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Hermite-Shannon-Cosine区间小波及其在图形自适应分划插值中的应用

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计算机辅助设计与图形学学报 2021年第10期33卷 1573-1581页

作者：孟可欣刘梦郭书君梅树立中国农业大学信息与电气工程学院北京100083

动态曲线图是描述客观现象变换规律的常用工具,为实现动态曲线特征点的动态捕捉及精确表达,构造了同时具有插值性、光滑性、紧支撑性和对称性的Shannon-Cosine小波函数.首先利用Shannon小波函数的波动性和连续性,根据积分中值定理,设计... 详细信息

动态曲线图是描述客观现象变换规律的常用工具,为实现动态曲线特征点的动态捕捉及精确表达,构造了同时具有插值性、光滑性、紧支撑性和对称性的Shannon-Cosine小波函数.首先利用Shannon小波函数的波动性和连续性,根据积分中值定理,设计了一种参数化的窗函数,通过参数调整,可满足Shannon-Cosine小波对支撑区间和光滑度的自适应控制的要求;其次,分析确定了对曲线进行小波变换时边界效应归因于曲线边界的不连续,因此,采用2点3次Hermite插值函数构建了区间小波;最后,采用多尺度Shannon-Cosine小波对冲击波传播曲线和反射Burger曲线进行多尺度自适应细分和逼近,自动捕捉曲线的特征点进行重构.实例结果表明,与其他方法相比,Hermite Shannon-Cosine区间小波逼近曲线具有较高的数值精度和较低的算法复杂度.

关键词： Shannon-Cosine小波 Hermite插值光滑曲线

A hybrid attention model based on first-order statistical features for smoke recognition

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Science China(Technological Sciences) 2024年第3期67卷 809-822页

作者： GUO Nan LIU JiaHui DI kexin GU Ke QIAO JunFei Beijing Laboratory of Smart Environmental Protection Beijing Key Laboratory of Computational Intelligence and Intelligent SystemBeijing Artificial Intelligence InstituteBeijing 100124China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

Smoke and fire recognition are of great importance on foreseeing fire disasters and preventing environmental pollution by monitoring the burning process of objects(e.g., straw, fuels). However, since fire images suffer from problems like the variability of the features, complexity of scenarios, interference from background, changeable weather conditions as well as image quality problems, identifying smoke and fire accurately and promptly from a given image still remains a substantial challenge. Automatically learning the features of smoke images by CNNs has improved the target recognition ability compared to traditional approaches,nonetheless, convolutions and pooling operations in CNNs may cause severe information loss which may lead to *** tackle the above problems, this paper proposed a hybrid attention model based on the characteristics of smoke images. This model adopted multiple optimized attention mechanism in several stages to quickly and precisely capture the important features,achieving state-of-the-art performance on smoke and fire recognition in terms of accuracy and speed. Our proposed module mainly consists of two stages: pooling and attention. In the first stage, we conducted several newly proposed first-order pooling methods. Through traversing the data space in a larger scope, features are better reserved, thus constructing a more intact feature space of smoke and fire in an image. In the second stage, feature maps are aggregated together to perform channel and spatial attention. The channel and spatial dependencies allow us to quickly catch the important features presented in an image. By fully exploring the feature space and prominent salient features, characteristics of smoke and fire are better presented so as to obtain better smoke and fire detection results. Experiments have been conducted on public smoke detection dataset and new proposed fine-grained smoke and fire detection database. Experimental results revealed that the propose

关键词： hybrid attention first-order pooling smoke and fire detection deep convolutional neural networks

Bifunctional interstitial phosphorous doping strategy boosts platinum-zinc alloy for efficient ammonia oxidation reaction and hydrogen evolution reaction

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Nano Research 2024年第3期17卷 1182-1189页

作者： Tianqi Yu kexin Tan Jia Wu Yongjin Zou Shibin Yin Guangxi Key Laboratory of Electrochemical Energy Materials School of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Information Materials Guilin University of Electronic TechnologyGuilin 541004China

It is still a lack of bifunctional catalysts for ammonia oxidation reaction(AOR)and hydrogen evolution reaction(HER)due to their different reaction *** this work,P is doped into PtZn alloy by calcination with NaH_(2)PO_(2) as P source to induce the lattice tensile strain of Pt and the electronic interaction between P and Zn,which optimizes the AOR and HER activity *** sample with the optimal P content can drive the AOR peak current density of 293.6 mA·mgPt^(-1),which is almost 2.7 times of *** HER,the overpotential at^(-1)0 mA·cm^(-2) is only 23 mV with Tafel slope of 34.1 mV·dec^(-1).Furthermore,only 0.59 V is needed to obtain 50 mA·mgPt^(-1) for ammonia electrolysis under a two-electrode ***,this work shows an ingenious method to design bifunctional catalysts for ammonia electrolysis.

关键词： PtZn alloy phosphorous doping ammonia oxidation reaction hydrogen evolution reaction bifunctional catalyst

Research progress and future prospects in the service security of key blast furnace equipment

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2121-2135页

作者： Yanxiang Liu kexin Jiao Jianliang Zhang Cui Wang Lei Zhang Xiaoyue Fan School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research Institute of Macro-Safety Science University of Science and Technology BeijingBeijing 100083China

The safety and longevity of key blast furnace(BF)equipment determine the stable and low-carbon production of *** pa-per presents an analysis of the heat transfer characteristics of these components and the uneven distribution of cooling water in parallel pipes based on hydrodynamic principles,discusses the feasible methods for the improvement of BF cooling intensity,and reviews the pre-paration process,performance,and damage characteristics of three key equipment pieces:coolers,tuyeres,and hearth ***-thermoere,to attain better control of these critical components under high-temperature working conditions,we propose the application of optimized technologies,such as BF operation and maintenance technology,self-repair technology,and full-lifecycle management ***,we propose further researches on safety assessments and predictions for key BF equipment under new operating conditions.

关键词： blast furnace equipment service security blast furnace campaign self-repair

Lagrangian coherent structure analysis on transport of Acetes chinensis along coast of Lianyungang,China

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Journal of Oceanology and Limnology 2024年第1期42卷 345-359页

作者： kexin WANG Xueqing ZHANG Qi LOU Xusheng XIANG Ying XIONG College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Marine Environment and Ecology Ministry of Education of ChinaOcean University of ChinaQingdao 266100China Jiangsu Marine Fisheries Research Institute Nantong 226007China

Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to *** focused on the accumulation and dynamic mechanism of the Acetes chinensis in the Lianyungang nearshore licensed fishing *** Lagrangian frame approaches including the Lagrangian coherent structures theory,Lagrangian residual current,and Lagrangian particle-tracking model were applied to find the transport pathways and aggregation characteristics of Acetes *** exist some material transport pathways for Acetes chinensis passing through the licensed fishing area,and Acetes chinensis is easy to accumulate in the licensed fishing *** main mechanism forming this distribution pattern is the local circulation induced by the nonlinear interaction of topography and tidal *** the Lagrangian coherent structure analysis and the particle trajectory tracking indicate that Acetes chinensis in the licensed fishing area come from the nearshore *** work contributed to the adjustment of licensed fishing area and the efficient utilization of fishery resources.

关键词： plankton accumulation hydrodynamic model Lagrangian particle-tracking model Lagrangian analysis

Epicatechin attenuates lead(Pb)-induced cognitive impairment in mice:regulation on Nrf2 signaling pathway,and interference on the interaction between Pb with albumin

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Food Science and Human Wellness 2024年第2期13卷 1065-1078页

作者： Dai Cheng Qianqian Yu kexin Zhu Dingdong Bu Zijian Wu State Key Laboratory of Food Nutrition and Safety Tianjin University of Science&TechnologyTianjin 300457China School of Biotechnology and Food Science Tianjin University of CommerceTianjin 300134China

Epicatechin(EC)was used in this study to antagonize the cognitive dysfunction caused by lead(Pb)exposure in ***-week-old male Kunming mice were treated with PbCl_(2)(20 mg/kg)and/or EC(50 mg/kg)by gavage administration for 4 *** water maze test showed that EC could improve memory dysfunction induced by *** antagonized Ca^(2+)overload,activated Nrf2 signaling pathway and reduced the accumulation of Pb in the brain and serum,which suggested that EC might alter Pb distribution in *** vitro,spectroscopic analysis,potentiometric titration and docking studies were applied to inquiry into the interaction between bovine serum albumin(BSA)and Pb^(2+)in presence or absence of *** was proved to chelate Pb^(2+)and reduced the interaction between BSA and Pb^(2+).In summary,EC might protect Pb-induced cognitive impairment by activating Nrf2 signaling pathway,and suppressing Pb accumulation via interference on the binding of Pb to albumin.

关键词： Lead Epicatechin Bovine serum albumin Interaction Oxidative stress

单管多翅片排管蒸发器结构优化的数值模拟研究

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冷藏技术 2024年第3期47卷 28-34页

作者：孙志利闫江漫张学锋孟珂欣刘娥玉刘洪宇金蕊李蕾刘浩威王允直马坤茹天津商业大学冷冻冷藏技术教育部工程研究中心农业农村部农产品低碳冷链重点实验室天津市制冷技术重点实验室天津300134 华润物流(沙田冷仓)有限公司中国香港999077 西部机场集团青海机场有限公司青海810007 河北尚恒制冷设备科技有限公司河北054001 河北科技大学石家庄050091

为解决单管双翅片排管蒸发器翅片效率低、降温速率慢和原材料消耗量大的问题,通过模拟分析翅片间夹角对传热性能的影响,得到单管双翅片和四翅片的降温时间、温度场、速度场、传热系数和制冷量指标。结果表明,四翅片排管蒸发器下部翅片... 详细信息

为解决单管双翅片排管蒸发器翅片效率低、降温速率慢和原材料消耗量大的问题,通过模拟分析翅片间夹角对传热性能的影响,得到单管双翅片和四翅片的降温时间、温度场、速度场、传热系数和制冷量指标。结果表明,四翅片排管蒸发器下部翅片夹角越大,传热效果越好。单管四翅片排管蒸发器1的传热系数最大,相对于单管双翅片排管蒸发器提高了13.4%;单管四翅片排管蒸发器1的单位管材制冷量最高,相对与单管双翅片排管蒸发器提高了38.6%。研究为单管多翅片蒸发器结构优化提供了支撑。

关键词：单管多翅片排管蒸发器温度场速度场制冷量

Realization of Quantum Secure Direct Communication with Continuous Variable

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Research 2024年第2期6卷 159-170页

作者： Zhengwen Cao Yuan Lu Geng Chai Hao Yu kexin Liang Lei Wang School of Information Science and Technology Northwest UniversityXi'an710127China

With the progress of theoretical and applied technologies,the communication system based on the classical encryption is seriously threatened by quantum computing and distributed computing.A communication method that directly loads confidential information on the quantum state,quantum secure direct communication(QSDC),came into being for resisting security ***,we report the first continuous-variable QSDC(CV-QSDC)experimental demonstration for verifying the feasibility and effectiveness of the CV-QSDC protocol based on Gaussian mapping and propose a parameter estimation for signal classification under the actual *** our experiment,we provided 4×10^(2) blocks,where each block contains 105 data for direct information *** the transmission distance of 5 km in our experiment,the excess noise is 0.0035 SNU,where SNU represents the unit of shot-noise *** 4.08×10^(5) bit per second experimental results firmly demonstrated the feasibility of CV-QSDC under the fiber *** proposed grading judgment method based on parameter estimation provides a practical and available message processing scheme for CV-QSDC in a practical fiber channel and lays the groundwork for the grading reconciliation.

关键词： quantum estimation verify

The incidence rate and histological characteristics of intimal hyperplasia in elastase-induced experimental abdominal aortic aneurysms in mice

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Animal Models and Experimental Medicine 2024年第3期7卷 388-395页

作者： meng Li Panpan Wei kexin Li Haole Liu Naqash Alam Haiwen Hou Jie Deng Baohui Xu Enqi Liu Sihai Zhao Yankui Li Laboratory Animal Center Xi'an Jiaotong UniversityXi'anChina Department of Vascular Surgery The Second Hospital of Tianjin Medical UniversityTianjinChina Department of Cardiology The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina Department of Vascular Surgery Stanford University School of MedicineStanfordCaliforniaUSA

Intimal hyperplasia(IH)is a negative vascular remodeling after arterial *** occasionally occurs in elastase-induced abdominal aortic aneurysm(AAA)mouse *** study aims to clarify the incidence and histological characteristics of IH in aneurysmal mice.A retrospective study was conducted by including 42 male elastaseinduced mouse AAA *** IH incidence,aortic diameters with or without IH,and hyperplasia lesional features of mice were *** 42 elastase-induced AAA mouse models,10 mice developed mild IH(24%)and severe IH was found in only 2 mice(5%).The outer diameters of the AAA segments in mice with and without IH did not show significant *** mild and severe IH lesions show strong smooth muscle cell positive staining,but endothelial cells were occasionally observed in severe IH *** was obvious macrophage infiltration in the IH lesions of the AAA mouse models,especially in mice with severe ***,only a lower numbers of T cells and B cells were found in the IH *** cell-secreted matrix metalloproteinases(MMP)2 was highly expressed in all IH lesions,but MMP9 was only overexpressed in severe *** conclusion,this study is the first to demonstrate the occurrence of aneurysmal IH and its histological characteristics in an elastaseinduced mouse AAA *** will help researchers better understand this model,and optimize it for use in AAA-related research.

关键词： abdominal aortic aneurysms animal model histology intimal hyperplasia