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Open access

Marta Gabryś, Katarzyna Kryszyn and Łukasz Ortyl

Abstract

Intensified investment processes in construction have resulted in increased interest in the methods of efficient detection, verification and location of underground utility networks. In addition to the well-known pipe and cable locating equipment, which has increased its efficiency and reliability through the development of technologies, GPRs are becoming more and more popular.

This publication presents the results of the experimental research carried out with the use of GPRs manufactured by two different companies as well as the results of the verification of underground utilities in real conditions. The GPRs have worked in the mode of the real-time location of their own position using the GNSS system or robotic total stations.

The GPR (Ground Penetrating Radar) surveys performed on a test field, consisting of 9 pipes with a known position, were aimed at assessing the accuracy of their identification on echograms. The utility line location errors were determined using three different combinations between the GPR and the locating instrument. It allowed the evaluation of the possibility of using these solutions for detection, verification and location of underground utility networks in the light of the Polish legal regulations and the British specification PAS 128.

The verification in real conditions was carried out in a typical urban space, characterised by an intense occurrence of underground utilities, that is, sewage systems, gas pipelines and power cables. It was based on the GESUT database captured from the county geodetic and cartographic documentation centre. The results of the visual analysis of the materials captured with the help of two measurement systems were described in detail, however, the verification was carried out only for one set of data. The authors have presented the procedure of processing echograms and detecting the location of pipeline axes based on their vectorisation. The authors of this research paper have performed a numerical analysis of the compliance of the profiles of utility lines with the information from the base map for two variants of the GPR data integration with the coordinates. The authors of this research paper have also presented an alternative concept of capturing the profile of a utility line in the field based on the processing of GPR data in 3D – the so-called C-scan. The conclusions summarise the possible factors affecting the surveying results and the methods of eliminating sources of errors, both for the GPR and geodetic data.

Open access

Gunnar Sivertsen

Abstract

Internationalization is important for research quality and for specialization on new themes in the social sciences and humanities (SSH). Interaction with society, however, is just as important in these areas of research for realizing the ultimate aims of knowledge creation. This article demonstrates how the heterogenous publishing patterns of the SSH may reflect and fulfill both purposes. The limited coverage of the SSH in Scopus and Web of Science is discussed along with ideas about how to achieve a more complete representation of all the languages and publication types that are actually used in the SSH. A dynamic and empirical concept of balanced multilingualism is introduced to support combined strategies for internationalization and societal interaction. The argument is that all the communication purposes in all different areas of research, and all the languages and publication types needed to fulfill these purposes, should be considered in a holistic manner without exclusions or priorities whenever research in the SSH is evaluated.

Open access

Karel Janečka

Abstract

The 3D geoinformation is becoming important for cities and their policies. The cities are therefore exploring the possibilities of 3D virtual city models for more efficient decision making. To maximize the economic benefit of such data, the cities can provide their 3D geospatial data for further usage, and so, new applications can be created. The paper defines a way how the freely available 3D geospatial data of Prague can be transformed from the proprietary data format into the open data model. The 3D geospatial data about the buildings, bridges and digital terrain model were transformed from the 3D shapefile into the CityGML. This is an application independent information model and exchange format. This will allow for the wider use of the 3D city model by different groups of users. The generated CityGML files were further imported into the spatial database with appropriate database CityGML-based scheme. It enables more efficient management and querying of CityGML data. To enable the wider audience to explore the 3D city model, the visualization in the web environment was also explored. The paper also presents the way how the attributes from the external data sources can be connected to the 3D objects in the web environment.

Open access

Zbigniew Szczerbowski

Abstract

Seismic events in the area of Poland are related mostly to copper and coal mining, and they are regarded as the most dangerous natural hazard. Although development of geomechanical modelling as the development of geophysical methods determining seismic hazard are evident, low predictability of the time-effect relationship still remains. Geomechanical models as geophysical data analysis highlight the interaction between parts of rock mass or allow to reconstruct the way of rock mass destruction and to understand the processes that take place in the high-energy tremors.

However, the association of larger mining tremors with pre-existing geological features has been reported by many investigators; in geomechanical practice, investigations of rock mass condition concentrate on this problem in the local scale. Therefore, the problem of relations between high-energy seismic events in Legnica–Głogów Copper District (LGCD) and regional scale deformations of terrain surface resulting from possible tectonic activity is discussed in this paper. The GNSS data evaluated from the observations of ASG-EUPOS (Active Geodetic Network – EUPOS) stations in the area of LGCD and in the adjacent areas is analysed in this study. Temporal variation of distances between the stations and evaluated on that base so called apparent strain was combined with the occurrence of high-energy tremors. Consequently, after the examination and analysis of occurrences of mining tremors, it is found that high-energy seismic events and periods of strain accumulation evaluated from GPS/GNSS data have temporal relations. Although the seismic events were triggered by mining, nearly all the events with energy E > 108 J occurred in the periods when the analysed stations’ positions demonstrated a decrease in the baseline length.

Open access

Cihan Altuntas

Abstract

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

Open access

Tolga Yuret

Abstract

A prevalent belief is that it is advantageous to have surname initials that are placed early in the alphabet (early surname initials) in academic fields in which authors are ordered alphabetically (alphabetic academic fields), because first authors are more visible. However, it is not certain that the advantage is strong enough to affect academic careers. In this paper, the advantage in having such early surname initials is analyzed by using data from 1,345 course catalogs that span a 100 years. We obtained academic titles and surname initials of 19,353 faculty members who appeared 211,816 times in these course catalogs. Two alphabetic academic fields – economics and mathematics – and four other academic fields that are not alphabetic were analyzed. We found that there are some years when faculty members who have early surname initials are more likely to be full professors. However, there are many other years when faculty members who have early surname initials are less likely to be full professors. We also analyzed the career path of each faculty member. Economists who have early surname initials are found to be more likely to become full professors. However, this result is not significant and does not extend to mathematicians.

Open access

Volodymyr Hlotov, Alla Hunina, Mariana Yurkiv and Zbigniew Siejka

Abstract

Currently, UAVs are intensively being introduced into topographic-photogrammetric production for topographic digital aerial photography and laser scanning. These technologies have a number of advantages: they don’t require specially prepared platforms and launchers, they are relatively inexpensive unlike large aircrafts, and they are safe. However, there are still many unsolved problems for ultralight UAVs, especially when the aerial photography is made. As you know, the requirements for the implementation of the aerial survey process are quite stringent, first of all, for horizontal flight: the angles of inclination must be within 3–5 degrees, since exceeding these tolerances significantly affects the accuracy for determining the spatial coordinates of objects. Therefore, there was an idea to conduct researches of dependences between the pitch α, roll ω and yaw κ. For this purpose, 100 images obtained from aircraft-type UAV ‘Arrow’ developed and created by specialists from Lviv Polytechnic National University and ‘Abris’ were used. As a result of the study, the multiple correlation coefficient and the parameters of the linear regression equation for the angular elements of the exterior orientation of digital images were calculated. In addition, statistical quality evaluations for the obtained regression model were carried out. Analysis of the received data allows to assert that angular elements of exterior orientation are correlated with each other. Therefore, in the further imaging materials, processing it becomes possible to make compensation of this fact and to improve calculation accuracy of spatial coordinates of points.

Open access

Volodymyr Litynskyi, Svyatoslav Litynskyi, Anatolii Vivat, Mykhailo Fys and Andrii Brydun

Abstract

Modern scanners can perform terrestrial topographic survey with resolution of 1 cm and accuracy of 2 mm in just a few minute‘s time, from the distance of up to 100 meters. However, for surface topographical surveying of large territories or complex industrial objects, it is necessary to conduct geodetic traverses and perform their binding to the points of the geodesic basis. One method of coordinate transferring during surveying is by using the method of inverse linear-angular intersection, which involves the measuring of the respective sides S 1, S 2 and the β angle between them. This method is more precise than the classical one, which usually contains centring and reduction errors. The linear-angular intersection method can also be used for many applications in engineering geodesy, for laying geodetic traverses, and for binding to the wall based points of ground-surveying.