TLS surveying points roughly fit a normal distribution. The proposed TLS surveying method is particularly useful for morphological mapping over time in coastal regions, where strong wind and soft sand prohibit reflectors from remaining strictly stable for a long period. The theories and results presented in this paper are beneficial to researchers who frequently utilize TLS datasets in their research, but do not have opportunities to be involved in field data acquisition.
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Habib, Maan, Yazan Alzubi, Ahmad Malkawi, and Mohammad Awwad. "Impact of interpolation techniques on the accuracy of large-scale digital elevation model." Open Geosciences 12, no. 1 (July 3, 2020): 190–202. http://dx.doi.org/10.1515/geo-2020-0012.
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AbstractThere is no doubt that the tremendous development of information technology was one of the driving factors behind the great growth of surveying and geodesy science. This has spawned modern geospatial techniques for data capturing, acquisition, and visualization tools. Digital elevation model (DEM) is the 3D depiction of continuous elevation data over the Earth’s surface that is produced through many procedures such as remote sensing, photogrammetry, and land surveying. DEMs are essential for various surveying and civil engineering applications to generate topographic maps for construction projects at a scale that varies from 1:500 to 1:2,000. GIS offers a powerful tool to create a DEM with high resolution from accurate land survey measurements using interpolation methods. The aim of this research is to investigate the impact of estimation techniques on generating a reliable and accurate DEM suitable for large-scale mapping. As a part of this study, the deterministic interpolation algorithms such as ANUDEM (Topo to Raster), inverse distance weighted (IDW), and triangulated irregular network (TIN) were tested using the ArcGIS desktop for elevation data obtained from real total station readings, with different landforms to show the effect of terrain roughness, data density, and interpolation process on DEM accuracy. Furthermore, comparison and validation of each interpolator were carried out through the cross-validation method and numerous graphical representations of the DEM. Finally, the results of the investigations showed that ANUDEM and TIN models are similar and significantly better than those attained from IDW.
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Jianming, Chen. "Map of the Mount Gongga Glacier: A Combination of Terrestrial and Aerial Photogrammetry." Annals of Glaciology 8 (1986): 34–36. http://dx.doi.org/10.1017/s0260305500001099.
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For use in glaciological research, between 1982 and 1984, we succeeded in surveying and mapping the Mount Gongga Glacier, on a scale of 1:25 000, by means of a combination of terrestrial and aerial photogrammetry. This paper describes the method in detail. In the survey area, we set up an independent, triangulation network, with microwave distance measurement, and two, independent, straight-line traverses, for basic control. Control points were observed by intersection. The terrestrial, photogrammetric baselines were projected and corrected into distances on the. plane of the map. Terrestrial photography accounted for the majority of the photographs of the survey area. Surveying and mapping of planimetrie and topographic features were completed on a stereo-autograph, using plates mainly from terrestrial photogrammetry. Where these data were insufficient, they were supplemented by aerial photography, plotted on a photographic plotting instrument. Orientation points of the aerial photographs were established by terrestrial, photogrammetric analysis and located on the map by an optical, mechanical method. The practical result showed that a combination of terrestrial and aerial photogrammetry, in mapping a high, mountain, glacier area, on a large scale, is more feasible and flexible than other methods and more economical as well.
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Jianming, Chen. "Map of the Mount Gongga Glacier: A Combination of Terrestrial and Aerial Photogrammetry." Annals of Glaciology 8 (1986): 34–36. http://dx.doi.org/10.3189/s0260305500001099.
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For use in glaciological research, between 1982 and 1984, we succeeded in surveying and mapping the Mount Gongga Glacier, on a scale of 1:25 000, by means of a combination of terrestrial and aerial photogrammetry. This paper describes the method in detail.In the survey area, we set up an independent, triangulation network, with microwave distance measurement, and two, independent, straight-line traverses, for basic control. Control points were observed by intersection. The terrestrial, photogrammetric baselines were projected and corrected into distances on the. plane of the map.Terrestrial photography accounted for the majority of the photographs of the survey area. Surveying and mapping of planimetrie and topographic features were completed on a stereo-autograph, using plates mainly from terrestrial photogrammetry. Where these data were insufficient, they were supplemented by aerial photography, plotted on a photographic plotting instrument. Orientation points of the aerial photographs were established by terrestrial, photogrammetric analysis and located on the map by an optical, mechanical method.The practical result showed that a combination of terrestrial and aerial photogrammetry, in mapping a high, mountain, glacier area, on a large scale, is more feasible and flexible than other methods and more economical as well.
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Choo, Yeon-Moon, Ji-Min Kim, and Ik-Tae An. "Research on the Longitudinal Section of River Restoration Using Probabilistic Theory." Entropy 23, no. 8 (July 27, 2021): 965. http://dx.doi.org/10.3390/e23080965.
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Since the 1960s, many rivers have been destroyed as a consequence of the process of rapid urbanization. As accurate figures are important to repair rivers, there have been many research reports on methods to obtain the exact river slope and elevation. Until now, many research efforts have analyzed the river using measured river topographic factors, but when the flow velocity changes rapidly, such as during a flood, surveying is not easy; and due to cost, frequent measurements are difficult. Previous research has focused on the cross section of the river, so the information on the river longitudinal profile is insufficient. In this research, using informational entropy theory, equations are presented that can calculate the average river slope, river slope, and river longitudinal elevation for a river basin in real time. The applicability was analyzed through a comparison with the measured data of river characteristic factors obtained from the river plan. The parameters were calculated using informational entropy theory and nonlinear regression analysis using actual data, and then the longitudinal elevation entropy equation for each river and the average river slope were calculated. As a result of analyzing the applicability of the equations presented in this study by R2 and Root Mean Square Error, all R2 values were over 0.80, while RMSE values were analyzed to be between 0.54 and 2.79. Valid results can be obtained by calculating river characteristic factors.
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Altyntsev, M. A., and K. H. Majeed Saber. "THE STUDY OF MOBILE LASER SCANNING DATA ADJUSTMENT RESULTS FOR LARGE SCALE TOPOGRAPHIC MAPPING." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2020 (August 12, 2020): 197–203. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2020-197-2020.
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Abstract. Mobile laser scanning (MLS) data are widely used for solving various tasks. To be sure that these data are appropriate for a specific task it is necessary to adjust data with a certain accuracy. Large scale topographic mapping is one from the tasks often solved by MLS data. Necessary accuracy of creating topographic plans is determined with a requirements document. Topographic plans are always created in a certain coordinate system. For this reason, MLS data should be previously transformed in the required one. For transformation control points measured with other more accurate methods should be applied. The quantity of necessary control points depends on a surveying area. For urban areas a lot of control points are required due to bad quality of GNSS signal. Much research has been conducted for these areas. For areas with open view of the sky it is required significantly fewer control points. Moreover, there are not so many vertical objects in areas with open view of the sky. Large errors can take place in the result of automatic adjustment of point cloud’s multi-passes. The results of both relative and absolute MLS data adjustment are given for the area with a good GNSS signal. The paper presents the results of accuracy estimation with different quantity of control points. The main goal of the paper is to determine the minimum number of control points for MLS data to be appropriate for creating topographic plans at a scale of 1:500 with a contour interval of 0.25 m.
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Celms, Armands, Velta Parsova, Ilona Reke, and Janis Akmentins. "Tendencies of development of local geodetic network in Riga city." Baltic Surveying 9 (December 5, 2018): 8–15. http://dx.doi.org/10.22616/j.balticsurveying.2018.013.
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Local geodetic network is very important in harmonic development of city territory. On the base of the local geodetic network, cadastral and topographic surveying works, engineering geodetic works and executive measurements of newly built buildings and engineering networks are carried out. In the territory of Riga, the local geodetic network was started to create in 1880, and in the course of time, as the city expanded, necessity to have wider reference network emerged. In 2005, in the territory of Latvia, network of continuously working base stations LatPos was launched, which ensured completely new trends in execution of measurements and accuracy reached. One year later, base station network EUPOS-RIGA was launched in the territory of Riga. It can be regarded as consistent part of Riga local geodetic network. The purpose of the research was to state, what are differences between historically used coordinates of points of the local geodetic network, and coordinates that are determined by use of real time corrections of LatPos and EUPOS-RIGA base station network. Measurements were made in the territory of Riga in period from December 2016 until April 2017. In the framework of the research, 61 point of the local geodetic network was inspected and in 38 cases GNSS observations in RTK mode were completed. In the research, catalogues of coordinates of polygonometry points of sixties and eighties were used in order to compare what differences of coordinates existed historically. The main conclusion drawn during the research – historical points of the local geodetic network shall not be used for surveying works of any kind before improvement of them and before they comply with requirements of normative acts.
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Shanurov, G. A., and A. D. Manilova. "Mobile scanning complex positioning accuracy depending on the coordinate systems used." Geodesy and Cartography 919, no. 1 (February 20, 2017): 13–17. http://dx.doi.org/10.22389/0016-7126-2017-919-1-13-17.
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Inertial coordinate system and geodetic (terrestrial) coordinate system are used in processing of results of topographic survey, carried out with a mobile scanning complex. Mobile scanning complex geodetic coordinates, in turn, are presented in geodetic three-dimensional rectangular coordinate system form, in geodetic ellipsoidal coordinate system form and in the form of coordinates on a geodetic projection plane. The results of research, carried out earlier [4–7], suggest that the coordinate transformation on large areas distorts geodetic points coordinates. The article presents the results of similar investigations, but applied to a local area, limited by a mobile scanning complex surveying area. The accuracy of the mobile scanning complex coordinates is characterized by the mobile scanning complex coordinates errors cofactor matrix. It turned out that the local site sequential coordinate transformation procedure from one coordinate system to another coordinate system does not introduce any distortion into the mobile scanning complex coordinates.
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Xie, Hui, Haoran Wang, Yayi Yang, Yongcan Chen, Jun Yang, Shuang Wang, and Zhaowei Liu. "Analysis of Underwater Topographic Survey of Stilling Basin Based on Unmanned Survey System." Advances in Materials Science and Engineering 2021 (April 1, 2021): 1–15. http://dx.doi.org/10.1155/2021/5514165.
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The combination of Global Positioning System-Real Time Kinematic (GPS-RTK) and depth sounder is an important technical method of modern underwater topographic survey. In this paper, the combined technology was integrated with unmanned surface vehicle (USV) technology to construct an unmanned survey system suitable for underwater topographic survey in stilling basin, and it was applied to survey the underwater topography of the stilling basin of Tingzikou hydrojunction project. Based on the surveying and mapping data and 3D model, the trend of elevation change of the stilling basin including apron, end sill, antiscour section, and river convergence section was analyzed. The results show that, for the surface outlet stilling basin of Tingzikou, after flood, the structure is complete, the boundaries are clear, the water quality is good, and there is little sediment on the surface of apron from overflow dam section to end sill. Furthermore, no obvious sediment or structural abnormality has been found in the still basin. Affected by the bedrock and cofferdam cobble gravel sediment, the elevation of the antiscour section and the downstream convergence section of the surface outlet stilling basin increased significantly. For the bottom outlet stilling basin of Tingzikou, there is large sediment within a range of 20 m∼40 m from the bottom sill and the maximum height of it reaches 2.04 m, while there is no obvious sediment or structural abnormality in the remaining region of basin. The critical sedimentation height can effectively judge the safety grade of the sedimentation height in stilling basin and provide a reliable support for assessing the overall safety of stilling basin. The application of unmanned survey technology improves the accuracy and timeliness of underwater topography and sedimentation distribution of stilling basin, which has significant application research value and promotion significance.
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Udayanga, M. K. S. C., T. D. C. Pushpakumara, and Nalin Jayarathne. "Study of the Accuracy of Sri Lankan Drone Survey Technology for Land Survey on Different Terrain Conditions." International Journal of Advanced Remote Sensing and GIS 10, no. 1 (June 12, 2021): 3463–72. http://dx.doi.org/10.23953/cloud.ijarsg.500.
Full textAbstract:
With the development of the technology, Unmanned Aerial Vehicles (UAVs) are more prominently used in construction field for surveying. Because of low time consume and easy to get data at unreachable places also. At present, large scaling topographic maps are obtaining using unmanned aerial vehicle (UAV) photogrammetry method, therefore UAV photogrammetry has replacing traditional survey method like total station. But don’t know how much accuracy it has, with comparing traditional survey methods. The accuracy may be consisting on the terrain conditions. So, it is better to check which terrain conditions have more accurate and which terrains are in very low accuracy. And also, accuracy of results may be depending on the accuracy of the topography software. Level terrain, vegetation area, build-up area and slope area were obtained during the research. Selected the Kantale sugar factory area in Sri Lanka, to understand the different terrain conditions. The results showed that the UAV results are more accurate with level terrain conditions and accuracy is low with other terrain conditions. Keywords Drone survey; Topography; UAV; Total station; RTK
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Kozmus Trajkovski, Klemen, Gašper Štebe, and Dušan Petrovič. "Visualizations of the Doblar Accumulation Basin Based on the UAV Survey." Advances in Cartography and GIScience of the ICA 1 (July 3, 2019): 1–7. http://dx.doi.org/10.5194/ica-adv-1-8-2019.
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<p><strong>Abstract.</strong> Our research is based on a large case study of Unmanned Aerial Vehicle (UAV) surveys, modelling and visualizations of the Doblar accumulation basin. The various approaches for UAV surveying of large, demanding terrain configurations, and the benefits of surveying products used as a basis for other interdisciplinary hydrological and environmental services were researched. The demanding mountainous terrain, the steep slopes and deep and narrow streams required detailed pre-planning of the survey, including the pre-survey terrain overview. The accumulation basin was emptied merely for a short period; thus, the survey was performed in unfavourable weather conditions, which included coldness, snowfall and wind. Point clouds were generated and georeferenced from the 4377 recorded photos. The dense point cloud contained approximately 222 million points in the medium setting and more than a billion in the high setting. A 3D model was built from the data. This became the basis for numerous further analyses and for the presentation using cartographic principles: a digital elevation model with a resolution of 10&thinsp;cm, an orthophoto with a resolution of 10&thinsp;cm, a 3D model draped with orthophoto, contour lines with a 1&thinsp;m interval, topographic profiles, calculations of volumes at different water levels, a flythrough, augmented reality and a video simulation of the water level changes. The model can also serve as a basis for hydraulic and environmental analysis and simulations or used for analyses of the accumulation and deposition of river material compared with previous and future surveys.</p>
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Malinverni, E. S., C. Conati Barbaro, R. Pierdicca, C. A. Bozzi, and A. N. Tassetti. "UAV SURVEYING FOR A COMPLETE MAPPING AND DOCUMENTATION OF ARCHAEOLOGICAL FINDINGS. THE EARLY NEOLITHIC SITE OF PORTONOVO." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 6, 2016): 1149–55. http://dx.doi.org/10.5194/isprsarchives-xli-b1-1149-2016.
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The huge potential of 3D digital acquisition techniques for the documentation of archaeological sites, as well as the related findings, is almost well established. In spite of the variety of available techniques, a sole documentation pipeline cannot be defined a priori because of the diversity of archaeological settings. Stratigraphic archaeological excavations, for example, require a systematic, quick and low cost 3D single-surface documentation because the nature of stratigraphic archaeology compels providing documentary evidence of any excavation phase. Only within a destructive process each single excavation cannot be identified, documented and interpreted and this implies the necessity of a re- examination of the work on field. In this context, this paper describes the methodology, carried out during the last years, to 3D document the Early Neolithic site of Portonovo (Ancona, Italy) and, in particular, its latest step consisting in a photogrammetric aerial survey by means of UAV platform. It completes the previous research delivered in the same site by means of terrestrial laser scanning and close range techniques and sets out different options for further reflection in terms of site coverage, resolution and campaign cost. With the support of a topographic network and a unique reference system, the full documentation of the site is managed in order to detail each excavation phase; besides, the final output proves how the 3D digital methodology can be completely integrated with reasonable costs during the excavation and used to interpret the archaeological context. Further contribution of this work is the comparison between several acquisition techniques (i.e. terrestrial and aerial), which could be useful as decision support system for different archaeological scenarios. The main objectives of the comparison are: i) the evaluation of 3D mapping accuracy from different data sources, ii) the definition of a standard pipeline for different archaeological needs and iii) the provision of different level of detail according to the user needs.
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Malinverni, E. S., C. Conati Barbaro, R. Pierdicca, C. A. Bozzi, and A. N. Tassetti. "UAV SURVEYING FOR A COMPLETE MAPPING AND DOCUMENTATION OF ARCHAEOLOGICAL FINDINGS. THE EARLY NEOLITHIC SITE OF PORTONOVO." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 6, 2016): 1149–55. http://dx.doi.org/10.5194/isprs-archives-xli-b1-1149-2016.
Full textAbstract:
The huge potential of 3D digital acquisition techniques for the documentation of archaeological sites, as well as the related findings, is almost well established. In spite of the variety of available techniques, a sole documentation pipeline cannot be defined a priori because of the diversity of archaeological settings. Stratigraphic archaeological excavations, for example, require a systematic, quick and low cost 3D single-surface documentation because the nature of stratigraphic archaeology compels providing documentary evidence of any excavation phase. Only within a destructive process each single excavation cannot be identified, documented and interpreted and this implies the necessity of a re- examination of the work on field. In this context, this paper describes the methodology, carried out during the last years, to 3D document the Early Neolithic site of Portonovo (Ancona, Italy) and, in particular, its latest step consisting in a photogrammetric aerial survey by means of UAV platform. It completes the previous research delivered in the same site by means of terrestrial laser scanning and close range techniques and sets out different options for further reflection in terms of site coverage, resolution and campaign cost. With the support of a topographic network and a unique reference system, the full documentation of the site is managed in order to detail each excavation phase; besides, the final output proves how the 3D digital methodology can be completely integrated with reasonable costs during the excavation and used to interpret the archaeological context. Further contribution of this work is the comparison between several acquisition techniques (i.e. terrestrial and aerial), which could be useful as decision support system for different archaeological scenarios. The main objectives of the comparison are: i) the evaluation of 3D mapping accuracy from different data sources, ii) the definition of a standard pipeline for different archaeological needs and iii) the provision of different level of detail according to the user needs.
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Murillo Feo, C. A., L. J. Martnez Martinez, and N. A. Correa Muñoz. "ACCURACY AND SPATIAL VARIABILITY IN GPS SURVEYING FOR LANDSLIDE MAPPING ON ROAD INVENTORIES AT A SEMI-DETAILED SCALE: THE CASE IN COLOMBIA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (June 7, 2016): 291–97. http://dx.doi.org/10.5194/isprsarchives-xli-b2-291-2016.
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The accuracy of locating attributes on topographic surfaces when, using GPS in mountainous areas, is affected by obstacles to wave propagation. As part of this research on the semi-automatic detection of landslides, we evaluate the accuracy and spatial distribution of the horizontal error in GPS positioning in the tertiary road network of six municipalities located in mountainous areas in the department of Cauca, Colombia, using geo-referencing with GPS mapping equipment and static-fast and pseudo-kinematic methods. We obtained quality parameters for the GPS surveys with differential correction, using a post-processing method. The consolidated database underwent exploratory analyses to determine the statistical distribution, a multivariate analysis to establish relationships and partnerships between the variables, and an analysis of the spatial variability and calculus of accuracy, considering the effect of non-Gaussian distribution errors. The evaluation of the internal validity of the data provide metrics with a confidence level of 95% between 1.24 and 2.45 m in the static-fast mode and between 0.86 and 4.2 m in the pseudo-kinematic mode. The external validity had an absolute error of 4.69 m, indicating that this descriptor is more critical than precision. Based on the ASPRS standard, the scale obtained with the evaluated equipment was in the order of 1:20000, a level of detail expected in the landslide-mapping project. Modelling the spatial variability of the horizontal errors from the empirical semi-variogram analysis showed predictions errors close to the external validity of the devices.
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Murillo Feo, C. A., L. J. Martnez Martinez, and N. A. Correa Muñoz. "ACCURACY AND SPATIAL VARIABILITY IN GPS SURVEYING FOR LANDSLIDE MAPPING ON ROAD INVENTORIES AT A SEMI-DETAILED SCALE: THE CASE IN COLOMBIA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (June 7, 2016): 291–97. http://dx.doi.org/10.5194/isprs-archives-xli-b2-291-2016.
Full textAbstract:
The accuracy of locating attributes on topographic surfaces when, using GPS in mountainous areas, is affected by obstacles to wave propagation. As part of this research on the semi-automatic detection of landslides, we evaluate the accuracy and spatial distribution of the horizontal error in GPS positioning in the tertiary road network of six municipalities located in mountainous areas in the department of Cauca, Colombia, using geo-referencing with GPS mapping equipment and static-fast and pseudo-kinematic methods. We obtained quality parameters for the GPS surveys with differential correction, using a post-processing method. The consolidated database underwent exploratory analyses to determine the statistical distribution, a multivariate analysis to establish relationships and partnerships between the variables, and an analysis of the spatial variability and calculus of accuracy, considering the effect of non-Gaussian distribution errors. The evaluation of the internal validity of the data provide metrics with a confidence level of 95% between 1.24 and 2.45 m in the static-fast mode and between 0.86 and 4.2 m in the pseudo-kinematic mode. The external validity had an absolute error of 4.69 m, indicating that this descriptor is more critical than precision. Based on the ASPRS standard, the scale obtained with the evaluated equipment was in the order of 1:20000, a level of detail expected in the landslide-mapping project. Modelling the spatial variability of the horizontal errors from the empirical semi-variogram analysis showed predictions errors close to the external validity of the devices.
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Annis, Antonio, Fernando Nardi, Andrea Petroselli, Ciro Apollonio, Ettore Arcangeletti, Flavia Tauro, Claudio Belli, Roberto Bianconi, and Salvatore Grimaldi. "UAV-DEMs for Small-Scale Flood Hazard Mapping." Water 12, no. 6 (June 16, 2020): 1717. http://dx.doi.org/10.3390/w12061717.
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Devastating floods are observed every year globally from upstream mountainous to coastal regions. Increasing flood frequency and impacts affect both major rivers and their tributaries. Nonetheless, at the small-scale, the lack of distributed topographic and hydrologic data determines tributaries to be often missing in inundation modeling and mapping studies. Advances in Unmanned Aerial Vehicle (UAV) technologies and Digital Elevation Models (DEM)-based hydrologic modeling can address this crucial knowledge gap. UAVs provide very high resolution and accurate DEMs with low surveying cost and time, as compared to DEMs obtained by Light Detection and Ranging (LiDAR), satellite, or GPS field campaigns. In this work, we selected a LiDAR DEM as a benchmark for comparing the performances of a UAV and a nation-scale high-resolution DEM (TINITALY) in representing floodplain topography for flood simulations. The different DEMs were processed to provide inputs to a hydrologic-hydraulic modeling chain, including the DEM-based EBA4SUB (Event-Based Approach for Small and Ungauged Basins) hydrologic modeling framework for design hydrograph estimation in ungauged basins; the 2D hydraulic model FLO-2D for flood wave routing and hazard mapping. The results of this research provided quantitative analyses, demonstrating the consistent performances of the UAV-derived DEM in supporting affordable distributed flood extension and depth simulations.
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Anikeeva, Irina A. "FACTORS, CRITERIA AND REQUIREMENTS FOR FINE QUALITY OF AERIAL IMAGERY, OBTAINED FOR MAPPING PURPOSES." Vestnik SSUGT (Siberian State University of Geosystems and Technologies) 25, no. 4 (2020): 104–19. http://dx.doi.org/10.33764/2411-1759-2020-25-4-104-119.
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Fine image quality assessment of aerial imagery, obtained for mapping purposes, is a relevant problem today. The purpose of this article is development the criteria system of fine image quality assessment of aerial topographic imagery and set requirements to them. The article discusses a set of factors that determine the fine image quality - natural surveying conditions, its technical and technological conditions and parameters. The article carries out the analysis of how these factors influence on aerial imagery and shows the main defects of images caused by them – such as blurring, haze, loss of information in highlights and shadows, high random noise, color disbalance. The article defines the ways for identifying these defects and assessing their influence on the fine quality of aerial imagery both visual and automatic methods. It is shown that image fine quality assessment must be carried out in terms of structural and gradation (photographic) characteristics. It is also shown that, in addition to the above characteristics, fine quality of aerial images can be influenced by random factors, the appearance of which cannot be predicted. Defects caused by these factors are revealed by operator’s visual inspection. The requirements for several fine image quality criteria, which allow to establish this research phase, are given.
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Honcharenko, Oleksandr, and Bohdan Denysiuk. "EXPERIMENTAL RESEARCH OF THE ACCURACY OF NAVIGATION GNSS - RECEIVERS IN CONDITIONS OF THE CONSTRUCTED TERRITORY." Urban development and spatial planning, no. 77 (May 24, 2021): 148–59. http://dx.doi.org/10.32347/2076-815x.2021.77.148-159.
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Use of digital geodetic support technologies with the use of GNSS satellite systems in combination with electronic geodetic instruments, introduction of new methods of construction of geodetic networks, collection of information by ground and aerospace surveying, unification of exchange formats of measurement results based on computer technologies and their application conditions. Substantiation and development of remote methods of spatial information collection requires analysis and consideration of a number of errors in order to improve accuracy.
Wikimapia is a map project for shared use with open content, which aims to identify all geographical objects with the introduction of useful information about them. It combines an interactive web map and a Wiki system.
One of the features of the Wikimapia resource is that it is possible to determine geographical coordinates. To do this, you need to move the cross cursor on the object of interest and get its coordinates visually.
The purpose of the study was to determine the accuracy of the coordinates of GPS receivers Garmin Oregon 450 in the built-up area, using as a basis for calibration, the resource "Wikimapia".
In order to determine the accuracy of the location with the help of GARMIN Oregon 450 GPS receivers, GNSS measurements were performed at 30 marker points.
Ellipsoidal coordinates were recalculated into spatial rectangles according to known formulas.
In order to assess the accuracy of determining the location of marker points, the differences in the coordinates of their position were found and the root mean square error from a number of measurements was found.
The average error of coordinate measurements was ± 4.79 m for the GPS receiver.
Based on experimental research, the possibility of using the resource "Wikimapia" not only to quickly determine the coordinates of topographic objects, determine their categories, but also with sufficient accuracy to apply for the calibration of navigation GNSS receivers when there is no network of geodetic points.
A promising direction in the process of scientific and practical research should be the creation of a general mathematical model for predicting the influence of the plurality on the location and improvement of navigation aids.
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Horishnyy, Pavlo. "Geomorphological mapping of quarries." Visnyk of the Lviv University. Series Geography, no. 50 (December 28, 2016): 119–30. http://dx.doi.org/10.30970/vgg.2016.50.8687.
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Main issues related to the geomorphological mapping of quarries are discussed. The stages of creating these maps are characterized. The first stage is the analysis of raw materials and prefield mapping. The relief in contours with a relatively small value of horizontal crossing (2 m) is depicted in surveying and topographic maps and plans of mines (scale 1:500–1:5000). According to topographic maps and plans of mining the boundaries of main elements of relief can be quite easy to distinguish, and sometimes their genesis can be set. Space photos help to identify not only the major but also the minor (small) elements and forms of relief and micro-relief surfaces (flat, hilly etc.). As a result of preparatory (prefield) the geomorphological map-hypothesis (preliminary geomorphological map) is worked out, the main morphological elements of relief are highlighted there to the most possible extent. The second most important, phase is field mapping. The main task is to identify the complete and final elements and landforms. Four major components of the quarry relief, which are represented on geomorphic maps (its morphology, genesis, age and dynamics) are analysed. The relief morphology is the most essential part of the content of geomorphologic maps of quarries. The morphological criteria define the boundaries of cells and landforms, and confirm or deny the previously allocated limits, specify them (including changes in the relief that have occurred in recent years) and circumstance them. The genesis of quarries relief, in general, is purely anthropogenic. Depending on the relief forming factor (anthropogenic denudation or accumulation) the main genetic categories of relief are distinguished respectively: excavated (or denudational) and accumulative. The age of the relief is determined by the fund and literary sources, topographic and surveying maps, remote materials. Additional criteria that can be found in field studies can also be used, such as: 1) herbage (amount of turf); 2) forestry (approximate age of trees); 3) the severity of morphological forms. Contemporary geomorphological processes in quarries are the natural and anthropogenic processes that occur in man-made terrain, but act as natural. From the experience of personal research, the most common processes include landfall-landslides processes, linear erosion, sheet erosion, upheaval, suffusion. Some other characteristics that are represented on geomorphological maps include geological structure, vegetation, hydrological features. The main geological characteristic is the lithology of deposits, first and foremost the lithology of career ledges (loam, sand, marl, limestone, sandstone etc.). Vegetation on geomorphic maps of quarries is of secondary importance. Its presence indicates the relative maturity of the human terrain, insignificant activity of modern exogenous processes. Hydrological features of quarries usually consist in the amount of water on separate areas (bottoms of quarries) and waterlogging. The last stage is drawing the legend and mapping of the geomorphological map. Legend to the geomorphological map consists of the following components: 1) the types of human terrain, which are divided into key elements (rarely forms) of relief; 2) small (minor) elements and landforms; 3) the contemporary geomorphological processes (contemporary morphodynamics); 4) other markings. The most essential in the legend is the first part that actually describes the main elements and landforms of quarry relief grouped according to genetics and further divided by age and morphology, topography, geological and hydrological characteristics, vegetation. There are no specific standards as to geomorphological maps mapping. There are black and white and colour versions of the maps. Key words: quarry, anthropogenic relief, geomorphological mapping, geomorphological maps stages of construction, contemporary morhpodynamics
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Gucevic, Jelena, Vukan Ogrizovic, Olivera Vasovic, and Sinisa Delcev. "Staking-out projected boundaries of natural property Vrsac Mountains using the RTK GPS/glonass method." Glasnik Srpskog geografskog drustva 92, no. 4 (2012): 79–98. http://dx.doi.org/10.2298/gsgd1204079g.
Full textAbstract:
The existing topographic and cadastral maps of the former Yugoslav republics are in Gauss-Kr?ger projection on Bessel ellipsoid. For the collected GPS data to comply with the existing cartographic material, it is necessary to provide the transformation parameters from WGS84 to Bessel ellipsoid and according to the principles of cartographic mapping, to make mappings in the plane of the State Coordinate System (SCS). The aim of this research is to present the surveying activities necessary for the establishment and maintenance of digital cartographic basis, which is shown in the test area of ?VRSAC MOUNTAINS?, a Serbian region with outstanding characteristics. In order to establish a connection between the collected data, it is necessary to primarily calculate the parameters of transformation from WGS84 into the SCS. After the vectorisation of projected boundaries from bases made in the SCS, the transformation of vectorised boundary lines from SCS into the WGS84 is carried out, followed by staking the boundaries. To understand the fundamental differences in the methodology of using GPS receivers, it is important to emphasise that the concept of GPS determination of the coordinates is generally divided into absolute and relative positioning. If the correct procedure of GPS positioning, applied to certain environmental conditions, is not followed, the error up to 200 m could be expected. Conclusions are drawn about the selection of staking methods, related to the applied instruments and specific field conditions. The stakeout procedures are given in accordance with the principles of geodetic positioning.
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Mierzwiak, Michal, and Beata Calka. "Multi-Criteria Analysis for Solar Farm Location Suitability." Reports on Geodesy and Geoinformatics 104, no. 1 (December 20, 2017): 20–32. http://dx.doi.org/10.1515/rgg-2017-0012.
Full textAbstract:
Abstract Currently the number of solar farms, as a type of renewable sources of energy, is growing rapidly. Photovoltaic power stations have many advantages, which is an incentive for their building and development. Solar energy is readily available and inexhaustible, and its production is environmentally friendly. In the present study multiple environmental and economic criteria were taken into account to select a potential photovoltaic farm location, with particular emphasis on: protected areas, land cover, solar radiation, slope angle, proximity to roads, built-up areas, and power lines. Advanced data analysis were used because of the multiplicity of criteria and their diverse influence on the choice of a potential location. They included the spatial analysis, the Weighted Linear Combination Technique (WLC), and the Analytic Hierarchy Process (AHP) as a decisionmaking method. The analysis was divided into two stages. In the first one, the areas where the location of solar farms was not possible were excluded. In the second one, the best locations meeting all environmental and economic criteria were selected. The research was conducted for the Legionowo District, using data from national surveying and mapping resources such as: BDOT10k (Database of Topographic Objects), NMT (Numerical Terrain Model), and lands and buildings register. Finally, several areas meeting the criteria were chosen. The research deals with solar farms with up to 40 kW power. The results of the study are presented as thematic maps. The advantage of the method is its versatility. It can be used not only for any area, but with little modification of the criteria, it can also be applied to choose a location for wind farms.
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Klapa, Przemysław, and Bartosz Mitka. "Application of terrestrial laser scanning to the development and updating of the base map." Geodesy and Cartography 66, no. 1 (June 1, 2017): 59–71. http://dx.doi.org/10.1515/geocart-2017-0002.
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Abstract The base map provides basic information about land to individuals, companies, developers, design engineers, organizations, and government agencies. Its contents include spatial location data for control network points, buildings, land lots, infrastructure facilities, and topographic features. As the primary map of the country, it must be developed in accordance with specific laws and regulations and be continuously updated. The base map is a data source used for the development and updating of derivative maps and other large scale cartographic materials such as thematic or topographic maps. Thanks to the advancement of science and technology, the quality of land surveys carried out by means of terrestrial laser scanning (TLS) matches that of traditional surveying methods in many respects. This paper discusses the potential application of output data from laser scanners (point clouds) to the development and updating of cartographic materials, taking Poland’s base map as an example. A few research sites were chosen to present the method and the process of conducting a TLS land survey: a fragment of a residential area, a street, the surroundings of buildings, and an undeveloped area. The entire map that was drawn as a result of the survey was checked by comparing it to a map obtained from PODGiK (pol. Powiatowy Ośrodek Dokumentacji Geodezyjnej i Kartograficznej – Regional Centre for Geodetic and Cartographic Records) and by conducting a field inspection. An accuracy and quality analysis of the conducted fieldwork and deskwork yielded very good results, which provide solid grounds for predicating that cartographic materials based on a TLS point cloud are a reliable source of information about land. The contents of the map that had been created with the use of the obtained point cloud were very accurately located in space (x, y, z). The conducted accuracy analysis and the inspection of the performed works showed that high quality is characteristic of TLS surveys. The accuracy of determining the location of the various map contents has been estimated at 0.02-0.03 m. The map was developed in conformity with the applicable laws and regulations as well as with best practice requirements.
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Crawford, Brandon, Erika Swanson, Emily Schultz-Fellenz, Adam Collins, Julian Dann, Emma Lathrop, and Damien Milazzo. "A New Method for High Resolution Surface Change Detection: Data Collection and Validation of Measurements from UAS at the Nevada National Security Site, Nevada, USA." Drones 5, no. 2 (April 14, 2021): 25. http://dx.doi.org/10.3390/drones5020025.
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The use of uncrewed aerial systems (UAS) increases the opportunities for detecting surface changes in remote areas and in challenging terrain. Detecting surface topographic changes offers an important constraint for understanding earthquake damage, groundwater depletion, effects of mining, and other events. For these purposes, changes on the order of 5–10 cm are readily detected, but sometimes it is necessary to detect smaller changes. An example is the surface changes that result from underground explosions, which can be as small as 3 cm. Previous studies that described change detection methodologies were generally not aimed at detecting sub-5-cm changes. Additionally, studies focused on high-fidelity accuracy were either computationally modeled or did not fully provide the necessary examples to highlight the usability of these workflows. Detecting changes at this threshold may be critical in certain applications, such as global security research and monitoring for high-consequence natural hazards, including landslides. Here we provide a detailed description of the methodology we used to detect 2–3 cm changes in an important applied research setting—surface changes related to underground explosions. This methodology improves the accuracy of change detection data collection and analysis through the optimization of pre-field planning, surveying, flight operations, and post-processing the collected data, all of which are critical to obtaining the highest output data resolution possible. We applied this methodology to a field study location, collecting 1.4 Tb of images over the course of 30 flights, and location data for 239 ground control points (GCPs). We independently verified changes with orthoimagery, and found that structure-from-motion, software-reported root mean square errors (RMSEs) for both control and check points underestimated the actual error. We found that 3 cm changes are detectable with this methodology, thereby improving our knowledge of a rock’s response to underground explosions.
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Paolini, P., G. Forti, G. Catalani, S. Lucchetti, A. Menghini, A. Mirandola, S. Pistacchio, U. Porzia, and M. Roberti. "FROM ”SAPIENZA” TO “SAPIENZA, STATE ARCHIVES IN ROME”. A LOOPING EFFECT BRINGING BACK TO THE ORIGINAL SOURCE COMUNICATION AND CULTURE BY INNOVATIVE AND LOW COST 3D SURVEYING, IMAGING SYSTEMS AND GIS APPLICATIONS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-5/W8 (April 7, 2016): 17–24. http://dx.doi.org/10.5194/isprs-archives-xl-5-w8-17-2016.
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High Quality survey models, realized by multiple Low Cost methods and technologies, as a container to sharing Cultural and Archival Heritage, this is the aim guiding our research, here described in its primary applications. The SAPIENZA building, a XVI century masterpiece that represented the first unified headquarters of University in Rome, plays since year 1936, when the University moved to its newly edified campus, the role of the main venue for the State Archives. By the collaboration of a group of students of the Architecture Faculty, some integrated survey methods were applied on the monument with success. The beginning was the topographic survey, creating a reference on ground and along the monument for the upcoming applications, a GNNS RTK survey followed georeferencing points on the internal courtyard. Dense stereo matching photogrammetry is nowadays an accepted method for generating 3D survey models, accurate and scalable; it often substitutes 3D laser scanning for its low cost, so that it became our choice. Some 360° shots were planned for creating panoramic views of the double portico from the courtyard, plus additional single shots of some lateral spans and of pillars facing the court, as a single operation with a double finality: to create linked panotours with hotspots to web-linked databases, and 3D textured and georeferenced surface models, allowing to study the harmonic proportions of the classical architectural order. The use of free web Gis platforms, to load the work in Google Earth and the realization of low cost 3D prototypes of some representative parts, has been even performed.
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Wu, D., Y. Du, F. Su, W. Huang, and L. Zhang. "AN IMPROVED DEM CONSTRUCTION METHOD FOR MUDFLATS BASED ON BJ-1 SMALL SATELLITE IMAGES: A CASE STUDY ON BOHAI BAY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3 (April 30, 2018): 1871–78. http://dx.doi.org/10.5194/isprs-archives-xlii-3-1871-2018.
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The topographic measurement of muddy tidal flat is restricted by the difficulty of access to the complex, wide-range and dynamic tidal conditions. Then the waterline detection method (WDM) has the potential to investigate the morph-dynamics quantitatively by utilizing large archives of satellite images. The study explores the potential for using WDM with BJ-1 small satellite images to construct a digital elevation model (DEM) of a wide and grading mudflat. Three major conclusions of the study are as follows: (1) A new intelligent correlating model of waterline detection considering different tidal stages and local geographic conditions was explored. With this correlative algorithm waterline detection model, a series of waterlines were extracted from multi-temporal remotely sensing images collected over the period of a year. The model proved to detect waterlines more efficiently and exactly. (2) The spatial structure of elevation superimposing on the points of waterlines was firstly constructed and a more accurate hydrodynamic ocean tide grid model was used. By the newly constructed abnormal hydrology evaluation model, a more reasonable and reliable set of waterline points was acquired to construct a smoother TIN and GRID DEM. (3) DEM maps of Bohai Bay, with a spatial resolution of about 30&thinsp;m and height accuracy of about 0.35&thinsp;m considering LiDAR and 0.19&thinsp;m considering RTK surveying were constructed over an area of about 266&thinsp;km<sup>2</sup>. Results show that remote sensing research in extremely turbid estuaries and tidal areas is possible and is an effective tool for monitoring the tidal flats.
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Smekalova, Tatiana, and Maja Kashuba. "Remote sensing in the study of Late Bronze Age settlements in North-Western Crimea." InterCarto. InterGIS 26, no. 4 (2020): 299–310. http://dx.doi.org/10.35595/2414-9179-2020-4-26-299-310.
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The article is devoted to the results of applying a comprehensive interdisciplinary methodology combining remote sensing methods, GIS, geophysical and archaeological research the Late Bronze for revealing and investigation of the Late Bronze Age settlements in the North-Western Crimea. The discovery of these settlements causes a certain difficulty, since they are buried under a layer of soil and do not have direct visual signs. A comprehensive step-by-step method of non-destructive remote sensing was developed, including the analysis of high-resolution satellite images in the Google Earth Pro resource, identifying promising areas by plant and landscape features, creating GPS routes for ground reconnaissance, geophysical surveys (magnetic and electromagnetic) on promising areas for identifying Late Bronze Age settlements, GPS mapping of surface material, point archaeological sounding. All the results obtained are placed in a special geo-information system, the substrate layers of which are detailed topographic, soil, geological, hydrogeological, digital relief maps. As a result, 48 new settlements of the Late Bronze Age were identified, including 19 settlements with double stone pens. These pens were first discovered only with help of remote sensing methods, especially magnetic surveying. The final answer about the existence and layout of the settlement of the Late Bronze Age before the archaeological excavations is given only by magnetic and electromagnetic surveys. The GIS created on the monuments of the Late Bronze Age in the North-Western Crimea will serve both scientific purposes and to preserve the cultural heritage of the Republic of Crimea, which is especially important in conditions of rapid economic development of land and the construction of trunk roads.
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Brozena, John M., and Mary F. Peters. "An airborne gravity study of eastern North Carolina." GEOPHYSICS 53, no. 2 (February 1988): 245–53. http://dx.doi.org/10.1190/1.1442459.
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The Naval Research Laboratory (NRL) has developed a prototype airborne gravity measurement system. The core of the system is a LaCoste and Romberg air‐sea gravity meter mounted on a three‐axis stable platform. Corrections to the gravimeter data for altitude and variations in altitude are determined from a combination of highly precise radar and pressure altimeters. The original prototype system was designed for use over oceanic areas. We recently incorporated the pressure measurement to extend use of the airborne system to terrestrial regions where occasional radar altitudes over points of known topographic height can be obtained. The radar heights are used to relate the pressure altitudes to absolute altitudes and to determine the slopes of the isobaric surfaces. Vertical accelerations due to horizontal velocity over a curved, rotating earth (the Eötvös correction) and precise two‐dimensional positions are determined from a Texas Instrument P-code global positioning system. The updated system was tested over eastern North Carolina and the Outer Banks, an area that is difficult to survey by conventional means. Over one‐third of the region consists of low lying swampy terrain and another one‐third is the shallow water of the Pamlico and Albemarle Sounds. Neither the land method nor the shipboard gravity surveying method is well suited for these types of areas. Flying at an altitude of 600 m at 375 km/hr, we were able to cover an area over [Formula: see text] with a nominal track spacing of 9 km by 9 km in less than 18 hours of flying time. A comparison by the Defense Mapping Agency showed a 2.8 mGal rms and a −0.2 mGal mean difference between ground truth data and the airborne data at grid points when both data sets were interpolated to a common 9 km grid.
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TATARINTSEV, Vladimir, Leonid TATARINTSEV, Alex MATSYURA, and Andrei BONDAROVICH. "ORGANIZATION OF SUSTAINABLE AGRICULTURAL LAND USE BASED ON LANDSCAPE ANALYSIS." Sustainable Development of Mountain Territories 12, no. 3 (September 30, 2020): 339–48. http://dx.doi.org/10.21177/1998-4502-2020-12-3-339-348.
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The aim of the work was the landscape analysis of agricultural geographical landscapes in the Altai Territory and elaboration of measures aimed at the rational use of agricultural lands. Environmental and landscape (landscape) approach became the main method of scientific research used in the analysis of modern agricultural landscapes. The cartographic method, using GIS-technologies, made it possible to digitize the obtained materials. Synthesized maps of agro-ecological, natural and other zoning of territories are based on topographic, soil, geobotanical and other thematic maps made during land surveying during the field survey. Retrospective analysis, induction and deduction methods,analysis and synthesis, as well as the abstract-logic method were also used in the work. Our main result was the analysis of land use territory for agricultural enterprise in municipal district of Altai Krai. Exploration of lands indicates a pronounced plant-growing specialization of JSC “Pobeda” with a developed animal breeding direction. Limiting factors affecting the rational use of land are natural and climatic conditions, terrain,unsystematic anthropogenic activity and, as a result, the development of erosion processes. The degree of eroded and deflated arable land is more than 50%, hay and pasture lands are also very unstable. Landscapes have been typified, based on which eleven types of land have been identified and their geomorphological description has been carried out. The first five types of land can be used for agricultural production with limitations compensated by crop technology and erosion control measures, the sixth and seventh types require grassing and, in some cases,conservation, the eighth and ninth types can be partially used for pasture and area valorization; the remaining two are not suitable for agricultural use but should be potentially used for planting and forest management. As a result of the presented transformation of agricultural lands, the structure of cultivated areas has changed. The area of arable land decreased by 877 ha, and of pastures by 365 ha,while the area under hayfields, fallow lands, and forest lands increased by 295, 191, and 875 ha respectively. Low-productive lands were withdrawn from agriculture. We suggested that the sustainability of agricultural land use was mainly caused by the reduction of anthropogenic load and increase in ecological equilibrium of the territory.
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Pauknerova, E., P. Sidlichovsky, S. Urbanas, and M. Med. "THE EUROPEAN LOCATION FRAMEWORK – FROM NATIONAL TO EUROPEAN." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (June 13, 2016): 181–86. http://dx.doi.org/10.5194/isprsarchives-xli-b4-181-2016.
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The European Location Framework (ELF) means a technical infrastructure which will deliver authoritative, interoperable geospatial reference data from all over Europe for analysing and understanding information connected to places and features. The ELF has been developed and set up through the ELF Project, which has been realized by a consortium of partners (public, private and academic organisations) since March 2013. Their number increased from thirty to forty in the year 2016, together with a project extension from 36 to 44 months. The project is co-funded by the European Commission’s Competitiveness and Innovation Framework Programme (CIP) and will end in October 2016. In broad terms, the ELF Project will deliver a unique gateway to the authoritative reference geospatial information for Europe (harmonised pan-European maps, geographic and land information) sourced from the National Mapping and Cadastral Authorities (NMCAs) around Europe and including transparent licensing. This will be provided as an online ELF web service that will deliver an up-to-date topographic base map and also as view & download services for access to the ELF datasets. To develop and build up the ELF, NMCAs are accompanied and collaborate with several research & academia institutes, a standardisation body, system integrators, software developers and application providers. The harmonisation is in progress developing and triggering a number of geo-tools like edge-matching, generalisation, transformation and others. ELF will provide also some centralised tools like Geo Locator for searching location based on geographical names, addresses and administrative units, and GeoProduct Finder for discovering the available web-services and licensing them. ELF combines national reference geo-information through the ELF platform. ELF web services will be offered to users and application developers through open source (OSKARI) and proprietary (ArcGIS Online) cloud platforms. Recently, 29 NMCAs plus the EuroGeographics – their pan-European umbrella association, contribute to the ELF through an enrichment of data coverage. As a result, over 20 European countries will be covered with the ELF topo Base Map in 2016. Most countries will contribute also with other harmonized thematic data for viewing or down-loading. To overcome the heterogeneity of data resources and diversity of languages in tens of European countries, ELF builds on the existing INSPIRE rules and its own coordination and interoperability measures. ELF realisation empowers the implementation of INSPIRE in Europe and it complements related activities of European NMCAs, e.g. Czech Office for Surveying, Mapping and Cadastre (CUZK), which provides a large portfolio of spatial data/services and contributes significantly to the NSDI of Czech Republic. CUZK is also responsible for the Base Register of Territorial Identification, Addresses and Real Estates (RUIAN) – an important pillar of Czech e-Government. CUZK became an early-bird in implementing INSPIRE and it provides to the ELF a number of compliant datasets and web services. CUZK and the Polish NMCA (GUGiK) collaborate in the Central-European ELF Pilot (cluster) and test various cross-border prototypes. The presentation combines the national and crossborder view and experiences of CUZK and the European perspective of EuroGeographics.
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Pauknerova, E., P. Sidlichovsky, S. Urbanas, and M. Med. "THE EUROPEAN LOCATION FRAMEWORK – FROM NATIONAL TO EUROPEAN." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B4 (June 13, 2016): 181–86. http://dx.doi.org/10.5194/isprs-archives-xli-b4-181-2016.
Full textAbstract:
The European Location Framework (ELF) means a technical infrastructure which will deliver authoritative, interoperable geospatial reference data from all over Europe for analysing and understanding information connected to places and features. The ELF has been developed and set up through the ELF Project, which has been realized by a consortium of partners (public, private and academic organisations) since March 2013. Their number increased from thirty to forty in the year 2016, together with a project extension from 36 to 44 months. The project is co-funded by the European Commission’s Competitiveness and Innovation Framework Programme (CIP) and will end in October 2016. In broad terms, the ELF Project will deliver a unique gateway to the authoritative reference geospatial information for Europe (harmonised pan-European maps, geographic and land information) sourced from the National Mapping and Cadastral Authorities (NMCAs) around Europe and including transparent licensing. This will be provided as an online ELF web service that will deliver an up-to-date topographic base map and also as view & download services for access to the ELF datasets. To develop and build up the ELF, NMCAs are accompanied and collaborate with several research & academia institutes, a standardisation body, system integrators, software developers and application providers. The harmonisation is in progress developing and triggering a number of geo-tools like edge-matching, generalisation, transformation and others. ELF will provide also some centralised tools like Geo Locator for searching location based on geographical names, addresses and administrative units, and GeoProduct Finder for discovering the available web-services and licensing them. ELF combines national reference geo-information through the ELF platform. ELF web services will be offered to users and application developers through open source (OSKARI) and proprietary (ArcGIS Online) cloud platforms. Recently, 29 NMCAs plus the EuroGeographics – their pan-European umbrella association, contribute to the ELF through an enrichment of data coverage. As a result, over 20 European countries will be covered with the ELF topo Base Map in 2016. Most countries will contribute also with other harmonized thematic data for viewing or down-loading. To overcome the heterogeneity of data resources and diversity of languages in tens of European countries, ELF builds on the existing INSPIRE rules and its own coordination and interoperability measures. ELF realisation empowers the implementation of INSPIRE in Europe and it complements related activities of European NMCAs, e.g. Czech Office for Surveying, Mapping and Cadastre (CUZK), which provides a large portfolio of spatial data/services and contributes significantly to the NSDI of Czech Republic. CUZK is also responsible for the Base Register of Territorial Identification, Addresses and Real Estates (RUIAN) – an important pillar of Czech e-Government. CUZK became an early-bird in implementing INSPIRE and it provides to the ELF a number of compliant datasets and web services. CUZK and the Polish NMCA (GUGiK) collaborate in the Central-European ELF Pilot (cluster) and test various cross-border prototypes. The presentation combines the national and crossborder view and experiences of CUZK and the European perspective of EuroGeographics.
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Iescheck, Andrea Lopes, and Patricia Andréia Paiola Scalco. "Validating the vertical quality of SRTM digital elevation model of the Mirim Lagoon hydrographic basin." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-136-2019.
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<p><strong>Abstract.</strong> This work is part of a research project that aims at the automatic determination of knickpoints and the assessment of morphometric and hypsometric parameters of Mirim Lagoon Hydrographic Basin, using Shuttle Radar Topography Mission digital elevation model (SRTM-DEM) and spatial analyses.</p><p>The analysis of geomorphologic systems is done using computational treatment of data obtained by remote sensing, especially those obtained by SRTM. These data permit the elaboration of a topographic model for the Earth surface and provide a base for studies in several units of geomorphologic analyses (geomorphologic systems), such as hydrographic basins.</p><p>The most usual technique for derivation of relief morphologic attributes is based on digital elevation models (DEMs) and digital hydrographic nets. Computational routines are applied on those data for acquisition of the hydrography and drainage anomalies. The DEMs and the hydrographic nets must have either morphologic or hydrologic consistency to validate the results obtained in the morphometric analyses.</p><p>More specifically, this study aims at describing the method and related results regarding the validation of the vertical accuracy of SRTM-DEM through a kinematic positioning based on the Global Navigation Satellite System (GNSS), in the Mirim Lagoon Hydrographic Basin region. Mirim Lagoon Hydrographic Basin is as cross-border basin located on the Atlantic coast of South America, and covers an area of 58,407.78&thinsp;km<sup>2</sup>, where 47% of this area is in Brazil and 53% in Uruguay.</p><p>Several studies deal with the validation of Digital Elevation Models (DEMs) and SRTM data using different GNSS surveying methods and receivers. The innovation of this work is the methodology developed to achieve the suitable accuracy for the control points coordinates to validate the SRTM-DEM of Mirim Lagoon Hydrographic Basin. The study used the kinematic relative positioning method with a recording rate of 1 second and without reference stations for post-processing with the precise point positioning (PPP) method. This methodology allowed covering a large area with reference stations being very far from the surveyed region and with different geodetic reference systems (two countries).</p><p>The methodology entails the GNSS data acquisition and post-processing, the transformation from geometric heights into orthometric heights, the SRTM-DEM mosaic, the extraction of homologous points in the SRTM-DEM and the statistical analyses for validating the model.</p><p>The study used a GNSS receiver of dual-frequency with recording rate of 1 second to collect a total of 275,916 points with 3D coordinates. Those points were post-processed using the PPP method with the Canadian Spatial Reference System &ndash; Precise Point Positioning (CSRS-PPP), and the ellipsoidal height was converted into orthometric height through the software INTPT geoid. During this work, we used the geopotential model (EGM96) to transform height differences between two countries, Brazil and Uruguay.</p><p>In order to obtain the SRTM-DEM we used 15 SRTM images, version 3, band C, with a spatial resolution of 1 arcsecond (approximately 30&thinsp;m). These images were individually processed to obtain the Digital Elevation Model Hydrologically Consistent (DEMHC) and to treat the inconsistencies. Afterwards, we created a mosaic with the 15 images.</p><p>In the statistical analysis we examined the magnitude of absolute errors in the SRTM data. These errors were named discrepancies between the SRTM heights and the heights of GNSS survey points. After the post-processing and the heights conversion, the GNSS survey points were considered accurate and used as a reference for SRTM-DEM validation. The goal of the statistical analysis was to verify if the absolute vertical precision of the DEM data exceeds 16&thinsp;m, according to the precision specifications of the DEM SRTM.</p><p>Results showed that the vertical mean absolute error of the SRTM-DEM vary from 0.07&thinsp;m to &plusmn;&thinsp;9.9&thinsp;m with average of &minus;0.28&thinsp;m. This vertical accuracy is better than the absolute vertical accuracy value of &plusmn;&thinsp;16&thinsp;m published in the SRTM data specification and validates the SRTM-DEM. Besides that, even considering different slopes and different heights the statistics showed that SRTM-DEM could be validated, in spite of the results for lower and flat area were more accurate than the ones for a higher area with high slope.</p>
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Purwanto, Ajun. "Study on Geomorphology of Cepogo Sub-District, Boyolali, Central Java." Forum Geografi 11, no. 1 (January 1, 2004). http://dx.doi.org/10.23917/forgeo.v11i1.497.
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There are two point of this geomorphological research. Firstly, to study the characteristic or physical condition of the observed area. Secondly, data providing or geomorphology information extracted from geomorphological map of scale 1 : 25.000. this research included literature study collecting of primary and secondary data. The method applied in this researh was the map interpretation of the observed area. The maps interpretation included topographical, geological, slope, and soil. Fieldwork was carried out to compare the result of maps interpretation with the facts of field, all at once for recording and surveying of the field physical data observed in the research. There were four types of recorded physical data i.e morphology, morphogenesis, morphocronology,, and morphoarrangement. In the research there was known that the observed area consists of an origin landform i.e. formation of volcanic origin and distinguished into nine units of landform. In broad outline, in the observed area of the research, there were many geomorphological processes i.e. weathering, erosion, and massdenudation of rocks, and there were also found steeply slopes deep valleys and formation of alluvial fan.
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Smaczyński, Maciej, and Tymoteusz Horbiński. "Creating 3D Model of the Existing Historical Topographic Object Based on Low-Level Aerial Imagery." KN - Journal of Cartography and Geographic Information, November 10, 2020. http://dx.doi.org/10.1007/s42489-020-00061-0.
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Abstract The aim of the research was to create 3D cartographic visualization based on various sources and data types of an existing historical topographic object. The authors will present the stages of the research for the historical windmill located in Poland. The most recent surveying methods, such as GNSS method, low-level aerial photogrammetry and advanced IT tools, including computer software, will be applied for this purpose. The sequence of research procedures adopted by the authors of this article allowed for the creation of a 3D model of the tested windmill and its implementation into the Internet environment. This allowed to increase the cartographic range of spatial information. In addition, the research results allow for the extension of research in the field of history and can be the basis for their implementation.