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Keywords = custom post and core

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14 pages, 412 KB  
Article
Do Novices Struggle with AI Web Design? An Eye-Tracking Study of Full-Site Generation Tools
by Chen Chu, Jianan Zhao and Zhanxun Dong
Multimodal Technol. Interact. 2025, 9(9), 85; https://doi.org/10.3390/mti9090085 - 22 Aug 2025
Viewed by 325
Abstract
AI-powered full-site web generation tools promise to democratize website creation for novice users. However, their actual usability and accessibility for novice users remain insufficiently studied. This study examines interaction barriers faced by novice users when using Wix ADI to complete three tasks: Task [...] Read more.
AI-powered full-site web generation tools promise to democratize website creation for novice users. However, their actual usability and accessibility for novice users remain insufficiently studied. This study examines interaction barriers faced by novice users when using Wix ADI to complete three tasks: Task 1 (onboarding), Task 2 (template customization), and Task 3 (product page creation). Twelve participants with no web design background were recruited to perform these tasks while their behavior was recorded via screen capture and eye-tracking (Tobii Glasses 2), supplemented by post-task interviews. Task completion rates declined significantly in Task 2 (66.67%) and 3 (33.33%). Help-seeking behaviors increased significantly, particularly during template customization and product page creation. Eye-tracking data indicated elevated cognitive load in later tasks, with fixation count and saccade count peaking in Task 2 and pupil diameter peaking in Task 3. Qualitative feedback identified core challenges such as interface ambiguity, limited transparency in AI control, and disrupted task logic. These findings reveal a gap between AI tool affordances and novice user needs, underscoring the importance of interface clarity, editable transparency, and adaptive guidance. As full-site generators increasingly target general users, lowering barriers for novice audiences is essential for equitable access to web creation. Full article
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22 pages, 2538 KB  
Article
Enhancing Supervisory Control with GPenSIM
by Reggie Davidrajuh, Shuanglin Tang and Yuming Feng
Machines 2025, 13(8), 641; https://doi.org/10.3390/machines13080641 - 23 Jul 2025
Viewed by 303
Abstract
Supervisory control theory (SCT), based on Petri nets, offers a robust framework for modeling and controlling discrete-event systems but faces significant challenges in scalability, expressiveness, and practical implementation. This paper introduces General-purpose Petri Net Simulator and Real-Time Controller (GPenSIM), a MATLAB version 24.1.0.2689473 [...] Read more.
Supervisory control theory (SCT), based on Petri nets, offers a robust framework for modeling and controlling discrete-event systems but faces significant challenges in scalability, expressiveness, and practical implementation. This paper introduces General-purpose Petri Net Simulator and Real-Time Controller (GPenSIM), a MATLAB version 24.1.0.2689473 (R2024a) Update 6-based modular Petri net framework, as a novel solution to these limitations. GPenSIM leverages modular decomposition to mitigate state-space explosion, enabling parallel execution of weakly coupled Petri modules on multi-core systems. Its programmable interfaces (pre-processors and post-processors) extend classical Petri nets’ expressiveness by enforcing nonlinear, temporal, and conditional constraints through custom MATLAB scripts, addressing the rigidity of traditional linear constraints. Furthermore, the integration of GPenSIM with MATLAB facilitates real-time control synthesis, performance optimization, and seamless interaction with external hardware and software, bridging the gap between theoretical models and industrial applications. Empirical studies demonstrate the efficacy of GPenSIM in reconfigurable manufacturing systems, where it reduced downtime by 30%, and in distributed control scenarios, where decentralized modules minimized synchronization delays. Grounded in systems theory principles of interconnectedness, GPenSIM emphasizes dynamic relationships between components, offering a scalable, adaptable, and practical tool for supervisory control. This work highlights the potential of GPenSIM to overcome longstanding limitations in SCT, providing a versatile platform for both academic research and industrial deployment. Full article
(This article belongs to the Section Automation and Control Systems)
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35 pages, 10924 KB  
Article
Winding Fault Detection in Power Transformers Based on Support Vector Machine and Discrete Wavelet Transform Approach
by Bonginkosi A. Thango
Technologies 2025, 13(5), 200; https://doi.org/10.3390/technologies13050200 - 14 May 2025
Cited by 1 | Viewed by 761
Abstract
Transformer winding faults (TWFs) can lead to insulation breakdown, internal short circuits, and catastrophic transformer failure. Due to their low current magnitude—particularly at early stages such as inter-turn short circuits, axial or radial displacement, or winding looseness—TWFs often induce minimal impedance changes and [...] Read more.
Transformer winding faults (TWFs) can lead to insulation breakdown, internal short circuits, and catastrophic transformer failure. Due to their low current magnitude—particularly at early stages such as inter-turn short circuits, axial or radial displacement, or winding looseness—TWFs often induce minimal impedance changes and generate fault currents that remain within normal operating thresholds. As a result, conventional protection schemes like overcurrent relays, which are tuned for high-magnitude faults, fail to detect such internal anomalies. Moreover, frequency response deviations caused by TWFs often resemble those introduced by routine phenomena such as tap changer operations, load variation, or core saturation, making accurate diagnosis difficult using traditional FRA interpretation techniques. This paper presents a novel diagnostic framework combining Discrete Wavelet Transform (DWT) and Support Vector Machine (SVM) classification to improve the detection of TWFs. The proposed system employs region-based statistical deviation labeling to enhance interpretability across five well-defined frequency bands. It is validated on five real FRA datasets obtained from operating transformers in Gauteng Province, South Africa, covering a range of MVA ratings and configurations, thereby confirming model transferability. The system supports post-processing but is lightweight enough for near real-time diagnostic use, with average execution time under 12 s per case on standard hardware. A custom graphical user interface (GUI), developed in MATLAB R2022a, automates the diagnostic workflow—including region identification, wavelet-based decomposition visualization, and PDF report generation. The complete framework is released as an open-access toolbox for transformer condition monitoring and predictive maintenance. Full article
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10 pages, 6309 KB  
Article
Stress Distribution in Radicular Dentin with Different Post and Core Materials: A 3D Finite Element Analysis
by Turki S. Alkhallagi, Ghaida’a A. Moria, Dalya F. Al Khunaizi, Mahmoud Alzahrani and Thamer Y. Marghalani
Appl. Sci. 2025, 15(7), 3515; https://doi.org/10.3390/app15073515 - 23 Mar 2025
Viewed by 771
Abstract
This study aims to evaluate the stress distribution of polyetheretherketone (PEEK) and high noble alloy materials in a detailed 3D model of a central incisor using finite element analysis (FEA). A comprehensive 3D model incorporated the crown, crown cement, post and core, post [...] Read more.
This study aims to evaluate the stress distribution of polyetheretherketone (PEEK) and high noble alloy materials in a detailed 3D model of a central incisor using finite element analysis (FEA). A comprehensive 3D model incorporated the crown, crown cement, post and core, post cement, central incisor root, periodontal ligament (PDL), and bone. The PEEK and high noble alloy material properties were input into the model, and the FEA was performed using ABAQUS software. The results showed that while the stresses on the bone, root, and crown increased slightly with the PEEK compared to the high noble alloy, the difference was minimal and attributed to the PEEK’s reduced stiffness. This led to a higher load transfer to surrounding regions around the post. The factor of safety decreased from 16 to 10 when using PEEK, but this reduction was still within acceptable limits and reduced stress-shielding effects. In conclusion, while there was no significant difference in stress magnitudes and distributions between the PEEK and high noble alloys, the PEEK exhibited superior stress-shielding properties, which may offer an advantage in preserving the underlying tooth structure in post and core restorations. Full article
(This article belongs to the Section Applied Dentistry and Oral Sciences)
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29 pages, 5539 KB  
Article
Is Artificial Intelligence a Game-Changer in Steering E-Business into the Future? Uncovering Latent Topics with Probabilistic Generative Models
by Simona-Vasilica Oprea and Adela Bâra
J. Theor. Appl. Electron. Commer. Res. 2025, 20(1), 16; https://doi.org/10.3390/jtaer20010016 - 22 Jan 2025
Cited by 8 | Viewed by 3100
Abstract
Academic publications from the Web of Science Core Collection on “e-business” and “artificial intelligence” (AI) are investigated to reveal the role of AI, extract latent themes and identify potential research topics. The proposed methodology includes relevant graphical representations (trends, co-occurrence networks, Sankey diagrams), [...] Read more.
Academic publications from the Web of Science Core Collection on “e-business” and “artificial intelligence” (AI) are investigated to reveal the role of AI, extract latent themes and identify potential research topics. The proposed methodology includes relevant graphical representations (trends, co-occurrence networks, Sankey diagrams), sentiment analyses and latent topics identification. A renewed interest in these publications is evident post-2018, with a sharp increase in publications around 2020 that can be attributed to the COVID-19 pandemic. Chinese institutions dominate the collaboration network in e-business and AI. Keywords such as “business transformation”, “business value” and “e-business strategy” are prominent, contributing significantly to areas like “Operations Research & Management Science”. Additionally, the keyword “e-agribusiness” recently appears connected to “Environmental Sciences & Ecology”, indicating the application of e-business principles in sustainable practices. Although three sentiment analysis methods broadly agree on key trends, such as the rise in positive sentiment over time and the dominance of neutral sentiment, they differ in detail and focus. Custom analysis reveals more pronounced fluctuations, whereas VADER and TextBlob present steadier and more subdued patterns. Four well-balanced topics are identified with a coherence score of 0.66 using Latent Dirichlet Allocation, which is a probabilistic generative model designed to uncover hidden topics in large text corpora: Topic 1 (29.8%) highlights data-driven decision-making in e-business, focusing on AI, information sharing and technology-enabled business processes. Topic 2 (28.1%) explores AI and Machine Learning (ML) in web-based business, emphasizing customer service, innovation and workflow optimization. Topic 3 (23.6%) focuses on analytical methods for decision-making, using data modeling to enhance strategies, processes and sustainability. Topic 4 (18.5%) examines the semantic web, leveraging ontologies and knowledge systems to improve intelligent systems and web platforms. New pathways such as voice assistance, augmented reality and dynamic marketplaces could further enhance e-business strategies. Full article
(This article belongs to the Topic Data Science and Intelligent Management)
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18 pages, 1205 KB  
Systematic Review
Dimensional Accuracy of Intraoral Scanners in Recording Digital Impressions of Post and Core Preparations: A Systematic Review
by Saeed M. Alqahtani, Mohammed Salman Almalki, Mai Almarzouki, Saad Saleh AlResayes, Nisreen Nabiel Hassan, Arwa Jaber I. Mohana, Majed S. Altoman and Mohammed E. Sayed
Diagnostics 2024, 14(24), 2890; https://doi.org/10.3390/diagnostics14242890 - 23 Dec 2024
Viewed by 1659
Abstract
Background: This study aims to perform a review by selecting, analyzing, and evaluating articles that discuss the accuracy of intraoral scanners (IOSs) in recording post space compared to conventional impression-making techniques. Methods: The review question framed using the PITR framework (participant, index test, [...] Read more.
Background: This study aims to perform a review by selecting, analyzing, and evaluating articles that discuss the accuracy of intraoral scanners (IOSs) in recording post space compared to conventional impression-making techniques. Methods: The review question framed using the PITR framework (participant, index test, targeted condition, and reference standard) is as follows: What is the dimensional accuracy (T) of impressions made using intraoral scanners (I) for post space (P) compared to impressions made using conventional techniques and digitalized using extraoral scanners (R)? Four electronic databases were searched using pre-set keywords. The guidelines and strategies recommended by PRISMA formed the basis for planning, executing, and documenting this systematic review. QUADAS-2 was used to critically analyze the quality of all the selected articles. Results: After excluding ineligible articles, the end synthesis has nine studies (n = 9) for qualitative analysis. All nine evaluated studies were found to be at risk of bias, with high or unclear risk in one or more domains. Three out of nine evaluated studies had unclear concerns regarding the applicability, and the remaining six had low concerns. In all the included studies, the IOSs were reported to have deviations in accuracy compared to the conventional techniques for making digital impressions of post space. Conclusions: The accuracy of IOSs was found to be inversely proportional to the length of post space and directly proportional to the diameter of post space. IOSs, when used adequately in short post spaces, can be an alternative to conventional impression-making for making custom posts and cores. Full article
(This article belongs to the Special Issue New Possibilities for Digital Diagnosis and Planning in Dentistry)
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11 pages, 1885 KB  
Article
Evaluation of Internal Fit in Custom-Made Posts and Cores Fabricated with Fully Digital Versus Conventional Techniques
by Eric Jensen and Shariel Sayardoust
J. Funct. Biomater. 2024, 15(12), 389; https://doi.org/10.3390/jfb15120389 - 22 Dec 2024
Cited by 1 | Viewed by 1426
Abstract
Objective: This study aimed to assess and compare the internal fit of custom-made posts and cores fabricated using digital impressions (DI) and conventional vinyl polysiloxane (VPS) impressions in restorative dentistry. Materials and Methods: A typodont tooth model, simulating the anatomy of the root [...] Read more.
Objective: This study aimed to assess and compare the internal fit of custom-made posts and cores fabricated using digital impressions (DI) and conventional vinyl polysiloxane (VPS) impressions in restorative dentistry. Materials and Methods: A typodont tooth model, simulating the anatomy of the root canal of a central incisor, was utilized for the study. Two groups were formed, Group A and Group B, and each group provided a total of 18 impressions of two types: DIs and VPS impressions. In Group A, posts and cores (PCs) were fabricated using Selective Laser Melting (SLM) from the DIs. Meanwhile, in Group B, conventionally cast (CC) PCs were created from the VPS impressions. Silicone replicas of the internal surfaces were produced, and measurements were made at seven different points for each group. A statistical analysis was performed to assess the differences in internal fit between the two impression techniques. Results: The results revealed a statistically significant difference in mean internal fit between Group A (DI and SLM) and Group B (VPS and CC), with Group A exhibiting a mean internal fit of 182.6 µm and Group B showing a mean of 205.9 µm. While both groups demonstrated considerable variability in internal fit measurements, the digital impression technique showed promise for achieving superior internal fit, with a significantly greater fit for measuring points on sides and the most apical part of the post for Group A. Variations were observed across different measuring points, emphasizing the impact of impression technique on specific regions within the tooth. Conclusion: This study contributes to the growing body of knowledge in digital dentistry by highlighting the potential benefits of DIs in achieving a superior internal fit for custom-made PCs. Clinicians may consider the advantages of digital techniques to enhance the precision of their restorative procedures, although further research is warranted to evaluate the clinical impact of these findings. Full article
(This article belongs to the Section Dental Biomaterials)
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36 pages, 3858 KB  
Article
Exploring the Dynamics of Canine-Assisted Interactions: A Wearable Approach to Understanding Interspecies Well-Being
by Timothy R. N. Holder, Colt Nichols, Emily Summers, David L. Roberts and Alper Bozkurt
Animals 2024, 14(24), 3628; https://doi.org/10.3390/ani14243628 - 16 Dec 2024
Cited by 1 | Viewed by 1947
Abstract
Canine-assisted interactions (CAIs) have been explored to offer therapeutic benefits to human participants in various contexts, from addressing cancer-related fatigue to treating post-traumatic stress disorder. Despite their widespread adoption, there are still unresolved questions regarding the outcomes for both humans and animals involved [...] Read more.
Canine-assisted interactions (CAIs) have been explored to offer therapeutic benefits to human participants in various contexts, from addressing cancer-related fatigue to treating post-traumatic stress disorder. Despite their widespread adoption, there are still unresolved questions regarding the outcomes for both humans and animals involved in these interactions. Previous attempts to address these questions have suffered from core methodological weaknesses, especially due to absence of tools for an efficient objective evaluation and lack of focus on the canine perspective. In this article, we present a first-of-its-kind system and study to collect simultaneous and continuous physiological data from both of the CAI interactants. Motivated by our extensive field reviews and stakeholder feedback, this comprehensive wearable system is composed of custom-designed and commercially available sensor devices. We performed a repeated-measures pilot study, to combine data collected via this system with a novel dyadic behavioral coding method and short- and long-term surveys. We evaluated these multimodal data streams independently, and we further correlated the psychological, physiological, and behavioral metrics to better elucidate the outcomes and dynamics of CAIs. Confirming previous field results, human electrodermal activity is the measure most strongly distinguished between the dyads’ non-interaction and interaction periods. Valence, arousal, and the positive affect of the human participant significantly increased during interaction with the canine participant. Also, we observed in our pilot study that (a) the canine heart rate was more dynamic than the human’s during interactions, (b) the surveys proved to be the best indicator of the subjects’ affective state, and (c) the behavior coding approaches best tracked the bond quality between the interacting dyads. Notably, we found that most of the interaction sessions were characterized by extended neutral periods with some positive and negative peaks, where the bonded pairs might display decreased behavioral synchrony. We also present three new representations of the internal and overall dynamics of CAIs for adoption by the broader field. Lastly, this paper discusses ongoing options for further dyadic analysis, interspecies emotion prediction, integration of contextually relevant environmental data, and standardization of human–animal interaction equipment and analytical approaches. Altogether, this work takes a significant step forward on a promising path to our better understanding of how CAIs improve well-being and how interspecies psychophysiological states can be appropriately measured. Full article
(This article belongs to the Special Issue Animal–Computer Interaction: New Horizons in Animal Welfare)
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11 pages, 3467 KB  
Article
Adaptation of 3D-Printed and Milled Titanium Custom Post and Core
by Abdulaziz A. Alzaid, Sarah Bukhari, Mathew T. Kattadiyil, Hatem Alqarni, Abdulaziz A. AlHelal, Khalid K. Alanazi, Montry S. Suprono, Rami Jekki and Erik F. Sahl
Prosthesis 2024, 6(6), 1448-1458; https://doi.org/10.3390/prosthesis6060105 - 2 Dec 2024
Viewed by 1178
Abstract
Background/Objectives: The purpose of this in vitro study was to evaluate and compare the internal adaptation and cement film thickness of cast-gold custom post and core (CPC), three-dimensionally (3D)-printed titanium (Ti) CPC, and milled Ti CPC. Methods: Forty-eight 3D printed resin models, simulating [...] Read more.
Background/Objectives: The purpose of this in vitro study was to evaluate and compare the internal adaptation and cement film thickness of cast-gold custom post and core (CPC), three-dimensionally (3D)-printed titanium (Ti) CPC, and milled Ti CPC. Methods: Forty-eight 3D printed resin models, simulating a tooth prepared to receive a CPC, were fabricated. Models were randomly assigned to one of three groups (n = 16 per group): (A) cast-gold CPC (control group), (B) 3D-printed Ti CPC, and (C) milled Ti CPC. Following the manufacturing of CPCs, each CPC was cemented using dual-cure polymerizing resin cement. Then, each model/post-and-core assembly was sectioned at the coronal, middle, and apical thirds of the post at a specific point. Each section was photographed using a microscope in a standardized setting (25×). The pixel count for cement surface area was calculated for each image using Adobe Photoshop software. Descriptive statistics of the mean and standard deviation of the cement film thickness around posts were calculated. Kruskal–Wallis and Dwass–Steel–Critchlow–Fligner tests were used for statistical analysis, with a significance level of α = 0.05. Results: Pairwise comparisons in the coronal section revealed a statistically significant difference (p < 0.05) between groups A and B and groups B and C. In the middle section, there was a statistically significant difference (p < 0.05) between groups A and B only. In the apical section, there was a statistically significant difference (p < 0.05) between all groups. Conclusions: Within the limitation of the present study, neither 3D printed nor milled Ti CPC could achieve comparable cement film thickness to cast-gold CPC in all three sections. Cast-gold CPC cement film thickness was found to be more reduced and consistent, thus having superior internal adaptation to 3D-printed and milled Ti CPCs. Full article
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13 pages, 9090 KB  
Article
A Lightweight and High Yield Complementary Metal-Oxide Semiconductor True Random Number Generator with Lightweight Photon Post-Processing
by Chi Trung Ngo, Hyun Woo Ko, Ji Woo Choi, Jae-Won Nam and Jong-Phil Hong
Sensors 2024, 24(23), 7502; https://doi.org/10.3390/s24237502 - 25 Nov 2024
Cited by 2 | Viewed by 1203
Abstract
This paper introduces a novel TRNG architecture that employs a wave converter to generate random outputs from the jitter noise in a customized ring oscillator (RO). Using a current-starved inverter, the proposed RO offers the option of operating three different oscillation frequencies from [...] Read more.
This paper introduces a novel TRNG architecture that employs a wave converter to generate random outputs from the jitter noise in a customized ring oscillator (RO). Using a current-starved inverter, the proposed RO offers the option of operating three different oscillation frequencies from a single oscillator. To assess its performance, the core TRNG proposed in this work was designed with multiple samples, employing various transistor sizes for 28 nm CMOS processes. The measurements show that only a small number of measured TRNG samples passed the randomness NIST SP 800-22 tests, which is a common problem, not only with the proposed TRNG but also with other TRNG structures. To solve this issue, a lightweight post-processing algorithm using the Photon hash function was newly applied to the proposed TRNGs topology. The lightweight Photon hash function-based post-processing was implemented with the proposed TRNG topology in a 28 nm CMOS process. The design occupies 16,498 µm2, with a throughput of 0.0142 Mbps and power consumption of 31.12 mW. Measurements showed significant improvement, with a 50% increase in chips passing the NIST SP 800-22 tests. Compared with the conventional DRBG post-processing method, the proposed lightweight Photon post-processing reduces area occupation by five times and power consumption by 65%. Full article
(This article belongs to the Special Issue CMOS-Integrated Optoelectronics for Sensing Applications)
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9 pages, 525 KB  
Article
Clinical Acceptance of Digitally Produced Zirconia and Metal Post and Cores, Based on the Impression Method
by Paula Perlea, Cosmin Stefanescu and Alexandru Eugen Petre
Clin. Pract. 2024, 14(6), 2533-2541; https://doi.org/10.3390/clinpract14060199 - 20 Nov 2024
Viewed by 1486
Abstract
Background: The existing literature predominantly examines post and core assessments post-cementation, neglecting the critical pre-cementation phase. Research on the clinical acceptance of dental posts received from dental laboratories before cementation is notably lacking. This study investigates the percentage of zirconia and metal dental [...] Read more.
Background: The existing literature predominantly examines post and core assessments post-cementation, neglecting the critical pre-cementation phase. Research on the clinical acceptance of dental posts received from dental laboratories before cementation is notably lacking. This study investigates the percentage of zirconia and metal dental posts that are deemed suitable for cementation by clinicians, among the total received from the dental laboratory. Additionally, it aims to examine whether this percentage varies based on the type of impression made by the clinician: digital impression versus conventional impression. Methods: This article introduces the application of computer-aided design-computer-aided manufacturing (CAD-CAM) technology for manufacturing customized zirconia and Cobalt–Chromium (Co-Cr) post and cores. Intraoral scanning is employed to capture the canal anatomy. In contrast to the traditional casting process, a three-dimensional (3D) metal printer machine is utilized to 3D print the metal post and core from Co-Cr, resulting in enhanced toughness and superior adaptability to the canal. Two null hypotheses were formulated, investigating the clinical acceptance of zirconia and metal posts obtained through traditional versus digital impressions. Results: Among 577 post and cores, 95% of metal posts from both impression methods received clinical approval. However, for zirconia posts, a significantly higher acceptance rate (95% versus 88%) was observed for those from traditional impressions. The Chi-squared test yielded a p-value < 0.05, underscoring the clinical superiority of conventionally obtained zirconia posts and supporting the null hypothesis for metal posts. Conclusions: A significantly higher acceptance rate is apparent among zirconia post and cores manufactured through conventional impressions, in contrast to zirconia post and cores produced via digital impressions. No statistically significant difference was identified between metal post and cores obtained through digital impressions and those acquired through conventional impressions. Full article
(This article belongs to the Special Issue Clinical Outcome Research in the Head and Neck)
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22 pages, 3454 KB  
Article
An Applied Analysis of Securing 5G/6G Core Networks with Post-Quantum Key Encapsulation Methods
by Paul Scalise, Robert Garcia, Matthew Boeding, Michael Hempel and Hamid Sharif
Electronics 2024, 13(21), 4258; https://doi.org/10.3390/electronics13214258 - 30 Oct 2024
Cited by 4 | Viewed by 3797
Abstract
Fifth Generation (5G) cellular networks have been adopted worldwide since the rollout began around 2019. It brought with it many innovations and new services, such as Enhanced Mobile Broadband (eMBB), Ultra Reliable and Low-Latency Communications (URLLC), and Massive Internet of Things (mIoT). Furthermore, [...] Read more.
Fifth Generation (5G) cellular networks have been adopted worldwide since the rollout began around 2019. It brought with it many innovations and new services, such as Enhanced Mobile Broadband (eMBB), Ultra Reliable and Low-Latency Communications (URLLC), and Massive Internet of Things (mIoT). Furthermore, 5G introduced a more scalable approach to network operations using fully software-based Virtualized Network Functions (VNF) in Core Networks (CN) rather than the prior hardware-based approach. However, while this shift towards a fully software-based system design provides numerous significant benefits, such as increased interoperability, scalability, and cost-effectiveness, it also brings with it an increased cybersecurity risk. Security is crucial to maintaining trust between vendors, operators, and consumers. Cyberattacks are rapidly increasing in number and sophistication, and we are seeing a shift towards zero-trust approaches. This means that even communications between VNFs inside a 5G core must be scrutinized and hardened against attacks, especially with the advent of quantum computers. The National Institute of Standards and Technology (NIST), over the past 10 years, has led efforts to standardize post-quantum cryptography (PQC) to protect against quantum attacks. This paper covers a custom implementation of the open-source free5GC CN, to expand its HTTPS capabilities for VNFs by introducing PQC Key Encapsulation Methods (KEM) for Transport Layer Security (TLS) v1.3. This paper provides the details of this integration with a focus on the latency of different PQC KEMs in initial handshakes between VNFs, on packet size, and the implications in a 5G environment. This work also conducts a security comparison between the PQC-equipped free5GC and other open-source 5G CNs. The presented results indicate a negligible increase in UE connection setup duration and a small increase in connection setup data requirements, strongly indicating that PQC KEM’s benefits far outweigh any downsides when integrated into 5G and 6G core services. To the best of our knowledge, this is the first work incorporating PQC into an open-source 5G core. Furthermore, the results from this effort demonstrate that employing PQC ciphers for securing VNF communications results in only a negligible impact on latency and bandwidth usage, thus demonstrating significant benefits to 5G cybersecurity. Full article
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16 pages, 3351 KB  
Article
The Accuracy of Custom-Made Milled Metal Posts as Compared to Conventional Cast Metal Posts
by Tabarak M. AL-Rubaye and Emad S. Elsubeihi
Dent. J. 2024, 12(10), 309; https://doi.org/10.3390/dj12100309 - 28 Sep 2024
Cited by 1 | Viewed by 1546
Abstract
Aim: The aim of this study was to compare the fitting accuracy of custom-made metal posts and cores fabricated by half-digital and milling technique to that of conventional cast posts fabricated by direct technique. Methods: Sixteen extracted single-rooted teeth were endodontically treated followed [...] Read more.
Aim: The aim of this study was to compare the fitting accuracy of custom-made metal posts and cores fabricated by half-digital and milling technique to that of conventional cast posts fabricated by direct technique. Methods: Sixteen extracted single-rooted teeth were endodontically treated followed by post space preparation. A direct resin post and core pattern was made for each tooth and used for the fabrication of two posts (n = 16). Each post resin pattern was digitized with a laboratory scanner and used for the fabrication of a milled cobalt–chrome (Co–Cr) alloy post, while the direct resin pattern, after scanning, was cast in a Co–Cr alloy to produce a cast post. Each post was seated on its respective tooth and evaluated using microcomputed tomography. The following variables were evaluated: total space volume between the post and root canal, the volume and distance of the apical gap between each post and the remaining apical root canal filling, as well as the distance and surface area of the space between the post and lateral root canal wall at four determined points along the length of each post. Results: The results revealed that half-digital and milled posts had a statistically significantly higher total space volume (p < 0.05), apical gap volume (p < 0.02) and distance (p < 0.02), as well as a higher surface area of space between the post and root canal wall at the cervical area as compared to the cast post (p < 0.05). Conclusions: This study demonstrated that the fitting accuracy of cast posts was more accurate than posts fabricated with half-digital and milling technique. Full article
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15 pages, 1166 KB  
Review
Assessment of CAD/CAM Fabrication Technologies for Post and Core Restorations—A Narrative Review
by Mariya Dimitrova, Angelina Vlahova and Rada Kazakova
Medicina 2024, 60(5), 748; https://doi.org/10.3390/medicina60050748 - 30 Apr 2024
Cited by 3 | Viewed by 2609
Abstract
The primary objective of this study is to conduct a comprehensive review of the existing literature that discusses research on post and core restorations, covering aspects such as their composition, manufacturing methods, and clinical effectiveness. The methodology employed in this review encompasses the [...] Read more.
The primary objective of this study is to conduct a comprehensive review of the existing literature that discusses research on post and core restorations, covering aspects such as their composition, manufacturing methods, and clinical effectiveness. The methodology employed in this review encompasses the implementation of a well-defined search strategy, the establishment of criteria for inclusion and exclusion, and the selection of relevant studies to summarize their findings. To gather relevant literature published between 1993 and 2023, the research team conducted separate searches on PubMed, Web of Science, and Embase databases. In total, 168 titles were initially retrieved from these electronic databases. By applying the predefined exclusion criteria, the researchers identified 73 articles that specifically address the conventional and computer-aided design/computer-aided manufacturing (CAD/CAM) technologies employed in post and core restorations. These treatments are commonly employed to restore teeth that have received endodontic therapy and subsequently experienced loss of dental structure. The development of computerized technology for the creation of customized posts and cores has emerged as a straightforward and efficient alternative to traditional methods. The review synthesizes papers discussing the techniques and materials involved in CAD/CAM-based construction of post and cores. It explores strategies for restoring endodontically treated teeth, highlighting both direct and indirect approaches. Commonly mentioned materials include zirconia, composite resin, and hybrid ceramics. Despite the limited literature on CAD/CAM post and core procedures, the review emphasizes the necessity of further research to assess long-term outcomes and efficacy. Additionally, it suggests including implications for future research and clinical recommendations to enhance the depth and practical relevance of the review. Full article
(This article belongs to the Special Issue Management of Prosthetic Dentistry and Oral Biology)
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21 pages, 6295 KB  
Article
Self-Centering Precast Unit as Energy Dissipation Members in Precast Segmental Bridge Columns
by Amr M. A. Moussa, Mohamed F. M. Fahmy, Fusheng Niu, Xin Wang and Zhishen Wu
Buildings 2024, 14(2), 438; https://doi.org/10.3390/buildings14020438 - 5 Feb 2024
Cited by 3 | Viewed by 2183
Abstract
This research aims to present a new generation of seismic-resisting systems designed for precast reinforced concrete (RC) bridge piers in modern sustainable cities to withstand moderate to high seismic activity. The proposed system consists of two self-centering (SC) systems operating in parallel to [...] Read more.
This research aims to present a new generation of seismic-resisting systems designed for precast reinforced concrete (RC) bridge piers in modern sustainable cities to withstand moderate to high seismic activity. The proposed system consists of two self-centering (SC) systems operating in parallel to bring together all features of the required resiliency during a seismic action. The first/main system is a hollow core precast segmental bridge column, and the second is composed of an SC precast unit and energy dissipation (ED) steel reinforcements positioned in the main pier segment’s hollow core. To study the performance of the proposed system, a finite element model was first developed to capture the behavior of experimentally tested precast bridge columns. After validation, the created model was systematically studied to investigate the performance of the entire proposed system under cyclic loading. The effects of three parameters related to the ED system were investigated, including the reinforcement ratio, the unbonded length of ED bars, and the SC post-tensioned force ratio. Furthermore, the impact of FRP wrapping on the lower part of the core column of the ED system was also investigated. An analytical model predicting the characteristic points of the lateral response of the proposed system based on the superposition concept is also proposed. The FE results showed that the entire proposed system is a new design-based resilient system with the ability to dissipate energy without compromising the SC capacity of the main resisting system. Compared to the typical precast hollow core segmental column, a 6% reinforcement ratio of the ED unit can cause a 60% increase in lateral resistance and a 220% increase in the ED capacity. The analytical model can successfully be applied in the design of the proposed system to provide customized ED capabilities and controlled lateral resistance. Full article
(This article belongs to the Section Building Structures)
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