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•Real-world adversarial patch using 3D modeling techniques.•Using a 3D digital replica of the target scene to improve the patch’s performance.•An evaluation process that enables ...reproducible experiments in the real world.•Real-world adversarial patches that are robust to unexpected changes in the scene.
Adversarial examples have proven to be a concerning threat to deep learning models, particularly in the image domain. While many studies have examined adversarial examples in the real world, most of them relied on 2D photos of the attack scene. As a result, the attacks proposed may have limited effectiveness when implemented in realistic environments with 3D objects or varied conditions. Some studies on adversarial learning have used 3D objects, however in many cases, other researchers are unable to replicate the real-world evaluation process. In this study, we present a framework that uses 3D modeling to craft adversarial patches for an existing real-world scene. Our approach uses a 3D digital approximation of the scene to simulate the real world. With the ability to add and manipulate any element in the digital scene, our framework enables the attacker to improve the adversarial patch’s impact in real-world settings. We use the framework to create a patch for an everyday scene and evaluate its performance using a novel evaluation process that ensures that our results are reproducible in both the digital space and the real world. Our evaluation results show that the framework can generate adversarial patches that are robust to different settings in the real world.
Background:
Topical sinus irrigation plays a critical role in the management of sinonasal diseases. Yet, the penetration of irrigant to targeted sinuses may be highly variable and difficult to ...predict. Here, we investigate the use of 3D printing as a planning tool to optimize outcomes.
Methods:
Eight post-operative models were 3D printed with a FormLabs Form3 printer based on individual CT scans. Irrigations were performed and video recorded with a squeeze bottle attached via silicon water-tight seal, in 4 head positions: 45° to-the-side, 90° to-the-side, 45° forward and 45° to-the-side, and 90° forward, with irrigation fluid entering the upper (conventional) or lower (backfill) nostrils.
Results:
Significant individual variations were observed in sinus penetration as a function of head position. In general, the maxillary sinus was the easiest to irrigate in most head positions (P < .05), followed by frontal and ethmoid, with sphenoid being the most difficult. Both the 90°-to-the-side and the 90°-forward positions were significantly more effective than the others (P < .05), with 90°-forward better for frontal sinuses and 90°-to-the-side superior for all other sinuses. The backfill was significantly superior to conventional technique in head positions involving a side tilt (P < .05).
Conclusion:
Variations in technique and position significantly impacted irrigation outcome. Backfill irrigation that pushes fluid against gravity to pool around the ostium, seems to provide overall better outcomes. This study demonstrates the advantage of 3D printing as a rapid planning tool to guide irrigation strategies.
Abstract
The modeling and analysis of superconducting coils is an essential task in the design stage of most devices based on high-temperature superconductors (HTS). These calculations allow ...verifying basic estimations and assumptions, proposing improvements, and computing quantities that are not easy to calculate with an analytical approach. For instance, the estimation of losses in HTS is fundamental during the design stage since losses can strongly influence the cooling system requirements and operating temperature. Typically, 2D finite element analysis is used to calculate AC losses in HTS, due to the lack of analytical solutions that can accurately represent complex operating conditions, such as AC transport current and AC external applied magnetic field in coils. These 2D models are usually a representation of an infinitely long arrangement. Therefore, they cannot be used to analyze end effects and complex 3D configurations. In this publication, we use the homogenization of the T-A formulation in 3D for the analysis of superconducting coils with complex geometries where a 2D approach cannot provide accurate analyses and verification of assumptions. The modeling methodology allows an easier implementation in commercial software (COMSOL Multiphysics) in comparison with the currently available 3D H homogenization, despite the complexity of the geometry. This methodology is first validated with a racetrack coil (benchmark case) by comparing the results with the well-established H formulation. Then, the electromagnetic behavior of coils with more complex geometries is analyzed.
•Makerspaces are open-access workshops devoted to creative and technical work.•Digital scanners allow capturing reality and transforming it into a 3D digital file.•The 3D printers allow the creation ...of objects through the addition of diverse material.•Students value positively the Makerspace-environment towards the development of creativity.
Engineers need creativity to achieve different solutions to the same problem. Creative competence has become a cross competence in engineering studies. In this research an educational activity with 44 engineering students from La Laguna University is designed for stimulating creative competence. The emergence of new teaching-learning environments, in which digital fabrication techniques are used to turn ideas into digital designs, and these into tangible products through 3D printing offer an opportunity for the development of creativity. The Abreaction Test of Creativity is used to measure the creativity value at the beginning and the end of the experiment, and a survey is conducted to know the students’ perception of the influence in the development of their creativity. The results show that activities with digital editing tools and three-dimensional printing are valid for the development of creative competence: participants who performed the activity improved their creativity ability in 24,04 points. The perception of students about the impact of these activities on their creativity is high, with values above 3.5 out of 5.
The community structure and ecological function of marine ecosystems are critically dependent on phytoplankton. However, our understanding of phytoplankton is limited due to the lack of detailed ...information on their morphology. To address this gap, we developed a framework that combines scanning electron microscopy (SEM) with photogrammetry to create realistic 3D (three-dimensional) models of phytoplankton. The workflow of this framework is demonstrated using two marine algal species, one dinoflagellate Prorocentrum micans and one diatom Halamphora sp. The resulting 3D models are made openly available and allow users to interact with phytoplankton and their complex structures virtually (digitally) and tangibly (3D printing). They also allow for surface area and biovolume calculations of phytoplankton, as well as the exploration of their light scattering properties, which are both important for ecosystem modeling. Additionally, by presenting these models to the public, it bridges the gap between scientific inquiry and education, promoting broader awareness on the importance of phytoplankton.
In recent years, the rapid development of 3D printing technologies lead to its new applications in the area of healthcare and medicine, including dentistry, orthopedics, cardiovascular, ...pharmaceutics, neurosurgery, engineered tissue models, medical devices, and anatomical models. Dentistry is widely acknowledged to benefit from 3D printing technologies due to its needs for the customization and personalization of dental products. In this review, the authors discuss and summarize various 3D imaging technologies and the recent advances of 3D digital processing techniques in dentistry in an effort to give a new perspective and greater understanding of the current development of 3D printing technologies in dentistry. It is anticipated that this review will explore why 3D printing is important to dentistry, and why dentistry motivates development in 3D printing applications. Further, current challenges and further perspectives are also discussed which helps researchers to optimize the 3D printing technology in dentistry, improve 3D printing strategies, and direct future dental bioprinting and translational applications.
This article provides a comprehensive review of the recent development of 3D printing and 3D imaging technologies, and presents the recent advances of 3D printing in dentistry. Meanwhile, current challenges and further perspectives are also discussed which will benefit researchers to optimize the 3D printing technologies and strategies in dentistry, directing the future trend of the dental development.
The city digital twin is anticipated to accurately reflect and affect the city’s functions and processes to enhance its realization, operability, and management. Although research on the city digital ...twin is still in its infancy, the advancement of the digital twin technology is growing fast and providing viable contributions to augmenting smart city developments. This study reviews the literature to identify the current and prospective potentials and challenges of digital twin cities. A research agenda is also proposed to guide future research on the city digital twincity digital twin to reach the utmost level of a comprehensive and complete city digital twin. Enhancing the efficiency of data processing, promoting the inclusion of socio-economic components of the city, and developing mutual integration between the two counterparts of the digital twin are proposed to be the future research directions to achieve and utilize a completely mirrored city digital twin.
Urban simulations that involve disaster prevention, urban design, and assisted navigation heavily rely on urban geometric models. While large urban areas need a lot of time to be acquired ...terrestrially, government organizations have already conducted massive aerial LiDAR surveys, some even at the national level. This work aims to provide a pipeline for extracting multi-scale point clouds from 2D building footprints and airborne LiDAR data, which depends on whether the points represent buildings, vegetation, or ground. We denoise the roof slopes, match the vegetation, and roughly recreate the building façades frequently hidden to aerial acquisition using a parametric representation of geometric primitives. We then carry out multiple-scale samplings of the urban geometry until a 3D urban representation can be achieved because we annotate the new version of the original point cloud with the parametric equations representing each part. We mainly tested our methodology in a real-world setting - the city of Genoa - which includes historical buildings and is heavily characterized by irregular ground slopes. Moreover, we present the results of urban reconstruction on part of two other cities, Matera, which has a complex morphology like Genoa, and Rotterdam.
•Extraction of multi-scale point clouds from airborne LiDAR data and 2D building footprints.•Generation of simplified/enriched point clouds divided into buildings, ground, and vegetation.•Generation of a cleaned-up point cloud, annotated with parametric equations to allow for reconstruction at various scales.•Reconstruction of the vertical walls of buildings, which are often missing from airborne LiDAR points.•Production of polygonal surfaces of urban areas, suitable for creating LOD2 representations.
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