《运动医学与健康科学(英文)》(Sports Medicine and Health Science,SMHS)是由成都体育学院(CDSU)和中国体育科学学会(CSSS)联合主办的中国第一本运动医学领域的英文学术期刊[ISSN 2666-3376(Online)、ISSN 2097-6291(Print)、CN 51-18...《运动医学与健康科学(英文)》(Sports Medicine and Health Science,SMHS)是由成都体育学院(CDSU)和中国体育科学学会(CSSS)联合主办的中国第一本运动医学领域的英文学术期刊[ISSN 2666-3376(Online)、ISSN 2097-6291(Print)、CN 51-1812/R]。2019年12月创刊,所有文章在Elsevier的期刊平台ScienceDirect发布。期刊主要刊登运动医学与健康科学领域的新成果、新理论和新技术,包括原创研究、综述及述评类论文。展开更多
The reverse design of solid rocket motor(SRM)propellant grain involves determining the grain geometry to closely match a predefined internal ballistic curve.While existing reverse design methods are feasible,they ofte...The reverse design of solid rocket motor(SRM)propellant grain involves determining the grain geometry to closely match a predefined internal ballistic curve.While existing reverse design methods are feasible,they often face challenges such as lengthy computation times and limited accuracy.To achieve rapid and accurate matching between the targeted ballistic curve and complex grain shape,this paper proposes a novel reverse design method for SRM propellant grain based on time-series data imaging and convolutional neural network(CNN).First,a finocyl grain shape-internal ballistic curve dataset is created using parametric modeling techniques to comprehensively cover the design space.Next,the internal ballistic time-series data is encoded into three-channel images,establishing a potential relationship between the ballistic curves and their image representations.A CNN is then constructed and trained using these encoded images.Once trained,the model enables efficient inference of propellant grain dimensions from a target internal ballistic curve.This paper conducts comparative experiments across various neural network models,validating the effectiveness of the feature extraction method that transforms internal ballistic time-series data into images,as well as its generalization capability across different CNN architectures.Ignition tests were performed based on the predicted propellant grain.The results demonstrate that the relative error between the experimental internal ballistic curves and the target curves is less than 5%,confirming the validity and feasibility of the proposed reverse design methodology.展开更多
为了预防职业驾驶员肌肉骨骼疾病,促进职业健康,通过功能性动作筛查(functional movement screen,FMS)评估职业驾驶员功能性运动能力现状,进一步探讨运动干预效果。采用分层便利抽样法,选取145名职业驾驶员作为研究对象,通过FMS测试其...为了预防职业驾驶员肌肉骨骼疾病,促进职业健康,通过功能性动作筛查(functional movement screen,FMS)评估职业驾驶员功能性运动能力现状,进一步探讨运动干预效果。采用分层便利抽样法,选取145名职业驾驶员作为研究对象,通过FMS测试其功能性运动能力。随后,对其中20名女性驾驶员实施运动干预,全程监控其运动负荷,并在干预结束后进行FMS后测。通过SPSS 29.0软件分析FMS测试结果、性别间差异及运动干预效果。结果表明:职业驾驶员FMS总分普遍低于14分;单项测试中,主动直腿上抬动作得分最高,直线弓步蹲动作得分最低;深蹲、跨栏步、主动直腿上抬以及躯干稳定俯卧撑动作得分存在性别差异(P<0.05);干预后,女性驾驶员的基本功能动作、下肢柔韧性以及躯干稳定性动作模式明显改善,差异均有统计学意义(P<0.05);运动干预负荷整体属于中等强度有氧运动。可见,职业驾驶员的功能性运动能力普遍不足,中等强度的运动干预是改善女性驾驶员功能性运动能力、预防肌肉骨骼疾病的有效手段。展开更多
文摘《运动医学与健康科学(英文)》(Sports Medicine and Health Science,SMHS)是由成都体育学院(CDSU)和中国体育科学学会(CSSS)联合主办的中国第一本运动医学领域的英文学术期刊[ISSN 2666-3376(Online)、ISSN 2097-6291(Print)、CN 51-1812/R]。2019年12月创刊,所有文章在Elsevier的期刊平台ScienceDirect发布。期刊主要刊登运动医学与健康科学领域的新成果、新理论和新技术,包括原创研究、综述及述评类论文。
文摘The reverse design of solid rocket motor(SRM)propellant grain involves determining the grain geometry to closely match a predefined internal ballistic curve.While existing reverse design methods are feasible,they often face challenges such as lengthy computation times and limited accuracy.To achieve rapid and accurate matching between the targeted ballistic curve and complex grain shape,this paper proposes a novel reverse design method for SRM propellant grain based on time-series data imaging and convolutional neural network(CNN).First,a finocyl grain shape-internal ballistic curve dataset is created using parametric modeling techniques to comprehensively cover the design space.Next,the internal ballistic time-series data is encoded into three-channel images,establishing a potential relationship between the ballistic curves and their image representations.A CNN is then constructed and trained using these encoded images.Once trained,the model enables efficient inference of propellant grain dimensions from a target internal ballistic curve.This paper conducts comparative experiments across various neural network models,validating the effectiveness of the feature extraction method that transforms internal ballistic time-series data into images,as well as its generalization capability across different CNN architectures.Ignition tests were performed based on the predicted propellant grain.The results demonstrate that the relative error between the experimental internal ballistic curves and the target curves is less than 5%,confirming the validity and feasibility of the proposed reverse design methodology.
文摘为了预防职业驾驶员肌肉骨骼疾病,促进职业健康,通过功能性动作筛查(functional movement screen,FMS)评估职业驾驶员功能性运动能力现状,进一步探讨运动干预效果。采用分层便利抽样法,选取145名职业驾驶员作为研究对象,通过FMS测试其功能性运动能力。随后,对其中20名女性驾驶员实施运动干预,全程监控其运动负荷,并在干预结束后进行FMS后测。通过SPSS 29.0软件分析FMS测试结果、性别间差异及运动干预效果。结果表明:职业驾驶员FMS总分普遍低于14分;单项测试中,主动直腿上抬动作得分最高,直线弓步蹲动作得分最低;深蹲、跨栏步、主动直腿上抬以及躯干稳定俯卧撑动作得分存在性别差异(P<0.05);干预后,女性驾驶员的基本功能动作、下肢柔韧性以及躯干稳定性动作模式明显改善,差异均有统计学意义(P<0.05);运动干预负荷整体属于中等强度有氧运动。可见,职业驾驶员的功能性运动能力普遍不足,中等强度的运动干预是改善女性驾驶员功能性运动能力、预防肌肉骨骼疾病的有效手段。
