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天文研究与技术 1989年第4期 78-81页

作者：吴光节 m.f.埃亨云南天文台美国马里兰大学物理天文系

本文介绍了利用计算机产生给定误差分布的模拟随机样品的一种方法。

关键词：给定误差随机数发生器随机采样泊松分布随机变量高斯分布谱线轮廓确定模型采样点高斯型

一种评估非接触水下爆炸对海军复合船体影响的设计方法

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 316-326页

作者： f.mannacio f.Di marzo m.Gaiotti C.m.Rizzo m.Venturini Italian Navy Naval Support and Experimentation CentreCSSN Viale S.Bartolomeo40019126 La Spezia(Italy) University of Genova Polytechnic SchoolDITEN Via Montallegro116145 Genova(Italy).

Despite the non-contact underwater explosion phenomena(UNDEX)have been studied for decades and several numerical methods have been proposed in literature,its effects on military structures,especially composite ones,are even nowadays matter of *** early design phases,it is not always possible to verify the shock resistance of hull structures modelling the whole phenomenon,in which fluid,gas and solid properties must be properly set in a fully coupled fluid-structure interaction(fSI)numerical *** ones are extremely complex to set,computationally demanding and certainly not suitable for everyday design *** this paper,a simplified finite element(fE)model,easy to use in an early design phase,is ***,the structure and the fluid are *** this approximation,the fluid behaviour is simplified,using special finite elements,available in a commercial software *** choice reduces the computational time and numerical efforts avoiding the problem of combining computational fluid dynamics(CfD)and fE domains and equations in a fully coupled fluid-structure interaction model.A typical parallel body block of a minesweeper is modelled,using two-dimensional multi-layered shell elements to properly account for the composite materials *** the fluid instead,three dimensional volumetric elements,directly coupled to the structural elements,are *** addition,the same calculation is performed,modelling separately fluid in the CfD environment and structures in the finite element ***,realizing a fully coupled fluid-structure interaction *** results obtained by applying both numerical models are compared with the structural response measured on board of a composite ship during a full-scale shock *** simplified proposed procedure provides results in satisfactory agreement with experiments,allowing the validation of the *** are discussed and differences with the real phenomenon and fully coupled CfD+

关键词： Underwater explosions Shock resistance Composites fluid-structure interaction Experimental analysis Numerical simulation Vulnerability Preliminary design

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied mathematics and mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN m.mOHAmmADImEHR f.BARGOZINI Department of Solid mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

miniSCIDOm: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino m.Reimold E.Beyreuther f.-E.Brack f.Kroll J.Pawelke J.D.Schilz m.Schneider U.Schramm m.E.P.Umlandt K.Zeil T.Ziegler J.metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum.f.eiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOm detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 711-724页

作者： f.JAZINI DORCHEH m.GHASSEmI fuel Cells and Nano Systems(fCNS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.marquès L.Lancia P.Loiseau P.forestier-Colleoni m.Tarisien E.Atukpor V.Bagnoud C.Brabetz f.Consoli J.Domange f.Hannachi P.Nicolaï m.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum.f.r Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

Langmuir-Schaefer film Investigation and Density functional Theory Band Gap Calculations of Calix[n]arene-Para-Aminobenzoic Acid for Drug Nanosensor Application

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Journal of Wuhan University of Technology(materials Science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong Yi f L Supian A Radzwan m musa N f N Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DfT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),fourier-transform infrared spectroscopy(fTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DfT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther N.Bukharskii N.Borisenko J.Jacoby X.f.Shen A.Pukhov N.E.Andreev O.N.Rosmej faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum.f.r Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an fWHm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

促进慢性阻塞性肺疾病哮喘患者自我监控空气质量的护理干预措施: 整合性综述

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International Journal of Nursing Sciences 2024年第1期11卷 46-56页

作者： Bruna f.Sebastiao Raquel m.Hortelao Sara S.Granadas Jose m.f.ria Joana R.Pinto Helga Rafael Henriques Nursing School of Lisbon LisbonPortugal Hospital Center of Central Lisbon Portugal CUf Tejo Hospital LisbonPortugal University Hospital Center of Northern Lisbon LisbonPortugal Nursing Research Innovation and Development Centre of Lisbon(CIDNUR)LisbonPortugal

目的哮喘-慢性阻塞性肺疾病肺重叠症(Asthma-chronie obst ructive pulmonary disease overlap,A-CO)患者的生活质量较低,肺功能较差,病情经常加重。由于暴露于污染环境会加重其症状,增加发病率和病死率,环境管理对其至关重要。旨在通... 详细信息

目的哮喘-慢性阻塞性肺疾病肺重叠症(Asthma-chronie obst ructive pulmonary disease overlap,A-CO)患者的生活质量较低,肺功能较差,病情经常加重。由于暴露于污染环境会加重其症状,增加发病率和病死率,环境管理对其至关重要。旨在通过系统性综述,寻找证据,以指导制订护理干预措施,促进ACO患者对空气质量的自我管理。方法2023年3月 ,系统检索CINAHL、medline、Academie Search Complete .Scopus、WebofScience、Cochrane图书馆、乔安娜布里格斯研究所(JoannaBriggsInstitute,JBI)循证实践数据库,以及GoogleScholar。对纳人研究进行数据提取和综合,并对护理干预措施进行分类。采用JBI研究质量评估工具进行方法学质量评估。结果共纳入5篇来自不同国家的研究。促进ACO患者自我监控空气质量的干预措施包括:警觉性干预措施(医务人员定期巡诊、进行症状评估),监测干预措施(监测室内外诱发因素) ,教育干预措施(空气质量警报、避免接触过敏原),以及相关政策的影响,如无烟政策和改善空气质量的综合战略。尽管这些研究报告了不同的干预措施,方法质量也存在差异,但这些干预措施显示了预防患者病情恶化、尽量减少急诊就诊和住院治疗的潜力。这些关键点可作为护理干预措施的关键组成部分。结论有必要采取全面措施,让护士参与促进患者自我监控空气质量的多学科团队.提高认识、制订和实施护理干预,从而使ACO患者受益。同时,需要进--步开展研究,以扩大证据基础并完善这些干预措施。

关键词：空气质量哮喘哮喘-慢阻肺重叠慢性病慢性阻塞性肺疾病护理自我管理

Cyber Security within Smart Cities: A Comprehensive Study and a Novel Intrusion Detection-Based Approach

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Computers, materials and Continua 2024年第1期81卷 393-441页

作者： Houichi m. Jaidi f. Bouhoula A. University of Carthage Higher School of Communication of Tunis (Sup’Com) Innov’Com Lab\Digital Security Research Lab Tunis 2083 Tunisia National School of Engineers of Carthage University of Carthage Tunis 2035 Tunisia Department of Next-Generation Computing College of Graduate Studies Arabian Gulf University Manama 26671 Bahrain

The expansion of smart cities, facilitated by digital communications, has resulted in an enhancement of the quality of life and satisfaction among residents. The Internet of Things (IoT) continually generates vast amounts of data, which is subsequently analyzed to offer services to residents. The growth and development of IoT have given rise to a new paradigm. A smart city possesses the ability to consistently monitor and utilize the physical environment, providing intelligent services such as energy, transportation, healthcare, and entertainment for both residents and visitors. Research on the security and privacy of smart cities is increasingly prevalent. These studies highlight the cybersecurity risks and the challenges faced by smart city infrastructure in handling and managing personal data. To effectively uphold individuals’ security and privacy, developers of smart cities must earn the trust of the public. In this article, we delve into the realms of privacy and security within smart city applications. Our comprehensive study commences by introducing architecture and various applications tailored to smart cities. Then, concerns surrounding security and privacy within these applications are thoroughly explored subsequently. following that, we delve into several research endeavors dedicated to addressing security and privacy issues within smart city applications. finally, we emphasize our methodology and present a case study illustrating privacy and security in smart city contexts. Our proposal consists of defining an Artificial Intelligence (AI) based framework that allows: Thoroughly documenting penetration attempts and cyberattacks; promptly detecting any deviations from security standards; monitoring malicious behaviors and accurately tracing their sources; and establishing strong controls to effectively repel and prevent such threats. Experimental results using the Edge-IIoTset (Edge Industrial Internet of Things Security Evaluation Test) dataset demonstra

关键词： cybersecurity digital communications intrusion detection privacy Smart cities