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Application of terrestrial laser scanning to the development and updating of the base map

Przemysław Klapa Bartosz Mitka
Geodesy and Cartography | 2017 | vol. 66 | No 1 | DOI: 10.1515/geocart-2017-0002
Keywords base map terrestrial laser scanning cartographic material
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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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Authors and Affiliations

Przemysław Klapa
Bartosz Mitka

Mobile Laser Scanning accuracy assessment for the purpose of base-map updating

Anna Fryskowska Patryk Wróblewski
Geodesy and Cartography | 2018 | vol. 67 | No 1
Keywords mobile Laser Scanning base-map data accuracy
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Abstract

The aim of the research was to analyze the possibility of using mobile laser scanning systems to acquire information for production and/or updating of a basic map and to propose a no-reference index of this accuracy assessment. Point clouds have been analyzed in terms of content of interpretation and geometric potential. For this purpose, the accuracy of point clouds with a georeference assigned to the base map objects was examined. In order to conduct reference measurements, a geodetic network was designed and also additional static laser scanning data has been used. The analysis of mobile laser scanning (MLS) data accuracy was conducted with the use of 395 check points. In the paper, application of the total Error of Position of the base-map Objects acquired with the use of MLS was proposed. Research results were related to reference total station measurements. The resulting error values indicate the possibility to use an MLS point cloud in order to accurately determine coordinates for individual objects for the purposes of standard surveying studies, e.g. for updating some elements of the base map content. Nevertheless, acquiring MLS point clouds with satisfying accuracy not always is possible, unless specific resolution condition is fulfilled. The paper presents results of accuracy evaluation in different classes of base-map elements and objects.
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Authors and Affiliations

Anna Fryskowska
Patryk Wróblewski

Advantages of Using 3D Scanning in the Survey of Architectural Monuments on example of Archeological Sites in Egypt and Russia

Wojciech Terlikowski Martyna Gregoriou-Szczepaniak Ewa Sobczyńska Kacper Wasilewski
Archives of Civil Engineering | 2021 | vol. 67 | No 1 | 189-201 | DOI: 10.24425/ace.2021.136468
Keywords laser scanning Archaeological Heritage Masonry Structures
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Abstract

Every conservation works related to an ancient masonry structures should be preceded by an appropriate diagnostic. This should be understood as geometrical survey and various tests, which results with a proper analysis of the structure, identification of materials, technologies and techniques used during construction. The effective tool which could be used in this field is 3-D laser scanning. The digital image obtained as a result of scanning could be a proper base for a preservation programme, as well as help for creation of a precise digital models for a structural analysis. The examples of 3-D laser scanning application presented in the article are diagnostic works carried by the Division of Fundamentals of Building, Warsaw University of Technology, with the cooperation of Warsaw University, at the archaeological sites in Alexandria, Egypt and in Tanais, Rostov, Russia. Based on this works some most important advantages of laser scanning in identification, diagnostics and preservation of ancient architectural monuments was stated.
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Authors and Affiliations

Wojciech Terlikowski
1
ORCID: ORCID
Martyna Gregoriou-Szczepaniak
1
ORCID: ORCID
Ewa Sobczyńska
1
ORCID: ORCID
Kacper Wasilewski
1
ORCID: ORCID
  1. Warsaw University of Technology, Faculty of Civil Engineering, Amii Ludowej 16, 00-637 Warsaw, Poland

Selected aspects of data harmonization from terrestrial laser scanning

Janina Zaczek-Peplinska Maria Elżbieta Kowalska Edward Nowak
Archives of Civil Engineering | 2022 | vol. 68 | No 3 | 429-445 | DOI: 10.24425/ace.2022.141895
Keywords data harmonization intensity terrestrial laser scanning
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Abstract

Periodic inventory and check surveys of the surfaces in engineering structures using terrestrial laser scanning require performing scans from many locations. The survey should be planned so as to obtain full coverage of the measured surface with a point cloud of appropriate density. Due to a variety of terrain obstacles in the close vicinity of the surveyed structure, structural and technical elements, as well as machinery and construction equipment (whose removal is impossible e.g. because of their role in the building and protection of the structure), it is often necessary to combine scans acquired from locations having different measurement geometry of the scene and performed in different lighting conditions. This makes it necessary to fill in blank spots with data of different spectral and geometric quality. This paper presents selected aspects of data harmonization in terrestrial laser scanning. The laser beam incidence angle and the scanning distance are assumed as parameters affecting the quality of the data. Based on the assumed minimum parameters for spectral data, an example of a harmonizing function for the concrete surface of a slurry wall was determined, and the methodology for determining its parameters was described. The presented solution for spectral data harmonization is based on the selection of reference fields representative of a given surface, and their classification with respect to selected geometric parameters of the registered point cloud. For geometric data, possible solutions to the harmonization problem have been analyzed, and criteria for point cloud reduction have been defined in order to obtain qualitatively consistent data. The presented results show that harmonization of point clouds obtained from different stations is necessary before their registration, in order to increase the reliability of analyses performed on the basis of check survey results in the assessment of the technical condition of a surface, its deformation, cracks and scratches.
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Authors and Affiliations

Janina Zaczek-Peplinska
1
ORCID: ORCID
Maria Elżbieta Kowalska
1
ORCID: ORCID
Edward Nowak
1
ORCID: ORCID
  1. Warsaw University of Technology, Faculty of Geodesy and Cartography, Politechniki 1, 00-661 Warsaw, Poland

Implementation of GPR and TLS Data for the Assessment of the Bridge Slab Geometry and Reinforcement

S. Cafiso A. Di Graziano D. Goulias M. Mangiameli G. Mussumeci
Archives of Civil Engineering | Vol. 66 | No 1 | 297-308 | DOI: 10.24425/ace.2020.131789
Keywords Ground Penetrating Radar Terrestrial Laser Scanning Sicily
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Abstract

This paper presents a suggested approach for forensic investigation of bridge decks in which Ground penetrating radar (GPR) consisting of two antennas is used to assess the current conditions. The methodology was tested on a bridge deck in central Sicily. The acquired data were analyzed for identifying the asphalt overlay thickness, concrete cover depth and deck thickness and location of the rebar reinforcement. In the proposed approach for assessing bridge deck conditions the GPR survey was complemented with (i) a site investigation on layer thicknesses for calibration/verification purposes of the GPR response and (ii) a Terrestrial Laser Scanning system (TLS) to verify the bridge design slab curvature. The study shows that this methodology has significant merits on accurately assessing such bridge deck components when bridge design records are non-existing, and by using non-invasive methods such as laser scanning and GPR. The great advantage provided by the TLS technique is the possibility to obtain a 3D output model of the scanned element with the accuracy of the best topographic instruments in order to complement GPR data surveys for bridge inspection.

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Authors and Affiliations

S. Cafiso
A. Di Graziano
D. Goulias
M. Mangiameli
G. Mussumeci

Wavelet based buildings segmentation in airborne laser scanning data set

Wolfgang Keller Andrzej Borkowski
Geodesy and Cartography | 2011 | vol. 60 | No 2 | DOI: 10.2478/v10277-012-0010-0
Keywords wavelet airborne laser scanning segmentation multi-resolution analysis
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Abstract

In the recent years three-dimensional buildings modelling based on an raw air- borne laser scanning point clouds, became an important issue. A significant step towards 3D modelling is buildings segmentation in laser scanning data. For this purpose an algorithm, based on the multi-resolution analysis in wavelet domain, is proposed in the paper. The proposed method concentrates only on buildings, which have to be segmented. All other objects and terrain surface have to be removed. The algorithm works on gridded data. The wavelet-based segmentation proceeds in the following main steps: wavelet decomposition up to appropriately chosen level, thresholding on the chosen and adjacent levels, removal of all coefficients in the so-called influence pyramid and wavelet reconstruction. If buildings on several scaling spaces have to be segmented, the procedure should be applied iteratively. The wavelet approach makes the procedure very fast. However, the limitation of the proposed procedure is its scale-based distinction between objects to be segmented and the rest.
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Authors and Affiliations

Wolfgang Keller
Andrzej Borkowski

The two-stage filtering of airborne laser data in a frequency domain

Urszula Marmol
Geodesy and Cartography | 2010 | vol. 59 | No 2 | DOI: 10.2478/v10277-012-0003-z
Keywords laser scanning terrain surface algorithms automation filtering FFT
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Abstract

In the paper a frequency method of filtering airborne laser data is presented. A number of algorithms developed to remove objects above a terrain (buildings, vegetation etc.) in order to obtain the terrain surface were presented in literature. Those all methods published are based on geometrical criteria, i.e. on a specific threshold of elevation differences between two neighbouring points or groups of points. In other words, topographical surface is described in a spatial domain. The proposed algorithm operates on topographical surface described in a frequency domain. Two major tools, i.e. Fast Fourier Transform (FFT) and digital filters are used. The principal assumption is based on the idea that low frequencies are responsible for a terrain surface, while high frequencies are connected to objects above the terrain. The general guidelines of this method were for the first time presented at (Marmol and Jachimski, 2004). Due to the fact that the preliminary results showed some limitations, two-stage filtering algorithm has been introduced. The frequency filter was modified in such a manner that different filter parameters are used to detect buildings than those to recognize vegetation. In the first stage of data processing the filtering concerning elimination of points connected with urban areas was applied. The low-pass filter with parameters determined for urban area was used for the whole tested terrain in that stage. The purpose of the second stage was to eliminate vegetation by using the filter for forest areas. The presented method was tested by using data sets obtained in the ISPRS test on extracting DTM from point clouds. The results of using the two-stage algorithm were com- pared with both reference data and with filtering results of eight method reported to ISPRS test. A numerical comparison of the filter output with a reference data set shows that the filter generates DTM of a satisfactory quality. The accuracy of DTM produced by the frequency algorithm fits the average accuracy of eight methods reported in the ISPRS test.
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Authors and Affiliations

Urszula Marmol

Reliability of geodetic control measurements of high dams as a guarantee of safety of the construction and the natural environment

J. Zaczek-Peplinska K. Podawca K. Karsznia
Bulletin of the Polish Academy of Sciences Technical Sciences | 2018 | 66 | No 1 | 87-98
Keywords terrestrial laser scanning technical control of dams environmental safety
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Authors and Affiliations

J. Zaczek-Peplinska
K. Podawca
K. Karsznia

Comparison of Photgrammetric Techniques for Surface Reconstruction from Images to Reconstruction from Laser Scanning

Krzysztof Skabek Agnieszka Tomaka
Theoretical and Applied Informatics | 2014 | vol. 26 | No 3-4 | 159-176
Keywords photogrammmetric 3D reconstruction laser scanning mesh comparison
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Abstract

The techniques of photogrammetric reconstruction were compared to the laser scanning in the article. The different conditions and constraints were introduced for reconstructed images, e.g. different materials, lighting condition, camera resolution, number of images in the sequence or using a-pripori calibration. The authors compare the results of surface reconstruction using software tools avaliable for photogrammetric reconstruction. The analysis is preformed for the selected objects with regard to laserscanned models or mathematical models.

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Authors and Affiliations

Krzysztof Skabek
Agnieszka Tomaka

Absolute M split estimation as an alternative for robust M-estimation

Robert Duchnowski Patrycja Wyszkowska
Advances in Geodesy and Geoinformation | 2022 | vol. 71 | No 1 | e17 | DOI: 10.24425/gac.2022.141170
Keywords laser scanning robust estimation M-estimation absolute Msplit estimation
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Abstract

The problem of outlying observations is very well-known in the surveying data processing. Outliers might have several sources, different magnitudes, and shares within the whole observation set. It means that it is not possible to propose one universal method to deal with such observations. There are two general approaches in such a context: data cleaning or robust estimation. For example, the robust M-estimation has found many practical applications. However, there are other options, such as R-estimation or the absolute M split estimation. The latter method was created to be less sensitive to outliers than the squared M split estimation (the basic variant of Msplit estimation). From the theoretical point of view, the absolute M split estimation cannot be classified as a robust method; however, it was proved that it could be used in such a context under certain conditions. The paper presents the primary comparison between that method and a conventional robust M-estimation. The results show that the absolute M split estimation predominates over the classical methods, especially when the percentage of outliers is high. Thus, that method might be used to process LiDAR data, including mismeasured points. Processing synthetic data from terrestrial laser scanning or airborne laser scanning confirms that the absolute M split / estimation can deal with outliers sufficiently.
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Authors and Affiliations

Robert Duchnowski
1
ORCID: ORCID
Patrycja Wyszkowska
1
ORCID: ORCID
  1. University of Warmia and Mazury, Olsztyn, Poland

Forest succession mapping for post-agricultural areas using Sentinel-2, PlanetScope imageries and LiDAR data

Marta Szostak
Advances in Geodesy and Geoinformation | 2022 | vol. 71 | No 2 | e30 | DOI: 10.24425/agg.2022.141917
Keywords image processing secondary forest succession airborne laser scanning spatial analysis
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Abstract

The research investigates the possibility of applying Sentinel-2, PlanetScope satellite imageries, and LiDAR data for automation of land cover mapping and 3D vegetation characteristics in post-agricultural areas, mainly in the aspect of detection and monitoring of the secondary forest succession. The study was performed for the tested area in the Biskupice district (South of Poland), as an example of an uncontrolled forest succession process occurring on post-agricultural lands. The areas of interest were parcels where agricultural use has been abandoned and forest succession has progressed. This paper indicates the possibility of automating the process of monitoring wooded and shrubby areas developing in post-agricultural areas with the help of modern geodata and geoinformation methods. It was verified whether the processing of Sentinel-2, PlanetScope imageries allows for reliable land cover classification as an identification forest succession area. The airborne laser scanning (ALS) data were used for deriving detailed information about the forest succession process. Using the ALS point clouds vegetation parameters i.e., height and canopy cover were determined and presented as raster maps, histograms, or profiles. In the presented study Sentinel-2, PlanetScope imageries, and ALS data processing showed a significant differentiation of the spatial structure of vegetation. These differences are visible in the surface size (2D) and the vertical vegetation structure (3D).
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Authors and Affiliations

Marta Szostak
1
ORCID: ORCID
  1. University of Agriculture in Krakow, Krakow, Poland

MEMS mirror based eye tracking: simulation of the system parameter effect on the accuracy of pupil position estimation

Mateusz Pomianek Marek Piszczek Marcin Maciejewski
Metrology and Measurement Systems | 2021 | vol. 28 | No 4 | 711-724 | DOI: 10.24425/mms.2021.137704
Keywords eye tracking MEMS mirror laser scanning head-mounted display
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Abstract

Eye tracking systems are mostly video-based methods which require significant computation to achieve good accuracy. An alternative method with comparable accuracy but less computational expense is 2D microelectromechanical (MEMS) mirror scanning. However, this technology is relatively new and there are not many publications on it. The purpose of this study was to examine how individual parameters of system components can affect the accuracy of pupil position estimation. The study was conducted based on a virtual simulator. It was shown that the optimal detector field of view (FOV) depends on the frequency ratio of the MEMS mirror axis. For a value of 1:13, the smallest errors were at 0.°, 1.65°, 2.3°, and 2.95°. The error for the impact of the signal sampling rate above 3 kHz stabilizes at 0.065° and no longer changes its value regardless of increasing the number of samples. The error for the frequency ratio of the MEMS mirror axis increases linearly in the range of 0.065°–0.1°up to the ratio of 1:230. Above this there is a sudden increase to the average value of 0.3°. The conducted research provides guidance in the selection of parameters for the construction of eye tracking MEMS mirror-based systems.
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Bibliography

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[17] Pomianek, M., Piszczek, M., Maciejewski, M., & Krukowski, P. (2020, October). Pupil Position Estimation Error in an Eye Tracking System Based on the MEMS Mirror Scanning Method. Proceedings of the 3rd International Conference on Microelectronic Devices and Technologies (MicDAT’ 2020) (pp. 28–30). IFSA.
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Authors and Affiliations

Mateusz Pomianek
1
Marek Piszczek
1
Marcin Maciejewski
1
  1. Military University of Technology, Institute of Optoelectronics, 2 Kaliskiego St., 00-908 Warsaw, Poland

Accuracy of merging point clouds at the maximum range of a scanner with limited possibilities of target placement

G. Lenda P. Lewińska J. Siwiec
Archives of Civil Engineering | 2019 | Vol. 65 | No 4 | 229-248
Keywords laser scanning long range targets registration accuracy point cloud
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Abstract

The research was aimed at analysing the factors that affect the accuracy of merging point clouds when scanning over longer distances. Research takes into account the limited possibilities of target placement occurring while scanning opposite benches of quarries or open-pit mines, embankments from opposite banks of rivers etc. In all these cases, there is an obstacle/void between the scanner and measured object that prevents the optimal location of targets and enlarging scanning distances. The accuracy factors for cloud merging are: the placement of targets relative to the scanner and measured object, the target type and instrument range. Tests demonstrated that for scanning of objects with lower accuracy requirements, over long distances, it is optimal to choose flat targets for registration. For objects with higher accuracy requirements, scanned from shorter distances, it is worth selecting spherical targets. Targets and scanned object should be on the same side of the void.

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Authors and Affiliations

G. Lenda
P. Lewińska
J. Siwiec

3D modeling of architectural objects from video data obtained with the fixed focal length lens geometry

Paulina Deliś Michał Kędzierski Anna Fryśkowska Michalina Wilińska
Geodesy and Cartography | 2013 | vol. 62 | No 2 | DOI: 10.2478/geocart-2013-0007
Keywords video image image orientation bundle adjustment terrestrial laser scanning 3D modeling
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Abstract

The article describes the process of creating 3D models of architectural objects on the basis of video images, which had been acquired by a Sony NEX-VG10E fixed focal length video camera. It was assumed, that based on video and Terrestrial Laser Scanning data it is possible to develop 3D models of architectural objects. The acquisition of video data was preceded by the calibration of video camera. The process of creating 3D models from video data involves the following steps: video frames selection for the orientation process, orientation of video frames using points with known coordinates from Terrestrial Laser Scanning (TLS), generating a TIN model using automatic matching methods. The above objects have been measured with an impulse laser scanner, Leica ScanStation 2. Created 3D models of architectural objects were compared with 3D models of the same objects for which the self-calibration bundle adjustment process was performed. In this order a PhotoModeler Software was used. In order to assess the accuracy of the developed 3D models of architectural objects, points with known coordinates from Terrestrial Laser Scanning were used. To assess the accuracy a shortest distance method was used. Analysis of the accuracy showed that 3D models generated from video images differ by about 0.06 ÷ 0.13 m compared to TLS data.
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Authors and Affiliations

Paulina Deliś
Michał Kędzierski
Anna Fryśkowska
Michalina Wilińska

The optimal position of a pumping station based on the digital terrain model

Marian Poniewiera Iwona Jelonek Wioleta Błaszczak-Bąk
Journal of Water and Land Development | 2019 | No 40
Keywords AutoCAD Civil Digital Terrain Model, laser scanning, mining surface deformation
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Authors and Affiliations

Marian Poniewiera
Iwona Jelonek
Wioleta Błaszczak-Bąk

Defining the Computational Domain and Boundary Conditions for Fluid Flow in a Mining Excavation

Jakub Janus Jerzy Krawczyk
Archives of Mining Sciences | 2023 | vol. 68 | No 3 | 425-441 | DOI: 10.24425/ams.2023.146860
Keywords CFD mine ventilation numerical model geometry laser scanning velocity profile boundary conditions
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Abstract

For underground mine workings, the shape of the computational domain may be difficult to define. Historically, the geometry models of mine drifts were not accurate representations of the object but rather a simplified approximation. To fully understand a phenomenon and save time on computations, simplification is often required. Nevertheless, in some situations, a detailed depiction of the geometry of the object may be necessary to obtain adequate simulation results. Laser Scanning enables the generation of 3D digital models with precision beyond the needs of applicable CFD models. Images composed of millions of points must be processed to obtain geometry suitable for computational mesh generation. A section of an underground mine excavation has been selected as an example of such transformation. Defining appropriate boundary conditions, especially the inlet velocity profile, is a challenging issue. Difficult environmental conditions in underground workings exclude the application of the most efficient and precise methods of velocity field measurements. Two attempts to define the inlet velocity profile have been compared. The first one used a sequence of simulations starting from a flat profile of a magnitude equal to the average velocity. The second one was based on the sixteen-point simultaneous velocity measurement, which gave consistency with measurement results within the range of applied velocity measurement method uncertainty. The article introduces a novel methodology that allows for more accurate replication of the mine excavation under study and the attainment of an appropriate inlet velocity profile, validated by a satisfactory correspondence between simulation outcomes and field measurements. The method involves analysing laser-scanned data of a mine excavation, conducting multi-point velocity measurements at specific cross-sections of the excavation that are unique to mining conditions, and utilising the k-ω SST turbulence model that has been validated for similar ventilation problems in mines.
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Authors and Affiliations

Jakub Janus
1
ORCID: ORCID
Jerzy Krawczyk
1
ORCID: ORCID
  1. Strata Mechanics Research Institutes of Polish Academy of Science, 27 Reymonta Str., 30-059 Kraków, Poland

In-situ Observation of High-Temperature Fracture Behaviour of 347 Stainless Steel Subjected to Simulated Welding Process

Seok-Woo Ko Hyeonwoo Park Il Yoo Hansoo Kim Joonho Lee Byoungchul Hwang
Archives of Metallurgy and Materials | 2021 | vol. 66 | No 4 | 1019-1022 | DOI: 10.24425/amm.2021.136417
Keywords 347 stainless steel in-situ high temperature fracture behaviour welding confocal laser scanning microscope (CLSM)
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Abstract

In-situ study on the high-temperature fracture behaviour of 347 stainless steel was carried out by using a confocal laser scanning microscope (CLSM). The welding microstructures of the 347 stainless steel were simulated by subjecting the steel specimen to solution and aging treatments. Undissolved NbC carbides were present within grains after solution treatment, and M23C6 carbides were preferentially formed at grain boundaries after subsequent aging treatment. The M23C6 carbides formed at grain boundaries worked as stress concentration sites and thus generated larger cracks during high-temperature tensile testing. In addition, grain boundary embrittlement was found to be a dominant mechanism for the high-temperature fracture of the 347 stainless steel because vacancy diffusion in the Cr-depleted zones enhances intergranular fracture due to the precipitation of M23C6 carbides at grain boundaries.
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Bibliography

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Authors and Affiliations

Seok-Woo Ko
1
ORCID: ORCID
Hyeonwoo Park
2
ORCID: ORCID
Il Yoo
3
ORCID: ORCID
Hansoo Kim
2
ORCID: ORCID
Joonho Lee
2
ORCID: ORCID
Byoungchul Hwang
1
ORCID: ORCID
  1. Seoul National University of Science and Technology, Department of Materials Science and Engineering, 232 Gongneung-ro, Nowon-gu, Seoul 01811, Republic of Korea
  2. Korea University, Department of Materials Science and Engineering, Seoul 02841, Republic of Korea
  3. ADNOC LNG, Abu Dhabi, United Arab Emirates

Application of terrestrial laser scanning measurements for wind turbine blade condition surveying

Paulina Stałowska Czesławi Suchock Adam Zagubien
Metrology and Measurement Systems | 2023 | vol. 30 | No 3 | 403-422 | DOI: 10.24425/mms.2023.146419
Keywords Terrestrial Laser Scanning (TLS) intensity parameter measurement methodology wind turbine blades condition surveying defects detection
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Abstract

Wind turbines are among the key equipment needed for eco-friendly generation of electricity. Maintaining wind turbines in excellent technical condition is extremely important not only for safety but also for efficient operation. Studies indicate that defects in the external structure of a turbine blade reduce energy production efficiency. This research investigated the potential of the terrestrial laser scanning technology to examine the technical conditions of wind turbine blades. The main aim of the study was to examine whether terrestrial laser scanning measurements can be valuable for wind turbine blade condition surveying. The investigation was based on the radiometric analyses of point clouds, which forms the novelty of the present study. Condition monitoring focuses on the detection of defects, such as cracks, cavities, or signs of erosion. Moreover, this study consisted of two stages. The next objective entailed the development and examination of two different measurement methods. It was then identified which method is more advantageous by analysing their effectiveness and other economic considerations.
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Authors and Affiliations

Paulina Stałowska
1
Czesławi Suchock
2
Adam Zagubien
2
  1. Civil Engineering and Transport discipline, Doctoral School of the Koszalin University of Technology, Sniadeckich 2,75-453 Koszalin, Poland
  2. Faculty of Civil Engineering, Environmental and Geodetic Sciences, Koszalin University of Technology,Sniadeckich 2, 75-453 Koszalin, Poland

Calcium (Ca2+) expression and intensity in cumulus-oocyte complex (COCs) in Kacang goat after vitrification

W. Widjiati Z. Faizah N. Darsini V.F. Hendrawan H.N. Karima C. Chotimah S.B. Sumitro L.R. Yustinasari A.A.M.N. Kasman J.M. Ntoruru E.M. Luqman
Polish Journal of Veterinary Sciences | 2022 | vol. 25 | No 1 | 19-26 | DOI: 10.24425/pjvs.2022.140836
Keywords Calcium (Ca2+) confocal laser scanning microscope cumulus-oocyte complex (COCs) food production Kacang goat
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Abstract

The process of vitrification of the cumulus-oocyte complex (COCs) often results in cold shock. When warming, heat shock occurs which can disrupt the balance of intracellular calcium (Ca2+) intensity. Drastic changes in temperature cause Reactive Oxygen Species (ROS), affecting changes on Ca2+ in COCs. The role of calcium is needed for oocyte activation in the fertilization process. The purpose of this study was to measure the expression of Ca2+ and the intensity of Ca2+ in COCs after vitrification. The study was divided into 2 groups, the control group (C) of fresh COCs, and the treatment group (T) of COCs after vitrification. After vitrification for 24 hours, then thawing, the expression of Ca2+ was examined using the Immunocytochemistry (ICC) method and the intensity of calcium (Ca2+) with a Confocal Laser Scanning Microscope (CLSM). The research data obtained were analyzed statistically by T-Test. The results showed that the expression of Ca2+ in the control group (12.00±0.00) was different from the treatment group (0.35±0.79). The intensity of Ca2+ in the control group (1059.43±489.59) was different from the treatment group (568.21±84.31). The conclusion of this study is that cryopreservation affects calcium in COCs; there were differences in the expression and the intensity of Ca2+ between fresh COCs and COCs after vitrification. Ca2+ intensity of COCs after vitrification was concentrated in the nucleus, while in fresh COCs it was concentrated in the cytoplasm.
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Authors and Affiliations

W. Widjiati
1
Z. Faizah
2
N. Darsini
2
V.F. Hendrawan
3
H.N. Karima
4
C. Chotimah
4
S.B. Sumitro
5
L.R. Yustinasari
6
A.A.M.N. Kasman
7
J.M. Ntoruru
8
E.M. Luqman
6
  1. Post Graduate School of Universitas Airlangga Surabaya, Indonesia
  2. Department of Biomedical Science, Faculty of Medicine Universitas Airlangga Surabaya, Indonesia
  3. Department of Reproduction, Faculty of Veterinary Medicine, Universitas Brawijaya Malang, Indonesia
  4. Bio-Science Central Laboratory, Universitas Brawijaya Malang, Indonesia
  5. Department of Biology, Faculty of Science, Universitas Brawijaya Malang, Indonesia
  6. Department of Veterinary Science, Faculty of Veterinary Medicine, Universitas Airlangga Surabaya, Indonesia
  7. Faculty of Health Science, Universitas Muhammadiyah Mataram, Mataram, Indonesia
  8. Research Assistant, Meru University, Kenya

Multi-criteria diagnostics of historic buildings with the use of 3D laser scanning (a case study)

Anna Szymczak-Graczyk Zbigniew Walczak Barbara Ksit Zdzisław Szyguła
Bulletin of the Polish Academy of Sciences Technical Sciences | 2022 | 70 | 2 | e140373 | DOI: 10.24425/bpasts.2022.140373
Keywords laser scanning diagnostics historic buildings limit state method beam deflection mycological tests
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Abstract

The protection and use of historic buildings is a difficult and costly task. Most often, these objects are under conservatory protection and any interference in their structure requires appropriate consent. On the other hand, conducting construction works on historic buildings carries a high risk of their damage or even destruction. Therefore, proper prior diagnostics is an extremely important factor affecting the scope and manner of works to be conducted. The paper presents the use of 3D scanning to determine the deflection of the ceiling under the Column Hall of the historic Palace, the floor of which showed elasticity, recorded during changing service loads. After identifying the places with the greatest deflections, based on data from 3D laser scanning, test holes were made and wood samples from the ceiling were taken to perform moisture content and mycological tests. An endoscopic inspection camera was inserted into test holes, providing the basis for recognizing the structure of the ceiling, i.e. arrangement of layers as well as dimensions and spacing of ceiling beams. Strength calculations were made with the limit state method resulted in the determination of the maximum permissible service load on the ceiling. The presented course of action in diagnostics of the analysed historic building may be an example of a preliminary procedure to be taken before deciding on changes in the manner of use of historic buildings or the functionalities of their individual parts.
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Authors and Affiliations

Anna Szymczak-Graczyk
1
Zbigniew Walczak
1
Barbara Ksit
2
ORCID: ORCID
Zdzisław Szyguła
3
  1. Department of Construction and Geoengineering, Poznan University of Life Sciences, 60-637 Poznań, Poland
  2. Institute of Building Engineering, Poznan University of Technology, Piotrowo 5, 60-965 Poznań, Poland
  3. Company owner, Poland

In-Situ Observation of Acicular Ferrite Transformation in High-Strength Low-Alloy Steel Using Confocal Laser Scanning Microscopy

Sang-In Lee Seung-Hyeok Shin Hyeonwoo Park Hansoo Kim Joonho Lee Byoungchul Hwang
Archives of Metallurgy and Materials | 2022 | vol. 67 | No 4 | 1497-1501 | DOI: 10.24425/amm.2022.141081
Keywords acicular ferrite high-strength low-alloy steel confocal laser scanning microscopy (CLSM) phase transformation in-situ observation
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Abstract

In-situ observation of the transformation behavior of acicular ferrite in high-strength low-alloy steel using confocal laser scanning microscopy was discussed in terms of nucleation and growth. It is found that acicular ferrite nucleated at dislocations and slip bands in deformed austenite grains introduced by hot deformation in the non-recrystallization austenite region, and then proceeded to grow into an austenite grain boundary. According to an ex-situ EBSD analysis, acicular ferrite had an irregular shape morphology, finer grains with sub-grain boundaries, and higher strain values than those of polygonal ferrite. The fraction of acicular ferrite was affected by the deformation condition and increased with increasing the amount of hot deformation in the non-recrystallization austenite region.
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Authors and Affiliations

Sang-In Lee
1
ORCID: ORCID
Seung-Hyeok Shin
1
ORCID: ORCID
Hyeonwoo Park
2
ORCID: ORCID
Hansoo Kim
2
ORCID: ORCID
Joonho Lee
2
ORCID: ORCID
Byoungchul Hwang
1
ORCID: ORCID
  1. Seoul National University of Science and Technology, Department of Materials Science and Engineering, Seoul, 01811, Republic of Korea
  2. Korea University, Department of Materials Science and Engineering, Seoul, 02841, Republic of Korea

Large Scale Architectural Glass Slumping Process – Chalenges and Limitations

Andrzej Malewski Marcin Kozłowski Wojciech Sumelka Marek Połedniok
Archives of Civil Engineering | Vol. 66 | No 4 | 485-505 | DOI: 10.24425/ace.2020.135233
Keywords glass formation curved glass modern architecture glass production laser scanning glass behaviour
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Abstract

The paper focuses on the development of knowledge about the hot bending of curved architectural glass produced by the slumping process and the challenges as well as the limitations thereof. Due to the complexity of the process, many factors influence the final quality of the glass and the main objective was to better understand the procedure itself in order to improve the control and quality of the slumping process. As a result of the growing interest in this type of glass for architectural applications, the glass processing market is increasingly investing in the required technology. For the moment, this growing niche does not have a large number of direct explanations of the glass behaviour in the furnace in the available literature, which in turn encourages cooperation between the scientific community and manufacturers. This paper presents the conducted experiments that have led to a better understanding of the furnace's work and the impact of specific factors on its operation. Based on the 3D numerical model, a large sample of glass was produced, which was then scanned with a 3D laser using a method developed for the experiment. The results suggested that a more accurate test with usage of a full-size furnace is required. Based on this, the experiment was carried out using a large number of glass samples of different thicknesses. The results of the experiment helped to better understand and demonstrate the need for further research of this technology in order to optimize the quality of the process.

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Authors and Affiliations

Andrzej Malewski
Marcin Kozłowski
Wojciech Sumelka
Marek Połedniok

3D modelling with the use of photogrammetric methods

Izabela Piech Tomasz Adam Paulina Dudas
Archives of Civil Engineering | 2022 | vol. 68 | No 3 | 481-500 | DOI: 10.24425/ace.2022.141898
Keywords 3D modelling visualization terrestrial laser scanning unmanned aerial vehicles nonmetric cameras
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Abstract

Extremely intensive development of technology has resulted in many innovations. There are new methods of acquiring spatial data, such as laser scanning, unmanned aerial vehicles or digital non-metric cameras, which are the subject of this study. Integration of this data has become a new tool that has expanded existing measurement capabilities, finding applications in 3D modelling, archaeology and monument conservation. Owing to scanning, we can get the coordinates of almost every point of the scanned surface, obtaining full and detailed information about the object dimensions. The level of technical advancement of digital cameras allows them to be successfully used in short-range photogrammetry [27], and recently also in low-altitude aerial photogrammetry (unmanned aerial vehicles). Two different test objects were selected to achieve the intended purpose. The monument located on the 14-meter-high top of the Wanda Mound was adopted as the first object. It consists of a simple rectangular plinth made of brown marble. On its top there is a figure of an eagle with a crown of white marble. On the west wall of the plinth there is an inscription “Wanda” and a drawing showing a sword crossed with a distaff. The following features supported the choice of the monument: interesting shape of the object, which includes both simple geometric forms with large and flat surfaces (plinth), and more detailed surfaces (figure of an eagle); detailed texture of the object (complicated marble veins, wing details). The second object under study was The Helena Modrzejewska National Stary Theatre. The building was rebuilt in the style of Viennese Art Nouveau, so that it fully incorporates into the rest of buildings. Measurements included data obtained from a non-metric camera, Leica ScanStation scanner and DJI S 1000 multi-rotor.
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Authors and Affiliations

Izabela Piech
1
ORCID: ORCID
Tomasz Adam
2
Paulina Dudas
2
  1. Krakow University of Agriculture, Faculty of Environmental Engineering and Land Surveying, Al. Mickiewicza 24/28, 30-059 Krakow, Poland
  2. Graduate of the University of Agriculture in Krakow, Faculty of Environmental Engineering and Land Surveying, Al.Mickiewicza 24/28, 30-059 Krakow, Poland

Determining the trend of geometrical changes of a hydrotechnical object based on data in the form of LiDAR point clouds

Maria Kowalska Janina Zaczek-Peplinska Łukasz Piasta
Archives of Civil Engineering | 2024 | vol. 70 | No 1 | 305-323 | DOI: 10.24425/ace.2024.148913
Keywords LiDAR normal vectors point clouds terrestrial laser scanning deformations of hydrotechnical structures cluster algorithm
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Abstract

Monitoring the technical condition of hydrotechnical facilities is crucial for ensuring their safe usage. This process typically involves tracking environmental variables (e.g., concrete damming levels, temperatures, piezometer readings) as well as geometric and physical variables (deformation, cracking, filtration, pore pressure, etc.), whose long-term trends provide valuable information for facility managers. Research on the methods of analyzing geodetic monitoring data (manual and automatic) and sensor data is vital for assessing the technical condition and safety of facilities, particularly when utilizing new measurement technologies. Emerging technologies for obtaining data on the changes in the surface of objects employ laser scanning techniques (such as LiDAR, Light Detection, and Ranging) from various heights: terrestrial, unmanned aerial vehicles (UAVs, drones), and satellites using sensors that record geospatial and multispectral data. This article introduces an algorithm to determine geometric change trends using terrestrial laser scanning data for both concrete and earth surfaces. In the consecutive steps of the algorithm, normal vectors were utilized to analyze changes, calculate local surface deflection angles, and determine object alterations. These normal vectors were derived by fitting local planes to the point cloud using the least squares method. In most applications, surface strain and deformation analyses based on laser scanning point clouds primarily involve direct comparisons using the Cloud to Cloud (C2C) method, resulting in complex, difficult-to-interpret deformation maps. In contrast, preliminary trend analysis using local normal vectors allows for rapid threat detection. This approach significantly reduces calculations, with detailed point cloud interpretation commencing only after detecting a change on the object indicated by normal vectors in the form of an increasing deflection trend. Referred to as the cluster algorithm by the authors of this paper, this method can be applied to monitor both concrete and earth objects, with examples of analyses for different object types presented in the article.
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Authors and Affiliations

Maria Kowalska
1
ORCID: ORCID
Janina Zaczek-Peplinska
1
ORCID: ORCID
Łukasz Piasta
1
  1. Warsaw University of Technology, Faculty of Geodesy and Cartography, pl. Politechniki 1, 00-661 Warsaw, Poland

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