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Journal of Materials Science & Technology 2017年第11期33卷 1255-1262页

作者： Zhaoyang Jin Kai Yin Kai Yan defeng wu Juan Liu Zhenshan Cui School of Mechanical Engineering Yangzhou University Yangzhou 225127 China School of Chemistry & Chemical Engineering Yangzhou University Yangzhou 225127 China Nationai Die and Mold CAD Engineering Research Center Shanghaifiao Tong University Shanghai 200030 China

Based on the principle of piecewise linearization, the incremental forms of microstructure evolution models were integrated into the thermo-mechanical coupled finite element（FE） model to simulate nonlinear microstructure evolution during multi-pass hot deformation. This is an unsteady-state deformation where dynamic recrystallization（DRX）, meta-dynamic recrystallization（MDRX）, static recrystallization（SRX） and grain growth（GG） take place during hot deformation or deformation interval. The distributions of deformation and microstructure for cylindrical AZ31 sample during single-pass and double-pass hot compressions were quantitatively calculated and compared with the metallographic observation. It is shown that both the deformation and microstructure are non-uniformly distributed due to the presence of friction between the die and the flat end of sample. The average grain size and its standard deviation under the double-pass hot compression are slightly smaller than those under single-pass *** simulated average grain sizes agree well with the experiments, which validates that the developed FE model on the basis of incremental forms of microstructure evolution models is reasonable.

关键词： Incremental method Microstructure evolution Multi-pass hot compression Finite element method Magnesium alloys

An Emulating Environment for Network Management of Space Network

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wuhan University Journal of Natural Sciences 2006年第2期11卷 365-369页

作者： ZHANG Jun HUANG Yingjun LI Guohui wu defeng School of Information System and Management National University of Defense Technology Changsha 410073 Hunan China Institute of Software Chinese Academy of Sciences Beijing 100080 China

An emulating environment for network management of the space network was presented. The emulating environment was developed with node-link model. The nodes of the satellite entities were controlled by the controlling network, which consist of sets of HLA/RTI based federates. These federates described the different aspect of the attributes of the satellites, such as orbit coordinate, routing table and the chain budget. We described the architecture of the emulation environment and the software design of federates. We measured the response time of the protocol data units and verified the detecting of the network topology in the environment. The environment was open that the on board router and the simulator of satellite link which developed by third party could be integrated.

关键词： space network emulating network management HLA/RTI (High Level Architecture/Runtime infrastructure)

基于深度神经网络的工业网络安全态势感知方法设计

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自动化与仪器仪表 2024年第7期 148-151页

作者：吴德峰祁志荣郑乾坤中安联合煤化有限责任公司安徽淮南232090

工业网络时刻面临着来自网络中的各种攻击入侵风险,为保护工业网络安全,设计一种基于深度神经网络的工业网络安全态势感知方法。该设计中通过数据仓库集成技术集成深度神经网络输入所需要的态势信息并实施处理,利用层次分析法从基础信... 详细信息

工业网络时刻面临着来自网络中的各种攻击入侵风险,为保护工业网络安全,设计一种基于深度神经网络的工业网络安全态势感知方法。该设计中通过数据仓库集成技术集成深度神经网络输入所需要的态势信息并实施处理,利用层次分析法从基础信息中提取关键态势要素,以关键态势要素为输入,利用深度神经网络计算工业网络安全态势值并划分安全态势等级。结果表明:随着攻击的进行,工业网络安全态势值呈现上升的趋势,其中U2R攻击下的态势值从最初0.32上升到了0.86,态势等级从安全发展到了高风险;DDos攻击下态势值从0.47上升到了0.55,态势等级从安全发展到了中等风险;Porbe攻击下态势值变化不明显,态势等级一直处在安全级别,由此说明该工业网络针对Porbe攻击防护能力最强,针对U2R攻击防护能力最弱。

关键词：深度神经网络工业网络安全态势感知方法

Estimating soil ammonium adsorption using pedotransfer functions in an irrigation district of the North China Plain

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Pedosphere 2021年第1期31卷 157-171页

作者： Chunying WANG defeng wu Xiaomin MAO Jingming HOU Lei WANG Yuping HAN Snate Key Labonatory of Eco fhydrnoudics in Norhwest Arid Region Xi'an Unesity of Teckunology.Xi'an 710048China North China University of Wiater Resoures and Electric Puwer Zhengzhow 450045 China College of Wanter Couseriangy and Civil Engineening China Agricndnuml Unersiny.Beijing 100083China Heman Key Labrratory of Water Re soures Comsenation and lueestive Uilization in the Hellow River Basin Zhengzhou 450046China

Extensive use of chemical fertilizers in agriculture can induce high concentration of ammonium nitrogen(NH4^(+)_(-)N) in soil. Desorption and leaching of NH4^(+)_(-)N has led to pollution of natural waters. The adsorption of NH4^(+)_(-)N in soil plays an important role in the fate of the NH4^(+)_(-)N. Understanding the adsorption characteristics of NH4^(+)_(-)N is necessary to ascertain and predict its fate in the soil-water environment, and pedotransfer functions(PTFs) could be a convenient method for quantification of the adsorption parameters. Ammonium nitrogen adsorption capacity, isotherms, and their influencing factors were investigated for various soils in an irrigation district of the North China Plain. Fourteen agricultural soils with three types of texture(silt, silty loam, and sandy loam) were collected from topsoil to perform batch experiments. Silt and silty loam soils had higher NH4^(+)_(-)N adsorption capacity than sandy loam *** and silt contents significantly affected the adsorption capacity of NH4^(+)_(-)N in the different soils. The adsorption isotherms of NH4^(+)_(-)N in the 14 soils fit well using the Freundlich, Langmuir, and Temkin models. The models’ adsorption parameters were significantly related to soil properties including clay,silt, and organic carbon contents and Fe^(2+) and Fe^(3+) ion concentrations in the groundwater. The PTFs that relate soil and groundwater properties to soil NH4^(+)_(-)N adsorption isotherms were derived using multiple regressions where the coefficients were predicted using the Bayesian method. The PTFs of the three adsorption isotherm models were successfully verified and could be useful tools to help predict NH4^(+)_(-)N adsorption at a regional scale in irrigation districts.

关键词： adsorption capacity adsorption isotherm ammonium nitrogen groundwater quality soil properties

Cathodic electrolysis method of depositing cerium conversion films on industrial pure aluminum

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Rare Metals 2002年第2期21卷 95-100页

作者： ZHANG Wei, LI Jiuqing, wu Yinshun, SHEN defeng, and HE JianpingDepartment of Surface Science & Corrosion Engineering, University of Science and Technology Beijing, Beijing 100083, China Department of Surface Science & Corrosion Engineering University of Science and Technology Beijing 北京 100083

Two two-step techniques, called TS2/TS7 and TS3/TS7, respectively,have been developed to form cerium conversion films on the surface ofindustrial pure aluminum. The tested material was cathodicallyelectrolyzed in the al- kaline solution containing cerium salt, anduniform films containing cerium were obtained after the two-steptreatment. It is found that the films obtained by TS2/TS7 and TS3/TS7techniques are about 4.0 and 3.0 um in thickness, respectiv- Ely. Thematerial has better corrosion resistance in the chloride solutionafter the two-step electrolysis treatent compar- Ed with the one-steptreated and naked specimens.

关键词： aluminum alloy rare earth conversion film cathodic electrochemicaldeposition

Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors

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International Journal of Mining Science and Technology 2024年第2期34卷 211-225页

作者： Xingsen Guo Ning Fan defeng Zheng Cuiwei Fu Hao wu Yanjun Zhang Xiaolong Song Tingkai Nian State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Environmentaland Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUnited Kingdom Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province Wenzhou 325035China Zhejiang International Science and Technology Cooperation Base of Ultra-soft Soil Engineering and Smart Monitoring Wenzhou 325035China School of Geography Liaoning Normal UniversityDalian 116029China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an 710043China Department of Geotechnical Engineering Nanjing Hydraulic Research InstituteNanjing 210024China wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China

Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental ***,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine *** incidents have highlighted the substantial damage to pipelines due to ***,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant *** assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline *** study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact *** factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of ***,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with *** upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.

关键词： Deep-sea fluidized slides Pipes Impact forces Shear behavior of slides Interface contact conditions Spatial relation

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三维表面扫描机器人本体的最优形位标定方法

机械工程学报 2013年第17期49卷 130-136页

作者：吴德烽李爱国集美大学轮机工程学院厦门361021 大连海事大学自动化研究中心大连116026

提高三维表面扫描机器人的本体定位精度是其用于制造加工质量控制的关键,提出一种基于三坐标测量机和二进制人工蜂群(Binary artificial bee colony,BABC)算法优化的机器人本体最优形位标定方法。该方法设计并加工一个测量转接件,利用... 详细信息

提高三维表面扫描机器人的本体定位精度是其用于制造加工质量控制的关键,提出一种基于三坐标测量机和二进制人工蜂群(Binary artificial bee colony,BABC)算法优化的机器人本体最优形位标定方法。该方法设计并加工一个测量转接件,利用三坐标测量机获得在多个机器人位姿下的转接件上精确的球心坐标,同时通过串口获得机器人的6个关节角度值。利用机器人的辨识雅可比矩阵,建立机器人运动学本体最优形位标定的目标函数,通过所提出的具有约束条件的BABC优化得到机器人运动学标定的最优形位,得到实际的机器人D-H参数。将最优形位标定获得的实际D-H参数和随机测量形位标定所得到的实际D-H参数应用于修正后的机器人运动学模型,由未参与计算的验证点数据表明,将所提出的BABC应用于机器人最优形位标定后,机器人的标定效果优于随机测量形位标定的方法。

关键词：机器人最优形位三坐标测量机人工蜂群算法

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三维表面扫描机器人误差建模与补偿方法

机械工程学报 2012年第13期48卷 61-67页

作者：吴德烽李爱国集美大学轮机工程学院厦门361021 大连海事大学自动化研究中心大连116026

对于三维表面扫描机器人系统,整个系统的测量误差主要来源于如下几个环节:机器人的本体定位误差、线结构光传感器的数据采集误差和手眼矩阵带来的误差。对于以上环节的各个部分,可以看成是局部过程。不论各个环节或部分的误差为多大,最... 详细信息

对于三维表面扫描机器人系统,整个系统的测量误差主要来源于如下几个环节:机器人的本体定位误差、线结构光传感器的数据采集误差和手眼矩阵带来的误差。对于以上环节的各个部分,可以看成是局部过程。不论各个环节或部分的误差为多大,最后的误差均归结于所得到的测量数据。然而,整个系统的误差模型很难通过解析方法得到。为了提高系统的测量精度,通过微粒群径向基神经网络建立系统的误差模型,网络的输入选择激光条纹图像坐标系中的坐标,输出选择为经过迭代最近点算法配准后的最近点与测量点之间的误差。利用微粒群算法优化初始所得的神经元中心和宽度,在相同网络性能的前提下,压缩了网络的规模。在测量过程中利用所建立的误差网络模型将测量误差得以补偿,通过实际的试验验证该方法提高系统测量精度的有效性。

关键词：三维表面扫描机器人误差建模与补偿微粒群径向基神经网络

聚苯硫醚/四氧化三铁复合材料的力学和磁性能

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化工学报 2008年第11期59卷 2941-2945页

作者：吴兰峰吴德峰张明扬州大学化学化工学院江苏扬州225002 江苏省环境材料与工程重点实验室江苏扬州225002

采用熔融共混的方法制备了聚苯硫醚(PPS)/四氧化三铁(Fe3O4)复合材料,考察了复合材料的形态、力学性能及磁性能。结果表明,均匀分散的Fe3O4粒子与PPS基体界面结合紧密;与纯PPS相比,复合体系在拉伸和弯曲强度显著提高的同时,冲击性能也... 详细信息

采用熔融共混的方法制备了聚苯硫醚(PPS)/四氧化三铁(Fe3O4)复合材料,考察了复合材料的形态、力学性能及磁性能。结果表明,均匀分散的Fe3O4粒子与PPS基体界面结合紧密;与纯PPS相比,复合体系在拉伸和弯曲强度显著提高的同时,冲击性能也有所改善;但过多的Fe3O4填充量反而不利于材料力学性能的提升。此外,复合体系的磁性仅依赖于Fe3O4的含量,而与Fe3O4的分散程度无关;因此,要获得既具有良好力学性能,又具有较高磁性的复合材料,30%(质量)左右的Fe3O4填充量较为适宜。

关键词：聚苯硫醚四氧化三铁复合材料力学性能磁性

聚己内酯/聚乳酸共混体系的相形态及其流变行为

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化工学报 2008年第10期59卷 2644-2649页

作者：张义盛吴德峰张明扬州大学化学化工学院

通过熔融共混制备了生物可降解的聚己内酯(PCL)/聚乳酸(PLA)共混体系,采用扫描电镜(SEM)和旋转流变仪分别研究了共混体系不相容的相形态及结构流变学。结果表明,共混体系的相形态强烈依赖于组分比。随PCL组分含量的增加,体系内部球形分... 详细信息

通过熔融共混制备了生物可降解的聚己内酯(PCL)/聚乳酸(PLA)共混体系,采用扫描电镜(SEM)和旋转流变仪分别研究了共混体系不相容的相形态及结构流变学。结果表明,共混体系的相形态强烈依赖于组分比。随PCL组分含量的增加,体系内部球形分散的形态逐渐向纤维状和部分双连续的相形态转变。两相界面的存在增加了体系动态弹性响应,并使体系出现了动态形状松弛。但从共混物模量对频率的依赖性仅能够判断体系是否存在不相容的相界面,相形态的差异则需通过松弛曲线来反映。

关键词：聚己内酯聚乳酸相形态流变行为