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Trajectory generation for ROI expansion in dental CBCT imaging: An out-of-FOV ROI annotation guided arc scan-based approach

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Computational and Structural Biotechnology Journal 2025年 28卷 211-216页

作者： S M Ragib Shahriar Islam Ander Biguri Claudio Landi Giovanni Di Domenico Pascal Grün Cristina Sarti Carola-Bibiane Schönlieb Dritan Turhani Gernot Kronreif Wolfgang Birkfellner Sepideh Hatamikia Austrian Center for Medical Innovation and Technology Wiener Neustadt Austria Center for Medical Physics and Biomedical Engineering Medical University Vienna Vienna Austria Clinical AI-Research in Omics and Medical Data Science (CAROM) Group Department of Medicine Danube Private University (DPU) Krems Austria Department of Applied Mathematics and Theoretical Physics University of Cambridge Cambridge United Kingdom SeeThrough SrL Via Bolgara 2 Brusaporto (BG) Italy Department of Physics and Earth Science University of Ferrara Ferrara Italy Center for Oral and Maxillofacial Surgery Department of Dentistry Faculty of Medicine and Dentistry Danube Private University (DPU) Krems Austria

This study introduces a novel optimization approach for source-detector trajectories, designed to simultaneously extend the small dental CBCT field of view (FOV) at specific regions of interest (ROIs) while reducing radiation dose. The proposed algorithm automatically customizes and produces a mechanically feasible arc-based scan trajectory to target predefined ROIs, expanding the FOV beyond the standard range while utilizing only the necessary projections to reconstruct the region of interest, rather than those required for reconstruction of the entire volume. This approach enables a significant reduction in the number of projections. Both qualitative and quantitative analyses, including peak signal-to-noise ratio (PSNR) values greater than 30 dB and structural similarity index measure (SSIM) scores above 0.9, demonstrate that the method successfully enhances the FOV while maintaining high image quality. Notably, the approach achieves a significant reduction in the number of projections up to 47% compared to the conventional limited-angle circular trajectory. This is the first study to explore the simultaneous extension of the FOV and radiation dose reduction in dental CBCT imaging, providing a promising solution for improving clinical outcomes and treatment planning in next-generation CBCT systems.

关键词： Dental CBCT Image reconstruction Field of view Trajectory optimization Interventional radiology Dose reduction

Lossless Compression Technique For ECG Signals Using A-law Companding Algorithm

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Lossless Compression Technique For ECG Signals Using A-law C...

Innovative Research in applied Science, engineering and Technology (IRASET),Conference on

作者： Mustapha El Hanine Hicham Ouldzira Abdelghani Boudaoud Elhassane Abdelmounim Department of Biomedical Instrumentation and Medical Physics Laboratory of Health Sciences and Technologies Higher Institute of Health Sciences Hassan First University of Settat Settat Morocco Department of Industrial Engineering Laboratory of Engineering Industrial Management and Innovation (Faculty of Sciences and Technology Settat) National School of Applied Sciences Cadi Ayyad University Safi Morocco Department of Mechatronics Laboratory of Engeneering and Applied Physics High School of Technology Sultan Moulay Slimane University Beni Mellal Morocco Department of Applied Physics Laboratory of System Analysis and Information Technology Faculty of Sciences and Technology Hassan First University Settat Morocco

In this work, we present a lossless compression technique based on the use of the A-law companding algorithm, associated with the inter-leads correlation to compress ECG signals by reducing the dynamic range and number of encoded signals. Experiments are conducted on the selected records from the PTB Arrhythmia Database, and the performance is evaluated using the compression ratio (CR) and the percent root mean square difference (PRD). the results show that this technique efficiently retains pathological informations, whether for patients in normal condition or with arrhythmias, a total compression ratio CR of 4.92 is achieved with a PRD of 0 %.

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Nernst-Ettingshausen effect in thin Pt and W films at low temperatures

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arXiv 2023年

作者： Luo, Renjie Legvold, Tanner J. Chen, Liyang Natelson, Douglas Department of Physics and Astronomy Rice University HoustonTX77005 United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Electrical and Computer Engineering Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States

As spin caloritronic measurements become increasingly common techniques for characterizing material properties, it is important to quantify potentially confounding effects. We report measurements of the Nernst-Ettingshausen response from room temperature to 5 K in thin film wires of Pt and W, metals commonly used as inverse spin Hall detectors in spin Seebeck characterization. Johnson-Nyquist noise thermometry is used to assess the temperature change of the metals with heater power at low temperatures, and the thermal path is analyzed via finite-element modeling. The Nernst-Ettingshausen response of W is found to be approximately temperature-independent, while the response of Pt increases at low temperatures. These results are discussed in the context of theoretical expectations and the possible role of magnetic impurities in Pt. Copyright © 2023, The Authors. All rights reserved.

关键词： Inverse problems

Construction of a Low-Power Rating FM Transmitter Radio with Audio Console for Community Broadcast and Security Alert

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Construction of a Low-Power Rating FM Transmitter Radio with...

Science, engineering and Business for Sustainable Development Goals (SEB-SDG), International Conference on

作者： Adegbenro Sunday Ajani Olusoji Amos Ogunbode Godwin Babatunde Egbeyale Charity Segun Odeyemi Adedoja Feyisayo Babalola Peter Olaoluwa Oyero Department of Physics and Materials Science Faculty of Pure and Applied Sciences Kwara State University Ilorin Kwara State Nigeria Department of Biomedical Engineering Western University London Ontario Canada Department of Electrical Electronics Engineering School of Engineering and Engineering Technology Federal. University of Technology Akure Ondo State Nigeria Department of Basic Sciences Adeleke University Ede Osun State Nigeria

The security challenges experienced in different communities of Nigeria require initiatives from every stakeholder, hence the development of this miniaturized FM transmission console for information dissemination within a localized community. The early transmitter for radio broadcasting was so bulky and laborious that they occupied large space and heavy circuitry. The circuits were mainly designed with valves and other active components, which are responsible for the large size. With the advent of semiconductor materials such as transistors and integrated circuits, electronic equipments are now becoming miniaturized such that small transmitters are now becoming handy and compact. In line with this, a complete radio broadcasting equipment that is compact and locally designed is constructed in this research. The system units are of two categories namely: the audio console for processing voice with music mixer and the transmitter unit where the center frequency is generated. This project is aimed at serving community such as Estates or villages for broadcasting urgent information using a small radio broadcasting FM transmitting at 107.0 MHz with a power rating of 1 watt and covers a distance of 1 kilometer irrespective of directivity. The output audio signal was tested for different hours of the day and production was received with noticeable voice output. The radio broadcasting transmitter can also be used to disseminate information within large industries, hospitals and universities. The constructed device is recommended for security alerts in areas where security challenges are currently taking place in the Nigeria.

关键词： Frequency modulation Semiconductor materials Radio transmitters Vegetation Valves Security Transistors

Magnetic Exciton-Polariton with Strongly Coupled Atomic and Photonic Anisotropies

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arXiv 2023年

作者： Li, Qiuyang Xie, Xin Alfrey, Adam Beach, Christiano W. McLellan, Nicholas Lu, Yang Hu, Jiaqi Liu, Wenhao Dhale, Nikhil Lv, Bing Zhao, Liuyan Sun, Kai Deng, Hui Department of Physics University of Michigan Ann ArborMI48109 United States Applied Physics Program University of Michigan Ann ArborMI48109 United States Department of Electrical Engineering and Computer Science University of Michigan Ann ArborMI48109 United States Department of Physics University of Texas at Dallas RichardsonTX75080 United States

Anisotropy plays a key role in science and engineering. However, the interplay between the material and engineered photonic anisotropies has hardly been explored due to the vastly different length scales. Here we demonstrate a matter-light hybrid system, exciton-polaritons in a 2D antiferromagnet, CrSBr, coupled with an anisotropic photonic crystal (PC) cavity, where the spin, atomic lattice, and photonic lattices anisotropies are strongly correlated, giving rise to unusual properties of the hybrid system and new possibilities of tuning. We show exceptionally strong coupling between engineered anisotropic optical modes and anisotropic excitons in CrSBr, which is stable against excitation densities a few orders of magnitude higher than polaritons in isotropic materials. Moreover, the polaritons feature a highly anisotropic polarization tunable by tens of degrees by controlling the matter-light coupling via, for instance, spatial alignment between the material and photonic lattices, magnetic field, temperature, cavity detuning and cavity quality-factors. The demonstrated system provides a prototype where atomic- and photonic-scale orders strongly couple, opening opportunities of photonic engineering of quantum materials and novel photonic devices, such as compact, on-chip polarized light source and polariton laser. © 2023, CC BY-NC-ND.

关键词： Anisotropy

Emergent Moiré fringes in direct-grown quasicrystal

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arXiv 2024年

作者： Li, Jingwei Bao, Kejie Sun, Honglin Yan, Xingxu Huang, Ting Zhang, Qicheng Zhou, Yaoqiang Liu, Zhenjing Das, Paul Masih You, Jiawen Zhao, Jiong Xu, Jianbin Pan, Xiaoqing Mi, Yongli Zhu, Junyi Gao, Zhaoli Department of Biomedical Engineering The Chinese University of Hong Kong Hong Kong Department of Chemical and Biological Engineering The Hong Kong University of Science and Technology Hong Kong State Key Laboratory of Surface Physics Department of Physics Fudan University Shanghai200433 China Department of Physics The Chinese University of Hong Kong Hong Kong Department of Materials Science and Engineering University of California - Irvine IrvineCA92697 United States Research Center for Industries of the Future Westlake University Zhejiang Hangzhou310030 China Key Laboratory of 3D Micro/nano Fabrication and Characterization of Zhejiang Province School of Engineering Westlake University Zhejiang Hangzhou310030 China Department of Electronic Engineering The Chinese University of Hong Kong Hong Kong Department of Physics and Astronomy University of Pennsylvania Philadelphia19104 United States Department of Applied Physics The Hong Kong Polytechnic University Hong Kong

Quasicrystals represent a category of rarely structured solids that challenge traditional periodicity in crystal materials. Recent advancements in the synthesis of two-dimensional (2D) van der Waals materials have paved the way for exploring the unique physical properties of these systems. Here, we report on the synthesis of 2D quasicrystals featuring 30° alternating twist angles between multiple graphene layers, using chemical vapor deposition (CVD). Strikingly, we observed periodic Moiré patterns in the quasicrystal, a finding that has not been previously reported in traditional alloy-based quasicrystals. The Moiré periodicity, varying with the parity of the constituent layers, aligns with the theoretical predictions that suggest a stress cancellation mechanism in force. The emergence of Moiré fringes is attributed to the spontaneous mismatched lattice constant in the oriented graphene layers, proving the existence of atomic relaxation. This phenomenon, which has been largely understudied in graphene systems with large twist angles, has now been validated through our use of scanning transmission electron microscopy (STEM). Our CVD-grown Moiré quasicrystal provides an ideal platform for exploring the unusual physical properties that arise from Moiré periodicity within quasicrystals. Copyright © 2024, The Authors. All rights reserved.

关键词： Graphene

A Dynamic SDN-based Privacy-Preserving Approach for Smart City Using Trust Technique 9

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A Dynamic SDN-based Privacy-Preserving Approach for Smart Ci...

9th Iranian Joint Congress on Fuzzy and Intelligent Systems, CFIS 2022

作者： Alzubi, Jafar A. Movassagh, AliAkbar Gheisari, Mehdi Najafabadi, Hamid Esmaeili Abbasi, Aaqif Afzaal Liu, Yang Pingmei, Zhou Izadpanahkakhk, Mahdieh Najafabadi, AmirHossein Pourishaban Al-Balqa Applied University Faculty of Engineering Salt Jordan Tehran University of Medical Sciences School of Medicine Department of Medical Physics and Biomedical Engineering Tehran Iran Islamic Azad University Young Researchers and Elite Club Parand Branch Parand Iran University of Calgary Canada Foundation University Department of Software Engineering Islamabad44000 Pakistan Harbin Institute of Technology Department of Computer Science and Technology Shenzhen China Shenzhen BKD Company Shenzhen China La Sapienza University DIET Department Rome Italy University of Yazd Department of Electrical and Computer Engineering Yazd Iran

ISBN: (纸本)9781665478724

A smart city is an Internet-based application of things that automates city management with no need for human interference. Exchanging data via devices obviate some challenges in intelligent cities. In a smart city, Internet-of-Things (IoT) devices may detect sensitive data, posing a risk of privacy violation and system harm. We discover that existing solutions are either too expensive or ineffective at limiting unintended disclosure of sensitive data to build a dependable, smart city. The fact that they create static surroundings is the fundamental reason behind this. Software-Defined Networking (SDN) technology has recently evolved to configure the network for performance and monitoring improvement. This study offers a work-in-progress that uses the SDN to protect the privacy of IoT devices by creating a dynamic SDN-based privacy-preserving ecology. The mechanism of the SDN controller performs under the nodes' mutual trust;it chooses various routes from the IoT device to the Cloud space destination dependent on the level of confidence. The packet is re-routed if the SDN controller identifies a device that does not trust its neighbor. Then it instructs the owner to deliver data over a different path. To demonstrate its improved performance, we are currently evaluating it from the perspective of overhead criteria in the future. © 2022 IEEE.

关键词： Smart city

Terahertz phonon polariton concentrator based on perovskite oxides

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Terahertz phonon polariton concentrator based on perovskite ...

Conference on Lasers and Electro-Optics (CLEO)

作者： Rui Xu Tong Lin Jiaming Luo Xiaotong Chen Elizabeth R. Blackert Alyssa R. Moon Khalil M. JeBailey Hanyu Zhu Department of Materials Science and Nano Engineering Rice University Houston U.S.A. Applied Physics Graduate Program Rice University Houston U.S.A. Nanotechnology Research Experience for Undergraduates (Nano REU) Program Rice University Houston U.S.A.

We report the experimental demonstration of surface phonon-polaritonic devices in a broad spectral range of 7-13 THz based on SrTiO 3 . We designed planar ultrafast concentrators that amplifies transient electric fiel... 详细信息

ISBN: (纸本)9781957171258

关键词： Concentrators Electric fields Fast Fourier transforms Field enhancement Fused silica Second harmonic generation

Metallization of colloidal crystals

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arXiv 2021年

作者： Ehlen, Ali Lopez-Rios, Hector de la Cruz, Monica Olvera Applied Physics Program Northwestern University Department of Materials Science and Engineering Northwestern University

Colloidal crystals formed by size-asymmetric binary particles co-assemble into a wide variety of colloidal compounds with lattices akin to ionic crystals. Recently, a transition from a compound phase with a sublattice of small particles to a metal-like phase in which the small particles are delocalized has been predicted computationally and observed experimentally. In this colloidal metallic phase, the small particles roam the crystal maintaining the integrity of the lattice of large particles, as electrons do in metals. A similar transition also occurs in superionic crystals, termed sublattice melting. Here, we use energetic principles and a generalized molecular dynamics (MD) model of a binary system of functionalized nanoparticles (NPs) to analyze the transition to sublattice delocalization in different co-assembled crystal phases as a function of temperature (T), number of grafted chains on the small particles, and number ratio between the small and large particles ns:nl. We find that ns:nl is the primary determinant of crystal type due to energetic interactions and interstitial site filling, while the number of grafted chains per small particle determines the stability of these crystals. We observe first-order sublattice delocalization transitions as T increases, in which the host lattice transforms from low- to high-symmetry crystal structures, including A20 → BCT → BCC, Ad → BCT → BCC, and BCC → BCC/FCC → FCC transitions and lattices. Analogous sublattice transitions driven primarily by lattice vibrations have been seen in some atomic materials exhibiting an insulator-metal transition also referred to as metallization. We also find minima in the lattice vibrations and diffusion coefficient of small particles as a function of ns:nl, indicating enhanced stability of certain crystal structures for ns:nl values that form compounds. © 2021, CC BY.

关键词： Molecular dynamics