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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

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

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

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert P.Hesselbach M.Schorner v.Bagnoud R.belikov P.Drechsel B.Heuser O.SHumphries P.Katrik B.Lindqvist C.Qu R.Redmer D.Riley G.Schaumann S.Schumacher A.Tauschwitz D.varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major P.Neumayer D.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

Comparison of diode laser continuous wave and in soft tissue surgery using pulsed modes in vitro

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Frontiers of Optoelectronics 2015年第2期8卷 212-219页

作者： andrey v. belikov Alexei v. SKRYPNIK Ksenia v. SHATILOvA Saint-Petersburg National Research University of Information Technologies Mechanics and Optics (ITMO University) Saint-Petersburg 197101 Russia

In this study, the interaction between diode laser radiation and chicken soft tissue was studied in vitro by a high-speed digital video camera. We used a diode laser with a wavelength of （980 ±10）nm and average power of 10 W. The diode laser was operated in continuous wave （CW） and pulsed modes. In CW mode, the average laser radiation power was 10 W; in pulsed mode, the average laser radiation power was I0 W and the peak power was 20 W. Diode laser radiation was delivered to soft tissue （chicken meat） using a quartz optical fiber with either a clear distal end （clear tip） or a distal end containing an optothermal converter （hot tip）. Application of the diode laser in pulsed mode resulted in crater depths and areas of collateral damage in soft tissue about 1.6 times greater than those observed in CW mode at treatment with the clear tip. Significant differences in the crater depth and collateral damage width of chicken meat were not found after hot-tip treatment with the diode laser in CW and pulsed modes. Soft tissue treated with the hot tip showed crater depths about 3.4 times greater than those observed after treatment with the clear tip. Hot tip treatment further resulted in collateral damage widths about 2.7 times lower than those obtained after treatment with the clear tip.

关键词： diode laser thermo-optically powered sur-gery hot tip surgery laser surgery soft tissue

Regenerative medicine of pancreatic islets

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World Journal of Gastroenterology 2020年第22期26卷 2948-2966页

作者： Irina v Arutyunyan Timur Kh Fatkhudinov andrey v Makarov andrey v Elchaninov Gennady T Sukhikh National Medical Research Center for Obstetrics Gynecology and Perinatology named after Academician V.I.Kulakov of Ministry of Healthcare of Russian FederationMoscow 117997Russia Research Institute of Human Morphology Moscow 117418Russia Peoples Friendship University of Russia Moscow 117198Russia Pirogov Russian National Research Medical University Ministry of Healthcare of the Russian FederationMoscow 117997Russi

The pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly *** number of people living with diabetes mellitus is currently approaching half a billion,hence the crucial relevance of new methods to stimulate regeneration of the insulin-secretingβ-cells of the islets of *** restrictions on the islet regeneration are very tight;nevertheless,the islets are capable of physiological regeneration viaβ-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneousα-toβ-orδ-toβ-cell conversion(trans-differentiation).The existing preclinical models ofβ-cell dysfunction or ablation(induced surgically,chemically or genetically)have significantly expanded our understanding of reparative regeneration of the islets and possible ways of its *** ultimate goal,sufficient level of functional activity ofβ-cells or their substitutes can be achieved by two prospective broad strategies:β-cell replacement andβ-cell ***“regeneration”strategy aims to maintain a preserved population ofβ-cells through in situ exposure to biologically active substances that improveβ-cell survival,replication and insulin secretion,or to evoke the intrinsic adaptive mechanisms triggering the spontaneous non-β-toβ-cell ***“replacement”strategy implies transplantation ofβ-cells(as non-disintegrated pancreatic material or isolated donor islets)orβ-like cells obtained ex vivo from progenitors or mature somatic cells(for example,hepatocytes orα-cells)under the action of small-molecule inducers or by genetic *** believe that the huge volume of experimental and clinical studies will finally allow a safe and effective solution to a seemingly simple goal-restoration of the functionally activeβ-cells,the innermost hope of millions of people globally.

关键词： Pancreas Islets of langerhans β-cells Regeneration Replacement Transplantation Reprogramming

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

Autonomous UAv 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains

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Defence Technology（防务技术） 2023年第12期30卷 154-160页

作者： andrey v.Savkin Satish C.verma Wei Ni School of Electrical Engineering and Telecommunications University of New South WalesSydneyAustralia Data61 CSIROCanberraACT2601Australia

This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial vehicle(UAv),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data *** ground sensor model takes into account sensor data buffer and battery *** asymptotically globally optimal method of joint UAv 3D trajectory optimization and data transmission schedule is *** developed method maximizes the amount of data transmitted to the UAv without losses and too long delays and minimizes the propulsion energy of the *** developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic *** simulations demonstrate the effectiveness of the proposed algorithm.

关键词： Unmanned aerial system UAS Unmanned aerial vehicle UAv Wireless sensor networks UAS-Assisted data collection 3D trajectory optimization Data transmission scheduling