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Big Data Access Control Mechanism Based on Two-Layer Permission Decision Structure

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Computers, Materials & Continua 2024年第4期79卷 1705-1726页

作者： Aodi Liu Na wang Xuehui Du Dibin Shan Xiangyu Wu wenjuan wang He’nan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policymanagement efficiency and difficulty in accurately describing the access control policy. To overcome theseproblems, this paper proposes a big data access control mechanism based on a two-layer permission decisionstructure. This mechanism extends the attribute-based access control (ABAC) model. Business attributes areintroduced in the ABAC model as business constraints between entities. The proposed mechanism implementsa two-layer permission decision structure composed of the inherent attributes of access control entities and thebusiness attributes, which constitute the general permission decision algorithm based on logical calculation andthe business permission decision algorithm based on a bi-directional long short-term memory (BiLSTM) neuralnetwork, respectively. The general permission decision algorithm is used to implement accurate policy decisions,while the business permission decision algorithm implements fuzzy decisions based on the business constraints.The BiLSTM neural network is used to calculate the similarity of the business attributes to realize intelligent,adaptive, and efficient access control permission decisions. Through the two-layer permission decision structure,the complex and diverse big data access control management requirements can be satisfied by considering thesecurity and availability of resources. Experimental results show that the proposed mechanism is effective andreliable. In summary, it can efficiently support the secure sharing of big data resources.

关键词： Big data access control data security BiLSTM

MOF-mediated synthesis of novel PtFeCoNiMn high-entropy nanoalloy as bifunctional oxygen electrocatalysts for zinc-air battery

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Nano Research 2024年第6期17卷 5288-5297页

作者： Mingkuan Xie Xin Xiao Duojie Wu Cheng Zhen Chunsheng Wu wenjuan wang Hao Nian Fayan Li Meng Danny Gu Qiang Xu Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) Shenzhen 518055China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL) Shenzhen 518055China Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of Guangdong Southern University of Science and TechnologyShenzhen 518055China Eastern Institute for Advanced Study Eastern Institute of TechnologyNingbo 315200China

High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional properties.The electronic structure regulation of HEAs plays a pivotal role in enhancing their elctrocatalytic ability.Herein,PtFeCoNiMn nanoparticles(NPs)with subtle lattice distortions are constructed on metal-organic framework-derived nitrogen-doped carbon by an ultra-rapid Joule heating process.Thanks to the modulated electronic structure and the inherent cocktail effect of HEAs,the as-synthesized PtFeCoNiMn/NC exhibits superior bifunctional electrocatalytic performance with a positive half-wave potential of 0.863 V vs.reversible hydrogen electrode(RHE)for oxygen reduction reaction and a low overpotential of 357 mV at 10 mA·cm^(-2)for oxygen evolution reaction.The assembled quasi-solid-state zinc-air battery using PtFeCoNiMn/NC as air electrode shows a high peak power density of 192.16 mW·cm^(-2),low charge−discharge voltage gap,and excellent durability over 500 cycles at 5 mA·cm^(-2).This work demonstrates an effective route for rational design of bifunctional nanostructured HEA electrocatalysts with favorable electronic structures,and opens up a fascinating directions for energy storage and conversion,and beyond.

关键词： oxygen reduction reaction oxygen evolution reaction high-entropy nano-alloy zinc-air battery

Benefit of aerosol reduction to winter wheat during China's clean air action:A case study of Henan Province

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Journal of Environmental Sciences 2024年第7期141卷 90-101页

作者： Yang Bai Pengfei Zhao Xueyang Chen Lijun wang wenjuan Chang Jianzhong Guo Jiayao wang College of Geography and Environmental Science Henan UniversityKaifeng 475004China Henan Industrial Technology Academy of Spatio-Temporal Big Data Henan UniversityZhengzhou 475000China Henan Technology Innovation Center of Spatio-Temporal Big Data Henan UniversityZhengzhou 450046China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475000China

A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains unclear.We use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to 2018.After calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GLUE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more accurately.We found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to maturity.Due to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing seasons.As a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,respectively.Our findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.

关键词： Haze pollution Clean air action Aerosol-induced radiative perturbation Wheat production DSSAT model

Connections Between Induction Generator Effect and Open-loop Modal Proximity to Cause Sub-synchronous Oscillations in Series-compensated Power System

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 963-973页

作者： wenjuan Du Yang wang H.F.wang Tao Zhao Tim Littler College of Electrical Engineering Sichuan UniversityChengduChina School of Electrical Engineering the Queen’s University of BelfastBelfastUK IEEE

The induction generator effect(IGE)and the openloop modal proximity(OLMP)are two different reasons why subsynchronous oscillations(SSOs)in a series-compensated power system(SCPS)may occur.The IGE attributes the growing SSOs to negative resistance,while the OLMP explains the SSO mechanism from the standpoint of modal conditions.In this paper,we investigate the connections between the IGE and the OLMP through equivalent RLC circuit and open-loop modal analysis.Our investigation is conducted for two types of seriescompensated power systems where either a synchronous generator or a DFIG is connected at the sending end.The investigation reveals the conditions,in which the IGE and the OLMP may jointly cause the growing SSOs,i.e.,both the IGE and the OLMP can explain why the growing SSOs occur.Furthermore,the investigation indicates that the IGE and the OLMP may be totally irrelevant and lead to growing SSOs separately.This implies that it is possible that in a SCPS,the growing SSOs are only due to the IGE,and the OLMP is non-existent,and vice versa.Hence,when the growing SSOs occurs in a SCPS,examination based on both the IGE and the OLMP should be carefully conducted in order to find if the oscillatory instability is due to the IGE,or the OLMP,or both of them.

关键词： Induction generator effect open-loop modal proximity series compensation sub-synchronous oscillations

Hydrodynamic analysis of carbon nanotube clusters in distributor-less conical fluidized beds with step-by-step scaling

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Chinese Journal of Chemical Engineering 2024年第3期67卷 117-125页

作者： Tianle Zhang wenjuan Bai Qianpeng Dong Dianming Chu Lianlian wang Yan He Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266061China Shandong Dazhan Nano Materials Co. Ltd.Binzhou 256220China

As a high-performance material with great application potential,the application of carbon nanotubes has been limited by their production volume.A distributor-less conical fluidized bed is the main equipment used in the industrial production of carbon nanotubes.To improve the production volume and product quality of carbon nanotubes,the study of fluidized-bed-diameter scaling is important.Three different diameters of distributor-less conical fluidized beds were established,and then the particle behavior and bubble characteristics of carbon nanotube clusters at these bed diameters were investigated.Time-series and wavelet analysis methods were used to analyze the pressure-fluctuation signals inside the fluidized beds.Results showed that the distributor-less design caused the airflow to break through the middle of the bed,which did not change with the change in bed diameter.The powder-bridging phenomenon of carbon nanotube clusters in a 100-mm-diameter fluidized bed was related to the special microstructure of carbon nanotube clusters.The frequency of pressure fluctuations in the bed decreased nonlinearly with increasing bed diameter.This study can guide the design and scale-up of distributor-less conical fluidized beds,especially for the scale-up of carbon nanotube production equipment,which can contribute to the improvement of carbon nanotubes’capacity and quality in industrial production.

关键词： Carbon nanotubes Fluidized bed Multiphase flow Scale-up Multiscale

Bioinspired Tactile Sensation Based on Synergistic Microcrack-Bristle Structure Design toward High Mechanical Sensitivity and Direction-Resolving Capability

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Research 2024年第1期2023卷 611-624页

作者： Yiqun Zhang Qi Liu wenjuan Ren Yangyang Song Hua Luo Yangyang Han Liang He Xiaodong Wu Zhuqing wang School of Mechanical Engineering Sichuan UniversityChengdu 610065China Med+X Center for Manufacturing West China HospitalSichuan UniversityChengdu 610041China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

Natural tactile sensation is complex,which involves not only contact force intensity detection but also the perception of the force direction,the surface texture,and other mechanical parameters.Nevertheless,the vast majority of the developed tactile sensors can only detect the normal force,but usually cannot resolve shear force or even distinguish the directions of the force.Here,we present a new paradigm of bioinspired tactile sensors for resolving both the intensity and the directions of mechanical stimulations via synergistic microcrack-bristle structure design and cross-shaped configuration engineering.The microcrack sensing structure gives high mechanical sensitivity to the tactile sensors,and the synergistic bristle structure further amplifies the sensitivity of the sensors.The cross-shaped configuration engineering of the synergistic microcrack-bristle structure further endows the tactile sensors with good capability to detect and distinguish the directions of the applied mechanical forces.The as-fabricated tactile sensors exhibit a high sensitivity(25.76 N^(−1)),low detection limit(5.4 mN),desirable stability(over 2,500 cycles),and good capability to resolve both mechanical intensity and directional features.As promising application scenarios,surface texture recognition and biomimetic path explorations are successfully demonstrated with these tactile sensors.This newly proposed tactile sensation strategy and technology have great potential applications in ingenious tactile sensation and construction of various robotic and bionic prostheses with high operational dexterity.

关键词： crack sensation directions

Preparation of high-purity fluorite and nanoscale calcium carbonate from low-grade fluorite

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1198-1207页

作者： Qianqian Lu Haisheng Han wenjuan Sun Xingfei Zhang Weiwei wang Bilan Zhang Wensheng Chen Qin Zou School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Hunan Nonferrous Chenzhou Fluoride Chemical Co. Ltd.Chenzhou 423000China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China Hunan Shizhuyuan Nonferrous Metal Co. Ltd.Chenzhou 423000China

Flotation separation of calcite from fluorite is a challenge on low-grade fluorite flotation that limits the recovery and purity of fluorite concentrate.A new acid leaching–flotation process for fluorite is proposed in this work.This innovative process raised the fluor-ite’s grade to 97.26wt%while producing nanoscale calcium carbonate from its leachate,which contained plenty of calcium ions.On the production of nanoscale calcium carbonate,the impacts of concentration,temperature,and titration rate were examined.By modifying the process conditions and utilizing crystal conditioning agents,calcite-type and amorphous calcium carbonates with corresponding particle sizes of 1.823 and 1.511μm were produced.The influence of the impurity ions Mn^(2+),Mg^(2+),and Fe^(3+)was demonstrated to reduce the particle size of nanoscale calcium carbonate and make crystal shape easier to manage in the fluorite leach solution system compared with the calcium chloride solution.The combination of the acid leaching–flotation process and the nanoscale calcium carbonate preparation method improved the grade of fluorite while recovering calcite resources,thus presenting a novel idea for the effective and clean usage of low-quality fluorite resources with embedded microfine particles.

关键词： fluorite calcite nanoscale calcium carbonate waste recovery

Stem Cell-Based Hair Cell Regeneration and Therapy in the Inner Ear

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Neuroscience Bulletin 2024年第1期40卷 113-126页

作者： Jieyu Qi wenjuan Huang Yicheng Lu Xuehan Yang Yinyi Zhou Tian Chen Xiaohan wang Yafeng Yu Jia-Qiang Sun Renjie Chai State Key Laboratory of Digital Medical Engineering Department of Otolaryngology Head and Neck SurgeryZhongda HospitalSchool of Life Sciences and TechnologyAdvanced Institute for Life and HealthJiangsu Province High-Tech Key Laboratory for Bio-Medical ResearchSoutheast UniversityNanjing 210096China Hospital of Southeast University Nanjing 210096China First Affiliated Hospital of Soochow University Suzhou 215006China Department of Otolaryngology-Head and Neck Surgery The First Affliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Otolaryngology Head and Neck Surgery Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China Co-Innovation Center of Neuroregeneration Nantong UniversityNantong 226001China Institute for Stem Cell and Regeneration Chinese Academy of ScienceBeijing 100101China

Hearing loss has become increasingly prevalent and causes considerable disability,thus gravely burdening the global economy.Irreversible loss of hair cells is a main cause of sensorineural hearing loss,and currently,the only relatively effective clinical treatments are limited to digital hearing equipment like cochlear implants and hearing aids,but these are of limited benefit in patients.It is therefore urgent to understand the mechanisms of damage repair in order to develop new neuroprotective strategies.At present,how to promote the regeneration of functional hair cells is a key scientific question in the field of hearing research.Multi-ple signaling pathways and transcriptional factors trigger the activation of hair cell progenitors and ensure the maturation of newborn hair cells,and in this article,we first review the principal mechanisms underlying hair cell reproduction.We then further discuss therapeutic strategies involving the co-regulation of multiple signaling pathways in order to induce effective functional hair cell regeneration after degeneration,and we summarize current achievements in hair cell regeneration.Lastly,we discuss potential future approaches,such as small molecule drugs and gene therapy,which might be applied for regenerating functional hair cells in the clinic.

关键词： Hearing loss Cochlea-Stem cell Hair cell regeneration

Simulation and test on the operation process of an intermittent filmpicking component on full-film mulched double ditches

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 99-108页

作者： Fei Dai Feng wang wenjuan Guo Ruijie Shi Shanglong Xin Xiaolong Liu Wuyun Zhao College of Mechanical and Electrical Engineering Gansu Agricultural UniversityLanzhou 730070China School of Cyber Security Gansu University of Political Science and LawLanzhou 730070China

In view of the problems in operation process of fixed rake-type residual recycling component,such as poor individual profiling effect in film picking,easy clogging of the compound of films,soil and corn stubbles,high power consumption in film picking,and strong disturbance to seedbed soil,in this study,an operation model of intermittent filmpicking on full-film mulched double ditches was proposed and an intermittent film picking component was designed.The DEMMBD coupled algorithm was adopted for numerical simulation on the operation process of the intermittent film-picking component on full-film mulched double ditches,and a comparative analysis was carried out on the seedbed disturbance effect and resistance variation characteristics in film-picking by fixed and intermittent film-picking components.By taking the forward speed in film-picking,cam arrangement angle of the film-picking component and rotating speed of the cam shaft as independent variables,film-picking rate as the response value,a mathematical model between test factors and the film-picking rate was established,to explore the influence order of the factors on film-picking rate,and the optimal working parameters of the intermittent film-picking component were obtained as follows:the forward speed in film-picking was 2 km/h,cam arrangement angle was 180°,rotating speed of the cam shaft was 120 r/min.Under the optimal parameter combination,the average film-picking rate of the simulation test was 96.1%.Field test showed that,the average film-picking rate of the intermittent film-picking component was 95.6%,and 0.5%higher than that of the simulation test.The working condition of the sample machine was basically consistent with the simulation process,and can accurately represent the operation mechanism of intermittent film-picking on full-film mulched double ditches,showing that the established discrete element simulation model and its parameters were accurate and reasonable.

关键词： full-film mulched double ditches residual film recovery intermittent film-picking component DEM-MBD parameter optimization