Virtual Globe Research Articles

Geo-spatial hypertext in virtual reality: mapping and navigating global news event spaces

ABSTRACT Every day, a myriad of events take place that are documented and shared online through news articles from a variety of sources. As a result, as users navigate the Web, the volume of data can lead to information overload, making it difficult to find specific details about an event. We present News in Time and Space (NiTS) to address this issue: NiTS is a fully immersive system integrated into Va.Si.Li-Lab that organises textual information in a geospatial hypertext system in virtual reality. With NiTS, users can visualise, filter and interact with information currently based on GDELT on a virtual globe providing document networks to analyse global events and trends. The article describes NiTS, its event semantics and architecture. It evaluates NiTS in comparison to a classic search engine website, extended by NiTS's information filtering capabilities to make it comparable. Our comparison with this website technology, which is directly linked to the user's usage habits, shows that NiTS enables comparable information exploration even if the users have little or no experience with VR. That is, we observe an equivalent search result behaviour, but with the advantage that VR allows users to get their results with a higher level of usability without distracting them from their tasks. Through its integration with Va.Si.Li-Lab, a simulation-based learning environment, NiTS can be used in simulations of learning processes aimed at studying critical online reasoning, where Va.Si.Li-Lab guarantees that this can be done in relation to individual or groups of learners.

Enhancing Spatial Thinking Awareness of World-Scale Geography with Excel Dynamic Map Charts and Virtual Globes

Spatial thinking is a unique thinking skill that geographers use to reason. Every individual is believed to have this thinking skill, but not all are aware of it. This condition causes differences in the development of each person. A person’s spatial thinking can be improved by training. Geospatial technology is a representation tool that many people believe can be used to train spatial thinking skills. However, not many people encounter obstacles when using this technology. The complexity of the command to run is an obstacle that is often found. In line with the development of geospatial technology, many applications integrate this technology as part of visualization tools. This teaching and learning were conducted with Action Research Classroom (three cycles) in the form of Project-Based Learning with Science, Engineering, Technology, and Mathematic (STEM) approach. This article discusses the findings of the research on the use of Excel dynamic map chart and virtual globe to improve spatial thinking in research subjects with the case study of Indonesian Geography and World Regional Geography. With the Excel application project, for the context of upper-level education, the findings show an increase in spatial thinking skills and mastery of the use of mapping platforms without the need for prior experience of coding, software, or cartography, although it needs to be corroborated by other studies.

Google Earth Augments Viewing the Spectacle of Ruin in Selected ‘In-Between Places’ of Old Industrial Johannesburg

South Africa is said to have the worst social inequality in the world, and examples of this inequality can be seen in the shack settlements, backyard shacks and hijacked properties in many parts of the city of Johannesburg. These unsafe and neglected ‘interstitial places’ are where the poor live in inadequate housing, squeezed between factory buildings, railway lines and motorways in the city. One of the challenges of capturing visual information about these settlements in these difficult settings is getting access to the areas where photographs can be taken. In Johannesburg, many areas are no longer safe for outsiders to visit. These unsafe, informal and often well-hidden areas can be considered ‘interstitial’ in relation to other areas where middle-income earners live in decent houses in pleasant suburbs with amenities. It is these ‘unsafe’ areas that the author wished to explore as a source of images and impressions for creative works.
 This study takes an autoethnographic approach to exploring three neglected suburbs of Johannesburg, South Africa (Cleveland, Denver and Jeppestown), which all date from soon after the first discovery of gold in 1886. Through this work, the author hoped to make sense of observed changes within the city and the proliferation of informal, survivalist settlements seemingly arising without town planning interventions. Many open areas and dilapidated buildings are now occupied by low-income earners, perhaps because city governance has been overwhelmed by the thousands of work-seeking migrants arriving in the city on an ongoing basis.
 To explore the many visual indicators of poverty in these selected areas of Johannesburg, the author used Google Earth remote sensing images and Google Earth Street View to augment site visits. Google Earth is a valuable research tool, as one can quickly explore marginal areas that are not safe for outsiders to visit. One can also view activities that are not visible from the street – for example, illegal motor repair operations occurring behind high walls. Ethical issuesabound in these acts of anonymous looking at the poor and destitute and finding the picturesque in neglected buildings, dismal living conditions and slums, as well as the privacy and surveillance issues relating to those being observed. This essay will dwell on some of the benefits of the Google Earth virtual globe software, as well as the ethical discomfort that can result when observing people, poverty and informal living places – whether using remote sensing methods and driving around these areas with a camera, or using the images and perceptions gained for personal use as a source of inspiration for art making and fiction writing.

A novel continual reinforcement learning-based expert system for self-optimization of soft real-time systems

Virtual globes are soft real-time systems, which stream multi-resolution data sets and render world-scale landscapes in real-time. Such systems require an adaptation mechanism to fulfill user and quality of experience (QoE) requirements. Configuration and tuning of parameters to optimize system performance is challenging due to run-time uncertainties. In this work, we propose a continual reinforcement learning-based expert system for self-optimization of a soft real-time system to meet user and quality objectives. The proposed system is capable of learning continuously by utilizing the previously learned knowledge to fulfill adaptation requirements. The proposed managing system interacts with a managed system and evolves a knowledge base of adaptation rules for run-time optimization of the managed system to meet user and quality objectives. We devise a learning classifier system for the evolution, storage, and transfer of adaptation rules using a code fragments-based rich encoding scheme. We transform user goals, system states, and execution environment conditions into observable states. We validated the proposed system for the same and cross-domain knowledge transfer and reuse scenarios for different user goals and execution environments. The results of the proposed system are compared with baseline and state-of-the-art methods where the proposed system outperformed the methods in terms of adaptation accuracy.

Digitization, Visualization and Accessibility of Globe Virtual Collection: Case Study Jüttner’s Globe

The aim of the article is to prepare a model for making available metadata and digital objects of the new Globe Virtual Collection for the Map Collection of the Faculty of Science of Charles University. The globes are special cartographic documents; therefore, they are also described in a special way. The article deals with the digitization, visualization and accessibility of an old globe by Josef Jüttner from 1839, which comes from the depository of one of the most important central European collections. A simple model for a new virtual processing of the globe collection at Charles University is presented. SfM-MVS photogrammetry was chosen for digitization of the globe. The basic elements of the copperplate were set as basic parameters for image acquisition. Contrast, density, black line, line, dash and dot patterns and their complex use were observed for a good graphic design of the globe. Other parameters included a closer determination of the users for whom the resulting product is intended, as well as the profile of the users’ behavior on the site so far. New metadata were extracted from the bibliographic description. The virtual 3D globe was integrated into the database using the Cesium JavaScript library. Metadata and a 3D model of the globe were linked together and made available to the general public on the Globe page of the Map Collection of the Faculty of Science of Charles University. A comparison of web browsers was performed focusing on the loading time of the 3D model on the website. New graphic elements were identified with the new processing. It was possible to read the factual information written on the globe. Different possibilities and limitations of metadata description, photogrammetric methods and web presentation are described. This good practice can be applied by other virtual map collections.

GOOGLE EARTH PLATFORM AS A GEOGRAPHIC INFORMATION SYSTEM AND ITS CAPABILITIES IN THE STUDY OF DISCIPLINES OF SPECIALTY 193 "GEODESY AND LAND MANAGEMENT"

With the rapid development of information technology, there is a need to revise modern education and new approaches to learning. Nowadays, anyone can take advantage of access to Earth observation satellite data. The development of satellite technologies is one of the main and pressing issues of the world. Scientists are increasingly analyzing satellite images in their work. So every year the demand in this direction increased, as did the very accuracy of satellite imagery. One of the platforms with free access to constantly updated satellite imagery is Google Earth and its more advanced versions of Google Earth Pro and Google Earth Engine, which we will consider for solving a certain number of problems. Google Earth is an unusual platform that most people perceive as a virtual globe, but if we consider it as a whole, including extended versions, then from a virtual globe we get a full-fledged geographic information system. The solution of some geodetic problems can be attributed to geoinformation analysis. In scientific sources, the topic of using Google Earth for geodetic purposes is very relevant. With the help of GIS, many issues are solved in the following industries related to 193 specialties, namely: land management; land cadastres; land inventory; mapping, including thematic; remote sensing; design and many other narrower issues. The purpose of this article is to form a list of geodetic and design tasks that can be solved using the Google Earth platform and its improved versions Google Earth Pro, Google Earth Engine when studying the disciplines of specialty 193 "Geodesy and land management". The article discusses modern approaches to learning, which will soon become a new reality for us. The most useful feature for research turned out to be time travel. With this feature, we can explore land changes since 1985, which is a hot topic in the discipline of land management. The Google Earth platform is not a new project, it has evolved since 2005, constantly optimizing its capabilities with the addition of more interesting and useful features. A lot of their own maps have already been created through this platform, and large companies use Google Earth as a demonstration of their projects. Keywords: Google Earth, geoinformation system, satellite images, platform capabilities, modern education.

Tick maps on the virtual globe: First results using the example of Dermacentor reticulatus

Digital maps, particularly displayed on virtual globes, will represent the most important source of geographical knowledge in the future. The best known of these virtual globes is Google Earth, whose use in teaching at schools and universities is now common practice. As the first result of a series of forthcoming digital tick maps, the worldwide distribution of the marsh tick Dermacentor reticulatus is shown on Google Earth. For this purpose, various distribution maps of D. reticulatus were compiled, including digitized expert maps and a map of suitable habitats compiled with a species distribution model (SDM). A random forest model that estimates suitable habitats by combining information from tick observations, bioclimatic variables, altitude, and land cover was chosen for the latter. In the Google Earth application, the following maps can be selected: a historical expert map, a current expert map, a SDM predicted habitat suitability map, a combined expert-habitat suitability map (considered to be the best representation of the current distribution of D. reticulatus), and a map of rasterized tick locations. Users can overlay these maps according to their own requirements or combine it with other Google Earth content. For example, a comparison of the historical with the current expert map shows the spread of D. reticulatus over the past few decades. Additionally, high-resolution city maps of Bilbao (Spain), Grenoble (France), Berlin (Germany), Wrocław (Poland), Budapest (Hungary), Bucharest (Romania), and Tomsk (Russia) demonstrate the urban distribution of D. reticulatus in public parks, fallow land, and recreational areas. The Google Earth application, developed using the Keyhole Markup Language (KML), also contains fact sheets on biology, ecology, seasonal activity, and vector competence of D. reticulatus. This information has been prepared in a compact and easily understandable way for the target group, i.e. scientists from various disciplines, students, and lay people interested in the geographical distribution of ticks.

DYNAMIC AND WEB-BASED 4D VISUALIZATION OF STREETSPACE ACTIVITIES DERIVED FROM TRAFFIC SIMULATIONS AND SEMANTIC 3D CITY MODELS

Abstract. Semantic 3D city models can serve as anchor points for different components of urban digital twins. In addition to static 3D models such as buildings, transportation infrastructure, vegetation, or city furniture, this can also include dynamic processes such as traffic movement or changing traffic signals. Integrating these aspects into a dynamic, realistic, and accessible 4D visualization presents a number of requirements and challenges, which are discussed. While the City Geography Markup Language (CityGML) is a well established OGC standard for modeling and exchanging semantic 3D city models, the Cesium Language (CZML) provides capabilities for visualizing time-dependant properties that can be displayed in the Cesium virtual globe. Results of the open-source microscopic traffic simulation tool SUMO include information on locations and orientations of vehicles, bicycles, pedestrians and other traffic members as well as traffic signal information and can be exported as a CSV table. In order to allow a 4D visualization of these simulation results, a scheme for deriving 3D + t CZML documents from data given as 2D + t CSV files is presented. Additionally, dynamically changing traffic lights are integrated. Based on data available for the city of Munich, a CityGMLcompliant streetspace model is generated. This enables the combination of traffic simulation results and semantic 3D city models within a common Cesium based web-visualization and allows a direct and platform independent access to realistic visualizations of streetspace activities. Since this often results in a huge amount of data, a spatio-temporal tiling strategy enabling the visualization of large CZML data is presented.

A novel method for adaptive terrain rendering using memory-efficient tessellation codes for virtual globes

Virtual globes render large-scale real-world earth’s surface in real-time for geographic information visualization. Modern GPUs have introduced hardware tessellation features for high-performance rendering. Patch-based terrain rendering using hardware tessellation introduces cracks and swimming artifacts during navigation. Hardware tessellation-based terrain rendering methods limit the tessellation factors to power-of-two and render patches with discrete-level-of-detail (DLOD). We present a novel method for adaptive terrain rendering using tessellation codes. In the proposed method, we present novel memory-efficient bit-field-based tessellation codes to encode patch Level-of-detail (LOD). The encoding scheme enabled patch rendering with Continuous-level-of-detail (CLOD) on tessellation hardware. The view-dependent simplification algorithm simplifies and encodes the patch’s Level-of-detail (LOD) in tessellation codes. The proposed method, based on tessellation codes, tessellates patches as uniformly spaced vertices grid. A novel relocation algorithm, based on tessellation codes, relocates uniformly spaced vertices to construct an encoded simplified vertices grid to avoid boundary cracks and swimming artifacts. The tessellation codes consumed 28 kilobytes of memory for a patch size of 65. The proposed method rendered 2.5 million triangles with a frame rate of 570 frames-per second for an ultra-HD display. The proposed method achieved a high simplification and rendering rate with low computational and memory usage as compared to state-of-the-art methods.

Teaching, Learning, and Exploring the Geography of North America with Virtual Globes and Geovisual Narratives

Amid the shift to virtual learning during the COVID-19 pandemic, educators across disciplines were faced with developing new strategies for active learning. This article discusses findings from a case study of using Google Earth for virtual field trips and projects in an undergraduate Geography of North America course, assessing the process of incorporating Google Earth and student perspectives on their engagement with this technology. With broader applications to secondary and post-secondary education contexts, findings suggest increased student engagement and an appreciation for the opportunity to work with a geospatial technology mapping platform without needing prior coding, software, or mapping experience.

OPPORTUNITIES TO USE MOBILE GIS APPLICATIONS IN THE FORMATION OF TOURIST AND LOCAL LORE COMPETENCIES IN STUDENTS: CASE STUDY IN ALMATY, KAZAKHSTAN

Since the use of mobile GIS-applications in the formation of tourist and local lore competencies of students affects the knowledge and professional competence of future teachers, it is very important to first determine the attitude of teachers and professors to the use of mobile GIS-applications and assess the level of use of mobile applications by students. Therefore, this article provides for the possibility of using mobile GIS applications in the organization of tourist and local lore activities of students of the educational program "Geography". The effectiveness of organizing tourist and local lore events using mobile GIS applications was determined by conducting interviews and questionnaires. The survey consisted of two parts, and a total of 72 students took part in it voluntarily. In the course of the study, we studied the formation of tourist and local lore competencies from mobile GIS applications as a result of the study: 1) "Road navigation" from mobile GIS applications - 2GIS (79.1%); 2) "For viewing and studying" from mobile applications - ArcGIS QuickCapture (56.9%); 3) Google planet Earth "Virtual globe" (52.8%); 4) based on the mobile applications "Cartography and Navigation", we determined the efficiency of using the GIS4MOBILE-x (41.7%) and 5) the City bus for "GPS monitoring" (100%). In this regard, we are confident that the use of these mobile applications will be effective in organizing tourist and local lore events. The use of these technologies in teaching makes it possible to update educational approaches, introduce new pedagogical technologies and form competencies.

Interactive computer model for aurora forecast and analysis

An interactive computer model of a short-term (with a horizon 30–70 min) forecast of aurora intensity has been developed in the form of a web-based geoinformation system. The OVATION-Prime empirical model is used as the basic software, which establishes statistical relationships between parameters of the solar wind, the interplanetary magnetic field, and auroral particle fluxes. On the basis of this model, a system has been built which simulates the spatial planetary distribution of the probability of observing auroras and a number of accompanying quantities. Data visualization is carried out on the basis of the virtual globe technology and is provided to the end user via a specialized web service. The forecast has been verified by comparing the model predictions with the data from 16 cameras conducting continuous observations of the auroras in the visible spectrum. The proportion of coincidences between the predicted and observed auroras was 86 %. The developed service enables both forecasting and analysis of past events. The system allows us to compare the spatial distribution of probability of auroras with railway transport systems for the territory of the Russian Federation.

Интерактивная компьютерная модель для прогноза и анализа полярных сияний

An interactive computer model of a short-term (with a horizon 30–70 min) forecast of aurora intensity has been developed in the form of a web-based geoinformation system. The OVATION-Prime empirical model is used as the basic software, which establishes statistical relationships between parameters of the solar wind, the interplanetary magnetic field, and auroral particle fluxes. On the basis of this model, a system has been built which simulates the spatial planetary distribution of the probability of observing auroras and a number of accompanying quantities. Data visualization is carried out on the basis of the virtual globe technology and is provided to the end user via a specialized web service. The forecast has been verified by comparing the model predictions with the data from 16 cameras conducting continuous observations of the auroras in the visible spectrum. The proportion of coincidences between the predicted and observed auroras was 86 %. The developed service enables both forecasting and analysis of past events. The system allows us to compare the spatial distribution of probability of auroras with railway transport systems for the territory of the Russian Federation.

EXPERIENCE OF OBTAINING INITIAL DATA FROM GOOGLE EARTH TO BUILD A DIGITAL TERRAIN MODEL

The Google Earth information system is the virtual globe built on connected photographs with terrain information and partially vectorized situation. The system has the ability to obtain information on the WGS-84 coordinates and the universal transverse Mercator projection of any point, but it requires research on the methodology for obtaining such information and the accuracy of spatial information. The answers to these questions will make it possible to specify the range of geodetic and design tasks that can be solved with Google Earth. It has been analyzed the latest research and publications in article. According to this analysis, the problem of using the Google Earth system for geodetic purposes remains relevant. The work focused on the formation of initial data from the Google Earth system in a convenient text format for further loading into a computer-aided design system to create a digital terrain model. An algorithm for obtaining initial data in the form of four columns has been compiled: the name of the point and three coordinates. In this format, you can perform any coordinate transformations with subsequent loading into other programs. The algorithm for obtaining initial data from Google Earth in text format will be as follows: 1) drawing up a plot survey scheme (determining the survey boundary, alphanumeric designation of streets for simplicity, highlighting survey objects, etc.); 2) creation of closed polygons (general survey area, all areal objects), polylines (all linear objects), marks (all point objects); 3) obtaining geodetic coordinates of nodes of areal objects and polylines; 4) creation of longitudinal profiles for finding heights. The problem of assessing the errors of the Google Earth system in the horizontal plane remains relevant in order to be able to form a digital model of the situation.

Georeferencing 3D Tiles Generated from Photogrammetry-Derived Mesh Using Ground Control Points

In order to achieve efficient visualization of massive 3D photogrammetry models on the web-based virtual globe, original photogrammetry 3D models should be converted into 3D Tiles with accurate georeferencing information to render on the correct surface position. There are a few software tools and online platforms for generating 3D Tiles and various ways to generate 3D Tiles were reported, but none of them do not provide a way to georeference 3D Tiles with GCPs. This paper is intended to suggest an approach to georeference 3D Tiles with GCPs based on the Kabsch algorithm which is very similar to georeferencing raster data with GCPs in the traditional GIS. First, we mathematically describe how to apply the Kabsch algorithm for georeferencing 3D Tiles with GCPs. Following this description, we demonstrate our implementation allowing constructing GCPs and calculating the “transform” property of 3D Tiles. Finally, we tested the suggested method in Construkted Reality which is the platform to stream and visualize massive photogrammetry and point clouds datasets.

A never-born Russian-language earth globe in the Virtual Globes Museum

Abstract. It has been just for more than thirty years that the English-language version of the detachable structural-morphological globe of the Earth with 40 cm diameter produced by the Cartographia Enterprise won the prize of the best demonstration aid (Anson and Gutsell 1989) at the Budapest conference of the International Cartographic Association in August 1989. This success was the result of the cooperation between two education institutions (Kossuth Lajos University and Eötvös Loránd University /ELTE/) and two Hungarian firms (Cartographia Enterprise and School Equipment Producing and Marketing Company). This unique product has been the only thematic earth globe designed and published in Hungary and which was duplicated in a relatively large number. It is a rarity today. This is one of the reasons why this globe has been placed in the Virtual Globes Museum (VGM) (http://terkeptar.elte.hu/vgm). This paper gives an overview of the history of these thematic globes: the Hungarian versions made in 1986 (VGM ID 8, 9, 10) and the English versions published in 1988 (VGM ID 66, 67, 68). It introduces the immediate scientific antecedents of their birth and – being a demonstration aid – the process of publishing. The paper also presents the work with the Russian version of the globe carried out at the Institute of Cartography and Geoinformatics, ELTE (VGM ID 154, 155, 156). This will lead to the expansion of the number of globes in the VGM. The close relationship between the new product and the former two editions is also pointed out.

Visualizing Large-Scale Building Information Modeling Models within Indoor and Outdoor Environments Using a Semantics-Based Method

Building information modeling (BIM), with detailed geometry and semantics of the indoor environment, has become an essential part of smart city development and city information modeling (CIM). However, visualizing large-scale BIM models within geographic information systems (GIS), such as virtual globes, remains a technological challenge with limited hardware resources. Previous methods generally removed indoor features in a single-source (BIM) scene to reduce the computational burden from outdoor views, which have not been applied to the multi-source and -scale geographic environment (e.g., virtual globes). This approach neglected special BIM semantics (e.g., transparent windows), which may miss a part of geographic features or buildings and cause unreasonable visualization. Besides, the method overlooked indoor visualization optimization, which may burden computing resources when visualizing big and complex buildings from indoor views. To address these problems, we propose a semantics-based method for visualizing large-scale BIM models within indoor and outdoor environments. First, we organize large-scale BIM models based on a latitude-longitude grid (LLG) in the outdoor environment; a multilayer cell-and-portal graph is used to index the structure of the BIM model and building entities. Second, we propose a scheduling algorithm to achieve the integrated visualization in indoor and outdoor environments considering BIM semantics. The application of the proposed method to a multi-scale and -source environment confirmed that it can achieve an effective and efficient visualization for huge BIM models in indoor-outdoor scenes. Compared with the previous study, the proposed method considers the BIM semantics and thus can visualize more complete features from outdoor and indoor views of BIM models in the virtual globe. Besides, the study only loads as visible data as possible, which can retain lower the volume of increased geometry, and thus keep a higher frame rate for the tested areas.

GEOVISUALIZATION OF AERIAL PHOTOGRAMMETRIC FLIGHTS FOR DATA QUALITY ASSESSMENT

Abstract. Spatiotemporal data visualization plays an important role for simulating the changes over time and representing dynamic geospatial phenomena. In aerial photogrammetry, image acquisition is the most important stage for obtaining high-quality products; and can be affected by various factors such as the weather and illumination conditions, imaging geometry, etc. 3D simulation of the aircraft trajectories at the planning stage helps the flight planners to make better decisions especially for unmanned aerial vehicle (UAV) missions in areas with mixed land use land cover, such as rugged topography, water bodies, restricted areas, etc.; since images with poor texture or large differences in scale may deteriorate the quality of the final products. In this study, a geovisualization approach for photogrammetric flights carried out with UAVs or airplane platforms was implemented using CesiumJS Virtual Globe. The measured flight trajectory parameters, such as image perspective centre coordinates and the camera rotations, the time of acquisition, and the interior orientation parameters (IOPs) of the camera were used for spatiotemporal visualization. In the developed approach, the EOPs and IOPs of the images were utilized to reconstruct the flight paths, the camera position, the footprints of the acquired images on the ground, and the rotation of the aircraft; and to present them on a 3D web environment precisely. The approach was demonstrated by using two case studies, one from a UAV flight mission and the other one from an airplane carried out with a large-format aerial camera.

ANALYSIS OF GOOGLE EARTH ALTITUDE ERRORS FOR USE IN GEODESIC WORKS

The Google Earth service is an information system with extensive functionality used in the Internet, for mobile devices and for desktop computers. The system is a "virtual globe" built on pooled photographs with the addition of spatial information provided by Alphabet Inc in the coordinate system - WGS 84 and the universal cross-section of Mercator. In the system there is an opportunity to lay a line of a route, to receive a longitudinal profile of this line with marks and a slope. However, the question of the accuracy of spatial information remains. The answer to this question will highlight a range of engineering, geodetic and design tasks that can be solved with this service. The article considers this problem from the analysis of height errors. The accuracy of Google Earth's spatial information can be assessed by comparing it to a geodetic reference object. As such object in this work the data of adjustment of the design documentation for construction of the highway bypassing Novy Bug (the second turn) in the Nikolaev area are taken. In the first stage, a "reference" object has been considered, for which there are spatial data obtained by geodetic methods of a given accuracy. In the second stage, the Google Earth system built a road route and a longitudinal profile. At the third stage the received information was systematized and analyzed. In this work, the accuracy of construction of the longitudinal profile by geodetic methods was reduced due to the construction of a black line of the longitudinal profile through a digital terrain model, and hence due to the standard errors of Delaunay triangulation. When using geometric leveling data, the compatibility of the two longitudinal profiles will increase. With careful preparation of the original data, you can achieve meter accuracy in height. Representation of the Earth's surface with such accuracy can be used in solving many engineering problems: variant design of linear structures, preliminary feasibility study of design solutions and more. In the future, we must to assess the horizontal errors.

DRONE-BASED CONTAINER CRANE INSPECTION: CONCEPT, CHALLENGES AND PRELIMINARY RESULTS

Abstract. Container crane inspection is a very important task to maintain their uninterrupted operation. Nevertheless, this is a costly and time-consuming activity if performed manually. Recently, image-based detection of surface damages or changes using drones has gained increasing interest in industry; especially when objects of interest have a complex structure like container cranes. One main aim of this paper is a single-epoch image analysis which will also serve later for multi-epoch processing. It provides reliable information about current defects that may lead to big damages if not inspected by experts. Naïve Bayes classifier is employed to classify the images in different classes of which critical defects and especially rust is important. The preliminary results show that the precision on the target class reached about 99%. However, 87% percent recall in this class is not enough and it should be improved for this application.Having a large dataset requires an efficient data management system to provide users and decision makers with the information needed. In addition, in order to foster full automation, the aforementioned image analysis component should have a direct connection to the database and thus is able to query image and semantic information. We therefore introduce the second aim of our research, that is a concept for database design. Here, not only the raw data and the final results are integrated but also the intermediate results. At the same time, the database concept is connected to an integrated client interface that allows retrieving data of interest in a virtual globe.