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Path Computing Scheme with Low-Latency and Low-Power in Hybrid Cloud-Fog Network for IIoT

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China Communications 2023年第8期20卷 1-16页

作者： Jijun Ren Peng Zhu Zhiyuan Ren School of Communications and Information Engineering Xi’an University of Posts&TelecommunicationsShaanxi 710061China State Key Laboratory of Integrated Services Networks Xidian UniversityShaanxi 710071China

With the rapid development of the Industrial Internet of Things(IIoT),the traditional centralized cloud processing model has encountered the challenges of high communication latency and high energy consumption in handling industrial big data tasks.This paper aims to propose a low-latency and lowenergy path computing scheme for the above problems.This scheme is based on the cloud-fog network architecture.The computing resources of fog network devices in the fog computing layer are used to complete task processing step by step during the data interaction from industrial field devices to the cloud center.A collaborative scheduling strategy based on the particle diversity discrete binary particle swarm optimization(PDBPSO)algorithm is proposed to deploy manufacturing tasks to the fog computing layer reasonably.The task in the form of a directed acyclic graph(DAG)is mapped to a factory fog network in the form of an undirected graph(UG)to find the appropriate computing path for the task,significantly reducing the task processing latency under energy consumption constraints.Simulation experiments show that this scheme’s latency performance outperforms the strategy that tasks are wholly offloaded to the cloud and the strategy that tasks are entirely offloaded to the edge equipment.

关键词： collaborative offloading strategy cloudfog network architecture industrial internet of things path computing PDBPSO

A stabilizer-free C^(0) weak Galerkin method for the biharmonic equations

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Science China Mathematics 2023年第3期66卷 627-646页

作者： Peng Zhu Shenglan Xie Xiaoshen Wang College of Data Science Jiaxing UniversityJiaxing 314001China College of Information Engineering Jiaxing Nanhu UniversityJiaxing 314001China Department of Mathematics University of Arkansas at Little RockLittle RockAR 72204USA

In this article, we present and analyze a stabilizer-free C^(0)weak Galerkin(SF-C^(0)WG) method for solving the biharmonic problem. The SF-C^(0)WG method is formulated in terms of cell unknowns which are C^(0)continuous piecewise polynomials of degree k + 2 with k≥0 and in terms of face unknowns which are discontinuous piecewise polynomials of degree k + 1. The formulation of this SF-C^(0)WG method is without the stabilized or penalty term and is as simple as the C1conforming finite element scheme of the biharmonic problem. Optimal order error estimates in a discrete H^(2)-like norm and the H^(1)norm for k≥0 are established for the corresponding WG finite element solutions. Error estimates in the L^(2)norm are also derived with an optimal order of convergence for k > 0 and sub-optimal order of convergence for k = 0. Numerical experiments are shown to confirm the theoretical results.

关键词： weak Galerkin finite element method weak Laplacian biharmonic equations

Multiple Random Forests Based Intelligent Location of Single-phase Grounding Fault in Power Lines of DFIG-based Wind Farm

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1152-1163页

作者： Yongli zhu Hua peng School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding 071003China

To address the problems of wind power abandonment and the stoppage of electricity transmission caused by a short circuit in a power line of a doubly-fed induction generator(DFIG) based wind farm, this paper proposes an intelligent location method for a single-phase grounding fault based on a multiple random forests(multi-RF) algorithm. First, the simulation model is built, and the fundamental amplitudes of the zerosequence currents are extracted by a fast Fourier transform(FFT) to construct the feature set. Then, the random forest classification algorithm is applied to establish the fault section locator. The model is resampled on the basis of the bootstrap method to generate multiple sample subsets, which are used to establish multiple classification and regression tree(CART) classifiers. The CART classifiers use the mean decrease in the node impurity as the feature importance,which is used to mine the relationship between features and fault sections. Subsequently, a fault section is identified by voting on the test results for each classifier. Finally, a multi-RF regression fault locator is built to output the predicted fault distance. Experimental results with PSCAD/EMTDC software show that the proposed method can overcome the shortcomings of a single RF and has the advantage of locating a short hybrid overhead/cable line with multiple branches. Compared with support vector machines(SVMs)and previously reported methods, the proposed method can meet the location accuracy and efficiency requirements of a DFIG-based wind farm better.

关键词： Doubly-fed induction generator(DFIG)based wind farm power line multiple random forests(multi-RF) single-phase grounding fault fault location

Fault-Tolerant Operation of Five-Phase Permanent Magnet Synchronous Motor with Independent Phase Driving Control

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 105-110页

作者： Yongqing Wei Mingzhong Qiao Peng Zhu College of Electrical Engineering Naval University of EngineeringWuhan430033China

The multi-phase motor drive system with multiple H-bridge power supply has high fault tolerance,which is widely used in aerospace,electric vehicle,ship integrated power system and other fields.In this paper,a fault-tolerant control strategy based on decoupling control and stator current compensation is proposed for the propulsion system of five-phase PMSM with independent neutrals.Firstly,the mathematical model of PMSM is established by using vector space decoupling method;Secondly,a stator current compensation method is adopted to carry out fault-tolerant control after the motor has single-phase and two-phase open-circuit faults and the fault-tolerant control system based on decoupling control is established;Finally,the decoupling control model and the fault-tolerant control of stator current compensation are verified by the simulation and experiment.The simulation and experiment results show that the method can reduce the torque ripple caused by the stator winding open-circuit fault,and the operation performance of the motor under fault condition is significantly improved.

关键词： Five-Phase permanent magnet synchronous motor H-bridge inverter Fault-tolerant control Vector space decoupling

Fatigue shear performance of concrete beams reinforced with hybrid(glass-fiber-reinforced polymer+steel)rebars and stirrups

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 576-594页

作者： Peng Zhu Jiajing XU Wenjun QU Department of Structural Engineering Tongji UniversityShanghai200092China School of Transportation and Civil Engineering Nantong UniversityNantong226019China

Reinforced concrete beams consisting of both steel and glass-fiber-reinforced polymer rebars exhibit excellent strength,serviceability,and durability.However,the fatigue shear performance of such beams is unclear.Therefore,beams with hybrid longitudinal bars and hybrid stirrups were designed,and fatigue shear tests were performed.For specimens that failed by fatigue shear,all the glass-fiber-reinforced polymer stirrups and some steel stirrups fractured at the critical diagonal crack.For the specimen that failed by the static test after 8 million fatigue cycles,the static capacity after fatigue did not significantly decrease compared with the calculated value.The initial fatigue level has a greater influence on the crack development and fatigue life than the fatigue level in the later phase.The fatigue strength of the glass-fiber-reinforced polymer stirrups in the specimens was considerably lower than that of the axial tension tests on the glass-fiber-reinforced polymer bar in air and beam-hinge tests on the glass-fiber-reinforced polymer bar,and the failure modes were different.Glass-fiber-reinforced polymer stirrups were subjected to fatigue tension and shear,and failed owing to shear.

关键词： fatigue shear hybrid stirrups hybrid reinforcement fiber-reinforced polymer

Bimetal MOF-derived NiFe-P nanocomposites coupled with Cu_(3)P nanoparticles to construct tandem electron transfer channels for photocatalytic hydrogen evolution

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Journal of Environmental Sciences 2024年第3期137卷 333-346页

作者： Haiyan Zhang Shitao Yang Peng Zhu Senpei Tang Ming Li College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Account Hunan University of Technology and BusinessChangsha 410205China

Finely modulated light-induced charge separation and transfer is a central challenge to achieve efficient photocatalysis.Although progress has been made in this field,most of the previous research works focused on the separation or migration of photogenerated carriers but did not build a bridge between the two.How to realize the strong driving and precise migration of carriers has become the focus of our work.We report an ingeniously designed ternary heterojunction.Taking NiFe-MOF as the“parent material”,the FeP_(4)/Ni_(x)P_(y)heterojunction is derived in situ while maintaining the frame structure through gas-solid reaction,and finally the Z-type electron transfer is realized.With Cu_(3)P anchoring spindle matrix,an electron transport tunnel is opened up in Cu_(3)P/FeP_(4)/Ni_(x)P_(y)ternary heterojunction under the action of p-n heterojunction built-in electric field driving and accurate energy band matching.The strong driving force of the built-in electric field provides an inexhaustible power for the transmission of electrons,and the fine series of electron transmission channels realizes the precise transmission of electrons.The above fine design makes the perfect fit between the built-in electric field and the electron transfer channel,which not only effectively improves the embarrassing situation of insufficient electron driving force of hydrogen evolution reaction in the previous research,but also makes up for the weakening of semi-conductor reduction ability caused by the construction of traditional p-n heterostructures.This research work provides a new idea for the construction of multiple heterostructures and the design of fine interface engineering in the future.

关键词： Cu_(3)P/FeP_(4)/Ni_(x)P Built-in electric field Electron transfer channels Photocatalysis

Meniscus-Assisted Solution Printing Enables Cocrystallization in Poly(3-alkylthiophene)-based Blends for Field-Effect Transistors

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Chinese Journal of Polymer Science 2023年第8期41卷 1269-1276,I0009页

作者： Shu-Yin zhu Juan peng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

The formation of cocrystallization in two various conjugated components may endow the newly formed conjugated cocrystals with multiple functionalities and improved charge transport properties.However,compared to conjugated small molecules,this strategy is rather limitedly realized in conjugated polymers.Herein,a simple meniscus-assisted solution printing(MASP)strategy is utilized to achieve the cocrystallization in the blends of two conjugated polymers,i.e.,poly(3-hexylthiophene)(P3HT)and poly(3-octylthiophene)(P3OT),and the cocrystalline structures are correlated closely to their charge mobilities.The P3HT/P3OT blends phase separate and crystallize individually in their drop-cast thin films.When subjecting the P3HT/P3OT blended solution to MASP,the confined solvent evaporation between two nearly parallel plates triggers them to cocrystallize progressively when accelerating the moving lower plate.The cocrystallization kinetics and the changes in P3HT/P3OT molecular structures are elucidated.Finally,these different crystalline structures of P3HT/P3OT blends are applied in organic fieldeffect transistors,imparting the cocrystallization-enhanced charge transport than respective P3HT and P3OT crystal domains.Such MASP method can be extended to craft cocrystals of other conjugated polymer blends for their diverse optoelectronic applications.

关键词： Conjugated polymer blends Polythiophene Cocrystallization Charge mobility Meniscus-assisted solution printing

Machine learning identified genetic features associated with HIV sequences in the monocytes

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Chinese Medical Journal 2023年第24期136卷 3002-3004页

作者： Xiaorong peng Biao zhu State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310003China

To the Editor:Human immunodeficiency virus(HIV)DNA has been detected in circulating monocytes isolated from HIV-infected individuals with or without antiretroviral therapy(ART).[1]Infrequent and low levels of HIV DNA were detected in circulating monocytes.[2]Monocytes harbor replication-competent,non-latent HIV-1 in patients on ART.Earlier studies on circulating monocytes have revealed distinct viral populations and genetic characteristics compared to T cells.[3,4]However,there is currently no easy way to clearly distinguish virus in monocyte from virus in T-cell.

关键词： monocytes latent harbor

Long-term effects of electrochemical realkalization on carbonated concrete

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 127-137页

作者： Peng Zhu Ji ZHANG Wenjun QU College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures Shanghai 200092China

The long-term effects of electrochemical realkalization on carbonated reinforced concrete with a W/C ratio of 0.65 were studied.Fourteen out of 16 carbonated specimens had been subjected to realkalization seven years ago,and the alkalinity of the concrete,the electrochemical characters(corrosion current density and potential)of the specimens and the corrosion conditions of the steel bars were examined.Results of different specimens and also at different time(4,10,13 months and 7 years after realkalization)were compared.According to the phenolphthalein and pH meter test,the alkalinity of the concrete had disappeared after seven years.Based on the potentiodynamic polarization test,various corrosion conditions had developed on the steel bars,which was verified by visual observation.All bars were in the depassivated state,and their corrosion current densities increased significantly after seven years.Cracks developed in some of the specimens,and the diverse compactness of concrete and excessive current of realkalization were considered to be possible causes.The effects of the realkalization treatment vanished after seven years.

关键词： realkalization concrete carbonation polarization curve corrosion