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Defence Technology（防务技术） 2024年第1期31卷 537-543页

作者： Huang Hailong Mohsen Eskandari Andrey v.Savkin Wei Ni The Department of Aeronautical and Aviation Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Electrical Engineering and Telecommunications University of New South WalesSydney2052Australia Data61 CSIROAustralia

We consider a scenario where an unmanned aerial vehicle(UAv),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple *** friendly reconfigurable intelligent surfaces(RiSs) help to secure the UAv-target communication and improve the energy efficiency of the *** formulate an optimization problem to minimize the energy consumption of the UAv,subject to the mobility constraint of the UAv and that the achievable secrecy rate at the target is over a given *** present an online planning method following the framework of model predictive control(MPc) to jointly optimize the motion of the UAv and the configurations of the *** effectiveness of the proposed method is validated via computer simulations.

关键词： Unmanned aerial systems(UASs) Unmanned aerial vehicle(UAv) communication security Eaves-dropping Reconfigurable intelligent surfaces(RiS) Autonomous navigation and placement Path planning Model predictive control

Emission colour tuning in KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)phosphor

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Journal of Rare Earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri E vijayatha v Ramasubramanian S Thiyagarajan P Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),Er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/Er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth Er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,Er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,Er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using Uv light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths Energy transfer upconversion Downshifting colour coordinates

Severe aspiration pneumonia in the elderly

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Journal of intensive Medicine 2024年第3期4卷 307-317页

作者： Sebastian Ocrospoma Marcos i.Restrepo Division of Pulmonary Diseases&critical care Medicine University of Texas Health San AntonioSan AntonioTXUSA Section of Pulmonary&critical care Medicine South Texas Veterans Health Care SystemSan AntonioTXUSA

The global population is aging at an unprecedented rate,resulting in a growing and vulnerable elderly population in need of efficient comprehensive healthcare services that include long-term care and skilled nursing *** this context,severe aspiration pneumonia,a condition that carries substantial morbidity,mortality,and financial burden,especially among elderly patients requiring admission to the intensive care unit,has attracted greater *** pneumonia is defined as a pulmonary infection related to aspiration or dysphagia in *** episodes of coughing on food or liquid intake,a history of relevant underlying conditions,abnormalities on videofluoroscopy or water swallowing,and gravity-dependent shadow distribution on chest imaging are among the clues that suggest *** with aspiration pneumonia tend to be elderly,frail,and suffering from more comorbidities than those without this ***,we comprehensively address the epidemiology,clinical characteristics,diagnosis,treatment,prevention,and prognosis of severe aspiration community-acquired pneumonia in the elderly to optimize care of this high-risk demographic,enhance outcomes,and minimize the healthcare costs associated with this *** preventive measures and effective management strategies is vital in ensuring the well-being of our aging population.

关键词： Aspiration pneumonia Aged critical illness Swallowing disorders Frailty Antibacterial agents

Exploring the potential of drill cuttings for reservoir characterization:A case study from the volga-Ural basin,Russia

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Petroleum Research 2024年第2期9卷 193-205页

作者： ibrahem Yousef v.P.Morozov Kazan Federal University Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectives are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reservoir *** cutting samples were collected from a vertical well that penetrated the Domanik sediments(Semiluksk Formation)in one of the oil fields in the volga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio imager A2).X-ray diffraction(XRD)analyses were performed using a Brucker D2 Phaser X-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock-Eval *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations revealed that the carbonates are mainly limestone(mudstone and wackestone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rocks are dominated by siliceous mudstones and are characterized by dark colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rocks are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rocks are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the average total hydrocarbon in the carbonate and siliceous-carbonate rocks is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heavy hydrocarbons in the rocks is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,average S1 is 4.4 mg/g and average S2 is 19.8 mg/g(for the core samples);average S1 is 2.1 mg/g and average S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reservoir characterization Domanik Semiluksk volga-Ural Russia

Post processing of additive manufactured Mg alloys:current status,challenges,and opportunities

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Journal of Magnesium and Alloys 2024年第4期12卷 1283-1310页

作者： Nooruddin Ansari Fatima Ghassan Alabtah Mohammad i.Albakri Marwan Khraisheh Mechanical Engineering Program Texas A&M University at QatarP.O.Box 23874DohaQatar

Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight *** are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to *** ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing ***,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification *** leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg *** address these issues,post-processing of AM Mg alloys are often needed to make them suitable for *** present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface *** utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also *** post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are ***,future prospects and research directions are proposed.

关键词： Magnesium alloy Additive manufacturing Post-processing Heat treatment HiP

There is more to the knee joint than just the quadriceps:A systematic review with meta-analysis and evidence gap map of hamstring strength,flexibility,and morphology in individuals with gradual-onset knee disorders

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Journal of Sport and Health Science 2024年第4期13卷 521-536页

作者： Helder S.Lopes Marina c.Waiteman Liliam B.Priore Neal R.Glaviano David M.Bazett-Jones Ronaldo v.Briani Fabio M.Azevedo School of Science and Technology Physical Therapy DepartmentSao Paulo State University(UNESP)Presidente Prudente 19060-900Brazil Department of Kinesiology College of AgricultureHealth and Natural ResourcesUniversity of ConnecticutStorrsCT 06269USA School of Exercise and Rehabilitation Sciences College of Health and Human ServicesUniversity of ToledoToledoOH 43606USA

Background:impairments in hamstring strength,flexibility,and morphology have been associated with altered knee biomechanics,pain,and *** the presence of these impairments in individuals with gradual-onset knee disorders is important and may indicate targets for assessment and *** systematic review aimed to synthesize the literature to determine the presence of impairments in hamstring strength,flexibility,and morphology in individuals with gradual-onset knee ***:Five databases(MEDLiNE,Embase,ciNAHL,SPORTDiscus,and Web of Science)were searched from inception to September *** studies comparing hamstring outcomes(e.g.,strength,flexibility,and/or morphology)between individuals with gradual-onset knee disorders and their unaffected limbs or pain-free controls were ***-analyses for each knee disorder were ***-level certainty was assessed using the Grading of Recommendations Assessment,Development,and Evaluation,and evidence gap maps were ***:Seventy-nine studies across 4 different gradual-onset knee disorders(i.e.,knee osteoarthritis(OA),patellofemoral pain(PFP),chondromalacia patellae,and patellar tendinopathy)were *** with knee OA presented with reduced hamstring strength compared to pain-free controls during isometric(standard mean difference(SMD)=-0.76,95%confidence interval(95%ci):-1.32 to-0.21)and concentric contractions(SMD=-0.97,95%ci:-1.49 to-0.45).individuals with PFP presented with reduced hamstring strength compared to painfree controls during isometric(SMD=-0.48,95%ci:-0.82 to-0.14),concentric(SMD=-1.07,95%ci:-2.08 to-0.06),and eccentric contractions(SMD=-0.59,95%ci:-0.97 to-0.21).No differences were observed in individuals with patellar *** with PFP presented with reduced hamstring flexibility when compared to pain-free controls(SMD=-0.76,95%ci:-1.15 to-0.36).Evidence gap maps identified insufficient evidence for chondromalacia patel

关键词： chondromalacia patellae Knee flexors Knee osteoarthritis Patellar tendinopathy Patellofemoral pain

coopAi-Route: DRL Empowered Multi-Agent cooperative System for Efficient QoS-Aware Routing for Network Slicing in Multi-Domain SDN

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computer Modeling in Engineering & Sciences 2024年第9期140卷 2449-2486页

作者： Meignanamoorthi Dhandapani v.vetriselvi R.Aishwarya college of Engineering Guindy Anna UniversityChennai600025India

The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global *** slicing is crucial in delivering services for different,demanding vertical applications in this ***-generation applications have time-sensitive requirements and depend on the most efficient routing path to ensure packets reach their intended ***,the existing iP(internet Protocol)over a multi-domain network faces challenges in enforcing network slicing due to minimal collaboration and information sharing among network *** inter-domain routing methods,like Border Gateway Protocol(BGP),cannot make routing decisions based on performance,which frequently results in traffic flowing across congested paths that are never *** address these issues,we propose coopAi-Route,a multi-agent cooperative deep reinforcement learning(DRL)system utilizing hierarchical software-defined networks(SDN).This framework enforces network slicing in multi-domain networks and cooperative communication with various administrators to find performance-based routes in intra-and ***-Route employs the Distributed Global Topology(DGT)algorithm to define inter-domain Quality of Service(QoS)***-Route uses a DRL agent with a message-passing multi-agent Twin-Delayed Deep Deterministic Policy Gradient method to ensure optimal end-to-end routes adapted to the specific requirements of network slicing *** evaluation demonstrates coopAi-Route’s commendable performance in scalability,link failure handling,and adaptability to evolving topologies compared to state-of-the-art methods.

关键词： 6G multi-domain multi-agent routing DRL SDN

Nonlinear-Optical Analogies in Nuclear-Like Soliton Reactions:Selection Rules,Nonlinear Tunneling and Sub-Barrier Fusion–Fission

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chinese Physics Letters 2024年第8期41卷 1-7页

作者： T.L.Belyaeva v.N.Serkin Universidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen chris R.Burke Jennie E.Pryce Nicole M.Steele Peter R.Amer Susanne Meier claire v.c.Phyn Dorian J.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL Rae centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture victoria Research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of Applied Systems Biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subject to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGEP4),which generally coincides with onset of puberty,as an example *** We produced AGEP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×Jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(EBvs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： cattle Gibbs sampler Markov-chain Monte carlo(McMc) Puberty

Distributed Dynamic Load in Structural Dynamics by the impulse-Based Force Estimation Algorithm

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computer Modeling in Engineering & Sciences 2024年第6期139卷 2865-2891页

作者： Yuantian Qin Yucheng Zhang vadim v.Silberschmidt college of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing210016China Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE113TUUK

This paper proposes a novel approach for identifying distributed dynamic loads in the time *** polynomial andmodal analysis,the load is transformed intomodal space for coefficient *** allows the distributed dynamic load with a two-dimensional form in terms of time and space to be simultaneously identified in the form of modal force,thereby achieving dimensionality *** impulse-based Force Estimation Algorithm is proposed to identify dynamic loads in the time ***,the algorithm establishes a recursion scheme based on convolution integral,enabling it to identify loads with a long history and rapidly changing forms over ***,the algorithm introduces moving mean and polynomial fitting to detrend,enhancing its applicability in load *** aforementioned methodology successfully accomplishes the reconstruction of distributed,instead of centralized,dynamic loads on the continuum in the time domain by utilizing acceleration *** validate the effectiveness of the method,computational and experimental verification were conducted.

关键词： Distributed force estimation time domain deconvolution recursion