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81.
Let G be a connected graph and D(G) be its distance matrix. In this article, the Smith normal forms of the integer matrices D(G) are determined for trees, wheels, cycles, complements of cycles and are reduced for complete multipartite graphs. 相似文献
82.
K. L. Patra 《Linear and Multilinear Algebra》2013,61(4):381-397
Consider a tree Pn-g,g , n≥ 2, 1≤ g≤ n-1 on n vertices which is obtained from a path on [1,2,?…?,n-g] vertices by adding g pendant vertices to the pendant vertex n-g. We prove that over all trees on n?≥?5 vertices, the distance between center and characteristic set, centroid and characteristic set, and center and centroid is maximized by trees of the form Pn-g,g , 2?≤?g?≤?n-3. For n≥ 5, we also supply the precise location of the characteristic set of the tree Pn-g,g , 2?≤?g?≤?n-3. 相似文献
83.
Marcin KRZYWKOWSKI 《数学年刊B辑(英文版)》2013,34(5):765-776
A 2-dominating set of a graph G is a set D of vertices of G such that every vertex of V(G)\D has at least two neighbors in D.A total outer-independent dominating set of a graph G is a set D of vertices of G such that every vertex of G has a neighbor in D,and the set V(G)\D is independent.The 2-domination(total outer-independent domination,respectively)number of a graph G is the minimum cardinality of a 2-dominating(total outer-independent dominating,respectively)set of G.We investigate the ratio between2-domination and total outer-independent domination numbers of trees. 相似文献
84.
Z. Abid 《Microelectronics Journal》2008,39(12):1509-1515
Five hybrid full adder designs are proposed for low power parallel multipliers. The new adders allow NAND gates to generate most of the multiplier partial product bits instead of AND gates, thereby lowering the power consumption and the total number of needed transistors. For an 8×8 implementation, the ALL-NAND array multiplier achieves 15.7% and 7.8% reduction in power consumption and transistor count at the cost of a 6.9% increase in time delay compared to standard array multiplier. The ALL-NAND tree multiplier exhibits lower power consumption and transistor count by 12.5% and 7.3%, respectively, with a 4.4% longer time delay, compared to conventional tree multiplier. 相似文献
85.
The classical strategy of multimodal interactions is to simultaneously utilise several modalities offered on a ‘single’ device.
However, practical restrictions appear, especially in mobile communications, due to the limitations of device’s interfaces
and the continuously changing communication conditions. Taking multimodality out of this single-device scenario, this paper
introduces a theoretical framework for dynamic Multi User Interfaces-Device Binding (MID-B). MID-B facilitates dynamic adaptation
and customisation of physically distributed devices (and their user interfaces) into one ‘virtual’ multimodal environment,
thus introducing ambient awareness into user interfaces. In MID-B, one device assumes the role of a “controller” which detects
and binds the interfaces and modalities available on devices in the vicinity. After discovery, it binds these modalities to
deliver the actual mobile service.
相似文献
Klaus MoessnerEmail: |
86.
Free vibration of polar orthotropic circular plates with elastic growth stresses and drying stresses
This study was performed to analyze effect of transverse growth stresses and drying stresses on natural frequencies of transverse free vibration of thin tree disk with free boundary condition. Using Rayleigh-Ritz method and finite element method, explicit closed form expression was derived for homogeneous orthotropic circular plates with internal stresses, which enables to predict both the effects of growth stresses, drying stresses, and combined growth and drying stresses on the natural frequency changes. This model can be used for predicting growth stresses from known natural frequencies. The same approach can also be undertaken to validate models visco-elastic drying stresses. 相似文献
87.
88.
We classify the trees on vertices with the maximum and the minimum number of certain generalized colorings, including conflict-free, odd, non-monochromatic, star, and star rainbow vertex colorings. We also extend a result of Cutler and Radcliffe on the maximum and minimum number of existence homomorphisms from a tree to a completely looped graph on vertices. 相似文献
89.
90.
A stable set in a graph G is a set of mutually non-adjacent vertices, α(G) is the size of a maximum stable set of G, and is the intersection of all its maximum stable sets. It is known that if G is a connected graph of order n≥2 with 2α(G)>n, then , [V.E. Levit, E. Mandrescu, Combinatorial properties of the family of maximum stable sets of a graph, Discrete Applied Mathematics 117 (2002) 149-161; E. Boros, M.C. Golumbic, V.E. Levit, On the number of vertices belonging to all maximum stable sets of a graph, Discrete Applied Mathematics 124 (2002) 17-25]. When we restrict ourselves to the class of trees, we add some structural properties to this statement. Our main finding is the theorem claiming that if T is a tree of order n≥2, with 2α(T)>n, then at least two pendant vertices an even distance apart belong to . 相似文献