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Search Results (394)

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Keywords = road visibility

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20 pages, 14619 KiB  
Article
A Cognition–Affect–Behavior Framework for Assessing Street Space Quality in Historic Cultural Districts and Its Impact on Tourist Experience
by Dongsheng Huang, Weitao Gong, Xinyang Wang, Siyuan Liu, Jiaxin Zhang and Yunqin Li
Buildings 2025, 15(15), 2739; https://doi.org/10.3390/buildings15152739 - 3 Aug 2025
Abstract
Existing research predominantly focuses on the preservation or renewal models of the physical forms of historic cultural districts, with limited exploration of their roles in stimulating tourists’ cognitive, affective resonance, and behavioral interactions. This study addresses historic cultural districts by evaluating the space [...] Read more.
Existing research predominantly focuses on the preservation or renewal models of the physical forms of historic cultural districts, with limited exploration of their roles in stimulating tourists’ cognitive, affective resonance, and behavioral interactions. This study addresses historic cultural districts by evaluating the space quality and its impact on tourist experiences through the “cognition-affect-behavior” framework, integrating GIS, street view semantic segmentation, VR eye-tracking, and web crawling technologies. The findings reveal significant multidimensional differences in how space quality influences tourist experiences: the impact intensities of functional diversity, sky visibility, road network accessibility, green visibility, interface openness, and public facility convenience decrease sequentially, with path coefficients of 0.261, 0.206, 0.205, 0.204, 0.201, and 0.155, respectively. Additionally, space quality exerts an indirect effect on tourist experiences through the mediating roles of cognitive, affective, and behavioral dimensions, with a path coefficient of 0.143. This research provides theoretical support and practical insights for empowering cultural heritage space governance with digital technologies in the context of cultural and tourism integration. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
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32 pages, 10052 KiB  
Article
A Study on Large Electric Vehicle Fires in a Tunnel: Use of a Fire Dynamics Simulator (FDS)
by Roberto Dessì, Daniel Fruhwirt and Davide Papurello
Processes 2025, 13(8), 2435; https://doi.org/10.3390/pr13082435 - 31 Jul 2025
Viewed by 267
Abstract
Internal combustion engine vehicles damage the environment and public health by emitting toxic fumes, such as CO2 or CO and other trace compounds. The use of electric cars helps to reduce the emission of pollutants into the environment due to the use [...] Read more.
Internal combustion engine vehicles damage the environment and public health by emitting toxic fumes, such as CO2 or CO and other trace compounds. The use of electric cars helps to reduce the emission of pollutants into the environment due to the use of batteries with no direct and local emissions. However, accidents of battery electric vehicles pose new challenges, such as thermal runaway. Such accidents can be serious and, in some cases, may result in uncontrolled overheating that causes the battery pack to spontaneously ignite. In particular, the most dangerous vehicles are heavy goods vehicles (HGVs), as they release a large amount of energy that generate high temperatures, poor visibility, and respiratory damage. This study aims to determine the potential consequences of large BEV fires in road tunnels using computational fluid dynamics (CFD). Furthermore, a comparison between a BEV and an ICEV fire shows the differences related to the thermal and the toxic impact. Furthermore, the adoption of a longitudinal ventilation system in the tunnel helped to mitigate the BEV fire risk, keeping a safer environment for tunnel users and rescue services through adequate smoke control. Full article
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13 pages, 1881 KiB  
Article
Transforming Rice Husk Ash into Road Safety: A Sustainable Approach to Glass Microsphere Production
by Ingrid Machado Teixeira, Juliano Pase Neto, Acsiel Budny, Luis Enrique Gomez Armas, Chiara Valsecchi and Jacson Weber de Menezes
Ceramics 2025, 8(3), 93; https://doi.org/10.3390/ceramics8030093 - 24 Jul 2025
Viewed by 274
Abstract
Glass microspheres are essential components in horizontal road markings due to their retroreflective properties, enhancing visibility and safety under low-light conditions. Traditionally produced from soda-lime glass made with high-purity silica from sand, their manufacturing raises environmental concerns amid growing global sand scarcity. This [...] Read more.
Glass microspheres are essential components in horizontal road markings due to their retroreflective properties, enhancing visibility and safety under low-light conditions. Traditionally produced from soda-lime glass made with high-purity silica from sand, their manufacturing raises environmental concerns amid growing global sand scarcity. This study explores the viability of rice husk ash (RHA)—a high-silica byproduct of rice processing—as a sustainable raw material for microsphere fabrication. A glass composition containing 70 wt% SiO2 was formulated using RHA and melted at 1500 °C. Microspheres were produced through flame spheroidization and characterized following the Brazilian standard NBR 16184:2021 for Type IB beads. The RHA-derived microspheres exhibited high sphericity, appropriate size distribution (63–300 μm), density of 2.42 g/cm3, and the required acid resistance. UV-Vis analysis confirmed their optical transparency, and the refractive index was measured as 1.55 ± 0.03. Retroreflectivity tests under standardized conditions revealed performance comparable to commercial counterparts. These results demonstrate the technical feasibility of replacing conventional silica with RHA in glass microsphere production, aligning with circular economy principles and promoting sustainable infrastructure. Given Brazil’s significant rice production and corresponding RHA availability, this approach offers both environmental and socio-economic benefits for road safety and material innovation. Full article
(This article belongs to the Special Issue Ceramics in the Circular Economy for a Sustainable World)
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8 pages, 1746 KiB  
Proceeding Paper
Application of a Three-Dimensional Model in the Analysis of a Traffic Accident Involving a Motorcycle and a Pedestrian
by Milena Savova-Mratsenkova and Borislav Vasilovski
Eng. Proc. 2025, 100(1), 51; https://doi.org/10.3390/engproc2025100051 - 21 Jul 2025
Viewed by 131
Abstract
In this research work, the authors propose an approach for analyzing a traffic accident involving a motorcycle and a pedestrian. The study was conducted under the condition that there are objects in the accident area that limit the visibility of the participants. For [...] Read more.
In this research work, the authors propose an approach for analyzing a traffic accident involving a motorcycle and a pedestrian. The study was conducted under the condition that there are objects in the accident area that limit the visibility of the participants. For this purpose, a three-dimensional simulation model was developed to determine the relative positions of the pedestrian and the motorcycle-driver system at discrete moments, examining the period of time from the moment the pedestrian steps onto the roadway to the moment of contact between the participants. Data from a real traffic accident were used. Full article
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30 pages, 2282 KiB  
Article
User Experience of Navigating Work Zones with Automated Vehicles: Insights from YouTube on Challenges and Strengths
by Melika Ansarinejad, Kian Ansarinejad, Pan Lu and Ying Huang
Smart Cities 2025, 8(4), 120; https://doi.org/10.3390/smartcities8040120 - 19 Jul 2025
Viewed by 406
Abstract
Understanding automated vehicle (AV) behavior in complex road environments and user attitudes in such contexts is critical for their safe and effective integration into smart cities. Despite growing deployment, limited public data exist on AV performance in construction zones; highly dynamic settings marked [...] Read more.
Understanding automated vehicle (AV) behavior in complex road environments and user attitudes in such contexts is critical for their safe and effective integration into smart cities. Despite growing deployment, limited public data exist on AV performance in construction zones; highly dynamic settings marked by irregular lane markings, shifting detours, and unpredictable human presence. This study investigates AV behavior in these conditions through qualitative, video-based analysis of user-documented experiences on YouTube, focusing on Tesla’s supervised Full Self-Driving (FSD) and Waymo systems. Spoken narration, captions, and subtitles were examined to evaluate AV perception, decision-making, control, and interaction with humans. Findings reveal that while AVs excel in structured tasks such as obstacle detection, lane tracking, and cautious speed control, they face challenges in interpreting temporary infrastructure, responding to unpredictable human actions, and navigating low-visibility environments. These limitations not only impact performance but also influence user trust and acceptance. The study underscores the need for continued technological refinement, improved infrastructure design, and user-informed deployment strategies. By addressing current shortcomings, this research offers critical insights into AV readiness for real-world conditions and contributes to safer, more adaptive urban mobility systems. Full article
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17 pages, 36560 KiB  
Article
Comparative Calculation of Spectral Indices for Post-Fire Changes Using UAV Visible/Thermal Infrared and JL1 Imagery in Jinyun Mountain, Chongqing, China
by Juncheng Zhu, Yijun Liu, Xiaocui Liang and Falin Liu
Forests 2025, 16(7), 1147; https://doi.org/10.3390/f16071147 - 11 Jul 2025
Viewed by 215
Abstract
This study used Jilin-1 satellite data and unmanned aerial vehicle (UAV)-collected visible-thermal infrared imagery to calculate twelve spectral indices and evaluate their effectiveness in distinguishing post-fire forest areas and identifying human-altered land-cover changes in Jinyun Mountain, Chongqing. The research goals included mapping wildfire [...] Read more.
This study used Jilin-1 satellite data and unmanned aerial vehicle (UAV)-collected visible-thermal infrared imagery to calculate twelve spectral indices and evaluate their effectiveness in distinguishing post-fire forest areas and identifying human-altered land-cover changes in Jinyun Mountain, Chongqing. The research goals included mapping wildfire impacts with M-statistic separability, measuring land-cover distinguishability through Jeffries–Matusita (JM) distance analysis, classifying land-cover types using the random forest (RF) algorithm, and verifying classification accuracy. Cumulative human disturbances—such as land clearing, replanting, and road construction—significantly blocked the natural recovery of burn scars, and during long-term human-assisted recovery periods over one year, the Red Green Blue Index (RGBI), Green Leaf Index (GLI), and Excess Green Index (EXG) showed high classification accuracy for six land-cover types: road, bare soil, deadwood, bamboo, broadleaf, and grass. Key accuracy measures showed producer accuracy (PA) > 0.8, user accuracy (UA) > 0.8, overall accuracy (OA) > 90%, and a kappa coefficient > 0.85. Validation results confirmed that visible-spectrum indices are good at distinguishing photosynthetic vegetation, thermal bands help identify artificial surfaces, and combined thermal-visible indices solve spectral confusion in deadwood recognition. Spectral indices provide high-precision quantitative evidence for monitoring post-fire land-cover changes, especially under human intervention, thus offering important data support for time-based modeling of post-fire forest recovery and improvement of ecological restoration plans. Full article
(This article belongs to the Special Issue Wildfire Behavior and the Effects of Climate Change in Forests)
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23 pages, 9575 KiB  
Article
Infrared and Visible Image Fusion via Residual Interactive Transformer and Cross-Attention Fusion
by Liquan Zhao, Chen Ke, Yanfei Jia, Cong Xu and Zhijun Teng
Sensors 2025, 25(14), 4307; https://doi.org/10.3390/s25144307 - 10 Jul 2025
Viewed by 350
Abstract
Infrared and visible image fusion combines infrared and visible images of the same scene to produce a more informative and comprehensive fused image. Existing deep learning-based fusion methods fail to establish dependencies between global and local information during feature extraction. This results in [...] Read more.
Infrared and visible image fusion combines infrared and visible images of the same scene to produce a more informative and comprehensive fused image. Existing deep learning-based fusion methods fail to establish dependencies between global and local information during feature extraction. This results in unclear scene texture details and low contrast of the infrared thermal targets in the fused image. This paper proposes an infrared and visible image fusion network to address this issue via the use of a residual interactive transformer and cross-attention fusion. The network first introduces a residual dense module to extract shallow features from the input infrared and visible images. Next, the residual interactive transformer extracts global and local features from the source images and establishes interactions between them. Two identical residual interactive transformers are used for further feature extraction. A cross-attention fusion module is also designed to fuse the infrared and visible feature maps extracted by the residual interactive transformer. Finally, an image reconstruction network generates the fused image. The proposed method is evaluated on the RoadScene, TNO, and M3FD datasets. The experimental results show that the fused images produced by the proposed method contain more visible texture details and infrared thermal information. Compared to nine other methods, the proposed approach achieves superior fusion performance. Full article
(This article belongs to the Section Sensing and Imaging)
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20 pages, 2004 KiB  
Review
An Overview of Intelligent Transportation Systems in Europe
by Nicolae Cordoș, Irina Duma, Dan Moldovanu, Adrian Todoruț and István Barabás
World Electr. Veh. J. 2025, 16(7), 387; https://doi.org/10.3390/wevj16070387 - 9 Jul 2025
Viewed by 627
Abstract
This paper provides a comprehensive review of the development, deployment and challenges of Intelligent Transport Systems (ITSs) in Europe. Driven by the EU Directive 2010/40/EU, the deployment of ITSs has become essential for improving the safety, efficiency and sustainability of transport. The study [...] Read more.
This paper provides a comprehensive review of the development, deployment and challenges of Intelligent Transport Systems (ITSs) in Europe. Driven by the EU Directive 2010/40/EU, the deployment of ITSs has become essential for improving the safety, efficiency and sustainability of transport. The study examines how ITS technologies, such as automation, real-time traffic data analytics and vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, have been integrated to improve urban mobility and road safety. In addition, it reviews significant European initiatives and case studies from several cities, which show visible improvements in reducing congestion, reducing CO2 emissions and increasing the use of public transport. The paper highlights, despite progress, major obstacles to widespread adoption, such as technical interoperability, inadequate regulatory frameworks and insufficient data sharing between stakeholders. These issues prevent ITS applications from scaling up and functioning well in EU Member States. To overcome these problems, the study highlights the need for common standards and cooperation frameworks. The research analyses the laws, technological developments and socio-economic effects of ITSs. By promoting sustainable and inclusive mobility, ITSs can contribute to the European Green Deal and climate goals. Finally, the paper presents ITSs as a revolutionary solution for future European transport systems and offers suggestions to improve their interoperability, data governance and policy support. Full article
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25 pages, 2747 KiB  
Article
Comparative Evaluation of Fuzzy Logic and Q-Learning for Adaptive Urban Traffic Signal Control
by Ioana-Miruna Vlasceanu, Vasilica-Cerasela-Doinita Ceapa, Ioan Stefan Sacala, Constantin Florin Caruntu, Andreea-Ioana Udrea, Nicolae Constantin and Mircea Segarceanu
Electronics 2025, 14(14), 2759; https://doi.org/10.3390/electronics14142759 - 9 Jul 2025
Viewed by 258
Abstract
In recent years, the number of vehicles in cities has visibly increased, leading to continuous modifications in general mobility. Pollution levels and congestion cases are reaching higher numbers as well, pointing to a need for better optimization solutions. Several existing control systems still [...] Read more.
In recent years, the number of vehicles in cities has visibly increased, leading to continuous modifications in general mobility. Pollution levels and congestion cases are reaching higher numbers as well, pointing to a need for better optimization solutions. Several existing control systems still rely on fixed timings for traffic lights, lacking an adaptive approach that can adjust the timers depending on real-time conditions. This study aims to provide a design for such a tool, by implementing two different approaches: Fuzzy Logic Optimization and an Adaptive Traffic Management strategy. The first controller involves Fuzzy Logic based on rule-based that adjust green and red-light timings depending on the number of vehicles at an intersection. The second model provides traffic adjustments based on external equipment such as road sensors and cameras, offering dynamic solutions tailored to current traffic conditions. Both methods are tested in a simulated environment using SUMO (Simulation of Urban Mobility). They were evaluated according to key efficiency indicators, namely average waiting time, lost time per cycle, number of stops per intersection, and overall traffic fluidity. Results demonstrate that Q-learning maintains consistent waiting times between 2.57 and 3.71 s across all traffic densities while achieving Traffic Flow Index values above 85%, significantly outperforming Fuzzy Logic, which shows greater variability and lower efficiency under high-density conditions. Full article
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19 pages, 1034 KiB  
Article
Assessing Tractors’ Active Safety in Serbia: A Driving Simulator Study
by Sreten Simović, Aleksandar Trifunović, Tijana Ivanišević, Vaidas Lukoševičius and Larysa Neduzha
Sustainability 2025, 17(13), 6144; https://doi.org/10.3390/su17136144 - 4 Jul 2025
Viewed by 366
Abstract
The active safety of tractors remains a major concern in rural road environments, where tractor drivers face high crash risks due to limited vehicle visibility. In Serbia, 1.4% of crashes involve tractors, mainly due to poor visibility (64.3%), lack of beacon lights, unsafe [...] Read more.
The active safety of tractors remains a major concern in rural road environments, where tractor drivers face high crash risks due to limited vehicle visibility. In Serbia, 1.4% of crashes involve tractors, mainly due to poor visibility (64.3%), lack of beacon lights, unsafe overtaking, and unmarked stopped tractors (14.3% each). These issues reduce safety, increase fuel consumption and emissions, and cause economic losses. A driving simulator study with 117 drivers examined how visibility equipment affects speed perception. The results showed that 20 km/h was best estimated with all visibility aids, while 10 km/h was most accurately judged with only the slow-moving vehicle emblem. These findings emphasize the potential for simple, cost-effective visibility measures to enhance the active safety of tractors in mixed rural traffic conditions. By enhancing tractor visibility, these measures reduce crash risks, minimize unnecessary acceleration and deceleration, and lower fuel consumption and emissions associated with traffic disturbances. Furthermore, by preventing crashes, these solutions contribute to reducing resource consumption in crash-related medical care, vehicle repairs, and infrastructure damage. Integrating improved visibility equipment into rural traffic policy can significantly enhance tractors’ active safety and reduce the risk of crashes in agricultural regions. Full article
(This article belongs to the Special Issue Transportation and Infrastructure for Sustainability)
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17 pages, 7477 KiB  
Article
The Development of a Lane Identification and Assessment Framework for Maintenance Using AI Technology
by Hohyuk Na, Do Gyeong Kim, Ji Min Kang and Chungwon Lee
Appl. Sci. 2025, 15(13), 7410; https://doi.org/10.3390/app15137410 - 1 Jul 2025
Viewed by 392
Abstract
This study proposes a vision-based framework to support AVs in maintaining stable lane-keeping by assessing the condition of lane markings. Unlike existing infrastructure standards focused on human visibility, this study addresses the need for criteria suited to sensor-based AV environments. Using real driving [...] Read more.
This study proposes a vision-based framework to support AVs in maintaining stable lane-keeping by assessing the condition of lane markings. Unlike existing infrastructure standards focused on human visibility, this study addresses the need for criteria suited to sensor-based AV environments. Using real driving data from urban expressways in Seoul, a YOLOv5-based lane detection algorithm was developed and enhanced through multi-label annotation and data augmentation. The model achieved a mean average precision (mAP) of 97.4% and demonstrated strong generalization on external datasets such as KITTI and TuSimple. For lane condition assessment, a pixel occupancy–based method was applied, combined with Canny edge detection and morphological operations. A threshold of 80-pixel occupancy was used to classify lanes as intact or worn. The proposed framework reliably detected lane degradation under various road and lighting conditions. These results suggest that quantitative, image-based indicators can complement traditional standards and guide AV-oriented infrastructure policy. Limitations include a lack of adverse weather data and dataset-specific threshold sensitivity. Full article
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26 pages, 3294 KiB  
Article
RIS-Aided V2I–VLC for the Next-Generation Intelligent Transportation Systems in Mountain Areas
by Wei Yang, Haoran Liu, Guangpeng Cheng, Zike Su and Yuanyuan Fan
Photonics 2025, 12(7), 664; https://doi.org/10.3390/photonics12070664 - 1 Jul 2025
Viewed by 338
Abstract
Visible light communication (VLC) is considered to be one of the key technologies for advancing the next-generation intelligent transportation systems (ITSs). However, in vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) VLC, the line-of-sight (LOS) link for communication is often obstructed by vehicle mobility. To address [...] Read more.
Visible light communication (VLC) is considered to be one of the key technologies for advancing the next-generation intelligent transportation systems (ITSs). However, in vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) VLC, the line-of-sight (LOS) link for communication is often obstructed by vehicle mobility. To address this issue and enhance system performance, a novel V2I–VLC system is proposed and analyzed in this study. The system targets mountain road traffic scenarios employing optical reflecting intelligent surfaces (RISs). To emphasize the practicality of the study, the effects of atmospheric turbulence (AT) and weather conditions are also considered in the channel modeling. Further, the closed-form expressions for average path loss, channel capacity, and outage probability are derived. Furthermore, a novel closed-form expression is also derived for the properties of RIS, which can be used to calculate the required number of RIS elements to achieve a target energy efficiency. In the performance analysis, the accuracy of the derived theoretical expression is validated by numerical simulation, and the effectiveness of the RIS-aided V2I–VLC system is evaluated. Moreover, with a reasonable number of required RIS elements, the system performance in terms of path loss is improved by more than 23.5% on average over the existing studies. Full article
(This article belongs to the Special Issue Emerging Technologies in Visible Light Communication)
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29 pages, 4413 KiB  
Article
Advancing Road Infrastructure Safety with the Remotely Piloted Safety Cone
by Francisco Javier García-Corbeira, David Alvarez-Moyano, Pedro Arias Sánchez and Joaquin Martinez-Sanchez
Infrastructures 2025, 10(7), 160; https://doi.org/10.3390/infrastructures10070160 - 27 Jun 2025
Viewed by 449
Abstract
This article presents the design, implementation, and validation of a Remotely Piloted Safety Cone (RPSC), an autonomous robotic system developed to enhance safety and operational efficiency in road maintenance. The RPSC addresses challenges associated with road works, including workers’ exposure to traffic hazards [...] Read more.
This article presents the design, implementation, and validation of a Remotely Piloted Safety Cone (RPSC), an autonomous robotic system developed to enhance safety and operational efficiency in road maintenance. The RPSC addresses challenges associated with road works, including workers’ exposure to traffic hazards and inefficiencies of traditional traffic cones, such as manual placement and retrieval, limited visibility in low-light conditions, and inability to adapt to dynamic changes in work zones. In contrast, the RPSC offers autonomous mobility, advanced visual signalling, and real-time communication capabilities, significantly improving safety and operational flexibility during maintenance tasks. The RPSC integrates sensor fusion, combining Global Navigation Satellite System (GNSS) with Real-Time Kinematic (RTK) for precise positioning, Inertial Measurement Unit (IMU) and encoders for accurate odometry, and obstacle detection sensors within an optimised navigation framework using Robot Operating System (ROS2) and Micro Air Vehicle Link (MAVLink) protocols. Complying with European regulations, the RPSC ensures structural integrity, visibility, stability, and regulatory compliance. Safety features include emergency stop capabilities, visual alarms, autonomous safety routines, and edge computing for rapid responsiveness. Field tests validated positioning accuracy below 30 cm, route deviations under 15 cm, and obstacle detection up to 4 m, significantly improved by Kalman filtering, aligning with digitalisation, sustainability, and occupational risk prevention objectives. Full article
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25 pages, 5088 KiB  
Article
Improved Perceptual Quality of Traffic Signs and Lights for the Teleoperation of Autonomous Vehicle Remote Driving via Multi-Category Region of Interest Video Compression
by Itai Dror and Ofer Hadar
Entropy 2025, 27(7), 674; https://doi.org/10.3390/e27070674 - 24 Jun 2025
Viewed by 719
Abstract
Autonomous vehicles are a promising solution to traffic congestion, air pollution, accidents, wasted time, and resources. However, remote driver intervention may be necessary in extreme situations to ensure safe roadside parking or complete remote takeover. In these cases, high-quality real-time video streaming is [...] Read more.
Autonomous vehicles are a promising solution to traffic congestion, air pollution, accidents, wasted time, and resources. However, remote driver intervention may be necessary in extreme situations to ensure safe roadside parking or complete remote takeover. In these cases, high-quality real-time video streaming is crucial for remote driving. In a preliminary study, we presented a region of interest (ROI) High-Efficiency Video Coding (HEVC) method where the image was segmented into two categories: ROI and background. This involved allocating more bandwidth to the ROI, which yielded an improvement in the visibility of classes essential for driving while transmitting the background at a lower quality. However, migrating the bandwidth to the large ROI portion of the image did not substantially improve the quality of traffic signs and lights. This study proposes a method that categorizes ROIs into three tiers: background, weak ROI, and strong ROI. To evaluate this approach, we utilized a photo-realistic driving scenario database created with the Cognata self-driving car simulation platform. We used semantic segmentation to categorize the compression quality of a Coding Tree Unit (CTU) according to its pixel classes. A background CTU contains only sky, trees, vegetation, or building classes. Essentials for remote driving include classes such as pedestrians, road marks, and cars. Difficult-to-recognize classes, such as traffic signs (especially textual ones) and traffic lights, are categorized as a strong ROI. We applied thresholds to determine whether the number of pixels in a CTU of a particular category was sufficient to classify it as a strong or weak ROI and then allocated bandwidth accordingly. Our results demonstrate that this multi-category ROI compression method significantly enhances the perceptual quality of traffic signs (especially textual ones) and traffic lights by up to 5.5 dB compared to a simpler two-category (background/foreground) partition. This improvement in critical areas is achieved by reducing the fidelity of less critical background elements, while the visual quality of other essential driving-related classes (weak ROI) is at least maintained. Full article
(This article belongs to the Special Issue Information Theory and Coding for Image/Video Processing)
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25 pages, 21149 KiB  
Article
Enhancing Conventional Land Surveying for Cadastral Documentation in Romania with UAV Photogrammetry and SLAM
by Lucian O. Dragomir, Cosmin Alin Popescu, Mihai V. Herbei, George Popescu, Roxana Claudia Herbei, Tudor Salagean, Simion Bruma, Catalin Sabou and Paul Sestras
Remote Sens. 2025, 17(13), 2113; https://doi.org/10.3390/rs17132113 - 20 Jun 2025
Cited by 1 | Viewed by 723
Abstract
This study presents an integrated surveying methodology for efficient and accurate cadastral documentation, combining UAV photogrammetry, SLAM-based terrestrial and aerial scanning, and conventional geodetic measurements. Designed to be scalable across various cadastral and planning contexts, the workflow was tested in Charlottenburg, Romania’s only [...] Read more.
This study presents an integrated surveying methodology for efficient and accurate cadastral documentation, combining UAV photogrammetry, SLAM-based terrestrial and aerial scanning, and conventional geodetic measurements. Designed to be scalable across various cadastral and planning contexts, the workflow was tested in Charlottenburg, Romania’s only circular heritage village. The approach addresses challenges in built environments where traditional total station or GNSS techniques face limitations due to obstructed visibility and complex architectural geometries. The SLAM system was initially deployed in mobile scanning mode using a backpack configuration for ground-level data acquisition, and was later mounted on a UAV to capture building sides and areas inaccessible from the main road. The results demonstrate that the integration of aerial and terrestrial data acquisition enables precise building footprint extraction, with a reported RMSE of 0.109 m between the extracted contours and ground-truth total station measurements. The final cadastral outputs are fully compatible with GIS and CAD systems, supporting efficient land registration, urban planning, and historical site documentation. The findings highlight the method’s applicability for modernizing cadastral workflows, particularly in dense or irregularly structured areas, offering a practical, accurate, and time-saving solution adaptable to both national and international land administration needs. Beyond the combination of known technologies, the innovation lies in the practical integration of terrestrial and aerial SLAM (dual SLAM) with RTK UAV workflows under real-world constraints, offering a field-validated solution for complex cadastral scenarios where traditional methods are limited. Full article
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