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Speed Testing of the Graviton and the Movement Track of Graviton in the Spiral Galaxy
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作者 Pingan Luo 《Journal of Modern Physics》 2013年第12期1614-1621,共8页
According to a series of hypothesis, for the spiral galaxy, a mathematical equation of the graviton movement track is built, it is also the central curve of the nebulae density distribution, which offers the method to... According to a series of hypothesis, for the spiral galaxy, a mathematical equation of the graviton movement track is built, it is also the central curve of the nebulae density distribution, which offers the method to measure the moving speed of the graviton. Using the observed images of the M51 galaxy, it confirms that the graviton movement curve in the spiral galaxy conforms to the image, QUOTE QUOTEis a constant. It points out that by measuring the rate of angular motion of the equivalent center in the galaxy, the real speed of the graviton can be estimated. Under the measuring condition of the M51,. The theory presented in this article also helps to calculate the rotation speed of a galaxy, provided the graviton speed is known for certain. With the model in this article and fitting data from the observation images of M51 galaxy, the guess which says “the moving speed of graviton is a constant” is supported unprecedentedly by observation data. It is for the first time that the upper limit of graviton speed, i.e. no more than times of light speed, is obtained from observation data. At the same time, the paper puts forward one possible way that the lower limit of graviton speed may be measured. And a new idea also brought forward in the paper is that the rotational angular velocity w of the equivalent center which plays an important role in a spiral galaxy may be measured according to the observed data of the thickness of galactic center of the spiral galaxy. 展开更多
关键词 Graviton Graviton SPEED movement track SPIRAL GALAXY M51 UPPER LIMIT of SPEED Super Velocity of Light
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Application of Eye Movement Analysis in Landscape Visual Quality Evaluation
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作者 Dewang LIU Xiaoyu HU +1 位作者 Xinhui HE Baoyong LI 《Meteorological and Environmental Research》 CAS 2023年第3期17-24,共8页
The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of exp... The existing methods of landscape visual quality evaluation is mostly based on people's subjective feelings,and the objectivity and scientificity of evaluation results are insufficient.As an important means of experimental psychology,eye movement technology can show great advantages and potential in landscape visual quality evaluation.On the basis of combing and summarizing the relevant literature,based on the explanation of the technical principle of eye movement analysis,the application field,research content,technical methods and other aspects of eye movement analysis were reviewed.The application prospect of eye movement technology in landscape visual quality evaluation was explored to provide theoretical reference for the in-depth evaluation and research of landscape visual quality evaluation theory. 展开更多
关键词 Eye movement analysis Eye movement tracking Landscape visual quality Visual perception EVALUATION
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MECHANICAL ANALYSIS OF ORBIT TRACKING MOVEMENT OF FEED SYSTEM IN LARGE SPHERICAL RADIO-TELESCOPE
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作者 刘明治 沈玉如 +1 位作者 刘军 那柏 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第9期1197-1203,共7页
The curve equation and its mechanics analysis of suspended-cable under the condition of end load are given. Then on the basis of it, the mechanical analysis of suspended-cable system for large spherical radio-telescop... The curve equation and its mechanics analysis of suspended-cable under the condition of end load are given. Then on the basis of it, the mechanical analysis of suspended-cable system for large spherical radio-telescope is studied, and procedures of the control for the orbit tracking movement of the line feed in large spherical radiotelescope are given. The validity of the results mentioned above is confirmed by means of computer simulations. 展开更多
关键词 curve equation of suspended-cable suspension mechanics large spherical radio-telescope orbit tracking movement control
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MonkeyTrail:A scalable video-based method for tracking macaque movement trajectory in daily living cages
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作者 Meng-Shi Liu Jin-Quan Gao +4 位作者 Gu-Yue Hu Guang-Fu Hao Tian-Zi Jiang Chen Zhang Shan Yu 《Zoological Research》 SCIE CAS CSCD 2022年第3期343-351,共9页
Behavioral analysis of macaques provides important experimental evidence in the field of neuroscience.In recent years,video-based automatic animal behavior analysis has received widespread attention.However,methods ca... Behavioral analysis of macaques provides important experimental evidence in the field of neuroscience.In recent years,video-based automatic animal behavior analysis has received widespread attention.However,methods capable of extracting and analyzing daily movement trajectories of macaques in their daily living cages remain underdeveloped,with previous approaches usually requiring specific environments to reduce interference from occlusion or environmental change.Here,we introduce a novel method,called MonkeyTrail,which satisfies the above requirements by frequently generating virtual empty backgrounds and using background subtraction to accurately obtain the foreground of moving animals.The empty background is generated by combining the frame difference method(FDM)and deep learning-based model(YOLOv5).The entire setup can be operated with low-cost hardware and can be applied to the daily living environments of individually caged macaques.To test MonkeyTrail performance,we labeled a dataset containing>8000 video frames with the bounding boxes of macaques under various conditions as ground-truth.Results showed that the tracking accuracy and stability of MonkeyTrail exceeded that of two deep learningbased methods(YOLOv5 and Single-Shot MultiBox Detector),traditional frame difference method,and na?ve background subtraction method.Using MonkeyTrail to analyze long-term surveillance video recordings,we successfully assessed changes in animal behavior in terms of movement amount and spatial preference.Thus,these findings demonstrate that MonkeyTrail enables low-cost,large-scale daily behavioral analysis of macaques. 展开更多
关键词 movement trajectory tracking Video-based behavioral analyses Background subtraction Virtual empty background OCCLUSION
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Eye Movement Modeling Examples as a Teaching Tool for Epidural Block
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作者 Emanuele Capogna Marco Scorzoni +5 位作者 Gian Luigi Gonnella Matteo Velardo Pier Paolo Giurì Mariano Ciancia Gaetano Draisci Giorgio Capogna 《Open Journal of Anesthesiology》 2023年第4期75-84,共10页
Introduction: Video examples with task demonstrations by experts, with the expert’s eye movements superimposed on the task, are known as “eye movement modeling examples” (EMME). We performed this study to evaluate ... Introduction: Video examples with task demonstrations by experts, with the expert’s eye movements superimposed on the task, are known as “eye movement modeling examples” (EMME). We performed this study to evaluate if there were improvements in the performance of anesthesia novice trainees when executing the epidural technique after an EMME of epidural block procedure. Methods: We developed an eye movement modeling example (EMME) from eye tracking recordings made by experienced anesthesiologists with more than 20 years of experience. Forty-two PGY3 anesthesia trainees who had never previously performed an epidural block were randomized to receive (study group) or not receive (control group) the EMME video before their institutional training. All the trainees were evaluated every 10 epidural blocks until the end of the rotation period, by an independent, blinded observer using the Global Rating Scale for Epidural Anesthesia (GRS). Results: Trainees who received the EMME training exhibited more respect for the patient’s tissues (P Discussion: This is the first study that has used the EMME for a practical, clinical teaching purpose on real patients and that has used it as an aid in teaching epidural anesthesia. We demonstrated that inexperienced trainees who received the EMME training improved their proficiency at epidural blocks as compared to those who had no EMME training beforehand. Given this result, we welcome further studies to investigate the impact and the role of EMME on clinical teaching in the field of anesthesia. 展开更多
关键词 Eye tracking Eye movement Modeling Example Epidural Anesthesia
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基于学生眼动数据的线上教学课件学习效果分析及优化
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作者 胡瑾秋 肖尚蕊 《教育教学论坛》 2024年第12期5-12,共8页
随着线上教学资源的日渐丰富以及特殊的学习环境要求,直播、录播课教学发展迅猛,有别于传统线下教学师生面对面授课,线上教学环境嘈杂,学生注意力易被分散。为提高高校学生线上学习效率,通过合理科学的线上教学课件“图、文、公式、标... 随着线上教学资源的日渐丰富以及特殊的学习环境要求,直播、录播课教学发展迅猛,有别于传统线下教学师生面对面授课,线上教学环境嘈杂,学生注意力易被分散。为提高高校学生线上学习效率,通过合理科学的线上教学课件“图、文、公式、标题”排版,优化教师线上教学课件。利用桌面眼动仪和录制的教学视频模拟学生线上学习环境,追踪实验对象观看教学课件时的眼动,分析眼动行为,获取眼动数据,并对实验对象在线上教学后的一小时和一周的两个时间节点进行学习内容测试,从学习理解深度、学习记忆深度以及学习应用能力等三个方面评价学生在不同设计课件下的学习效率,利用评价结果与课件设计要素的配对t检验获取最优的线上教学课件设计方案。 展开更多
关键词 线上教学 视线追踪 眼动数据 学习效果 PPT课件
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拖拉机平视显示研究与分析--基于DeeplabV3+和眼动追踪技术
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作者 邴媛 张建敏 《农机化研究》 北大核心 2024年第6期240-247,共8页
为了提高拖拉机驾驶人员的驾驶安全系数,解决拖拉机驾驶人员经常扭头观看后方农机机具作业情况的问题,对拖拉机驾驶室使用平视显示(HUD)进行研究分析。首先,利用Deeplabv3+图像语义分割法与眼动追踪技术结合的方式,对拖拉机驾驶人员观... 为了提高拖拉机驾驶人员的驾驶安全系数,解决拖拉机驾驶人员经常扭头观看后方农机机具作业情况的问题,对拖拉机驾驶室使用平视显示(HUD)进行研究分析。首先,利用Deeplabv3+图像语义分割法与眼动追踪技术结合的方式,对拖拉机驾驶人员观察后方农机机具的画面进行采集并对重要信息进行标注;然后,使用Pytorch深度学习框架来搭建所需的模型网络结构和完成相应的代码开发,最终得到较为清晰的分割图像;最后,对原始图像及分割后图像进行眼动追踪实验验证,提取被试者的眼动轨迹,发现分割后图像能更好地被观看者识别。研究结果表明:利用DeeplabV3+对图像进行分割增强,应用到平视显示技术中,可以有效提高拖拉机驾驶人员的驾驶安全性和工作效率。 展开更多
关键词 拖拉机 平视显示 DeeplabV3+ 眼动追踪 深度学习
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CrowdTracker:一种基于移动群智感知的目标跟踪方法 被引量:12
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作者 景瑶 郭斌 +3 位作者 陈荟慧 岳超刚 王柱 於志文 《计算机研究与发展》 EI CSCD 北大核心 2019年第2期328-337,共10页
面向目标跟踪问题提出一种基于移动群智感知的解决方案CrowdTracker.不同于基于视频监控的目标跟踪方法,通过基于群智的多人协作拍照方式实现对移动目标的轨迹预测和跟踪,其优化目标为在保证准确实时地对目标进行跟踪的同时尽可能地减... 面向目标跟踪问题提出一种基于移动群智感知的解决方案CrowdTracker.不同于基于视频监控的目标跟踪方法,通过基于群智的多人协作拍照方式实现对移动目标的轨迹预测和跟踪,其优化目标为在保证准确实时地对目标进行跟踪的同时尽可能地减少用户激励的成本(假设激励与完成任务的参与者人数和参与者完成任务所移动的距离成正比).为实现该目标,提出了目标移动性预测的方法MPRE和任务分配的方法T-centric,P-centric.T-centric是以任务为中心的参与者选择方法,而P-centric是以人为中心的任务选择方法.MPRE通过分析大量的车辆历史轨迹建立城市里车辆的移动模型以预测目标下一步的位置.在预测的区域内通过T-centric或P-centric方法进行跟踪任务分配.通过一个大规模的真实数据集对移动性预测方法MPRE和2种任务分配算法进行实验评估,实验结果表明:CrowdTracker能有效地在实现目标实时跟踪的同时降低激励成本. 展开更多
关键词 移动群智感知 拍照 目标跟踪 目标移动性预测 任务分配
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南海北部扩张的地表过程响应:来自海南岛五指山的磷灰石裂变径迹年龄证据
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作者 史军华 韩帅 +3 位作者 杜建军 韩建恩 孙东霞 胡道功 《地质学报》 EI CAS CSCD 北大核心 2024年第2期421-432,共12页
海南岛是南海地块的重要组成部分,其构造演化很大程度上能够反映整个南海的构造活动特征。新生代,海南岛在新构造运动作用下,断块差异升降比较明显,形成了大致以王五-文教断裂为界,北为沉降区,南为断隆区的构造格局。对断隆区隆升过程... 海南岛是南海地块的重要组成部分,其构造演化很大程度上能够反映整个南海的构造活动特征。新生代,海南岛在新构造运动作用下,断块差异升降比较明显,形成了大致以王五-文教断裂为界,北为沉降区,南为断隆区的构造格局。对断隆区隆升过程的研究能够帮助揭示海南岛新构造活动历史,但至今为止,琼中南山地隆升的原因和时限仍存在争议。为了厘清海南岛中部的剥露隆升事件,本文选择琼中南地区海拔最高、高差最大的五指山为研究区,采集8组高程岩石样品,高程范围为203.55~1153.52 m。对采集的样品进行了磷灰石裂变径迹测试和热历史模拟分析,结果表明海南岛五指山地区新生代主要经历了两期快速隆升剥露。第一期为渐新世—中新世(32~17 Ma):隆升速率较快,此时期太平洋板块向欧亚板块俯冲后撤,南海正经历第二次扩张,使得海南岛拉张,活动强烈,造成琼中山地区快速隆升,直到中中新世转为缓慢隆升。第二期为中新世末期(5 Ma)的快速剥蚀隆升阶段:南海扩张已经结束,随着菲律宾板块俯冲亚洲板块,南海北部陆缘整体处于加速热沉降阶段,且全球气候变化加快,造成了海南岛广泛的隆起和加速剥蚀。 展开更多
关键词 裂变径迹 新生代构造运动 隆升与剥露历史 海南岛 五指山
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基于眼动信号的感兴趣检测方法研究
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作者 王新志 曾洪 +1 位作者 张华宇 宋爱国 《传感器与微系统》 CSCD 北大核心 2024年第3期14-17,共4页
为了使机器智能达到人类的识别能力,需要提供标注的难例样本。常用的键盘、鼠标等标注方式效率较低,基于眼动信号的标注方式无需手动操作,但目前研究多采用依赖特征工程的浅层模型实现感兴趣检测以标注样本。针对浅层模型存在的问题,基... 为了使机器智能达到人类的识别能力,需要提供标注的难例样本。常用的键盘、鼠标等标注方式效率较低,基于眼动信号的标注方式无需手动操作,但目前研究多采用依赖特征工程的浅层模型实现感兴趣检测以标注样本。针对浅层模型存在的问题,基于特征通道权重重分配多尺度残差网络模型对注视序列分类以实现感兴趣检测,并通过对比实验验证本文方法的有效性。实验结果表明:提出的多尺度残差网络模型分类精度达到96%,较现有基于浅层模型的方法和未改进的基于深层模型的方法,显著提升了感兴趣检测的精度和鲁棒性。 展开更多
关键词 视线追踪 眼动事件检测 时间序列分类 多尺度残差网络 感兴趣检测
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从追踪学生的答题眼动轨迹积累内容效度证据——以高考语文试题为例
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作者 余航 《考试研究》 2024年第2期52-61,共10页
效度如何得到有效的评估是教育测量中的一个重要问题。为了有效评估中高考等高利害考试的试题效度,以语文学科为例,在学生作答往年试题过程中采用红外线眼动仪,追踪学生审读题目要求和作答的思维轨迹,为学生答题思维过程画像。眼动仪监... 效度如何得到有效的评估是教育测量中的一个重要问题。为了有效评估中高考等高利害考试的试题效度,以语文学科为例,在学生作答往年试题过程中采用红外线眼动仪,追踪学生审读题目要求和作答的思维轨迹,为学生答题思维过程画像。眼动仪监测答题过程的一系列心理反应数据和后期学生访谈记录生成作答的心理反应样本。将这些数据样本与命题人所期待的测量目标进行对比后发现:有部分试题所希望测量的知识点、能力点与学生实际的心理反应偏差较大。建议依据被试面对不同刺激材料时的眼动轨迹和心理反应的有关数据,建立一个相对完善的试题效度检测系统,从而在试题设计上减少“噪声”;并在日常教学中以被评价者视角增强“评价对焦”。 展开更多
关键词 眼动轨迹 心理反应 高考语文试题 内容效度
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基于车载环境的交通目标跟踪
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作者 孟令辰 孟乔 +1 位作者 皇甫俊逸 李鑫 《计算机系统应用》 2024年第3期63-72,共10页
针对车载环境下小目标难以识别和相机动态移动造成的目标跟踪精度下降问题,提出一种基于改进YOLOv5与ByteTrack的交通目标跟踪方法.首先,引入Transformer与加权特征金字塔(BiFPN)结构的思想重构YOLOv5检测网络,有效捕获了特征的全局依... 针对车载环境下小目标难以识别和相机动态移动造成的目标跟踪精度下降问题,提出一种基于改进YOLOv5与ByteTrack的交通目标跟踪方法.首先,引入Transformer与加权特征金字塔(BiFPN)结构的思想重构YOLOv5检测网络,有效捕获了特征的全局依赖关系,缓解了深层卷积小目标信息丢失问题,改善了车载环境下的目标检测性能.此后,以ByteTrack为基础提出了添加相机移动补偿的CMC-ByteTrack跟踪方法,更精准地描述了视频前后帧的数据关联关系,提高了相机大幅位移时的跟踪精度.实验结果表明,改进YOLOv5的平均检测精度(mAP)达到了82.2%,相比原算法提高了3.9%,与CMC-ByteTrack结合后的跟踪准确性(MOTA)相比改进前的跟踪方法提高了2.8%. 展开更多
关键词 YOLOv5 目标跟踪 TRANSFORMER 特征融合 相机移动补偿
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基于眼动追踪技术的教学视频眼动分析系统
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作者 柳晓龙 钟节辉 《河南财政金融学院学报(自然科学版)》 2024年第1期26-31,共6页
设计了可兼容大部分眼动仪的教学视频眼动分析系统,并从眼动数据记录、动态兴趣区定义、眼动分析3个模块,探讨了教学视频眼动分析系统的实现机制。该系统有助于提高眼动分析在教育领域应用的普适性,降低研究者在眼动相关方向的研究成本。
关键词 眼动分析 眼动追踪 教学视频 数据分析 视频分析
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High resolution tracking of adult horseshoe crabs Limulus polyphemus in a New Hampshire estuary using fixed array ultrasonic telemetry 被引量:8
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作者 Winsor H.WATSON Ⅲ Christopher C.CHABOT 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第5期599-610,共12页
While several studies have documented the large-scale,seasonal movements of horseshoe crabs,little is known abouttheir fine-scale,daily movement patterns.In this study we used a fixed array ultrasonic telemetry system... While several studies have documented the large-scale,seasonal movements of horseshoe crabs,little is known abouttheir fine-scale,daily movement patterns.In this study we used a fixed array ultrasonic telemetry system to track the movementsof 12 male and 16 female horseshoe crabs in the Great Bay estuary,New Hampshire.Data were obtained during the mating season,as well as during the remainder of the summer and fall,in the years 2005-2008.During the mating season animals were often,but not always,active during the high tides when they were approaching and leaving the spawning beaches.On average,bothmales and females approached mating beaches during 33% of the high tides they experienced and they most often made the transitionfrom being inactive to active during the last two hours of an incoming tide.From April-October horseshoe crabs were significantlymore active during high tide periods vs low tide periods,with no clear preference for diurnal vs nocturnal activity.Afterthe mating season ended horseshoe crabs continued to move into shallower water at high tide and then return to deeper water atlow tide.Observations by SCUBA divers suggest that during these excursions into the mudflats horseshoe crabs were digging pitsin the sediment while foraging for food.Thus,the tidal rhythm of activity that has been so well documented during the matingseason probably persists into the fall,and primarily involves foraging 展开更多
关键词 遥测系统 超声波 布什 跟踪 河口 成人 觅食活动 季节性
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The linear position tracking servo systemusing a linear voice-coil motor 被引量:2
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作者 褚立新 林辉 《Journal of Pharmaceutical Analysis》 SCIE CAS 2008年第3期164-167,共4页
More and more linear servo systems have been used in servo applications. Direct drive technology can greatly increase the bandwidth and the tracking accuracy. A position servo-system based on linear voice-coil motor w... More and more linear servo systems have been used in servo applications. Direct drive technology can greatly increase the bandwidth and the tracking accuracy. A position servo-system based on linear voice-coil motor was designed for one linear oscillation movement application. Besides the conventional position, speed and current control loops, the speed and acceleration feed-forward control of command position signal were also used. The experimental test proved the correctness of the design, and the system can track the given periodic sinusoid position command signal of 15Hz with high accuracy. The linear voice-coil motor is very suitable for short stroke position tracking application with high dynamic response. 展开更多
关键词 voice-coil motor position tracking linear movement
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碳标签信息传递对消费者绿色购买行为的影响--来自眼动追踪实验的证据
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作者 梅蕾 孙立峰 +1 位作者 张鹏 李文 《林业经济》 北大核心 2023年第5期75-96,共22页
厘清碳标签所传递的绿色信息对消费者购买行为的影响,有助于推进我国的绿色消费。文章以绿色食品为例,设计三组2×2混合实验,利用眼动追踪技术获取被试者注视和行为数据,并采用双因素分析方法,探究碳标签信息传递相关因素和心理认... 厘清碳标签所传递的绿色信息对消费者购买行为的影响,有助于推进我国的绿色消费。文章以绿色食品为例,设计三组2×2混合实验,利用眼动追踪技术获取被试者注视和行为数据,并采用双因素分析方法,探究碳标签信息传递相关因素和心理认知程度对消费者视觉注意(注视总持续时长和注视次数)和购买选择行为的影响。研究发现:(1)被试者对有碳标签、产品溢价和位于包装正面的碳标签的总注视时间更长且注视次数更多(p<0.01)。(2)碳标签相关因素对视觉注意的影响受到认知程度的调节,认知程度与有无碳标签和产品溢价的交互作用均显著(p<0.01)。(3)高认知组被试者选择碳标签产品的次数占比(87.57%、70.06%)大于低认知组被试者选择次数占比(64.97%、56.50%),并且显著性水平p<0.01,表明碳标签认知的提高会对被试者选择贴有碳标签的产品产生显著正向影响。(4)消费者对碳标签产品的注意效果与购买行为具有一致性。文章在认知-情感-行为模型的基础上引入视觉注意理论,采用神经营销实验方法开展绿色信息传递对消费者购买影响机理的研究,并考虑了认知的调节作用。文章提出要从碳标签诠释的客观信息出发,提高其绿色信息传递效率;同时,通过开展全媒体、立体化宣传和舆论引导推广碳标签产品的知识和信息,提升消费者对碳标签的认知水平,助力我国碳标签推广和《促进绿色消费实施方案》的落实。 展开更多
关键词 碳标签 绿色购买 产品溢价 认知程度 眼动追踪
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基于数据融合的全向移动机器人轨迹跟踪研究
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作者 郑志娴 郑晶 陈小娥 《兰州文理学院学报(自然科学版)》 2023年第4期35-39,共5页
为了提高对电动液压驱动全向移动机器人的轨迹跟踪控制能力,提出基于数据融合的全向移动机器人轨迹跟踪方法.构建全向移动机器人的人与环境交互动力学驱动模型及机器人的运动学参数模型,采用多自由度多模型的分层运动控制方法实现对机... 为了提高对电动液压驱动全向移动机器人的轨迹跟踪控制能力,提出基于数据融合的全向移动机器人轨迹跟踪方法.构建全向移动机器人的人与环境交互动力学驱动模型及机器人的运动学参数模型,采用多自由度多模型的分层运动控制方法实现对机器人的位姿参数数据融合跟踪识别,提取机器人轨迹跟踪的动态模型参数.通过对机器人移动过程中的步频、周期等参数估计,采用机构自由度和运动复杂性参数融合估计的方法,构建机器人轨迹跟踪控制的联合协同参数解算模型,根据参数优化解析结果,以躯体平衡与环境自适应控制为最优化约束条件,实现机器人轨迹跟踪控制优化.仿真结果表明:采用该方法进行全向移动机器人轨迹跟踪的自适应性较好,振荡抑制能能力较强,提高了机器人全向移动的稳定性和鲁棒性. 展开更多
关键词 数据融合 全向移动 机器人 轨迹跟踪 力学驱动
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基于空间光传感信息的运动姿态实时跟踪分析与研究
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作者 董晓起 吴煜煌 《激光杂志》 CAS 北大核心 2023年第8期206-210,共5页
为了排除运动动态性干扰,探讨人体运动下空间光传感信息可作为视觉跟踪特征的可行性,建立起空间三维点与运动姿态对应点的关系,通过计算运动姿态目标点的投影,对摄像机进行标定,根据人体运动动作点的标定,采集到人体运动姿态空间光传感... 为了排除运动动态性干扰,探讨人体运动下空间光传感信息可作为视觉跟踪特征的可行性,建立起空间三维点与运动姿态对应点的关系,通过计算运动姿态目标点的投影,对摄像机进行标定,根据人体运动动作点的标定,采集到人体运动姿态空间光传感特征,通过提取运动姿态特征,根据人体运动姿态光传感样本点的逆映射原理,重构运动姿态图像,实现运动姿态的实时跟踪。实验结果表明,基于空间光传感信息的运动姿态实时跟踪的横向偏移量还是跟踪准确率方面,都不会受到运动姿态的动态性影响,跟踪方法的准确率可达到1.0,跟踪效率高达0.1,具有更好的稳定性。 展开更多
关键词 空间光传感信息 运动姿态 实时跟踪 摄像机 图像采集 融合处理
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帕德玛大桥铁路连接线无砟轨道系统设计
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作者 杨文茂 林红松 +1 位作者 徐浩 代丰 《铁道工程学报》 EI CSCD 北大核心 2023年第12期36-40,共5页
研究目的:帕德玛大桥铁路连接线是孟加拉国首条铺设无砟轨道的铁路,也是我国工程技术人员首次在120 km/h、25 t轴重客货共线条件下开展的大跨钢桁梁上无砟轨道设计和简支梁上无砟道岔设计,设计过程中面临着结构限界和轨道自重受限、2350... 研究目的:帕德玛大桥铁路连接线是孟加拉国首条铺设无砟轨道的铁路,也是我国工程技术人员首次在120 km/h、25 t轴重客货共线条件下开展的大跨钢桁梁上无砟轨道设计和简支梁上无砟道岔设计,设计过程中面临着结构限界和轨道自重受限、2350 mm超宽梁缝及7.5‰超大梁端转角、简支梁上无砟无缝道岔群布设等难题,亟需对轨道结构及部件开展系统研究,以指导铺轨实践。研究结论:(1)提出了底座板与桥面板一体化设计的单层长枕埋入式无砟轨道,克服了大跨度钢桁梁上结构限界和轨道自重受限的难题;(2)研发了±800 mm调整量梁端伸缩装置及钢轨伸缩调节器一体化装置,解决了2350 mm宽梁缝、7.5‰梁端转角条件下的轨道结构自适应调整问题;(3)基于“岔梁墩一体化”模型开展了岔桥相互作用分析,解决了25 t轴重条件下简支梁上的无砟无缝道岔群设计难题;(4)上述创新实践指导了孟加拉国首条无砟轨道铺设,对海外工程复杂桥梁结构上无砟轨道设计具有一定的参考作用。 展开更多
关键词 大跨钢桁梁桥 无砟轨道 梁端伸缩装置 钢轨伸缩调节器 无缝道岔
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Deficit of pursuit ocular movements in early Alzheimer's disease
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作者 Francesco Cordici Pietro Lanzafame +5 位作者 Silvia Marino Alessandro Celona Lilla Bonanno Annalisa Baglieri Alessia Bramanti Placido Bramanti 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第20期1583-1586,共4页
Previous studies have demonstrated that advanced Alzheimer's disease(AD)patients have deficiency of eye movements.However,there have been no reports on eye movement in the early stages of AD.The aim of this study w... Previous studies have demonstrated that advanced Alzheimer's disease(AD)patients have deficiency of eye movements.However,there have been no reports on eye movement in the early stages of AD.The aim of this study was to evaluate pursuit ocular movements(POM)provided by a vision-based non-intrusive eye tracker in patients with early AD.POM values were significantly lower in AD patients than in normal controls(P 〈 0.01).In AD patients,POM values were not closely correlated with the Mini-Mental State Examination scores(P = 0.3).There was no significant difference in POM values among patients treated with or without anticholinesterase therapy.We used a vision-based method,for non-intrusive eye tracking,which can be proposed as a possible tool for supporting the diagnosis of early AD. 展开更多
关键词 Alzheimer's disease early diagnosis pursuit ocular movements smooth pursuit dysfunctions vision-based eye tracking system
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