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10 pages, 192 KiB  
Article
The Word Made Flesh and the Spirit’s Breath: Bridging Christology and Pneumatology in Animal Theology
by Daniela Rizzo
Religions 2024, 15(11), 1355; https://doi.org/10.3390/rel15111355 - 7 Nov 2024
Viewed by 400
Abstract
This paper proposes a synthesis of Christological and pneumatological insights to present a more inclusive vision of creation’s role in divine worship and redemption. While deep incarnation emphasizes Christ’s identification with all of creation, this study extends the discussion by incorporating the Spirit’s [...] Read more.
This paper proposes a synthesis of Christological and pneumatological insights to present a more inclusive vision of creation’s role in divine worship and redemption. While deep incarnation emphasizes Christ’s identification with all of creation, this study extends the discussion by incorporating the Spirit’s ongoing work through the framework of animal glossolalia. Nonhuman creatures are seen not merely as passive recipients of Christ’s redemptive work but as active participants in cosmic worship through the Spirit’s intercession. By uniting the shared flesh of Christ with the Spirit’s transformative presence, the paper suggests a more integrated theological vision that includes all living beings in the divine narrative. This approach invites us to reconsider the role of animals within a broader ecological and theological framework, urging a reimagining of their spiritual capacities and their place in the eschatological hope for the renewal of all creation. Full article
(This article belongs to the Section Religions and Theologies)
14 pages, 223 KiB  
Article
Educational Poverty and Deprivation: Attitudes and the Role of Teachers during the Pandemic
by Maddalena Colombo, Diego Mesa, Gianluca Battilocchi and Gianluca Truscello
Societies 2024, 14(9), 190; https://doi.org/10.3390/soc14090190 - 21 Sep 2024
Viewed by 1089
Abstract
Educational poverty is widespread in compulsory education in terms of poor learning and socio-cultural disadvantages; it affects students with disabilities, students with learning difficulties, and those with an immigrant background. During the pandemic crisis, students with special educational needs (SENs) mostly suffered the [...] Read more.
Educational poverty is widespread in compulsory education in terms of poor learning and socio-cultural disadvantages; it affects students with disabilities, students with learning difficulties, and those with an immigrant background. During the pandemic crisis, students with special educational needs (SENs) mostly suffered the risk of an additional deprivation. Within an advanced inclusive model during school closure, the Italian State guaranteed access to schools only to students with disabilities. What effects did this “equalizing” measure produce? What kinds of attitudes have teachers adopted and what roles have they played (active vs. passive) in order to make it sustainable? What was their acknowledgement of the educational poverty and deprivation? To what extent were their attitudes differentiated? This article explores the roles and attitudes of teachers during periods of lockdown as a result of the COVID-19 pandemic in Italy. We assume that the teachers’ attitudes were differentiated on the basis of five cultural dimensions (auto/hetero-referencing; vision of remote teaching; relationship with bureaucracy, relationships with students; teaching as performance or relation), and two functions (classroom teachers/ SENs teachers). The study is based on 42 semi-structured interviews conducted with teachers, principals, and parents in six lower secondary public schools with high rates of SENs students and multi-ethnicity (Northern Italy), and focused on the organisational, teaching, and relational aspects. Results seem to confirm that not all teachers agreed with the Ministry line and adopted a range of responses to the challenge of maintaining inclusivity, from the inert/impatient to the creative/active ones. Their attitudes changed during the post-pandemic period from atomistic to more collaborative, and their preoccupation with the fragile “uncertified students” increased. The article closes with recommendations on teacher training. Full article
(This article belongs to the Topic Diversity Competence and Social Inequalities)
18 pages, 4531 KiB  
Article
Does Forest Contemplation Provide Greater Psychological Benefits than Passive Exposure to the Urban Forest? A Pilot Study
by Emilia Janeczko, Małgorzata Woźnicka, Katarzyna Śmietańska, Anna Wiśniewska, Natalia Korcz and Agata Kobyłka
Forests 2024, 15(8), 1411; https://doi.org/10.3390/f15081411 - 12 Aug 2024
Cited by 1 | Viewed by 802
Abstract
Human contact with the natural environment effectively counteracts negative symptoms of stress and has many positive psychological effects. For this reason, forests within city limits are increasingly seen as part of public health promotion. Being in an urban forest can take many forms, [...] Read more.
Human contact with the natural environment effectively counteracts negative symptoms of stress and has many positive psychological effects. For this reason, forests within city limits are increasingly seen as part of public health promotion. Being in an urban forest can take many forms, but there is still little known about whether being in a forest alone, without engaging one’s senses, is as effective for human renewal as an experience that involves greater, more conscious activation of the senses of sight, hearing, smell. A study measuring the effect of the forest (spring aspect) on human mental relaxation during passive exposure was conducted on a sample of 19 Polish young adults. The experiment consisted of two series. In the first, participants read an academic textbook in a tree stand for 20 min, while in the next session—conducted at the same location—they contemplated the landscape. Before the experiment and after each of the two series of tests, four psychological questionnaires were administered: the Profile of Mood State (POMS), Positive and Negative Affect Schedule (PANAS), the Restorative Outcome Scale (ROS) and the Subjective Vitality Scale (SVS). Analyses showed that being in a forest environment positively influenced the subjects’ mental relaxation, while the level of benefit from the activation of the senses, especially vision (looking at the forest) was significantly higher compared to the passive activity of reading a text. The research indicates that forest bathing is the best form of relaxation that can be obtained through contact with the forest. Full article
(This article belongs to the Section Forest Economics, Policy, and Social Science)
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14 pages, 6477 KiB  
Article
Passive Vision Detection of Torch Pose in Swing Arc Narrow Gap Welding
by Na Su, Haojin Jia, Liyu Chen, Jiayou Wang, Jie Wang and Youmin Song
Sensors 2024, 24(15), 4996; https://doi.org/10.3390/s24154996 - 2 Aug 2024
Viewed by 628
Abstract
To enhance the synchronous detection of the horizontal and vertical positions of the torch in swing arc narrow gap welding, a torch pose detection (TPD) method is proposed. This approach utilizes passive visual sensing to capture images of the arc on the groove [...] Read more.
To enhance the synchronous detection of the horizontal and vertical positions of the torch in swing arc narrow gap welding, a torch pose detection (TPD) method is proposed. This approach utilizes passive visual sensing to capture images of the arc on the groove sidewall, using advanced image processing methods to extract and fit the arc contour. The coordinates of the arc contour center point and the highest point are determined through the arc contour fitting line. The torch center position is calculated from the average horizontal coordinates of the arc contour centers in adjacent welding images, while the height position is determined from the vertical coordinate of the arc’s highest point. Experimental validation in both variable and constant groove welding conditions demonstrated the TPD method’s accuracy within 0.32 mm for detecting the torch center position. This method eliminates the need to construct the wire centerline, which was a requirement in previous approaches, thereby reducing the impact of wire straightness on detection accuracy. The proposed TPD method successfully achieves simultaneous detection of the torch center and height positions, laying the foundation for intelligent detection and adaptive control in swing arc narrow gap welding. Full article
(This article belongs to the Section Electronic Sensors)
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16 pages, 3317 KiB  
Article
Optimizing Strawberry Disease and Quality Detection with Vision Transformers and Attention-Based Convolutional Neural Networks
by Kimia Aghamohammadesmaeilketabforoosh, Soodeh Nikan, Giorgio Antonini and Joshua M. Pearce
Foods 2024, 13(12), 1869; https://doi.org/10.3390/foods13121869 - 14 Jun 2024
Viewed by 1381
Abstract
Machine learning and computer vision have proven to be valuable tools for farmers to streamline their resource utilization to lead to more sustainable and efficient agricultural production. These techniques have been applied to strawberry cultivation in the past with limited success. To build [...] Read more.
Machine learning and computer vision have proven to be valuable tools for farmers to streamline their resource utilization to lead to more sustainable and efficient agricultural production. These techniques have been applied to strawberry cultivation in the past with limited success. To build on this past work, in this study, two separate sets of strawberry images, along with their associated diseases, were collected and subjected to resizing and augmentation. Subsequently, a combined dataset consisting of nine classes was utilized to fine-tune three distinct pretrained models: vision transformer (ViT), MobileNetV2, and ResNet18. To address the imbalanced class distribution in the dataset, each class was assigned weights to ensure nearly equal impact during the training process. To enhance the outcomes, new images were generated by removing backgrounds, reducing noise, and flipping them. The performances of ViT, MobileNetV2, and ResNet18 were compared after being selected. Customization specific to the task was applied to all three algorithms, and their performances were assessed. Throughout this experiment, none of the layers were frozen, ensuring all layers remained active during training. Attention heads were incorporated into the first five and last five layers of MobileNetV2 and ResNet18, while the architecture of ViT was modified. The results indicated accuracy factors of 98.4%, 98.1%, and 97.9% for ViT, MobileNetV2, and ResNet18, respectively. Despite the data being imbalanced, the precision, which indicates the proportion of correctly identified positive instances among all predicted positive instances, approached nearly 99% with the ViT. MobileNetV2 and ResNet18 demonstrated similar results. Overall, the analysis revealed that the vision transformer model exhibited superior performance in strawberry ripeness and disease classification. The inclusion of attention heads in the early layers of ResNet18 and MobileNet18, along with the inherent attention mechanism in ViT, improved the accuracy of image identification. These findings offer the potential for farmers to enhance strawberry cultivation through passive camera monitoring alone, promoting the health and well-being of the population. Full article
(This article belongs to the Section Plant Foods)
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18 pages, 1121 KiB  
Review
Metabolic Regulation of Endothelial Cells: A New Era for Treating Wet Age-Related Macular Degeneration
by Xirui Chen, Yang Xu, Yahan Ju and Ping Gu
Int. J. Mol. Sci. 2024, 25(11), 5926; https://doi.org/10.3390/ijms25115926 - 29 May 2024
Viewed by 1140
Abstract
Wet age-related macular degeneration (wet AMD) is a primary contributor to visual impairment and severe vision loss globally, but the prevailing treatments are often unsatisfactory. The development of conventional treatment strategies has largely been based on the understanding that the angiogenic switch of [...] Read more.
Wet age-related macular degeneration (wet AMD) is a primary contributor to visual impairment and severe vision loss globally, but the prevailing treatments are often unsatisfactory. The development of conventional treatment strategies has largely been based on the understanding that the angiogenic switch of endothelial cells (ECs) is mainly dictated by angiogenic growth factors. Even though treatments targeting vascular endothelial growth factor (VEGF), like ranibizumab, are widely administered, more than half of patients still exhibit inadequate or null responses, suggesting the involvement of other pathogenic mechanisms. With advances in research in recent years, it has become well recognized that EC metabolic regulation plays an active rather than merely passive responsive role in angiogenesis. Disturbances of these metabolic pathways may lead to excessive neovascularization in angiogenic diseases such as wet AMD, therefore targeted modulation of EC metabolism represents a promising therapeutic strategy for wet AMD. In this review, we comprehensively discuss the potential applications of EC metabolic regulation in wet AMD treatment from multiple perspectives, including the involvement of ECs in wet AMD pathogenesis, the major endothelial metabolic pathways, and novel therapeutic approaches targeting metabolism for wet AMD. Full article
(This article belongs to the Special Issue Advances on Retinal Diseases: 2nd Edition)
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21 pages, 2424 KiB  
Article
Shape Sensing and Kinematic Control of a Cable-Driven Continuum Robot Based on Stretchable Capacitive Sensors
by Wenjun Shen, Jianhui He, Guilin Yang, Xiangjie Kong, Haotian Bai and Zaojun Fang
Sensors 2024, 24(11), 3385; https://doi.org/10.3390/s24113385 - 24 May 2024
Viewed by 1026
Abstract
A Cable-Driven Continuum Robot (CDCR) that consists of a set of identical Cable-Driven Continuum Joint Modules (CDCJMs) is proposed in this paper. The CDCJMs merely produce 2-DOF bending motions by controlling driving cable lengths. In each CDCJM, a pattern-based flexible backbone is employed [...] Read more.
A Cable-Driven Continuum Robot (CDCR) that consists of a set of identical Cable-Driven Continuum Joint Modules (CDCJMs) is proposed in this paper. The CDCJMs merely produce 2-DOF bending motions by controlling driving cable lengths. In each CDCJM, a pattern-based flexible backbone is employed as a passive compliant joint to generate 2-DOF bending deflections, which can be characterized by two joint variables, i.e., the bending direction angle and the bending angle. However, as the bending deflection is determined by not only the lengths of the driving cables but also the gravity and payload, it will be inaccurate to compute the two joint variables with its kinematic model. In this work, two stretchable capacitive sensors are employed to measure the bending shape of the flexible backbone so as to accurately determine the two joint variables. Compared with FBG-based and vision-based shape-sensing methods, the proposed method with stretchable capacitive sensors has the advantages of high sensitivity to the bending deflection of the backbone, ease of implementation, and cost effectiveness. The initial location of a stretchable sensor is generally defined by its two endpoint positions on the surface of the backbone without bending. A generic shape-sensing model, i.e., the relationship between the sensor reading and the two joint variables, is formulated based on the 2-DOF bending deflection of the backbone. To further improve the accuracy of the shape-sensing model, a calibration method is proposed to compensate for the location errors of stretchable sensors. Based on the calibrated shape-sensing model, a sliding-mode-based closed-loop control method is implemented for the CDCR. In order to verify the effectiveness of the proposed closed-loop control method, the trajectory tracking accuracy experiments of the CDCR are conducted based on a circle trajectory, in which the radius of the circle is 55mm. The average tracking errors of the CDCR measured by the Qualisys motion capture system under the open-loop and the closed-loop control are 49.23 and 8.40mm, respectively, which is reduced by 82.94%. Full article
(This article belongs to the Special Issue Robust Motion Recognition Based on Sensor Technology)
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46 pages, 50054 KiB  
Review
Passive Polarized Vision for Autonomous Vehicles: A Review
by Julien R. Serres, Pierre-Jean Lapray, Stéphane Viollet, Thomas Kronland-Martinet, Antoine Moutenet, Olivier Morel and Laurent Bigué
Sensors 2024, 24(11), 3312; https://doi.org/10.3390/s24113312 - 22 May 2024
Viewed by 1592
Abstract
This review article aims to address common research questions in passive polarized vision for robotics. What kind of polarization sensing can we embed into robots? Can we find our geolocation and true north heading by detecting light scattering from the sky as animals [...] Read more.
This review article aims to address common research questions in passive polarized vision for robotics. What kind of polarization sensing can we embed into robots? Can we find our geolocation and true north heading by detecting light scattering from the sky as animals do? How should polarization images be related to the physical properties of reflecting surfaces in the context of scene understanding? This review article is divided into three main sections to address these questions, as well as to assist roboticists in identifying future directions in passive polarized vision for robotics. After an introduction, three key interconnected areas will be covered in the following sections: embedded polarization imaging; polarized vision for robotics navigation; and polarized vision for scene understanding. We will then discuss how polarized vision, a type of vision commonly used in the animal kingdom, should be implemented in robotics; this type of vision has not yet been exploited in robotics service. Passive polarized vision could be a supplemental perceptive modality of localization techniques to complement and reinforce more conventional ones. Full article
(This article belongs to the Section Sensors and Robotics)
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36 pages, 7878 KiB  
Review
Advances in Real-Time 3D Reconstruction for Medical Endoscopy
by Alexander Richter, Till Steinmann, Jean-Claude Rosenthal and Stefan J. Rupitsch
J. Imaging 2024, 10(5), 120; https://doi.org/10.3390/jimaging10050120 - 14 May 2024
Viewed by 2540
Abstract
This contribution is intended to provide researchers with a comprehensive overview of the current state-of-the-art concerning real-time 3D reconstruction methods suitable for medical endoscopy. Over the past decade, there have been various technological advancements in computational power and an increased research effort in [...] Read more.
This contribution is intended to provide researchers with a comprehensive overview of the current state-of-the-art concerning real-time 3D reconstruction methods suitable for medical endoscopy. Over the past decade, there have been various technological advancements in computational power and an increased research effort in many computer vision fields such as autonomous driving, robotics, and unmanned aerial vehicles. Some of these advancements can also be adapted to the field of medical endoscopy while coping with challenges such as featureless surfaces, varying lighting conditions, and deformable structures. To provide a comprehensive overview, a logical division of monocular, binocular, trinocular, and multiocular methods is performed and also active and passive methods are distinguished. Within these categories, we consider both flexible and non-flexible endoscopes to cover the state-of-the-art as fully as possible. The relevant error metrics to compare the publications presented here are discussed, and the choice of when to choose a GPU rather than an FPGA for camera-based 3D reconstruction is debated. We elaborate on the good practice of using datasets and provide a direct comparison of the presented work. It is important to note that in addition to medical publications, publications evaluated on the KITTI and Middlebury datasets are also considered to include related methods that may be suited for medical 3D reconstruction. Full article
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23 pages, 12189 KiB  
Article
Automated Lane Centering: An Off-the-Shelf Computer Vision Product vs. Infrastructure-Based Chip-Enabled Raised Pavement Markers
by Parth Kadav, Sachin Sharma, Johan Fanas Rojas, Pritesh Patil, Chieh (Ross) Wang, Ali Riza Ekti, Richard T. Meyer and Zachary D. Asher
Sensors 2024, 24(7), 2327; https://doi.org/10.3390/s24072327 - 5 Apr 2024
Viewed by 1839
Abstract
Safe autonomous vehicle (AV) operations depend on an accurate perception of the driving environment, which necessitates the use of a variety of sensors. Computational algorithms must then process all of this sensor data, which typically results in a high on-vehicle computational load. For [...] Read more.
Safe autonomous vehicle (AV) operations depend on an accurate perception of the driving environment, which necessitates the use of a variety of sensors. Computational algorithms must then process all of this sensor data, which typically results in a high on-vehicle computational load. For example, existing lane markings are designed for human drivers, can fade over time, and can be contradictory in construction zones, which require specialized sensing and computational processing in an AV. But, this standard process can be avoided if the lane information is simply transmitted directly to the AV. High definition maps and road side units (RSUs) can be used for direct data transmission to the AV, but can be prohibitively expensive to establish and maintain. Additionally, to ensure robust and safe AV operations, more redundancy is beneficial. A cost-effective and passive solution is essential to address this need effectively. In this research, we propose a new infrastructure information source (IIS), chip-enabled raised pavement markers (CERPMs), which provide environmental data to the AV while also decreasing the AV compute load and the associated increase in vehicle energy use. CERPMs are installed in place of traditional ubiquitous raised pavement markers along road lane lines to transmit geospatial information along with the speed limit using long range wide area network (LoRaWAN) protocol directly to nearby vehicles. This information is then compared to the Mobileye commercial off-the-shelf traditional system that uses computer vision processing of lane markings. Our perception subsystem processes the raw data from both CEPRMs and Mobileye to generate a viable path required for a lane centering (LC) application. To evaluate the detection performance of both systems, we consider three test routes with varying conditions. Our results show that the Mobileye system failed to detect lane markings when the road curvature exceeded ±0.016 m−1. For the steep curvature test scenario, it could only detect lane markings on both sides of the road for just 6.7% of the given test route. On the other hand, the CERPMs transmit the programmed geospatial information to the perception subsystem on the vehicle to generate a reference trajectory required for vehicle control. The CERPMs successfully generated the reference trajectory for vehicle control in all test scenarios. Moreover, the CERPMs can be detected up to 340 m from the vehicle’s position. Our overall conclusion is that CERPM technology is viable and that it has the potential to address the operational robustness and energy efficiency concerns plaguing the current generation of AVs. Full article
(This article belongs to the Special Issue Advanced Sensing Technology for Intelligent Transportation Systems)
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12 pages, 1917 KiB  
Review
Aquaporins in the Cornea
by Samuel Melnyk and Wendy B. Bollag
Int. J. Mol. Sci. 2024, 25(7), 3748; https://doi.org/10.3390/ijms25073748 - 28 Mar 2024
Viewed by 1194
Abstract
The cornea is an avascular, transparent tissue that allows light to enter the visual system. Accurate vision requires proper maintenance of the cornea’s integrity and structure. Due to its exposure to the external environment, the cornea is prone to injury and must undergo [...] Read more.
The cornea is an avascular, transparent tissue that allows light to enter the visual system. Accurate vision requires proper maintenance of the cornea’s integrity and structure. Due to its exposure to the external environment, the cornea is prone to injury and must undergo proper wound healing to restore vision. Aquaporins (AQPs) are a family of water channels important for passive water transport and, in some family members, the transport of other small molecules; AQPs are expressed in all layers of the cornea. Although their functions as water channels are well established, the direct function of AQPs in the cornea is still being determined and is the focus of this review. AQPs, primarily AQP1, AQP3, and AQP5, have been found to play an important role in maintaining water homeostasis, the corneal structure in relation to proper hydration, and stress responses, as well as wound healing in all layers of the cornea. Due to their many functions in the cornea, the identification of drug targets that modulate the expression of AQPs in the cornea could be beneficial to promote corneal wound healing and restore proper function of this tissue crucial for vision. Full article
(This article belongs to the Special Issue Recent Advances in Aquaporins)
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22 pages, 275 KiB  
Article
Insights into Shared Decision-Making in Interprofessional Teams for a Boy with Down Syndrome with Communication and Language Issues: Simulation-Based Training for Medical and Allied Health Students
by Stijn R. J. M. Deckers and Yvonne van Zaalen
Healthcare 2024, 12(6), 681; https://doi.org/10.3390/healthcare12060681 - 18 Mar 2024
Viewed by 2048
Abstract
Background: Shared decision-making is one key element of interprofessional collaboration. Communication is often considered to be the main reason for inefficient or ineffective collaboration. Little is known about group dynamics in the process of shared decision-making in a team with professionals, including the [...] Read more.
Background: Shared decision-making is one key element of interprofessional collaboration. Communication is often considered to be the main reason for inefficient or ineffective collaboration. Little is known about group dynamics in the process of shared decision-making in a team with professionals, including the patient or their parent. This study aimed to evaluate just that. Methods: Simulation-based training was provided for groups of medical and allied health profession students from universities across the globe. In an overt ethnographic research design, passive observations were made to ensure careful observations and accurate reporting. The training offered the context to directly experience the behaviors and interactions of a group of people. Results: Overall, 39 different goals were defined in different orders of prioritizing and with different time frames or intervention ideas. Shared decision-making was lacking, and groups chose to convince the parents when a conflict arose. Group dynamics made parents verbally agree with professionals, although their non-verbal communication was not in congruence with that. Conclusions: The outcome and goalsetting of an interprofessional meeting are highly influenced by group dynamics. The vision, structure, process, and results of the meeting are affected by multiple inter- or intrapersonal factors. Full article
38 pages, 53898 KiB  
Review
Large-Scale 3D Reconstruction from Multi-View Imagery: A Comprehensive Review
by Haitao Luo, Jinming Zhang, Xiongfei Liu, Lili Zhang and Junyi Liu
Remote Sens. 2024, 16(5), 773; https://doi.org/10.3390/rs16050773 - 22 Feb 2024
Cited by 2 | Viewed by 5861
Abstract
Three-dimensional reconstruction is a key technology employed to represent virtual reality in the real world, which is valuable in computer vision. Large-scale 3D models have broad application prospects in the fields of smart cities, navigation, virtual tourism, disaster warning, and search-and-rescue missions. Unfortunately, [...] Read more.
Three-dimensional reconstruction is a key technology employed to represent virtual reality in the real world, which is valuable in computer vision. Large-scale 3D models have broad application prospects in the fields of smart cities, navigation, virtual tourism, disaster warning, and search-and-rescue missions. Unfortunately, most image-based studies currently prioritize the speed and accuracy of 3D reconstruction in indoor scenes. While there are some studies that address large-scale scenes, there has been a lack of systematic comprehensive efforts to bring together the advancements made in the field of 3D reconstruction in large-scale scenes. Hence, this paper presents a comprehensive overview of a 3D reconstruction technique that utilizes multi-view imagery from large-scale scenes. In this article, a comprehensive summary and analysis of vision-based 3D reconstruction technology for large-scale scenes are presented. The 3D reconstruction algorithms are extensively categorized into traditional and learning-based methods. Furthermore, these methods can be categorized based on whether the sensor actively illuminates objects with light sources, resulting in two categories: active and passive methods. Two active methods, namely, structured light and laser scanning, are briefly introduced. The focus then shifts to structure from motion (SfM), stereo matching, and multi-view stereo (MVS), encompassing both traditional and learning-based approaches. Additionally, a novel approach of neural-radiance-field-based 3D reconstruction is introduced. The workflow and improvements in large-scale scenes are elaborated upon. Subsequently, some well-known datasets and evaluation metrics for various 3D reconstruction tasks are introduced. Lastly, a summary of the challenges encountered in the application of 3D reconstruction technology in large-scale outdoor scenes is provided, along with predictions for future trends in development. Full article
(This article belongs to the Section Urban Remote Sensing)
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24 pages, 2941 KiB  
Article
The Impact of Postures and Moving Directions in Fire Evacuation in a Low-Visibility Environment
by Jingjing Yan, Gengen He, Anahid Basiri, Craig Hancock and Siegfried K. Yeboah
Sensors 2024, 24(5), 1378; https://doi.org/10.3390/s24051378 - 21 Feb 2024
Viewed by 1270
Abstract
Walking speed is a significant aspect of evacuation efficiency, and this speed varies during fire emergencies due to individual physical abilities. However, in evacuations, it is not always possible to keep an upright posture, hence atypical postures, such as stoop walking or crawling, [...] Read more.
Walking speed is a significant aspect of evacuation efficiency, and this speed varies during fire emergencies due to individual physical abilities. However, in evacuations, it is not always possible to keep an upright posture, hence atypical postures, such as stoop walking or crawling, may be required for survival. In this study, a novel 3D passive vision-aided inertial system (3D PVINS) for indoor positioning was used to track the movement of 20 volunteers during an evacuation in a low visibility environment. Participants’ walking speeds using trunk flexion, trunk–knee flexion, and upright postures were measured. The investigations were carried out under emergency and non-emergency scenarios in vertical and horizontal directions, respectively. Results show that different moving directions led to a roughly 43.90% speed reduction, while posture accounted for over 17%. Gender, one of the key categories in evacuation models, accounted for less than 10% of the differences in speed. The speeds of participants under emergency scenarios when compared to non-emergency scenarios was also found to increase by 53.92–60% when moving in the horizontal direction, and by about 48.28–50% when moving in the vertical direction and descending downstairs. Our results also support the social force theory of the warming-up period, as well as the effect of panic on the facilitating occupants’ moving speed. Full article
(This article belongs to the Section Physical Sensors)
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15 pages, 7258 KiB  
Article
Active Object Detection and Tracking Using Gimbal Mechanisms for Autonomous Drone Applications
by Jakob Grimm Hansen and Rui Pimentel de Figueiredo
Drones 2024, 8(2), 55; https://doi.org/10.3390/drones8020055 - 6 Feb 2024
Cited by 2 | Viewed by 3923
Abstract
Object recognition, localization, and tracking play a role of primordial importance in computer vision applications. However, it is still an extremely difficult task, particularly in scenarios where objects are attended to using fast-moving UAVs that need to robustly operate in real time. Typically [...] Read more.
Object recognition, localization, and tracking play a role of primordial importance in computer vision applications. However, it is still an extremely difficult task, particularly in scenarios where objects are attended to using fast-moving UAVs that need to robustly operate in real time. Typically the performance of these vision-based systems is affected by motion blur and geometric distortions, to name but two issues. Gimbal systems are thus essential to compensate for motion blur and ensure visual streams are stable. In this work, we investigate the advantages of active tracking approaches using a three-degrees-of-freedom (DoF) gimbal system mounted on UAVs. A method that utilizes joint movement and visual information for actively tracking spherical and planar objects in real time is proposed. Tracking methodologies are tested and evaluated in two different realistic Gazebo simulation environments: the first on 3D positional tracking (sphere) and the second on tracking of 6D poses (planar fiducial markers). We show that active object tracking is advantageous for UAV applications, first, by reducing motion blur, caused by fast camera motion and vibrations, and, second, by fixating the object of interest within the center of the field of view and thus reducing re-projection errors due to peripheral distortion. The results demonstrate significant object pose estimation accuracy improvements of active approaches when compared with traditional passive ones. More specifically, a set of experiments suggests that active gimbal tracking can increase the spatial estimation accuracy of known-size moving objects, under conditions of challenging motion patterns and in the presence of image distortion. Full article
(This article belongs to the Section Drone Design and Development)
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