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11.
For a set S of n points in convex position in the plane, let P(S) denote the set of all plane spanning paths of S. The geometric path graph of S, denoted by Gn, is the graph with P(S) as its vertex set and two vertices P,Q∈P(S) are adjacent if and only if P and Q can be transformed to each other by means of a single edge replacement. Recently, Akl et al. [S.G. Akl, K. Islam, H. Meijer, On planar path transformation, Inform. Process. Lett. 104 (2007) 59-64] showed that the diameter of Gn is at most 2n−5. In this note, we derive the exact diameter of Gn for n?3. 相似文献
12.
针对单晶硅生长过程中的直径测量,提出一种“不在同一条直线上的三点确定圆”的直径测量算法.首先对获取到的单晶生长图像进行图像预处理,提取单晶体的边缘信息,然后基于“不在同一条直线上的三点确定圆”的原理,对部分“释热光环”提取特征点,从而获取硅单晶直径像素值,再通过量纲转化把直径像素值转化为长度值.试验表明,该算法获得的硅单晶直径的准确率满足直径检测系统的要求. 相似文献
13.
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
14.
Makoto Sakamoto Kaoru Kajisa Naoko Tomozoe Takao Ito Hiroshi Furutani Michio Kono Satoshi Ikeda 《Artificial Life and Robotics》2008,13(1):61-64
In 1997, C.R. Dyer and A. Rosenfeld introduced an acceptor on a two-dimensional pattern (or tape), called the pyramid cellular acceptor, and demonstrated that many useful recognition tasks are executed by pyramid cellular acceptors in time proportional to the
logarithm of the diameter of the input. They also introduced a bottom-up pyramid cellular acceptor which is a restricted version of the pyramid cellular acceptor, and proposed some interesting open problems of the bottom-up
pyramid cellular acceptors. On the other hand, we think that the study of threedimensional automata has been meaningful as
the computational model of three-dimensional information processing such as computer vision, robotics, and so forth. In this
paper, we investigate about bottom-up pyramid cellular acceptors with three-dimensional layers, and show their some accepting
powers.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
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介绍了合作开发轧辊表面激光强化处理技术的初步实践,以及激光的强化机制、应用效果,对使用激光处理轧辊在生产中暴露出来的问题提出了解决方案。 相似文献
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分析了精密轧辊磨床常见磨削缺陷的几何形态、产生原因和影响因素,提出了消除和预防轧辊表面磨削缺陷的分析方法与措施,并以实例证明了其实用性和正确性。 相似文献
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