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低空轻量级红外弱小目标检测算法

激光与红外 2024年第1期54卷 122-129页

作者：张上黄俊锋王恒涛陈永麟王康三峡大学湖北省建筑质量检测装备工程技术研究中心湖北宜昌443002 三峡大学计算机与信息学院湖北宜昌443002

精准的红外弱小目标检测是实时监控、追踪、制导的关键;红外弱小目标存在检测难度高、误检高、漏检严重的问题。为了提高红外弱小目标检测算法的实时性和检测精度,提出了一种超轻量红外弱小目标检测算法SL-YOLO。首先,重设计下采样方案... 详细信息

精准的红外弱小目标检测是实时监控、追踪、制导的关键;红外弱小目标存在检测难度高、误检高、漏检严重的问题。为了提高红外弱小目标检测算法的实时性和检测精度,提出了一种超轻量红外弱小目标检测算法SL-YOLO。首先,重设计下采样方案,针对红外图像特征信息调节网络架构,解决红外弱小目标特征梯度降低和特征消失问题;然后设计网络模型剪枝算法,实现剪枝算法与网络结构的融合,去除冗余参数,实现检测速度的提高;最后设计Varifocal-SIoU损失函数,在均衡正负样本与重叠损失的同时,对正样本进行加权处理,解决背景干扰问题。实验结果表明,在SIRST和IDSAT数据集下检测精度分别提高至96.4%、98.1%,模型体积和计算量可压缩至190 kB、0.9 GFLOPs,推理速度降至3 ms以下。与主流算法进行对比,改进后算法在检测精度、模型体积、计算量等方面均取得了不错的成绩。能够满足实时性检测需求。

关键词：目标检测模型剪枝 YOLOv5 SIoU Varifocal loss

Palladium-Catalyzed Oxidative Alkynylation of Allenyl Ketones: Access to 3-Alkynyl Poly-substituted Furans

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Chinese Journal of Chemistry 2023年第24期41卷 3598-3604页

作者： Bowen Dou kang wang Jianbo wang Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of ChemistryPeking UniversityBeijing100871 China The State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences354 Fenglin LuShanghai200032 China

Furans bearing alkynyl substituents are highly useful in organic ***,the methodologies to access these important furan derivatives are rather *** herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal *** novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional ***,the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the *** reaction reported in this paper further demonstrates the generality of the carbene-based cross coupling.

关键词： Allenyl ketones Oxidative alkynylation Cyclization Isomerization Furans Catalysis Palladium Cross-coupling

Precipitation of α-Fe from Fe_(84-x)Si_(4)B_(12+x)(x=1,3) Amorphous Alloys Under High Magnetic Field Annealing

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Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1163-1172页

作者： Leipeng Duan kang wang Engang wang Peng Jia Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

This work aims to investigate the effects of high magnetic field annealing(HMFA) on the precipitation of α-Fe from Fe_(84-x)Si_(4)B_(12+ x)( x = 1, 3) amorphous precursors. Isothermal annealing process for Fe_(81)Si_(4)B_(15) and Fe_(83)Si_(4)B_(13) amorphous ribbons has been performed with and without the magnetic field. The magnetic field shows the effects of increasing the nucleation rate and decreasing the grain size of α-Fe crystals simultaneously, during the crystallization processes of the investigated amorphous alloys. By applying HMF, α-Fe crystals with more homogeneous distribution and smaller grain size are achieved in the amorphous matrix, which is crucial helpful to improve the magnetic properties for Fe–Si–B amorphous alloys. The mechanism of HMFA affecting the crystallization microstructure is also discussed in the present work.

关键词： High magnetic field Crystallization α-Fe Nucleation Grain size Atomic diffusion

“Relay-mode”promoting permeation of water-based fire extinguishing agent in granular materials porous media stacks

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Chinese Journal of Chemical Engineering 2022年第7期35卷 98-112页

作者： kang wang Wei Tan Liyan Liu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300350China

Water-based fire extinguishing agent is the main means to deal with smoldering ***,due to the hydrophobic properties of the particle surface,the porous medium channel provide resistance and slow down the extinguishing agent flow during the downward permeation *** promote the liquid permeation process in such porous media,this work studied liquid imbibition process and analyzed the oscillating and attenuating process of liquid level in capillary channel by theoretical,experimental,and numerical *** empirical mathematical equation was proposed to describe the oscillating process,and the effects of the capillary diameter and contact angle parameters on the transportation process were *** on this,the“relay-mode”was proposed to promote the liquid transportation ***,the transient simulation results of liquid permeation in coal stacks showed when the liquid flowed through the channel with changed diameter from large to small ones,the transportation distance was several times longer than that through the unidiameter *** trend of liquid“relay-mode”in capillaries can be used to promote the permeation in granular materials porous media *** relevant results also provide new thoughts to develop the water-based fire extinguishing agents and then improve the firefighting efficiency of deep-seated fire in porous media stacks.

关键词： Granular materials Porous media Safety Permeation Water-based fire extinguishing agent

科教兴省、人才强省背景下河南全方位育才、引才、用才的路径与对策研究

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焦作大学学报 2024年第2期38卷 45-48,52页

作者：王慧王康李海涛焦作大学人文学院河南焦作454000 焦作大学人事处河南焦作454000

当今世界展开的全方位竞争本质上是人才的竞争,谁拥有的人才数量更多并能发挥他们的最大潜力,谁就能赢得竞争。河南未来要想在国内科技、经济、文化领域扮演更重要的角色,就必须加快推动产业结构的战略性调整,推进“四个强省”建设,而... 详细信息

当今世界展开的全方位竞争本质上是人才的竞争,谁拥有的人才数量更多并能发挥他们的最大潜力,谁就能赢得竞争。河南未来要想在国内科技、经济、文化领域扮演更重要的角色,就必须加快推动产业结构的战略性调整,推进“四个强省”建设,而这些目标的实现,离不开人才的支持和推动。梳理并分析了河南人才资源现状及其问题,提出了全方位育才、引才、用才的路径与对策,对河南未来人才队伍建设提供有益参考。

关键词：河南人才资源人才队伍建设

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基于柱形容器缠绕特性的控制稳定性分析

河北科技大学学报 2024年第1期45卷 26-34页

作者：王康路永婕郭子腾王加富张海东王君哲陈丰雨中国兵器工业集团山东北方现代化学工业有限公司山东济南250031 省部共建交通工程结构力学行为与系统安全国家重点实验室河北石家庄050043 河北科技大学机械工程学院河北石家庄050018

针对玻璃纤维缠绕机在工作中由于张力不稳定导致的线型变化,以及在高速缠绕模式下的张力调节不稳定的问题,设计了自适应模糊PID控制策略以及适用于高速缠绕工况的滑模控制策略。首先,针对缠绕工况建立缠绕动力学模型、张力控制模型;其次... 详细信息

针对玻璃纤维缠绕机在工作中由于张力不稳定导致的线型变化,以及在高速缠绕模式下的张力调节不稳定的问题,设计了自适应模糊PID控制策略以及适用于高速缠绕工况的滑模控制策略。首先,针对缠绕工况建立缠绕动力学模型、张力控制模型;其次,引入模糊PID控制策略和滑模控制策略分别对不同工况下的缠绕特性进行MATLAB-Simulink仿真,寻找最优控制策略;最后,基于被验证的最优控制策略进行实验。结果表明,在模糊PID控制的调节下,不同速度变化下的缠绕张力相对于无控制得到较好改善,提高了柱形容器在缠绕时的线性稳定性和张力稳定性。模糊PID控制对缠绕时的张力调节精度优于滑模控制,为大型管道缠绕设备提供了新的研究思路。

关键词：自动控制理论纤维缠绕 MATLAB-Simulink仿真模糊PID控制滑模控制硬件实验

Directing group-assisted transition-metal-catalyzed vinylic C–H bond functionalization

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Science China Chemistry 2015年第8期58卷 1252-1265页

作者： kang wang Fangdong Hu Yan Zhang Jianbo wang Beijing National Laboratory of Molecular Sciences (BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry Peking University

Transition-metal-catalyzed C–H bond activation represents one of the most attractive research areas in organic *** contrast to the great developments made in directed C–H bond functionalization of arenes,the directing group-assisted activation of non-aromatic vinylic C–H bonds still remains *** the recent years,significant progress has been made in this fascinating field with various functionalized alkenes,heterocycles and carbocycles being *** article will focus on the recent achievements in the field of directing-group-assisted vinylic C–H bond functionalization.

关键词： transition-metal-catalysis organic synthesis C-H bond functionalization vinylic C-H bond

考虑降压节能和光伏误差三维特性的主动配电网多时间尺度优化调度

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电力建设 2024年第8期45卷 159-172页

作者：张光儒马振祺陈杰张家午王康冯天橼王成福国网甘肃省电力公司电力科学研究院兰州市730070 山东大学电气工程学院济南市250061

高比例分布式光伏的分散、随机特性加剧了配电系统潮流分布的不确定性,使得配电系统的安全经济运行面临严峻挑战。提出了考虑降压节能调节和分布式光伏预测误差三维特性的主动配电网多时间尺度优化调度方法。首先,分析负荷功率与馈线电... 详细信息

高比例分布式光伏的分散、随机特性加剧了配电系统潮流分布的不确定性,使得配电系统的安全经济运行面临严峻挑战。提出了考虑降压节能调节和分布式光伏预测误差三维特性的主动配电网多时间尺度优化调度方法。首先,分析负荷功率与馈线电压的灵敏度关系,提出了基于降压节能调节方法的综合负荷建模方法。其次,从时间-空间-功率三维角度,建立了一种分布式光伏预测误差的三维分析模型,为调度提供更精准的误差分析结果。然后,基于降压节能方法和预测误差三维分析模型,构建了可有效协调日前慢速调节资源与日内快速响应资源的主动配电网多时间尺度优化调度模型。最后,以改进IEEE 33节点系统为算例进行分析,算例分析结果表明所提误差建模方法对光伏功率有着较好的跟随效果,且基于该模型的优化调度策略能够减少误差随机性对调度决策的影响,提升配电系统运行的安全性与经济性。

关键词：主动配电网优化调度分布式光伏预测误差建模降压节能技术多时间尺度

Variable Selection for Varying Coefficient Models Via Kernel Based Regularized Rank Regression

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Acta Mathematicae Applicatae Sinica 2020年第2期36卷 458-470页

作者： kang-ning wang Lu LIN School of Statistics Shandong Technology and Business UniversityYantai 264005China Institute for Financial Studies Shandong UniversityJinan 250100China

A robust and efficient shrinkage-type variable selection procedure for varying coefficient models is proposed,selection consistency and oracle properties are ***,a BIC-type criterion is suggested for shrinkage parameter selection and theoretical property is *** studies and real data analysis also are included to illustrate the finite sample performance of our method.

关键词： rank regression oracle property variable selection asymptotic relative efficiency BIC-type criterion