A comparison of methods to determine bilateral asymmetries in vertical leg stiffness

Whilst the measurement and quantification of vertical leg stiffness (K_vert) asymmetry is of important practical relevance to athletic performance, literature investigating bilateral asymmetry in K_vert is limited. Moreover, how the type of task used to assess K_vert may affect the expression of asymmetry has not been properly determined. Twelve healthy males performed three types of performance tasks on a dual force plate system to determine K_vert asymmetries; the tasks were (a) bilateral hopping, (b) bilateral drop jumping and (c) unilateral drop jumping. Across all the three methods, K_vert was significantly different between compliant and stiff limbs (P < 0.001) with a significant interaction effect between limb and method (P = 0.005). Differences in K_vert between compliant and stiff limbs were ?5.3% (P < 0.001), ?21.8% (P = 0.007) and ?15.1% (P < 0.001) for the bilateral hopping, bilateral drop jumping and unilateral drop jumping methods, respectively. All the three methods were able to detect significant differences between compliant and stiff limbs, and could be used as a diagnostic tool to assess K_vert asymmetry. Drop jumping tasks detected larger K_vert asymmetries than hopping, suggesting that asymmetries may be expressed to a greater extent in acyclic, maximal performance tasks.     

相平衡与CO2在水中的扩散速率--CO2排水集气法

根据相平衡等的有关计算可知，常压下CO2溶于水的过程为物理吸收，CO2的饱和水溶液为稀溶液，而且溶液里碳酸的生成和电离可以忽略不计。CO2在水中的扩散系数非常小，其数量级为10^-5cm^2／s，在CO2排水集气法操作中，CO2气体不被水吸收。     

真空-堆载联合预压法加固软土地基

真空-堆载联合预压法是加固饱和软粘土的理想方法，通过试验，观测路基的表面沉降和水平位移，说明真空预压能使地基产生较大的沉降速率，同时提高路基的稳定性，侧向位移量和位移速率与荷载大小的相关性比较明显。     

基于Matlab的散斑干涉分析及应用

介绍了电子散斑干涉测量离面位移的原理和利用Matlab得到散斑“相关条纹”的方法,并利用电子散斑干涉法测得了玻璃在一定压力下的形变量.实验结果表明,将散斑干涉场中的固定部分作为0级条纹位置,可以有效地对物体的形变进行定量分析.     

佛教思想对《南柯记》创作的影响

汤显祖的＂临川四梦＂奠定了他在戏剧史上的地位,其中的《南柯记》,始终笼罩着浓厚的宗教气氛,在佛教的大框架下杂有比较浓厚的＂万事无常＂、＂诸色皆空＂、＂人生如梦＂的虚无主义思想和消极的出世思想。     

储油罐的变位识别与罐容表标定

研究了储油罐的变位识别与罐容表标定的问题.针对问题一,利用求体积的定积分法,求出了罐体在无变位与纵向变位两种情况下分别关于油位高度及纵向倾斜角的体积表达式,得出了无变位和纵向倾斜角为α=4.1°两种情况下的罐容表标定值.针对问题二,利用非线性最小二乘法得到两个偏转角,并制定出罐体变位后油位高度的罐容表标定值.     

简化D值法框架结构的侧移估算

通过实例说明了简化D值法对框架结构进行的侧移估算,为结构的初步设计提供方便.     

目击时间的深渊——《野蔷薇》及其他

《野蔷薇》颇富思辨色彩,比较自觉集中地表达了那一时期茅盾的"时间哲学",同时比较早地提出了反思现代性这一历史课题.迁移与错位、直线与循环、潜隐与彰显等诸时间形态的对立与连接构成了文本的内在的叙事理路,也彰显了作者时间意识的深厚蕴含.     

长枞水电大坝的热弹性与渗漏分析

This paper deals with the temperature and displacement fields of the top mid-block of south transition at Long Spruce Generating Station, in the North of Manitoba, Canada. According to the experimental results of Manitoba Hydro in the past two years, the top mid-block is assumed to be a rectangular one that has two supposed temperature distributions at its boundary sides. Then, the temperature fields for the top mid-block are obtained from the analytical solutions by separation of variables. By using the analytical solution of temperature field, the displacement behavior of the top block in various temperature fields is discussed in details. The numerical results are given to show the causes of the leakage between the top mid-block and the dam. Finally, the repair methods for leakage are discussed for practical leaking repair and its engineering applications.     

Estimating fat-free mass in elite-level male rowers: a four-compartment model validation of laboratory and field methods

The purpose of this study was to investigate the accuracy of fat-free mass (FFM) estimates from two-compartment (2C) models including air displacement plethysmography (ADP), ultrasound (US), near-infrared interactance (NIR), and the Jackson and Pollock skinfold equation (SKF) against a criterion four-compartment (4C) model in elite male rowers. METHODS: Twenty-three elite-level male rowers (mean± SD; age 24.6 ± 2.2 years; stature: 191.4 ± 7.2 cm; mass: 87.2 ± 11.2 kg) participated in this investigation. All body composition assessments were performed on the same day in random order, except for hydrostatic weighing (HW), which was measured last. FFM was evaluated using a 4C model, which included total body water from bioimpedance spectroscopy, body volume from HW, and total body bone mineral via dual-energy X-ray absorptiometry. The major findings of the study were that the 2C models evaluated overestimated FFM and should be considered with caution for the assessment of FFM in elite male rowers. Future studies should use multiple-compartment models, with measurement of TBW and bone mineral content, for the estimation of FFM.