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61.
《Ergonomics》2012,55(2):293-305
Abstract The literature on terminal control tasks and continuous tracking tasks suggests a possible model for tasks where the subject must guide a vehicle at his own speed along a course defined by a tolerance band. The model predicts a linear relationship between the average velocity and the width of the tolerance band. Throe experiments are described which simulate vehicle guidance by pencil-and-paper experiments for courses consisting of straight lines and circles. The predictions of the model were confirmed, suggesting that a general measure for the ease of control of a vehicle (or other controlled system) is possible using this technique. 相似文献
62.
《Ergonomics》2012,55(10):1515-1529
The study investigated the effects of using a lower body prototype exoskeleton (EXO) on static limits of stability and postural sway. Measurements were taken with participants, 10 US Army enlisted men, standing on a force platform. The men were tested with and without the EXO (15 kg) while carrying military loads of 20, 40 and 55 kg. Body lean to the left and right was significantly less and postural sway excursions and maximal range of movement were significantly reduced when the EXO was used. Hurst values indicated that body sway was less random over short-term time intervals and more random over long-term intervals with the EXO than without it. Feedback to the user's balance control mechanisms most likely was changed with the EXO. The reduced sway and relatively small changes in sway with increasing load weights suggest that the EXO structure may have functioned to provide a bracing effect on the body. 相似文献
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从天然气开发与利用,建设靖西管道的重大意义;全省上下同心协力,大打管道建设攻坚战;实行军民共建,既打经济仗,又打政治仗;指挥部实施有力领导,确保工程建设顺利进行等方面,在理论与实践的结合上进行了分析研究。 相似文献
66.
A. E. Avramenko 《Measurement Techniques》2006,49(6):585-591
A new method of generating pulsar time based on a coherent representation of a sequence of observed events is considered.
The properties of pulsar time compared with the traditional approach are analyzed.
__________
Translated from Izmeritel’naya Tekhnika, No. 6, pp. 39–44, June, 2006. 相似文献
67.
A. Wisitsoraat A. Tuantranont C. Thanachayanont V. Patthanasettakul P. Singjai 《Journal of Electroceramics》2006,17(1):45-49
Carbon nanotube (CNT) is a useful material for gas-sensing applications because of its high surface to volume ratio structure.
In this work, multi-wall CNTs are incorporated into tin oxide thin film by means of powder mixing and electron beam evaporation
and the enhancement of gas-sensing properties is presented. The CNTs were combined with SnO2powder with varying concentration in the range of 0.25–5% by weight and electron beam evaporated onto glass substrates. From
AFM and TEM characterization, CNT inclusion in SnO2thin film results in the production of circular cone protrusions of CNT clusters or single tube coated with SnO2layer. Experimental results indicate that the sensitivity to ethanol of SnO2thin film increases by the factors of 3 to 7, and the response time and recovery time were reduced by the factors of 2 or
more with CNT inclusion. However, if the CNT concentration is too high, the sensitivity is decreased. Moreover, the CNT doped
film can operate with good sensitivity and stability at a relatively low temperature of 250–300∘C. The improved gas-sensing properties should be attributed to the increasing of surface adsorption area of metal oxide produced
by CNT protrusion. 相似文献
68.
介绍了ZF12-145(L)三相共箱式气体绝缘金属封闭开关设备断路器的技术参数、性能、灭弧室的计算分析和主要特点. 相似文献
69.
神经网络在煤矿安全决策支持系统中的研究及应用 总被引:1,自引:0,他引:1
主要研究人工神经网络在煤矿安全决策支持系统中的应用。将BP网络用于瓦斯突出,解决了瓦斯突出判别困难、难以建立数学模型的难题,为煤矿瓦斯突出研究找到了一种新的建模和预测方法。 相似文献
70.