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Improvement of phase sensitivity in SU(1,1) interferometer via a Kerr nonlinear

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arXiv 2021年

作者： Chang, Shoukang Ye, Wei Zhang, Huan Hu, Liyun Hu Huang, Jiehui Liu, Sanqiu Center for Quantum Science and Technology Jiangxi Normal University Nanchang330022 China School of Mathematics Physics and Statistics Shanghai University of Engineering Science Shanghai201620 China Department of Physics Nanchang University 330031 China School of Computer Science and Engineering Central South University Changsha410083 China

We propose a theoretical scheme to enhance the phase sensitivity by introducing a Kerr nonlinear phase shift into the traditional SU(1,1) interferometer with a coherent state input and homodyne detection. We investigate the realistic effects of photon losses on phase sensitivity and quantum Fisher information. The results show that compared with the linear phase shift in SU(1,1) interferometer, the Kerr nonlinear case can not only enhance the phase sensitivity and quantum Fisher information, but also significantly suppress the photon losses. We also observe that at the same accessible parameters, internal losses have a greater influence on the phase sensitivity than the external ones. It is interesting that, our scheme shows an obvious advantage of low-cost input resources to obtain higher phase sensitivity and larger quantum Fisher information due to the introduction of nonlinear phase element. © 2021, CC BY.

关键词： Fisher information matrix

Quasi-Coordinate Search for a Randomly Moving Target

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Journal of Applied mathematics and Physics 2019年第8期7卷 1814-1825页

作者： A. A. M. Teamah W. A. Afifi Department of Mathematics Faculty of Science Tanta University Tanta Egypt Mathematics and Statistics Department College of Science Taibah University Yanbu KSA Mathematics and Statistics Department Canal Higher Institute of Engineering and Technology Suez Egypt

In this paper, we study the quasi-coordinated search technique for a lost target assumed to move randomly on one of two disjoint lines according to a random walk motion, where there are two searchers beginning their search from the origin on the first line and other two searchers begin their search from the origin on the second line. But the motion of the two searchers on the first line is independent from the motion of the other two searchers on the second line. Here we introduce a model of search plan and investigate the expected value of the first meeting time between one of the searchers and the lost target. Also, we prove the existence of a search plan which minimizes the expected value of the first meeting time between one of the searchers and the target.

关键词： Random Walker Linear Search Expected Value Optimal Search Plane Stochastic Process

HILBERT FUNCTIONS AND JORDAN TYPE OF PERAZZO ARTINIAN ALGEBRAS

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arXiv 2023年

作者： Abdallah, Nancy Altafi, Nasrin de Poi, Pietro Fiorindo, Luca Iarrobino, Anthony Marques, Pedro Macias Mezzetti, Emilia Miró-Roig, Rosa M. Nicklasson, Lisa Department of Engineering Borås University Sweden Department of Mathematics and Statistics Queen’s University KingstonON Canada Department of Mathematics KTH Royal Institute of Technology Sweden Dipartimento di Scienze Matematiche Informatiche e Fisiche Università degli Studi di Udine Via delle Scienze 206 Udine33100 Italy Dipartimento di Matematica Università di Genova Via Dodecaneso 35 Genova16146 Italy Department of Mathematics Northeastern University BostonMA02115 United States Departamento de Matemática Escola de Ciências e Tecnologia Centro de Investigação em Matemática e Aplicações Instituto de Investigação e Formação Avançada Universidade de Évora Rua Romão Ramalho 59 ÉvoraP–7000–671 Portugal Dipartimento di Matematica e Geoscienze Università di Trieste Via Valerio 12/1 Trieste34127 Italy Facultat de Matemàtiques i Informàtica Universitat de Barcelona Gran Via des les Corts Catalanes 585 Barcelona08007 Spain

We study Hilbert functions, Lefschetz properties, and Jordan type of Artinian Gorenstein algebras associated to Perazzo hypersurfaces in projective space. The main focus lies on Perazzo threefolds, for which we prove that the Hilbert functions are always unimodal. Further we prove that the Hilbert function determines whether the algebra is weak Lefschetz, and we characterize those Hilbert functions for which the weak Lefschetz property holds. By example, we verify that the Hilbert functions of Perazzo fourfolds are not always unimodal. In the particular case of Perazzo threefolds with the smallest possible Hilbert function, we give a description of the possible Jordan types for multiplication by any linear *** Codes 13E10 (primary), 13D40, 14M05, 13H10 © 2023, CC BY-NC-ND.

关键词： Algebra

Preparation of a New Hybrid Mgalldh@Magnetite Activated Charcoal by Hydrothermal Method for Stability and Adsorption Mechanism of Congo Red

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SSRN

SSRN 2024年

作者： Ahmad, Nur Kameda, Tomohito Rahman, Mir Tamzid Rahman, Farzana Lesbani, Aldes Graduate School of Mathematics and Natural Science FMIPA Universitas Sriwijaya Sumatera Selatan Palembang30139 Indonesia Research Center of Inorganic Materials and Complexes Universitas Sriwijaya Sumatera Selatan Palembang30139 Indonesia Graduate School of Environmental Studies Tohoku University 6-6-20 Aoba Aramaki Aobaku Sendai980-8579 Japan Department of Chemistry Jahangirnagar University Dhaka Savar1342 Bangladesh Department of Nutrition and Food Engineering Daffodil International University Birulia1216 Bangladesh Master Program of Material Science Graduate School of Universitas Sriwijaya Sumatera Selatan Palembang30139 Indonesia

Background The removal of hazardous dyes from water by magnetic adsorbents has received significant interest due to their low cost and ease of separation from the solution phase. This study explores the efficacy of a novel hybrid adsorbent, magnetite and activated charcoal-modified MgAl layered double hydroxide (MgAlLDH@MAC), for removing congo red (CR) from aqueous solutions. Methods MgAlLDH@MAC was successfully prepared via a co-precipitation to hydrothermal method and characterized using FE-SEM, FE-STEM, VSM, BET, XRD, FTIR, XPS, and HPLC analysis. Significant findings The incorporation of magnetite and activated charcoal was successful, resulting in excellent adsorption performance for CR and easy separation from the solution due to its magnetic properties. The adsorbent achieved a maximum adsorption capacity of 625 mg/g, which is in line with the Langmuir isotherm and pseudo-second-order kinetic model. Moreover, the adsorbent demonstrated excellent stability and reusability, retaining 91.78% efficiency after five adsorption-desorption. This study offers a fresh viewpoint on creating high-performance LDH adsorbents that remove dyes quickly and effectively using carbon and magnetite materials. © 2024, The Authors. All rights reserved.

关键词： Magnetite

New extremal binary self-dual codes of length 68 from a novel approach to neighbors

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arXiv 2020年

作者： Gildea, Joe Kaya, Abidin Korban, Adrian Yildiz, Bahattin Department of Mathematical and Physical Sciences Faculty of Science and Engineering University of Chester England United Kingdom Department of Mathematics Education Sampoerna University Jakarta12780 Indonesia Department of Mathematics & Statistics Northern Arizona University FlagstaffAZ86001 United States

In this work, we introduce the concept of distance between self-dual codes, which generalizes the concept of a neighbor for self-dual codes. Using the k-neighbors, we are able to construct extremal binary self-dual codes of length 68 with new weight enumerators. We construct 143 extremal binary self-dual codes of length 68 with new weight enumerators including 42 codes with γ = 8 in their W68,2 and 40 with γ = 9 in their W68,2. These examples are the first in the literature for these γ values. This completes the theoretical list of possible values for γ in W68,*** codes 94B05 Copyright © 2020, The Authors. All rights reserved.

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Machine learning applications for COVID-19: A state-of-the-art review

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arXiv 2021年

作者： Kamalov, Firuz Cherukuri, Aswani Sulieman, Hana Thabtah, Fadi Hossain, Akbar Department of Electrical Engineering Canadian University Dubai Dubai United Arab Emirates School of IT and Engineering Vellore Institute of Technology Vellore India Department of Mathematics and Statistics American University of Sharjah Sharjah United Arab Emirates School of Digital Technologies Manukau Institute of Technology Auckland New Zealand School of Engineering Auckland University of Technology Auckland New Zealand

The COVID-19 pandemic has galvanized the machine learning community to create new solutions that can help in the fight against the virus. The body of literature related to applications of machine learning and artificial intelligence to COVID-19 is constantly growing. The goal of this article is to present the latest advances in machine learning research applied to COVID-19. We cover four major areas of research: forecasting, medical diagnostics, drug development, and contact tracing. We review and analyze the most successful state of the art studies. In contrast to other existing surveys on the subject, our article presents a high level overview of the current research that is sufficiently detailed to provide an informed insight. Copyright © 2021, The Authors. All rights reserved.

关键词： Viruses

REPEAT ANALYSIS program AS A QUALITY ASSURANCE SYSTEM FOR RADIOLOGY MANAGEMENT: CAUSAL REPEAT AND AN OVERVIEW

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Journal of Medical Imaging and Radiation Sciences 2023年第3期54卷 S31-S31页

作者： Rochmayanti, Dwi Adi, Kusworo Widodo, Catur Edi Doctoral Program of Information System School of Postgraduate Diponegoro University Department of Radiodiagnostic and Radiotherapy Engineering Health Polytechnic Ministry of Health Semarang Central Java Department of Physics Faculty of Science and Mathematics Diponegoro University

OBJECTIVEThis paper aims to describe the image retakes program over several decades, and identify the causes of issues due to rejection rates. MATERIALS & METHODSThis study is a literature review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. Articles were searched from Google Scholar (3140) and Scopus (18) using keywords " Reject" or " Repeat" or " Retakes" and " Analysis" and " in" and " Diagnostic" and " Imaging". The article range was expanded to describe the profile of repeat analysis from the use of film-screen to digital transformation systems. Based on the established criteria, 20 articles were extracted and analyzed. RESULTSFrom the literature, it was found that repeat rates above 5% were still found in some examination categories, with chest radiography contributing the highest rejection rate, reaching 51.67%, with the biggest contributing factor being positioning (84.8%). There are interesting findings related to this program, where subjective factors in determining the classification of rejection causes still exist. One study mentioned that AI can predict image rejection accuracy with a sensitivity of 93%. Therefore, the use of AI can be very helpful in classifying rejection causes, making data available for more efficient and easier radiology management. CONCLUSIONRepeat program is part of image quality management. The justification for rejection decisions still poses a challenge related to personnel's subjective factors and determining the causes of rejection/repeat must also be done to obtain concrete data related to radiography performance.

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Effects of concurrency on epidemic spreading in Markovian temporal networks

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arXiv 2022年

作者： Liu, Ruodan Ogura, Masaki Reis, Elohim Fonseca Dos Masuda, Naoki Department of Mathematics State University of New York at Buffalo BuffaloNY14260-2900 United States Graduate School of Information Science and Technology Osaka University Osaka Suita565-0871 Japan Computational and Data-Enabled Sciences and Engineering Program State University of New York at Buffalo BuffaloNY14260-5030 United States Faculty of Science and Engineering Waseda University Tokyo169-8555 Japan

The concurrency of edges, quantified by the number of edges that share a common node at a given time point, may be an important determinant of epidemic processes in temporal networks. We propose theoretically tractable Markovian temporal network models in which each edge flips between the active and inactive states in continuous time. The different models have different amounts of concurrency while we can tune the models to share the same statistics of edge activation and deactivation (and hence the fraction of time for which each edge is active) and the structure of the aggregate (i.e., static) network. We analytically calculate the amount of concurrency of edges sharing a node for each model. We then numerically study effects of concurrency on epidemic spreading in the stochastic susceptible-infectious-susceptible and susceptible-infectious-recovered dynamics on the proposed temporal network models. We find that the concurrency enhances epidemic spreading near the epidemic threshold while this effect is small in many cases. Furthermore, when the infection rate is substantially larger than the epidemic threshold, the concurrency suppresses epidemic spreading in a majority of cases. In sum, our numerical simulations suggest that the impact of concurrency on enhancing epidemic spreading within our model is consistently present near the epidemic threshold but modest. The proposed temporal network models are expected to be useful for investigating effects of concurrency on various collective dynamics on networks including both infectious and other dynamics. Copyright © 2022, The Authors. All rights reserved.

关键词： Dynamics

Spontaneously generated flux ropes in 3-D magnetic reconnection

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arXiv 2024年

作者： Bai, Shi-Chen Guo, Ruilong Xiao, Yuchen Shi, Quanqi Yao, Zhonghua Pu, Zuyin Sun, Wei-Jie Degeling, Alexander W. Tian, Anmin Rae, I. Jonathan Yao, Shutao Zong, Qiu-Gang Fu, Suiyan Bu, Yude Russell, Christopher T. Burch, James L. Gershman, Daniel J. School of Mathematics and Statistics Shandong University Weihai Shandong264209 China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai264209 China Weihai Institute for Interdisciplinary Research Shandong University Weihai Shandong264209 China Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing100029 China School of Earth and Space Sciences Peking University Beijing100871 China Space Sciences Laboratory University of California BerkeleyCA94720 United States Department of Mathematics Physics and Electrical Engineering Northumbria University Newcastle United Kingdom Department of Earth Planetary and Space Sciences Institute of Geophysics and Planetary Physics University of California Los AngelesCA90095 United States Southwest Research Institute San AntonioTX78238 United States NASA Goddard Space Flight Center GreenbeltMD20771 United States

Magnetic reconnection is the key to explosive phenomena in the universe. The flux rope is crucial in three-dimensional magnetic reconnection theory and are commonly considered to be generated by secondary tearing mode instability. Here we show that the parallel electron flow moving toward the reconnection diffusion region can spontaneously form flux ropes. The electron flows form parallel current tubes in the separatrix region where the observational parameters suggest the tearing and Kelvin-Helmholtz instabilities are suppressed. The spontaneously formed flux ropes could indicate the importance of electron dynamics in a three-dimensional reconnection region. © 2024, CC BY.

关键词： Rope