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Acta Mechanica Sinica 2025年第1期41卷 54-66页

作者： Jincai Chen Xiquan Wei Jingjing Huang Ding Fu haibo wang Zhideng Zhou School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China The State Key Laboratory of Nonlinear Machanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

Ship-bridge collisions happen from time to time globally, and the consequences are often catastrophic. Therefore, this paper pro-poses a new high-pressure water jet interference (HPWJI) method for bridge pier protection against vessel collision. Unliketraditional methods that absorb energy by anti-collision devices to mitigate the impact force of ships on bridges, this methodmainly changes the direction of ship movement by lateral high-pressure water jet impact, so that the ship deviates from the bridgepiers and avoids collision. This paper takes China’s Shawan River as the background and simulates the navigation of a ship(weighing about 2000 t) in the HPWJI method in the ANSYS-FLUENT software. The simulation results show that the HPWJImethod has a significant impact on the direction of the ship’s movement, enabling the ship to deviate from the pier, which istheoretically feasible for preventing bridge-ship collisions. The faster the ship’s speed, the smaller the lateral displacement anddeflection angle of the ship during a certain displacement. When the ship speed is less than 7 m/s, the impact of water flow onthe ship’s trajectory is more significant. Finally, this paper constructs a model formula for the relationship between the lateraldisplacement and speed, and surge displacement of the selected ship. This formula can be used to predict the minimum safedistance of the ship at different speeds.

关键词： Ship-bridge collision Anti-collision device Water jet Safe distance

光学智能反射表面辅助的UAV群分布式光移动通信

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电子与信息学报 2025年第1期47卷 48-56页

作者：王海卜张在琛葛荧萌曾涵东南大学移动通信国家重点实验室南京211189 紫金山实验室南京211111

随着无人机(UAV)系统的规模持续扩大以及对更高通信速率的需求增长,UAV光移动通信(UAV-OMC)已经成为一个有前景的技术方向。然而,传统的UAV-OMC难以支持多UAV之间的通信。该文基于光学智能反射表面(OIRS)技术,提出一个适用于UAV群的分布... 详细信息

随着无人机(UAV)系统的规模持续扩大以及对更高通信速率的需求增长,UAV光移动通信(UAV-OMC)已经成为一个有前景的技术方向。然而,传统的UAV-OMC难以支持多UAV之间的通信。该文基于光学智能反射表面(OIRS)技术,提出一个适用于UAV群的分布式OMC系统。通过在特定的UAV上设置OIRS,利用OIRS将光信号从单个UAV节点扩散到多个UAV节点。这一系统在保留UAV-OMC系统的高能效和高速度的同时,能够支持分布式UAV群的通信。对所提出的系统进行了数学建模,考虑了一系列现实因素,如OIRS的光束控制、UAV之间的相对运动和UAV的抖动等,这些因素都符合实际系统的特点。此外,该文还推导出了系统的误比特率(BER)和渐进中断概率的闭式表达式。基于理论分析和模拟结果,讨论了各个参数和系统设计的影响。

关键词：光移动通信光学智能反射表面无人机性能分析

The control of red water occurrence and opportunistic pathogens risks in drinking water distribution systems:A review

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Journal of Environmental Sciences 2021年第12期33卷 92-98页

作者： haibo wang Chun Hu Baoyou Shi Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of EducationInstitute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China

Many problems in drinking water distribution systems(DWDSs)are caused by microbe,such as biofilm formation,biocorrosion and opportunistic pathogens *** iron release from corrosion scales may induce red *** played great roles on the *** iron-oxidizing bacteria(IOB)promoted ***,when iron-reducing bacteria(IRB)and nitrate-reducing bacteria(NRB)became the main bacteria in biofilm,they could induce iron redox cycling in corrosion *** process enhanced the precipitation of iron oxides and formation of more Fe3 O4 in corrosion scales,which inhibited corrosion ***,the IRB and NRB in the biofilm can reduce iron release and red water ***,there are many opportunistic pathogens in biofilm of *** opportunistic pathogens growth in DWDSs related to the bacterial community changes due to the effects of *** increased the number of bacteria with antibiotic resistance genes(ARGs).Furthermore,extracellular polymeric substances(EPS)production was increased by the antibiotic resistant bacteria,leading to greater bacterial aggregation and adsorption,increasing the chlorine-resistance capability,which was responsible for the enhancement of the particle-associated opportunistic pathogens in ***,O3-biological activated carbon filtration-UV-Cl2 treatment could be used to control the iron release,red water occurrence and opportunistic pathogens growth in DWDSs.

关键词： Biofilm Iron release Red water Opportunistic pathogens Drinking water distribution systems

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压力管道非全周向裂纹涡流检测研究

机械设计与制造 2025年第1期407卷 236-239页

作者：王海波蔡佳宝侯哲生吉林化工学院机电工程学院吉林吉林132022 吉林省秸秆原料化工程研究中心吉林吉林132022

压力管道是工业生产过程中广泛使用的结构,裂纹是其常见缺陷,如何简单、快速检测出裂纹参数非常重要,涡流检测是一种清洁、环保和快速的检测方法。结合压力管道的特点,分析了其裂纹检测数学模型,采用有限元仿真的方法,对非全周向裂纹模... 详细信息

压力管道是工业生产过程中广泛使用的结构,裂纹是其常见缺陷,如何简单、快速检测出裂纹参数非常重要,涡流检测是一种清洁、环保和快速的检测方法。结合压力管道的特点,分析了其裂纹检测数学模型,采用有限元仿真的方法,对非全周向裂纹模型进行了分析,得出了压力管道周向不同裂纹长度和不同裂纹深度条件下的远场涡流检测信号特点,与实验结果对比,在误差范围内,仿真结果与实验结果一致,验证了有限元仿真方法的合理性,为涡流检测压力管道非全周向裂纹的研究打下了一定的基础。

关键词：压力管道非全周向裂纹涡流

Prediction and Verifcation of Forming Limit Diagrams Based on a Modifed Shear Failure Criterion

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 364-373页

作者： haibo wang Zipeng wang Yu Yan Yuanhui Xu School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The forming limit diagram plays an important role in predicting the forming limit of sheet *** studies have shown that,the method to construct the forming limit diagram based on instability theory of the original shear failure criterion is efective and *** original shear instability criterion can accurately predict the left area of the forming limit diagram but not the right *** this study,in order to improve the accuracy of the original shear failure criterion,a modifed shear failure criterion was proposed based on in-depth analysis of the original shear failure *** detailed improvement strategies of the shear failure criterion and the complete calculation process are *** on the modifed shear failure criterion and diferent constitutive equations,the theoretical forming limit of TRIP780 steel and 5754O aluminum alloy sheet metals are *** comparing the theoretical and experimental results,it is shown that proposed modifed shear failure criterion can predict the right area of forming limit more reasonably than the original shear failure *** efect of the pre-strain and constitutive equation on the forming limits are also analyzed in *** modifed shear failure criterion proposed in this study provides an alternative and reliable method to predict forming limit of sheet metals.

关键词： Modifed shear failure criterion Sheet metal forming Forming limit diagram Loading path

Forming limit of sheet metals based on mixed hardening model

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Science China(Technological Sciences) 2009年第5期52卷 1202-1211页

作者： haibo wang Min Wan School of Mechanical Engineering and Automation Beihang University Beijing 100191 China

The calculation method of forming limit of sheet metals based on M-K instability theory is proposed,and the method is applicable to different yield criterions and hardening *** forming limit dia-grams of AA5754-O,AA6111-T4 aluminum alloy sheet and DP steel sheet under combined loading paths are obtained based on mixed hardening model with YLD2000-2D yield criterion proposed by Barlat in 2003 and L-C nonlinear kinematic hardening model proposed by Lemaitre and *** results show that the forming limit diagram made up of limit strain(FLD-strain) is evidently influenced by the loading *** forming limit diagram made up of limit stress(FLD-stress) is also influenced by loading path and it is not an only curve,which differs from the conventional *** degree of the influence of loading path on FLD-stress is related with *** larger the pre-strain is,the greater the influence of loading path on FLD-stress will *** change of FLD-stress is small only when pre-strain is *** addition,the hardening behavior of the material will influence the path-dependence of FLD-stress:The larger the proportion of kinematic hardening in the whole hard-ening is,namely the more obvious Bauschinger effect of the material,the greater the influence of loading path on FLD-stress will be.

关键词： plastic forming of sheet metals forming limit hardening model complex loading path

3D-Flair MRI和前庭功能在极重度突发性聋患者预后评估中的应用

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中华耳鼻咽喉头颈外科杂志 2025年第1期60卷 2-9页

作者：戴清蕾熊文萍王英俊胡娜孙晓樊兆民王海波王明明山东大学山东省耳鼻喉医院耳内科济南250022 山东大学山东省耳鼻喉医院医学影像中心济南250022 山东大学山东省耳鼻喉医院耳科中心济南250022

目的分析极重度突发性聋患者的内耳三维液体衰减反转恢复(three dimensional fluid attenuated inversion recovery,3D-Flair)MRI表现、前庭功能情况及其与预后的相关性,探讨突发性聋可能的预后评估指标。方法回顾性分析2018年3月至2020... 详细信息

目的分析极重度突发性聋患者的内耳三维液体衰减反转恢复(three dimensional fluid attenuated inversion recovery,3D-Flair)MRI表现、前庭功能情况及其与预后的相关性,探讨突发性聋可能的预后评估指标。方法回顾性分析2018年3月至2020年8月山东省耳鼻喉医院耳内科住院的成人单侧极重度突发性聋患者的临床资料。根据患者内耳3D-Flair MRI的结果分为MRI正常组和异常组,异常组又分为内耳高信号未吸收、高信号吸收和血迷路屏障破坏三组。应用SPSS 26.0统计软件分析各组患者听力疗效、冷热实验、前庭诱发肌源性电位(VEMP)、视频头脉冲试验(vHIT)以及头晕/眩晕伴发率的差异。结果共收集资料完整患者191例(男97例,女94例,年龄13~69岁),其中内耳3D-Flair MRI正常组50例,异常组共141例(包括内耳高信号未吸收组50例,内耳高信号吸收组71例,血迷路屏障破坏组20例)。四组间年龄、性别、耳聋侧别和病程差异均无统计学意义(P值均>0.05)。治疗后听力疗效比较,内耳3D-Flair MRI正常组的显效率和总有效率均高于异常组,差异具有统计学意义(P值均<0.05)。四组间比较,正常组和内耳高信号吸收组的显效率和总有效率差异具有统计学意义(χ^(2)=4.007,P=0.045;χ^(2)=6.925,P=0.009)。内耳3D-Flair MRI异常组的冷热试验、vHIT结果异常率及头晕/眩晕症状的发生率均高于正常组,差异具有统计学意义(P值均<0.05);MRI异常的三组间眼肌前庭诱发肌源性电位(oVEMP)异常率、vHIT异常率、伴头晕/眩晕发生率差异均有统计学意义(P值均<0.05);四组间冷热试验、oVEMP异常率、vHIT异常率、头晕/眩晕发生率差异均有统计学意义(P值均<0.05)。伴头晕/眩晕患者的冷热试验、颈肌前庭诱发肌源性电位(cVEMP)、vHIT阳性率,均高于不伴头晕/眩晕患者,差异具有统计学意义(P值均<0.05);伴头晕/眩晕患者的vHIT后半规管和水平半规管的异常率显著增高,与不伴头晕/眩晕患者相比差异具有统计学意义(P值均<0.05);不伴头晕/眩晕患者的痊愈率、有效率和总有效率均明显高于伴头晕/眩晕患者,差异具有统计学意义(P值均<0.05)。结论内耳3D-Flair MRI和前庭功能检查对极重度突发性聋患者的预后评估具有参考价值。内耳3D-Flair MRI异常,尤其是内耳高信号吸收者,前庭功能异常和头晕/眩晕伴发率高,预后差。伴头晕/眩晕症状极重度突发性聋患者更易出现前庭功能检查结果异常,其后半规管和水平半规管更易受累。

关键词：听觉丧失,突发性磁共振成像前庭功能试验眩晕头晕

Variations and drivers of aerosol vertical characterization after clean air policy in China based on 7-years consecutive observations

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Journal of Environmental Sciences 2023年第3期125卷 499-512页

作者： Xi Chen Ting Yang haibo wang Futing wang Zifa wang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Understanding the aerosol vertical characterization is of great importance to both climate and atmospheric environment. This study investigated the variations of aerosol profiles over eight regions of interest in China after clean air policy(2013-2019) and discussed the drivers of the vertical aerosol structure, using observations from active satellite measurements(CALIPSO). From the annual variation, the amplitude of extinction coefficient profiles showed a decreasing trend with fluctuations, and the maximum was 0.21 km-1in BeijingTianjin-Hebei(JJJ). For regions suffered from air pollution, the variation was greatest below 0.45 km, while it was between 1-1.5 km for Sichuan Basin. The correlation coefficient between the relative humidity(RH) and the extinction coefficient indicated that the increase of RH inhibited the decrease of the extinction coefficient in the Yangtze River Delta. In most regions, the main aerosol subtypes were polluted dust and polluted continental, but they were coarser in JJJ and North West. The frequency of concurrency of dust and polluted dust aerosols decreased in JJJ, but polluted continental aerosols occurred more frequently. Further, the aerosol extinction coefficient profiles under different pollution conditions showed that it changed most during heavy pollution periods in JJJ, especially in 2017, with a significant aerosol loading between700 and 1200 m. The atmospheric reanalysis data revealed that the weak convergence at low level and the divergence at high level supported the upward transport of aerosols in 2017. Overall, the differences in divergence allocation, RH, and wind filed were the main meteorological drivers.

关键词： Aerosol Vertical characteristic China CALIPSO Pollution period

Evaluation of external costs in road transport under the openness of a gated community

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Frontiers of Earth Science 2020年第1期14卷 140-151页

作者： Ming CAI Jing LI Zhanyong wang haibo wang Guangdong Provincial Key Laboratory of Intelligent Transportation System School of Intelligent Systems EngineeringSun Yat-Sen UniversityGuangzhou 518107China College of Transportation and Civil Engineering Fujian Agriculture and Forestry UniversityFuzhou 350108China School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China

Residential quarters in Chinese cities are usually walled off from their surrounding roads for security ***,the Chinese government has decided to thoroughly open gated residential communities in order to improve traffic capacity and coordinate major roads in the road network,which will inevitably pose challenges,such as environmental pollution,for community ***,before this decision,there were no comprehensive investigations into whether this measure works for road traffic or how much the adverse impact exerts upon ***,we propose a comprehensive method combining microscopic traffic simulation with a vehicle exhaust emission and dispersion model and a noise emission and attenuation model,in addition to a consideration of social cost,to evaluate the possible influence of opening an enclosed residential community to surrounding *** validity of the hybrid model was assessed by an assumptive case of two rectangular gated communities under varying traffic flow and five community opening *** results indicate that the opened community outperforms the gated in the most of 49 percent reduction in comprehensive cost.A more detailed analysis reveals that the appropriate extent of openness should rely on the actual situation,and potentially serves as a foundation for the healthy development of communities and *** on the case study results,this paper outlines some strategical suggestions for improving enclosed residential areas by striking a better balance between traffic capacity and environmental risks.

关键词： road traffic social cost externality gated residential area

An optimized staggered variable-grid finite-difference scheme and its application in cross-well acoustic survey

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Chinese Science Bulletin 2008年第6期53卷 825-835页

作者： ZHAO haibo wang XiuMing Institute of Acoustics Chinese Academy of Sciences Beijing 100080 China

In this paper, an optimized staggered variable-grid finite-difference (FD) method is developed in veloc- ity-stress elastic wave equations. On the basis of the dispersion-relation-preserving (DRP), a fourth-order finite-difference operator on non-uniform grids is constructed. The proposed algorithm is a continuous variable-grid method. It does not need interpolations for the field variables between re- gions with the fine spacing and the coarse one. The accuracy of the optimized scheme has been veri- fied with an analytical solution and a regular staggered-grid FD method for the eighth order accuracy in space. The comparisons of the proposed scheme with the variable-grid FD method based on Taylor series expansion are made. It is demonstrated that this optimized scheme has less dispersion errors than that with Taylor's series expansion. Thus, the proposed scheme uses coarser grids in numerical simulations than that constructed by the Taylor's series expansion. Finally, the capability of the opti- mized FD is demonstrated for a complex cross-well acoustic simulation. The numerical experiment shows that this method greatly saves storage requirements and computational time, and is stable.

关键词：声波测量有限差分法可变栅格弹性波