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51.
52.
合山电厂3个机组主厂房定向爆破拆除 总被引:1,自引:1,他引:0
介绍了广西合山电厂 1#~3# 机组主厂房定向爆破设计与施工.该工程不仅规模大、环境十分复杂、工期紧、难度高、风险性极强,最大特点是拆除发电设备与爆破同步进行施工. 相似文献
53.
54.
新型并条胶辊套筒的特点及运用 总被引:1,自引:1,他引:0
为了解决常规并条胶辊套筒存在的易发热、易漏油,芯轴易弯曲磨损以及保养、能耗等问题,介绍了新型免加油并条胶辊套筒的性能特点并以实际生产数据进行对比;说明实际使用该新型并条胶辊套筒综合效果好,具有省工省时、降低消耗、质量稳定、使用寿命长、总投资少等优点。 相似文献
55.
提出了在虚拟装配过程中零件与装配体碰撞干涉检测的一种方法。用投影轴算法检测出装配对象的碰撞,用坐标跟踪检测方法确定干涉余量值,并用连续包围盒对复杂和不规则的模型进行分割,通过这三种方法的配合使用,虚拟装配系统对干涉体进行了有效的、实时的、精确的检测。 相似文献
56.
Kaarina Aarnisalo Kaija Tallavaara Gun Wirtanen Riitta Maijala Laura Raaska 《Food Control》2006,17(12):1001-1011
The hygienic working practices of the maintenance personnel as well as the hygiene of the equipment in the food industry were investigated with questionnaires and microbial surveys. The protective clothing, washing of hands and tools as well as avoiding foreign bodies left on the production lines should be targeted when the hygienic working practices are developed for maintenance personnel. Based on the questionnaire to food processors, packaging machines, conveyers, dispensers, slicing and cooling machines were considered the most problematic pieces of equipment hygienically mainly because of poor hygienic design. In order to improve food safety, both the training of maintenance personnel in food hygiene and equipment design should be more emphasised. 相似文献
57.
采用分解法编写轴类零件程序,即将具有典型结构的轴分解成若干部分,把每一部分编成通用子程序,连同尺寸标注子程序、表面粗糙度子程序、剖面线子程序、尺寸公差及形位公差子程序等一并存贮在程序库中,需要时一一调用。 相似文献
58.
Gathercole Susan E.; Pickering Susan J.; Ambridge Benjamin; Wearing Hannah 《Canadian Metallurgical Quarterly》2004,40(2):177
The structure of working memory and its development across the childhood years were investigated in children 4-15 years of age. The children were given multiple assessments of each component of the A. D. Baddeley and G. Hitch (1974) working memory model. Broadly similar linear functions characterized performance on all measures as a function of age. From 6 years onward, a model consisting of 3 distinct but correlated factors corresponding to the working memory model provided a good fit to the data. The results indicate that the basic modular structure of working memory is present from 6 years of age and possibly earlier, with each component undergoing sizable expansion in functional capacity throughout the early and middle school years to adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
In a series of experiments, participants were required to keep track of 1 or 2 working memory (WM) objects, having to update their values in 80% of the trials. Updating cost, defined as the difference between update and non-update trials, was larger when 2 objects were involved compared with when there was only 1 object was involved. This finding was interpreted as evidence that the updating process encompasses both objects in WM, even though only 1 of them is actually updated. This feature of WM updating is limited to objects defined as "updateable," throughout the trial sequence. The results are explained by the need to reprogram the phonological loop when updating or the need for desynchronization followed by resynchronization of WM contents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Verhaeghen Paul; Cerella John; Basak Chandramallika 《Canadian Metallurgical Quarterly》2004,30(6):1322
Five individuals participated in an extensive practice study (10 1-hr sessions, 11,000 trials total) on a self-paced identity-judgment n-back task (n ranging from 1 to 5). Within Session 1, response time increased abruptly by about 300 ms in passing from n = 1 to n > 1, suggesting that the focus of attention can accommodate only a single item (H. Caravan, 1998; B. McElree, 2001). Within Session 10, response time was dramatically reduced and increased linearly with n for n ≤ 4, with a slope of about 30 ms. The data suggest that working memory consists of a focus of attention governed by a limited-capacity search, expandable through practice, and a content-addressable region outside the focus of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献