新规则下女子射箭个人项目成绩特征及启示          下载免费PDF全文

蔡勇 《河北体育学院学报》2019,33(3):62-67

运用文献资料法和专家访谈法，对新规则实施以来世界前八名女子射箭运动员的成绩特征进行分析，为我国女子射箭运动员的训练提供参考。结果表明：女子射箭项目排名赛成绩越高，在比赛中获得奖牌的概率越大，两者之间的关系具有统计学意义；中国女子射箭队个人项目后备力量薄弱，基础技术有待提高，目前难以打破韩国女子射箭队的统治地位；中国女子射箭运动员在世界大赛中的表现起伏较大，前三局的得分能力不强，需要加强开局得分能力的训练；为有效应对“远箭”局，发挥正常水平，需要加强运动员的心理训练和教练员的临场指挥能力。  相似文献   

Neighborhood crime undermines parenting: Violence in the vicinity of households as a predictor of aggressive discipline     

《Child abuse & neglect》2018

Child discipline is a central component of parent-child interactions. Evidence suggests corporal discipline impairs children’s physical, cognitive, and socioemotional development and compromises their future chances, especially since it is more frequently used against at-risk children. Using geocoded data for 1209 children under the age of five and their mothers, this study analyses the relation between the occurrence of crimes in close proximity to households in four major urban municipalities of Colombia and a particularly violent corporal discipline practice: hitting children with objects. Results indicate that exposure to violent crimes, such as homicides and personal injuries, predicts a higher probability of hitting children with objects, even after controlling for a set of individual, family, and neighborhood characteristics. Sensitivity analyses suggest violent crimes are not related to other discipline methods, and less threatening crimes, such as robbery and drug trafficking, are not associated with hitting children with objects. These findings suggest households’ walls are permeable, and outside threats may interfere with families’ dynamics and well-being. Future directions and implications are discussed.  相似文献   

Tracking user-role evolution via topic modeling in community question answering     

Chaogang Fu 《Information processing & management》2019,56(6):102075

Community question answering (CQA) services that enable users to ask and answer questions are popular on the internet. Each user can simultaneously play the roles of asker and answerer. Some work has aimed to model the roles of users for potential applications in CQA. However, the dynamic characteristics of user roles have not been addressed. User roles vary over time. This paper explores user representation by tracking user-role evolution, which could enable several potential applications in CQA, such as question recommendation. We believe this paper is the first to track user-role evolution and investigate its influence on the performance of question recommendation in CQA. Moreover, we propose a time-aware role model (TRM) to effectively track user-role evolution. With different independence assumptions, two variants of TRM are developed. Finally, we present the TRM-based approach to question recommendation, which provides a mechanism to naturally integrate the user-role evolution with content relevance between the answerer and the question into a unified probabilistic framework. Experiments using real-world data from Stack Overflow show that (1) the TRM is valid for tracking user-role evolution, and (2) compared with baselines utilizing role based methods, our TRM-based approach consistently and significantly improves the performance of question recommendation. Hence, our approach could enable several potential applications in CQA.  相似文献   

基于深度学习的中文专利自动分类方法研究   总被引：2，自引：0，他引：2  

吕璐成  韩涛  周健  赵亚娟 《图书情报工作》2020,64(10):75-85

[目的/意义] 面向当前国内专利审查和专利情报分析工作中对于海量专利分类的客观需求，设计了7种基于深度学习的专利自动分类方法，对比各种方法的分类效果，从而助力专利分类效率和效果的提升。[方法/过程] 针对传统机器学习方法存在的缺陷，基于Word2Vec、CNN、RNN、Attention机制等深度学习技术，考虑专利文本语序特征、上下文特征以及分类关键特征，设计Word2Vec+TextCNN、Word2Vec+GRU、Word2Vec+BiGRU、Word2Vec+BiGRU+TextCNN等7种深度学习模型，以中国专利为例，选取IPC主分类号的"部"作为分类依据，对比这7种模型与3种传统分类模型在中文专利分类任务中的效果。[结果/结论] 实证研究效果显示，采用考虑语序特征、上下文特征及强化关键特征的深度学习方法进行中文专利分类具有更优的分类效果。  相似文献   

基于二模复杂网络的隐性知识发现方法研究——以潜在药物靶点挖掘为例     

李东巧  陈芳  韩涛  杨艳萍  王学昭  王燕鹏  Cynthia Liu  Yingzhu Li 《图书情报工作》2020,64(21):120-129

[目的/意义] 通过构建二模复杂网络模型，揭示隐藏在海量文献中的隐性知识。[方法/过程] 通过NetworkX复杂网络工具包，依据任意两个节点的共现关系构建二模复杂网络模型；对网络模型中节点的共现关系进行加权，计算网络的拓扑信息并进行AP聚类，提取节点间的直接关系；采用AUC方法对AA、JC、加权改进的wAA和wJC等4种链路预测算法进行评价，遴选出最合适的预测算法，并对复杂网络的隐性关系进行预测分析。[结果/结论] 以潜在药物靶点挖掘为例进行的实证研究结果表明，wAA链路预测算法为最优的链路预测算法；二模复杂网络模型、指标和方法体系在美国化学文摘社数据库中的药物靶点挖掘中具有一定的有效性。下一步计划在其他数据库中或其他研究领域中进行尝试，以进一步验证该模型的通用性和有效性。  相似文献   

Parents’ son preference,childhood adverse experience and mental health in old age: Evidence from China     

《Child abuse & neglect》2019

BackgroundSon preference is an enduring phenomenon in China and may often be related to childhood adverse experiences. According to a life-course perspective, adverse experiences during a childhood period may have a long-term effect on mental health in later age. However, little is known about this relationship between parents’ son preference, childhood adverse experiences and adulthood mental health in China.ObjectiveThe study aims to evaluate the association of parents’ son preference and individual mental health in old age in China. The mediating role of childhood adverse experiences was also estimated.Participants and settingThe China Health and Retirement Longitudinal Study (CHARLS) 2015 combined with CHARLS life history survey was analyzed (N = 11,666).MethodsMental health was measured by a shortened modification of the Center for Epidemiologic Studies Depression scale including seven items, and higher scores indicated worse mental health status. A four-step mediating model was applied.ResultsRespondents growing in families with son preference had on average 0.75 (P < 0.001) points higher on the mental health scale than their counterparts, and the effects were consistent for both males and females. Childhood adverse experiences measured by physical maltreatment, emotional adverse experiences and witnesses of inter-parent violence mediated the relationship between parents’ son preference and individual adulthood mental health by 47.87%. For females, physical maltreatment and emotional adverse experiences explained the most parts of health effects of parents’ son preference, whereas witnesses of inter-parent violence was the most influential mediator for males.ConclusionParents’ son preference led to adverse childhood experiences, which influenced mental health in adulthood.  相似文献   

区域协同发展战略下京津冀体育产业一体化发展研究     

李艳荣  张长念 《广州体育学院学报》2019,(1):40-44

推动京津冀体育产业一体化发展，既是推进京津冀协同发展的重要内涵，也是体育领域落实区域协调发展战略的具体实践。研究表明，京津冀体育产业一体化发展，既面临难得的历史机遇，也面临着严峻的挑战。挑战在于：整体发展失衡，结构亟待优化；市场发育不足，行业竞争加剧；资源环境恶化，低碳锁定障碍；顶层设计不足，合作机制缺失。基于区域协调发展战略，应优化空间布局，推动体育产业错位发展；培育消费市场，推动体育产业创新发展；加快转型升级，推动体育产业低碳发展；完善合作机制，推动体育产业协同发展。  相似文献   

普通高校大学生形体礼仪课程实践与研究     

胡晓华  李欣  范莉莉  董菲 《体育科技文献通报》2020,(6):86-86,114

利用体育教育自身所承载的文化内涵及其独有的实践特征,整合资源,优化课程,将过去不同学科的形体训练与大学生形体礼仪、行为规范教育有机的容为一体。开设大学生形体礼仪课,指导大学生在塑造健康匀称,曲线、姿态优美,气质高雅的外部形态的同时按照社交礼仪规范来约束自己行为,真正做到“诚于中而行于外,慧于心而秀于言”,把内、外美有机地统一起来。为全面提升大学生素质教育开辟新的渠道。  相似文献   

线状需求下两阶段设施选址问题     

王紫萌  周建勤 《上海海事大学学报》2020,41(3):60-65

鉴于大型交通线路建设项目的物资需求随时间变化(在初期阶段需求较低;在后续阶段项目全面展开,需求显著上升),本文采用线积分对沿线连续分布的线状物资需求进行刻画,构建两阶段设施选址模型,第一阶段进行部分设施的选址,第二阶段对剩余设施选址,以实现系统总成本最低的目标。针对模型特点,设计基于Voronoi图的两阶段交替定位-分配(alternative location-allocation,ALA)算法进行求解,并进行实例分析,比较两阶段模型与传统模型的异同。研究表明,将两阶段设施选址模型应用于交通线路建设项目多物流节点选址,能节约运营成本,并缓解初期资金压力。  相似文献   

多旋翼无人机微多普勒特性分析与特征提取     

马娇  董勇伟  李原  李凌霄  杨杰芳 《中国科学院大学学报》2019,36(2):235-243

针对多旋翼无人机目标的识别问题，提出一种基于伽柏（Gabor）变换的瞬时频率估计与快速傅里叶变换（FFT）相结合的微多普勒特征提取算法。首先建立多旋翼无人机旋翼回波模型，并通过仿真分析叶片数目、旋翼转速和初始相位等参数对微多普勒特征的影响，利用Gabor变换得到时频特征。在此基础上通过瞬时频率极大值法提取微多普勒频率，并对瞬时频率采用FFT提取旋翼数和转动频率，从而获得叶片长度估计值。实测数据验证了该算法较为准确地提取无人机的微多普勒参数。  相似文献