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Blockchain-Enabled Privacy Protection and Access Control scheme Towards sensitive Digital Assets management

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China Communications 2024年第7期21卷 224-236页

作者： Duan Pengfei ma Zhaofeng Zhang Yuqing wang Jingyu Luo shoushan school of Cyberspace security Beijing University of Posts and TelecommunicationsBeijing 100876China

With the growth of requirements for data sharing,a novel business model of digital assets trading has emerged that allows data owners to sell their data for monetary *** the distributed ledger of blockchain,however,the privacy of stakeholder's identity and the confidentiality of data content are ***,we proposed a blockchainenabled privacy-preserving and access control scheme to address the above ***,the multi-channel mechanism is introduced to provide the privacy protection of distributed ledger inside the channel and achieve coarse-grained access control to digital ***,we use multi-authority attribute-based encryption(maABE)algorithm to build a fine-grained access control model for data trading in a single channel and describe its instantiation in *** analysis shows that the scheme has IND-CPA secure and can provide privacy protection and collusion *** with other schemes,our solution has better performance in privacy protection and access *** evaluation results demonstrate its effectiveness and practicability.

关键词： access control data trading maABE multi-channel privacy preserving

Hollow Metal-Organic Framework/MXene/Nanocellulose Composite Films for Giga/Terahertz Electromagnetic shielding and Photothermal Conversion

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Nano-Micro Letters 2024年第9期16卷 161-179页

作者： Tian mai Lei Chen Pei‑Lin wang Qi Liu Ming‑Guo ma Research Center of Biomass Clean Utilization MOE Engineering Research Center of Forestry Biomass Materials and BioenergyBeijing Key Laboratory of Lignocellulosic ChemistryCollege of Materials Science and TechnologyBeijing Forestry UniversityBeijing 100083People’s Republic of China state silica-Based materials Laboratory of Anhui Province Bengbu 233000People’s Republic of China

With the continuous advancement of communication technology,the escalating demand for electromagnetic shielding interference(EMI)materials with multifunctional and wideband EMI performance has become *** the electrical and magnetic components and designing the EMI material structure have attracted extensive interest,but remain a huge ***,we reported the alternating electromagnetic structure composite films composed of hollow metal-organic frameworks/layered MXene/nanocellulose(HMN)by alternating vacuum-assisted filtration *** HMN composite films exhibit excellent EMI shielding effectiveness performance in the GHz frequency(66.8 dB at Kaband)and THz frequency(114.6 dB at 0.1-4.0 THz).Besides,the HMN composite films also exhibit a high reflection loss of 39.7 dB at 0.7 THz with an effective absorption bandwidth up to 2.1 ***,HMN composite films show remarkable photothermal conversion performance,which can reach 104.6℃under 2.0 sun and 235.4℃under 0.8 W cm^(−2),*** unique micro-and macrostructural design structures will absorb more incident electromagnetic waves via interfacial polarization/multiple scattering and produce more heat energy via the local surface plasmon resonance *** features make the HMN composite film a promising candidate for advanced EMI devices for future 6G communication and the protection of electronic equipment in cold environments.

关键词： Metal-organic frameworks MXene Nanocellulose Electromagnetic shielding Photothermal conversion

spatial Equity Evaluation of Rural Eldercare service Resources Based on Accessibility: A Case study of Huanxian County of Gansu Province, China

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Chinese Geographical science 2024年第5期34卷 869-885页

作者： CHANG Xiaoyan ma Libang CUI Xijuan TAO Tianmin ZHAO shoucun College of Geography and Environmental science Northwest Normal UniversityLanzhou 730000China Key Laboratory of Resource Environment and sustainable Development of Oasis Gansu ProvinceLanzhou 730070China Northwest Institute of Urban-Rural Development and Collaborative Governance Lanzhou 730070China

safeguarding the elderly population in the countryside is an inherent requirement for alleviating social conflicts in rural areas and effectively carrying out China’s Rural *** existing spatial mismatch between rural elderly service facilities and pop-ulation distribution in China aggravates the imbalance of facility resource space,how to improve the accuracy of demand and supply results and better measuring the spatial fairness of elderly service is significant to realize the optimal allocation of rural elderly *** on the above,this study pays attention to the refined needs of the elderly population,and focuses on the spatial equity of the rural elderly facilities,to make up for the short boards of the basic public services in the countryside and realize the all-round rural *** study takes Huanxian County in the hilly loess area of Longdong,China as an example and explores the spatial equity of rural elderly services by using the Urban spatial Network Analysis(UNA)to measure the accessible quantity and supply capacity of elderly *** results found that there were 553 rural eldercare service facilities in Huanxian County,including 285 eldercare facilities and 268 medical and health facilities,and the spatial distribution is characterized by a southward shift in the east and uneven regional ***,the supply capacity of rural pension services was generally good,with the township center as the gathering point and spreading out in a faceted manner,with nearby townships forming a contiguous area;however,there were strong contrasts and obvious differences in the strength of supply ***,the spatial equity of rural eldercare service was *** 42.05%of the eld-erly population grid cells,eldercare service spatial equity was extremely *** spatial distribution also presented a northern preference over the southern,a western preference over the eastern,and a concentration along the *** stud

关键词： rural eldercare service spatial equity hilly loess region of Longdong Huanxian County China

Microstructures,Deformation Mechanisms and seismic Properties of synkinematic Migmatite from southeastern Tibet:Insights from the Migmatitic Core of the Ailao shan-Red River shear Zone,Western Yunnan,China

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Journal of Earth science 2024年第4期35卷 1149-1169页

作者： Weiwei ma Bo Zhang Fulong Cai Baoyou Huang Lei Zhang Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing100871China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100085China

seismic anisotropy originating within the continental crust is commonly used to determine the deformation and kinematic flow within active orogens and is attributed to regionally oriented mica or hornblende ***,naturally deformed rocks usually contain compositional layers(e.g.,parallel compositional banding).It is necessary to understand how both varying mineral contents and differing intensities of compositional layering influence the seismic properties of the deep *** this study,we analyzed the seismic response of migmatitic amphibolite with compositional banding *** present the microstructures,fabrics,calculated seismic velocities,and seismic anisotropies of mylonitic amphibolite from a horizontal shear layer preserved within the Ailao shan-Red River shear zone,southwestern Yunnan,*** investigated sample is characterized by pronounced centimeter-scale compositional *** microstructures and fabrics suggest that migmatitic amphibolite rocks within deep crust may delineate regions of deformation-assisted,channelized,reactive,porous melt *** origin of compositional banding in the studied migmatitic amphibolite is attributed primarily to partial melting together with some horizontal shearing *** microfabrics and structures investigated in this study are considered to be typical for the base of active horizontal shear layers in the deep crust of southeastern *** responses are modeled by using crystal preferred orientations for minerals of the migmatitic amphibolite by applying the Voigt-Reuss-Hill homogenization *** P-wave and s-wave velocities are largely consistent in the various layers of the ***,seismic anisotropies of P-wave(AV_(p))and s-wave(AVs)are higher in the melanosomes(AV_(p)=5.6%,AV_(s)=6.83%)than those in the leucosomes and the whole rock(AV_(p)=4.2%–4.6%,AV_(s)=3.1%–3.2%).In addition,there is pronounced,s-wave splitting oblique to the foliation plane in the migm

关键词： deformation-assisted melt flow seismic anisotropy microstructure compositional banding migmatite deep crust southeastern Tibet

Analysis of Tidal Current Energy Potential in the major Channels of the Bohai strait Based on Delft3D

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Journal of Ocean University of China 2024年第4期23卷 859-870页

作者： ma Pengcheng sHI Hongyuan XUE Huaiyuan LI Pingping sUN Yongkang school of Hydraulic Engineering Ludong University of ChinaYantai 264025China Institute of Coastal Research Ludong University of ChinaYantai 264025China Yantai Kekan marine Technology Co. Ltd.Yantai 264025China

The utilization and development of tidal current energy can help alleviate the current energy shortage,improve the global ecological environment,and maintain sustainable *** this study,numerical simulation is carried out on a rectangular grid using *** tidal current energy potential of the major channels in the Bohai strait is further simulated and estimated by comparing the simulated and measured *** show that the flow module in Delft3D has good modeling ability for the assessment of tidal current energy *** average flow velocity,maximum flow velocity,and energy flow density are *** Laotieshan Channel,located in the northern part of the Bohai strait,shows a large tidal current energy *** maximum flow velocity of this channel can reach 2 m s-1,and the maximum energy flow density can exceed 500 W *** tidal current energy in the Laotieshan Channel is more than 10 times that in other ***,this study advocates for the continued exploration and exploitation of the tidal current energy resources in the Laotieshan Channel.

关键词： Delft3D Bohai strait tidal current energy numerical simulation power density

Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements

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Defence Technology（防务技术） 2024年第2期32卷 473-484页

作者： Yiming Zhang Ningfei wang Weihua ma Ran wang Long Bai Yi Wu school of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing system Design Institute of Electro-mechanic Engineering Beijing 100854China Xi'an Changfeng Research Institute of Mechanism and Electricity Xi'an 710065China

In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were *** projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 *** onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and *** compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching *** the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant *** calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were *** dynamic mechanical response process of the dummy propellant grain was analysed in *** results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.

关键词： Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response

Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China

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Acta Geologica sinica(English Edition) 2024年第2期98卷 468-476页

作者： ZHANG shouchuan LIU Kai ma Yan waNG Luyao sUN Junliang Chinese Academy of Geological sciences Beijing 100037China school of water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic *** study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health *** results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDs with a large variation across the range 471-2337 mg/*** NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited ***,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline ***,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic *** alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population *** results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s *** findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District.

关键词： fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District

Investigating spatio-temporal characteristics and influencing factors for green energy consumption in China

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Geoscience Frontiers 2024年第3期15卷 221-236页

作者： Xiaowei ma shimei Weng Jun Zhao Huiling Liu Hongyun Huang school of Finance Anhui University of Finance and EconomicsBengbu 233030PR China Hefei Advanced Research Institute Anhui University of Finance and EconomicsHefei 230041PR China school of mathematics and statistics Fujian Normal UniversityFuzhou 350117PR China school of Economics and management Beijing University of Chemical TechnologyBeijing 100029PR China school of Economics Hefei University of TechnologyHefei 230601PR China Qingdao Institute of Humanities and social sciences Shandong UniversityQingdao 266237PR China Center for Yellow River Ecosystem Products Shandong UniversityQingdao 266237PR China

The green transformation of energy consumption is beneficial for promoting green development in *** study constructed a green energy consumption evaluation index system and measured the green energy consumption levels in 30 provinces of China from 2000 to 2019 using the fuzzy comprehensive evaluation *** study further employed the spatial Durbin model to examine influencing factors and spillover effects of green energy *** results showed that,temporally,China’s green energy consumption levels had a fluctuating upward ***,spatially,the overall levels of green energy consumption in China showed apparent characteristics of“high in the west and low in the east”.In terms of influencing factors,environmental regulations played an important role in promoting green energy consumption in the region,while economic development,opening up,and industrial structure had considerably inhibiting ***,economic development,opening up,and industrial structure of neighboring regions showed marked positive spillover effects,while urbanization level and technological innovation showed substantial negative spillover *** regional heterogeneity test results showed that environmental regulation and industrial structure rationalization were the important factors for promoting green energy consumption in the eastern region,environmental regulation played an important driving role in the central region,and opening to the outside world and technological innovation helped improve the level of green energy consumption in the western region.

关键词： Energy green consumption spatial and temporal characteristics Influencing factors spatial Durbin model Regional heterogeneity

Experimental study of the damage characteristics of rocks containing non-penetrating cracks under cyclic loading

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International Journal of Mining science and Technology 2024年第2期34卷 197-210页

作者： Jun Xu Xiaochun Xiao Lu ma sen Luo Jiaxu Jin Baijian Wu school of Mechanics and Engineering Liaoning Technical UniversityFuxin 123000China school of Civil Engineering Liaoning Technical UniversityFuxin 123000China Department of Engineering Mechanics Southeast UniversityNanjing 211189China

The damage evolution process of non-penetrating cracks often causes some unexpected engineering *** specimens containing non-penetrating crack(s)are used to study the damage evolution and characteristics under cyclic *** results show that under cyclic loading,the relationship between the number of non-penetrating crack(s)and the characteristic parameters(cyclic number,peak stress,peak strain,failure stress,and failure strain)of the pre-cracked specimens can be represented by a decreasing linear *** damage evolution equation is fitted by calibrating the accumulative plastic strain for each cycle,and the damage constitutive equation is proposed by the concept of effective ***,non-penetrating cracks are more likely to cause uneven stress distribution,damage accumulation,and local failure of *** local failure can change the stress distribution and relieve the inhibition of non-penetrating crack extension and eventually cause a dramatic destruction of the ***,the evolution process caused by non-penetrating cracks can be regarded as one of the important reasons for inducing *** results are expected to improve the understanding of the process of spalling formation and rockburst and can be used to analyze the stability of rocks or rock structures.

关键词： Damage characteristics Constitutive model Fissured rocks Non-penetrating crack Cyclic loading