A review of: “Introduction A La Psychophysiologie Du Travail (Introduction to the Psychophysiology of Work)”, by ROBERT FLORU and JEAN-CLAUDE CNOCKAERT,Presses Universitaires De Nancy (1991). pp. vi + 233, FF 120, ISBN 2-86480-550-2.

Workers in physically demanding occupations (PDOs) are frequently subjected to physical selection tests. To avoid legal ramifications, workplaces must be able to show that any personnel selection procedures reflect the inherent requirements of the job. A job task analysis (JTA) is fundamental in determining the work tasks required for employees. To date, there are no published instructions guiding PDO researchers on how to conduct job task analyses. Job task analysis research for non-PDOs offers some insight into the expected reliability and validity of data obtained on the most prevalent task domains in job analysis (importance, frequency, time spent and difficulty). This review critiques such research, and the existing published material on JTA of PDOs, and provides recommendations for future research and practice.

Practitioner Summary: There are no published guidelines for physically demanding occupation (PDO) researchers conducting job task analysis (JTA). Given the legal consequences of improperly conducted JTA, scientifically valid instructions for JTA practitioners are required. This review critiques existing research which analyses reliabilities of JTA data, and provides guidelines for PDO researchers conducting JTA.     

Validity and reliability of the Spineangel® lumbo-pelvic postural monitor

Objective: to determine the reliability and the concurrent validity of the Spineangel^® lumbo-pelvic postural monitoring device. Methods: the dynamic lumbo-pelvic posture of 25 participants was simultaneously monitored by the Spineangel^® and Fastrak^TM devices. Participants performed six different functional tasks in random order. Within-task, within-session and between-day intraclass correlation coefficients (ICC(3,1), ICC(3,5), ICC(2,5), respectively) reliability were calculated for Spineangel^® measurements. Concurrent validity of the Spineangel^® was assessed by means of a Bland and Altman plot and by means of Pearson's correlation coefficient and paired t-test. Results: within-task, within-session and between-day ICC for the Spineangel^® were found to be excellent (>0.93). The Spineangel^® and Fastrak^TM pelvic measurements were found to have a good correlation (R = 0.77). Conclusion: the Spineangel^® is a reliable and valid device for monitoring general lumbo-pelvic movements when clipped on the belt or waistband of workers' clothing during various occupational activities.

Practitioner summary: The Spineangel^® can be used for assessing lumbo-pelvic posture during work or daily-life activities. This device was found to provide reliable and valid measurements for lumbo-pelvic movements. Further research is required to determine whether the use of this device is clinically relevant for patients presenting with low back pain.     

利用元素俘获测井评价致密砂岩岩性及有效性

地层孔隙度的准确计算是储层综合评价与预测、储量计算、产能评估的基础。矿物含量与岩石骨架密度紧密相关,因此可以根据元素俘获谱测井所得到矿物成份及含量来计算岩石骨架值、识别岩性,并结合密度测井重新计算储层的孔隙度,进而判别裂缝的有效性。通过在大北克深地区孔隙度计算、裂缝有效性评价中的应用,该方法获得了较好的效果。     

模糊C-均值聚类算法改进研究

通过对模糊C-均值聚类算法的研究,用遗传算法的相关知识对其进行优化与改进.并使用著名的IRIS数据集分别对传统的模糊C-均值聚类算法和用遗传算法改进后的模糊C-均值聚类算法进行测试、比较.实验结果表明,用遗传算法改进后的模糊C-均值聚类算法比传统的模糊C-均值聚类算法更加准确、高效.这将为以后的聚类分析研究工作提供一定的帮助.     

基于减法聚类与聚类有效性评判的FCM聚类

提出了一种基于减法聚类和聚类有效性评判的FCM聚类算法,依靠减法聚类来确定聚类数目的上限,并且在搜索最佳聚类数copt时,不需要进行重复的初始化工作,从而提高聚类的效率.     

聚类有效性研究

在对现有各种聚类有效性函数进行深入分析的基础上，提出了一种改进的聚类有效性函数，通过引入模拟退火机制，以获得最佳聚类结果。与其他经典的聚类有效性函数相比，改进后的聚类有效性函数一方面避免了单调性，另一方面又与数据集合本身的特征相关。仿真实验表明了其有效性。     

论产品设计中的"形"

设计始于形,形是材料在空间的一种排列方式,如同语言中的句法和语法。形首先存在于人的思维中,并通过大脑对现实的经验进行概括和分类。产品设计的过程就是根据你的形式概念进行的,产品是形式的具体体现和表达。解读形对我们产品设计具有非常实际的意义。     

基于隐Markov模型的复杂仿真系统

根据复杂仿真系统具备随机性、严格时序逻辑性等工程实际特点,提出一种以隐Markov模型（HMM）为基础,利用多元统计理论定量分析复杂仿真系统运行有效性的评价方法.在引入状态观测向量矩阵的基础上,详细介绍了量化描述仿真剧情、复杂仿真系统运行状态的HMM的建立方法,给出了复杂仿真系统运行有效性评价准则,并针对评价过程中的关键算法进行了深入研究.     

多尺度PCA在传感器故障诊断中的应用研究

A multiscale principal component analysis method is proposed for sensor fault detection and identification. After decomposition of sensor signal by wavelet transform, the coarse-scale coef-ficients from the sensors with strong correlation are employed to establish the principal component analysis model. A moving window is designed to monitor data from each sensor using the model.For the purpose of sensor fault detection and identification, the data in the window is decomposed with wavelet transform to acquire the coarse-scale coefficients firstly, and the square prediction error is used to detect the failure. Then the sensor validity index is introduced to identify faulty sensor,which provides a quantitative identifying index rather than qualitative contrast given by the approach with contribution. Finally, the applicability and effectiveness of the proposed method is illustrated by sensors of industrial boiler.     

听说领先英语教学新模式的探讨

本文基于对TEM4听力测试的信度、效度研究,提出了重点旨在提高学生听说能力的大学英语教学改革设想,并进行了初步探讨和实践。