Determining optimal cadence for an individual road cyclist from field data

The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it.     

Effects of load mass carried in a backpack upon respiratory muscle fatigue

Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h^?1 wearing a backpack of either 0 (LC₀), 10 (LC₁₀), 15 (LC₁₅) or 20?kg (LC₂₀). Inspiratory (P_Imax) and expiratory (P_Emax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean P_Imax and P_Emax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters.     

分析法、综合法在精读课中的运用

精读课既要分析法,也要综合法。两种方法同时运用,才能做到点面结合,避免学习孤立的语言现象,这样才能更深刻地理解课文。     

《训诂学初稿》引文辨误（下）

本文指出了《训诂学初稿》一书中存在的句读标点误、格式误、打印误、语序误、综合错误等五类引文错误，并对它们进行了辨正。     

初中英语教学中社会文化背景的意识提升

英语作为世界最通用的语言 ,其交际功能愈显重要。但语言离不开其文化背景 ,而不同民族文化又具有差异性。所以英语教师必须加强英语教学中的社会文化背景教学 ,使学生通过文化语境掌握文化能力 ,熟悉交际方式 ,保证交际成功。     

谈谈古今字与通假字的区分问题--兼与中学语文编写组商榷

古今字与通假字是两种不同的用字现象，但由于中学语文教材把二者混为一谈，不加区分，所以长期影响人们的视听，特别是对大学古代汉语课的教学造成相当的困难。     

矿井多风机风压优化计算机调节系统设计

经过对多风机通风网络分析,利用现有的VNETPC模拟程序,建立了多风机风压优化计算机调节系统.该系统允许计算机自动调整多风机风压,直到各用风地点获得最佳可接受的风量分配为止.     

证明不等式的几种特殊方法

从不等式的结构和特点出发,在已学过的知识的基础上进行广泛的联想,构造一个与不等式相关的数学模型,实现问题的转化,从而使不等式得到证明。本文探讨如何用构造法和柯西不等式法两种特殊方法来证明不等式。     

英语缩略语浅析

用缩略法创造新词，是现代英语的一种构词方法。常见的英语缩略词构词法有截短法、首字母缩略法、拼缀法、首字母拼音法等。以这种方法构成的新词具有经济高效、醒目、易记等特点，被汉语越来越多地直接借用。因此，了解常用缩略语的原形，将有助于我们更好地理解其中所要表达的思想。     

一种高速网络下分布式入侵检测体系结构的设计与实现

随着网络速度不断提高和规模的快速扩展,对入侵检测系统的模型、结构和实现技术提出了新的需求。在深入分析和讨论现有入侵检测模型和技术优缺点的基础上,针对高速网络的特点,本文提出了一种层次可变的树状分布式入侵检测体系结构。该结构可以根据网络规模的变化动态地进行配置,各节点的增加和删除采取注册和注销的方式,而且树状结构中的每一个独立节点都可视为一个完整的入侵检测系统。利用动态负载均衡与基于协议分析的多模式匹配技术对其进行实现。