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BLOCKCHAiN-RESEARCH AND APPLiCATiONS 2024年第3期5卷 22-41页

作者： Buccafurri, Francesco De Angelis, Vincenzo Nardone, Roberto Univ Reggio Calabria I-89124 Reggio Di Calabria Italy Univ Calabria I-87036 Arcavacata di Rende CS Italy Univ Naples Parthenope I-80143 Naples Italy

The interest in Self-Sovereign identity (SSi) in research, industry, and governments is rapidly increasing. SSi is a paradigm where users hold their identity and credentials issued by authorized entities. SSi is revolutionizing the concept of digital identity and enabling the definition of a trust framework wherein a service provider (verifier) validates the claims presented by a user (holder) for accessing services. However, current SSi solutions primarily focus on the presentation and verification of claims, overlooking a dual aspect: ensuring that the verifier is authorized to access the holder's claims. Addressing this gap, this paper introduces an innovative SSi-based solution that integrates decentralized wallets with Ciphertext-Policy Attribute-Based Proxy Re-Encryption (CP-ABPRE). This combination effectively addresses the challenge of verifier authorization. Our solution, implemented on the Ethereum platform, enhances accountability by notarizing key operations through a smart contract. This paper also offers a prototype demonstrating the practicality of the proposed approach. Furthermore, it provides an extensive evaluation of the solution's performance, emphasizing its feasibility and efficiency in real-world applications.

关键词： Blockchain iPFS Self Sovereign identity Smart contract Access control PROXY RE-ENCRYPTiON SCHEME

interpolation of Vector Measures

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Acta Mathematica Sinica,English Series 2011年第1期27卷 119-134页

作者： Ricardo del CAMPO Antonio FERNANDEZ Fernando MAYORAL Francisco NARANJO Enrique A. SANCHEZ-PEREZ dpto. Matemdtica aplicada i Universidad de SevillaEUITA Ctra. de Utrera Kin. 1 41013 Sevilla Spain dpto. Matemdtica aplicada ii Universidad de Sevilla Escuela Tdcnica Superior de Ingenieros Camino de los Descubrimientos s/n 41092 Sevilla Spain instituto Universitario de Matemdtica Pura y aplicada Universidad Politdcnica de Valencia Camino de Vera s/n 46022 Valencia Spain

Let （Ω, ∑） be a measurable space and mo ： E→ Xo and m1 ： E → X1 be positive vector measures with values in the Banach KSthe function spaces Xo and X1. if 0 〈 a 〈 1, we define a X01-ax1a new vector measure [m0, m]a with values in the Calderdn lattice interpolation space and we analyze the space of integrable functions with respect to measure [m0, m1]a in order to prove suitable extensions of the classical Stein Weiss formulas that hold for the complex interpolation of LP-spaces. Since each p-convex order continuous Kothe function space with weak order unit can be represented as a space of p-integrable functions with respect to a vector measure, we provide in this way a technique to obtain representations of the corresponding complex interpolation spaces. As applications, we provide a Riesz-Thorin theorem for spaces of p-integrable functions with respect to vector measures and a formula for representing the interpolation of the injective tensor product of such spaces.

关键词： interpolation Banach function space vector measure

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： H.ASGHARi L.MiLLER R.PENTA J.MERODiO Departamento de Matematica aplicada a las TiC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic *** obtain the solution by performing a Laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain the solution in the Laplace transformed domain before reverting back to the time *** sensitivity analysis is then carried out,considering only the derived pressure *** analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis Laplace transform cylindrical polar coordinate Biot's modulus cylinder

ZrB_(2)-SiC ceramics toughened with oriented paper-derived graphite for a sustainable approach

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Journal of Advanced Ceramics 2024年第2期13卷 207-219页

作者： Luca Zoli Francesca Servadei Simone Failla Matteo Mor Antonio Vinci Pietro Galizia Diletta Sciti CNR-iSSMC Institute of ScienceTechnology and Sustainability for CeramicsFaenza I-48018Italy

Carbon fibre-reinforced ultra-high temperature ceramics(UHTCs)are considered a class of promising materials for several applications,the most appealing ones being in the aerospace *** is necessary to overcome the brittleness and low thermal shock resistance of ceramics and is often provided through the addition of carbon fibres or other carbon-based phases,such as nanotubes,graphene,and *** present work is focused on the toughening of UHTCs through incorporation of 30-50 vol% thin,ordered graphite layers from conventional filter paper followed by hot pressing *** filter paper was selected because it undergoes thermolysis with no melting stage forming a strong carbonaceous residue that can be used as *** and mechanical properties of toughened composites were compared to those of other materials reinforced with short carbon fibres and the effect of different distribution of graphite was *** of graphite allowed toughness to be increased from 3−4 MPa·m^(1/2)(for unreinforced materials)to 5.1−5.5 MPa·m^(1/2),similar to results obtained with short fibre *** high-temperature properties,such as strength and toughness as well as oxidation resistance at 1500℃,were also examined.

关键词： borides paper-derived graphite microstructure toughness sustainability

Transmission of amyloid-βpathology in humans:a perspective on clinical evidence

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Neural Regeneration Research 2024年第2期19卷 390-392页

作者： Celso S.G.Catumbela Rodrigo Morales Department of Neurology McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Centro integrativo de Biologia y Quimica aplicada(CiBQA) Universidad Bernardo O’HigginsSantiagoChile

Transmission of misfolded amyloid-β(Aβ)aggregates between human subjects:Protein misfolding disorders are a family of diseases characterized by the accumulation of misfolded protein *** proteinaceous structures,also known as amyloids,are key drivers of fatal neurodegenerative disorders such as prion diseases,Alzheimer’s disease(AD),Parkinson’s disease,and others.

关键词： amyloid diseases Aβ

A multi-shot target wheel assembly for high-repetition-rate, laser-driven proton acceleration

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High Power Laser Science and Engineering 2024年第2期12卷 87-94页

作者： J.Penas A.Bembibre D.Cortina-Gil L.Martin A.Reija C.Ruiz M.Seimetz A.Alejo J.Benlliure instituto Galego de fisica de Altas Enerxias Universidade de Santiago de CompostelaSantiago de CompostelaSpain Laboratorio Laser de Aceleracion y Aplicaciones RIAIDTUniversidade de Santiago de CompostelaSantiago de CompostelaSpain instituto Universitario de Física Fundamental y Matematicas y dpto.de Didactica de la Matematica y de las Ciencias Experimentales Universidad de SalamancaSalamancaSpain instituto de instrumentación para imagen Molecular(i3M) CSIC-Universitat Politecnica de ValenciaValenciaSpain

A multi-shot target assembly and automatic alignment procedure for laser–plasma proton acceleration at high repetition rate are *** assembly is based on a multi-target rotating wheel capable of hosting more than 5000 targets,mounted on a 3D motorized stage to allow rapid replenishment and alignment of the target material between laser *** automatic alignment procedure consists of a detailed mapping of the impact positions at the target surface prior to the irradiation that ensures stable operation of the target,which alongside the purpose-built design of the target wheel,enables operation at rates up to 10 *** and continuous laser-driven proton acceleration at 10 Hz is demonstrated,with observed cut-off energy stability about 15%.

关键词： high repetition rate laser-plasma acceleration multi-shot operation proton source target assembly

A Protocol for Fractal Studies on Porosity of Porous Media: High Quality Soil Porosity images

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Journal of Earth Science 2017年第5期28卷 888-896页

作者： Carlos García-Gutiérrez Fernando San José Martínez J.Caniego dpto.Matemática aplicada E.T.S.I.Navales Universidad Politécnica de Madrid dpto.Matemática aplicada E.T.S.I.Agrónomos Universidad Politécnica de Madrid

A protocol for obtaining digital images from natural porous media with a wide range of pore sizes, intended for fractal studies of the porosity, is proposed. Soil porosity is used as para- digm of complex natural porous media in this study. The use of several imaging devices and fluores- cent compounds to enhance the contrast between the solid and the pore phase is tested. Finally a protocol is reached using a photo camera and a confocal microscope. it is the first time that confocal microscopy is used for this purpose. Artificial porous images are created through random Sierpinski carpet fractals and the statistical information of real soil images. These ground truth images are used in an objective comparison of automatic segmentation algorithms for the obtained images. A statistical classification on the performance of several automatic segmentation algorithms for this tv^e of images is reached.

关键词： porous media micromorphology image segmentation confocal microscope fractal,porosity photography.

Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at Extremes 2024年第3期9卷 31-44页

作者： M.R.D.Rodrigues A.Bonasera M.Scisciò J.A.Pérez-Hernández M.Ehret F.Filippi P.L.Andreoli M.Huault H.Larreur D.Singappuli D.Molloy D.Raffestin M.Alonzo G.G.Rapisarda D.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.McNamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.Di Giorgio G.Cristofari R.De Angelis G.A.P.Cirrone D.Margarone L.Giuffrida D.Batani P.Nicolai K.Batani R.Lera L.Volpe D.Giulietti S.Agarwal M.Krupka S.Singh Fa.Consoli Cyclotron institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly ENEA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers intenses et Applications(CELiA) Universitéde BordeauxCNRSCEATalenceFrance HB11 Energy Holdings Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom Dipartimento di fisica e Astronomia“E.Majorana ”Università di CataniaCataniaItaly Facoltàdi ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly Dipartimento di ingegneria industriale Universitàdi Roma“Tor Vergata”RomaItaly Dipartimento di fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly istituto Nazionale di fisica Nucleare Sezione di PerugiaPerugiaItaly ELi Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic ETSiA Universidad Politécnica de MadridMadridSpain Dipartimento fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–institute of Physics of Czech Academy of Sciences PragueCzech Republic institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Continuously non-malleable codes from block ciphers in split-state model

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Cybersecurity 2024年第2期7卷 68-80页

作者： Anit Kumar Ghosal Dipanwita Roychowdhury Department of Computer Science and Engineering I KharagpurKharagpurWest BengalIndia

Non-malleable code is an encoding scheme that is useful in situations where traditional error correction or detection is impossible to *** ensures with high probability that decoded message is either completely unrelated or the original one,when tampering has no ***,standard version of non-malleable codes provide security against one time tampering *** ciphers are successfully employed in the construction of non-malleable *** construction fails to provide security when an adversary tampers the codeword more than *** non-malleable codes further allow an attacker to tamper the message for polynomial number of *** this work,we propose continuous version of non-malleable codes from block ciphers in split-state *** construction provides security against polynomial number of tampering attacks and it preserves *** the tam-pering experiment triggers self-destruct,the security of continuously non-malleable code reduces to security of the underlying leakage resilient storage.

关键词： Block cipher Non-malleable code Split-state model Tamper-resilient cryptography

Optimal orbit transfer of single-tether E-sail with inertially fixed spin axis

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Astrodynamics 2024年第2期8卷 285-295页

作者： Alessandro A.Quarta Marco Bassetto Giovanni Mengali Department of Civil and industrial Engineering University of PisaPisa I-56122Italy

This study analyzes the optimal transfer trajectory of a spacecraft propelled by a spinstabilized electric solar wind sail(E-sail)with a single conducting tether and a spin axis with a fixed direction in an inertial(heliocentric)reference *** approach proposed in this study is useful for rapidly analyzing the optimal transfer trajectories of the current generation of small spacecraft designed to obtain in-situ evidence of the E-sail propulsion *** this context,starting with the recently proposed thrust model for a single-tether E-sail,this study discusses the optimal control law and performance in a typical two-dimensional interplanetary transfer by considering the(binary)state of the onboard electron emitter as the single control *** resulting spacecraft heliocentric trajectory is a succession of Keplerian arcs alternated with propelled arcs,that is,the phases in which the electron emitter is switched *** particular,numerical simulations demonstrated that a single-tether E-sail with an inertially fixed spin axis can perform a classical mission scenario as a circle-to-circle two-dimensional transfer by suitably varying a single control parameter.

关键词： electric solar wind sail(E-sail) single conducting tether fixed inertial spin axis trajectory optimization circle-to-circle coplanar transfer