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Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

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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

Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： nina A.Vasilieva Liudmila E Savinetskaya andrey V.Tchabovsky A.n.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

Irisin/BDnF signaling in the muscle-brain axis and circadian system: A review

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The Journal of Biomedical Research 2024年第1期38卷 1-16页

作者： Alexey n.Inyushkin Vitalii S.Poletaev Elena M.Inyushkina Igor S.Kalberdin andrey A.Inyushkin Department of Human&Animal Physiology Samara National Research UniversitySamara 443011Russia.

In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian *** entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian *** is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic *** recently identified myokine irisin is proposed to serve as an entraining non-photic signal of *** is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FnDC5)in response to *** from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the *** data suggest that FnDC5/irisin mediates the positive effects of physical activity on brain *** several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDnF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDnF is ***,the brain receptor for irisin remains *** the current review,the interactions of physical activity and the irisin/BDnF axis with the circadian system are reconceptualized.

关键词： irisin brain-derived neurotrophic factor peroxisome proliferator-activated receptorγcoactivator 1α circadian rhythm circadian system muscle-brain axis

Early neoproterozoic Granite-Gneisses of the Junggar Alataw(Southeastern Kazakhstan):Age,Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 67-82页

作者： nadezhda KAnYGInA andrey TRETYAKOV Dmitriy ALEXEIEV Kirill DEGTYAREV Anfisa SKOBLEnKO natalia SOLOSHEnKO Boris ERMOLAEV Geological Institute Russian Academy of SciencesMoscow 119017Russia A.n.Zavaritsky Institute of Geology and Geochemistry Ural Branch of the Russian Academy of SciencesYekaterinburg 620016Russia

The combined petrographic,petrological,geochemical and geochronological study of the neoproterozoic gneisses of the Sarychabyn and Baskan complexes of the Junggar Alataw of South Kazakhstan elucidate the Precambrian tectonic evolution of the Aktau–Yili *** is one of the largest Precambrian crustal blocks in the western Central Asian orogenic *** U-Pb single-grain zircon ages indicate that granite-gneisses formed from the same source and crystallised in the early neoproterozoic ca.930–920 *** chemical composition of gneisses corresponds to A2-type *** whole-rock nd isotopic characteristics(εnd(t)=−4.9 to−1.0 and Tnd(DM-2st)=1.9 to 1.7 Ga)indicate the involvement of Paleoproterozoic crustal rocks in magma *** neoproterozoic ca.930–920 Ma A-type granitoids in the Aktau–Yili terrane of South and Central Kazakhstan might reflect within-plate magmatism adjacent to the collisional belt or a local extension setting in back-arc areas of the continental arc.

关键词： granitoid magmatism geochemistry geochronology Sm-nd isotope systematics neoproterozoic Junggar Alataw Kazakhstan Central Asian orogenic belt

Enhancing crystal integrity and structural rigidity of CsPbBr_(3) nanoplatelets to achieve a narrow colorsaturated blue emission

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Light(Science & Applications) 2024年第5期13卷 985-997页

作者： Qianqian Huang Wenxu Yin Bo Gao Qingsen Zeng Dong Yao Hao Zhang Yinghe Zhao Weijia Zheng Jiaqi Zhang Xuyong Yang Xiaoyu Zhang andrey L.Rogach Key Laboratory of Automobile Materials MOE School of Materials Science&Engineeringand Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsJilin UniversityChangchunChina. State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunChina. State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubeiChina. Department of Chemistry University of VictoriaVictoriaBCCanada. Key Laboratory of Advanced Display and System Applications of Ministry of Education Shanghai UniversityShanghaiChina. Department of Materials Science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongHong Kong S.A.RChina

Quantum-confined CsPbBr_(3) perovskites are promising blue emitters for ultra-high-definition displays,but their soft lattice caused by highly ionic nature has a limited ***,we endow CsPbBr_(3) nanoplatelets(nPLs)with atomic crystal-like structural rigidity through proper surface engineering,by using strongly bound n-dodecylbenzene sulfonic acid(DBSA).A stable,rigid crystal structure,as well as uniform,orderly-arranged surface of these nPLs is achieved by optimizing intermediate reaction stage,by switching from molecular clusters to mono-octahedra,while interaction with DBSA resulted in formation of a Cs_(x)O monolayer shell capping the nPL *** a result,both structural and optical stability of the CsPbBr3 nPLs is enhanced by strong covalent bonding of DBSA,which inhibits undesired phase transitions and decomposition of the perovskite phase potentially caused by ligand ***,rather small amount of DBSA ligands at the nPL surface results in a short inter-nPL spacing in their closely-packed films,which facilitates efficient charge injection and *** photoluminescence of the produced CsPbBr_(3) nPLs is bright(nearly unity emission quantum yield)and peaks at 457 nm with an extremely narrow bandwidth of 3.7 nm at 80 K,while the bandwidth of the electroluminescence(peaked at 460 nm)also reaches a record-narrow value of 15 nm at room *** value corresponds to the CIE coordinates of(0.141,0.062),which meets Rec.2020 standards for ultra-high-definition displays.

关键词： temperature stability narrow

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet n.Toksumakov Olga G.Matveeva Dmitriy V.Grudinin Kirill V.Voronin Arslan Mazitov Konstantin V.Kravtsov Alexander V.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.novikov Ivan Kruglov Davit A.Ghazaryan andrey A.Vyshnevyy Aleksey V.Arsenin Valentyn S.Volkov Kostya S.novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. national Graphene Institute(nGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2S3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

An overview of progress in Mg-based hydrogen storage films

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Chinese Physics B 2019年第9期28卷 68-77页

作者： Lyu Jinzhe andrey M Lider Viktor n Kudiiarov Division for Experimental Physics School of Nuclear Science & Engineering National Research Tomsk Polytechnic University

Mg-based hydrogen storage materials are considered to be one of the most promising solid-state hydrogen storage materials due to their large hydrogen storage capacity and low cost. However, slow hydrogen absorption/desorption rate and excessive hydrogen absorption/desorption temperature limit the application of Mg-based hydrogen storage *** present paper reviews the advances in the research of Mg-based hydrogen storage film in recent years, including the advantage of the film, the function theory of fabricating method and its functional theory, and the influencing factors in the technological process. The research status worldwide is introduced in detail. By comparing pure Mg, Pd-caped Mg, nonpalladium capped Mg, and Mg alloy hydrogen storage films, an ideal tendency for producing Mg-based film is pointed out,for example, looking for a cheap metal element to replace the high-priced Pd, compositing Mg film with other hydrogen storage alloy of catalytic elements, and so on.

关键词： Mg-based hydrogen storage film Pd-caped Mg film Mg alloy film interlayer intermetallic cooperative effect

Microperforation of the human nail plate by radiation of erbium lasers

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Frontiers of Optoelectronics 2017年第3期10卷 299-307页

作者： andrey V. BELIKOV andrey n. SERGEEV Sergey n. SMIRnOV Anastasia D. TAVALInSKAYA Department of Laser Technologies and Systems Saint-Petersburg National Research University of Information Technologies Mechanics and Optics (ITMO University) Saint Petersburg 197101 Russia

The nail plate forms a barrier that limits the effectiveness of drug delivery in the treatment of nail diseases and prevents the outflow of fluid in the case of subungual hematoma formation. Microperforation of the nail plate through laser radiation can increase the effectiveness of drug delivery and ensure the possibility of blood outflow. This study detected and identified the type and threshold of effects that arise from exposing the nail plate to Yb,Er： Glass （λ = 1.54 μm） and Er：YLF （λ= 2.81 μm） laser radiation. The rate and efficiency of nail plate ablation by the radiation of these lasers were studied. The effect of the storage time of a freshly extracted nail plate in open air on its ablation rate by Er：YLF （ λ=2.81 μm） laser radiation was also investigated. The impact of the Yb,Er：Glass and Er：YLF laser pulses on the nail plate caused bleaching, carbonization, ablation with microcrater formation, and microperforation. The laser energy densities WE （thresholds） required for these effects were determined. The maximum ablation rate for Yb,Er：Glass laser radiation was 8 μm/pulse at WE = 91 ±2 J/cm2, whereas that for Er：YLF laser radiation was 12 μm/ pulse at WE= 10.5＋0.5 J/cm2. The maximum ablation efficiency for Yb,Er：Glass laser radiation was 0.1 μm/mJ at Ws = 10.5±0.5 J/cm2, whereas that for Er：YLF laser radiation was 4.6 μm/mJ at WE = 5.3±0.3 J/cm2. The laser ablation rate depends on the storage time and conditions of the freshly extracted nail plate. For example, when exposed to Er：YLF laser radiation, the laser ablation rate decreased by half from the initial maximum value in 96 h of air storage and returned to the initial value after 1 h of storage in distilled water.

关键词： Yb Er:Glass laser Er:YLF laser nail plate microperforation ablation rate ablation efficiency dehydration

Studies of ultrasonic dehydration efficiency

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： Vladimir n. KHMELEV andrey V. SHALUnOV Roman V. BARSUKOV Denis S. ABRAMEnKO andrey n. LEBEDEV Biysk Technological Institute (Branch) Altai State Technical University

The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products.

关键词： Drying Ultrasound Vibration system Drying chamber Processing (treatment) of agricultural products