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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 Engineering University of Kashan

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures, flexibility, and attractive appearance. However, the inability of controlling and regulating vibrations and destroying them afterward is a challenge to scientists. In 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 theory. The core(honeycomb, truss, and corrugated) is analyzed for the bearing of transverse shear forces. The results show that the honeycomb core has a greater effect on the vibrations. When the parameters related to the core and the weight percentage of graphene increase, the frequency increases. The uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency increases. furthermore, without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT) and fourth-order shear deformation theory(fOSDT) align closely. However, 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： 74f15 corrugate core doubly curved shell honeycomb micro-composite O343 truss vibration and control

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

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

morphological traits explain the individual position within resource-consumer networks of a Neotropical marsupial

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Current Zoology 2024年第4期70卷 453-464页

作者： Nicholas f.de Camargo Hernani f.m.de Oliveira Juliana f.Ribeiro Amabilio J.A.de Camargo Emerson m.Vieira Laboratorio de Ecologia de Vertebrados Departamento de EcologiaInstituto de Ciencias BiologicasUniversidade de BrasiliaCP 04457BrasiliaDF70910-900Brazil Departamento de Zoologia Setor de Ciencias BiologicasUniversidade Federal do ParanaAvenida Coronel Francisco Heraclito dos Santos100CuritibaPR81531980Brazil Embrapa Cerrados Rodovia BR020km 18CP 08223PlanaltinaDE73310-970Brazil

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation *** tested hypotheses on the relationships between individuals'positions within networks(specialization and centrality)of 4 populations of the mouse opossum Gracilinanus agilis and their traits(i.e.,body length,body condition,tail length relative to body length,sex,reproductive condition,and botfly parasitism)and also seasonal effects in the Brazilian *** with lower body length,better body condition,and relatively shorter tail were more specialized(i.e.,less connected within the network).Individuals were also more specialized and less connected during the warm-wet *** relationship between individuals'position in the network and body traits,however,was independent of *** propose that specialization may arise not only as a result of preferred feed-ing strategies by more capable individuals(i.e.,those with better body condition and potentially prone to defend and access high-quality food resources)but alsobecause of morphological ***/younger individuals(consequently with less experience in foraging)and short-tailed individuals(less skilled to explore the vertical strata of the vegetation)would feed only on a subset of the available food resources and consequently become more ***,individuals are more specialized during the warm-wet season because of high competition(population-dense period)and higher ecological opportunities(resource-rich period).Therefore,our study reveals the relevance of individual traits inshaping interactionpatternsandspecialization inpopulations.

关键词： bodytraits centrality Cerrado Gracilinanus agilis seasonality specialization.

A review of ethnobotanical studies reveals over 500 medicinal plants in mindanao,Philippines

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Plant Diversity 2024年第5期46卷 551-564页

作者： Joeime f.meñiza monica m.Pasco Jemer A.Alimbon Department of Teacher Education UM Tagum CollegeTagum City8100Davao del Norte Philippines

medicinal plants have long been used to treat various diseases in both indigenous and non-indigenous populations of mindanao,***,we extracted data from ethnobotanical studies to compile a comprehensive list of these medicinal plants and identify how and for what purpose they are most commonly *** identified 530 verified medicinal plant species across 372 genera in 118 *** two most frequently cited species were Euphorbia hirta and Psidium *** most represented family was fabaceae and the most represented genus was ficus.A total of 28 medicinal plant species are designated as threatened at the national or global level;of these,11 are endemic to the *** plant preparations most commonly use leaves for oral administration to treat various diseases such as digestive issues,including *** study underscores the need for further ethnobotanical investigations,particularly in areas lacking *** also emphasizes the need for conservation of threatened and endemic medicinal plants to ensure sustainable utilization of this valuable resource.

关键词： Ethnobotany medicinal plants mindanao Philippines

Carbon monoxide as C1 Building Block in fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.f.Calvete Gabor mikle Laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide fine chemicals Carbonylation Hydroformylation C-H functionalization

Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.m.Gillies E.Spanswick E.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.f.Darwish mohamed H.A.Hassan Nagat m.K.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturefted especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by fourier transform infrared(fTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the fTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDf)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila m.Halman mohammed J.f.Alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and *** this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human *** can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or *** this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS *** then evaluate the accuracy and performance of the proposed TBDC *** technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare