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Posture Detection of Heart Disease Using Multi-Head Attention Vision Hybrid(MHAVH)Model

Computers, Materials & Continua 2024年第5期79卷 2673-2696页

作者： Hina Naz Zuping Zhang Mohammed Al-Habib Fuad A.Awwad Emad A.A.Ismail Zaid Ali Khan School of Computer Science and Engineering Central South UniversityChangsha410003China Department of Quantitative analysis College of Business AdministrationKing Saud UniversityP.O.Box 71115Riyadh11587Saudi Arabia Electrical and Computer Engineering University of VictoriaVictoriaV9A1B8Canada

Cardiovascular disease is the leading cause of death *** disease causes loss of heart muscles and is also responsible for the death of heart cells,sometimes damaging their functionality.A person’s life may depend on receiving timely assistance as soon as ***,minimizing the death ratio can be achieved by early detection of heart attack(HA)*** the United States alone,an estimated 610,000 people die fromheart attacks each year,accounting for one in every four ***,by identifying and reporting heart attack symptoms early on,it is possible to reduce damage and save many lives *** objective is to devise an algorithm aimed at helping individuals,particularly elderly individuals living independently,to safeguard their *** address these challenges,we employ deep learning *** have utilized a vision transformer(ViT)to address this ***,it has a significant overhead cost due to its memory consumption and computational complexity because of scaling dot-product ***,since transformer performance typically relies on large-scale or adequate data,adapting ViT for smaller datasets is more *** response,we propose a three-in-one steam model,theMulti-Head Attention Vision Hybrid(MHAVH).Thismodel integrates a real-time posture recognition framework to identify chest pain postures indicative of heart attacks using transfer learning techniques,such as ResNet-50 and VGG-16,renowned for their robust feature extraction *** incorporatingmultiple heads into the vision transformer to generate additional metrics and enhance heart-detection capabilities,we leverage a 2019 posture-based dataset comprising RGb images,a novel creation by the author that marks the first dataset tailored for posture-based heart attack *** the limited online data availability,we segmented this dataset into gender categories(male and female)and conducted testing on both segmented and original dat

关键词： Image analysis posture of heart attack(PHA)detection hybrid features VGG-16 ResNet-50 vision transformer advance multi-head attention layer

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Transmit Power Minimization for IRS-Assisted NOMA-UAV Networks

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China Communications 2024年第5期21卷 137-152页

作者： Zhao Chen Pang Xiaowei Tang Jie Liu Mingqian Zhao Nan Zhang Xiuyin Wang Xianbin School of Information and Communication Engineering Dalian University of TechnologyDalian 116024China School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510641China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China Department of Electrical and Computer Engineering Western UniversityLondonON N6A 5B9Canada

The flexibility of unmanned aerial vehicles(UAVs)allows them to be quickly deployed to support ground *** reflecting surface(IRS)can reflect the incident signal and form passive beamforming to enhance the signal in the specific *** by the promising benefits of both technologies,we consider a new scenario in this paper where a UAV uses non-orthogonal multiple access to serve multiple users with *** to their distance to the UAV,the users are divided into the close users and remote *** UAV hovers above the close users due to their higher rate requirement,while the IRS is deployed near the remote users to enhance their received *** aim at minimizing the transmit power of UAV by jointly optimizing the beamforming of UAV and the phase shift of IRS while ensuring the decoding ***,the problem is ***,we decompose it into two sub-problems,including the transmit beamforming optimization and phase shift optimization,which are transformed into second-order cone programming and semidefinite programming,*** propose an iterative algorithm to solve the two sub-problems *** results prove the effectiveness of the proposed scheme in minimizing the transmit power of UAV.

关键词： intelligent reflecting surface nonorthogonal multiple access phase shift optimization transmit beamforming optimization unmanned aerial vehicle

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Thermochemical splitting of CO_(2) on perovskites for CO production: A review

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Journal of Energy Chemistry 2024年第3期90卷 464-485,I0011页

作者： biduan Chen Harriet Kildahl Hui Yang Yulong Ding Lige Tong Li Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Chemical Engineering University of BirminghamBirmingham B152TTUnited Kingdom beijing Engineering Research Centre of Energy Saving and Environmental Protection Beijing 100083China

Energy supply dominated by fossil energy has been and remains the main cause of carbon dioxide emissions,the major greenhouse gas leading to the current grave climate change *** technical pathways have been proposed to address the *** capture and utilization(CCU) represents one of the approaches and thermochemical CO_(2) splitting driven by thermal energy is a subset of the CCU,which converts the captured CO_(2) into CO and makes it possible to achieve closed-loop carbon ***-active catalysts are among the most critical components of the thermochemical splitting cycles and perovskites are regarded as the most promising *** we review the latest advancements in thermochemical cycles based on perovskites,covering thermodynamic principles,material modifications,reaction kinetics,oxygen pressure control,circular strategies,and demonstrations to provide a comprehensive overview of the topical *** cycles based on such materials require the consideration of trade-off between cost and efficiency,which is related to actual material used,operation mode,oxygen removal,and heat *** of efforts have been made towards improving reaction rates,conversion efficiency and cycling stability,materials related research has been lacking-a key aspect affecting the performance across all above *** perovskites and composite perovskites arise recently as a potentially promising addition to material *** such materials,more effective oxygen removal would be needed to enhance the overall efficiency,for which thermochemical or electrochemical oxygen pumps could contribute to efficient oxygen removal as well as serve as means for inert gas *** integration of thermochemical CO_(2) splitting process with downstream fuel production and other processes could reduce costs and increase efficiency of the *** represents one of the directions for the future research.

关键词： Perovskite Thermochemical cycles CO_(2) splitting Fuel production Non-stoichiometric

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Introduction of rare-earth element Sc in alloy design to modify wear features of dual-phase high-entropy alloy

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Rare Metals 2024年第2期43卷 817-828页

作者： Hao Ren Rui-Run Chen Xue-Feng Gao Tong Liu Gang Qin Yu-Lung Chiu Shi-Ping Wu Jing-Jie Guo Guo National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin150001China School of Metallurgy and Materials University of BirminghamBirminghamB152TTUK

Tailoring the alloy composition,which induces the hard secondary phase to increase hardness and strength to improve the wear features,is a feasible approach for developing wear-resistant metal ***,a group of(AlCoCrFeNi)_(100–x)Sc_(x)(x=0–2.0,at%)high-entropy alloys(HEAs)are designed and the phase compositions and wear behaviors are ***-doped HEA series contain the primary body-centered cubic(bCC)and eutectic phases,in which the eutectic phase is composed of the alternately grown bCC and Laves *** addition promotes the diffusion of Ni atoms from bCC phase to form the Sc-rich Laves phase at the grain *** hardness increases due to solid solution strengthening and second phase *** the second phase strengthening plays a more significant role relative to solid solution *** phase and the oxides caused by wear heating prevent the direct contact between friction pair and HEAs,thus inducing a decreased wear rate from 6.82×10^(−5) to 3.47×10^(−5)m^(3)·N^(−1)·m^(−1).Moreover,the wear mechanism changes from adhesive wear,abrasive wear and oxidative wear to abrasive wear and oxidative wear.

关键词： High entropy alloy(HEA) Laves phase Hardness Wear mechanism

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Poisoning effect of polyvinyl chloride on the catalytic pyrolysis of mixed plastics over zeolites

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Science China Chemistry 2024年第7期67卷 2265-2273页

作者： Jiangchun Yuan Wenjie Wang Weixiao Sun Zhirong Yang Yueqiang Cao Wenyao Chen Xiaohu Ge Gang Qian Xiang Feng Xuezhi Duan Xinggui Zhou Kevin M.Van Geem Jing Zhang State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Laboratory for Chemical Technology(LCT) Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering&ArchitectureGhent UniversityZwijnaarde B-9052Belgium State Key Lab of Heavy Oil Processing China University of PetroleumQingdao 266580China

Nowadays,the chemical recycling is applied for only 1%of total waste plastics,largely due to contaminants in plastic waste and difficulty in product *** the major contaminant,polyvinyl chloride(PVC)often forms corrosive hydrogen chloride(HCl)during the chemical recycling,which may cause severe catalyst deactivation and equipment ***,the investigation on catalytic pyrolysis(the major route for plastics chemical recycling)of the PVC containing mixed plastics has been rarely ***,catalytic co-pyrolysis of PVC and polyethylene(PE)was studied over an aromatization catalyst,Pt/ZSM-5,since the basic building block aromatics are desired products from plastics chemical *** poisoning effect of PVC vapor on the catalyst stability was explored by collective efforts of thorough product analysis and catalyst *** was found that the HCl evolving from PVC has an autocatalytic effect that promotes the scission of dehydrochlorinated PVC,resulting in the high yield of benzene and acetylene from *** the other hand,the presence of PVC suppressed the aromatics formation from PE,largely due to the poisoning effect of PVC-derived HCl on the Pt/*** deactivation is irreversible as evidenced by the decreased zeolite crystallinity and the loss of strong acid sites that are key to the aromatization,possibly due to the removal of framework Al upon the interaction with *** modification with octadecylphosphonic acid only slightly alleviated the PVC poisoning *** insights on the PVC poisoning of zeolite catalysts provided in this work may guide the process design of chemical recycling of PVC containing waste plastics.

关键词： polyvinyl chloride polyethylene zeolite aromatics deactivation

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Recent Research Progress of Paper-based Supercapacitors based on Cellulose

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Energy & Environmental Materials 2024年第3期7卷 345-373页

作者： Chuanyin Xiong Tianxu Wang Jing Han zhao Zhang Yonghao Ni College of bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Materials Science and Engineering Tianjin Polytechnic UniversityTianjin 300387China Department of Chemical and biomedical Engineering The University of MaineOronoMaine 04469USA university of New brunswick Limerick Pulp&Paper CtrFredericton New Brunswick E3B 5A3Canada

In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good *** an important energy storage device,paper-based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent *** present,researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage *** development of paper-based supercapacitors provides an important direction for the development of green and sustainable ***,it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and *** this review,the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites,preparation skills,and electrochemical ***,some opinions on the problems in the development of this field and the future development trend were *** is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.

关键词： cellulose electrochemical performance flexibility paper-based supercapacitor porous

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Seasonal changes in Hermit Thrush (Catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean P.Roach Luke C.McLean Jeff W.MacLeod Leslie S.Phillmore Psychology Department University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Department of Psychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a *** such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** species for which syntax has been thoroughly described is the Hermit Thrush(Catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency *** objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding *** hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most *** revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined *** song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate *** work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way.

关键词： birdsong Hermit Thrush Seasonal change Stereotypy Syntax

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Astronomical influence of the development of Paleogene thin coal seam groups in offshore Lacustrine basins:A case study of the ZhuⅠDepression's Enping Formation located in the northern South China Sea

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Acta Oceanologica Sinica 2024年第4期43卷 136-150页

作者： Yan Liu Shengbing Huang Dongdong Wang Nan Li Yuting Yin Ying Chen Zengxue Li College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China CNOOC Research Institute Co. Ltd.Beijing 100028China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTUK

The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stability,scattered vertical distribution,and a wide distribution *** study selected the Enping Formation of the ZhuⅠDepression in the northern section of the South China Sea as an example to determine the macro-control factors of the development of the Paleogene coal seam *** analysis was carried out on the influencing effects and patterns of the astronomical cycles related to the development of the thin coal seam groups in the region.A floating astronomical time scale of the Enping Formation was established,and the sedimentary time limit of the Enping Formation was determined to be approximately 6.15 Ma±.In addition,the cyclostratigraphy analysis results of the natural gamma-ray data of Well XJ in the Enping Formation of the Xijiang Sag revealed that the development of the thin coal seams had probably been affected by short eccentricity and precession *** formation process of coal seams was determined to have been affected by high seasonal contrast,precipitation,and *** the periods with high values of short eccentricity,the seasonal contrasts tended to be *** those periods,fluctuations in the precession controls resulted in periodic volume changes in precipitation and insolation of the region,resulting in the development of thin coal *** was also found that the periods with low precession were the most conducive to coal seam *** that basis,combined with such factors as sedimentary environmental conditions conducive to the development of thin coal seam groups,this study established a theoretical model of the comprehensive influences of short eccentricity and precession on the development and distribution of Paleogene thin coal seam groups in offshore lacustrine *** patterns of the Paleogene astrono

关键词： Paleogene Pearl(Zhujiang)River Mouth basin coal seam development astronomical cycles

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A Hf-doped dual-phase high-entropy alloy: phase evolution and wear features

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Rare Metals 2024年第1期43卷 324-333页

作者： Hao Ren Rui-Run Chen Xue-Feng Gao Tong Liu Gang Qin Yu-Lung Chiu Shi-Ping Wu Jing-Jie Guo National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China School of Metallurgy and Materials University of BirminghamEdgbastonBirmingham B152TTUK

Initially defined high entropy alloys(HEAs)usually exhibit a single-phase solid-solution ***,two and/or more types of phases in HE As possibly induce the desired microstructure features,which contribute to improving the wear properties of HE ***,we prepare a series of(AlCoCrFeNi)_(100-x)Hf_(x)(x=0,2,4and 6;at%) HEAs and concern their phase compositions,micro structures and wear *** leads to the formation of(Ni,Co)_(2)Hf-type Laves phase and tailors the microstructure from a body-centered cubic(bCC) singlephase structure to a hypoeutectic *** increased hardness from~HV 512.3 to~HV 734.1 is due to solid-solution strengthening,grain refinement strengthening and precipitated phase *** a few oxides(Al_(2)O_(3)+Cr_(2)O_(3)) caused by the wear heating contribute to an 85.5% decrease in wear rate of the HEA system from6.71×10^(-5) to 0.97×10^(-5) m^(3)·N^(-1)·m^(-1).In addition,Hf addition changes the wear mechanism from abrasive wear,mild oxidative wear and adhesive wear to oxidative wear and adhesive wear.

关键词： High entropy alloy Laves phase Hardness Wear mechanism

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Liquid injectivity in a SAG foam process:Effect of permeability

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Petroleum Science 2024年第1期21卷 302-314页

作者： Jia-Kun Gong Yuan Wang Ridhwan-Zhafri b.Kamarul bahrim Raj-Deo Tewari Mohammad-Iqbal Mahamad Amir Rouhi Farajzadeh William Rossen College of Mechanics and Materials Hohai UniversityNanjing210098JiangsuChina College of Water Conservancy&Hydropower Engineering Hohai UniversityNanjing210098JiangsuChina PETRONAS Kuala Lumpur50088Malaysia Department of Geoscience and Engineering Delft University of Technology2628 CNDelftthe Netherlands Shell Global Solutions International b.V. 1031 HWAmsterdamthe Netherlands

Foam is utilized in enhanced oil recovery and CO_(2) ***-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in *** previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct ***,underground reservoirs are heterogeneous,often *** is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG *** this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 *** observe the same sequence of banks in cores with different ***,the speed at which banks propagate and their overall mobility can vary depending on *** higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid *** total mobilities of both banks decrease with *** utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman *** findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman *** lower the formation permeability,the greater the error.

关键词： Foam Enhanced oil recovery Surfactant-alternating-gas Injectivity Permeability

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