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配置抗冲切钢筋的混凝土异形柱-板柱连接试验研究 总被引:4,自引:0,他引:4
在9个柱截面为三种典型异形柱(十字形、T形和L形) -板柱连接未配置抗冲切钢筋时的冲切特性试验基础上,以十字形柱-板柱连接为代表,通过三个配置抗冲切钢筋试件与三个未配抗冲切钢筋试件的对比试验,研究了异形柱-板柱连接配置抗冲切钢筋后的冲切特性,同时将锚栓和箍筋的抗冲切性能进行了对比。试验结果表明,抗冲切钢筋可以有效地提高板的受冲切承载力和延性,在改善延性方面,锚栓比箍筋更有效。另外,将国外几个主要规范ACI3 18、BS8110及MC90 ,关于对非矩形荷载面冲切临界截面周长的规定进行了比较,从试验结果看,ACI3 18规范的取法更合理。 相似文献
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Carl M. Kjellstrand Christopher R. Blagg 《Hemodialysis international. International Symposium on Home Hemodialysis》2003,7(1):67-71
The cumulative survival of Japanese hemodialysis patients is more than 2.5 times better than that of dialysis patients in the United States (U.S.). The difference is particularly pronounced in older patients, being 4 times better in patients over the age of 50 years. The mortality in U.S. patients has increased from 10 to 25% over the last three decades, but has remained stable at around 10% in Japan.
There is no obvious difference in patient selection. The Japanese accept almost as high a proportion of diabetic patients as does the United States, and the mean age of incident patients is higher in Japan.
Renal transplantation, virtually absent in Japan, should increase mortality in U.S. dialysis patients by removing patients with the highest probability of survival, but even if one adds surviving transplant patients and studies prevalent populations, the survival rate is much better in Japan. Genetic factors are unlikely to explain differences in mortality, as older Americans live much longer than older Japanese.
We speculate that the difference lies in the practice of dialysis. Patients in the United States are generally treated by much faster and shorter dialysis than in Japan. This puts a severe burden on the cardiovascular system of older patients, leading to the poorer survival rate. Japanese physicians also appear to be better trained in dialysis and to spend more time with their patients. The nursing shortage in the United States may also contribute to the increased mortality. Whatever the explanations, the U.S. dialysis community must work to equal and, hopefully, surpass the now superior survival of Japanese dialysis patients. 相似文献
There is no obvious difference in patient selection. The Japanese accept almost as high a proportion of diabetic patients as does the United States, and the mean age of incident patients is higher in Japan.
Renal transplantation, virtually absent in Japan, should increase mortality in U.S. dialysis patients by removing patients with the highest probability of survival, but even if one adds surviving transplant patients and studies prevalent populations, the survival rate is much better in Japan. Genetic factors are unlikely to explain differences in mortality, as older Americans live much longer than older Japanese.
We speculate that the difference lies in the practice of dialysis. Patients in the United States are generally treated by much faster and shorter dialysis than in Japan. This puts a severe burden on the cardiovascular system of older patients, leading to the poorer survival rate. Japanese physicians also appear to be better trained in dialysis and to spend more time with their patients. The nursing shortage in the United States may also contribute to the increased mortality. Whatever the explanations, the U.S. dialysis community must work to equal and, hopefully, surpass the now superior survival of Japanese dialysis patients. 相似文献
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Exposure to turbulence, an environmental stimulus, produces behavioral adaptation in the Aplysia siphon-withdrawal response (SWR). The authors show that the duration and spatial extent of turbulence influence adaptation recovery. In terms of duration, recovery in whole animals and reduced preparations (tail, siphon, and CNS) was more rapid after longer exposures to turbulence (10 min) than after briefer exposures (10 s-5 min). In terms of spatial extent, recovery in reduced preparations was more rapid after diffuse turbulence (tail and siphon together) compared with focal turbulence (siphon alone). Furthermore, spatial extent and duration interact: Duration regulates recovery only when turbulence is diffuse. Results suggest that SWR adaptation reflects a composite of cellular processes, including short-term synaptic enhancement in L30 inhibitory interneurons. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Relative merits of interval and entrainment conceptions of the internal clock were assessed within a common theoretical framework by 4 time-judgment experiments. The timing of tone onsets marking the beginning and ending of standard and comparison time intervals relative to a context rhythm were manipulated: onsets were on time, early, or late relative to the implied rhythm, and 2 distinct accuracy patterns emerged. A quadratic ending profile indicated best performance when the standard ended on time and worst performance when it was early or late, whereas a flat beginning profile (Experiments 1-3) indicated uniform performance for the 3 expectancy conditions. Only in Experiment 4, in which deviations from expected onset times were large, did significant effects of beginning times appear in time-discrimination thresholds and points of subjective equality. Findings are discussed in the context of theoretical assumptions about clock resetting, the representation of time, and independence of successive time intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
考虑塑性铰外移的钢框架梁柱连接设计 总被引:16,自引:0,他引:16
介绍美国联邦突发事件管理局 (FEMA)对 1 994年北岭地震中焊接钢框架节点破坏原因的正式解释 ,说明塑性铰外移的必要性。此外 ,还介绍了塑性铰外移的两种基本形式以及狗骨式 (RBS)连接的有关设计规定和适用条件 ,其设计方法可供我国工程设计人员参考。 相似文献
38.
分析D.yn11配电变压器低压倒发生不同类型故障时,流过高压侧各相电流的大小及相位,从而比较保护用电流互感器在不同接线方式时过电流保护的灵敏度及可靠性;并提出过电流保护应注意的问题。 相似文献
39.
A novel current source inverter system interconnected to the single‐phase grid is proposed. It has the same construction as the conventional three‐phase current source inverter that is interconnected to the single‐phase three‐wire distribution system. Though the proposed circuit has no output transformer, it can be equivalently performed as the single‐phase double cascade inverter by diverting the pole transformer in the utility system. By controlling the appropriate scheme, the output currents can be obtained as the five‐level waveforms and their distortions can be decreased sufficiently. It is applied to the interactive electric energy storage system with batteries and the basic discharging characteristics are discussed experimentally. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10380 相似文献
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