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Plasma Science and Technology 2024年第9期26卷 97-108页

作者： Bingyan CHEN Qi LIU Xu LI Chunyang ZHANG Xiangbin GUO Qingzhou YU Zhicheng TANG Xiang HE wei SU Yongfeng JIANG college of Mechanics and engineering Science Hohai UniversityNanjing 211100People’s Republic of China college of mechanical and electrical engineering Hohai UniversityChangzhou 213200People’s Republic of China college of Materials Science and engineering Hohai UniversityChangzhou 213200People’s Republic of China college of Information Science and engineering Hohai UniversityChangzhou 213200People’s Republic of China

The present work investigates the potential applications of nitrogen oxides(NO_(x)),particularly nitric oxide(NO)and nitrogen dioxide(NO_(2)),generated through discharge plasma in diverse sectors such as medicine,nitrogen fixation,energy,and environmental *** this study,a rotating sliding arc discharge reactor was initially employed to produce high concentrations of gaseous NO_(x),followed by the utilization of a molybdenum wire redox reactor for NO_(2)-to-NO *** outcomes reveal that the discharge states and generations of NO_(x) are affected by varying parameters,including the applied energies,frequencies and airflow states(1.3-2.6 m/s are the laminar flow,2.6-5.2 m/s are the transition state,5.2-6.5 m/s are the turbulent flow),and the concentrations of NO_(x) within the arc discharge are higher than that in the spark ***,the concentrations of NO,NO_(2) and NO_(x) gradually increased,and the concentration ratios of NO/NO_(2) and NO_(x)/NO_(2) decreased with increasing the applied energy for one cycle from 14.8 mJ to 24.3 ***,the concentrations of NO,NO_(2) and NO_(x) gradually decreased,and the concentration ratios of NO/NO_(2) and NO_(x)/NO_(2) first decreased and then increased with increasing the applied frequencies from 5.0 kHz to 9.0 ***,the concentrations of NO,NO_(2) and NO_(x) gradually decreased,and the concentration ratios of NO/NO_(2) and NO_(x)/NO_(2) first increased and then decreased with increasing the air flow speeds from 1.3 m/s to 6.5 m/***,the concentrations of NO increased and NO_(2) decreased with increasing temperature from 25℃ to 400℃ using molybdenum *** findings provide experimental support for the application of plasma in the fields of medicine,nitrogen fixation,energy and environmental protection.

关键词： rotating sliding arc discharge NO_(x) synthesis of NO redox reaction

Microstructure and tensile properties of rapid-cooling friction-stir-welded AZ31B Mg alloy along thickness direction

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Transactions of Nonferrous Metals Society of China 2020年第12期30卷 3254-3262页

作者： Nan XU wei-da ZHANG Si-qi cai Yue ZHUO Qi-ning SONG Ye-feng BAO college of mechanical and electrical engineering Hohai UniversityChangzhou 213022China

Rapid-cooling friction-stir-welding(FSW)was used to join AZ31B magnesium alloy plates of 6 mm in *** microstructure and mechanical properties in thickness direction were carefully investigated with electron backscattered diffractometer,and transmission electron *** obtained results showed that ultrafine grains with high dislocation density were obtained in the top region of the weld due to liquid CO2 cooling.A large number of{1012}twins and second-phase particles were also induced in these refined *** basal texture intensity was significantly reduced due to the appearance of{1012}*** top region showed the higher strength and elongation compared with the bottom region,and the welding efficiency reached 93%.This work provided a simple and efficient strategy for manufacturing a gradient structure in the FSW Mg alloy joint.

关键词： friction stir welding magnesium alloy recrystallization texture microstructure mechanical properties

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旋流泵叶轮流道固液两相流动不稳定性分析

水道港口 2024年第2期45卷 282-290页

作者：李洪彬易伟倪福生河海大学机电工程学院常州213022 疏浚技术教育部工程研究中心常州213022 中水北方勘测设计研究有限责任公司天津300222

由于结构的特殊性以及固液两相存在的密度差,旋流泵在输送固液两相介质过程中,内部会出现多方面的不稳定性特征,基于Particle模型,运用ANSYS CFX软件对额定转速下旋流泵在不同流量下输送不同固相体积分数的多种工况进行了非定常数值模拟... 详细信息

由于结构的特殊性以及固液两相存在的密度差,旋流泵在输送固液两相介质过程中,内部会出现多方面的不稳定性特征,基于Particle模型,运用ANSYS CFX软件对额定转速下旋流泵在不同流量下输送不同固相体积分数的多种工况进行了非定常数值模拟,分析了叶轮流道内的固相分布、压力脉动和叶轮径向力,从而深入了解叶轮内部不稳定性。结果表明:在C_(v)=5%体积分数下,0.8 Q_(d)、1.0 Q_(d)流量下叶轮流道内固相体积分布均匀,1.2 Q_(d)分布不均匀;在C_(v)=10%体积分数下,0.8 Q_(d)流量下分布均匀,1.0 Q_(d)和1.2 Q_(d)流量下分布不均匀;在C_(v)=20%体积分数下,0.8 Q_(d)、1.2 Q_(d)流量下分布均匀,1.0 Q_(d)分布不均匀;在C_(v)=20%、1.0 Q_(d)工况的一个旋转周期内,叶轮内部始终存在一个条形固相分布区域,且其旋转速度滞后于叶轮旋转速度。在1.0 Q_(d)流量下,随着固相体积分数的增加,各监测点压力系数幅值波动逐步变大;后缩腔监测点叶频处的幅值基本不变,叶轮流道内监测点轴频处的幅值逐步变大;在C_(v)=20%体积分数下,随着流量的增加,各监测点压力系数幅值波动先增后减,后缩腔监测点叶频处幅值逐步增大,流道内监测点轴频处的幅值先增后减。相同固相体积分数下,随着流量的增加,径向力逐步增大;不同固相体积分数下,随着体积分数的增加,0.8 Q_(d)流量下径向力波动不大,1.0 Q_(d)流量下波动逐步变大,1.2 Q_(d)流量下波动逐步变小。

关键词：旋流泵固液两相压力脉动径向力

Optimization method for a radar situation interface from error-cognition to information feature mapping

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Journal of Systems engineering and Electronics 2022年第4期33卷 924-937页

作者： WU Xiaoli wei Wentao CALDWELL Sabrina XUE Chengqi WANG Linlin School of Design Art&Media Nanjing University of Science&TechnologyNanjing 210094China School of mechanical engineering Southeast UniversityNanjing 211189China college of mechanical and electrical engineering Hohai UniversityChangzhou 211100China School of Computer Science Australian National UniversityCanberra 2600Australia

With the rapid development of digital and intelligent information systems, display of radar situation interface has become an important challenge in the field of human-computer interaction. We propose a method for the optimization of radar situation interface from error-cognition through the mapping of information characteristics. A mapping method of matrix description is adopted to analyze the association properties between error-cognition sets and design information sets. Based on the mapping relationship between the domain of error-cognition and the domain of design information, a cross-correlational analysis is carried out between error-cognition and design *** obtain the relationship matrix between the error-cognition of correlation between design information and the degree of importance among design information. Taking the task interface of a warfare navigation display as an example, error factors and the features of design information are extracted. Based on the results, we also propose an optimization design scheme for the radar situation interface.

关键词： radar situation interface error-cognition information feature mapping visual information display

基于改进IVNSA的RGV/ASR仓储系统出入库调度算法

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机械设计与制造工程 2024年第4期53卷 87-93页

作者：王斌王巍王泰朱磊郭镇洋中盐金坛盐化有限责任公司江苏常州213251 河海大学机电工程学院江苏常州213251

针对自动化立体仓库(AS/RS)中环形穿梭车(RGV)和空中分拣机器人(ASR)协同调度问题,以最小化运输时间为目标,建立了RGV/ASR仓储系统的出入库问题调度模型,并提出改进变邻域搜索算法(IVNSA)对问题模型进行求解。首先,设计双序列编码方式... 详细信息

针对自动化立体仓库(AS/RS)中环形穿梭车(RGV)和空中分拣机器人(ASR)协同调度问题,以最小化运输时间为目标,建立了RGV/ASR仓储系统的出入库问题调度模型,并提出改进变邻域搜索算法(IVNSA)对问题模型进行求解。首先,设计双序列编码方式优化搜索空间;其次,针对任务调度顺序设计全局综合搜索算子,扩大了算法搜索空间,同时受生物体激素调控机制启发,提出一种基于生物体激素调控机制的局部深度搜索算子,提高了算法的局部搜索深度;最后,通过对比实验验证了所提算法的优越性和有效性。

关键词：自动化立体仓库 RGV/ASR仓储系统出入库调度全局综合搜索算子局部深度搜索算子

MCFNet:基于多模态特征交叉融合的水下目标识别网络

同方期刊数据库博看期刊评论

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无人系统技术 2024年第4期7卷 55-65页

作者：包宇航郑成伟魏长赟河海大学机电工程学院常州213200

在水声目标识别领域,现有识别方法主要采用基于时域或时频域技术,对环境噪声和干扰非常敏感,尤其在复杂多路径水声环境中,信号容易受到干扰,且仅依赖时域和时频域的特征难以准确描述复杂或相似目标的关键属性。对此,为进一步挖掘水声数... 详细信息

在水声目标识别领域,现有识别方法主要采用基于时域或时频域技术,对环境噪声和干扰非常敏感,尤其在复杂多路径水声环境中,信号容易受到干扰,且仅依赖时域和时频域的特征难以准确描述复杂或相似目标的关键属性。对此,为进一步挖掘水声数据信息,并充分利用时域与时频域特征,提出了基于多模态特征交叉融合的水声目标识别网络。首先,利用一维序列特征提取模块和以ResNet为主干网络的二维图像特征提取模块对水声数据进行粗提取。其次,为准确捕捉时域中时序信息,设计了一种时序注意力模块,实现对不同时间步的特征提取。接着,通过提出的特征融合模块实现多模态特征的融合,提升网络对多模态特征的提取能力,增强网络的特征表达能力。最后,在DeepShip数据集上进行验证,提出的水声目标识别网络取得98.80%的准确率,优于其他方法,证实了所提方法的有效性。

关键词：水声目标识别特征提取多模态特征融合信息交互深度学习目标分类

Deep-sea rock mechanics and mining technology:State of the art and perspectives

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International Journal of Mining Science and Technology 2023年第9期33卷 1083-1115页

作者： Zenghui Liu Kai Liu Xuguang Chen Zhengkuo Ma Rui Lv Changyun wei Ke Ma engineering Research Center of Dredging Technology of Ministry of Education College of Mechanical and Electrical EngineeringHohai UniversityChangzhou 213022China Department of engineering Science University of OxfordParks RoadOxford OX13PJUK college of engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Coastal and Offshore engineering Dalian University of TechnologyDalian 116024China

The review covers the development and the state of the art in deep-sea mining rock mechanics,equipment and *** begins by introducing the significance of deep-sea mining,the types and geographical distribution of deep-sea *** 2 reviews the mechanical properties and fracture mechanism of seabed and related continental rocks,which contributes to the advancement of relevant technologies and ***-sea mining systems developed by coastal countries are presented in Section *** mineral collection systems are critically assessed in Section *** mining vehicle is reviewed by walking mechanism and controlling system in Section *** Section 6,the development of subsea lifting system is detailed by dividing it into hydraulic and pneumatic lifting modes,and some technical problems in the lifting system are *** in-depth description of surface support systems is presented in Section 7,which includes the deep-sea mining ship,dynamic positioning system,heave compensation system,launch and retrieval system,mineral disposing system as well as the storage and transferring *** 8 discusses the challenges in the deep-sea mining,in terms of natural occurrence conditions,international legal framework and cooperative mining,environmental protection and economic benefits,***,a brief summary and some aspects of prospective research are presented in Section 9.

关键词： Deep-sea mining Deep-sea minerals Seabed mineral collection system Subsea mining vehicle Subsea lifting system

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基于随机力学理论的堤防安全分析方法综述

长江科学院院报 2019年第10期36卷 66-72,78页

作者：丁家怡蔡伟周建方河海大学力学与材料学院南京211100 河海大学机电工程学院江苏常州213022

近年来,基于随机力学理论的堤防安全分析方法已经得到了深入的研究和广泛的应用,但是目前仍然缺少对该方法系统性的总结说明。为对基于随机力学理论的堤防安全分析方法的主要内容及工程应用进行综述,介绍了3种堤防典型失事模式,分析了... 详细信息

近年来,基于随机力学理论的堤防安全分析方法已经得到了深入的研究和广泛的应用,但是目前仍然缺少对该方法系统性的总结说明。为对基于随机力学理论的堤防安全分析方法的主要内容及工程应用进行综述,介绍了3种堤防典型失事模式,分析了堤防安全分析中应该考虑的风险因素,并系统整理了风险因素的不确定性和相关性;总结了基于随机力学理论的各种常用的堤防安全分析方法,详述了其在3种堤防典型失事模式中的应用及适用性,重点阐述了基于随机场理论与考虑风险因素互相关性的堤防安全分析方法研究。基于随机力学理论的堤防安全分析方法的主要发展方向是开展基于随机场的有限元法研究,及风险因素间互相关性研究。

关键词：堤防安全随机力学风险因素互相关性随机场

附加质量法和FSI法用于弧形闸门动力特性分析的适用性

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中国港湾建设 2024年第1期44卷 1-6页

作者：胡友一王珏陆中伟郑赟河海大学机电工程学院江苏常州213022

为研究附加质量法和流固耦合界面(FSI)法用于弧形闸门动力特性分析的适用性,首先通过建立弧形闸门有限元模型,采用收敛性分析的方法研究了FSI法计算时流体长度的合理取值,保证了流体-弧形闸门系统自振频率的计算精度。其次,从弧形闸门... 详细信息

为研究附加质量法和流固耦合界面(FSI)法用于弧形闸门动力特性分析的适用性,首先通过建立弧形闸门有限元模型,采用收敛性分析的方法研究了FSI法计算时流体长度的合理取值,保证了流体-弧形闸门系统自振频率的计算精度。其次,从弧形闸门水头高度和刚度的角度出发,比较了采用附加质量法和FSI法对弧形闸门流固耦合效应的模拟结果,讨论了采用简化的附加质量法的适用性。最后,根据有限元计算的数值结果讨论了流固耦合效应对弧形闸门动力特性的影响。结果表明:(1)FSI法中流体长度取2倍水头高度可代替实际流体的无界性;(2)在水头较低且闸门刚度较大的情况下,采用附加质量法模拟流固耦合效应能在保证计算精度的基础上提高计算效率。随着水头增高,精度有所下降。此时,弧形闸门的自振频率明显降低,并且主要的变形由支臂转移到面板,有必要采用FSI法代替附加质量法来确保计算精度。

关键词：弧形闸门流固耦合附加质量法 FSI法自振频率