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A critical literature review of security and privacy in smart home healthcare schemes adopting IoT&blockchain:Problems,challenges and solutions

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Blockchain(Research and Applications) 2024年第2期5卷 13-61页

作者： Olusogo Popoola Marcos Rodrigues Jims Marchang Alex Shenfield Augustine Ikpehai Jumoke Popoola Department of Computing Sheffield Hallam UniversitySheffieldS11WBUK Department of Engineering and Math Sheffield Hallam UniversitySheffieldS11WBUK

Protecting private data in smart homes,a popular Internet-of-Things(IoT)application,remains a significant data security and privacy challenge due to the large-scale development and distributed nature of IoT ***,smart healthcare has leveraged smart home systems,thereby compounding security concerns in terms of the confidentiality of sensitive and private data and by extension the privacy of the data ***,proof-of-authority(PoA)-based blockchain distributed ledger technology(DLT)has emerged as a promising solution for protecting private data from indiscriminate use and thereby preserving the privacy of individuals residing in IoT-enabled smart *** review elicits some concerns,issues,and problems that have hindered the adoption of blockchain and IoT(BCoT)in some domains and suggests requisite solutions using the aging-in-place *** issues with BCoT were examined as well as the combined challenges BCoT can pose when utilised for security *** study discusses recent findings,opportunities,and barriers,and provides recommendations that could facilitate the continuous growth of blockchain applications in ***,the study explored the potential of using a PoA-based permission blockchain with an applicable consent-based privacy model for decision-making in the information disclosure process,including the use of publisher-subscriber contracts for fine-grained access control to ensure secure data processing and sharing,as well as ethical trust in personal information disclosure,as a solution *** proposed authorisation framework could guarantee data ownership,conditional access management,scalable and tamper-proof data storage,and a more resilient system against threat models such as interception and insider attacks.

关键词： IoT Smart home healthcare PoA-based permissioned blockchain Authorisation framework Fine-grained access control Interception Privacy model Consent

Development of bismuth-based solutions for well plugging and abandonment:A review

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Petroleum Research 2024年第2期9卷 250-264页

作者： Lewaa Hmadeh Marcelo Anunciação Jaculli Behzad Elahifar Sigbjørn Sangesland Norwegian University of Science and Technology PTSValgrindaS.P.Andersens veg 15 ANorway

Plugging and abandonment(P&A)is a crucial step of the well life *** of how long one stretches the productive life of a well,P&A operations will have to be carried out *** current panorama of our industry includes many wells to be plugged and abandoned,with steep requirements to abide by both regulations and societal *** this context,we must guarantee that no leakage occurs with an eternal perspective in *** has been the prime material for this task,but recent studies have indicated the potential of degradation over time-especially in corrosive environments-and the creation of leaking paths due to its *** has opened up a path toward the usage of alternative *** of the emerging candidates is bismuth,a metal with the unique characteristic of expanding when *** a trait could improve the overall sealability of wellbores and especially during P&*** article discusses the current status of bismuth sealing technologies,introducing the basics of bismuth,the ongoing efforts to qualify it as a barrier material,its potential applications,and the challenges that still need to be *** latest research indicates promising results in terms of its usage as a barrier element.

关键词： Bismuth plugs Bismuth-tin alloys Well plugging and abandonment Well integrity

Solar wind ion charge state distributions and compound cross sections for solar wind charge exchange X-ray emission

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Earth and Planetary Physics 2024年第1期8卷 105-118页

作者： Dimitra Koutroumpa LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance

Solar Wind Charge eXchange X-ray(SWCX) emission in the heliosphere and Ea rth’s exosphere is a hard to avoid signal in soft Xray obse rvations of astrophysical *** the other hand,the X-ray imaging possibilities offered by the SWCX process has led to an increasing number of future dedicated space missions for investigating the solar wind-terrestrial inte ractions and magnetospheric *** both cases,accurate modelling of the SWCX emission is key to correctly interpret its signal,and remove it from obse rvations,when *** this paper,we compile solar wind abundance measurements from ACE for different solar wind types,and atomic data from literature,including charge exchange cross-sections and emission probabilities,used fo r calculating the compound cross-section a for the SWCX X-ray *** calculate a values for charge-exchange with H and He,relevant to soft X-ray energy bands(0.1-2.0 keV)for various solar wind types and solar cycle conditions.

关键词： solar wind charge exchange X-rays magnetosphere heliosphere

An Experimental Study on Response and Control of a Flapping-Wing Aerial Robot Under Wind Gusts

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Journal of Bionic Engineering 2024年第1期21卷 209-223页

作者： Kazuki Shimura Hikaru Aono Chang-kwon Kang Graduate School of Science and Technology Shinshu University3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical Engineering and Robotics 3-15-1 TokidaUedaNagano 3868567Japan Department of Mechanical and Aerospace Engineering University of Alabama in HuntsvilleTechnology Hall N266HuntsvilleAL35899USA

Bioinspired flapping-wing micro-air-vehicles(FWMAVs)have the potential to be useful aerial tools for gathering information in various *** recent advancements in manufacturing technologies and better understanding of aerodynamic mechanisms behind of the flapping flight,outdoor flights have become a ***,to fully realize the potential of FWMAVs,further improvements are necessary,particularly in terms of stability and robustness under gusty *** this study,the response and control of a tailless two-winged FWMAV under the wind gusts are *** experiments are conducted with a one-degree-of-freedom gimbal to focus on effects of wind gusts on the rotational motion of the ***-derivative and sliding-mode controls are adopted for the attitude *** present that the body angles changed in time and reached approximately 50°at the maximum due to the wing *** sliding-mode controller can more effectively control the rotational angle in the presence of disturbances and both the wing speed and changes in wind speed have an impact on the effectiveness of attitude *** results contribute to the development of of tailless two-winged,single-motor driven FWMAVs in terms of the design of attitude controller and testing apparatus.

关键词： Flapping-wing micro-air vehicles Sliding-mode control Pitch and roll angle-Wind gus

Aulacaspis yasumatsui infestations accelerate Cycas leaf litter decomposition and nutrient release

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Pedosphere 2024年第3期34卷 681-684页

作者： Thomas E.MARLER Bagong Kaalaman Botanikal Institute 15 Rizal StreetBarangay MalabañasAngeles City 2009(Philippines)

Dear Editor,Numerous aspects of ecosystem ecology are influenced by insects(Prasad,2022).Herbivory of plant organs by insects may influence the biogeochemistry of forests by changing the speed of litter decomposition(Schowalter,2022).Cycas micronesica *** is the only native gymnosperm in the Mariana *** once-abundant tree experienced no known lethal threats prior to the 2003 invasion of Guam by the scale Aulacaspis yasumatsui Takagi(Marler,2012).This insular case study has been the subject of abundant research(Marler et al.,2021).Changes to leaf litter chemistry improved litter quality following *** infestations(Marler and Dongol,2016),but the prediction of increased decomposition speed has not been confirmed with experimental incubations.

关键词： litter fir release

Bio-PCM Panels Composed of Renewable Materials Interact with Solar Heating Systems for Building Thermal Insulation

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Journal of Renewable Materials 2024年第4期12卷 771-798页

作者： Yosr Laatiri Habib Sammouda Fadhel Aloulou Laboratory of Energy and Materials:LabEM-LR11ES34 University of SousseHammam SousseTunisia

This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential *** contribution is the creation of insulating composite panels made of bio-based phase change materials(bio-PCM is all from coconut oil),cement and renewable materials(treated wood fiber and organic clay).The inclusion of wood fibers improved the thermal properties;a simple 2%increase of wood fiber decreased the heat conductivity by approximately 23.42%.The issues of bio-PCM leakage in the cement mortar and a roughly 56.5%reduction in thermal conductivity with bio-PCM stability in composite panels can be resolved by treating wood fibers with an adjuvant by impregnating them in bio-PCM in the presence of the treated clay *** and wood fiber were treated with adjuvants that are both biological and environmentally acceptable,as confirmed by FTIR *** heat transfer bench(DIDATEK)showed a decrease in thermal *** using differential scanning calorimetric(DSC)analysis,the investigation of thermal stability and enthalpy during two heating cycles of pure bio-PCM and composite bio-PCM was *** novel renewable material was used to create composite panels for the trial prototype,which took the shape of a component attached to the solar heating system,33.57%less heat was lost,according to the heat transfer *** outcomes demonstrated the possibility of replacing traditional electric water heating in residential buildings with solar water heating systems.

关键词： Cement wood fiber PCM thermal conductivity thermal insulation solar energy

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine Zanna Antoine Seyeux Philippe Marcus Jolanta´Swiatowska Chimie ParisTech-CNRS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen evolution

Development and testing of a high-power S-band klystron at BINP SB RAS

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Nuclear Science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov S.Samoylov D.Nikiforov V.Ivanov M.Arsentyeva D.Chekmenev O.Pavlov I.Pivovarov Budker Institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk State University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the S-band high-power klystron,accomplished at the Budker Institute of Nuclear Physics,Siberian Branch,Russian Academy of Sciences(BINP SB RAS).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 MHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

Influence of water evaporation on elastohydrodynamic lubrication with water-containing polyalkylene glycols

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Friction 2024年第10期12卷 2370-2388页

作者： Stefan HOFMANN Thomas LOHNER Karsten STAHL Technical University of Munich School of Engineering and DesignDepartment of Mechanical EngineeringGear Research Center(FZG)Boltzmannstraße 1585748 Garching near MunichGermany

The reduction of frictional power losses in power transmitting gears takes a crucial role in the design of energy-and resource-efficient ***-containing lubricants like glycerol and polyalkylene glycols have shown great potential in achieving friction within the superlubricity regime with coefficients of friction lower than 0.01 under elastohydrodynamic ***,a bio-based production of the base stocks can lead to the development of green ***,one challenge associated with the application of water-containing lubricants to gearboxes is the evaporation of water and its impact on the lubricant *** this study,the influence of water evaporation on elastohydrodynamic friction and film thickness was investigated for three water-containing polyalkylene *** nominal water contents of 20 wt%and 40 wt%and two viscosities were *** results show that the friction increases continuously with higher evaporated water content,while the overall friction level remains low in nearly water-free states.A similar trend is observed for film thickness,where the strong increase in viscosity results in a notable increase in film ***,the sensitivity of friction and film thickness to water evaporation is low for small amounts of evaporated *** allows generous thresholds for permissible variations in water content.

关键词： friction superlubricity aqueous lubrication elastohydrodynamic lubrication(EHL) evaporation polyalkylene glycol