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1.
On conditional diagnosability and reliability of the BC networks 总被引:1,自引:1,他引:0
Qiang Zhu 《The Journal of supercomputing》2008,45(2):173-184
An n-dimensional bijective connection network (in brief, BC network), denoted by X n , is an n-regular graph with 2 n nodes and n2 n?1 edges. Hypercubes, crossed cubes, twisted cubes, and Möbius cubes all belong to the class of BC networks (Fan and He in Chin. J. Comput. 26(1):84–90, [2003]). We prove that the super connectivity of X n is 2n?2 for n≥3 and the conditional diagnosability of X n is 4n?7 for n≥5. As a corollary of this result, we obtain the super connectivity and conditional diagnosability of the hypercubes, twisted cubes, crossed cubes, and Möbius cubes. 相似文献
2.
Bijective connection graphs (in brief, BC graphs) are a family of hypercube variants, which contains hypercubes, twisted cubes, crossed cubes, Möbius cubes, locally twisted cubes, etc. It was proved that the smallest diameter of all the known n-dimensional bijective connection graphs (BC graphs) is , given a fixed dimension n. An important question about the smallest diameter among all the BC graphs is: Does there exist a BC graph whose diameter is less than the known BC graphs such as crossed cubes, twisted cubes, Möbius cubes, etc., with the same dimension? This paper answers this question. In this paper, we find that there exists a kind of BC graphs called spined cubes and we prove that the n-dimensional spined cube has the diameter ⌈n/3⌉+3 for any integer n with n?14. It is the first time in literature that a hypercube variant with such a small diameter is presented. 相似文献
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Pyrolysis of BC dry chemical fire extinguishing powders which are useful for Class “B” and Class “C” fires was conducted on a thermogravimetric analyzer with sample loading of 10–25 mg under dynamic air atmosphere. The effect of particle sizes (medium value 48.99, 27.24, 4.93 µm) and heating rates (10, 15, and 20°C min?1) were examined. The pyrolysis kinetics of the samples was analyzed using a distribution activation energy model. It was found that the decomposition temperature decreased and the pyrolysis rate increased after the samples were milled. The agglomeration of particles during production did not have an appreciable influence on the pyrolysis process of the samples in our experimental conditions. The activation energy value was 77.13?219.78 kJ · mol?1, 58.18?288.67 kJ · mol?1, and 44.59?209.17 kJ · mol?1 for the powder of particle size 48.99, 27.24, 4.93 µm. We should use micro powder in fire extinguishing. 相似文献
5.
程学礼 《计算机与应用化学》2006,23(12):1222-1226
用Gaussian94程序包,在B3LYP/6-311 G**上对线型碳链BC2nB(n=1-5)进行了研究。它们属于D∞h点群.具有特殊的结构,用电子布居分析和振动模式分析来研究这种特殊结构。振动分析表明,属于平面弯曲和面内摇摆的振动模式是简并的,并且属于g对称性的所有面内弯曲和对称伸缩模式都没有或仅有很弱的IR活性。非对称伸缩模式(∑(?))总是有特别高的IR活性。 相似文献
6.
通过对生物质气、煤气及不同比例生物质气和煤气混合气体组成可燃成分对B/IGCC(或BC/IGCC)燃气轮机燃烧室效率影响的计算,定性地分析了燃料可燃组分对燃烧室效率的影响规律。结果表明:生物质燃料气比高、中、低热值煤气在燃烧室中的效率都高;燃料组分的相对含量对效率的影响程度较大,当H2体积百分含量在某一范围内时,燃料组分中CO的相对含量对燃烧室效率的影响程度比H2的影响大,在相同体积百分含S量条件下,CO在燃烧室中的效率比CH4高,在燃气轮机初温的提高受限的条件下,将含C量相同的燃料转化为CO气体比转化为CH4更有利于提高燃烧室效率。 相似文献
7.
Wang Jing Liu Zhanli Wang Yan You Xiaohu 《电子科学学刊(英文版)》2007,24(4):490-495
In this paper, the effect of channel estimation errors upon the Zero Forcing (ZF) precoding Multiple Input Multiple Output Broadcast (MIMO BC) systems was studied. Based on the two kinds of Gaussian estimation error models, the performance analysis is conducted under different power allocation strategies. Analysis and simulation show that if the covariance of channel estimation errors is independent of the received Signal to Noise Ratio (SNR), imperfect channel knowledge deteriorates the sum capacity and the Bit Error Rate (BER) performance severely. However, under the situation of orthogonal training and the Minimum Mean Square Error (MMSE) channel estimation, the sum ca- pacity and BER performance are consistent with those of the perfect Channel State Information (CSI) with only a performance degradation. 相似文献
8.
大气气溶胶碳组分存在形式多样,其化学和光学特征明显不同;因此基于不同的热和光行为的假设和分析步骤的碳组分分析方法导致碳组分测量结果的差异。本文基于文献调研与实验室分析介绍气溶胶碳组分分析仪器的基本性能指标,分析不同分析方法导致气溶胶碳组分的差异和成因。为了了解北京有机气溶胶特征,本文描述北京PM2.5中有机碳(OC)和元素碳(EC)变化特征并对北京秋、冬季PM,(大气中空气动力学直径≤1μm的颗粒物)中有机气溶胶进行了来源解析。结果表明,北京OC和EC在秋冬季呈现出较高的水平,采暖期OC浓度是非采暖期的1.2—1.8倍,EC浓度是非采暖期的1.1倍左右;秋季北京PM,中有机气溶胶(OA)主要来源于二次转化产生的氧化性有机气溶胶(OOA),机动车排放的烃类有机气溶胶(HOA)和餐饮排放有机气溶胶(COA);而冬季北京PM1中有机气溶胶主要来源于高度氧化的低挥发性的OOA,“新鲜”氧化的半挥发性的OOA,燃煤源有机气溶胶(CCOA)、烹饪源排放的COA和机动车排放的HOA。 相似文献
9.
通过简要分析煤矿液压支架大流量技术改造的必要性及理论依据,并确定液压支架大流量技术合理方案及工艺的改造,以煤矿BC480-22/42型液压支架为例,最后对煤矿液压支架大流量改造前后控制进行对比。 相似文献
10.