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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

Analyzing the Essay Writing Patterns of Iranian Intermediate-Level Korean Language Learners: A Study Based on the TOPIK Exam

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Sino-US English Teaching 2024年第8期21卷 354-371页

作者： Vahid reza Nasrollahi Seoul National University SeoulSouth Korea

This study examines the writing abilities of Iranian intermediate Korean learners,specifically their performance in the compositional writing section of the Test of Proficiency in Korean(TOPIK).By utilizing the many FACETS-Rasch Model,we meticulously analyzed nine writing samples from the 52nd *** samples were evaluated using a modified rubric ranging from 0 to 3 based on predefined criteria for written *** results underscored that the sections on“appropriateness of spacing and spelling,”“relevance of vocabulary,”and“content diversity”presented the most significant challenges for the *** the other hand,“the quantity of writing”emerged as the least challenging *** findings reveal substantial disparities in various aspects of writing proficiency among *** study not only pinpoints issue areas in writing skills,but also underscores the necessity of customized teaching strategies within the TOPIK framework to address these ***,it offers valuable insights that could bolster the effectiveness of teaching writing to Korean language *** findings of this study are not only significant for the field of language education,but also contribute to a deeper understanding of the challenges faced by intermediate learners and provide a roadmap for improving language instruction.

关键词： TOPIK writing evaluation Iranian intermediate Korean learners multinational research analysis writing challenges language education strategies

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未热解厚热障涂层的隔热能力和黏接强度

Transactions of Nonferrous Metals Society of China 2024年第4期34卷 1226-1236页

作者： Mohammad IZADINIA reza SOLTANI Mahmoud HEYDARZADEH SOHI Javad MOSTAGHIMI School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehranIran Centre for Advanced Coating Technologies Department of Mechanical and Industrial EngineeringUniversity of TorontoTorontoOntarioCanada

对比研究使用未热解粉末制备的厚热障涂层(UPTTBC)和传统TBC、厚TBC(TTBC)及密集垂直裂纹(DVC)TTBC 4种涂层的隔热能力和黏接强度。采用降温法测试涂层的隔热能力;根据ASTM C633标准,采用拉拔试验检测涂层的黏接强度。结果显示,UPTTBC和... 详细信息

对比研究使用未热解粉末制备的厚热障涂层(UPTTBC)和传统TBC、厚TBC(TTBC)及密集垂直裂纹(DVC)TTBC 4种涂层的隔热能力和黏接强度。采用降温法测试涂层的隔热能力;根据ASTM C633标准,采用拉拔试验检测涂层的黏接强度。结果显示,UPTTBC和DVC TTBC的黏接强度分别比TTBC高35%和25%。这可能是由于UPTTBC结构中存在亚微米尺度的未熔化区域,起到了阻止裂纹扩展的作用。此外,隔热测试的结果表明,DVCTTBC涂层的隔热能力最差,为0.28℃/μm,而UPTTBC涂层的隔热能力最强,为0.40℃/μm。由于UPTTBCs显微组织中存在亚微米区域,使涂层展现出优越的隔热能力。相反,DVCTTBC因其致密的结构,具有最低的隔热能力。

关键词：厚热障涂层密集垂直裂纹热障涂层未热解粉末黏接强度隔热能力

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Investigation of parameters influencing erosive wear using DEM

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Friction 2020年第1期8卷 136-150页

作者： Akbar JAFARI reza abbasi HATTANI Department of Mechanical Engineering Sirjan University of TechnologySirjan ***Iran

The effects of several parameters on the erosive wear were studied using the discrete element method(DEM).The Finnie model was implemented using an open‐source *** the time integration,the Gear algorithm was used,and to ensure the accuracy of the DEM results,a time‐step sensitivity analysis was *** problem was modeled in two parts:first,the impact of a single particle on a surface was modeled,and then a more general model was prepared to examine the wear of surfaces under the flow of *** effects of the surface area,impact angle,speed,particle size,particle density,Young’s modulus,Poisson’s ratio,and restitution coefficient on the wear were studied numerically,and the results are discussed herein.

关键词： wear erosion Finnie discrete element

Correlation between critical thinking and emotional intelligence:a national crosssectional study on operating room nursing students in Iran

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Frontiers of Nursing 2024年第1期11卷 99-104页

作者： Armin Fereidouni Esmaeil Teymoori Tayebeh Bahmani Hamid reza Sabet Zahra Maleki Mina Gharibi Department of Operating Room Technology Community Based Psychiatric Care Research CenterSchool of Nursing and MidwiferyShiraz University of Medical SciencesShirazIran Department of Operating Room Technology School of Paramedical SciencesAJA University of Medical SciencesTehranIran Department of Operating Room School of Allied Medical ScienceFasa University of Medical SciencesFasaIran Clinical Education Research Center Shiraz University of Medical SciencesShirazIran Medical Journalism Department School of Paramedical SciencesShiraz University of Medical SciencesShirazIran Department of Epidemiology Student Research CommitteeShiraz University of Medical SciencesShirazIran

Objective:According to the World Federation of Medical Education,critical thinking should be part of the training of medical and paramedical *** can improve the quality of care of patients after surgery by having or acquiring this skill in health ***,Emotional intelligence is introduced as an impor tant and effective factor on the professional performance and mental health of healthcare ***,the present study was designed and implemented to determine the relationship between emotional intelligence and critical thinking among operating room nursing students of medical sciences universities in ***:This cross-sectional study was done on 420 operating room students in 10 top medical sciences universities of Iran in *** sampling method in this research was multistage *** data collection instruments included demographic characteristics,Rickett's critical thinking,and Bradberry-Greaves'emotional intelligence *** receiving the ethics code,data collection was done for 2 *** data analysis,descriptive and inferential analyses including independent t-tests,analysis of variance,and Pearson correlation were *** collected data were analyzed by SPSS 18(IBM Corporation,Armonk,New York,United States).P-value<0.05 was considered ***:The mean age of the students participating in this study was 23.02±3.70 years,with women constituting 67.4%of *** results of data analysis indicated that the mean total score of critical thinking and emotional intelligence was 124.10±37.52 and 114.12±43.63,respectively.A direct significant correlation between critical thinking and emotional intelligence(r=0.459,P-value<0.001)and a significant relationship between gender and emotional intelligence(P-value=0.028)were ***:Based on the present study results,educational managers in the Ministry of Health are suggested to consider suitable educational programs for improving critical think

关键词： critical thinking emotional intelligence operating room students operating room nurses

Magnetic polyacrylonitrile/ZIF-8/Fe_(3)O_(4) nanocomposite bead as an efficient iodine adsorbent and antibacterial agent

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Chinese Journal of Chemical Engineering 2023年第9期61卷 210-220页

作者： reza Sacourbaravi Zeinab Ansari-asl Esmaeil Darabpour Department of Chemistry Faculty of ScienceShahid Chamran University of AhvazAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran

The efficient adsorption of radioactive iodine(^(129)I and^(131)I)as nuclear waste is of great *** nanocomposites consist of metal-organic frameworks(MOFs)developing for various pollutions sorption and separation have attracted much *** study reports the fabrication of magnetic polyacrylonitrile(PAN)/zeolitic imidazolate frameworks(ZIF-8)nanocomposites,PAN/ZIF-8(x%)/Fe_(3)O_(4),x=30 and 50,as iodine capture *** PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposite beads were fabricated via the phase inversion method,and their potential for iodine capture and separation in solution and vapor was investigated through UV-vis and weighing methods,***,antibacterial activity of the as-prepared beads was assessed against *** and *** as-fabricated compounds were studied by various techniques such as Fourier-transform infrared,X-ray diffraction,scanning electron microscope,energy-dispersive X-ray spectroscopy mapping,transmission electron microscope,N_(2)adsorption isotherm,and vibrating sample *** iodine capture results showed that the efficiency of nanocomposites is remarkably higher than the pure PAN ***,the asprepared nanocomposite adsorbents displayed higher capture capacities for iodine vapor(1524-4345mg·g^(-1))than iodine solution(187-295 mg·g^(-1)).The as-obtained magnetic nanocomposites can be successfully separated from polluted media by simple filtration or an external magnet,regenerated through washing with ethanol,and *** capturing,high sorption capacity,rapid separation,and good reusability make the PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposites highly effective adsorbents for the separation of iodine from ***,PAN/ZIF-8(50%)/Fe_(3)O_(4)bead can be considered as a potential new antibacterial agent for water and wastewater treatment.

关键词： ZIF-8 Polyacrylonitrile Composites Adsorption Waste treatment Antibacterial agent

Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis

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Journal of Sport and Health Science 2024年第2期13卷 186-194页

作者： Andreas Konrad Shahab Alizadeh Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri reza Goudini Chris Edwards Carina Scharf David George Behm Institute of Human Movement Science Sport and HealthGraz UniversityGraz A-8010Austria School of Human Kinetics and Recreation Memorial University of NewfoundlandSt.John’sNL A1C 5S7Canada Department of Sport Injuries and Corrective Exercises Faculty of Sport SciencesShahid Bahonar University of KermanKerman 76169-13439Iran

Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in ***,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch ***:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect ***,by applying a mixed-effect model,we performed the respective subgroup *** find potential relationships between stretch duration or age and effect sizes,we performed a ***:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic ***,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to ***,further moderating analysis showed no significant relation or ***:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be *** to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were

关键词： Flexibility Long-term stretching Stretch training

人工神经网络与遗传算法预测液体晃荡参数的比较

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 292-301页

作者： Hassan Saghi Mohammad reza Sarani Nezhad reza Saghi Sepehr Partovi Sahneh Department of Civil Engineering Hakim Sabzevari UniversitySabzevarIran Department of Electrical and Computer Engineering University of BirjandBirjandIran State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian116024China Department of Marine Engineering Amirkabir University of TechnologyTehranIran

This paper develops a numerical code for modelling liquid *** coupled boundary element-finite element method was used to solve the Laplace equation for inviscid fluid and nonlinear free surface boundary *** Nakayama and Washizu’s results,the code performance was *** the developed numerical mode,we proposed artificial neural network(ANN)and genetic algorithm(GA)methods for evaluating sloshing loads and comparing *** compare the efficiency of the suggested methods,the maximum free surface displacement and the maximum horizontal force exerted on a rectangular tank’s perimeter are *** can be seen from the results that both ANNs and GAs can accurately predict η_(max) and F_(max).

关键词： Sloshing loads Fluid structure interactions Potential flow analysis Artificial neural network Genetic algorithm

Alleviation of spike stall in axial compressors utilizing grooved casing treatment

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Chinese Journal of Aeronautics 2015年第3期28卷 649-658页

作者： reza Taghavi-Zenouz Sarallah abbasi School of Mechanical Engineering Iran University of Science and Technology School of Mechanical Engineering Arak University of Technology

Abstract This article deals with application of grooved type casing treatment for suppression of spike stall in an isolated axial compressor rotor blade row. The continuous grooved casing treatment covering the whole compressor circumference is of 1.8 mm in depth and located between 90% and 108% chord of the blade tip as measured from leading edge. The method of investigation is based on time-accurate three-dimensional full annulus numerical simulations for cases with and without casing treatment. Discretization of the Navier Stokes equations has been carried out based on an upwind second-order scheme and k-a-SST （Shear Stress Transport） turbulence modeling has been used for estimation of eddy viscosity. Time-dependent flow structure results for the smooth casing reveal that there are two criteria for spike stall inception known as leading edge spillage and trailing edge backftow, which occur at specific mass flow rates in near-stall conditions. In this case, two dominant stall cells of different sizes could be observed. The larger one is caused by the spike stall covering roughly two blade passages in the circumferential direction and about 25% span in the radial direction. Spike stall disturbances are accompanied by lower frequencies and higher amplitudes of the pressure signals. Casing treatment causes flow blockages to reduce due to allevi- ation of backflow regions, which in turn reduces the total pressure loss and increases the axial veloc- ity in the blade tip gap region, as well as tip leakage flow fluctuation at higher frequencies and lower amplitudes. Eventually, it can be concluded that the casing treatment of the stepped tip gap type could increase the stall margin of the compressor. This fact is basically due to retarding the movement of the interface region between incoming and tip leakage flows towards the rotor leading edge Diane and suttressing the reversed flow around the blade trailing edee.

关键词： Axial compressor Casing treatment Frequency spectrum Spike stall inception Tip leakage flow