全国人体寄生虫分布调查——人体蠕虫感染的地理分布特点和规律

我国人体蠕虫感染有明显的地理分布特点和规律，如吸虫感染呈现随水系流域分布的规律，绦虫感染随地势三级阶梯而异，土源性线虫感染随温度带、干湿区域不同而呈不同的分布。     

Analysis of terrain effects on the interfacial force distribution at the hand and forearm during crutch gait

Forces transferred to the upper body during crutch use can lead to both short-term and long-term injuries, including joint pain, crutch palsy, and over-use injuries. While this force transmission has been studied in controlled laboratory settings, it is unclear how these forces are affected by irregular terrains commonly encountered during community ambulation. The purpose of this study was to determine the effects of walking speed and uneven terrain on the load magnitude, distribution, and rate of loading at the human-crutch contact surfaces. Our results show that the rates of loading were significantly increased with higher walking speeds and while negotiating certain irregular terrains, despite there being no apparent effect on the peak force transmission, suggesting load rate may be a more appropriate metric for assessing terrain effects on crutch gait. Furthermore, irrespective of the type of terrain and walking condition, the largest compressive forces were found to reside in the carpal-tunnel region of the hand, and may therefore be a primary contributor to carpal-tunnel injury.     

地形矢量信息的分块与LOD技术的研究与实现

矢量信息是地形建模当中非常重要的一类信息。作者研究了地形矢量信息分块与LOD的一些关键技术和实现方法,目的是为了正确地把矢量数据叠加到DEM上,并保证地形的渲染效率。作者以道路的矢量数据为例,研究了这两种技术的实现方法,并进行了多组试验,得到了满意的效果。     

基于Clipmap的大规模地形可视化技术研究

大面积地形渲染是创建高沉浸感室外场景的重要组成部分,其渲染效果直接影响到室外场景的真实度。大面积地形渲染具有两个关键技术,一是地形结构的生成,二是大面积影像图的渲染。本文采用Geometry clipmap结构构建地形的基本结构,地形结构跟随视点进行漫游,通过采样当前地形结构下各个顶点的高程值进行地形的渲染 同时通过C lipmap方法实现地形的纹理渲染。仿真实验表明文中方法具有较好的渲染效果和较高的实时性,可以满足视景仿真系统的需求。     

Quels tests de terrain pour le suivi de la performance athlétique en sport collectif ?

Introduction

To monitor athletic performance throughout a team-sport season, strength and conditioning coaches are used to program various field tests that evaluate physiological variables predictive of performance in their activity. Nevertheless, performing all these field tests is time consuming and not well appropriated for frequent monitoring.

Synthesis of the facts

The present study investigated whether a single test can be used as a surrogate of overall team athletic performance.

Conclusion

It appears that the 30-15 Intermittent Fitness Test and a repeated sprint ability test, but not explosive power of lower limb or sprinting tests, are sensitive enough to differentiate different performance levels throughout the season.     

From the Cover: Sensitive dependence of the motion of a legged robot on granular media

Legged locomotion on flowing ground (e.g., granular media) is unlike locomotion on hard ground because feet experience both solid- and fluid-like forces during surface penetration. Recent bioinspired legged robots display speed relative to body size on hard ground comparable with high-performing organisms like cockroaches but suffer significant performance loss on flowing materials like sand. In laboratory experiments, we study the performance (speed) of a small (2.3 kg) 6-legged robot, SandBot, as it runs on a bed of granular media (1-mm poppy seeds). For an alternating tripod gait on the granular bed, standard gait control parameters achieve speeds at best 2 orders of magnitude smaller than the 2 body lengths/s (≈60 cm/s) for motion on hard ground. However, empirical adjustment of these control parameters away from the hard ground settings restores good performance, yielding top speeds of 30 cm/s. Robot speed depends sensitively on the packing fraction and the limb frequency ω, and a dramatic transition from rotary walking to slow swimming occurs when becomes small enough and/or ω large enough. We propose a kinematic model of the rotary walking mode based on generic features of penetration and slip of a curved limb in granular media. The model captures the dependence of robot speed on limb frequency and the transition between walking and swimming modes but highlights the need for a deeper understanding of the physics of granular media.     

一种基于多门限二进制编码的多光谱图像分类新方法

不同类型的地物具有不同的反射光谱 ,在多维光谱空间中构成不同的特征向量 ,这便是遥感多光谱图象分析与识别的物理依据。传统方法中有基于单个象元波段亮度的、空间纹理的、变换空间的多光谱图象特征提取与分析方法 ,但这些方法并没有直接描述地物的最本质特征———反射光谱曲线 ,从上个世纪 80年代开始 ,当二进制编码的方法提出并在多光谱匹配识别中获得成功应用后 ,多光谱图象分析处理便可以在这种特征提取的基础上 ,研究新的方法。本文提出一种基于光谱形状描述的多门限的二进制编码分类方法 ,并给出了图象实验的结果。     

沿长江流域不同地势四省份老年人病种的地域特征

[目的]研究长江流域不同地势阶梯的四省份老年人的病种与地域间的关系,为有针对性地防病、治病、健康教育提供依据。[方法]利用青、川、鄂、苏四省国民体质监测报告的统计数据,采用数理分析法、类比分析法,由西向东对处于长江流域不同地势四省份老年人的肿瘤、心脑血管疾病、呼吸系统疾病、意外事故、消化系统疾病、内分泌系统疾病、泌尿生殖系统疾病、高血压、糖尿病、其他疾病等病种进行了对比研究。[结果]心脑血管疾病、糖尿病分别与地域呈线性相关;肿瘤病与内分泌系统疾病患者的住院率与地域所处阶梯之间呈二次曲线关系;泌尿生殖系统疾病与地域所处阶梯之间的关系不大;其他疾病住院与地域所处阶梯之间几乎没有关系。[结论]老年人的病种受海拔、气候、经济、生活习惯、饮食等因素的影响,四省老年人的住院病种存在着不同程度的差异,表现出相对独特的地域特征。