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基于Zernike矩的亚像素边缘定位算法

光学技术 2005年第5期31卷 779-782,785页

作者：崔继文谭久彬哈尔滨工业大学超精密光电仪器工程研究所哈尔滨150001

亚像素软件处理技术可以在一定程度上补偿图像测量系统由硬件限制引起的边缘定位精度,提出了一种基于Zernike矩的亚像素边缘定位算法。该算法利用Zernike多项式的正交性与完备性以及复数矩幅度的旋转不变性计算出边缘的亚像素位置。计... 详细信息

亚像素软件处理技术可以在一定程度上补偿图像测量系统由硬件限制引起的边缘定位精度,提出了一种基于Zernike矩的亚像素边缘定位算法。该算法利用Zernike多项式的正交性与完备性以及复数矩幅度的旋转不变性计算出边缘的亚像素位置。计算出了像素为正方形与矩形(长宽比为4∶3)时的矩模板,使其应用范围进一步扩大。分析了由于矩模板产生的原理偏差,并提出了修正公式,使定位精度得到提高。进一步推导出了实际边缘模型的定位公式,导出了其存在的偏差,并进行了补偿。最终的实验结果表明,补偿后的算法对直线的定位精度达0.05像素,对曲线的定位精度可达0.07像素。

关键词：图像分辨率亚像素定位 Zernike矩模板边缘模型

基于约束抽样H ough变换的圆轮廓快速检测技术

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哈尔滨工业大学学报 2005年第10期37卷 1394-1396,1439页

作者：崔继文谭久彬哈尔滨工业大学超精密光电仪器工程研究所黑龙江哈尔滨150001

针对Hough变换进行圆轮廓测量存在的问题,提出了一种新的Hough变换圆轮廓检测方法.该方法综合利用图像本身灰度信息和梯度信息,对图像空间的抽样进行约束与优化,减小参数的累加数目,得出图像空间中属于目标的轮廓点;并根据目标本身的性... 详细信息

针对Hough变换进行圆轮廓测量存在的问题,提出了一种新的Hough变换圆轮廓检测方法.该方法综合利用图像本身灰度信息和梯度信息,对图像空间的抽样进行约束与优化,减小参数的累加数目,得出图像空间中属于目标的轮廓点;并根据目标本身的性质进一步搜索,去除伪轮廓点;采用了“多对一”映射与并行算法来提高检测速度.实验结果证明应用本方法对于对比度低、有噪声污染的图像同样可以检测出真实轮廓,定位不确定度<0.15像素,运算速度是传统随机Hough变换的2倍.

关键词： Hough变换抽样约束伪轮廓点并行算法

基于变窗口浮动阈值的调制结构光三维测量方法

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计量学报 2008年第B9期29卷 88-92页

作者：崔继文谭久彬哈尔滨工业大学超精密光电仪器工程研究所黑龙江哈尔滨150001

为了解决结构光三维测量中深度信息的准确提取问题，提出了基于变窗口浮动阈值的调制结构光三维测量方法。该方法根据调制结构光相位信息得到被测物体的深度信息，分析条纹图像灰度输出信息与条纹轮廓之间的关系，对每一像素点灰度值在... 详细信息

为了解决结构光三维测量中深度信息的准确提取问题，提出了基于变窗口浮动阈值的调制结构光三维测量方法。该方法根据调制结构光相位信息得到被测物体的深度信息，分析条纹图像灰度输出信息与条纹轮廓之间的关系，对每一像素点灰度值在选定窗口内建立周期函数，并对其在整个图像域内进行周期延拓，利用窗口内灰度的极值构造新的权函数，并以此权函数为依据对不同点分配权值，使窗口内各点灰度满足单调性，从而得到不同的选定阈值。实验结果表明，应用这种变窗口浮动阈值法可以得到很好的分割效果，用于沟槽槽深调制结构光三维测量时，标定后其测量结果的重复性优于0．4μm。

关键词：计量学三维测量调制结构光变窗口浮动阈值周期延拓

Lead-free perovskite Cs_(2)AgBiBr_(6)photodetector detecting NIR light driven by titanium nitride plasmonic hot holes

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Photonics Research 2024年第3期12卷 522-533页

作者： ZIjiAN LIU YUYING XI wenBO ZENG TING ji wenYAN WANG SITONG GUO LINLIN SHI RONG wen YANXIA cui GUOHUI LI College of Physics College of Electronic Information and Optical EngineeringKey Laboratory of Advanced Transducers and Intelligent Control System of Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030032China

Lead-free perovskite Cs_(2)AgBiBr_(6)manifests great potential in developing high-performance,environmentally friendly,solution-processable photodetectors(PDs).However,due to the relatively large energy bandgap,the spectrum responses of Cs_(2)AgBiBr_(6)PDs are limited to the ultraviolet and visible region with wavelengths shorter than 560 *** this work,a broadband Cs_(2)AgBiBr_(6)PD covering the ultraviolet,visible,and near infrared(NIR)range is demonstrated by incorporating titanium nitride(TiN)nanoparticles that are prepared with the assistance of self-assembled polystyrene sphere *** addition,an atomically thick Al2O3layer is introduced at the interface between the Cs_(2)AgBiBr_(6)film and TiN nanoparticles to alleviate the dark current deterioration caused by nanoparticle *** a result,beyond the spectrum range where Cs_(2)AgBiBr_(6)absorbs light,the external quantum efficiency(EQE)of the TiN nanoparticle incorporated Cs_(2)AgBiBr_(6)PD is enhanced significantly compared with that of the control,displaying enhancement factors as high as 2000 over a broadband NIR wavelength *** demonstrated enhancement in EQE arises from the photocurrent contribution of plasmonic hot holes injected from TiN nanoparticles into Cs_(2)AgBiBr_(6).This work promotes the development of broadband solution-processable perovskite PDs,providing a promising strategy for realizing photodetection in the NIR region.

关键词： perovskite titanium ultraviolet

Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei LIANG Shuhui wen Lixin LI jingjing cui School of Electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of Electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-Generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing Binary offloading Cognitive radio Hybrid offloading Resource management

Ketogenic diet therapy in children with epilepsy caused by SLC2A1 mutations:a single-center single-arm retrospective study

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World Journal of Pediatrics 2024年第5期20卷 517-524页

作者： Ying-Yan Wang Yun-Qing Zhou Li-Juan Luo cui-jin Wang Nan Shen Hao Li ji-wen Wang Department of Neurology Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Department of Infectious Diseases Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina Clinical Research Ward Clinical Research CenterShanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Background This retrospective study assessed the efficacy and safety of ketogenic diet therapies in children with epilepsy caused by SLC2A1 genetic mutations and glucose transporter type 1 deficiency *** Pediatric patients with epilepsy symptoms admitted to our medical center between January 2017 and October 2021 were included if they presented with an SLC2A1 genetic mutation on whole-exome *** analyzed the patients’convulsions and treatment with antiepileptic *** patients were followed up at different time periods after ketogenic diet *** Six patients with SLC2A1 mutations were included in this *** patients had seizures of different types and frequencies,and they took antiepileptic drugs to relieve their *** were then treated with a ketogenic diet for at least four *** analyzed epilepsy control rates at 1,2,3,6,and 12 months after ketogenic diet *** patients were seizure-free within a month of receiving the diet *** patients were followed up for six months,three were followed up for 12 months after the treatment,and there was no recurrence of epilepsy during this *** antiepileptic drug withdrawal,none of the patients experienced seizure relapse when receiving ketogenic diet treatment *** severe adverse events occurred during the *** Ketogenic diet therapy is very effective and safe for the treatment of epilepsy caused by SLC2A1 ***,patients with glucose transporter type 1 deficiency syndrome caused by SLC2A1 mutations should begin ketogenic diet treatment as soon as possible.

关键词： Epilepsy Glucose transporter type 1 Ketogenic diet SLC2A1

Finite Element Method for Transient Electric Field by Using Indirect Laplace Transform with High Accuracy

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 401-411页

作者： Teng wen Xiang cui Xuebao Li Sijia Liu Zhibin Zhao State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China China Electric Power Planning&Engineering Institute Beijing 100120China

This paper focuses on the finite element method in the complex frequency domain(CFD-FEM)for the transient electric ***,the initial value and boundary value problem of the transient electric field under the electroquasistatic field in the complex frequency domain is *** addition,the finite element equation and the constrained electric field equation on the boundary are ***,the indirect algorithm of the numerical inverse Laplace transform is *** on it,the calculation procedures of the CFD-FEM are illustrated in ***,the step response,zero-state response under the positive periodic square waveform(PPSW)voltage,and the zero-input response by the CFD-FEM with direct algorithm and indirect algorithm are ***,the reason for the numerical oscillations of the zero-state response under the PPSW voltage is analyzed,and the method to reduce oscillations is *** results show that the numerical accuracy of the indirect algorithm of the CFD-FEM is more than an order of magnitude higher than that of the direct algorithm when calculating the step response of the transient electric *** proposed method can significantly reduce the numerical oscillations of the zero-state response under the PPSW *** proposed method is helpful for the calculation of the transient electric field,especially in the case of frequency-dependent parameters.

关键词： Electroquasistatic field transient electric field finite element method complex frequency domain numerical Laplace transform

Investigating effect of coke porosity on blast furnace performance based on multi-physical fields

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Journal of Iron and Steel Research International 2024年第2期31卷 357-367页

作者： ji Chen Zhao Lei Zhe Yao Li Wang Qiang Ling Ping cui Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan243002AnhuiChina Shanxi Academy of Printing Technology Research Institute Co. Ltd.Xi’an710077ShaanxiChina

Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)***,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions *** makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic ***,the proposed model was validated with the production *** coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were *** results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,***,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive *** the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.

关键词： Blast furnace Mathematical model Multi-physical field Simulation Coke porosity

A novel method for modeling the phase change of iron ore particles in the cohesive zone of a blast furnace

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Particuology 2024年第3期86卷 252-261页

作者： Dianyu E Yingming wen jiayun Dan Youyuan jiang Guangchao Wei jiaxin cui jiangxi Provincial Key Laboratory for Simulation and Modelling of Particulate Systems Jiangxi University of Science and TechnologyNanchang330013China International Institute for Innovation Jiangxi University of Science and TechnologyNanchang330013China Ironmaking Plant Xiangtan Iron and Steel Corporation of Hunan HualingXiangtan411101China Schoolof Transportation and Vehicle Enginering Shandong University of TechnologyZibo255000China

Cohesive zone plays a vital role in the stable operation of a blast furnace(BF),yet the complex phase change process of iron ore particles in this zone is still not well *** this study,a novel one-dimensional(1D)unsteady phase change model was developed to elucidate the heat transfer and melting mechanisms of iron ore *** model validation,the effects of several key operating parameters(e.g.,particle diameter,gas velocity,initial temperature)on the phase change behavior of iron ore particles were analyzed,and the joint effect of multiple parameters was *** results show that larger-sized iron ore particles possess lower specific surface areas,which in turn reduces their convective heat absorption ***,the distance from the solid-liquid phase interface to the particle surface increases,thereby slowing down the movement of the phase interface and pro-longing the melting duration of the *** the gas velocity and the initial temperature does not have a significant impact on reducing the duration of the complete melting *** the specified conditions,it is observed that increasing the gas velocity by 3-fold and 9-fold results in a reduction of the melting duration by 2.4%and 8.3%,*** the initial temperature of iron ore particles results in a decrease in the core-to-surface temperature difference,a slower heating rate,and a shorter duration to achieve *** the factors affecting the melting process,the particle diameter is found to be the most significant in terms of the liquid phase precipitation,mushy zone thickness,and core-to-surface temperature difference of iron ore particles.

关键词： Blast furnace Iron ore melting Cohesive zone Heat transfer Phase change