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In recent years, 3D digitalisation has experienced significant growth, revolutionising the way we capture, process and use geometric data. Initially conceived for industrial applications, these technologies have expanded to multiple fields, offering unprecedented accuracy and versatility. Depending on the accuracy and efficiency to be achieved in a specific field of application, and on the analytical capacity, a specific 3D digitalisation technique or another will be used. This review aims to delve into the application of 3D scanning techniques, according to the implementation sector. The optimal geometry capturing and processing 3D data techniques for a specific case are studied as well as their limitations.

Bloodstain pattern analysis (BPA) has proven to be a useful tool in forensic and criminal investigations for quite some time. Traditionally, documenting a crime scene for a bloodletting event was completed using manual techniques, physical strings, and a tape measure. In more recent years, laser scanners and 3D software programs have become a preferred method to capture accurate data that improves the validity and reliability of BPA. The initial cost of laser scanning equipment is relatively high, rendering these systems inaccessible to some police and smaller agencies. Recon-3D is a newly developed iPhone application that utilizes the iPhone LiDAR sensor in combination with video data to create 3D point clouds of crime scenes. To assess the viability of Recon-3D for area of origin analysis, two tests were performed. One was a series of bloodstain impacts which were analyzed in FARO Zone 3D software, while the second was a series of 6 repeated Recon-3D scans of two 90-degree walls which was then compared to the FARO Focus S350 scanner using CloudCompare software. A total of eight impact patterns were made at three different distances from a wall. The area of origin was measured and compared to the known location of the blood source. The average total 3D error for the area of origin set at 25, 50, and 100 cm from two perpendicular walls was found to be 6.04, 15.16, and 36.59 cm, respectively. These results are similar to past studies where programs such as HemoSpat have been used. The results of the point cloud comparison show that on average, 95% of the points from Recon-3D fall below a threshold of 3.6 mm when compared to a FARO Focus S350 laser scanner. Thus, the results of this test suggest that Recon-3D is an accurate and affordable scanning application for bloodstain patterns at crime scenes and the data provide acceptable results for area of origin analysis in BPA programs which accept laser scanner data. [ABSTRACT FROM AUTHOR]

The selection of the optimal methodology for the 3D geometric documentation of cultural heritage is a subject of high concern in contemporary scientific research. As a matter of fact, it requires a multi-source data acquisition process and the fusion of datasets from different sensors. This paper aims to demonstrate the workflow for the proper implementation and integration of geodetic, photogrammetric and laser scanning techniques so that high-quality photorealistic 3D models and other documentation products can be generated for a complicated, large-dimensional architectural monument and its surroundings. As a case study, we present the monitoring of the Mehmet Bey Mosque, which is a landmark in the city of Serres and a significant remaining sample of the Ottoman architecture in Greece. The surveying campaign was conducted in the context of the 2022–2023 annual workshop of the Interdepartmental Program of Postgraduate Studies "Protection Conservation and Restoration of Cultural Monuments" of the Aristotle University of Thessaloniki, and it served as a geometric background for interdisciplinary cooperation and decision-making on the monument restoration process. The results of our study encourage the fusion of terrestrial laser scanning and photogrammetric datasets for the 3D modeling of the mosque, as they supplement each other as regards geometry and texture. [ABSTRACT FROM AUTHOR]

The use of composite plate structures has become increasingly prevalent in industries such as civil engineering, aerospace, high-speed rail, automotive, and wind power. However, the propagation of ultrasonic Lamb waves in these structures is subject to multi-modal and frequency dispersion effects, which, coupled with the complicated anisotropic propagation mechanism of composite materials, makes it challenging to extract damage scatter signals without a health signal as a reference. In this study, we apply the frequency-wavenumber (f - k) domain filter wavefront modal method to carbon fiber reinforced polymer (CFRP) materials and use a three-dimensional (3D) window function to achieve different modalities and their corresponding damage reflection signals in the absence of a reference dispersion curve. Single modal damage imaging is achieved using a common source method (CSM) by laser vibration scanning experiment. To effectively extract single modalities in laminate material damage detection, a 3D filter window function was constructed. Considering the skew angle correction, it can effectively remove the direct wave signal, so as to realize the imaging of the damage. [ABSTRACT FROM AUTHOR]

The variety of equipment implementing laser triangulation technology for 3D scanning makes it difficult to analyse their performance, comparability, and traceability. In this study, three laser triangulation sensors arranged in different configurations are analysed using high precision spheres made of different materials and surface finishes. Three types of reference parameters were used: diameter, form error, and standard deviation of the point cloud. The experimentation was based on studying the quality of the point clouds generated by the three sensors, which enabled us to find and quantify an edge effect in the horizon of the scanned surface. A procedure to reach the optimal filtering conditions was proposed, and a chart of recommended usage of each sphere (material and finish) was created for the different types of sensors. This filter enables removal of both spurious points and those few points that spoil the form error, greatly improving the quality of the measurement. [ABSTRACT FROM AUTHOR]

This paper discusses an experience developed as part of the 2021 Topographic Survey Workshop, organized by the Department of Cultural Heritage of Ravenna (University of Bologna) in the Roman city of Suasa (Castelleone di Suasa, AN), during which the potential of integrating photogrammetric and laser scanner surveys was explored in order to geometrically and morphologically characterize the remains of the Roman amphitheater. [ABSTRACT FROM AUTHOR]

The study presents advanced measurement methods used in the inventory of historic buildings, focused on the Potocki Palace in Krzeszowice. The paper addresses two main measurement methods that led to obtaining comprehensive and accurate documentation. The first technique was terrestrial laser scanning, using specialised laser scanners to collect data. In order to represent the actual colours and texture of the object under study, the scanning method was supported by photogrammetry. The second method was low-ceiling photogrammetry, which provided even more accurate data about the Palace. Data processing resulted in a three-dimensional (3D) solid, consisting of a multi-million-point cloud. This was followed by a vectorisation process, which made it possible to obtain a full-dimensional representation of the studied object. The results facilitated a detailed analysis of the Potocki Palace, including the identification of damage and changes occurring over the years. The resulting documentation provides a solid basis for future conservation, modernisation and research work related to the building. The paper also points out the potential applications of contemporary technologies in order to visualize inventoried objects. The technique of Virtual Reality (VR) and showing the object in 3D that has been popular so far, has recently found even broader application, providing input for the construction of the so-called Augmented Reality (AR). [ABSTRACT FROM AUTHOR]

Digital image processing is commonly used in civil engineering to measure aggregate morphologies. However, it has limitations due to laying style and acquisition method, restricting analysis to two-dimensional geometric features. To overcome this, a new laser scanning-based method is proposed to reconstruct three-dimensional features of coarse aggregates. Three-dimensional morphology indexes are developed, with promising results. This method effectively captures complete surface information and the ratios between axes, surface area rate, and volume rate describe shape, texture, and angularity well. The proposed methodology accurately characterizes coarse aggregate morphologies, aiding asphalt mixture design. Incorporating the developed indexes enables effective quality control of asphalt pavements. [ABSTRACT FROM AUTHOR]

[Display omitted] Thin-film sensors are essential for real-time monitoring of components in high-temperature environments. Traditional fabrication methods often involve complicated fabrication steps or require prolonged high-temperature annealing, limiting their practical applicability. Here, we present an approach using direct ink writing and laser scanning (DIW-LS) to fabricate high-temperature functional thin films. An indium tin oxide (ITO)/preceramic polymer (PP) ink suitable for DIW was developed. Under LS, the ITO/PP thin film shrank in volume. Meanwhile, the rapid pyrolysis of PP into amorphous precursor-derived ceramic (PDC) facilitated the faster sintering of ITO nanoparticles and improved the densification of the thin film. This process realized the formation of a conductive network of interconnected ITO nanoparticles. The results show that the ITO/PDC thin film exhibits excellent stability, with a drift rate of 4.7 % at 1000 °C for 25 h, and withstands temperatures up to 1250 °C in the ambient atmosphere. It is also sensitive to strain, with a maximum gauge factor of −6.0. As a proof of concept, we have used DIW-LS technology to fabricate a thin-film heat flux sensor on the surface of the turbine blade, capable of measuring heat flux densities over 1 MW/m2. This DIW-LS process provides a viable approach for the integrated, rapid, and flexible fabrication of thin film sensors for harsh environments. [ABSTRACT FROM AUTHOR]

The paper introduces an innovative methodology that combines photogrammetry and laser scanning techniques to create detailed 3D models of historic mansions within the Kifissia region of Attica, Greece. While photogrammetry excels in capturing intricate textures, it faces challenges such as lighting variations and precise image alignment. On the other hand, laser scanning offers precision in capturing geometric details but struggles with reflective surfaces and large datasets. Our study integrates these methods to leverage their strengths and address limitations, resulting in comprehensive and accurate digital twins of cultural spaces. The methodology section outlines the step-by-step process of integration, emphasizing solutions to specific challenges encountered in the study area. Preliminary results showcase the enhanced fidelity and completeness of the digital twins, demonstrating the effectiveness of the combined approach. The subsequent sections of the paper delve into a detailed presentation of the methodology, provide a comprehensive analysis of obtained results, and discuss the implications of this innovative approach in cultural preservation and broader applications. [ABSTRACT FROM AUTHOR]

This article relies on a combination of digital and analog data to analyze the 2D urban development of al-ʿAqaba and Jallūm districts in the Old City of Aleppo. The dataset consists of vectorized historical maps of the city spanning various historical periods. The oldest map in the collection dates back to the 1900s. Additionally, there are high-resolution orthomosaics created from a 3D model obtained through Terrestrial Laser Scanning (TLS) and Aerial Photogrammetry techniques. Through the analysis and integration of these various data types, the article proposes an analog-digital workflow that tracks the alterations in the urban fabric of the designated study area. The analysis primarily examines the alterations in the city's two-dimensional layout and the distribution of mass and void. Tracking the changes in the street network of the studied area is the main goal of this research, along with recognizing the spatial changes in the built environment. The article identified changes in both the open spaces and the street layout. [ABSTRACT FROM AUTHOR]

This paper explores how co-designing urban walkability can be augmented by an innovative hybrid approach, whereby virtual records and visualisations of the walking experience can enhance the awareness, perceptions and immersion of the participant in both real and virtual spaces. From one side of that model, the research explores how people might be intrigued enough to discover the real context, based on their experience informed and enriched by parallel images of the city. On the other side, the study aimed to develop a critical understanding of urban walking through the lens of 3D high-definition LIDAR scanning technology, where visualisation techniques were used to support studies to explore how the rich experience of walking could be captured and represented. The paper presents a theoretical framework to propose how walking could be promoted, and positively influenced by the urban environment, by regarding the city from the abstract perspective of the virtual point cloud. The research has investigated how and whether a place – real and abstracted – could act as a trigger to produce novel ideas and unfold thoughts in a participatory way. The interlinkages between motion and (visual) perception of the environment as an aesthetic experience were critical to informing how digital technology can be utilised as a virtual space within which the richness of real interactions and experiences with urban space can be represented, refined, interacted with and used within a rich(er) process of co-design. [ABSTRACT FROM AUTHOR]

The restoration of historic buildings and structures involves a wide range of scientific and technical fields. The grouting process is among an array of rehabilitation and preservation interventions and aims to homogenize the structure after the implementation of strengthening measures. The process can provide important information regarding the state of preservation of the examined structure and correlate the progress of the process with the pathology of the monument. To achieve this, the analysis of typical raw grouting data is progressively fused with additional information from the diagnostic studies, non-destructive testing, geospatial information, and from the calculation and analysis of grouting indices. The restoration project of the Katholikon of the Monastery of Panagia Varnakova in Fokida, Greece was selected as the case study, due to its large scale and the severe earthquake damage it has sustained, which has necessitated comprehensive strengthening interventions and extensive grouting. The implementation of an integrated methodological approach validated the enhanced level of co-analysis, revealing information that is not readily deduced from a typical approach. Selected sub-areas of the Katholikon are presented, demonstrating how the observed pathology can be correlated with the results of the grouting process, while incorporating 3D data, and findings from structural and non-destructive analyses. [ABSTRACT FROM AUTHOR]

This study aims to describe the numerical modeling and nonlinear finite element analysis of typical spinal braces as a first step towards optimizing their topology for 3D printing. Numerical simulation was carried out in Abaqus CAE software Version 2021, utilizing a CAD (Meshmixer Version 3.5.474) scan of an actual spinal brace. Boundary conditions were defined by means of contact surfaces between the human body and the supporting pads located in the interior of the brace. The process of tightening the straps on the rear face of the brace was simulated via appropriate imposed displacements. The response is described through the deformations and developing stresses of the brace and the contact pressures in the areas of interaction with the human body. Parametric analysis indicated that increasing the cross-sectional thickness or elastic modulus of the brace material results in higher maximum von Mises stresses and lower displacements. The comparison between 3D-printed and conventional braces highlighted the potential of 3D-printing technology to achieve comparable performance with customized designs, leveraging the constitutive properties of 3D-printed material obtained from tension tests. The tension tests demonstrated that the 3D-printed material achieved higher values of modulus of elasticity compared to traditional brace materials. Finally, the topology optimization criteria to be applied for the design of spinal braces in the next step of this ongoing research are briefly described. [ABSTRACT FROM AUTHOR]

Copyright of Architectonics & Architecture / Építés - Építészettudomány is the property of Akademiai Kiado and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the development of tunnel construction, the detection, control, and treatment of all kinds of tunnel lining diseases have received increased attention. Therefore, tunnel nondestructive testing technology is widely used as an intelligent emerging technology. Due to the cost limitations of industrial applications, nondestructive testing technology of medium- and small-shield tunnels experiences serious losses in accuracy and speed when transferred to large-diameter shield tunnels. A large shield tunnel forming quality inspection vehicle is developed by integrating a two-dimensional (2D) laser scanner with a wheel shaft encoder and an industrial computer. Based on this equipment, an asymmetric shield quality inspection method based on digital images is proposed. By analyzing the construction environment of a large-diameter shield tunnel, the ground and vehicle body point clouds are filtered, the central axis is extracted using the neighborhood vector method, and the central coordinate system of the tunnel is established. The inspection route is arranged eccentrically, and the sampling point clouds are divided into dense and sparse side point clouds according to their tunnel density. Moreover, different methods are used to pick up the joint features of the segment. The dense side point cloud is expanded around the central axis into a 2D gray image, and the joint image is segmented by scaling, normalization, and gradient threshold segmentation. According to the classification of joints based on the linear equation, the linear distribution formula of sparse and dense side joints is deduced by combining the segment structure and the point placement, with the sparse side joints picked up indirectly. According to the joint characteristic points, the edge point clusters on both sides of the segment and the segment misalignment are calculated. The least square method is used to fit the tunnel point cloud and calculate tunnel ellipticity. Tests are conducted in a large-diameter shield tunnel to verify the effectiveness of the inspection method, and the following conclusions are made from the test results: The inspection speed of the molding quality inspection vehicle in the 14-meter shield tunnel is 3 km·h−1; compared with traditional detection methods, the average deviation of segment dislocation detection is less than 2 mm; the average deviation of tunnel contour maximum deformation detection is less than 2 mm, and the average deviation of ovality detection is less than 0.1%. This meets the high-speed, high-precision, and low-cost requirements of large-diameter shield tunnel molding quality inspections.

This article relies on a combination of digital and analog data to analyze the 2D urban development of al-ʿAqaba and Jallūm districts in the Old City of Aleppo. The dataset consists of vectorized historical maps of the city spanning various historical periods. The oldest map in the collection dates back to the 1900s. Additionally, there are high-resolution orthomosaics created from a 3D model obtained through Terrestrial Laser Scanning (TLS) and Aerial Photogrammetry techniques. Through the analysis and integration of these various data types, the article proposes an analog-digital workflow that tracks the alterations in the urban fabric of the designated study area. The analysis primarily examines the alterations in the city’s two-dimensional layout and the distribution of mass and void. Tracking the changes in the street network of the studied area is the main goal of this research, along with recognizing the spatial changes in the built environment. The article identified changes in both the open spaces and the street layout.

Interference and collisions often occur in the loading process at shipyards. Existing simulation methods focus primarily on resource processes and schedules, and there is a lack of real-time reflection in the complex and highly variable loading process. This study aims to develop a spatial environment incorporating real-time product data, such as hulls, and confirms its effectiveness by simulating various construction scenarios. As a method, a near real-time spatial environment based on broadband laser scanning was established, with the situation of loading heavy cargo assumed when converting an existing ship into an LNG dual-fuel propulsion ship. A case study simulation of near-real-time cargo loading processes was then conducted using Unity 3D to confirm the interference and collision risks within the spatial environment. The results indicated that interference occurred in structures previously not identified in the design data, and a collision occurred during the loading object erection phase. The simulation confirmed that the identification of interference and collision risks during the erection phase highlights the need for a relocation or removal process of potential hazards before erection takes place. An improved erection simulation that integrates near real-time data could effectively prevent interference and collision risks.

ABSTRACT: Introduction. Existing automated construction inspection technologies do not allow the user to select the level of detail. At the same time, in the context of the use of nanotechnology, there is a growing need to expand the capabilities of monitoring and control of construction projects. The aim of the research is to develop, implement software, and validate a technology for controlling the speed and accuracy of constructing three-dimensional models from dense point clouds for automated monitoring of construction works. Materials and methods. The research is based on the methodology of non-binary data trees, including the method of constructing octant trees. An unmanned aerial vehicle with an aerial laser scanner, a ground-based scanning total station, and specialized software were used, including the web application “Management System for Monitoring Construction Works on Objects that have undergone state expertise” developed with the participation of the authors. Results and discussion. In the course of the study, a technology was developed and implemented in software that allows the user to select the required balance between accuracy, degree of detail of monitoring and control data for construction work and time costs and computing power requirements. The comparison is made between a construction project, presented in the form of a building information model, and a three-dimensional model of a real object, obtained from a dense point cloud. The degree of comparison accuracy is set by choosing the level of octrees used. By default, the web application uses level eight. However, in the early stages of construction, when the geometric parameters of a dense point cloud deviate significantly from the design boundaries, the ninth, tenth and other levels can be used. In this case, the accuracy and degree of detail increases. Positive and negative deviations are visualized in red and blue colors, respectively, which allows the user to monitor and control the progress of work at the site. Conclusions. The developed technology can be used by customers and other decision makers to control and monitor work.

Traditional measurement methods are still widely used for recording cultural heritage objects. On the other hand, geodetic surveying and modern technologies such as 3D laser scanning can provide more accurate, geometrically consistent and extremely detailed data that can be used as a basis for detailed vector maps or 3D models. The main aim of our research was to investigate the complementary approach, using both traditional and modern methods, in order to produce detailed vector maps of the Romanesque church of St. Martin in Chapaize, France, which are essential for further unveiling its historic development. Geometrically, this church is rather extensive and has many irregularities in its shape. Our approach to the documentation process is presented and evaluated in this paper. We applied the Procrustes analysis for the ground floor map, which gave us an objective accuracy assessment. Point clouds of the bell tower acquired by two different laser instruments have also been compared.

The significance of data acquisition in archaeological practice has consistently held great importance. Over the past few decades, the growing prevalence of digitization in acquiring data has significantly transformed the landscape of archaeological fieldwork, influencing both methodology and interpretation. The integration of digital photogrammetry and laser scanning technologies in archaeology has transformed data acquisition, enabling efficient and precise documentation. However, this digital shift raises concerns about information overload, the potential loss of on-site insights, and the need for suitable data management methods. Over the past 15 years, digital tools like photogrammetry, laser scanning, and unmanned aerial vehicles have advanced cultural heritage documentation. These methods offer detailed 3D models of archaeological sites, artifacts, and monuments, with evolving accessibility and user friendliness. This paper delves into methods for documenting cultural heritage, examining the implications of various approaches on the archaeologist’s workflow and on the field as a whole.

Uncrewed aerial vehicles (UAV) have great potential for use in forest inventories, but in practice they can be expensive for relatively small inventory areas as a large number of field measurements are needed for model construction. One proposed solution is to transfer previously constructed models to a new inventory area and to calibrate these with a small number of local field measurements. Our objective was to compare calibration of general models and the construction of new models to determine the best approach for UAV-based forest inventories. Our material included field measurements and UAV-based laser scanning data, from which individual trees were automatically identified. A general mixed-effects model for diameter at breast height (DBH) had been formulated earlier based on data from a geographically wider area. It was calibrated to the study area with field measurements from 2–10 randomly selected calibration trees. The calibrated diameters were used to calculate the diameter of a basal area median tree (DGM), tree volumes, and the volume of all trees at plot-level. Next, new DBH-models were formulated based on the 2–10 randomly selected trees and calibrated with plot-level random effects estimated during model construction. Finally, plot-specific height-diameter regression models were formulated by randomly selecting 10 trees from each plot. Calibration reduced the prediction errors of all variables. An increase in the number of calibration trees decreased error rates by 1–6% depending on the variable. Calibrated predictions from the general mixed-effects model were similar to the separately formulated mixed-effects models and plot-specific regression models.

The gas flow distribution inside a blast furnace affects its smelting. Laser surface detection technology can control the gas flow distribution and promote the stable and smooth running of blast furnace by observing and adjusting the surface condition in the blast furnace in real-time. The laser surface inspection technology in blast furnace gas flow control and optimization was introduced, with Masteel 4,000 m3 blast furnace as an example. The results showed that the 30 W high-power laser had good penetration performance and could obtain clear scanning images of the material surface. In the process of strengthening smelting, the laser detection system determined that the central airflow of blast furnace was insufficient, resulting in a decrease in furnace condition stability, and promptly took measures to adjust the angle of the mineral coke fabric equipment and lifting line. After adjusting the material line, the central airflow was properly suppressed and stabilized, the angle of edge platform increased, the airflow developed properly, and two suitable gas flows were formed, which finally stabilized the furnace condition. Meanwhile, the small duct airflow other than the central airflow was found in time through the laser detection system, which provided conditions for operators to take measures to effectively eliminate the duct airflow, thereby avoiding big impacts on the blast furnace operation and technical and economic indexes. Therefore, the laser surface detection technology could effectively judge the gas flow distribution in the furnace, which contributed to timely adjustment of process parameters and optimization of blast furnace operation.

In the studies on Prehistoric Graphic Expression, there are recurrent discussions about the tracings generated by different observers of the same motif. Methodological issues concerning the role of archaeological imaging are often implied within those debates. Do the tracings belong to the observational data exposition chapter, or are they part of the interpretative conclusions? How can the current technological scenario help solve these problems? In 2017, we conducted new documentation of the Peña Tu rock shelter, a well-known site with an intriguing post-palaeolithic graphic collection documented on several occasions throughout the twentieth century. Our objective was to provide quantifiable and, if possible, objective documentation of the painted and engraved remnants on the shelter’s surface. To achieve this, we employed two data capture strategies. One strategy focused on analysing the vestiges of paintings using a hyperspectral sensor, while the other centred on the geometric definition of engravings and the rock support, utilising photogrammetric techniques and laser scanning. These approaches presented various parallax challenges. Despite these challenges, our results were highly satisfactory. We resolved uncertainties regarding the formal features of specific designs that had been subject to debate for a long time. Additionally, we discovered previously unpublished areas with traces of paintings. Lastly, we developed a map highlighting recent alterations and deteriorations, providing a valuable tool for assessing the site’s preservation status. In conclusion, by employing advanced technology and comprehensive documentation methods, we significantly contributed to understanding and preserving the prehistoric graphic expressions at the Peña Tu rock shelter. [ABSTRACT FROM AUTHOR]

Understanding the contributions of stream bank and bed erosion will allow us to implement the most effective management practices. The objective of this study was to assess different methods to measure bank and bed erosion at different scales, specifically the watershed, reach and plot. Innovative and traditional methods were utilized. At the watershed scale, indices based on free satellite images were used. For the reach scale, indices were used, but the images with higher accuracy were purchased and captured by unmanned aerial vehicles (UAVs). At the plot scale, erosion pins, cross-sections and laser scanning were applied. The watershed scale analysis showcased "hot spots". These "hot spots" were reaches vulnerable to erosion and deposition. The indices of the purchased images were applied to these "hot spots" and allowed us to narrow the length of the reaches where UAV flights took place. These flight images located where erosion and deposition occurred. Finally, at the plot scale, laser scanning provided more detailed and accurate data at a greater scale compared to the traditional methods. The implementation of these methods allows us to find the areas vulnerable to erosion and deposition. These are the areas where nature-based solutions should be implemented to effectively mitigate erosion problems. [ABSTRACT FROM AUTHOR]

Copyright of Builder (1896-0642) is the property of PWB MEDIA Zdzieblowski sp.j. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Uneven road surfaces are the primary source of excitation in the dynamic interaction between a bridge and a vehicle and can lead to errors in bridge weigh-in-motion (B-WIM) systems. In order to correctly reproduce this interaction in a numerical model of a bridge, it is essential to know the magnitude and location of the various roadway irregularities. This paper presents a methodology for measuring the 3D road surface using static terrestrial laser scanning and a numerical model for simulating vehicle passage over a bridge with a measured road surface. This model allows the evaluation of strain responses in the time domain at any bridge location considering different parameters such as vehicle type, lateral position and speed, road surface unevenness, bridge type, etc. Since the time domain strains are crucial for B-WIM algorithms, the proposed approach facilitates the analysis of the different factors affecting the B-WIM results. The first validation of the proposed methodology was carried out on a real bridge, where extensive measurements were performed using different sensors, including measurements of the road surface, the response of the bridge when crossed by a test vehicle and the dynamic properties of the bridge and vehicle. The comparison between the simulated and measured bridge response marks a promising step towards investigating the influence of unevenness on the results of B-WIM. [ABSTRACT FROM AUTHOR]

• Methodology for a complete geometrical analysis of the vaults of Notre-Dame de Paris after the fire. • 2D image-based method for comparison before and after the fire. • 3D point cloud-based method for comparison before and after the fire. • New method for accurate alignment of very large point clouds. The work presented in this article was carried out following the fire (April 15, 2019) that ravaged Notre-Dame de Paris. The goal was to establish in a short and limited time-span the structural diagnosis of the remaining vaults of the cathedral. The analysis relied on 2D and 3D data acquired before and after the fire, and available at that time. Two complementary methods have been developed to estimate potential displacements from multi-temporal surveys. The first method is mainly based on the processing of image collections obtained with photogrammetric routines right after the fire. The second method, based on the processing of raw 3D data acquired with Terrestrial Laser Scanning, was developed afterward to refine and complete the analysis. Both methods have benefited from essential functionalities offered by two open-source solutions proven to enable "real-based" modeling in Cultural Heritage contexts, namely Micmac and CloudCompare. This paper presents the complementary use of these two software packages whilst detailing some procedural computing approaches to document and support structural diagnosis in an emergency situation. The limits and capabilities of each method are exposed and analyzed, toward the objective to develop 2.5D and 3D based geometrical analysis, respectively from photogrammetric and lasergrammetric sources. The results are presented and discussed regarding their potential usage for a quantitative and accurate diagnosis of vaults. [ABSTRACT FROM AUTHOR]

Landslides represent a significant natural hazard with wide-reaching impacts. Addressing the challenge of accurately detecting and monitoring landslides, this research introduces a novel approach that combines feature tracking with histogram analysis for efficient outlier removal. Distinct from existing methods, our approach leverages advanced histogram techniques to significantly enhance the accuracy of landslide detection, setting a new standard in the field. Furthermore, when tested on three different data sets, this method demonstrated a notable reduction in outliers by approximately 15 to 25 percent of all displacement vectors, exemplifying its effectiveness. Key to our methodology is a refined feature tracking process utilizing terrestrial laser scanners, renowned for their precision and detail in capturing surface information. This enhanced feature tracking method allows for more accurate and reliable landslide monitoring, representing a significant advancement in geospatial analysis techniques. [ABSTRACT FROM AUTHOR]

Simple Summary: Cranial cruciate ligament (CCL) insufficiency is a common condition in dogs, commonly treated using tibial plateau leveling osteotomy (TPLO). CCL injury often results in secondary abnormalities of the menisci. Arthrotomy is still used by many veterinarians to detect meniscal damage, and also, before TPLO an assessment of the menisci is generally recommended. However, only a limited part of the menisci is visible during arthrotomy of the stifle. Our hypothesis was that the change in tibial plateau position created by TPLO allows a better visual access to the menisci. To verify suspicion, we compared the degree of visibility of the lateral and medial menisci before and after TPLO on 15 identical 3-dimensional (3D)-printed models of a normal canine tibia. On each model, the meniscal area was stained and photographed, and its part visible to the surgeon before and after TPLO was digitally measured and compared. Our modeling showed that before TPLO, without additional instrumentation, e.g., arthroscopy, only approximately 16% of the entire meniscus area was visible. We demonstrated that TPLO increased the visibility of the lateral meniscus to 38–56% (mean ± SD: 46.5 ± 5.4%) of its entire area and of the medial meniscus to 41–70% (mean ± SD: 52.8 ± 7.6%). This increase in the visibility was statistically significant (p < 0.001). We conclude that performing the examination of the menisci after TPLO allows for a review of about 50% of the entire meniscal area, in contrast to examination before TPLO, where only about 16% is visible. The visible area is slightly smaller in the lateral than in the medial meniscus; however, this difference is unlikely to be clinically relevant. The aim of this study was to compare the degree of visibility of the lateral and medial menisci before and after tibial plateau leveling osteotomy (TPLO) on 3D-printed models created after laser scanning of the right tibia with menisci derived from a fresh cadaver of a 4-year-old adult male golden retriever. The models were produced of white polylactic acid, and the menisci were filled with light-curing red resin. The models showed a similar conformation as the natural specimen harvested from the cadaver, maintaining the same length and width, in addition to reproducing the anatomical structures. From the pre- and post-TPLO radiographs, it was possible to identify the anatomical structures corresponding to the tibial plateau. The preoperative tibial plateau angle was 26.2°, and the postoperative one ranged between 4.0° and 5.3° (4.6 ± 0.4°). In the bird's-eye photo, the total number of red pixels in the lateral and the medial meniscus was 2,053,995 and 2,140,939, respectively. Before TPLO, only between 14% and 19% of the entire area of the menisci was visible, and the unhidden part of the entire area of the meniscus before TPLO did not differ significantly between the lateral (16.2 ± 1.6%) and the medial (16.4 ± 1.6%) meniscus (p = 0.351). The visible part of the entire meniscus area increased significantly after TPLO both in the lateral and medial menisci (p < 0.001)—mean difference ± SD of 30.3 ± 4.3% (CI 95%: 27.9%, 32.6%) and 36.4 ± 6.4% (CI 95%: 32.9%, 40.0%), respectively. In conclusion, the intraoperative examination and treatment of dog menisci are easier after TPLO. [ABSTRACT FROM AUTHOR]

The process of excavating rock mass induces changes in the stress distribution within the slope, rendering it prone to deformation over a specific duration. The potential consequence of movements along the weak planes is the ultimate breakdown of the slope. Various monitoring techniques, including visual inspection, laser scanning, Lidar scanning, total stations, Global Positioning Systems (GPS), state-of-the-art radar scanning, and micro-seismic monitoring, are currently employed in mining environments to forecast slope failure and deformation rate. This article will discuss the need to implement a continuous slope monitoring system, including categorizing such systems and an overview of the current state of existing slope monitoring technologies. The paper also discusses the applications of UAVs (Unmanned Aerial Vehicles) in slope monitoring. The research proposes implementing a consistent and continuous slope monitoring strategy grounded on empirical data when planning big and deep opencast mines. This approach is crucial for guaranteeing optimal safety measures and enhanced productivity levels. [ABSTRACT FROM AUTHOR]

Robust and effective fruit detection and localization is essential for robotic harvesting systems. While extensive research efforts have been devoted to improving fruit detection, less emphasis has been placed on the fruit localization aspect, which is a crucial yet challenging task due to limited depth accuracy from existing sensor measurements in the natural orchard environment with variable lighting conditions and foliage/branch occlusions. In this paper, we present the system design and calibration of an Active LAser-Camera Scanner (ALACS), a novel perception module for robust and high-precision fruit localization. The hardware of the ALACS mainly consists of a red line laser, an RGB camera, and a linear motion slide, which are seamlessly integrated into an active scanning scheme where a dynamic-targeting laser-triangulation principle is employed. A high-fidelity extrinsic model is developed to pair the laser illumination and the RGB camera, enabling precise depth computation when the target is captured by both sensors. A random sample consensus-based robust calibration scheme is then designed to calibrate the model parameters based on collected data. Comprehensive evaluations are conducted to validate the system model and calibration scheme. The results show that the proposed calibration method can detect and remove data outliers to achieve robust parameter computation, and the calibrated ALACS system is able to achieve high-precision localization with the maximum depth measurement error being less than 4 mm at distance ranging from 0.6 to 1.2 m. [ABSTRACT FROM AUTHOR]

This research paper discusses the development of a spiral laser scanning photoacoustic microscopy (sLS-PAM) system for functional brain imaging in rats. The aim of the study was to create a high-resolution, fast frame-rate, and wide field-of-view (FOV) PAM system that can capture hemodynamic changes in the brain. The sLS-PAM system was able to image cerebral hemodynamics in response to whisker and electrical stimulation, as well as vascular imaging of a modeled brain injury. The researchers believe that this simple-to-implement PAM system could become an affordable functional neuroimaging tool for researchers. [Extracted from the article]

Copyright of Archives of Civil Engineering (Polish Academy of Sciences) is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Infrastructure asset management needs extensive data collection to create a comprehensive inventory record that consolidates pertinent asset details, encompassing their operational and maintenance activities in an integrated manner. Conventionally, the initial assessment involves a laborious, tedious, and expensive random walkthrough visual inspection. With the advancements in assets management as a result of ongoing digital transformation, it is believed that laser scanning can be a game changer in easing visual inspection and digital inventory development if deployed in the infrastructures' asset management. Using a case study of a station from the Bus Rapid Transit (BRT) Peshawar, this study explores the use of laser scanning as an alternative to manual inspection, employing Scan-to-BIM for asset management of infrastructures. The station's façade details at two different time intervals were laser-scanned to view the parametric details and geometrical features of its components and their physical condition in a virtual environment. Following validation of the scanned data through field inspection for accuracy and reliability, the data was utilized to develop semantic 3D models of the station with realistic geometries and dimensions. These models represent the as-is state of the assets covering the temporal geometrical changes in the form of added, deducted, or degraded elements as highlighted from the comparison of the successive models. Consequently, an intelligent and efficient 3D inventory and geometrical change detection system emerged, offering a viable substitute for traditional inventorying and data collection techniques. Thus, the study adds a new dimension to the application of laser scanning in asset management through its utilization for change detection and deformation tracking of the geometrical façades of the infrastructures in addition to the data acquisition for inventory development. [ABSTRACT FROM AUTHOR]

The paper presents the geometrical properties of those surfaces that can be digitized by 3D laser scanners. First the circumstances of the experiment are described. The device (Roland LPX-1200) and applied software (Dr. Pizza) are also introduced, such as the brief historical development of 3D digitization. Based on the data found in the literature, all those problems are collected, that can emerge during 3D laser scanning. In order to find the limits of the scanner, a test specimen was designed with a variety of geometric elements (planes in different positions, curved surfaces (concave, convex), roundings and chamfers in different sizes and positions, holes of different depths and diameter). During the design of the test specimen, those properties that were developed for additive technologies were used. The test specimen was produced by milling technology (Roland MDX 650), and then scanning with different settings were performed on it. The experiment was carried out until the largest real surface was digitized. Based on the test, it was summarized which geometries can be fully or partially scanned. Finally, a recommendation to achieve the best possible result was formulated. [ABSTRACT FROM AUTHOR]

The significance of data acquisition in archaeological practice has consistently held great importance. Over the past few decades, the growing prevalence of digitization in acquiring data has significantly transformed the landscape of archaeological fieldwork, influencing both methodology and interpretation. The integration of digital photogrammetry and laser scanning technologies in archaeology has transformed data acquisition, enabling efficient and precise documentation. However, this digital shift raises concerns about information overload, the potential loss of on-site insights, and the need for suitable data management methods. Over the past 15 years, digital tools like photogrammetry, laser scanning, and unmanned aerial vehicles have advanced cultural heritage documentation. These methods offer detailed 3D models of archaeological sites, artifacts, and monuments, with evolving accessibility and user friendliness. This paper delves into methods for documenting cultural heritage, examining the implications of various approaches on the archaeologist's workflow and on the field as a whole. [ABSTRACT FROM AUTHOR]

OPAs (On-chip optical phased arrays) are enabling method for a variety of applications, including metrology, LIDAR (light detection and ranging), and optical interconnects. OPAs must achieve a low beam width, wide-angle steering, effective sidelobe suppression, and other performance requirements. Presence of grating sidelobes from these array configurations in far-field pattern makes it difficult to guide a beam without aliasing when antenna element spacing is more than half a wavelength. Either 1D linear or 2D rectangular arrays make up majority of OPA configurations. This research proposes novel technique for analyzing the laser scanning by ion beam with photogrammetry mapping analysis and nanofabrication. The nanofabrication is carried out using carbon coated optical silicon insulator. The bandwidth restrictions of their antennas as well as photoconductor parasitic have limited the operation bandwidth of previously exhibited plasmonic photoconductive antennas. Here, we demonstrate a potent method for fabricating large-area plasmonic photoconductive nano-antenna arrays that can be used to create broadband terahertz detectors. Signal-to-noise ratio, beam steering step response, beam divergence, power consumption, and scalability are all included in the simulation analysis. [ABSTRACT FROM AUTHOR]

The emergence of new technologies has dynamized the way in which cultural heritage is documented, preserved, and passed on to new generations; something that determines a paradigm shift in terms of research in this field. Most operations now also have access to the virtual component. In this context, the current study aimed to make accessible through virtual and augmented reality one of the most interesting objectives belonging to the Jewish cultural heritage built in Art Nouveau style in the municipality of Oradea (Romania), which currently functions as a La Belle Epoque Museum. In the study, the techniques of terrestrial, aerial photogrammetry, and terrestrial laser scanning were used to remodel, in a three-dimensional format, as faithful as possible and usable in different applications, the special architecture of the exterior of the monument. This information was doubled by making the interior of the monument accessible through a complete and complex series of panoramic images interconnected within a virtual tour that will be made available to tourists interested in discovering the Darvas-La Roche House. The virtual tour, which includes both graphic, textual, and audio information, represents an innovative approach for the buildings built in Art Nouveau style in the municipality of Oradea, representing a virtual bridge for better promotion of the tourist destination and for the awareness of the local people regarding the importance of preserving and appreciating the local cultural heritage. This is all the more important as this is the first initiative to make the Art Nouveau buildings in Oradea Municipality accessible to the general public in an innovative way. [ABSTRACT FROM AUTHOR]

The issues of classification and characterization of surface operational defects according to the results of ultrasonic, eddy current, and visual inspection methods of nondestructive testing are considered. At the same time, the visual inspection method was realized with the use of a television inspection camera equipped with a computer vision function and a laser triangulation sensor. The paper presents a dataset containing 5760 images of pipelines with and without pitting corrosion. A convolutional neural network (CNN) is presented that was applied to classify the images obtained from the TV inspection camera into images without corrosion and images with pitting corrosion. The paper presents a dataset containing 269 measurements of planar and volumetric surface defects. A model for surface defect sizing based on gradient boosting is presented. The paper develops an algorithm for classification and sizing of surface defects in complex diagnostics in which the obtained models are applied, and determines the accuracy of this algorithm in the RMSE metric, which was calculated within the studied test dataset and amounted to 0.011 mm. [ABSTRACT FROM AUTHOR]

The authors propose a sequence of acquisition and interpretation of geospatial data obtained using different methods and means during mineral mining toward the accuracy increase in evaluation of industrially disturbed land. This approach uses the concept of stage-wise transition from the areas of industrial facilities to their individual points. The integration of data of satellite surveys, ground-based laser scanning and unmanned aerial surveillance in the digital models of land areas is described. It is highlighted that the rational combination of different methods of geospatial data acquisition and interpretation produces a high-accurate geoinformation system of digital twins of various subsoil use facilities. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Expresión Gráfica en la Edificación is the property of Universidad Politecnica de Valencia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Turkey Lidar Journal / Türkiye Lidar Dergisi is the property of Mersin University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Turkey Lidar Journal / Türkiye Lidar Dergisi is the property of Mersin University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recently, point cloud technology has been applied in the ship engineering field. However, the dense point cloud acquired by terrestrial laser scanning (TLS) technology in ship engineering applications brings an obstacle to some powerful and advanced point-based deep learning point cloud processing methods. This paper presents a deep learning pre-procession module to ensure the feasibility of processing dense point clouds on commonly available computer devices. The pre-procession module is designed according to the traditional point cloud processing methods and the PointNet++ paradigm, and is evaluated on two ship structure datasets and two popular point cloud datasets. Experimental results illustrate that (i) the proposed module improves the performance of point-based deep learning semantic segmentation networks, and (ii) the proposed module empowers the existing point-based deep learning networks with the capability to process dense input point clouds. The proposed module may provide a useful semantic segmentation tool for realistic dense point clouds in various industrial applications. [ABSTRACT FROM AUTHOR]

The article delves into the application of laser scanning within the realm of engineering, concentrating its examination on rotary kilns. Through an in-depth case study, this article meticulously assesses the advantages inherent in utilising laser scanning technology and draws comparisons with conventional measurement methods. The overarching objective of the investigation is to unravel the intricate relationship between the deterioration of the rotary kiln liners and the ovality of the underlying steel structure. By meticulously analysing these aspects, this article seeks to contribute valuable insights into the understanding of this complex interplay in the context of engineering practices. As a measurement apparatus, a terrestrial laser scanner was used. The interior and exterior of the rotary kiln were measured. The primary focus object was inner-lining loss and the geometric characteristics of the cylindrical shells. The research uncovered significant disparities in inner lining loss between the sections. A correlation was found between the ovality and elimination of the inner lining. Due to the hypothesis of constant inner lining loss in the middle of the rotary kiln, the investigation found that the loss of brick lining was less than the value reported from the wells. This study offers significant information on the maintenance and repair strategies for rotary kilns, which have the potential to increase their efficiency and useful life. [ABSTRACT FROM AUTHOR]

An abandoned gypsum mine has been discovered beneath the route of a highway construction in Hunan province, south China. Due to the highway construction and operations safety, there is an urgent need for a comprehensive stability analysis of the abandoned mining area. The 3D laser scanning detection technique has been adopted, and over 400 drillholes were strategically placed near the highway to capture the spatial information of the abandoned gypsum mine. The ore body has an average mining thickness of about 3 m, and the depth of the mining roof ranges from 40 to 60 m, with an average span of 16 m. Based on the research achievements in the engineering geological investigation, rock mass quality assessment, and geometry information, a simplified numerical model has been established for stability analysis. The numerical model employed the IMASS rock mass constitutive model to conduct a stability analysis of the abandoned gypsum mine during the excavation process and in the medium to long term. The IMASS constitutive model can effectively reflect the entire process of rock mass from microscopic damage to macroscopic instability, and the numerical simulation of current and long-term stages provides a much greater understanding of the mining room stability and the effect of various geo-mechanical parameters not considered in traditional empirical methods. The abandoned gypsum mine stability is guaranteed in the mining and current stages. However, the numerical results showed that a 0.4 m spalling thickness of the sidewalls can cause an overall instability and failure of the abandoned mine, and reinforcement measures must be taken for long-term safety. The stability of the abandoned gypsum mine with filling solutions was also evaluated numerically. [ABSTRACT FROM AUTHOR]