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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

Dreicer Electric Field Definition and Runaway Electrons in Solar Flares

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Research in Astronomy and Astrophysics 2024年第2期24卷 180-184页

作者： Yu.T.Tsap A.v.Stepanov Yu.g.Kopylova Crimean Astrophysical Observatory of the Russian Academy of Sciences Nauchny298409Russia Pulkovo Observatory of the Russian Academy of Sciences Pulkovskoje Shosse65/1St.Petersburg196140Russia

We analyze electron acceleration by a large-scale electric field E in a collisional hydrogen plasma under the solar flare coronal conditions based on approaches proposed by Dreicer and Spitzer for the dynamic friction force of *** Dreicer electric field EDr is determined as a critical electric field at which the entire electron population runs *** regimes of strong(E≲E_(Dr))and weak(E≪E_(Dr))electric field are *** is shown that the commonly used formal definition of the Dreicer field leads to an overestimation of its value by about five *** critical velocity at which the electrons of the"tail"of the Maxwell distribution become runaway under the action of the sub-Dreiser electric fields turns out to be underestimated by√3 times in some works because the Coulomb collisions between runaway and thermal electrons are not taken into *** electron acceleration by sub-Dreicer electric fields generated in the solar corona faces difficulties.

关键词： acceleration of particles-Sun flares-Physical Data and Processes

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

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

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

Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana N.Nekrasova Andrei I.Fischer Natalia A.Nesterova Anatoliy v.Dobrodumov Anzhelika v.garshinina Olga D.Shuvaeva Natalya v.Zakharova Evgenii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(N-vinylpyrrolidone(vP),N-methyl-N-vinylacetamide(MvAA),N-methacryloyl glucosamine(MAg))and anionic comononer sodium styrene sulfonate(NaSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing N-vinylamide units(vP,MvAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAg-containing *** the case of NaSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiviral activity Cytotoxicity

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

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： D A Baghdasaryan v A Harutynyan E M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Physiology of medicinal and aromatic plants under drought stress

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The Crop Journal 2024年第2期12卷 330-339页

作者： Zohreh Emami Bistgani Allen v.Barker Masoud Hashemi Isfahan Agricultural and Natural Resources Research and Education Center Agricultural Research Education and Extension Organization(AREEO)Isfahan 81748-35117Iran Stockbridge School of Agriculture University of MassachusettsAmherstMA 01002USA

Drought poses a significant challenge,restricting the productivity of medicinal and aromatic *** strain induced by drought can impede vital processes like respiration and photosynthesis,affecting various aspects of plants’growth and *** response to this adversity,medicinal plants employ mechanisms such as morphological and structural adjustments,modulation of drought-resistant genes,and augmented synthesis of secondary metabolites and osmotic regulatory substances to alleviate the *** water scarcity can lead to leaf wilting and may ultimately result in plant *** cultivation and management of medicinal plants under stress conditions often differ from those of other *** is because the main goal with medicinal plants is not only to increase the yield of the above-ground parts but also to enhance the production of active ingredients such as essential *** elucidate these mechanisms of drought resistance in medicinal and aromatic plants,the current review provides a summary of recent literature encompassing studies on the morphology,physiology,and biochemistry of medicinal and aromatic plants under drought conditions.

关键词： Drought stress Medicinal and aromatic plants Phytochemistry Physiology