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Quasi-normal modes,emission rate,and shadow of charged AdS black holes with perfect fluid dark matter

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Chinese Physics C 2024年第8期48卷 246-256页

作者： Hao Chen Shi-Hai Dong Sepehr hassanabadi Narges Heidari hassan hassanabadi School of Physics and Electronic Science Zunyi Normal UniversityZunyi 563006China Research Center for Quantum Physics Huzhou UniversityHuzhou 313000China Centro de Investigación en Computación Instituto Politécnico NacionalUPALMMexico City 07700Mexico Department of Physics University of TehranNorth Karegar AvenueTehran 14395-547Iran Faculty of Physics Shahrood University of TechnologyShahroodIran Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

In this study,we comprehensively investigated charged AdS black holes surrounded by a distinct form of dark *** particular,we focused on key elements including the Hawking temperature,quasi-normal modes(QNMs),emission rate,and *** first calculated the Hawking temperature,thereby identifying critical values such as the critical radius and maximum temperature of the black hole,essential for determining its phase *** analysis focused on the QNMs of charged AdS black holes immersed in perfect fluid dark matter(PFDM)within the massless scalar field *** the Wentzel-Kramers-Brillouin(WKB)method,we accurately derived the frequencies of these ***,we conducted a meticulous assessment of how the intensity of the PFDM parameterαinfluences the partial absorption cross sections of the black hole,along with a detailed study of the frequency variation of the energy emission *** pivotal role of geodesics in understanding astrophysical black hole characteristics is ***,we examined the influence of the dark matter parameter on photon evolution by computing the shadow radius of the black *** findings distinctly demonstrate the significant impact of the PFDM parameterαon the boundaries of this shadow,providing crucial insights into its features and *** also provide profound insights into the intricate dynamics between a charged AdS black hole,novel dark matter,and various physical phenomena,elucidating their interplay and contributing valuable knowledge to the understanding of these cosmic entities.

关键词： black hole dark matter quasi-normal modes greybody factor shadow radius

Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad F.Zueter mohammad Zolfagharroshan Navid Bahrani Agus P.Sasmito Department of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada Department of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current practice of underground artificial ground freezing(AGF)typically involves huge refrigeration systems of large economic and environmental *** this study,a novel AGF technique is proposed deploying available cold wind in cold *** is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study provides mining practitioners with sustainable solutions of underground AGF.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions

Temperature-jump tensile tests to induce optimized TRIP/TWIP effect in a metastable austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2025-2036页

作者： mohammad Javad Sohrabi Hamed Mirzadeh Saeed Sadeghpour Abdol Reza Geranmayeh Reza Mahmudi School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran14395-515TehranIran Centre for Advanced Steels Research Materials and Mechanical EngineeringUniversity of Oulu90014 OuluFinland

In the present work,plastic deformation mechanisms were initially tailored by adjusting the deformation temperature in the range of 0 to 200℃ in AISI 304L austenitic stainless steel,aiming to optimize the strength-ductility *** was shown that the combined twinning-induced plasticity(TWIP)/transformation-induced plasticity(TRIP)effects and a wider strain range for the TRIP effect up to higher strains by adjusting the deformation temperature are good strategies to improve the strength-ductility synergy of this metastable stainless *** this regard,by consideration of the observed temperature-dependency of plastic deformation,the controlled sequence of TWIP and TRIP effects for archiving superior strength-ductility trade-off was intended by the pre-designed temperature jump tensile ***,the optimum tensile toughness of 846 MJ/m^(3) and total elongation to 133% were obtained by this strategy via exploiting the advantages of the TWIP effect at 100℃ and the TRIP effect at 25℃ at the later stages of the ***,a deformation-temperature-transformation(DTT)diagram was developed for this metastable ***,based on work-hardening analysis,it was found that the main phenomenon constraining further improvement in the ductility and strengthening was the yielding of the deformation-induced α′-martensite.

关键词： metastable stainless steels transformation-induced plasticity twinning-induced plasticity stacking fault energy mechanical properties

Towards a lightweight security framework using blockchain and machine learning

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Blockchain(Research and Applications) 2024年第1期5卷 107-118页

作者： Shereen Ismail Muhammad Nouman Diana W.Dawoud hassan Reza School of Electrical Engineering and Computer Science University of North DakotaND 58202USA Department of Computer Science COMSATS University IslamabadIslamabad 44000Pakistan College of Engineering and Information Technology University of DubaiDubaiUnited Arab Emirates

Cyber-attacks pose a significant challenge to the security of Internet of Things(IoT)sensor networks,necessitating the development of robust countermeasures tailored to their unique characteristics and *** prevention and detection techniques have been proposed to mitigate these *** this paper,we propose an integrated security framework using blockchain and Machine Learning(ML)to protect IoT sensor *** framework consists of two modules:a blockchain prevention module and an ML detection *** blockchain prevention module has two lightweight mechanisms:identity management and trust *** management employs a lightweight Smart Contract(SC)to manage node registration and authentication,ensuring that unauthorized entities are prohibited from engaging in any tasks,while trust management uses a lightweight SC that is responsible for maintaining trust and credibility between sensor nodes throughout the network’s lifetime and tracking historical node *** and transaction validation are achieved through a Verifiable Byzantine Fault Tolerance(VBFT)mechanism to ensure network reliability and *** ML detection module utilizes the Light Gradient Boosting Machine(LightGBM)algorithm to classify malicious nodes and notify the blockchain network if it must make decisions to mitigate their *** investigate the performance of several off-the-shelf ML algorithms,including Logistic Regression,Complement Naive Bayes,Nearest Centroid,and Stacking,using the WSN-DS *** is selected following a detailed comparative analysis conducted using accuracy,precision,recall,F1-score,processing time,training time,prediction time,computational complexity,and Matthews Correlation Coefficient(MCC)evaluation metrics.

关键词： Blockchain Machine learning IoT Security Integration Smart contracts

Using X Social Networks (formerly Twitter) and web news mining to predict the measles outbreak

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Asian Pacific Journal of Tropical Medicine 2024年第4期17卷 188-190页

作者： Kia Jahanbin mohammad Jokar Vahid Rahmanian Department of Computer Engineering Yazd University YazdIran Faculty of Veterinary Medicine Karaj BranchIslamic Azad UniversityKarajIran Department of Public Health Torbat Jam Faculty of Medical SciencesTorbat JamIran

Measles,an infectious disease caused by the measles virus,remains a significant public health concern worldwide due to its highly contagious nature and potential for severe complications[1].In addition to symptoms such as high fever,cough,Koplik spots,and rash,measles can lead to serious complications including pneumonia and myocarditis,particularly in vulnerable populations such as young children[1,2].

关键词： Twitter web mining

Decision Making Based on Valued Fuzzy Superhypergraphs

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1907-1923页

作者： mohammad Hamidi Florentin Smarandache Mohadeseh Taghinezhad Department of Mathematics University of Payame NoorTehran19395-4697Iran Department of Mathematics University of New MexicoGallup87301 NMUSA

This paper explores the defects in fuzzy (hyper) graphs (as complex (hyper) networks) and extends the fuzzy(hyper) graphs to fuzzy (quasi) superhypergraphs as a new *** have modeled the fuzzy superhypergraphsas complex superhypernetworks in order to make a relation between labeled objects in the form of details andgeneralities. Indeed, the structure of fuzzy (quasi) superhypergraphs collects groups of labeled objects and analyzesthem in the form of the part to part of objects, the part of objects to the whole group of objects, and the whole tothe whole group of objects at the same *** have investigated the properties of fuzzy (quasi) superhypergraphsbased on any positive real number as valued fuzzy (quasi) superhypergraphs, considering the complement of valuedfuzzy (quasi) superhypergraphs, the notation of isomorphism of valued fuzzy (quasi) superhypergraphs based onthe permutations, and we have presented the isomorphic conditions of (self complemented) valued fuzzy (quasi)superhypergraphs. The concept of impact membership value of fuzzy (quasi) superhypergraphs is introducedin this study and it is applied in designing the real problem in the real world. Finally, the problem of businesssuperhypernetworks is presented as an application of fuzzy valued quasi superhypergraphs in the real world.

关键词： (Quasi)superhypergraph valued fuzzy(quasi)superhypergraph impact membership value complex superhypernetwork

Role of renewable,non-renewable energy consumption and carbon emission in energy efficiency and productivity change:Evidence from G20 economies

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Geoscience Frontiers 2024年第4期15卷 474-493页

作者： Wasi Ul hassan Shah Gang Hao Hong Yan Nan Zhu Rizwana Yasmeen Gheorghi Dinca˘f a School of Management Zhejiang Shuren UniversityHangzhou 310015China Department of Management Sciences City University of Hong KongHong KongChina School of Management Zhejiang Shuren UniversityHangzhou 310015China The Western Business School Southwestern University of Finance and EconomicsChengduChina School of Economics and Management Panzhihua UniversityPanzhihua 617000SichuanChina Department of Finance and Accounting Transilvania University of BrașovBrașovRomania

The challenge of achieving sustainable economic development with a secure environmental system is a global challenge faced by both developed and developing *** Efficiency(EE)is crucial in achieving sustainable economic growth while reducing ecological *** research utilizes the Slack-Based Measure Data Envelopment Analysis(SBM-DEA)and the Malmquist-Luenberger Index(MLI)method to evaluate EE and productivity changes from 1995 to 2020 across G20 *** study uses four different input-output bundles to gauge the impact of renewable and non-renewable energy consumption and carbon emissions on EE and productivity *** study results show that including renewable energy consumption improves the average EE from 0.783 to 0.8578,but energy productivity declines from 1.0064 to *** bad output(carbon emissions)in the estimation process enhances renewable EE and productivity change,resulting in an average EE of 0.6678 and MLI of *** change is identified as the primary determinant of energy productivity growth in scenarios 1 and 2,while technical efficiency determines energy productivity change in scenarios 3 and *** Kruskal-Wallis test reveals a significant statistical difference between the mean EE and MLI scores of G20 countries.

关键词： Renewable energy DEA Energy Efficiency Productivity change Carbon emissions

Correction‐enabled reversible data hiding with pixel repetition for high embedding rate and quality preservation

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IET Cyber-Systems and Robotics 2024年第3期6卷 49-61页

作者： mohammad Ali Kawser Hussain Nyeem Md Abdul Wahed School of Transportation Science and Engineering Beihang UniversityBeijingChina Department of Electrical Electronic and Communication Engineering(EECE)Military Institute of Science and Technology(MIST)DhakaBangladesh

A novel correction‐enabled Pixel Repetition(PR)‐based Reversible Data Hiding(RDH)framework,featuring a new embedding scheme is *** proposed RDH scheme uses contextually redundant block pixels,generated via PR,in a two‐phase adaptive embedding process,enhancing both image quality and data embedding ***,each 2×2 block encodes 4 bits of data using new mapping conditions that facilitate seed pixel reconstruction from remaining block pixels and provide additional embedding ***,an innovative post‐embedding error correction technique,based on 2^(k)‐bit error‐correction,minimises post‐embedding distortion,further improving image *** error correction approach augments data embedding robustness,vital for applications like medical imaging,telemedicine,and digital watermarking that requires high embedding capacity with minimum possible *** proposed scheme surpasses existing state‐of‐the‐art methods in embedding ratedistortion performance,validated through subjective and objective ***,statistical analysis,including histogram and fragility testing,confirms the scheme's potential for image authentication across diverse multimedia *** correctionenabled RDH with PR offers enhanced embedding capacity and image quality preservation,making it particularly advantageous for applications requiring robust data hiding while maintaining visual fidelity.

关键词： data assimilation vision

A Review of Privacy and Security of Edge Computing in Smart Healthcare Systems: Issues, Challenges, and Research Directions

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Tsinghua Science and Technology 2024年第4期29卷 1152-1180页

作者： Ahmad Alzu’bi Ala’a Alomar Shahed Alkhaza’leh Abdelrahman Abuarqoub mohammad Hammoudeh Department of Computer Science Jordan University of Science and TechnologyIrbid 22110Jordan Cardiff School of Technologies Cardiff Metropolitan UniversityCardiff CF52YBUK Department of Information and Computer Science King Fahd University of Petroleum and MineralsDhahran 31261Kingdom of Saudi Arabia

The healthcare industry is rapidly adapting to new computing environments and technologies. With academics increasingly committed to developing and enhancing healthcare solutions that combine the Internet of Things (IoT) and edge computing, there is a greater need than ever to adequately monitor the data being acquired, shared, processed, and stored. The growth of cloud, IoT, and edge computing models presents severe data privacy concerns, especially in the healthcare sector. However, rigorous research to develop appropriate data privacy solutions in the healthcare sector is still lacking. This paper discusses the current state of privacy-preservation solutions in IoT and edge healthcare applications. It identifies the common strategies often used to include privacy by the intelligent edges and technologies in healthcare systems. Furthermore, the study addresses the technical complexity, efficacy, and sustainability limits of these methods. The study also highlights the privacy issues and current research directions that have driven the IoT and edge healthcare solutions, with which more insightful future applications are encouraged.

关键词： edge computing fog computing data privacy healthcare systems intelligent edges