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Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： S R wu B q Wang Z W Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the Reissner-Nordström-de Sitter BH surrounded by quintessence(RN-dSq).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dSq under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dSq are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant

Network Embedding Algorithm for Vulnerability Assessment of Power Transmission Lines Using Integrated Structure and Attribute Information

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 351-360页

作者： Xianglong Lian Tong qian Zepeng Li Xingyu Chen Wenhu Tang q.H.wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

In power systems,failures of vulnerable lines can trigger large-scale cascading failures,and vulnerability assessment is dedicated to locating these lines and reducing the risks of such *** on a structure and attribute network embedding(SANE)algorithm,a novel quantitative vulnerability analysis method is proposed to identify vulnerable lines in this ***,a two-layered random walk network with topological and electrical properties of transmission lines is ***,based on the weighted degree of nodes in the two-layered network,the inter-layer and intra-layer walking transition probabilities are developed to obtain walk ***,a Word2Vec algorithm is applied to obtain lowdimension vectors representing transmission lines,according to obtained walk sequences for calculating the vulnerability index of transmissions ***,the proposed method is compared with three widely used methods in two test *** show the network embedding based method is superior to those comparison methods and can provide guidance for identifying vulnerable lines.

关键词： Network embedding random walk transmission lines vulnerability assessment

Cardiovascular abnormalities of long-COVID syndrome:Pathogenic basis and potential strategy for treatment and rehabilitation

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Sports medicine and Health Science 2024年第3期6卷 221-231页

作者： Kainuo wu jonathan Van Name Lei Xi Virginia Commonwealth University School of medicine(m.D.Class 2024) RichmondVA23298USA Pauley Heart Center Division of CardiologyDepartment of Internal MedicineVirginia Commonwealth UniversityRichmondVA23298-0204USA

Cardiac injury and sustained cardiovascular abnormalities in long-COVID syndrome,***-acute sequelae of coronavirus disease 2019(COVID-19)have emerged as a debilitating health burden that has posed challenges for management of pre-existing cardiovascular conditions and other associated chronic comorbidities in the most vulnerable group of patients recovered from acute COVID-19.A clear and evidence-based guideline for treating cardiac issues of long-COVID syndrome is still *** this review,we have summarized the common cardiac symptoms reported in the months after acute COVID-19 illness and further evaluated the possible pathogenic factors underlying the pathophysiology process of *** mechanistic understanding of how Severe Acute Respiratory Syndrome Coronavirus 2(SARS-CoV-2)damages the heart and vasculatures is critical in developing targeted therapy and preventive measures for limiting the viral *** the currently available therapeutic interventions,a considerable portion of patients recovered from severe COVID-19 have reported a reduced functional reserve due to ***,a rigorous and comprehensive cardiac rehabilitation program with individualized exercise protocols would be instrumental for the patients with long-COVID to regain the physicalﬁtness levels comparable to their pre-illness baseline.

关键词： Long-COVID syndrome Cardiac rehabilitation Exercise intolerance Inﬂammation Hypoxia inducible factor 1 SARS-CoV-2 tropism

myocarditis–A silent killer in athletes:Comparative analysis on the evidence before and after COVID-19 pandemic

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Sports medicine and Health Science 2024年第3期6卷 232-239页

作者： jonathan Van Name Kainuo wu Lei Xi Virginia Commonwealth University School of medicine(m.D.Class 2024) RichmondVA23298USA Pauley Heart Center Division of CardiologyDepartment of Internal MedicineVirginia Commonwealth UniversityRichmondVA23298-0204USA

myocarditis is a rare cardiomyocyte inﬂammatory process,typically caused by viruses,with potentially devastating cardiac sequalae in both competitive athletes and in the general *** into myocarditis prevalence in the Coronavirus disease 2019(COVID-19)era suggests that infection with Severe acute respiratory syndrome coronavirus(SARS-CoV-2)is an independent risk factor for myocarditis,which is conﬁrmed mainly through cardiovascular magnetic resonance *** studies indicated that athletes have a decreased risk of myocarditis after recent COVID-19 infection compared to the general ***,given the unique nature of competitive athletics with their frequent participation in high-intensity exercise,athletes possess distinct factors of susceptibility for the development of myocarditis and its subsequent severe cardiac complications(e.g.,sudden cardiac death,fulminant heart failure,etc.).Under this context,this review focuses on comparing myocarditis in athletes versus non-athletes,owing special attention to the distinct clinical presentations and outcomes of myocarditis caused by different viral pathogens such as cytomegalovirus,Epstein-Barr virus,human herpesvirus-6,human immunodeﬁciency virus,and Parvovirus B19,both before and after the COVID-19 pandemic,as compared with *** illustrating distinct clinical presentations and outcomes of myocarditis in athletes versus non-athletes,we also highlight the critical importance of early detection,vigilant monitoring,and effective management of viral and non-viral myocarditis in athletes and the necessity for further optimization of the return-to-play guidelines for athletes in the COVID-19 era,in order to minimize the risks for the rare but devastating cardiac fatality.

关键词： COVID-19 myocarditis Cardiovascular symptomatology Athlete susceptibility Return-to-play Sudden cardiac death Viral pathogens High-intensity exercise

Sequential fusion estimation for multisensor systems with non-Gaussian noises

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Science China(Information Sciences) 2020年第12期63卷 153-165页

作者： Liping YAN Chenying DI q.m.jonathan wu Yuanqing XIA Key Laboratory of Intelligent Control and Decision of Complex Systems School of AutomationBeijing Institute of Technology Department of Electrical and Computer Engineering University of Windsor

The sequential fusion estimation for multisensor systems disturbed by non-Gaussian but heavytailed noises is studied in this paper. Based on multivariate t-distribution and the approximate t-filter,the sequential fusion algorithm is presented. The performance of the proposed algorithm is analyzed and compared with the t-filter-based centralized batch fusion and the Gaussian Kalman filter-based optimal centralized fusion. Theoretical analysis and exhaustive experimental analysis show that the proposed algorithm is effective. As the generalization of the classical Gaussian Kalman filter-based optimal sequential fusion algorithm, the presented algorithm is shown to be superior to the Gaussian Kalman filter-based optimal centralized batch fusion and the optimal sequential fusion in estimation of dynamic systems with non-Gaussian noises.

关键词： state estimation sequential fusion non-Gaussian disturbance heavy-tailed noise multivariate $t$-distribution

A Fractal Dimension Based Framework for Night Vision Fusion

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 220-227页

作者： Gaurav Bhatnagar q.m.jonathan wu IEEE the Department of mathematics Indian Institute of Technology Jodhpur the Department of Electrical and Computer Engineering University of Windsor

In this paper, a novel fusion framework is proposed for night-vision applications such as pedestrian recognition,vehicle navigation and surveillance. The underlying concept is to combine low-light visible and infrared imagery into a single output to enhance visual perception. The proposed framework is computationally simple since it is only realized in the spatial domain. The core idea is to obtain an initial fused image by averaging all the source images. The initial fused image is then enhanced by selecting the most salient features guided from the root mean square error(RmSE) and fractal dimension of the visual and infrared images to obtain the final fused *** experiments on different scene imaginary demonstrate that it is consistently superior to the conventional image fusion methods in terms of visual and quantitative evaluations.

关键词： Fractal dimension image fusion navigation and surveillance night vision

Fingerprint Liveness Detection from Different Fingerprint materials Using Convolutional Neural Network and Principal Component Analysis

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Computers, materials & Continua 2017年第4期53卷 357-372页

作者： Chengsheng Yuan Xinting Li q.m.jonathan wu Jin Li Xingming Sun School of Computer and Software Nanjing University of Information Science&TechnologyNing Liu RoadNo.219NanjingChina210044 Jiangsu Engineering Center of Network monitoring Ning Liu RoadNo.219NanjingChina210044 Department of Electrical and Computer Engineering University of Windsor401 Sunset AvenueWindsorONCanada N9B 3P4 School of Computer Science Guangzhou UniversityYudongxi Road 36Tianhe DistrictGuangzhouChina510500

Fingerprint-spoofing attack often occurs when imposters gain access illegally by using artificial fingerprints,which are made of common fingerprint materials,such as silicon,latex,***,to protect our privacy,many fingerprint liveness detection methods are put forward to discriminate fake or true *** work on liveness detection for fingerprint images is focused on the construction of complex handcrafted features,but these methods normally destroy or lose spatial information between *** from existing methods,convolutional neural network(CNN)can generate high-level semantic representations by learning and concatenating low-level edge and shape features from a large amount of labeled ***,CNN is explored to solve the above problem and discriminate true fingerprints from fake ones in this *** reduce the redundant information and extract the most distinct features,ROI and PCA operations are performed for learned features of convolutional layer or pooling *** that,the extracted features are fed into SVm *** results based on the LivDet(2013)and the LivDet(2011)datasets,which are captured by using different fingerprint materials,indicate that the classification performance of our proposed method is both efficient and convenient compared with the other previous methods.

关键词： Fingerprint liveness detection CNNs PCA SVm ROI LivDet 2013 LivDet 2011

An immune-swarm intelligence based algorithm for deterministic coverage problems of wireless sensor networks

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Journal of Central South University 2012年第11期19卷 3154-3161页

作者：刘继忠王保磊敖俊宇 q.m.jonathan wu Institute of Robotics Nanchang University Department of Electrical and Computer Engineering University of Windsor

A novel immune-swarm intelligence (ISI) based algorithm for solving the deterministic coverage problems of wireless sensor networks was *** makes full use of information sharing and retains diversity from the principle of particle swarm optimization (PSO) and artificial immune system (AIS).The algorithm was analyzed in detail and proper swarm size,evolving generations,gene-exchange individual order,and gene-exchange proportion in molecule were obtained for better algorithm *** to the test results,the appropriate parameters are about 50 swarm individuals,over 3 000 evolving generations,20%-25% gene-exchange proportion in molecule with gene-exchange taking place between better fitness affinity *** algorithm is practical and effective in maximizing the coverage probability with given number of sensors and minimizing sensor numbers with required coverage probability in sensor *** can reach a better result quickly,especially with the proper calculation parameters.

关键词： wireless sensor network deterministic area coverage immune-swarm algorithm particle swarm optimization artificialimmune system

Evaluation of Well Spacing for Primary Development of Fractured Horizontal Wells in Tight Sandstone Gas Reservoirs

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Fluid Dynamics & materials Processing 2024年第5期20卷 1015-1030页

作者： Fang Li Juan wu Haiyong Yi Lihong wu Lingyun Du Yuan Zeng Exploration and Development Research Institute PetroChina Southwest Oil&Gas Field CompanyChengdu610041China Oil and Gas Resources Department PetroChina Southwest Oil&Gas Field CompanyChengdu610000China

methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors,such as strong reservoir heterogeneity and seepage *** this study,the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage *** the basis of these experiments,a numerical simulation model(based on the special seepage mechanism)and an inverse dynamic reserve algorithm(with different equivalent drainage areas)were *** well spacing ranges of Classes I,II,and III wells in the q gas field are determined to be 802–1,000,600–662,and 285–400 m,respectively,with their average ranges as 901,631,and 342.5 m,*** considering both the pairs of parallel well groups and series well groups as examples,the reliability of the calculation results is *** is shown that the combination of the two models can reduce errors and provide accurate results.

关键词： Well spacing for primary development tight gas reservoir fractured horizontal well threshold pressure gradient stress sensitivity