Chosen postures during specific sitting activities

This research study analysed the interaction between people's postures and activities while in semi-public/leisure situations and during transportation (journey by train). In addition, the use of small electronic devices received particular emphasis. Video recordings in German trains and photographs in Dutch semi-public spaces were analysed using a variation of Branton and Grayson's (An evaluation of train seats by observation of sitting behaviour. Ergonomics, 10 (1), (1967), 35–51) postural targeting forms and photos. The analysis suggests a significant relationship between most activities and the position of the head, trunk and arms during transportation situations. The relationship during public situations is less straightforward. Watching, talking/discussing and reading were the most observed activities for the transportation and leisure situations combined. Surprisingly, differences in head, trunk, arm and leg postures were not significant when using small electronic devices. Important issues not considered in this study include the duration of the activities, the gender and age of observed subjects and the influence of the time of day. These are interesting issues to consider and include for future research.

Statement of Relevance: This study shows what activities people choose to carry out and their related postures when not forced to a specific task (e.g. driving). The results of this study can be used for designing comfortable seating in the transportation industry (car passenger, train, bus and aircraft seats) and semi-public/leisure spaces.     

Computation of extreme eigenvalues in higher dimensions using block tensor train format

We consider approximate computation of several minimal eigenpairs of large Hermitian matrices which come from high-dimensional problems. We use the tensor train (TT) format for vectors and matrices to overcome the curse of dimensionality and make storage and computational cost feasible. We approximate several low-lying eigenvectors simultaneously in the block version of the TT format. The computation is done by the alternating minimization of the block Rayleigh quotient sequentially for all TT cores. The proposed method combines the advances of the density matrix renormalization group (DMRG) and the variational numerical renormalization group (vNRG) methods. We compare the performance of the proposed method with several versions of the DMRG codes, and show that it may be preferable for systems with large dimension and/or mode size, or when a large number of eigenstates is sought.     

无机化学实验中学生良好习惯的培养

针对来源于边远贫困地区的学生实际，在实验教学中，从实验前的预习、实验台的合理安排、观察记录实验现象、规范操作与仪表等六个方面，分析了无机化学实验中学生的常见问题，并从上述六个方面人手，尝试培养学生的良好实验习惯，收到了积极的效果。     

岳西县小水电开发思路与具体做法

文章介绍了岳西县小水电开发思路与具体做法。主要是认真编制规划、股份合作融资、优化设计方案、工程公开发包、实行目标管理等。     

Psychological work characteristics,psychological workload and associated psychological and cognitive requirements of train drivers

This study aimed to assess the psychological work characteristics and psychological workload of train drivers and to define the psychological and cognitive requirements of their work. A systematic literature search was performed, and expert interviews were conducted. The following work demands were specific to train drivers: high emotional and mental demands, small amount of autonomy and skill discretion. No evidence of a high emotional workload, a high mental workload or short-term stress reactivity was found. In general, the drivers' fatigue complaints and recovery needs after work were comparable to that of other workers. However, severe sleepiness and high need for recovery did affect a substantial proportion of train drivers. The ability to stay aware, to anticipate, to remain attentive and to cope with fatigue are psychological and cognitive skills that are required to adequately and safely perform the train drivers' job. Including these requirements in periodic assessments of train drivers is recommended.     

Passenger comfort on high-speed trains: effect of tunnel noise on the subjective assessment of pressure variations

When passing through a tunnel, aerodynamic effects on high-speed trains may impair passenger comfort. These variations in atmospheric pressure are accompanied by transient increases in sound pressure level. To date, it is unclear whether the latter influences the perceived discomfort associated with the variations in atmospheric pressure. In a pressure chamber of the DLR-Institute of Aerospace Medicine, 71 participants (M = 28.3 years ± 8.1 SD) rated randomised pressure changes during two conditions according to a crossover design. The pressure changes were presented together with tunnel noise such that the sound pressure level was transiently elevated by either +6 dB (low noise condition) or +12 dB (high noise condition) above background noise level (65 dB(A)). Data were combined with those of a recent study, in which identical pressure changes were presented without tunnel noise (Schwanitz et al., 2013, ‘Pressure Variations on a Train – Where is the Threshold to Railway Passenger Discomfort?’ Applied Ergonomics 44 (2): 200-209). Exposure-response relationships for the combined data set comprising all three noise conditions show that pressure discomfort increases with the magnitude and speed of the pressure changes but decreases with increasing tunnel noise.

Practitioner Summary: In a pressure chamber, we systematically examined how pressure discomfort, as it may be experienced by railway passengers, is affected by the presence of tunnel noise during pressure changes. It is shown that across three conditions (no noise, low noise (+6 dB), high noise (+12 dB)) pressure discomfort decreases with increasing tunnel noise.     

客车水栓压力在线监控系统的应用及推广

针对铁路客车上水栓的现状及特点,设计出一套客车水栓压力在线监测及故障自动切除系统,并分析了使用该系统的必要性,介绍了该系统可实现的功能,对该系统的关键技术及监控组态软件设计作了详细论述,以促进其推广应用。     

A health management algorithm for composite train carbody based on FEM/FBG hybrid method

In this study, a health management program for a composite train carbody was developed using the acquired strain distributions from fiber Bragg grating (FBG) sensor arrays. To determine appropriate locations for the FBG sensors, a finite element analysis (FEA) was executed. In this FEA, a FE model of the Korean tilting train (TTX) was used as a representative composite carbody train. The FEA results of various derailment situations and high speed operation on curved track were used as the database of each deformation case. In the last step, the health management program was produced using LabVIEW software. In this post-processing algorithm, the method of least squares was used to determine the difference between the FEA results and the acquired strains. This program shows the estimated deformations and plots of the acquired strains, as well as displaying an emergency indicator when necessary, all through post-processing of the strains. Finally, this FEM/FBG hybrid method was verified by several simulations using the reproductive sensor data.     

一种应用于列车信息画面实时重建的快速绘图方法

在许多视频应用中,画面重建是一个重要的课题。提出一种应用于列车信息实时分析重建系统的快速绘图方法使用双缓存技术在内存空间申请指定大小的位图,通过图形设备接口在该位图上进行图形绘制。绘图模块对基本绘图单元进行封装,各绘图元素单元具有相似的设置接口。采用了双缓冲技术避免闪烁,同时采用部分绘制方法,提高绘制速度。该绘图模块具有很好的可扩展性、实时性和灵活性。所提出的快速绘图方法在列车信息实时分析重建系统中得到很好的应用。     

32m双线简支箱梁在对开列车作用下梁体竖向动力响应规律研究

将列车、双线简支箱梁分别简化为二系悬挂多刚体体系和模态函数,推导车桥系统动力方程,建立并验证车桥相互作用模型,对双线简支箱梁在对开列车作用下梁体竖向动力响应规律进行研究。研究表明:对开列车作用下,桥梁动力响应与列车运行速度及入桥距离差密切相关;列车以共同速度对开时,可引起的梁体最大挠度动力系数与单线行车作用下基本一致,但梁体动力响应值约为单线行车引起的梁体动力响应值的2倍。