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A Deep Reinforcement Learning-Based Technique for Optimal Power Allocation in Multiple Access Communications

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Intelligent Automation & Soft Computing 2024年第1期39卷 93-108页

作者： Sepehr Soltani ehsan Ghafourian Reza Salehi Diego Martín Milad Vahidi Department of Industrial engineering College of EngineeringUniversity of HoustonHoustonTX77204USA Department of Computer Science Iowa State UniversityAmesIowaUSA eTSI de Telecomunicación Universidad Politécnica de MadridMadridSpain Faculty of School of Plant and environmental Sciences Virginia Polytechnic Institute and StateUniversityBlacksburgVirginia24060USA

Formany years,researchers have explored power allocation(PA)algorithms driven bymodels in wireless networks where multiple-user communications with interference are ***,data-driven machine learning methods have become quite popular in analyzing wireless communication systems,which among them deep reinforcement learning(DRL)has a significant role in solving optimization issues under certain *** this purpose,in this paper,we investigate the PA problem in a k-user multiple access channels(MAC),where k transmitters(e.g.,mobile users)aim to send an independent message to a common receiver(e.g.,base station)through wireless *** this end,we first train the deep Q network(DQn)with a deep Q learning(DQL)algorithm over the simulation environment,utilizing offline ***,the DQn will be used with the real data in the online training method for the PA issue by maximizing the sumrate subjected to the source ***,the simulation results indicate that our proposedDQnmethod provides better performance in terms of the sumrate compared with the available DQL training approaches such as fractional programming(FP)and weighted minimum mean squared error(WMMSe).Additionally,by considering different user densities,we show that our proposed DQn outperforms benchmark algorithms,thereby,a good generalization ability is verified over wireless multi-user communication systems.

关键词： Deep reinforcement learning deep Q learning multiple access channel power allocation

Prompt neutron emission in ^(250)no spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： R.S.Mukhin A.V.Isaev A.V.Andreev M.L.Chelnokov V.I.Chepigin H.M.Devaraja I.n.Izosimov A.A.Kuznetsova O.n.Malyshev A.G.Popeko Yu.A.Popov A.Rahmatinejad B.Sailaubekov T.M.Shneidman e.A.Sokol A.I.Svirikhin M.S.Tezekbayeva M.A.Bychkov A.V.Yeremin O.Dorvaux B.Gall K.Kessaci K.Hauschild A.Lopez-Martens Joint Institute for nuclear Research Dubna141980Russia Dubna State University Dubna141982Russia Institute of nuclear Physics Almaty050032Kazakhstan L.n.Gumilyov eurasian national University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France IJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)no was used to study two activities of^(250)no with distinct half-lives.A total of 1357 events were observed in the SFinx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)no was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

A machine learning driven 3D+1D model for efficient characterization of proton exchange membrane fuel cells

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energy and AI 2024年第3期17卷 281-294页

作者： Yuwei Pan Haijun Ruan Billy Wu Yagya n.Regmi Huizhi Wang nigel P.Brandon Department of earth Science and engineering Imperial College LondonLondon SW72AZUK Dyson School of Design engineering Imperial College LondonLondon SW72AZUK Centre for e-Mobility and Clean Growth Coventry UniversityCoventry CV15FBUK Manchester Fuel Cell Innovation Centre Department of Natural SciencesManchester Metropolitan UniversityManchester M15GDUK Department of Mechanical engineering Imperial College LondonLondon SW72AZUK

The computational demands of 3D continuum models for proton exchange membrane fuel cells remain substantial. One prevalent approach is the hierarchical model combining a 2D/3D flow field with a 1D sub-model for the catalyst layers and membrane. However, existing studies often simplify the 1D domain to a linearized 0D lumped model, potentially resulting in significant errors at high loads. In this study, we present a computationally efficient neural network driven 3D+1D model for proton exchange membrane fuel cells. The 3D sub-model captures transport in the gas channels and gas diffusion layers and is coupled with a 1D electrochemical sub-model for microporous layers, membrane, and catalyst layers. To reduce computational intensity of the full 1D description, a neural network surrogates the 1D electrochemical sub-model for coupling with the 3D domain. Trained by model-generated large synthetic datasets, the neural network achieves root mean square errors of less than 0.2%. The model is validated against experimental results under various relative humidities. It is then employed to investigate the nonlinear distribution of internal states under different operating conditions. With the neural network operating at 0.5% of the computing cost of the 1D sub-model, the hybrid model preserves a detailed and nonlinear representation of the internal fuel cell states while maintaining computational costs comparable to conventional 3D+0D models. The presented hybrid data-driven and physical modeling framework offers high accuracy and computing speed across a broad spectrum of operating conditions, potentially aiding the rapid optimization of both the membrane electrode assembly and the gas channel geometry.

关键词： Proton exchange membrane fuel cell Hierarchical model neural network Hybrid model

Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.V.nadaraia D.V.Mashtalyar M.A.Piatkova A.I.Pleshkova I.M.Imshinetskiy M.S.Gerasimenko e.A.Belov V.V.Kumeiko D.n.Kozyrev K.A.Fomenko V.V.Mostovaya B.R.Torpanov A.R.Biktimirov I.S.Osmushko S.L.Sinebryukhov S.V.Gnedenkov Institute of Chemistry FeB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.V.Zhirmunsky national Scientific Center of Marine Biology FeB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia nMIC“Treatment and Rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

In this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PeO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SeM,eDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PeO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PeO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite Vancomycin

Thermodynamic analysis of metal segregation in dual phase high entropy ceramics

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Journal of Materiomics 2024年第4期10卷 889-895页

作者： Steven M.Smith II William G.Fahrenholtz Gregory e.Hilmas Stefano Curtarolo Missouri University of Science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke University Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke University Center of Autonomous Materials DesignDurhamNC27708USA

equilibrium Gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy *** model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,nb,Mo,V,Hf,and Ta,which matches experimental results of measured *** ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard Gibbs'free energy of reaction for a metal carbide reacting with B_(4)C to produce its corresponding metal boride and *** proposed model was used to predict the changes in standard Gibbs'free energy for CrC→CrB_(2) to be−260 kJ and WC→WB_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关键词： Dual phase High entropy ceramic Boride Carbide Thermodynamics

Surface modification of HKUST-1 for enhanced activity of immobilized formate dehydrogenase used in CO_(2)hydrogenation

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Carbon Resources Conversion 2024年第1期7卷 89-102,F0004页

作者： Shadeera Rouf Yaser e.Greish Bart Van der Bruggen Sulaiman Al-Zuhair Department of Chemical and Petroleum engineering UAE University15551 Al AinUnited Arab Emirates Department of Chemistry UAE University15551 Al AinUnited Arab Emirates Department of Chemical engineering KU Leuven3000 LeuvenBelgium

Post synthetic modification of a hydrophilic metal-organic framework(MOF),HKUST-1,with stearic acid(SA)was carried out to enhance the stability of HKUST-1 in aqueous solution to be used as a support for formate dehydrogenase(FDH)used for CO_(2)conversion to *** modification improved the hydrophobicity without affecting the morphology and crystal structure of *** of FDH on the modified MOF(SA@HKUST-1)was compared to that of the native HKUST-1 and *** adsorption kinetics on all MOFs was found to follow pseudo-second order kinetics and the isotherm was best described by Freundlich *** high stability of SA@HKUST-1 and enhanced hydrophobic interaction between support and CO_(2)resulted in high catalytic efficiency and stability of FDH@SA@*** immobilized enzyme retained 95.1%of its initial activity after 4 cycles of repeated *** was also shown that FDH@SA@HKUST-1 retained morphology and crystal structure after repeated *** of the present work provide novel insight into the influence of hydrophobic MOFs on the activity and stability of immobilized *** findings are expected to assist in developing highly active and stable biocatalysts for CO_(2)hydrogenation at commercial level.

关键词： CO_(2)hydrogenation Formate dehydrogenase Metal organic frameworks Hydrophobic MOFs Formate

Influence of previous plane of nutrition on molecular mechanisms regulating the expression of urea and water metabolism related genes in the rumen and kidney of finishing crossbred Angus steers

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Animal nutrition 2024年第2期17卷 232-243页

作者： Aghata e.Moreira da Silva Arturo Macias Franco Bradley S.Ferguson Mozart A.Fonseca College of Agriculture Biotechnology&Natural Resources University of Nevada Department of Animal and Range Sciences Clayton Livestock Research Center New Mexico State University

This study aimed to understand how molecular mechanisms controlling water and urea metabolism at the finishing phase can be affected by previous plane of nutrition of crossbred Angus beef steers. Twentyfour(n = 24) animals were randomly distributed into either a moderate(MP) or high plane of nutrition during the background phase for 85 d. Animals were then blocked by their previous plane and were moved onto a 105-d finishing phase in a 2 × 2 factorial arrangement. The forage-finished group received only high-quality alfalfa hay, whereas the grain-fed group received a high grain diet(80% whole corn and20% alfalfa hay). By the end of the finishing phase, animals were harvested and tissue samples from the rumen and kidney were collected. Changes in gene expression of aquaporins(AQP)-2,-3,-4,-7, ATP1A1,ATP1B1, SGK1, CLIC1(kidney and rumen), UT-A1(kidney only) and UT-B(rumen only), were assayed via real-time q PCR; 18S r RnA was used as an endogenous control. One-way AnOVA followed by Tukey's post hoc analysis was conducted. When animals were from MP, forage-finishing increased the relative abundance of AQP3(P ≤ 0.05), AQP7(P ≤ 0.05), ATP1B1(P ≤ 0.05), and SGK1(P ≤ 0.05) in the kidney when compared to grain-fed animals. In the rumen, for the MP group, AQP7 was differentially expressed in both treatments at the finishing phase(P ≤ 0.01), with forage-finished steers having the highest expression of AQP7. For the MP group, UT-B had a tendency of presenting a higher expression on grainfed animals(P = 0.075). Overall, these results suggest that previous plane can impact expression of genes associated with water and urea metabolism during the finishing phase, namely AQP3, AQP7, ATP1B1, and SGK1 in the kidney, and AQP7 and UT-B in the rumen. The greatest impact observed on gene expression changes of investigated genes at the finishing phase was reflective of animals backgrounded on the moderate previous plane.

关键词： Gene expression Aquaporin Sodium channel Urea transporter

Infectious causes of fever of unknown origin in developing countries: An international ID-IRI study

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Journal of Intensive Medicine 2024年第1期4卷 94-100页

作者： Hakan erdem Jaffar AAl-Tawfiq Maha Abid Wissal Ben Yahia George Akafity Manar ezzelarab Ramadan Fatma Amer Amani el-Kholy Atousa Hakamifard Bilal Ahmad Rahimi Farouq Dayyab Hulya Caskurlu Reham khedr Muhammad Tahir Lysien Zambrano Mumtaz Ali Khan Aun Raza nagwa Mostafa el-Sayed Magdalena Baymakova Aysun Yalci Yasemin Cag Umran elbahr Aamer Ikram Department of Infectious Diseases&Clinical Microbiology Gulhane School of MedicineTurkish Health Sciences UniversityAnkaraTurkey Specialty Internal Medicine and Quality and Patient Safety Department Johns Hopkins Aramco HealthcareDhahranSaudi Arabia Division of Infectious Diseases Indiana University School of MedicineIndianapolisINUSA Department of Infectious Diseases Farhat Hached University HospitalIbn El Jazzar Medical SchoolUniversity of SousseSousseTunisia Internal Medicine Department Farhat Hached University HospitalIbn El Jazzar Medical SchoolUniversity of SousseSousseTunisia Cape Coast Teaching Hospital Cape CoastGhana Medical Parasitology Faculty of MedicineSuez UniversitySuezEgypt Department of Medical Microbiology and Immunology Faculty of MedicineZagazig UniversityZagazigEgypt Department of Clinical Pathology Faculty of MedicineCairo UniversityGizaEgypt Department of Infectious Diseases School of MedicineIsfahan University of Medical SciencesIsfahanIran Department of Infectious Diseases Kandahar University Medical FacultyTeaching HospitalKandaharAfghanistan Department of Infectious Diseases Mohammed Bn Khalifa Bn Salman Alkhalifa Specialist Cardiac CenterAwaliBahrain Department of Infectious Diseases and Clinical Microbiology Faculty of MedicineIstanbul Medeniyet UniversityIstanbulTurkey Department of Pediatric Oncology National Cancer Institute–Cairo UniversityChildren Cancer Hospital EgyptCairoEgypt Department of Medicine Federal General HospitalIslamabadPakistan Institute for Research in Medical Sciences and Right to Health(ICIMeDeS) Scientific Research Unit(UIC)Faculty of Medical Sciences(FCM)National Autonomous University of Honduras(UNAH)TegucigalpaHonduras national Institute of Health IslamabadPakistan Shaukat Khanum Memorial Cancer Hospital and Research Center LahorePakistan Medical Parasitology Department Research Institute of OphthalmologyGizaEgypt Department of Infectious Diseases Military Medical AcademySofiaBulgaria Department of Infecti

Background:Fever of unknown origin(FUO)in developing countries is an important dilemma and further research is needed to elucidate the infectious causes of ***:A multi-center study for infectious causes of FUO in lower middle-income countries(LMIC)and lowincome countries(LIC)was conducted between January 1,2018 and January 1,*** total,15 participating centers from seven different countries provided the data,which were collected through the Infectious DiseasesInternational Research Initiative *** adult patients with confirmed infection as the cause of FUO were included in the *** severity parameters were quick Sequential Organ Failure Assessment(qSOFA)≥2,intensive care unit(ICU)admission,vasopressor use,and invasive mechanical ventilation(IMV).Results:A total of 160 patients with infectious FUO were included in the ***,148(92.5%)patients had community-acquired infections and 12(7.5%)had hospital-acquired *** most common infectious syndromes were tuberculosis(TB)(n=27,16.9%),infective endocarditis(n=25,15.6%),malaria(n=21,13.1%),brucellosis(n=15,9.4%),and typhoid fever(n=9,5.6%).Plasmodium falciparum,Mycobacterium tuberculosis,Brucellae,Staphylococcus aureus,Salmonella typhi,and Rickettsiae were the leading infectious agents in this study.A total of 56(35.0%)cases had invasive procedures for *** mean qSOFA score was 0.76±0.94{median(interquartile range[IQR]):0(0–1)}.ICU admission(n=26,16.2%),vasopressor use(n=14,8.8%),and IMV(n=10,6.3%)were not ***,38(23.8%)patients had at least one of the severity *** mortality rate was 15(9.4%),and the mortality was attributable to the infection causing FUO in 12(7.5%)***:In LMIC and LIC,tuberculosis and cardiac infections were the most severe and the leading infections causing FUO.

关键词： Developing countries Fever of unknown origin Infection

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi e.Diez J.e.Velázquez-Pérez Y.M.Meziani J.M.Caridad J.A.Delgado-notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de excelencia en Luz y Materia estructurada(LUMeS) University of Salamanca37008 SalamancaSpain Research Center for electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFeTs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFeT *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic