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Energy Engineering 2024年第4期121卷 1007-1026页

作者： Zhuo Chen Ningning Wang wenbo jin Dui Li The Second Oil Production Plant Sinopec Northwest Oilfield CompanyUrumqi830011China Yingmaili Oil and Gas Production Management Area PetroChina Tarim Oilfield CompanyKorla841001China College of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065China

A hard problem that hinders the movement of waxy crude oil is wax deposition in oil pipelines.To ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil pipelines.Aiming at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is proposed.The validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil pipelines.The two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,respectively.Additionally,it shows a higher prediction accuracy compared to the ENN prediction model.In fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.

关键词： Waxy crude oil wax deposition rate chaotic map improved reptile search algorithm Elman neural network prediction accuracy

Modeling and analysis of oil frictional loss in wet-type permanent magnet synchronous motor for aerospace electro-hydrostatic actuator

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Chinese Journal of Aeronautics 2023年第11期36卷 328-341页

作者： jinquan XU wenbo jin Hong GUO Tian YU Wenhu FAN Zongxia JIAO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315800China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

To improve the power density and simplify the seal structure,the Wet-Type Permanent Magnet Synchronous Motor(WTPMSM)technique has been applied to aerospace Electro-Hydrostatic Actuators(EHA).In a WTPMSM,the stator and the rotor are both immersed in the aviation hydraulic oil.Although the heat dissipation performance of the WTPMSM can be enhanced,the aviation hydraulic oil will cost an extra oil frictional loss in the narrow airgap of the WTPMSM.This paper proposes an accurate oil frictional loss model for the WTPMSM,in which the wide speed range(0–20 kr/min)and the narrowness of the airgap(0.5–1.5 mm)are its features.Firstly,the mechanism of the oil frictional loss in the airgap of the WTPMSM is revealed.Then an accurate oil frictional loss model is proposed considering the nonlinear influence caused by the Taylor vortex.Furthermore,the influence of motor dimensions on oil frictional loss is analyzed.Finally,the proposed oil frictional loss model is verified by experiments,which provides a guideline for engineers to follow in the WTPMSM design.

关键词： Electro-hydrostatic actuator Motor dimensions Oil frictional loss Taylor vortex Wet-type permanent magnet synchronous motor

Effect of Ni content on the wear behavior of Al-Si-Cu-Mg-Ni/SiC particles composites

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 374-383页

作者： Yanyu Liu Lina Jia wenbo Wang Zuheng jin Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315100China Qingdao Research Institute of Beihang University Qingdao 266000China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

In recent years,the addition of Ni has been widely acknowledged to be capable of enhancing the mechanical properties of Al-Si alloys.However,the effect of Ni on the wear behaviors of Al-Si alloys and Al matrix composites,particularly at elevated temperat-ures,remains an understudied area.In this study,Al-Si-Cu-Mg-Ni/20wt%SiC particles(SiCp)composites with varying Ni contents were prepared by using a semisolid stir casting method.The effect of Ni content on the dry sliding wear behavior of the prepared compos-ites was investigated through sliding tests at 25 and 350℃.Results indicated that theθ-Al_(2)Cu phase gradually diminished and eventually disappeared as the Ni content increased from 0wt%to 3wt%.This change was accompanied by the formation and increase inδ-Al_(3)CuNi andε-Al_(3)Ni phases in microstructures.The hardness and ultimate tensile strength of the as-cast composites improved,and the wear rates of the composites decreased from 5.29×10^(−4)to 1.94×10^(−4)mm^(3)/(N∙m)at 25℃and from 20.2×10^(−4)to 7×10^(−4)mm^(3)/(N∙m)at 350℃with the increase in Ni content from 0wt%to 2wt%.The enhancement in performance was due to the presence of strengthening network structures and additional Ni-containing phases in the composites.However,the wear rate of the 3Ni composite was approximately two times higher than that of the 2Ni composite due to the fracture and debonding of theε-Al_(3)Ni phase.Abrasive wear,delamination wear,and oxidation wear were the predominant wear mechanisms of the investigated composites at 25℃,whereas delamination wear and oxid-ation wear were dominant during sliding at 350℃.

关键词： Al matrix composite microstructure sliding test high temperature wear mechanism

Single Image De-haze Based On a New Dark Channel Estimation Method

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Single Image De-haze Based On a New Dark Channel Estimation ...

High-tenacity in-situ Ti/Zr-based bulk metallic glasses composites fabricated by industrial high-pressure die casting

2012 IEEE International Conference on Computer Science and Automation Engineering（CSAE 2012）

作者： wenbo jin Zengyuan Mi Xiaotian Wu Yue Huang Xinghao Ding School of Information Science and Engineering Xiamen University Xiamen China

The image quality is effected dramatically by the weather conditions such as haze,fog and smoke in surveillance or vehicle systems.In this paper,we propose a novel algorithm to remove haze from a single image.A new dark channel estimation method is employed by subtracting three times variance from mean to approximate the minimum value,which is defined as the dark channel in a local area.To achieve anisotropic local mean and variance,a fast bilateral filter is introduced.Its complexity is a linear function of the size of the image,which makes real-time visibility restoration possible.Compared with existing algorithm based on dark channel prior,the proposed algorithm have better performance by reducing the halos introduced by large patches very well with less computational cost.

关键词： de-haze fog dark channel prior image restoration bilateral filter.

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Journal of Materials Science & Technology 2024年第3期170卷 177-185页

作者： Yang Li wenbo Luo Ying jin Zhiyong Xue Guiqing Wang Yanan Ren Haoxin Li Haibo Ke Baoan Sun Weihua Wang Institute for Advanced Materials North China Electric Power UniversityBeijing 102206China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The glass-forming ability and mechanical properties of metallic glasses and their composites are well known to be sensitive to the preparation conditions and are highly deteriorated by industrial preparing conditions such as low-purity raw materials and low vacuum.Here,we showed that a series of in-situ bulk metallic glass composites(BMGCs)which exhibit excellent ductility and segmental work hardening were successfully developed utilizing a high vacuum high-pressure die casting(HV-HPDC)technology along with industrial-grade raw materials.The tensile properties of these BMGCs are systematically investigated and correlated with the alloy microstructure.As compared with the copper mold suction casting method,the volume fraction difference of the dendrite phase for the BMGCs with the same composition is not significant when fabricated by the HV-HPDC,whereas the size of theβ-phase is generally larger.Insitu BMGCs with the composition of Ti_(48)Zr_(20)(V_(12/17)Cu_(5/17))19 Be 13 obtained by the HV-HPDC process show ductility up to 11.3%under tension at room temperature and exhibit a certain amount of work hardening.Two conditions need to be met to enable the BMGCs,which are prepared by vacuum die-casting to retain favorable ductility:(1)The volume fraction ofβphase stays below 62%±2%;(2)The equiaxed crystals with a more uniform size in the range of 5-10μm.Meanwhile,the results of the present study provided guidance for developing BMGCs with good ductile properties under industrial conditions.

关键词： Vacuum die casting Bulk metallic glass composites Mechanical properties β-phase

Development of advanced anion exchange membrane from the view of the performance of water electrolysis cell

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Journal of Energy Chemistry 2024年第3期90卷 348-369,I0009页

作者： Chao Liu Zhen Geng Xukang Wang Wendong Liu Yuwei Wang Qihan Xia wenbo Li Liming jin Cunman Zhang Clean Energy Automotive Engineering Center Tongji UniversityShanghai 201804China School of Automotive Studies Tongji UniversityShanghai 201804China

Green hydrogen produced by water electrolysis combined with renewable energy is a promising alternative to fossil fuels due to its high energy density with zero-carbon emissions.Among water electrolysis technologies,the anion exchange membrane(AEM) water electrolysis has gained intensive attention and is considered as the next-generation emerging technology due to its potential advantages,such as the use of low-cost non-noble metal catalysts,the relatively mature stack assembly process,etc.However,the AEM water electrolyzer is still in the early development stage of the kW-level stack,which is mainly attributed to severe performance decay caused by the core component,i.e.,AEM.Here,the review comprehensively presents the recent progress of advanced AEM from the view of the performance of water electrolysis cells.Herein,fundamental principles and critical components of AEM water electrolyzers are introduced,and work conditions of AEM water electrolyzers and AEM performance improvement strategies are discussed.The challenges and perspectives are also analyzed.

关键词： Hydrogen Water electrolysis Anion exchange membrane Electrolysis cell

Two-Dimensional Conductive Metal-Organic Framework Reinforced Spinterface in Organic Spin Valves

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CCS Chemistry 2024年第1期6卷 208-217页

作者： Xiaoyu Song Chao jin Hongliang Chen Shuaishuai Ding Zhongyi Liu Yang Li Xiaoli Yan wenbo Mi Long Chen Wenping Hu Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072 School of Chemistry and Chemical Engineering Yantai UniverisityYantaiShandong 264005 Tianjin Key Laboratory of Low Dimensional Materials Physics and Processing Technology School of ScienceTianjin UniversityTianjin 300072 State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunJilin 130012

Interface engineering in device fabrication is a significant but complicated issue.Although great successes have been achieved by conventional physical in situ or ex situ methods,it still suffers from complicated procedures.In this work,we present a facile method for fabricating phthalocyanine(Pc)-based two-dimensional conductive metal–organic framework(MOF)films.Based on PcM-Cu(M=Ni,Cu,H_(2))MOF films,spin valves with a vertical configuration of La_(0.67)Sr_(0.33)MnO_(3)/PcM-Cu MOFs/Co were constructed successfully,and exhibited notably high negative magnetoresistance(MR)up to -22% at 50 K.The penetrated Co atoms coordinated with the dehydrogenated hydroxy groups in the MOFs resulting in an antiferromagnetic layer of the PcM-Cu-Co hybrid structure.Interestingly,a significant exchange bias effect was demonstrated at the PcM-Cu MOF/Co interface,beneficial for the MR behavior.Thus,our present study provides new insights into developing high-performance organic spin valves via de novo molecular design.

关键词： two-dimensional conductive metal-organic framework two-dimensional polymer phthalocyanine spintronics organic spin valve

ROBUST RVM BASED ON SPIKE-SLAB PRIOR

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Journal of Electronics(China) 2012年第6期29卷 593-597页

作者： Ding Xinghao Mi Zengyuan Huang Yue jin wenbo School of Information Science and Technology Xiamen University

Although Relevance Vector Machine (RVM) is the most popular algorithms in machine learning and computer vision, outliers in the training data make the estimation unreliable. In the paper, a robust RVM model under non-parametric Bayesian framework is proposed. We decompose the noise term in the RVM model into two components, a Gaussian noise term and a spiky noise term. Therefore the observed data is assumed represented as: where is the relevance vector component, of which is the kernel function matrix and is the weight matrix, is the spiky term and is the Gaussian noise term. A spike-slab sparse prior is imposed on the weight vector which gives a more intuitive constraint on the sparsity than the Student's t-distribution described in the traditional RVM. For the spiky component a spike-slab sparse prior is also introduced to recognize outliers in the training data effectively. Several experiments demonstrate the better performance over the RVM regression.

关键词： Relevance Vector Machine (RVM) Bayesian nonparametric Outliers Spike-slab sparse prior

特大城市外洪内涝灾害链联防联控关键科学技术问题

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水科学进展 2023年第2期34卷 172-181页

作者：刘家宏梅超刘宏伟房小怡倪广恒靳文波中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038 水利部数字孪生流域重点实验室北京100038 南京水利科学研究院水文水资源与水利工程科学国家重点实验室江苏南京210029 中国气象科学研究院气象影响与风险研究中心北京100081 清华大学水沙科学与水利水电工程国家重点实验室北京100084 应急管理部大数据中心北京100013

近年来,特大城市极端暴雨内涝和流域洪水叠加导致的洪涝灾害风险呈增加趋势,造成了重大人员伤亡和财产损失,亟待开展流域洪水和城市内涝灾害链联防联控研究。融合气象科学、水文科学、信息科学、防灾减灾科学等多学科理论与方法,重点解... 详细信息

近年来,特大城市极端暴雨内涝和流域洪水叠加导致的洪涝灾害风险呈增加趋势,造成了重大人员伤亡和财产损失,亟待开展流域洪水和城市内涝灾害链联防联控研究。融合气象科学、水文科学、信息科学、防灾减灾科学等多学科理论与方法,重点解决城市外洪内涝组合致灾机理与灾害链风险传递规律关键科学问题;突破流域-城市一体化协同监测与早期风险感知技术、城市外洪内涝链生灾害智能预警与定向发布技术、跨尺度洪涝耦合模拟与联合防控场景推演技术、城市洪涝联防联控应急预案编制与智能化决策技术等4项关键技术。构建以空天地气象水文协同观测、社会经济多源信息汇聚分析、灾害动力模型推演为基础的联防联控应急指挥决策业务系统,突出实时性、动态化、精准性和智能化,支撑特大城市外洪内涝全过程预报、预警、预演、预案“四预”业务实践。

关键词：流域洪水城市内涝灾害链联防联控 “四预”措施

Multifrequency Networking Solution for TD-SCDMA

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ZTE Communications 2011年第1期9卷 41-44页

作者： Min jin wenbo Wang Mugen Peng Key Lab of National Education Ministry for Pan-Network Wireless Communication Beijing University of Posts and Telecommunications

This paper introduces the characteristics of TD-SCDMA, and analyzes some networking schemes and methods of multifrequency. For the 5 MHz frequency bandwidth, a frequency planning scheme containing three frequencies is examined, and a simulation model is built to validate the performance of this scheme. Finally, this paper analyzes the advantages and disadvantages of the scheme, and proposes some directions for the future study of networking planning.

关键词： TD-SCDMA multifrequency networking simulation frequency planning multi-frequency