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The multihop optical network is the most appropriate solution to satisfy the increasing applications of Internet services. This paper extends the regular Kautz graph to one with multiple layers in order to produce more architectural variations. The connectivity between adjacent layers utilizes the systematic connection patterns of a regular Kautz graph. A routing algorithm based on its property is presented. Optical passive star (OPS) couplers are adopted to implement our new topologies. Three scheduling criteria that can solve the contention problem in the intermediate nodes are evaluated and compared in terms of their capability to improve the accessibility. 相似文献
3.
摩擦强度对薄膜表面形态的作用:原子力显微镜下的观察 总被引:2,自引:2,他引:0
展示了摩擦强度对聚酰亚胺薄膜表面形态的影响,原子力显微图像显示,机械摩擦会使聚酰亚胺薄膜表面上形成微沟槽,这些沟槽的表面具有丰富的表面精细构造。原子显微图像还揭示了机械摩擦可以改变被磨擦聚酰亚胺膜的表面形态。 相似文献
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Melt crystallization of isotactic polypropylene (iPP), containing crystallites of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide (DCNDCA) as a nucleating agent of the the β-phase iPP crystal, is carried out under a magnetic field (6 T) to obtain the alignment of the iPP crystal induced by magnetic alignment of DCNDCA. In a previous paper, DCNDCA was reported to undergo magnetic alignment in a liquid suspension. The obtained iPP sample exhibits alignment of the β-phase crystal with the c-axis aligned perpendicular to the magnetic field. The comparison of this alignment of iPP with the reported magnetic alignment of DCNDCA indicates that the β-phase crystal grows epitaxially on the DCNDCA crystal. The (330)β plane of the iPP crystal lies on the bc-plane of the DCNDCA crystal in which the direction of the c-axis of the iPP coincides with the direction of the b-axis of the DCNDCA crystal. 相似文献
6.
The viscoelastic properties of a three-arm and a four-arm star polybutadiene with the same arm molecular weight (Ma) were studied. The zero-shear recoverable compliance (J0e) and plateau modulus (G0N) for these stars are the same. The zero-shear viscosity (η0) of the three-arm star is 20% lower than that of the four-arm star. Mixtures of the stars had J0e and G0N unchanged. A mixture of the three- and four-arm star was diluted with a low molecular weight linear polybutadiene. G0N∝ø2; J0e∝ø?1 and Me∝ø?1, as expected for dilution with a θ-solvent. 相似文献
7.
Recent developments of high-performance NEOMAX magnets 总被引:6,自引:0,他引:6
For further improvement in achieving extremely high magnetic properties of Nd- Fe- B sintered magnets, extensive investigation
has been done to densify the magnet up to the theoretical value, to increase the volume fraction of the Nd
2Fe14B matrix phase, and to achieve a high degree of alignment. By controlling chemical composition and the amount of constituent
phases,improving particle size distribution, and adopting the isostatic pressing method to get better alignment of fine particles,
we have succeeded in obtaining a high-performance magnet having residual flux density (Br) of 1.495 T (14.95 kG), maximum energy product [(BH)max] of 431 kj/m3 (54.2 MGOe), and intrinsic coercivity (iHc) of 845 kA/m (10.62 kOe). 相似文献
8.
分析了太钢电弧炉变压器高压侧相间过电压的产生原因,比较了用于限制过电压的避雷器的两种接法.结论是用四垦接法MOA限制过电压的效果较显著. 相似文献
9.
Poly(ethylene oxide) (PEO) star polymers were prepared by anionic polymerization of methacryloyl chloride and glyceryl trimethacrylate with sec‐butyllithium in cyclohexane. The ensuing polymers were grafted with poly(ethylene glycol) of molecular weight 400. The final product was washed with methylene chloride and analyzed with infrared spectroscopy, differential scanning calorimetry, and thermogravimetry. Star polymers of PEO were also prepared by anionic polymerization of glycidol with sec‐butyllithium in cyclohexane. The initiator was chosen so as to yield a polymer of 10,000 molecular weight. The resulting polymers were analyzed by nuclear magnetic resonance, infrared spectroscopy, and thermogravimetry. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 322–327, 2003 相似文献
10.
本文提出了一种适合于特殊环境使用的光纤局域网的拓扑结构——类星型结构。这种结构解决了多通道的同时传输问题。此外,文中还对 OLAN 网的层次划分和各层的协议进行了分析和讨论。 相似文献