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An efficient scheme for establishing a multicast route in packet networks is constructing a tree-shaped path in which multicast packets are replicated at specific branching nodes, called “copy nodes,” by the packet copy function and are forwarded to downstream nodes. This scheme leads to the efficient usage of network resources, but needs multicast routing control. To realize rapid multicast routing, it is suitable and realistic to restrict the number of copy nodes in calculating the multicast route. However, even in this approach we need to adequately select a limit on the number of copy nodes which satisfies the conditions of both priority for multicasting and geographical distribution. In this paper, a new copy-node allocation algorithm is proposed. This heuristic algorithm makes some “copy node functions” move on the network map sequentially according to attraction and repulsion determined by several conditions and finally makes them converge on the switching nodes suitable as copy nodes. In addition, the performance of this algorithm is evaluated by a computer simulation. This algorithm is applicable to various other server assignment problems. © 1999 Scripta Technica, Electron Comm Jpn Pt 1, 83(1): 87–96, 2000 [ABSTRACT FROM AUTHOR]

The neutron powder diffraction measurement of LiCo1/3Ni1/3Mn1/3O2 was carried out and the crystal structure and scattering density distribution were analyzed by Rietveld refinement and the maximum entropy method (MEM) to estimate the Li diffusing pathway. Rietveld refinement showed that the structure was basically the same as LiCoO2: a R-3 m space group, with Li and O mainly occupying the 3 a and 6 c sites, and Co, Ni, and Mn randomly occupying the 3 b site. Approximately 4% of the Li and Ni atoms exchanged their original sites (3 a and 3 b) to occupy 3 b and 3 a, respectively. Based on MEM analyses, we surmise that Li atoms moved on the (001), (003), and (00-3) planes and diffused through the 3 a–9 e–3 a sites on these planes. [ABSTRACT FROM AUTHOR]