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Surgical intervention combined with weight-bearing walking training promotes recovery in patients with chronic spinal cord injury:a randomized controlled study 被引量:1
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作者 Hui Zhu James D.Guest +19 位作者 Sarah Dunlop Jia-Xin Xie Sujuan Gao Zhuojing Luo Joe E.Springer Wutian Wu Wise Young Wai Sang Poon Song Liu Hongkun Gao Tao Yu Dianchun Wang Libing Zhou Shengping Wu Lei Zhong Fang Niu Xiaomei Wang Yansheng Liu Kwok-Fai So Xiao-Ming Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2773-2784,共12页
For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein th... For patients with chronic spinal cord injury,the co nventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection,pressure sores,osteoporosis,and deep vein thrombosis.Surgery is rarely perfo rmed on spinal co rd injury in the chronic phase,and few treatments have been proven effective in chronic spinal cord injury patients.Development of effective therapies fo r chronic spinal co rd injury patients is needed.We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal co rd injury to compare intensive rehabilitation(weight-bearing walking training)alone with surgical intervention plus intensive rehabilitation.This clinical trial was registered at ClinicalTrials.gov(NCT02663310).The goal of surgical intervention was spinal cord detethering,restoration of cerebrospinal fluid flow,and elimination of residual spinal cord compression.We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement,reduced spasticity,and more rapid bowel and bladder functional recovery than weight-bearing walking training alone.Overall,the surgical procedures and intensive rehabilitation were safe.American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries.Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients. 展开更多
关键词 chronic spinal cord injury intensive rehabilitation locomotor training neurological recovery surgical intervention weightbearing walking training
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ON THE EMPTY BALLS OF A CRITICAL OR SUBCRITICAL BRANCHING RANDOM WALK
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作者 Shuxiong ZHANG Jie XIONG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期2051-2072,共22页
Let{Z_(n)}_(n)≥0 be a critical or subcritical d-dimensional branching random walk started from a Poisson random measure whose intensity measure is the Lebesugue measure onℝ^(d).Denote by R_(n):=sup{u>0:Z_(n)({x∈ℝ... Let{Z_(n)}_(n)≥0 be a critical or subcritical d-dimensional branching random walk started from a Poisson random measure whose intensity measure is the Lebesugue measure onℝ^(d).Denote by R_(n):=sup{u>0:Z_(n)({x∈ℝ^(d):∣x∣<u})=0}the radius of the largest empty ball centered at the origin of Zn.In this work,we prove that after suitable renormalization,Rn converges in law to some non-degenerate distribution as n→∈.Furthermore,our work shows that the renormalization scales depend on the offspring law and the dimension of the branching random walk.This completes the results of Révész[13]for the critical binary branching Wiener process. 展开更多
关键词 empty ball DIMENSION branching random walk super-Brownian motion
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Mobility edges and localization characteristics in one-dimensional quasiperiodic quantum walk
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作者 崔鑫辉 王慧敏 李志坚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期156-160,共5页
We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization transition.The inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the m... We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization transition.The inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the mobility edge, a critical energy to distinguish the energy regions of extended and localized states. The analytical solution of mobility edge is obtained by the Lyapunov exponents in global theory, and the consistency of the two indexes is confirmed. We further study the dynamic characteristics of the quantum walk and show that the probabilities are localized to some specific lattice sites with time evolution. This phenomenon is explained by the effective potential of the Hamiltonian which corresponds to the phase in the coin operator of the quantum walk. 展开更多
关键词 quantum walk mobility edges QUASIPERIODICITY
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Strong invariance principle for a counterbalanced random walk
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作者 TAN Hui-qun HU Zhi-shui DONG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期370-380,共11页
We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 wit... We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n). 展开更多
关键词 random walk MARTINGALE invariance principle
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DeepSurNet-NSGA II:Deep Surrogate Model-Assisted Multi-Objective Evolutionary Algorithm for Enhancing Leg Linkage in Walking Robots
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作者 Sayat Ibrayev Batyrkhan Omarov +1 位作者 Arman Ibrayeva Zeinel Momynkulov 《Computers, Materials & Continua》 SCIE EI 2024年第10期229-249,共21页
This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective o... This research paper presents a comprehensive investigation into the effectiveness of the DeepSurNet-NSGA II(Deep Surrogate Model-Assisted Non-dominated Sorting Genetic Algorithm II)for solving complex multiobjective optimization problems,with a particular focus on robotic leg-linkage design.The study introduces an innovative approach that integrates deep learning-based surrogate models with the robust Non-dominated Sorting Genetic Algorithm II,aiming to enhance the efficiency and precision of the optimization process.Through a series of empirical experiments and algorithmic analyses,the paper demonstrates a high degree of correlation between solutions generated by the DeepSurNet-NSGA II and those obtained from direct experimental methods,underscoring the algorithm’s capability to accurately approximate the Pareto-optimal frontier while significantly reducing computational demands.The methodology encompasses a detailed exploration of the algorithm’s configuration,the experimental setup,and the criteria for performance evaluation,ensuring the reproducibility of results and facilitating future advancements in the field.The findings of this study not only confirm the practical applicability and theoretical soundness of the DeepSurNet-NSGA II in navigating the intricacies of multi-objective optimization but also highlight its potential as a transformative tool in engineering and design optimization.By bridging the gap between complex optimization challenges and achievable solutions,this research contributes valuable insights into the optimization domain,offering a promising direction for future inquiries and technological innovations. 展开更多
关键词 Multi-objective optimization genetic algorithm surrogate model deep learning walking robots
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从“走向自然”到“走向城市”:休闲美学视域下的City Walk
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作者 李灿垠 李社教 《湖北理工学院学报(人文社会科学版)》 2024年第4期54-60,共7页
“如何休闲”之问具有“顶天立地”的双重品格,既关乎具体可感的现实生活样态,又牵涉本己本真的存在与生命之思。以往,人们通过践履山水自然而追寻人性自然。而今,“走向自然”的休闲难以与日常生活相协调,亟待思考的是如何另辟蹊径。Ci... “如何休闲”之问具有“顶天立地”的双重品格,既关乎具体可感的现实生活样态,又牵涉本己本真的存在与生命之思。以往,人们通过践履山水自然而追寻人性自然。而今,“走向自然”的休闲难以与日常生活相协调,亟待思考的是如何另辟蹊径。City Walk是一种时兴的、以徒步为主要方式来探索城市空间、感受别样趣味的休闲活动,其低成本、慢节奏、益身心等特点极大地推动了休闲的开展,其“反叛技术”“背离秩序”的超越性品格规避了休闲异化的风险,其维持身心健康、促进友好交往、建构和谐关系及回归诗意栖居的美学价值助力人们属人地生存与属人地休闲。研究其活动特质与美学价值,既可为休闲美学添砖加瓦,又可为城市生活建言献策。 展开更多
关键词 City walk 城市漫步 休闲美学
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City Walk:美好生活视域下的体文旅融合发展研究
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作者 于兆楠 荆雯 《体育科技文献通报》 2024年第9期118-122,165,共6页
City Walk是一种以漫步为主要途径来体验城市风景和文化氛围的新型“微旅游”方式。本文在分析City Walk的内在机理及价值的基础上,对以美好生活视域下City Walk中体文旅融合所面临的现实困境与纾困路径进行分析。研究发现,City Walk中... City Walk是一种以漫步为主要途径来体验城市风景和文化氛围的新型“微旅游”方式。本文在分析City Walk的内在机理及价值的基础上,对以美好生活视域下City Walk中体文旅融合所面临的现实困境与纾困路径进行分析。研究发现,City Walk中体文旅融合的现实困境为缺乏相应科学健身知识储备、影响旅游目的地居民生活、过度商业化与文化原貌冲突、过于集中的City Walk路线。据此提出纾困路径:在人才支持方面要培育体文旅复合人才,组建专业队伍;在政策支持方面要完善法律法规,建立奖惩机制;在创新支持方面要持续探索新区域,助力体文旅高质量发展;在宣传支持方面要打造City Walk中的城市IP属性,扩大知名度。 展开更多
关键词 美好生活 City walk 体文旅 融合发展
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从City Walk到乡村旅游
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作者 丛洋 《中国农垦》 2024年第2期30-31,共2页
自2022年开始,一种名为City Walk(城市漫步)的旅行方式广受推崇,网上的路线攻略、结伴成团、报道评论越来越多。City Walk原是20世纪30年代发源于英国的一种城市旅游形式,指的是几个人在一起,在专业讲述员的带领下,有计划地行走在一条... 自2022年开始,一种名为City Walk(城市漫步)的旅行方式广受推崇,网上的路线攻略、结伴成团、报道评论越来越多。City Walk原是20世纪30年代发源于英国的一种城市旅游形式,指的是几个人在一起,在专业讲述员的带领下,有计划地行走在一条独特的道路上。但现在流行的这一概念更多指的是深入到城市的街巷、情境和空间,非功利化、无目的性地随意漫步游走,不受他人评价和引导的影响。 展开更多
关键词 乡村旅游 他人评价 walk 旅行方式 功利化
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Effect of Brisk Walking on Self-Care Agency or Care Dependency among Colorectal Cancer Patients with Permanent Stoma
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作者 Zhen Zhang Anabella G.Javier 《Journal of Clinical and Nursing Research》 2024年第5期68-82,共15页
Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study ... Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency. 展开更多
关键词 Permanent stoma Colorectal cancer Brisk walking Self-care agency Care dependency
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建筑可阅读 城市可漫步——以City Walk为“小切口”打开名城保护“大视野”
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作者 马向明 龚艳芬 陈奕铭 《城乡建设》 2024年第18期46-49,共4页
周末约上两三朋友,就近寻一处城市街头漫步,看看老建筑,逛逛特色小店,点一杯咖啡,或是品尝地道的当地小吃。这种生活方式被称为“City Walk”(意为“城市漫步”),已成为当下年轻人城市生活的新方式。“City Walk”指参与者行走在一条独... 周末约上两三朋友,就近寻一处城市街头漫步,看看老建筑,逛逛特色小店,点一杯咖啡,或是品尝地道的当地小吃。这种生活方式被称为“City Walk”(意为“城市漫步”),已成为当下年轻人城市生活的新方式。“City Walk”指参与者行走在一条独特的城市路线上,用脚步探索城市,深入城市肌理,感受城市独特气质的生活方式。根据《中国旅行消费趋势洞察白皮书(2023年版)》,2023年旅行消费的四大新趋势是“小众独特、自在松弛、未知惊喜、深度在地”. 展开更多
关键词 消费趋势 名城保护 城市肌理 walk 城市街头 大视野 小切口 独特气质
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Heat Kernel Estimates on Simple Random Walks and On-Diagonal Upper Bounds
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作者 Runquan Zuo Yuxiao Yan +2 位作者 Zishan Zhu Liwen Yao Qihao Han 《Journal of Applied Mathematics and Physics》 2024年第10期3613-3625,共13页
We primarily provide several estimates for the heat kernel defined on the 2-dimensional simple random walk. Additionally, we offer an estimate for the heat kernel on high-dimensional random walks, demonstrating that t... We primarily provide several estimates for the heat kernel defined on the 2-dimensional simple random walk. Additionally, we offer an estimate for the heat kernel on high-dimensional random walks, demonstrating that the heat kernel in higher dimensions converges rapidly. We also compute the constants involved in the estimate for the 1-dimensional heat kernel. Furthermore, we discuss the general case of on-diagonal estimates for the heat kernel. 展开更多
关键词 Heat Kernel Simple Random walk On-Diagonal Estimate
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基于Deep Walk-GATVAE的中小微企业服务推荐探析
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作者 张明亮 齐林 《数字技术与应用》 2024年第8期104-107,共4页
为了解决中小微企业在推荐服务时,因为企业节点表征使用One-hot编码维度过高导致服务推荐不准确的问题,提出了一种基于随机游走嵌入的图注意力变分自编码器网络模型(DeepWalk-GATVAE)的中小微企业服务推荐算法。首先是为解决数据的稀疏... 为了解决中小微企业在推荐服务时,因为企业节点表征使用One-hot编码维度过高导致服务推荐不准确的问题,提出了一种基于随机游走嵌入的图注意力变分自编码器网络模型(DeepWalk-GATVAE)的中小微企业服务推荐算法。首先是为解决数据的稀疏性,使用DeepWalk进行分布特征表示,并将特征转化为低维的表征;其次输入GATVAE网络模型挖掘企业和服务之间的关联;最后对使用的超参数进行调整,找到最优的参数选择。测试结果表明,本研究提出的算法ROC_AUC和AP值分别为0.8475和0.8626,与常见的推荐算法相比,提高了服务推荐的准确性,有效解决了中小微企业服务数据稀疏的问题。 展开更多
关键词 服务推荐 推荐算法 中小微企业 数据稀疏 网络模型 随机游走 超参数 walk
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Ground substrates classification and adaptive walking through interaction dynamics for legged robots 被引量:1
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作者 邵雪松 杨一平 王伟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第3期100-108,共9页
Adaptive locomotion in different types of surfaces is of critical importance for legged robots.The knowledge of various ground substrates,especially some geological properties,plays an essential role in ensuring the l... Adaptive locomotion in different types of surfaces is of critical importance for legged robots.The knowledge of various ground substrates,especially some geological properties,plays an essential role in ensuring the legged robots'safety.In this paper,the interaction between the robots and the environments is investigated through interaction dynamics with the closed-loop system model,the compliant contact model,and the friction model,which unveil the influence of environment's geological characteristics for legged robots'locomotion.The proposed method to classify substrates is based on the interaction dynamics and the sensory-motor coordination.The foot contact forces,joint position errors,and joint motor currents,which reflect body dynamics,are measured as the sensing variables.We train and classify the features extracted from the raw data with a multilevel weighted k-Nearest Neighbor(kNN) algorithm.According to the interaction dynamics,the strategy of adaptive walking is developed by adjusting the touchdown angles and foot trajectories while lifting up and dropping down the foot.Experiments are conducted on five different substrates with quadruped robot FROG-I.The comparison with other classification methods and adaptive walking between different substrates demonstrate the effectiveness of our approach. 展开更多
关键词 legged robot ground substrates classification adaptive walking interaction dynamics
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City Walk:小红书中的新媒介景观现象探略 被引量:4
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作者 曹忆静 《新媒体研究》 2023年第19期62-64,69,共4页
以小红书中的新媒介景观现象——CityWalk为研究对象,采用深度访谈和内容分析的研究方法,探析该现象产生的深层原因。研究发现,City Walk作为一种联系与纽带,代表着个体对原子化的抵抗;重构了“附近”的地方感和城市空间;同时,消解了社... 以小红书中的新媒介景观现象——CityWalk为研究对象,采用深度访谈和内容分析的研究方法,探析该现象产生的深层原因。研究发现,City Walk作为一种联系与纽带,代表着个体对原子化的抵抗;重构了“附近”的地方感和城市空间;同时,消解了社会加速下的焦虑感。然而,在追求美好生活过程中过度营造“精致感”,不仅不能消解身份焦虑,还会造成目标错位和价值观偏离。“伪精致”背后是消费主义的虚幻符号与“失真”现实,对此需要引导青年领悟实践幸福的正确道路,去“伪”存真,实现真正美好精致的生活。 展开更多
关键词 City walk 媒介景观 传播仪式观 加速社会 重回“附近” 消费社会
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WalK(S221P)突变促进金黄色葡萄球菌荚膜产生的作用研究
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作者 郭祖文 饶一凡 +1 位作者 彭华刚 饶贤才 《陆军军医大学学报》 CAS CSCD 北大核心 2023年第23期2460-2466,共7页
目的探究WalK(S221P)突变促进金葡菌荚膜产生的作用及可能机制。方法采用转录组测序(RNA-seq)分析WalK(S221P)突变对金葡菌基因表达的影响,采用RT-qPCR检测荚膜合成基因的表达变化。利用荚膜染色和透射电镜观察确认WalK(S221P)突变促进... 目的探究WalK(S221P)突变促进金葡菌荚膜产生的作用及可能机制。方法采用转录组测序(RNA-seq)分析WalK(S221P)突变对金葡菌基因表达的影响,采用RT-qPCR检测荚膜合成基因的表达变化。利用荚膜染色和透射电镜观察确认WalK(S221P)突变促进金葡菌荚膜产生的作用,再用RT-qPCR筛选参与介导WalK(S221P)促进荚膜合成的调控分子,通过结合位点分析和凝胶迁移阻滞实验(EMSA)证实WalKR对目标分子的调控作用。结果RNA-seq分析显示WalK(S221P)突变对196个金葡菌基因的表达水平影响显著,其中16个荚膜合成操纵子基因在XN108中的表达均显著上调。RT-qPCR检测显示荚膜合成相关capA,capH和capK在含有WalK(S221P)突变的XN108及K-Newman菌株中分别较回复株XN108-R和野生型Newman菌株显著上调。荚膜染色和透射电镜观察显示XN108的荚膜合成相比于回复株XN108-R明显增多,增厚。RT-qPCR筛选提示WalK(S221P)促进金葡菌荚膜合成可能是通过上调MgrA表达水平实现的,结合位点检索分析及EMSA实验证实WalK激活的WalR具有直接结合mgrA基因调控区的功能。结论金葡菌WalK(S221P)突变具有促进金葡菌荚膜产生的作用,该作用的发挥可能通过上调MgrA的表达而实现。 展开更多
关键词 金黄色葡萄球菌 荚膜 二元调控系统walkR walk(S221P) MgrA
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A Unique Discrete Wavelet&Deterministic Walk-Based Glaucoma Classification Approach Using Image-Specific Enhanced Retinal Images 被引量:1
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作者 Krishna Santosh Naidana Soubhagya Sankar Barpanda 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期699-720,共22页
Glaucoma is a group of ocular atrophy diseases that cause progressive vision loss by affecting the optic nerve.Because of its asymptomatic nature,glaucoma has become the leading cause of human blindness worldwide.In t... Glaucoma is a group of ocular atrophy diseases that cause progressive vision loss by affecting the optic nerve.Because of its asymptomatic nature,glaucoma has become the leading cause of human blindness worldwide.In this paper,a novel computer-aided diagnosis(CAD)approach for glaucomatous retinal image classification has been introduced.It extracts graph-based texture features from structurally improved fundus images using discrete wavelet-transformation(DWT)and deterministic tree-walk(DTW)procedures.Retinal images are considered from both public repositories and eye hospitals.Images are enhanced with image-specific luminance and gradient transitions for both contrast and texture improvement.The enhanced images are mapped into undirected graphs using DTW trajectories formed by the image’s wavelet coefficients.Graph-based features are extracted fromthese graphs to capture image texture patterns.Machine learning(ML)classifiers use these features to label retinal images.This approach has attained an accuracy range of 93.5%to 100%,82.1%to 99.3%,95.4%to 100%,83.3%to 96.6%,77.7%to 88.8%,and 91.4%to 100%on the ACRIMA,ORIGA,RIM-ONE,Drishti,HRF,and HOSPITAL datasets,respectively.The major strength of this approach is texture pattern identification using various topological graphs.It has achieved optimal performance with SVM and RF classifiers using biorthogonal DWT combinations on both public and patients’fundus datasets.The classification performance of the DWT-DTW approach is on par with the contemporary state-of-the-art methods,which can be helpful for ophthalmologists in glaucoma screening. 展开更多
关键词 Wavelet-transformation glaucoma classification deterministic tree walk graph-based features
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桑巴舞前进WALK步动作特征模型的构建与应用研究
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作者 杜辉 李雨露 李博 《体育科技》 2023年第3期12-14,共3页
以我国体育舞蹈优秀男选手完成的桑巴舞前进WALK动作为切入点,利用摄像技术获取其步动作视频,采用美国ARIEL三维图像解析系统对视频资料进行处理,得到其运动特征的相关运动学参数。依据体育舞蹈学、运动训练学和运动生物力学等学科的相... 以我国体育舞蹈优秀男选手完成的桑巴舞前进WALK动作为切入点,利用摄像技术获取其步动作视频,采用美国ARIEL三维图像解析系统对视频资料进行处理,得到其运动特征的相关运动学参数。依据体育舞蹈学、运动训练学和运动生物力学等学科的相关理论与方法,对该动作进行阶段和节点的划分,最终创建桑巴舞前进WALK步动作特征模型及相关参数标准。 展开更多
关键词 桑巴舞 前进walk 动作结构 特征模型
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巧用Star Walk2天文软件学习开普勒第三定律
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作者 文迅 周勋 《物理通报》 CAS 2023年第7期99-103,共5页
数据的收集和处理是科学素养的重要表现,其中蕴含着科学的思想和方法,也是科学素养培养的有效途径.关于开普勒第三定律的内容,教材只呈现了行星的运动遵循开普勒第三定律,对于围绕太阳公转的其他天体(如彗星)、甚至围绕行星运动的卫星... 数据的收集和处理是科学素养的重要表现,其中蕴含着科学的思想和方法,也是科学素养培养的有效途径.关于开普勒第三定律的内容,教材只呈现了行星的运动遵循开普勒第三定律,对于围绕太阳公转的其他天体(如彗星)、甚至围绕行星运动的卫星是否也遵循此定律则需探讨.借助天文软件“Star Walk2”(星空漫步)记录天体的信息优势,对上述问题进行科学再探究,学生通过数据处理的探究活动,从中领会科学思想与方法,促进科学素养的发展. 展开更多
关键词 开普勒第三定律 Star walk2 数据处理 科学素养
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A Wire-Driven Series Elastic Mechanism Based on Ultrasonic Motor for Walking Assistive System
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作者 Weihao Ren Hiroki Yoshioka +1 位作者 Lin Yang Takeshi Morita 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期179-190,共12页
In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assi... In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system. 展开更多
关键词 Ultrasonic motor WIRE-DRIVEN Series elastic mechanism walking assistive system Pulley Reduction ratio
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Role-Based Network Embedding via Quantum Walk with Weighted Features Fusion
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作者 Mingqiang Zhou Mengjiao Li +1 位作者 Zhiyuan Qian Kunpeng Li 《Computers, Materials & Continua》 SCIE EI 2023年第8期2443-2460,共18页
Role-based network embedding aims to embed role-similar nodes into a similar embedding space,which is widely used in graph mining tasks such as role classification and detection.Roles are sets of nodes in graph networ... Role-based network embedding aims to embed role-similar nodes into a similar embedding space,which is widely used in graph mining tasks such as role classification and detection.Roles are sets of nodes in graph networks with similar structural patterns and functions.However,the rolesimilar nodes may be far away or even disconnected from each other.Meanwhile,the neighborhood node features and noise also affect the result of the role-based network embedding,which are also challenges of current network embedding work.In this paper,we propose a Role-based network Embedding via Quantum walk with weighted Features fusion(REQF),which simultaneously considers the influence of global and local role information,node features,and noise.Firstly,we capture the global role information of nodes via quantum walk based on its superposition property which emphasizes the local role information via biased quantum walk.Secondly,we utilize the quantum walkweighted characteristic function to extract and fuse features of nodes and their neighborhood by different distributions which contain role information implicitly.Finally,we leverage the Variational Auto-Encoder(VAE)to reduce the effect of noise.We conduct extensive experiments on seven real-world datasets,and the results show that REQF is more effective at capturing role information in the network,which outperforms the best baseline by up to 14.6% in role classification,and 23% in role detection on average. 展开更多
关键词 Role-based network embedding quantum walk quantum walk weighted characteristic function complex networks
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