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31.
《Ergonomics》2012,55(4):331-343
Abstract

Different tabulation formats for currency conversion tables wore examined. It was found that most formats could be used equally well to make conversions bi-directionally, i.e. from A to B and from 13 to A. A fully redundant table, one that required no additional arithmetic operations, could be used more quickly than a schematic table, and in schematic tables it was more important to have each of the major units given directly rather than each of the minor units. A matrix, although fully redundant, was much more difficult to use than the corresponding table of lists. Many subjects clearly did not understand the principles of matrix format. Measures of incidental learning suggested that practice at using a table resulted in only slight knowledge of the content of the table, even though much of each table could be generated from a single rule  相似文献   
32.
环保高性能防腐涂料驱动未来市场   总被引:5,自引:0,他引:5  
介绍了防腐涂料的新品种和防腐体系的选择,指出了我国防腐涂料的发展趋势。  相似文献   
33.
For composites to compete in vehicle suspension applications, it is essential to control their failure by utilising their strength in principal direction instead of shear. This can be achieved efficiently by employing a new configuration instead of existing one. This study marries between an elliptical configuration and the woven roving composites.

In this paper, the influence of ellipticity ratio on performance of woven roving wrapped composite elliptical springs has been investigated both experimentally and numerically. A series of experiments was conducted for composite elliptical springs with ellipticity ratios (a/b) ranging from one to two. Typical failure histories of their failure mechanism are presented and discussed. In general, this study demonstrated that composites elliptical spring can be used for light and heavy trucks and meet the requirements, together with substantial weight saving. The results showed that the ellipticity ratio significantly influenced the spring rate and failure loads. Composite elliptic spring with ellipticity ratios of a/b 2.0 displayed the highest spring rate.  相似文献   

34.
利用炉膛断面温度场可视化监测系统、节能环保车、炉内三维数值模拟等先进的技术和设备对大机组调峰稳定性和运行方式优化进行试验和理论研究。  相似文献   
35.
AOD冶炼中,终点碳和终点温度的命中率是提高生产率和产品质量的关键。由初始温度,初始成分及补加合金量等原始数据,通过本模型可预报要达到目标终点碳所需要的脱碳时间以及相应的终点温度。本模型计算得到的终点碳与实际终点碳,在同等条件下,两者极为接近,可作为一般AOD冶炼中预报终点碳与脱碳时间关系之用。通过分级调整O2、Ar、N2气比例得到最佳脱碳效果,终点碳命中率可提高到98%以上,最高温度可以控制不超过1750℃,延长炉衬寿命。  相似文献   
36.
This study examined (a) the role of avoidance coping in prospectively generating both chronic and acute life stressors and (b) the stress-generating role of avoidance coping as a prospective link to future depressive symptoms. Participants were 1,211 late-middle-aged individuals (500 women and 711 men) assessed 3 times over a 10-year period. As predicted, baseline avoidance coping was prospectively associated with both more chronic and more acute life stressors 4 years later. Furthermore, as predicted, these intervening life stressors linked baseline avoidance coping and depressive symptoms 10 years later, controlling for the influence of initial depressive symptoms. These findings broaden knowledge about the stress-generation process and elucidate a key mechanism through which avoidance coping is linked to depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
37.
The paper contains a new algorithm for estimation of fatigue life in HCF regime under multiaxial random loading using spectral methods. Loading of Gaussian distribution and narrow‐ and broad‐band frequency spectra were assumed. Various characteristic states of multiaxial loading were considered. The equivalent stress history was determined with use of the failure criteria of multiaxial fatigue based on the critical plane. For determination of the critical plane position, the method of variance was applied. During simulation, the authors compared the results obtained by a spectral method in the frequency domain with those from the rain‐flow algorithm in the time domain. The paper also contains the results of fatigue tests for 18G2A structural steel subjected to bending and combined bending with torsion. The tests were performed in order to verify the proposed algorithms for determination of fatigue life. It has been shown that under multiaxial random loading results of fatigue life calculated according to the considered algorithms in frequency and time domains are well correlated with the results of experiments.  相似文献   
38.
针对大亚湾核电站实施18个月换料技术改造的特点,计算了大亚湾核电站在正常运行工况下以及各种设计基准事故工况下对周围环境的放射性后果。计算结果表明,大亚湾核电站实施18个月换料技术改造后,正常运行工况安全设施的性能满足GB6249-86的要求。  相似文献   
39.
智能楼宇综合管理系统的设计   总被引:7,自引:0,他引:7  
首先介绍了智能楼宇系统集成的问题,然后对智能楼宇综合管理系统的体系结构进行了设计分析了其特点,最后对其关键技术进行了研究。  相似文献   
40.
In this paper, a historical overview of significant attempts to get over the software crisis is presented. In particular, we trace the development of lifecycle models and information systems development methodologies during the last four decades. Finally, we explore the role of measurements and outline current and future works leading to process and product improvement.  相似文献   
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