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ELASTIC-PLASTIC ADHESION MODEL FOR SINGLE ASPERICAL ASPERITY MICROCONTACT

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Chinese Journal of Mechanical Engineering 2008年第4期21卷 101-104页

作者： peng yunfeng GUO Yinbiao Department of Mechanical Engineering Xiamen University Xiamen 361005 China

The adhesion of single asperity contacting with a rigid flat is investigated. The microcontact model of the deformable asperity is established utilizing fractal geometry, which makes the resuRed adhesion model to relate with the surface characteristics that the asperity belongs to. The Dugdale approximation is utilized to consider the adhesive interaction within and outside the contact area. Then the model for solving the elastic-plastic adhesion of single asperity is presented by combing the Maugis-Dugdale（MD） model. To illustrate the necessity of considering the plastic deformation in microcontact, simulations of the relationship between the adhesive contact load and the interference of the asperity are performed. The result shows that the presented model is more suitable for the solution of the elastic-plastic microcontact of spherical asperity due to intermolecular adhesive interactions.

关键词： Microcontact Elastic-plastic adhesion Dugdale approximation Fractal geometry

Optical local area network emulations over Ethernet passive optical networks:A survey

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Science in China(Series F) 2008年第8期51卷 1000-1009页

作者： peng yunfeng KUANG YuJun LONG KePing Research Centre for Optical Internet & Mobile Information Networks (COIMIN) Ministry Key Lab ofBroadband Optical Fiber Transmission & Communication Networks University of Electronic Science andTechnology of China Chengdu 610054 China

As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of -the-art solutions to emulating optical local area networks （OLANs） over EPON. We discuss the major problems involved, e.g., network architecture, control mechanisms, and other potential enhancements. We also outline areas for future researches.

关键词： Ethernet passive optical networks optical local area networks LAN emulation on EPON broadband access networks

Parallel lightpath provisioning under wavelength continuity constraint in multi-domain optical networks based on hierarchical path computation element

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Science China(Information Sciences) 2013年第3期56卷 160-168页

作者： SUN Jian WANG ZongWei CHEN Zhen peng yunfeng School of Communication and Information Engineering University of Electronic Science and Technology of China School of Computer and Communication Engineering University of Science and Technology Beijing

Inter-domain path provision under a wavelength continuity constraint(WCC),including path computation and resource reservation procedures,is a major challenge in multi-domain wavelength division multiplexing(WDM) optical networks,because of the requirement for confidentiality between the *** on the hierarchical path computation element(PCE) architecture,this work proposed a path establishment scheme under a WCC to provide a fast inter-domain path establishment solution and decrease the influence of the *** hierarchical PCE architecture consists of a single parent PCE serving as the arbitrator and multiple child PCEs responsible for the child *** cooperation between the parent PCE and the child PCEs,both inter-domain path computation and inter-domain wavelength reservation can be processed in parallel to accelerate and optimize WCC lightpath provisioning and thus to reduce the blocking *** effectiveness of this solution has been evaluated through *** simulation results show that the proposed solution can achieve lower computation and reservation delays and thus lead to lower blocking probabilities on the multi-domain WCC paths.

关键词： multi-domain optical networks path computation resource reservation WCC hierarchical PCE

Power-efficient RWA in dynamic WDM optical networks considering different connection holding times

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Science China(Information Sciences) 2013年第4期56卷 60-68页

作者： DU Shu ZHANG ShengFeng peng yunfeng LONG KePing Research Center for Optical Internet & Mobile Information Networks University of Electronic Science and Technology of China Institute of Advanced Network Technology University of Science & Technology Beijing

The challenges imposed by environmental issues,such as global warming and the energy crisis,are demanding more responsible energy usage,including in the optical networking *** optical transmission networks,most of the electrical power is consumed by the optical-electrical-optical conversion in optical *** optical network control plane technologies allow idle optical repeaters to be put into a low-power sleep *** by this,we propose a novel power-efficient routing and wavelength assignment(RWA) algorithm,called *** HTAPE algorithm exploits the knowledge of the connection holding times to minimize the number of optical repeaters in the active mode,and hence reduce the total electricity consumption of the optical *** test the new algorithm on the typical CERNET and USNET *** with traditional RWA algorithms without holding-time-awareness,it is observed that the HTAPE algorithm yields significant reductions in power consumption.

关键词： routing and wavelength assignment power consumption connection holding time dynamic WDM optical network

Multi-Objective Optimization for NOMA-Based Mobile Edge Computing Offloading by Maximizing System Utility

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China Communications 2023年第12期20卷 156-165页

作者： Hong Qin Haitao Du Huahua Wang Li Su yunfeng peng Chongqing University of Post and Telecom Chongqing 400065China China Mobile Research Institute Beijing 100000China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China

Mobile Edge Computing(MEC)is a technology for the fifth-generation(5G)wireless communications to enable User Equipment(UE)to offload tasks to servers deployed at the edge of ***,taking both delay and energy consumption into consideration in the 5G MEC system is usually complex and ***-orthogonal multiple access(NOMA)enable more UEs to offload their computing tasks to MEC servers using the same spectrum resources to enhance the spectrum efficiency for 5G,which makes the problem even more complex in the NOMA-MEC *** this work,a system utility maximization model is present to NOMA-MEC system,and two optimization algorithms based on Newton method and greedy algorithm respectively are proposed to jointly optimize the computing resource allocation,SIC order,transmission time slot allocation,which can easily achieve a better trade-off between the delay and energy *** simulation results prove that the proposed method is effective for NOMA-MEC systems.

关键词： computation offloading mobile edge computing non-orthogonal multiple access resource allocation

Structural characteristics of cement-stabilized soil bases with 3D finite element method

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Frontiers of Structural and Civil Engineering 2009年第4期3卷 428-434页

作者： yunfeng peng Yunlong HE College of Civil and Hydropower Engineering China Three Gorges UniversityYichang 443002China College of Water Resources and Hydroelectric Engineering Wuhan UniversityWuhan 430072China

Cement-stabilized soil bases have been widely used in expressways due to its high strength,appropriate stiffness,good water resistance,and frost *** far,the structural characteristics and mechanical behaviors of cement-stabilized soil bases were not investigated so *** this paper,the 3D elastic-plastic finite element method(FEM)was used to analyze the mechanical behaviors and structural characteristics of cementstabilized soil bases from construction to *** pavement filling and the traffic loading processes were simulated,and a contact model was used to simulate the contact behavior between each layer of the *** the construction process,the structural characteristics and mechanical behaviors of cementstabilized soil bases were studied under asphalt-concrete pavement ***,the general rules of deformations and stresses in cement-stabilized soil bases under different conditions were discussed,and some suggestions were put forward for the design and construction of cement-stabilized soil bases.

关键词： cement-stabilized soil semi-rigid base elastic-plastic finite element method structure characteristic mechanical response

Performance Analysis of Intelligent CR-NOMA Model for Industrial IoT Communications

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Computer Modeling in Engineering & Sciences 2020年第10期125卷 239-257页

作者： Yinghua Zhang Jian Liu yunfeng peng Yanfang Dong Changming Zhao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Dawning Information Industry Co. Ltd.Beijing100193China School of Computer Science Chengdu University of Information TechnologyChengdu610225China

Aiming for ultra-reliable low-latency wireless communications required in industrial internet of things(IIoT)applications,this paper studies a simple cognitive radio non-orthogonal multiple access(CR-NOMA)downlink *** system consists of two secondary users(SUs)dynamically interfered by the primary user(PU),and its performance is characterized by the outage probability of the SU *** outage probability is calculated under two conditions where,a)the transmission of PU starts after the channel state information(CSI)is acquired,so the base station(BS)is oblivious of the interference,and b)when the BS is aware of the PU interference,and the NOMA transmission is adapted to the more comprehensive knowledge of the signal to interference plus noise ratio(SINR).These results are verified by simulations,and their good agreement suggests our calculations can be used to reduce the complexity of future *** find the outage probability is reduced when the SUs move further away from the primary transmitter or when the signal from PU is less powerful,and the BS always has better performance when it is aware of the *** findings thus emphasize the importance of monitoring the channel quality and realtime feedback to optimize the performance of CR-NOMA system.

关键词： Industrial internet of things(IIoT) non-orthogonal multiple access(NOMA) quality of service(QoS) successive interference cancellation(SIC)

Damage evolution and removal behaviors of GaN crystals involved in double-grits grinding

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International Journal of Extreme Manufacturing 2024年第2期6卷 469-484页

作者： Chen Li Yuxiu Hu Zongze Wei Chongjun Wu yunfeng peng Feihu Zhang Yanquan Geng State Key Laboratory of Robotics and System(HIT) Harbin Institute of TechnologyHarbin 150001People’s Republic of China Key Laboratory of Microsystems and Microstructures Manufacturing(HIT) Harbin Institute of TechnologyHarbin 150001People’s Republic of China College of Mechanical Engineering Donghua UniversityShanghai 201620People’s Republic of China Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361005People’s Republic of China

Elucidating the complex interactions between the work material and abrasives during grinding of gallium nitride(GaN)single crystals is an active and challenging research *** this study,molecular dynamics simulations were performed on double-grits interacted grinding of GaN crystals;and the grinding force,coefficient of friction,stress distribution,plastic damage behaviors,and abrasive damage were systematically *** results demonstrated that the interacted distance in both radial and transverse directions achieved better grinding quality than that in only one *** grinding force,grinding induced stress,subsurface damage depth,and abrasive wear increase as the transverse interacted distance ***,there was no clear correlation between the interaction distance and the number of atoms in the phase transition and dislocation *** interacted distances between abrasives can decrease grinding force,coefficient of friction,grinding induced stress,subsurface damage depth,and abrasive wear during the grinding *** results of grinding tests combined with cross-sectional transmission electron micrographs validated the simulated damage results,*** atoms,high-pressure phase transition,dislocations,stacking faults,and lattice *** results of this study will deepen our understanding of damage accumulation and material removal resulting from coupling between abrasives during grinding and can be used to develop a feasible approach to the wheel design of ordered abrasives.

关键词： grinding double-grits molecular dynamics damage material removal gallium nitride

Performance Analysis of Relay Based NOMA Cooperative Transmission under Cognitive Radio Network

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Computers, Materials & Continua 2020年第4期63卷 197-212页

作者： Yinghua Zhang Jian Liu yunfeng peng Yanfang Dong Guozhong Sun Hao Huang Changming Zhao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Dawning Information Industry(Beijing)Co. Ltd.Beijing100083China Higon Austin R&D Center AustinTX 78746USA School of Computer Science Chengdu University of Information TechnologyChengdu610225China College of Computer Science Sichuan UniversityChengdu610041China

This paper proposes a hybrid spectrum accessing mechanism by using NOMA-based cooperative transmission and beam-forming *** this mechanism,the secondary user employs spectrum-sensing technology to detect the existence of the primary *** the primary user does not exist,the secondary source user directly transmits data to the destination *** the primary user exists,the secondary source user finds the optimal relay according to certain selection principle before transmitting data to the destination user through the chosen relay *** the signal receiving stage,the secondary user takes use of beam-forming technology to receive the signal from both the secondary source and the secondary relay *** the interference from the primary user is cancelled out in the ***,the outage probability for secondary user in the proposed mechanism is theoretically ***,the simulation results show that compared with the traditional mechanism,the proposed system model can not only guarantee the continuity of secondary transmission,but also significantly reduce the outage probability of secondary transmission.

关键词： Relay selection outage probability NOMA QoS signal-to-interference-plus-noise rate(SINR) beam-forming