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E2E-MFERC:AMulti-Face Expression Recognition Model for Group Emotion Assessment
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作者 Lin Wang Juan Zhao +1 位作者 Hu Song Xiaolong Xu 《Computers, Materials & Continua》 SCIE EI 2024年第4期1105-1135,共31页
In smart classrooms, conducting multi-face expression recognition based on existing hardware devices to assessstudents’ group emotions can provide educators with more comprehensive and intuitive classroom effect anal... In smart classrooms, conducting multi-face expression recognition based on existing hardware devices to assessstudents’ group emotions can provide educators with more comprehensive and intuitive classroom effect analysis,thereby continuouslypromotingthe improvementof teaching quality.However,most existingmulti-face expressionrecognition methods adopt a multi-stage approach, with an overall complex process, poor real-time performance,and insufficient generalization ability. In addition, the existing facial expression datasets are mostly single faceimages, which are of low quality and lack specificity, also restricting the development of this research. This paperaims to propose an end-to-end high-performance multi-face expression recognition algorithm model suitable forsmart classrooms, construct a high-quality multi-face expression dataset to support algorithm research, and applythe model to group emotion assessment to expand its application value. To this end, we propose an end-to-endmulti-face expression recognition algorithm model for smart classrooms (E2E-MFERC). In order to provide highqualityand highly targeted data support for model research, we constructed a multi-face expression dataset inreal classrooms (MFED), containing 2,385 images and a total of 18,712 expression labels, collected from smartclassrooms. In constructing E2E-MFERC, by introducing Re-parameterization visual geometry group (RepVGG)block and symmetric positive definite convolution (SPD-Conv) modules to enhance representational capability;combined with the cross stage partial network fusion module optimized by attention mechanism (C2f_Attention),it strengthens the ability to extract key information;adopts asymptotic feature pyramid network (AFPN) featurefusion tailored to classroomscenes and optimizes the head prediction output size;achieves high-performance endto-end multi-face expression detection. Finally, we apply the model to smart classroom group emotion assessmentand provide design references for classroom effect analysis evaluation metrics. Experiments based on MFED showthat the mAP and F1-score of E2E-MFERC on classroom evaluation data reach 83.6% and 0.77, respectively,improving the mAP of same-scale You Only Look Once version 5 (YOLOv5) and You Only Look Once version8 (YOLOv8) by 6.8% and 2.5%, respectively, and the F1-score by 0.06 and 0.04, respectively. E2E-MFERC modelhas obvious advantages in both detection speed and accuracy, which can meet the practical needs of real-timemulti-face expression analysis in classrooms, and serve the application of teaching effect assessment very well. 展开更多
关键词 multi-face expression recognition smart classroom end-to-end detection group emotion assessment
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A Cradle-to-Cradle Novel Approach for Wastewater Management in Sustainable Urban Communities
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作者 Mianda Khattab Salah El Haggar Ahmed El Gendy 《Journal of Environmental Protection》 CAS 2023年第3期163-171,共9页
Water, a valuable resource to human lives, is being abused and driven to scarcity. This scarcity is leading some countries and areas to face difficulty in accessing drinking water. As the UN recently stated “by 2050 ... Water, a valuable resource to human lives, is being abused and driven to scarcity. This scarcity is leading some countries and areas to face difficulty in accessing drinking water. As the UN recently stated “by 2050 water shortages and harder access will be reached by around 2/3<sup>rd</sup> of the world total population” [1], thus, there is a high need to treat and reuse wastewater for domestic purposes, which will lead to less reliance on fresh water as an initial water source. Greywater—defined as the water produced in domestic houses including sinks and bathroom showers, and excluding any blackwater mix which is collected from toilets—is a type of wastewater. Greywater accounts for up to 75% of the daily water produced [2] while it has fewer contaminants when compared to blackwater. This makes greywater a focal point for treatment, and reusing to conserve fresh water and approach net zero water concept. Even though the definition of greywater is the same globally, its criteria can differ from one country to another, from one building to another, or even from the same person’s usage along the day. Accordingly, several treatment methods evolved over years aiming at treating the produced greywater for reuse mainly in irrigation and toilet flushing. The objective of this paper is to demonstrate a novel net zero wastewater approach applying cradle-to-cradle concept for urban communities;while also proposing a sustainable greywater treatment technique that is environmentally friendly, cost-effective and socially acceptable. 展开更多
关键词 Net Zero Water Sustainable Urban Communities cradle to cradle for Wastewater Management Sustainable Greywater Treatment
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TMT三镜缩比系统cradle组件结构设计与分析 被引量:2
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作者 姜海波 赵宏超 杨飞 《长春理工大学学报(自然科学版)》 2017年第4期7-9,13,共4页
三十米望远镜(TMT)三镜系统具有跟踪瞄准功能,其结构类似于地平式望远镜,其镜室托架(cradle)功能相当于望远镜中的四通组件,其结构设计对系统指标有着直接的影响。以三镜缩比系统为例,为了提高cradle组件的结构刚度质量比,根据三镜系统... 三十米望远镜(TMT)三镜系统具有跟踪瞄准功能,其结构类似于地平式望远镜,其镜室托架(cradle)功能相当于望远镜中的四通组件,其结构设计对系统指标有着直接的影响。以三镜缩比系统为例,为了提高cradle组件的结构刚度质量比,根据三镜系统结构特点,提出了桁架拼接式的结构设计,利用有限元方法对其进行了静力分析和模态分析。结果表明,在重力沿x、y、z方向三种工况下,cradle组件最大变形分别为0.064mm、0.015mm、0.025mm,其一阶固有频率为74.4Hz,利用模态分析仪对cradle组件实物进行了模态检测,其结果与模态分析前四阶结果最大相对误差为10.2%,显示所设计结构满足使用需求。 展开更多
关键词 三十米望远镜 缩比系统 镜室托架 桁架 有限元分析
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Multi-face detection based on downsampling and modified subtractive clustering for color images 被引量:10
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作者 KONG Wan-zeng ZHU Shan-an 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第1期72-78,共7页
This paper presents a multi-face detection method for color images. The method is based on the assumption that faces are well separated from the background by skin color detection. These faces can be located by the pr... This paper presents a multi-face detection method for color images. The method is based on the assumption that faces are well separated from the background by skin color detection. These faces can be located by the proposed method which modifies the subtractive clustering. The modified clustering algorithm proposes a new definition of distance for multi-face detection, and its key parameters can be predetermined adaptively by statistical information of face objects in the image. Downsampling is employed to reduce the computation of clustering and speed up the process of the proposed method. The effectiveness of the proposed method is illustrated by three experiments. 展开更多
关键词 multi-face detection Skin color Modified subtractive clustering Downsampling
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Integration of the “Cradle of Oil” and the “Belt and Road” to Forge a Brand Supporting the Chad Project
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作者 Yu Zhuangzai 《China Oil & Gas》 CAS 2018年第6期20-24,共5页
Resplendence of the “cradle of oil”Yumen Oilfield,developed in 1939,is the first natural oil base in China.The current Yumen Oilfield is a regional branch of China National Petroleum Corporation (CNPC).It is a state... Resplendence of the “cradle of oil”Yumen Oilfield,developed in 1939,is the first natural oil base in China.The current Yumen Oilfield is a regional branch of China National Petroleum Corporation (CNPC).It is a state-owned enterprise integrating exploration and development,oil refining and chemical engineering,and engineering technology and mining services.During the war of “a drop of oil,a drop of blood”,oil products produced in oil fields provided practical support for the War of Resistance Against Japan.In the decade before liberation,only 520,000 tons of crude oil were produced in Yumen Oilfield,but it accounted for 95% of crude oil output in China at that time. 展开更多
关键词 INTEGRATION cradle of OIL BELT and ROAD
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Theoretical and Practical Basis for Progressive Multi-face Technology of Mine Development
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《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期22-23,共2页
关键词 Theoretical and Practical Basis for Progressive multi-face Technology of Mine Development
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SEPW-the Cradle of Surge Arresters and Fuses in China
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作者 Wang YongliangShanghai Electric Porcelain Works 《Electricity》 1996年第1期40-43,共4页
Shanghai Electric Porcelain Works (SEPW), a subsidiary enterprise of the SEC (Group), is specialized in manufacturing highvoltage surge arresters and fuses as main products, as well as some high-voltage insulators, wa... Shanghai Electric Porcelain Works (SEPW), a subsidiary enterprise of the SEC (Group), is specialized in manufacturing highvoltage surge arresters and fuses as main products, as well as some high-voltage insulators, wall bushings and disconnecting switches for power transmission & distribution systems. In fact, SEPW is 展开更多
关键词 MOA SEPW-the cradle of Surge Arresters and Fuses in China HIGH SIC
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A Cradle of Artists─—Introducing the Beijing Opera School
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《China & The World Cultural Exchange》 1997年第1期24-25,共2页
关键词 Introducing the Beijing Opera School A cradle of Artists
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Chinese Opera Institute: Cradle of Traditional Theatrical Performers
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《China & The World Cultural Exchange》 1996年第4期20-23,共4页
关键词 Chinese Opera Institute cradle of Traditional Theatrical Performers
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The Golden Cradle
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《China Today》 1998年第1期56-58,共3页
TheGoldenCradleByStaffReporterSUNLINAWhenachildlessthenthreeyearsofagecanreciteancientpoetry,quotepopularidi... TheGoldenCradleByStaffReporterSUNLINAWhenachildlessthenthreeyearsofagecanreciteancientpoetry,quotepopularidioms,andwriteChine... 展开更多
关键词 GOLDEN cradle The
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The Cradle of China’s Drama Talents─A Brief Introduction to the Central Drama Institute in China
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《China & The World Cultural Exchange》 1995年第6期38-39,共2页
关键词 In The cradle of China’s Drama Talents A Brief Introduction to the Central Drama Institute in China
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Changyang,Cradle of the Tujia People
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《China Today》 2002年第12期2-3,共2页
Changyang Tujia Autonomous County in western Hubei Province is an area of mountains and waters, most notably the 400-km Qingjiang River that traverses it from east to west. According to historical documents, Wuluo Zho... Changyang Tujia Autonomous County in western Hubei Province is an area of mountains and waters, most notably the 400-km Qingjiang River that traverses it from east to west. According to historical documents, Wuluo Zhongli Mountain, 30 kilometers southwest of the county seat, is where the Ba people, ancestors of China s Tujia ethnic minority, originated. It is believed that Linjun, the Tujia primogenitor, was born in the mountain s Red Cave. Surrounded by water on three sides, the mountain has five steep peaks, the highest 384 meters above sea level, and is densely covered by verdant forest. A visit to the county is a must for anyone interested in the history of the Ba people. 展开更多
关键词 Changyang cradle of the Tujia People
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The Cradle of Tibetan Cadres
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作者 CEWANGJIGMEI 《China Today》 1998年第9期27-29,共3页
关键词 The cradle of Tibetan Cadres
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Eagles Are Hovering at the Cradle of Love Songs
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作者 Yi Shizhong Bao Lida 《China's Tibet》 2008年第3期69-70,共2页
In the late autumn of 2007,the Southwest Branch of China Airlines sent offone A319 airbus,named B6238,to cross over Mt.Gongkya (7556 meters above sea level) and safely land at the Kangding Airport - which is acknowled... In the late autumn of 2007,the Southwest Branch of China Airlines sent offone A319 airbus,named B6238,to cross over Mt.Gongkya (7556 meters above sea level) and safely land at the Kangding Airport - which is acknowledged as the world's second highest airport.The success of the experimental flight ends the history of unavailabil- ity of civil airline flights in Garze Autonomous Prefecture of Sichuan Province.It also marks the closure of the final preparation phase and readiness to move to the next stage-l... 展开更多
关键词 Eagles Are Hovering at the cradle of Love Songs
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The Cradle of China's First Class Seafarers:Qingdao Ocean Shipping Mariners College——by Lin Jinhe,President of Qingdao Ocean Shipping Mariners College
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《中国远洋航务》 1998年第11期18-19,共2页
Qingdao Ocean Shipping Mariners College is a College subordinate to China Ocean Shipping (Group) Company under the Ministry of Communications. In our college there are the Department of Marine Navigation,Department of... Qingdao Ocean Shipping Mariners College is a College subordinate to China Ocean Shipping (Group) Company under the Ministry of Communications. In our college there are the Department of Marine Navigation,Department of Marine Engineering, Department of Shipping Management and Department of Foreign Languages, offering speciahies of Marine Navigation, Marine Engine Control, Marine Electrical Equipment Control, Marine Radio Communication, International Shipping Management and International Finance and Accounting. We have 3 types of education: the education of formal college schooling, the training for implementation of the 95 revised STCW Convention and the continuation education. Meanwhile we undertake different training of COSCO’s contracted seafarers overseas and other managerial per- 展开更多
关键词 by Lin Jinhe President of Qingdao Ocean Shipping Mariners College The cradle of China’s First Class Seafarers
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区域科技创新策源地:理论发凡、现实基础及政策建议——基于安徽视角
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作者 赵菁奇 《淮南师范学院学报》 2024年第1期60-66,共7页
科技创新策源地是实现高水平科技自立自强的战略支撑。文章系统梳理了科技创新策源地的理论内涵和学理基础,采用实证法分析了安徽打造区域科技创新策源地的现实基础和存在困境。安徽打造科技创新策源地要以合肥综合性国家科学中心、合... 科技创新策源地是实现高水平科技自立自强的战略支撑。文章系统梳理了科技创新策源地的理论内涵和学理基础,采用实证法分析了安徽打造区域科技创新策源地的现实基础和存在困境。安徽打造科技创新策源地要以合肥综合性国家科学中心、合肥国家实验室为策源基石,以大学和科研院所为策源基础,以科技创新企业为策源动力,以创新环境为策源引领。 展开更多
关键词 科技创新 策源地 安徽
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输毛管中流场状态对纤维丝束开松处理效果的影响
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作者 王进 程贺棚 +4 位作者 李帅 卢贺 崔永志 千翠娥 于贺春 《现代纺织技术》 北大核心 2024年第3期29-37,共9页
纤维输毛管的设计对粘胶纤维或Lyocell短纤维丝束的开松效果至关重要。为了探究纤维丝束在输毛管中的开松机理以及管道内流场状态对纤维运动状态的影响,采用三维建模软件建立输毛管流场模型,在商用软件Cradle CFD中建立纤维丝束模型结... 纤维输毛管的设计对粘胶纤维或Lyocell短纤维丝束的开松效果至关重要。为了探究纤维丝束在输毛管中的开松机理以及管道内流场状态对纤维运动状态的影响,采用三维建模软件建立输毛管流场模型,在商用软件Cradle CFD中建立纤维丝束模型结合流场进行耦合计算,研究分析了2000根长度为38 mm纤维丝束在输毛管中的运动过程。结果表明:在输毛管中纤维丝束受到流场作用的差异形成了纤维丝束运动的速度差,这是纤维丝束开松的主要原因;输毛管的竖直圆形管道处存在较大的压力梯度,使纤维丝束整体受到压力差异,也为纤维开松创造条件;输毛管的锥型管位置处的速度场较复杂,有利于纤维丝束开松;管径的变化导致产生漩涡,阻碍了纤维的输送。研究结果可为化纤与纺织行业输毛管设计提供参考。 展开更多
关键词 输毛管 流场模型 cradle CFD 纤维丝束 开松
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基于尺寸-拓扑耦合效应的火炮摇架轻量化设计
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作者 王猛 巩博瑞 +2 位作者 韩璇璇 罗苇杰 崔青春 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第8期95-101,共7页
火炮摇架是火力系统主要承重部件之一,其质量占比较大,轻量化设计是其减重和提高火炮机动性的重要手段。目前轻量化设计方法未虑及尺寸参数与拓扑结构间作用规律,以致火炮摇架难以达到最佳刚度质量比。为解决上述问题,提出了一种基于尺... 火炮摇架是火力系统主要承重部件之一,其质量占比较大,轻量化设计是其减重和提高火炮机动性的重要手段。目前轻量化设计方法未虑及尺寸参数与拓扑结构间作用规律,以致火炮摇架难以达到最佳刚度质量比。为解决上述问题,提出了一种基于尺寸-拓扑耦合效应的轻量化设计方法,通过正交设计与拓扑优化,生成不同尺寸火炮摇架的拓扑结构,采用响应面法构建表征尺寸参数、拓扑结构与刚度、质量映射的代理模型,利用智能算法开展全局优化,实现尺寸参数与拓扑结构同步轻量化设计。以某型火炮摇架为例进行分析,结果表明:相同刚度条件下,所提设计方法比原有方法得到的质量降低了10.8%,最大等效应力减小了35.8%。 展开更多
关键词 火炮摇架 轻量化设计 代理模型 拓扑优化
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中国语境下纯电动微型车全生命周期碳排放
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作者 郝旭 刘成荫 +4 位作者 姜禹彤 王贺武 邹岱江 钟锐恒 戴锋 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第1期47-53,共7页
为回答中国语境下纯电动微型车能够减碳多少,建立了针对中国语境下的纯电动微型车的全生命周期碳排放的评估模型。基于一组1030车·天的纯电动微型车的典型出行数据,使用了与交通有关的温室气体、排放及能耗的全生命周期碳排放核算... 为回答中国语境下纯电动微型车能够减碳多少,建立了针对中国语境下的纯电动微型车的全生命周期碳排放的评估模型。基于一组1030车·天的纯电动微型车的典型出行数据,使用了与交通有关的温室气体、排放及能耗的全生命周期碳排放核算模型—GREET,该模型包括:制造环节(CTG)、能源周期(WTW)和回收环节(GTC)。结果表明:中国内地纯电动微型车的日均出行里程37.2 km,73.1%的日出行里程低于50.0 km;在2021年平均电网、采用新欧洲驾驶循环(NEDC)的条件下,纯电动微型车全生命周期CO_(2)当量碳排放为26.8 t,比同级别内燃机汽车低约33%。其中的72%的排放来自纯电动微型车WTW环节,其CO_(2)当量碳排放为19.3 t。电网清洁化程度的提升和动力电池回收比例的增加,将有助于进一步降低纯电动微型车的碳排放。 展开更多
关键词 纯电动微型车 全生命周期碳排放 出行特征 GREET模型 制造环节(CTG) 能源周期(WTW) 回收环节(GTC)
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基于变密度法考虑制造约束的摇架拓扑优化设计
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作者 杨昆 陈红彬 陈龙淼 《火炮发射与控制学报》 北大核心 2024年第4期69-75,共7页
摇架是火炮的重要组成结构,摇架减重对火炮轻量化研究具有重要意义。以某122 mm口径火炮摇架为研究对象,以合理降低其质量为研究目的,利用有限元软件对其进行强度校核并结合变密度法拓扑优化理论进行了优化设计。优化时考虑可制造性对... 摇架是火炮的重要组成结构,摇架减重对火炮轻量化研究具有重要意义。以某122 mm口径火炮摇架为研究对象,以合理降低其质量为研究目的,利用有限元软件对其进行强度校核并结合变密度法拓扑优化理论进行了优化设计。优化时考虑可制造性对优化添加了拔模约束和对称约束等条件,使优化后结构更加合理,利于制造。优化后摇架结构质量减少了12.87%,材料利用率更高,对重构模型进行有限元校核,结果显示该优化结构仍旧可靠。结合增材制造技术对摇架拓扑优化结构进行对比实验,实验证明该拓扑优化对原有结构刚强度影响较小,具有一定合理性。 展开更多
关键词 摇架 变密度法 拓扑优化 拔模约束 增材制造
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