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Non-adhesive and adhesive contacts of an elastic quarter-or eighth-space with freely sliding sides

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Friction 2024年第9期12卷 2052-2063页

作者： Qiang Li Valentin L.popov Technische Universität Berlin Berlin 10623Germany

The contact of an elastic quarter-or eighth-space is studied under the condition that the movement of the side surface of the quarter-space is constrained:it can slide freely along the plane of the side surface but its normal movement is blocked(for example,by a rigid wall).The solution of this contact problem can be easily achieved by additionally applying a mirrored load to an elastic ***-adhesive contact and the Johnson–Kendall–Roberts(JKR)-type adhesive contact between a rigid sphere and an elastic quarter-space under such a boundary condition is numerically simulated using the fast Fourier transform(FFT)-assisted boundary element method(BEM).Contacts of an elastic eighth-space are investigated using the same *** on the position of the sphere relative to the side edge,different contact behavior is *** the case of adhesive contact,the force of adhesion first increases with increasing the distance from the edge of the quarter-space,achieves a maximum,and decreases further to the JKR-value in large distance from the *** enhancement of the force of adhesion compared to the half-space-contact is associated with the pinning of the contact area at the *** provide the maps of the force of adhesion and their analytical approximations,as well as pressure distributions in the contact plane and inside the quarter-/eighth-space.

关键词： quarter-space eighth-space adhesion edge effect boundary element method(BEM)

Approximate contact solutions for non-axisymmetric homogeneous and power-law graded elastic bodies:A practical tool for design engineers and tribologists

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Friction 2024年第2期12卷 340-355页

作者： Valentin L.popov Qiang Li Emanuel WiLLERT institute of Mechanics Technische Universität BerlinBerlin 10623Germany

in two recent papers,approximate solutions for compact non-axisymmetric contact problems of homogeneous and power-law graded elastic bodies have been suggested,which provide explicit analytical relations for the force–approach relation,the size and the shape of the contact area,as well as for the pressure distribution *** solutions were derived for profiles,which only slightly deviate from the axisymmetric *** the present paper,they undergo an extensive testing and validation by comparison of solutions with a great variety of profile shapes with numerical solutions obtained by the fast Fourier transform(FFT)-assisted boundary element method(BEM).Examples are given with quite significant deviations from axial symmetry and show surprisingly good agreement with numerical solutions.

关键词： normal contact non-axisymmetric indenter extremal principle generalized method of dimensionality reduction(MDR) functional elastic grading

improved organs at risk segmentation based on modified U‐Net with self‐attention and consistency regularisation

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CAAi Transactions on intelligence Technology 2024年第4期9卷 850-865页

作者： Maksym Manko Anton popov Juan Manuel Gorriz Javier Ramirez Electronic Engineering Department Igor Sikorsky Kyiv Polytechnic InstituteKyivUkraine Department of Signal Theory Telematics and CommunicationsUniversity of GranadaGranadaSpain

Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment *** planning starts with delineating the affected area from healthy organs,called organs at risk(OAR).A new approach to automatic OAR seg-mentation in the chest cavity in Computed Tomography(CT)images is *** proposed approach is based on the modified U‐Net architecture with the ResNet‐34 encoder,which is the baseline adopted in this *** new two‐branch CS‐SA U‐Net architecture is proposed,which consists of two parallel U‐Net models in which self‐attention blocks with cosine similarity as query‐key similarity function(CS‐SA)blocks are inserted between the encoder and decoder,which enabled the use of con-sistency *** proposed solution demonstrates state‐of‐the‐art performance for the problem of OAR segmentation in CT images on the publicly available SegTHOR benchmark dataset in terms of a Dice coefficient(oesophagus-0.8714,heart-0.9516,trachea-0.9286,aorta-0.9510)and Hausdorff distance(oesophagus-0.2541,heart-0.1514,trachea-0.1722,aorta-0.1114)and significantly outperforms the *** current approach is demonstrated to be viable for improving the quality of OAR segmentation for radiotherapy planning.

关键词： 3‐D computer vision deep learning deep neural networks image segmentation medical image processing object segmentation

Physiological strategies in wild rodents:immune defenses of commensal rats

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integrative Zoology 2024年第3期19卷 350-370页

作者： ivana MiRKOV Dina TUCOViC Jelena KULAS Anastasija MALESEViC Dragan KATARANOVSKi Milena KATARANOVSKi Aleksandra popov ALEKSANDROV immunotoxicology Group Department of EcologyInstitute for Biological Research“Sinisa Stankovic”—National Institute of Republic of SerbiaUniversity of BelgradeBelgradeSerbia

The importance of issues associated with urban/commensal rats and mice(property damage,management costs,and health risks)press upon research on these *** the demography of commensal rodents is mostly studied,the need for understanding factors influencing their natural morbidity/mortality is also *** this respect,more attention is expected to be paid to immunity,the physiological mechanism of defense against host survival threats(pathogens,parasites,diseases).Commensal rats and mice carry numerous pathogens that evoke diverse immune *** state of immunity in commensal house mice is studied in great detail,owing to the use of laboratory strains in biomedical *** commensal rats are,compared to mice,carriers of more zoonotic agents,rats’immunity is studied mainly in that *** of these zoonotic agents cause chronic,asymptomatic infections,which justified studies of immunological mechanisms of pathogen tolerance versus clearance regulation in *** of some infections in specific tissues/organs pressed upon analysis of local/regional immune responses and/or immunopathology.A survey of immunological activity/responses in commensal rats is given in this review,with mention of existing data in commensal *** should throw some light on the factors relevant to their morbidity and lifespan,supplementing the knowledge of commensal rodent ecology.

关键词： commensal rats and mice immunopathology infection inflammation tolerance

Security and Privacy Challenges in SDN-Enabled ioT Systems: Causes, Proposed Solutions,and Future Directions

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Computers, Materials & Continua 2024年第8期80卷 2511-2533页

作者： Ahmad Rahdari Ahmad Jalili Mehdi Esnaashari Mehdi Gheisari Alisa A.Vorobeva Zhaoxi Fang Panjun Sun Viktoriia M.Korzhuk ilya popov Zongda Wu Hamid Tahaei institute of Artificial intelligence Shaoxing UniversityShaoxing312000China Department of Computer Engineering Gonbad Kavous UniversityGonbad-e Kavus49717-99151Iran Faculty of Computer Engineering K.N.Toosi University of TechnologyTehran196976-4499Iran Department of Computer Science and Engineering Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennai602105India Secure information Technologies Department National Research University ITMOSt.Petersburg197101Russia School of Electrical and Computer Engineering Shiraz UniversityShiraz71946–84334Iran Department of Computer Science and Engineering Islamic Azad UniversityDamavand***Iran Department of R&D Shenzhen BKD Co.Ltd.Shenzhen518000China

Software-Defined Networking(SDN)represents a significant paradigm shift in network architecture,separating network logic from the underlying forwarding devices to enhance flexibility and centralize ***-rently,the internet of Things(ioT)connects numerous devices to the internet,enabling autonomous interactions with minimal human ***,implementing and managing an SDN-ioT system is inherently complex,particularly for those with limited resources,as the dynamic and distributed nature of ioT infrastructures creates security and privacy challenges during SDN *** findings of this study underscore the primary security and privacy challenges across application,control,and data planes.A comprehensive review evaluates the root causes of these challenges and the defense techniques employed in prior works to establish sufficient secrecy and privacy *** investigations have explored cutting-edge methods,such as leveraging blockchain for transaction recording to enhance security and privacy,along with applying machine learning and deep learning approaches to identify and mitigate the impacts of Denial of Service(DoS)and Distributed DoS(DDoS)***,the analysis indicates that encryption and hashing techniques are prevalent in the data plane,whereas access control and certificate authorization are prominently considered in the control plane,and authentication is commonly employed within the application ***,this paper outlines future directions,offering insights into potential strategies and technological advancements aimed at fostering a more secure and privacy-conscious SDN-based ioT ecosystem.

关键词： Security privacy-preserving software-defined network internet of things

Atherosclerosis originating from childhood:Specific features

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Journal of Biomedical Research 2024年第3期38卷 233-240页

作者： Anastasia V.Poznyak Alexey A.yakovlev MikhailА.popov Elena B.Zhigmitova Vasily N.Sukhorukov Alexander N.Orekhov institute for Atherosclerosis Research Moscow 121609Russia Federal Research and Clinical Center of intensive Care Medicine and Rehabilitology Moscow 109240Russia Department of Cardiac Surgery Moscow Regional Research and Clinical InstituteMoscow 129110Russia Laboratory of Angiopathology Institute of General Pathology and PathophysiologyMoscow 125315Russia

Atherosclerosis is extremely ***,it is considered a disease of older people,who most often experience problems with the heart and blood *** much attention from the scientific community has been paid to studying the association between aging and atherosclerosis,as well as its consequences,there is evidence that atherosclerosis occurs at an early *** may form both during intrauterine development and in *** plays an important role in childhood atherosclerosis,along with previous infectious diseases and excess weight of both the child and the *** the present review,we examined the development of atherosclerosis and the prerequisites in childhood.

关键词： atherosclerosis childhood pediatrics cardiovascular disease

Prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： R.S.Mukhin A.V.isaev A.V.Andreev M.L.Chelnokov V.i.Chepigin H.M.Devaraja i.N.izosimov A.A.Kuznetsova O.N.Malyshev A.G.Popeko yu.A.popov A.Rahmatinejad B.Sailaubekov T.M.Shneidman E.A.Sokol A.i.Svirikhin M.S.Tezekbayeva M.A.Bychkov A.V.yeremin O.Dorvaux B.Gall K.Kessaci K.Hauschild A.Lopez-Martens Joint institute for Nuclear Research Dubna141980Russia Dubna State University Dubna141982Russia institute of Nuclear Physics Almaty050032Kazakhstan L.N.Gumilyov Eurasian National University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France iJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the SFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

High-performance portable grating-based surface plasmon resonance sensor using a tunable laser at normal incidence

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Photonics Research 2024年第5期12卷 947-958页

作者： DUC LE ANNi RANTA-LASSiLA TEEMU SiPOLA MiKKO KARPPiNEN JARNO PETAJA MiNNA KEHUSMAA SANNA AiKiO TiAN-LONG GUO MATTHiEU ROUSSEy JUSSi HiLTUNEN ALEXEy popov VTT Technical Research Centre of Finland 90570 OuluFinland Department of Physics and Mathematics University of Eastern FinlandFI-80101 JoensuuFinland

Surface plasmon resonance(SPR)sensors are among the most sensitive *** such devices,a grating is a compelling alternative to a prism for the excitation of a surface plasmon,especially in the development of sensors for point-of-care applications due to their compactness and ***,we demonstrate the use of a tunable laser in a grating-based SPR system for further miniaturization and *** tunable laser working at normal incidence replaces spectral and moving components,while also simplifying the optical *** incidence is conventionally avoided due to the complexity of the control of degenerated SPR *** investigate,both computationally and experimentally,the splitting of the SPR modes at small nonzero incidences,which is lacking in previously reported *** optimizing the grating configuration,we were able to diminish the SPR mode splitting phenomenon when the excitation was feasible with the normal incidence *** fabricated sensor showed a high sensitivity of 1101.6 nm/***,the figure of merit of the sensor,defined as the ratio between the sensitivity and bandwidth of the SPR dip,was *** experimental results were consistent with the simulation *** also demonstrate its capability for detecting low concentrations of glucose and creatinine with the limit of detection of 14.2 and 19.1 mmol/L,respectively.

关键词： tunable splitting excitation

Model of tunnelling through periodic array of quantum dots in a magnetic field

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Chinese Physics B 2012年第11期21卷 412-415页

作者： i.yu.popov S.A.Osipov St.Petersburg National Research University of information Technologies Mechanics and OpticsKronverkskiy49St.Petersburg 197101Russia

A two-dimensional periodic array of quantum dots with two laterally coupled leads in a magnetic field is considered. The model of electron transport through the system based on the theory of self-adjoint extensions of symmetric operators is suggested. We obtain the formula for the transmission coefficient and investigate its dependence on the magnetic field.

关键词： tunnelling nanostructure operator extension theory