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171.
先进的报警系统是核电厂先进的控制室中重要的系统之一,阐述了核电厂先进的报警系统的重要性、功能和特点,并且比较详细地论述了报警信号的处理方法和显示方式。 相似文献
172.
激光焊接超细基胎体金刚石薄壁钻 总被引:6,自引:1,他引:5
采用激光焊接超细预合金粉胎体,开发了新的薄壁钻产品,通过对与现有的产品工艺、性能测试以及实际使用分析对比,结果表明:激光焊接与普通钎焊相比结合强度提高2-3倍,克服了胎体脱落问题,胎体耐磨性提高了50%-120%,其中轴向磨损速率提高1.2倍;钻削速度提高30.4%,工矿适应性增加,使用寿命提高25%-108%。 相似文献
173.
用精确饲喂技术评价了 3个品种的中国双低油菜和 1个加拿大卡诺拉的脱脂种籽和商品饼粕的能量和氨基酸的有效性。结果表明 ,4个脱脂种籽的氮校正真代谢能和氨基酸真消化率没有差异 (P >0 .0 5 ) ;而 4个商品饼粕的脱脂样品的氮校正真代谢能和氨基酸真消化率有极显著或显著差异。研究结果证实 ,不适当的加工方式不仅降低了氨基酸的有效性 ,而且影响家禽对能量的利用效率。 相似文献
174.
Deterministic chaos theory offers useful quantitative tools to characterize the non-linear dynamic behavior of a fluidized bed and the developed complexity theory presents a new approach to evaluate finite sequences. In this paper,the non-linear,hydrodynamic behavior of the pressure flutuation signals in a reactor was discussed by chaos parameters and complexity measures.Coherent results were achieved by our multi-scale analysis,which further exposed the behavior in a gas-solid two-phase system. 相似文献
175.
A study of dislocation configurations in superconducting oxide BiSrCaCuO has been made by transmission electron microscopy. Evidence was found for the presence of dislocation pairs composed of two parallel single dislocations holding together with the same Burgers vectors. The pair can further dissociate into partials, giving rise to a four-fold ribbon. Networks consisting of dislocation pairs were also observed. These phenomena are attributed to the possible ordering of strontium and calcium ions and the existence of some oxygen sheet of the Aurivillius type in the oxide crystal. Schemes to illustrate the configurations are suggested and discussed. 相似文献
176.
177.
通过有限元的方法,分析了T型薄壁管节点受平面内弯矩作用下的疲劳行为,得到了应力最大值的位置和拟合出用于预测T型薄壁管节点受平面内弯矩作用下的应力集中系数的参数公式。 相似文献
178.
BACKGROUND: We report experience with patients presenting with a specific combination of symptoms: unilateral sciatica, unilateral sensibility loss in the dermatomes S1 to S5 (hemi-saddle) and subjective micturation problems secondary to ruptured lumbar disc. Because of its similarities with a cauda equina syndrome, this combination of symptoms was thought to be a unilateral cauda equina syndrome and it was called hemi-cauda equina syndrome. Consequently, it was treated as an emergency. METHODS: Ten patients were evaluated. They compromised 2.3% of all patients undergoing lumbar discectomy. RESULTS: Outcome is good with only 10% persisting minor neurologic deficit (sensibility loss in dermatomes S3 to S5). With the exception of urinary retention or incontinence, duration of symptoms and signs does not seem to influence outcome. Comparing signs, symptoms and radiographic findings with those of a cauda equina syndrome which were recently and thoroughly studied, they were found to be more severe in cases of cauda equina syndrome. Especially, the good outcome, (apparently unrelated to the duration of symptoms in cases of hemi-cauda equina syndrome) contrasted with the treatment results of cauda equina syndrome. CONCLUSIONS: We defined the hemi-cauda equina syndrome from ruptured disc as a combination of unilateral leg pain, unilateral sensibility loss in dermatomes S1 to S5 and sphincter paralysis (proven urinary retention or incontinence). Motor deficit is not necessarily present. Emergency surgery is warranted. Patients presenting with micturation complaints other than urinary retention or incontinence do not suffer from a hemi-cauda equina syndrome. 相似文献
179.
基于自组织神经网络的实时统计特征抽取方法 总被引:3,自引:0,他引:3
应用人工神经网络讨论统计了特征抽取的原理,提出了相应的抽取方法。该方法具有实时性,容错性,高数据压缩率和良好的特征分辨率。通过计算机仿真和桥梁索力状态的实例计算分析证实了该技术具有广泛的应用价值。 相似文献
180.
The copolymer from D ,L -lactide and poly(tetramethyene ether glycol) (PTMG) was prepared in bulk with an isotributyl aluminum–water–phosphoric acid complex catalyst as the initiator and characterized by H-NMR, GPC, and DSC. The effects of the temperature and the amount of PTMG on the polymerization rate and the molecular weight of copolymers were studied. The behavior of the degradation and delivery rate of Levonorgestrel microspheres in vitro was observed. The results show that the degradation and the delivery rate can be controlled by adjusting the molar rate of hydrophilic and hydrophobic segments of the copolymer © 1995 John Wiley & Sons, Inc. 相似文献