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NiCoFeCrAl系高熵合金热加工图不同失稳判据比较

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稀有金属材料与工程 2024年第1期53卷 38-46页

作者：张允胜蒋学禹周舸张浩宇张思倩车欣陈立佳曹雪沈阳工业大学材料科学与工程学院辽宁沈阳110870 沈阳工业大学沈阳市先进结构材料与应用重点实验室辽宁沈阳110870 中国航发北京航空材料研究院北京100095

采用Gleeble-3800热模拟试验机对NiCoFeCrAl系高熵合金进行单道次热压缩实验研究,根据峰值应力构建了NiCoFeCrAl系高熵合金Arrhenius本构关系模型,运用Prasad、murty、gegel和malas四种失稳准则,构建了不同失稳判据下的Dmm热加工图,并... 详细信息

采用Gleeble-3800热模拟试验机对NiCoFeCrAl系高熵合金进行单道次热压缩实验研究,根据峰值应力构建了NiCoFeCrAl系高熵合金Arrhenius本构关系模型,运用Prasad、murty、gegel和malas四种失稳准则,构建了不同失稳判据下的Dmm热加工图,并对不同失稳判据在该合金热变形过程中的适用范围进行了分析与比较,确定了该合金的最佳热加工区间为温度为980~1010℃+应变速率为0.01~0.001s^(-1)和温度范围为1050~1100℃+应变速率为0.01~0.1s^(-1),平均功率耗散率大于36%。借助EBSD显微组织分析,确定了热变形的软化机制随变形量的增大由动态回复向动态再结晶转变。

关键词：高熵合金失稳判据热变形行为 Arrhenius本构方程变形组织

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基于场矩阵分解机和CNN的点击率预测模型

计算机系统应用 2024年第1期33卷 87-98页

作者：王志格李汪根夏义春高坤束阳葛英奎安徽师范大学计算机与信息学院芜湖241002

点击率预测是在线广告和推荐系统的基本任务之一.主流模型通常通过对高阶和低阶特征进行特征交互建模来提升性能和泛化能力.然而,许多模型往往仅学习每个特征的固定表示,而忽视了特征在不同上下文中的重要性,并且一些模型结构过于简单.... 详细信息

点击率预测是在线广告和推荐系统的基本任务之一.主流模型通常通过对高阶和低阶特征进行特征交互建模来提升性能和泛化能力.然而,许多模型往往仅学习每个特征的固定表示,而忽视了特征在不同上下文中的重要性,并且一些模型结构过于简单.因此,本文提出了特征细化卷积神经网络融合场矩阵分解机(FRCNN-F)模型,以解决这些问题.首先,在特征细化网络(FRNet)中融合了卷积神经网络的特征生成模块,利用其在局部模式下重新组合生成新特征的优势,提升了重要特征选择能力.其次,设计了场矩阵分解机,使模型能够感知上下文并通过不同场的交互进行显示建模,从而增加了子模型的组合方式.最后,通过在Frappe和movieLens两个公开数据集上对比实验,实验结果表明,FRCNN-F模型相比基线FRNet在AUC得分分别提升了0.32%和0.40%,交叉熵损失函数Logloss分别降低了1.50%和1.11%.该研究对于实现广告的精准投放和个性化推荐具有实际应用的价值.

关键词：点击率预测特征交互特征细化网络卷积神经网络场矩阵分解机

The uptake of ethyl iodide on black carbon surface

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Chinese Science Bulletin 2008年第5期53卷 733-738页

作者： YIN Shi WANG WeiGang ge maoFa State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The importance of the iodine chemistry in the atmosphere has been demonstrated by recent observa- tions. The uptake of ethyl iodine on black carbon surface was investigated at 298 K for the first time. Degussa FW2 (an amorphous black carbon comprising medium oxides) was used as black carbon sample. Black carbon surface was found to be deactivated in reaction with C_2H_5I, and the uptake coef- ficient (γ ) was dependent on the time of exposure. The value of (2.3±0.9)×10^(-2) was determined for the initial uptake coefficient (γ0). The result suggests that the heterogeneous loss of C_2H_5I on carbonaceous aerosols may be important under the atmospheric conditions.

关键词：乙基碘炭黑吸收非均匀过程大气化学

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新型配电系统国际标准化现状与展望

标准科学 2024年第10期 37-44,49页

作者：蒋一博王喆朱婵霞单沫文程刘柯周格格国网(苏州)城市能源研究院 IEC国际标准促进中心(南京)

新型配电系统标准是新型配电系统技术发展总体战略的重要内容,对整个行业的发展起着有效的规范和引导作用,然而新型配电系统国际标准化工作还处于起步阶段,迫切需要我国根据国内新型配电系统标准发展与国际化现状,开展新型配电系统标准... 详细信息

新型配电系统标准是新型配电系统技术发展总体战略的重要内容,对整个行业的发展起着有效的规范和引导作用,然而新型配电系统国际标准化工作还处于起步阶段,迫切需要我国根据国内新型配电系统标准发展与国际化现状,开展新型配电系统标准国际化战略研究。本文首先对新型配电系统的关键特征和面临的技术挑战进行了梳理和分析,然后对目前主要的国际标准组织在新型配电系统领域相关国际标准的现状进行了分析和总结,最后对相关领域的国际标准化发展趋势进行了展望,为后续新型配电系统国际标准的制修订提供参考。

关键词：新型配电系统新能源并网国际标准化标准化展望

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Actuation Delay-Time Estimation with Imaging Fuze

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Journal of Beijing Institute of Technology 2017年第4期26卷 557-562页

作者： Yuzhao Li Zhiqiang ge Yan Liu Beijing Institute of Remote Sensing Equipment Beijing 100854 China

generally,Doppler fuze can only estimate actuation delay-time with a limited precision. As an improvement,imaging fuze can estimate actuation delay-time more precisely with the available two-dimensional image of the target. In this paper,imprecision of actuation delay-time estimation with Doppler fuze is first analyzed theoretically in brief. Secondly,feasibility analysis and theoretical model of imaging fuze are described,in which a criterion is established for the actuation delay-time based on the image,and then an image based gray-value weighted least square（ GWLS） algorithm is presented to calculate actuation delay-time of the imaging fuze. Finally,a simulation model of missiletarget near-field encounter is established. Simulation results indicate that actuation delay-time of the imaging fuze is estimated more precisely than by the Doppler fuze.

关键词： imaging fuze actuation delay-time guidance integrated fuzing (GIF)

The temperature record of the Holocene: progress and controversies

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Science Bulletin 2019年第9期64卷 565-566页

作者： Juzhi Hou Can-ge Li Shihyu Lee Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences University of Chinese Academy of Sciences Research Center for Environmental Change Academia Sinica

The pattern of temperature variation during the Holocene, the most recent geological epoch, has been studied intensively, partly because of its significance for the development of human civilization. Prior to the 1980s, based on ice core records in Greenland and Antarctica, the climate of the Holocene was thought to have been rather stable (1)However, this view was challenged by the discovery of a substantial amount of contrary evidence.

关键词： The temperature record of the Holocene progress and controversies

Webpage matching Based on Visual Similarity

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Computers, materials & Continua 2022年第5期71卷 3393-3405页

作者： mengmeng ge Xiangzhan Yu Lin Ye Jiantao Shi School of Cyberspace Science Harbin Institute of TechnologyHarbin150001China Department of Computer and Information Science Temple UniversityPhiladelphia42101USA

With the rapid development of the Internet,the types of webpages are more abundant than in previous ***,it becomes severe that people are facing more and more significant network security risks and enormous losses caused by phishing webpages,which imitate the interface of real webpages and deceive the *** better identify and distinguish phishing webpages,a visual feature extraction method and a visual similarity algorithm are ***,the visual feature extraction method improves the Visionbased Page Segmentation(VIPS)algorithm to extract the visual block and calculate its signature by perceptual hash ***,the visual similarity algorithm presents a one-to-one correspondence based on the visual blocks’coordinates and *** the weights are assigned according to the tree structure,and the similarity of the visual blocks is calculated on the basis of the measurement of the visual features’Hamming ***,the visual similarity of webpages is generated by integrating the similarity and weight of different visual ***,multiple pairs of phishing webpages and legitimate webpages are evaluated to verify the feasibility of the *** experimental results achieve excellent performance and demonstrate that our method can achieve 94%accuracy.

关键词： Web security visual feature perceptual hash visual similarity

Numerical Investigation on the Aerodynamic Noise generated by a Simplified Double-Strip Pantograph

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Fluid Dynamics & materials Processing 2022年第2期18卷 463-480页

作者： Jiawei Shi Shuai ge Xiaozhen Sheng State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu610031China School of Urban Railway Transportation Shanghai University of Engineering ScienceShanghai201620China

In order to understand the mechanism by which a pantograph can generate aerodynamic noise and grasp its farfield characteristics,a simplified double-strip pantograph is analyzed ***,the unsteady flow field around the pantograph is simulated in the frame of a large eddy simulation(LES)*** the location of the main noise source is determined using surface fluctuating pressure data and the vortex structures in the pantograph flow field are analyzed by means of the *** on this,the relationship between the wake vortex and the intensity of the aerodynamic sound source on the pantograph surface is ***,the far-field aerodynamic noise is calculated by means of the Ffowcs Williams-Hawkings(FW-H)equation,and the contribution of each component to total noise and the frequency spectrum characteristics are *** results show that on the pantograph surface where vortex shedding or interaction with the wake of upstream components occurs,the pressure fluctuation is more intense,resulting in strong dipole *** far-field aerodynamic noise energy of the pantograph is mainly concentrated in the frequency band below 1500 *** peaks in the frequency spectrum are mainly generated by the base frame,balance arm and the rear strip,which are also the main contributors to the aerodynamic noise.

关键词： Pantograph aerodynamic noise vortex structures noise source FW-H equation

A weighted network evolving model with capacity constraints

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Science China(Physics,mechanics & Astronomy) 2013年第9期56卷 1619-1626页

作者： WU XiaoHuan ZHU JinFu WU WeiWei ge Wei College of Civil Aviation Nanjing University of Aeronautics and Astronautics Guangxi Airport Group

most of existing works on complex network assumed that the nodes and edges were uncapacitated during the evolving process,and displayed "rich club" *** we will show that the "rich club" could be changed to "common rich" if we consider the node *** this paper,we define the node and edge attractive index with node capacity,and propose a new evolving model on the base of BBV model,with evolving simulations of the *** the new model,an entering node is linked with an existing node according to the preferential attachment mechanism defined with the attractive index of the existing *** give the theoretical approximation and simulation *** node capacity is finite,the rich node may not be richer further when the node strength approaches or gets to the node *** is confirmed by analyzing the passenger traffic and routes of Chinese main *** to node strength being function of time t,we can use the theoretical approximation solution to forecast how node strength changes and the time when node strength reaches its maximum value.

关键词： complex network evolving weighted network capacity constraints simulation