Application of wearable sensors for human gait analysis using fuzzy computational algorithm

The authors have developed and tested a wearable inertial sensor system for the acquisition of gait features. The sensors were placed on anatomical segments of the lower limb: foot, shank, thigh, and hip, and the motion data were then captured in conjunction with 3D ground reaction forces (GRFs). The method of relational matrix was applied to develop a rule-based system, an intelligent fuzzy computational algorithm. The rule-based system provides a feature matrix model representing the strength of association or interaction amongst the elements of the gait functions (limb-segments accelerations and GRFs) throughout the gait cycle. A comparison between the reference rule-based data and an input test data was evaluated using a fuzzy similarity algorithm. This system was tested and evaluated using two subject groups: 10 healthy subjects were recruited to establish the reference fuzzy rule-base, and 4 relapsing remitting multiple sclerosis subjects were used as an input test data; and the grade of similarity between them was evaluated. This similarity provides a quantitative assessment of mobility state of the impaired subject. This algorithmic tool may be helpful to the clinician in the identification of pathological gait impairments, prescribe treatment, and assess the improvements in response to therapeutic intervention.     

S-states of helium-like ions

A simple Mathematica (version 7) code for computing S-state energies and wave functions of two-electron (helium-like) ions is presented. The elegant technique derived from the classical papers of Pekeris (1958, 1959, 1962, 1965, 1971) [1], [2] and [3] is applied. The basis functions are composed of the Laguerre functions. The method is based on the perimetric coordinates and specific properties of the Laguerre polynomials. Direct solution of the generalized eigenvalues and eigenvectors problem is used, distinct from the Pekeris works. No special subroutines were used, only built-in objects supported by Mathematica. The accuracy of the results and computation times depend on the basis size. The ground state and the lowest triplet state energies can be computed with a precision of 12 and 14 significant figures, respectively. The accuracy of the higher excited states calculations is slightly worse. The resultant wave functions have a simple analytical form, that enables calculation of expectation values for arbitrary physical operators without any difficulties. Only three natural parameters are required in the input.The above Mathematica code is simpler than the earlier version (Liverts and Barnea, 2010 [4]). At the same time, it is faster and more accurate.

Program summary

Program title: TwoElAtomSL(SH)Catalogue identifier: AEHY_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHY_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 11 434No. of bytes in distributed program, including test data, etc.: 540 063Distribution format: tar.gzProgramming language: Mathematica 7.0Computer: Any PCOperating system: Any which supports Mathematica; tested under Microsoft Windows XP and Linux SUSE 11.0RAM:?¹⁰⁹ bytesClassification: 2.1, 2.2, 2.7, 2.9Nature of problem: The Schrödinger equation for atoms (ions) with more than one electron has not been solved analytically. Approximate methods must be applied in order to obtain the wave functions or another physical attributes from quantum mechanical calculations.Solution method: The S-wave function is expanded into a triple set of basis functions which are composed of the exponentials combined with the Laguerre polynomials in the perimetric coordinates. Using specific properties of the Laguerre polynomials, solution of the two-electron Schrödinger equation reduces to solving the generalized eigenvalues and eigenvector problem for the proper Hamiltonian. The unknown exponential parameter is determined by means of minimization of the corresponding eigenvalue (energy).Restrictions: First, the too large length of expansion (basis size) takes the too large computation time and operative memory giving no perceptible improvement in accuracy. Second, the number of shells Ω in the wave function expansion enables one to calculate the excited nS-states up to n=Ω+1 inclusive.Running time: 2–60 minutes (depends on basis size and computer speed).     

低空飞艇地面监控系统设计与实现

以某低空实验飞艇项目为背景,基于LabWindows/CVI设计并实现了低空飞艇地面监控系统的上层软件,对底层串口通信程序、飞艇遥控操纵杆程序以及飞艇实时状态数据库连接等几个关键问题进行了详细设计。该地面监控系统经过长期运行表明该监控软件运行稳定,功能完备实用,具有较高的工程应用价值。     

Sulfate attack on alkali-activated slag concrete

This paper presents an investigation into durability of alkali-activated slag (AAS) concrete in sulfate environment. Two tests were used to determine resistance of AAS concrete to sulfate attack. These tests involved immersion in 5% magnesium sulfate and 5% sodium sulfate solutions. The main parameters studied were evolution of compressive strength, products of degradation, and microstructural changes. After 12 months of exposure to the sodium sulfate solution, the strength decrease was up to 17% for AAS concrete and up to 25% for ordinary Portland cement (OPC) concrete. After the same period of exposure to the magnesium sulfate solution, the compressive strength decrease was more substantial, up to 37% for OPC and 23% for AAS. The main products of degradation were ettringite and gypsum in the case of Portland cement and gypsum in AAS. OPC samples had significant expansion, cracking, and loss of concrete, while AAS samples were not expanded but cracked in the test. During experiments with the sodium sulfate solution, some increase in strength of AAS concrete was recorded, likely due to continuing hydration.     

小型无人直升机地面控制站设计与实现

通过分析小型无人直升机对地面控制站的需求,介绍地面控制站的结构和功能,分析开发地面控制站涉及的关键技术和解决方案,控制站采用基于面向对象的VC++开发环境和嵌入式Matlab混合编程技术。通过在某小型无人直升机飞行实验中的应用,证明该系统具有实时性强、稳定性好、人机界面友好、可扩展能力强等优点。     

地质雷达在水电站坝基工程中的应用研究

岩溶地区水电站工程建设中对坝基岩体完整程度要求较高,为了探明坝基岩体中是否存在溶洞、溶隙和破碎带等不良地质体,应用地质雷达较准确地判断出了坝基下不良地质体的走向和规模,取得了良好的效果,为处理岩溶地质问题和工程安全施工提供了依据.     

遥感技术在大同矿区地质灾害调查中的应用

煤矿是我国国民经济的支柱产业之一。而采矿引起的一系列地质灾害不仅威胁矿区安全,而且影响和制约着经济的发展,从而引发一系列社会问题和矛盾。大同地区最主要的矿山地质灾害是以煤矿开采引发的地面塌陷。而遥感作为信息获取的快速、有效的工具,具有宏观性好、更新周期快、人为因素干扰小等优点,可以直接为地质灾害监测的决策者提供丰富的客观数据,还可以通过推理、演绎和归纳等科学方法,提炼出需要的科学数据,这样不仅丰富了地质灾害监测决策的技术手段,还大大提高了决策的效率。     

探地雷达在水利工程安全检测中的应用

以陕西神木采兔沟水库工程为实例,对探地雷达的工作原理及实际应用进行了介绍。结合采兔沟泄洪洞洞身的质量检测对具体的测线布置、探测方法及参数选择进行了阐述,在探测中,针对泄洪洞具体形状,在不同部位共布置了17条测线,经对检测结果分析,发现导流泄洪洞底板下方虽存在疏松区域,但不存在空洞,其他部位亦无大的缺陷,不影响安全运行。     

缅甸敏达水电站厂房设计

结合缅甸敏达水电站地形地质条件,从厂址比选、开关站型式比选和厂房布置等几个方面介绍了该水电站厂房设计的基本思路及设计要点。