直线贴标机使用中存在的问题及改进措施

文章简述直线贴标机的安装、调试、试运行全过程;直线贴标机的工作原理和组成机构,及设备使用中遇到的问题及解决的办法等。     

基于SolidWorks的抛丸机用提升机的设计

利用Solidworks软件进行提升机上部传动和下部传动主要部件的设计,并利用其焊件模块进行了机罩设计,应用其装配功能,将各个部件装配成总装部件,达到了设计目的,提高了设计效率,缩短了产品的设计制造周期,取得了较大的经济效益。     

高精度步距规在检验数控机床时的突出优势

介绍高精度步距规的特点及其检验数控机床的优势,提出相关建议。     

A comparison of accelerometry analysis methods for physical activity in older adult women and associations with health outcomes over time

ABSTRACT

This study compared five different methods for analyzing accelerometer-measured physical activity (PA) in older adults and assessed the relationship between changes in PA and changes in physical function and depressive symptoms for each method. Older adult females (N = 144, M_age = 83.3 ± 6.4yrs) wore hip accelerometers for six days and completed measures of physical function and depressive symptoms at baseline and six months. Accelerometry data were processed by five methods to estimate PA: 1041 vertical axis cut-point, 15-second vector magnitude (VM) cut-point, 1-second VM algorithm (Activity Index (AI)), machine learned walking algorithm, and individualized cut-point derived from a 400-meter walk. Generalized estimating equations compared PA minutes across methods and showed significant differences between some methods but not others; methods estimated 6-month changes in PA ranging from 4 minutes to over 20 minutes. Linear mixed models for each method tested associations between changes in PA and health. All methods, except the individualized cut-point, had a significant relationship between change in PA and improved physical function and depressive symptoms. This study is among the first to compare accelerometry processing methods and their relationship to health. It is important to recognize the differences in PA estimates and relationship to health outcomes based on data processing method.

Abbreviation: Machine Learning (ML); Short Physical Performance Battery (SPPB); Center of Epidemiologic Studies Depression Scale (CES-D); Physical Activity (PA); Activity Index (AI); Activities of Daily Living (ADL)     

Analysing expertise through data mining: an example based on treading water

Abstract

A classification system of treading water based on a conceptual typology was first established and then verified empirically. The typology was established on two concepts: the nature of the forces created within the water and the type of inter-limb coordination used. Thirty-eight participants were videotaped while treading water. Multivariate statistics were used to understand how the different behavioural types related to expertise. Three distinct groups of coordination patterns were adopted during treading water. A support vector machine procedure was used as a confirmatory procedure. The data mining process provides a methodological framework to analyse expertise in sports activities, and in this context suggests that a taxonomy can be established among the numerous coordination solutions that allow humans to create stabilising forces in the water.     

基于机器学习的旅游推介系统的设计

个性化的旅游服务往往能得到客户更多的关注。潜在客户对旅行社计划推出的旅游线路的关注信息,常出现在留言板上或者关于旅游线路或景点的投票页上,利用这些信息,借助文本挖掘和机器学习技术,可以找出最适合推荐给潜在客户的旅游线路,从而实现旅游服务（线路）的推介。     

带同类恶化工件机器排序的多用户模型

We consider a scheduling problem involving a single processor utilized by two customers with constant deteriorating jobs,i.e.,jobs whose processing times are an increasing function of their starting times.Traditionally,such scenarios are modeled by assuming that each customer has the same criterion.In practice,this assumption may not hold.Instead of using a single criterion,we examine the implications of minimizing an aggregate scheduling objective function in which jobs belonging to different customers are evaluated with their individual criteria.We examine three basic scheduling criteria:minimizing makespan,minimizing maximum lateness,and minimizing total weighted completion time.We demonstrate all the scheduling problems considered are polynomially solvable.     

机床主轴的动刚性评估

本文提出了一种评估机床主轴的动刚性的一种新方法,此方法以机床主轴的固有频率为基础,在安装在机床主轴上的实验棒的半径方向上加振动脉冲,测出其固有频率,然后用固有频率算出主轴的刚度,另外对被测的机床又进行了主铣刀切削实验,得出了表面粗糙度与刚度的相关性.     

基于排队论的地铁车站自动售票机配置数量研究

自动售票机(TVM)自助售票是地铁车站主要的售票方式,TVM的服务效率直接影响了车站整个票务系统的高效性。以排队系统理论为基础,分析了乘客在TVM上购票时排队系统的基本特征,建立了M1/M2/c排队模型,并通过实例分析了车站在TVM数量配置上的合理性,给出了车站高峰时段及中长期客流增长情况下车站TVM配置建议。     

开设"数控机床故障诊断与维修"本科专业的思考

从数控机床可靠性、企业用工制度、高等职业教育等几个方面分析了我国数控机床产业落后的原因,提出了在普通高等学校开设数控机床故障诊断与维修本科专业的建议.