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Interpreting pulsar timing array data of gravitational waves with Ekpyrosis-bouncing cosmology

Physical Review D 2025年第4期111卷 043508-043508页

作者： Taotao Qiu Mian Zhu School of Physics Huazhong University of Science and Technology Wuhan 430074 China Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University 30-348 Krakow Poland

Recent pulsar timing array (PTA) experiments have reported strong evidence of the stochastic gravitational wave background (SGWB). If interpreted as primordial gravitational waves, the signal favors a strongly blue-tilted spectrum. On the other hand, the Ekpyrosis-bouncing cosmology with a strongly blue-tilted gravitational wave spectrum, i.e., nT≃2, offers a potential explanation for the observed SGWB signal. In this paper, we construct a concrete Ekpyrosis-bouncing model, and show its capacity to intepret the PTA result without pathologies. Both tensor and scalar perturbations are analyzed with constraints from the current observations.

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The Semiconfined Harmonic Oscillator with a Position-Dependent Effective Mass: Exact Solution, Dynamical Symmetry Algebra and Quasiprobability Distribution Functions

The Semiconfined Harmonic Oscillator with a Position-Depen...

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International Workshop on Lie Theory and Its Applications in physics, LT 2023

作者： Jafarov, E.I. Nagiyev, S.M. Van der Jeugt, J. Institute of Physics Ministry of Science and Education Javid av. 131 BakuAZ1143 Azerbaijan Department of Applied Mathematics Computer Science and Statistics Faculty of Sciences Ghent University Krijgslaan 281-S9 Gent9000 Belgium

ISBN: (纸本)9789819764525

We present some details of the new model of the quantum harmonic oscillator that is semiconfined due to a specific change of its mass by position. We succeeded in solving exactly the Schrödinger equation corresponding to this model. Moreover, we found its dynamical symmetry algebra and could compute analytically its Kirkwood, Husimi and Wigner joint quasiprobability functions. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： Schrodinger equation

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A system for detecting scratches on the surface of small-sized metal shafts after the grinding process using optical techniques combined with computer vision.

A system for detecting scratches on the surface of small-siz...

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International Symposium on applied science 2024, ISAS 2024

作者： Dau, Sy Hieu An, Khang Le Nguyen Thi, Phuc Dang Department of Applied Physics Applied Sciences Faculty Ho Chi Minh city University of Technology Vietnam National University HCMC Ho Chi Minh City Viet Nam Department of Computer Science Faculty of Information Technology Industrial University of Ho Chi Minh City Ho Chi Minh City Viet Nam

During the grinding process of metal machine parts requiring a high degree of smoothness, the use of diamond-surfaced grinding tools, specialized grinding stones, or high-hardness metals are common choices. However, during grinding, surface tool damage or misalignment between grinding surfaces can cause defects such as cracks, scratches, or complete surface destruction. Detecting small scratches is one of the biggest challenges due to their size and distribution, making it difficult to quickly identify them using the human eye. Automated systems, on the other hand, struggle to highlight scratches because automatic optical lighting systems face strong reflections from the metal surface, especially cylindrical surfaces after being polished. As a result, the images obtained lack controlled reflection positions and contrast between normal and scratched areas, leading to inefficiency in detecting these scratches. In this study, we propose an optical system combined with lighting techniques to highlight scratches on the surface of a cylindrical machine part after polishing, thereby detecting and classifying these defects to make pass-fail decisions in practical production line applications. © 2025 Institute of physics Publishing. All rights reserved.

关键词： Grinding (machining)

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Tunable and wideband high-performance rare earth-doped Ni-Mg-Cu-Zn nano ferrite-based meta-absorbers for C-band application

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Journal of Rare Earths 2025年第1期43卷 124-132,I0005页

作者： Majid Niaz Akhtar Magbool Alelyani Fatimah Mohammed AAlzahrani Abdullah Almohammedi Sabih Qamar MABaqir MIrfan Muhammad Azhar Khan Kheir SAlbarkaty ZAAlrowaili MSAl-Buriahi Institute of Physics The Islamia University of Bahawalpur63100BahawalpurPakistan Department of Radiological Sciences College of Applied Medical ScienceKing Khalid University61421bhaSaudi Arabia Department of Chemistry College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabi Department of Physics Faculty of ScienceIslamic University of Madinah42352.Saudi Arabia Department of Chemical Engineering Muhammad Nawaz Sharif University of Engineering and Technology(MNSUET)60000MultanPakistan Department of Electrical and Computer Engineering COMSATS University IslamabadSahiwal Campus57000Pakistan Department of Physics Umm Al-Qura UniversityMakkah24382Saudi Arabia Department of Physics College of ScienceJouf UniversityP.O.Box:201474331SakakaSoudi Arabia Department of Physics Sakarya University6900SakaryaTurkey

Due to advanced technology,electromagnet interference and dissipation problems in the electronic and portable devices at GHz range are increasing *** absorbing materials with outstanding electromagnetic properties,wide bandwidth,and strong absorption are highly *** present investigation deals with the preparation of Ni-Mg-Cu-Zn(NMCZ)substituted nano ferrites with composition of Ni_(0.3)Mg_(0.2)Cu_(0.3)Zn_(0.2)X_(0.02)Fe_(1.98)O_(4)(X=Nd,Ho,Pr,Gd,Yb).X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),a vibratory sample magnetometer(VSM),and a Vector network analyzer(VNA)were used to investigate these rare earth-doped nanocrystalline ferrites'*** reveals the single spinel phase structure in all Ni-Mg-Cu-Zn *** spectroscopy shows the presence of tetrahedral and octahedral bands of spinel *** images reveal the lowest agglomeration for the Ho-doped NMCZ nano-spinel ferrites *** images show the hexagon shapes of the Yb-and Nd-doped NMCZ ***-doped NMCZ ferrites show more coercivity than other rare earth metals substituted NMCZ nanocrystalline *** analysis was used to calculate the magnetic features like initial permeability,magnetic anisotropy constant,remanence,coercivity,and magnetic ***-frequency switching field distributions(SFD)analyses were also *** characteristics such as losses,permittivity,modulus,Q,ac conductivity,and impedance of the Nd^(-),Ho^(-),Pr^(-),Gd^(-),Yb-doped Ni-Mg-Cu-Zn ferrites were *** minimum reflection loss(-57.3 dB)is found at 1.4 GHz for Pr-doped Ni-Mg-Cu-Zn ferrite ***,the reflection loss(RL)of-53.9 dB at 2.9 GHz is observed for Ho-doped Ni-Mg-Cu-Zn ferrite *** magnetization,low coercivity,outstanding magnetodielectric,and absorption properties of theNd^(-),Ho^(-),Pr^(-),Gd^(-)and Yb^(-)doped Ni-Mg

关键词： Rare earths Reflection loss Cubic phase Magnetodielectric Ni-Mg-Cu-Zn(NMCZ)meta-absorber

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Polyp image segmentation based on improved planet optimization algorithm using reptile search algorithm

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Neural Computing and Applications 2025年第8期37卷 6327-6349页

作者： Abd Elaziz, Mohamed Al-qaness, Mohammed A. A. Al-Betar, Mohammed Azmi Ewees, Ahmed A. Department of Mathematics Faculty of Science Zagazig University Zagazig Egypt College of Physics and Electronic Information Engineering Zhejiang Normal University Jinhua321004 China Zhejiang Institute of Optoelectronics Jinhua321004 China Faculty of Computer Science and Engineering Galala University Suze435611 Egypt Ajman University Ajman346 United Arab Emirates College of Computing and Information Technology University of Bisha Bisha Saudi Arabia Department of Computer Damietta University Damietta Egypt Hourani Center for Applied Scientific Research Al-Ahliyya Amman University Amman Jordan

To recognize the potential for colon polyps to develop into cancer over time, early diagnosis is crucial for preventative healthcare. Timely identification significantly improves the prognosis and treatment outcomes for colorectal cancer patients. Image segmentation is crucial in medical image analysis for accurate diagnosis and treatment planning. Therefore, in this study, we present an alternative multilevel thresholding polyp segmentation method (MPOA) to enhance the segmentation of polyp images. The proposed method is based on enhancing the planet optimization algorithm (POA) by integrating operators from the reptile search algorithm (RSA). The evaluation of the developed MPOA is tested with different polyp images and compared with other image segmentation approaches. The results highlight the superior capability of MPOA, as evidenced by various performance measures in effectively segmenting polyp images. Furthermore, metrics such as peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and fitness values demonstrate that MPOA outperforms the basic version of POA and other methods. The evaluation outcomes underscore the significant impact of RSA in enhancing the performance of POA for the segmentation of polyp images. © The Author(s) 2025.

关键词： Diseases

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Enhancing the Swanepoel method: precise envelope detection of thin-film transmission spectra

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Optics Express 2025年第6期33卷 13376-13400页

作者： Ballester, Manuel Marquez, Almudena P. Lopez-Tapia, Santiago Fernandez, Susana Bass, John Minkov, Dorian Wuersch, Christoph Willomitzer, Florian Marquez, Emilio Katsaggelos, Aggelos K. Computer Science Department Northwestern University EvanstonIL60208 United States Department of Mathematics Faculty of Science University of Cadiz Puerto Real11510 Spain Department of Electrical and Computer Engineering Northwestern University EvanstonIL60208 United States CIEMAT Avenida Complutense 40 Madrid28040 Spain Wyant College of Optical Sciences University of Arizona TucsonAZ85721 United States Sofia1000 Bulgaria Institute for Computational Engineering ICE OST Eastern Switzerland University of Applied Sciences Switzerland Department of Condensed-matter Physics Faculty of Science University of Cadiz Puerto Real11510 Spain

The Swanepoel method is a widely used optical technique for characterizing thin films through normal-incidence transmission measurements. A critical step in this approach involves extracting the upper and lower envelopes of the measured oscillatory spectrum. By analyzing the transmission spectrum and its corresponding envelopes, the Swanepoel procedure enables precise determination of the film refractive index and extinction coefficient. However, even minor inaccuracies in envelope construction can propagate significant errors into the final characterization results. To address this challenge, we present what we believe to be a novel physics-informed optimization algorithm for envelope detection. Our mathematical model reformulates the envelope detection problem as a global optimization task that enforces the physical properties of the Swanepoel envelopes. Extensive validation on fifty randomly generated transmission spectra demonstrates unprecedented accuracy: the method achieves root-mean-square errors (RMSE) below 0.10% for the upper envelope and 0.06% for the lower envelope (more than doubling the accuracy of current state-of-the-art approaches). Furthermore, the proposed model has been assessed with two experimental transmission spectra, demonstrating its robustness and accuracy with real noisy data. We have developed an open-source Python software package (see text below). This software includes not only our innovative envelope construction algorithm but also additional envelope drawing algorithms for comparison and an efficient implementation of the Swanepoel method, enabling complete optical characterization of thin films. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Mean square error

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ODYSSEY OF THE ELUSIVE Θ+

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Acta Physica Polonica B 2025年第3-4期56卷

作者： Praszalowicz, Michal Institute of Theoretical Physics Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University S. Lojasiewicza 11 Kraków30-348 Poland

Θ+ is a putative light pentaquark state of positive parity with minimal quark content (uudds¯). It naturally emerges in chiral models for baryons, but experimental evidence is uncertain. We review the theoretical foundations of chiral models and their phenomenological applications to exotic states. In particular, we discuss in detail the pentaquark widths with special emphasis on the cancellations occurring in the decay operator. We also discuss some experiments, mainly those whose positive evidence of Θ+ persists to this day. This review is dedicated to Dmitry Diakonov, Victor Petrov, and Maxim Polyakov and their contribution to the Θ+ story. © 2025 Jagiellonian University. All rights reserved.

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Heat as a Witness of Quantum Properties

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Physical Review Letters 2025年第5期134卷 050401-050401页

作者： A. de Oliveira Junior Jonatan Bohr Brask Patryk Lipka-Bartosik Center for Macroscopic Quantum States bigQ Department of Physics Technical University of Denmark Fysikvej 307 2800 Kongens Lyngby Denmark Department of Applied Physics University of Geneva 1211 Geneva Switzerland Institute of Theoretical Physics Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University 30-348 Kraków Poland

We present a new approach for witnessing quantum resources, such as entanglement and coherence, based on heat generation. Inspired by Maxwell’s demon, we ask what the optimal heat exchange between a quantum system and a thermal environment is when the process is assisted by a quantum memory. We derive fundamental energy constraints in this scenario and show that quantum states can reveal nonclassical signatures via heat exchange. This approach leads to a heat-based witness for quantum properties, offering an alternative to system-specific measurements, as it only relies on fixed energy measurements in a thermal ancilla. We illustrate our findings with the detection of entanglement in isotropic states and coherence in two-spin systems interacting with a single-mode electromagnetic field.

关键词： Quantum entanglement

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Deep learning and ensemble methods for anomaly detection in ICS security

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International Journal of Information Technology (Singapore) 2025年第3期17卷 1761-1775页

作者： Hossain, Md. Alamgir Hasan, Tahmid Karovic, jr, Vincent Abdeljaber, Hikmat A. M. Haque, Md. Alimul Ahmad, Sultan Zafar, Aasim Nazeer, Jabeen Mishra, B.K. Department of Computer Science and Engineering State University of Bangladesh South Purbachal Kanchan Dhaka 1461 Bangladesh Department of Computer Science and Engineering Prime University Dhaka Bangladesh Department of Information Systems Faculty of Management Comenius Bratislava Odbojárov 10 Bratislava 25 82005 Slovakia Department of Computer Science Faculty of Information Technology Applied Science Private University Amman 11931 Jordan MEU Research Unit Middle East University Amman 11831 Lebanon Department of Computer Science Veer Kunwar Singh University Bihar Ara India Department of Computer Science College of Computer Engineering and Sciences Prince Sattam Bin Abdulaziz University Alkharj 11942 Saudi Arabia University Center for Research and Development (UCRD) Department of Computer Science and Engineering Chandigarh University Gharuan Punjab Mohali 140413 India Department of Computer Science Aligarh Muslim University U.P Aligarh 202002 India P.G. Department of Physics Veer Kunwar Singh University Bihar Ara India

This research addresses the escalating threats to industrial control systems by introducing a novel approach that combines deep learning for feature selection with a robust ensemble-based classification technique to enhance anomaly detection. Our method utilizes a tailored autoencoder architecture to efficiently select features, followed by a Random Forest classifier to ensure reliable and generalizable detection of anomalies. Evaluated on the HAI Security Dataset, the proposed approach demonstrates exceptional performance, with significant improvements in detecting anomalous activities in ICS. The results highlight the method’s potential to enhance ICS security by providing a scalable and adaptable framework that evolves with emerging threats. This study not only advances cybersecurity methodologies for industrial systems but also lays the groundwork for future research, emphasizing the need for innovative and effective security solutions in the face of evolving cyber challenges. © Bharati Vidyapeeth's Institute of computer Applications and Management 2024.

关键词： Anomaly detection in ICS Cyber-resilience in critical infrastructure Deep learning for feature selection Industrial control systems security Random forest classifier for ICS

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Fine structure of phase diagram for social impact theory

arXiv

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arXiv 2025年

作者： Malarz, Krzysztof Woloszyn, Maciej AGH University Faculty of Physics and Applied Computer Science al. Mickiewicza 30 Kraków30-059 Poland

In this paper, the social impact theory introduced by Latané is reconsidered. A fully differentiated society is considered;that is, initially every actor has their own opinion. The equivalent of Muller’s ratchet guards that—even for the non-deterministic case (with a positive social temperature)—any opinion once removed from the opinion space does not appear again. With computer simulation, we construct the phase diagram for Latané model based on the number of surviving opinions after various evolution times. The phase diagram is constructed on the two-dimensional plane of model control parameters responsible for the effective range of interaction among actors and the social temperature. Introducing the Muller’s ratchet-like mechanism gives a non-zero chance for any opinion to be removed from the system. We believe that in such a case, for any positive temperature, ultimately a consensus is reached. However, even for a moderate system size, the time to reach consensus is very long. In contrast, for the deterministic case (without social temperature), the system may be frozen with clusters of actors having several different opinions, or even reach the cycle limit (with blinking structures). Copyright © 2025, The Authors. All rights reserved.

关键词： Sociology

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