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Effects of MgO and TiO_2 on the viscous behaviors and phase compositions of titanium-bearing slag

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 868-880页

作者： cong Feng Man-sheng Chu Jue Tang Jin Qin Feng Li Zheng-gen Liu School of Metallurgy Northeastern University

The effects of MgO and TiO_2 on the viscosity, activation energy for viscous flow, and break-point temperature of titanium-bearing slag were studied. The correlation between viscosity and slag structure was analyzed by Fourier transform infrared（FTIR） spectroscopy. Subsequently, main phases in the slag and their content changes were investigated by X-ray diffraction and Factsage 6.4 software package. The results show that the viscosity decreases when the MgO content increases from 10.00wt% to 14.00wt%. Moreover, the break-point temperature increases, and the activation energy for viscous flow initially increases and subsequently decreases. In addition, with increasing TiO_2 content from 5.00wt% to 9.00wt%, the viscosity decreases, and the break-point temperature and activation energy for viscous flow initially decrease and subsequently increase. FTIR analyses reveal that the polymerization degree of complex viscous units in titanium-bearing slag decreases with increasing MgO and TiO_2 contents. The mechanism of viscosity variation was elucidated. The basic phase in experimental slags is melilite. Besides, as the MgO content increases, the amount of magnesia–alumina spinel in the slag increases. Similarly, the sum of pyroxene and perovskite phases in the slag increases with increasing TiO_2 content.

关键词： ironmaking blast furnace slag viscous properties phase composition magnesium oxide titanium dioxide

Intelligent overheating fault diagnosis for overhead transmission line using semantic segmentation

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High Voltage 2024年第2期9卷 309-318页

作者： Xiangyu Yang Youping Tu Zhikang Yuan Zhong Zheng Geng Chen cong Wang Yan Xu Beijing Key Laboratory of High Voltage and EMC North China Electric Power UniversityBeijingChina College of Electronic and Information Engineering Tongji UniversityShanghaiChina

The strain clamps and leading wires are important components that connect conductors on overhead transmission lines and conduct *** operation,poor contact between these components can cause abnormal overheating,leading to electric failures and threatening power system ***,the use of unmanned aerial vehicles equipped with infrared thermal imagers for strain clamp and leading wire maintenance has become increasingly *** learning-based image recognition shows promising prospects for intelligent fault diagnosis of overheating faults.A pre-treatment method is proposed based on dynamic histogram equalisation to enhance the contrast of infrared *** DeepLab v3+network,loss function,and existing networks with different backbones are *** DeepLab v3+network with ResNet101 and convolutional block attention module added,and the Focal Loss function achieved the highest performance with an average pixel accuracy of 0.614,an average intersection over union(AIoU)of 0.567,an F1 score of 0.644,and a frequency weighted intersection over union of 0.594 on the test *** optimised Atrous rates has increased the AIoU by 12.91%.Moreover,an intelligent diagnosis scheme for evaluating the defect state of the strain clamps and leading wires is proposed and which achieves a diagnostic accuracy of 91.0%.

关键词： union fault diagnosis

基于霍夫圆检测的五轴光纤准直器自动耦合装置

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激光技术 2025年第1期49卷 121-127页

作者：郜玉鑫王鹏峰金骥张娜金杰章聪李运堂中国计量大学机电工程学院杭州310018 中国计量大学现代科技学院金华322002

为了解决波分复用器生产过程中光纤准直器耦合装配耗时长、自动化程度低等问题,设计了基于霍夫圆检测的五轴光纤准直器自动耦合装置。利用具有X、Y、Z 3个移动自由度和R、J 2个转动自由度的五轴调节平台带动U型真空吸嘴实现准直器稳定... 详细信息

为了解决波分复用器生产过程中光纤准直器耦合装配耗时长、自动化程度低等问题,设计了基于霍夫圆检测的五轴光纤准直器自动耦合装置。利用具有X、Y、Z 3个移动自由度和R、J 2个转动自由度的五轴调节平台带动U型真空吸嘴实现准直器稳定吸取和位姿调整;采用半透式红外光卡和相机模组构成视觉系统,利用霍夫圆检测获取光卡上光斑的中心坐标,通过五轴调节平台将准直器移动至与光斑中心相同的轴线上实现准直器位姿粗调;采用光功率计测量耦合光功率,由R、J自由度微调准直器获取最佳耦合位姿,实现准直器精准耦合。结果表明,自动耦合装置效率比人工提高6倍,光纤准直器耦合效率高于75%,满足产品质量要求。该研究为光纤准直器高效自动耦合提供了参考。

关键词：光通信光纤准直器霍夫圆检测五轴调节平台真空吸嘴光耦合

基于改进YOLOv8的汽车门板紧固件检测算法

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计算机工程与设计 2025年第1期46卷 298-306页

作者：王晓辉贾韫硕郭丰娟华北电力大学控制与计算机工程学院河北保定071003

针对汽车门板紧固件在复杂场景下存在的检测准确度较低和实时性较差的问题,提出一种小目标改进算法YOLOv8-SOD(small object detection)。在主干网络引入SPD(space-to-depth)模块和自适应权重分配模块,在算法的颈部网络输出位置增加选... 详细信息

针对汽车门板紧固件在复杂场景下存在的检测准确度较低和实时性较差的问题,提出一种小目标改进算法YOLOv8-SOD(small object detection)。在主干网络引入SPD(space-to-depth)模块和自适应权重分配模块,在算法的颈部网络输出位置增加选择性注意力模块,将CIOU损失函数替换为MPDIOU损失函数。实验结果表明,YOLOv8-SOD算法平均检测精度为99.1%,比模板匹配方法和YOLOv8算法分别提高了9.4%、2%,达到了工厂生产流水线的检测标准,具有实用价值。

关键词：汽车门板紧固件检测小目标自适应权重分配无参注意力选择性注意力损失函数深度学习

CASCADIC MULTIGRID METHOD FOR THE MORTAR ELEMENT METHOD FOR P1 NONCONFORMING ELEMENT

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Journal of Computational Mathematics 2005年第4期23卷 425-440页

作者： Chun-jia Bi Dan-hui Hong Department of Mathematics Yantai University Shandong 264005 China Institute of Mathematics Fudan University Shanghai 200433 China

In this paper, we consider the cascadic multigrid method for the mortar P1 nonconforming element which is used to solve the Poisson equation and prove that the cascadic conjugate gradient method is accurate with optim... 详细信息

关键词： Mortar P1 nonconforming element Cascadic multigrid method

Synthesis of novel chiral stationary phases for high-performance liquid chromatography

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Chinese Chemical Letters 2007年第4期18卷 461-464页

作者： Xu Lin Tan Shi cong Hou Qing Hua Bian Min Wang College of Science China Agricultural University Beijing 100094 China

Three novel chiral selectors 4a-c were synthesized from （S）-amino acids and （R）-1-phenyl-2-（4-methylphenyl）ethylamine. 4a-c were connected to 3-aminopropylsilanized silica gel to be used as the chiral stationary phase for HPLC. Five amino acid derivatives and two pyrethroid insecticides were fairly resolved on these three new chiral stationary phases under normal phase condition.

关键词： Enantioseparation Chiral stationary phase Amino acid derivatives Pyrethroid insecticides

Estimation-Correction Modeling and Chaos Control of Fractional- Order Memristor Load Buck-Boost Converter

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Complex System Modeling and Simulation 2024年第1期4卷 67-81页

作者： Lin Wang cong Wang Hongli Zhang Ping Ma Shaohua Zhang School of Electrical Engineering Xinjiang UniversityUrumqi 830017China

A fractional-order memristor load Buck-Boost converter causes periodic system oscillation,electromagnetic noise,and other phenomena due to the frequent switching of the switch in actual operation,which is detrimental to the stable operation of the power electronic *** is of great significance to the study of the modeling method and chaos control strategy to suppress the nonlinear behavior of the Buck-Boost converter and expand the safe and stable operation range of the power *** estimation-correction modeling method based on a fractional active voltage-controlled memristor load peak current Buck-Boost converter is *** discrete numerical solution of the state variables in the continuous mode of the inductor current is *** bursting oscillation phenomenon when the system introduces external excitation is *** bifurcation,Lyapunov exponent,and phase diagrams,a large number of numerical simulations are *** results show that the Buck-Boost converter is chaotic for certain selected parameters,which is the prerequisite for the introduction of the *** on the idea of parameter perturbation and state association,a three-dimensional hybrid control strategy for a fractional memristor Buck-Boost converter is *** effectiveness of the control strategy is verified by simulations,and it is confirmed that the system is controlled in a stable periodic state when the external tunable parameter s,which represents the coupling strength between the state variables in the system,gradually decreases in[-0.4,0].Compared with integer-order controlled systems,the stable operating range of fractional-order controlled systems is much larger.

关键词： fractional-order memristor Buck-Boost converter estimation-correction algorithm hybrid control strategy bursting oscillation

Space-surface bistatic synthetic aperture radar with navigation satellite transmissions: a review

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Science China(Information Sciences) 2015年第6期58卷 5-24页

作者： ANTONIOU Michail CHERNIAKOV Mikhail MA hui Electronic Electrical and Systems Engineering Department University of Birmingham School of Electronic and Information Engineering Beihang University

This paper reviews the theory and practice of Space-Surface Bistatic Synthetic Aperture Radar(SS-BSAR) using navigation satellites as transmitters. In recent years, this innovative technology has reached a maturity stage which allows it to be considered for a wide range of applications. The paper covers the fundamental aspects of this technology as a radar system, such as the resolution, power budget and Point Spread Function(PSF) analysis, as well as its signal processing aspects and the state of the art in terms of advanced SAR techniques that it enables. Finally, the theoretical aspects of the paper may be directly transferred to the more generic SS-BSAR concept.

关键词： bistatic synthetic aperture radar GNSS-based SAR space-surface bistatic SAR coherent change detection multi-perspective imaging

Influence of nanoparticle concentrations on flow boiling heat transfer coefficients of Al_2O_3/R141b in micro heat exchanger by direct metal laser sintering

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1714-1726页

作者： Jianyang Zhou Xiaoping Luo cong Deng Mingyu Xie Lin Zhang Di Wu Feng Guo School of Mechanical and Automobile Engineering South China University of Technology School of Mechanical and Marine Engineering Qinzhou University

Al2O3/R141b ＋ Span-80 nanorefrigerant for 0.05 wt.% to 0.4 wt.% is prepared by ultrasonic vibration to investigate the influence of nanoparticle concentrations on flow boiling heat transfer of Al2O3/R141b ＋ Span-80 in micro heat exchanger by direct metal laser sintering. Experimental results show that nanoparticle concentrations have significantly impact on heat transfer coefficients by homogeneity test of variances according to mathematical statistics. The heat transfer performance of Al2O3/R141b ＋ Span-80 nanorefrigerant is enhanced after adding nanoparticles in the pure refrigerant R141b. The heat transfer coefficients of 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.% Al2O3/R141 b ＋ Span-80 nanorefrigerant respectively increase by 55.0% 72.0%, 53.0% 42.3% and 39.9% compared with the pure refrigerant R141b. The particle fluxes from viscosity gradient, non-uniform shear rate and Brownian motion cause particles to migrate in fluid especially in the process of flow boiling. This migration motion enhances heat transfer between nanoparticles and fluid. Therefore, the heat transfer performance of nanofluid is enhanced. It is important to note that the heat transfer coefficients nonlinearly increase with nanoparticle concentrations increasing. The heat transfer coefficients reach its maximum value at the mass concentration of 0.1% and then it decreases slightly. There exists an optimal mass concentration corresponding to the best heat transfer enhancement. The reason for the above phenomenon is attributed to nanoparticles deposition on the minichannel wall by Scanning Electron Microscopy observation. The channel surface wettability increases during the flow boiling experiment in the mass concentration range from 0.2 wt.% to 0.4 wt.%. The channel surface with wettability increasing needs more energy to produce a bubble. Therefore, the heat transfer coefficients decrease with nanopartide concentrations in the range from 0.2 wt.% to 0.4 wt.%. In addition, a new corre

关键词： Nanoparticle Concentration Minichannel Sintering Flow boiling Heat transfer coefficient