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61.
A Roman dominating function on a graph G is a function f : V(G) → {0, 1, 2} satisfying the condition that every vertex u for which f (u) = 0 is adjacent to at least one vertex v for which f (v) = 2. The weight of a Roman dominating function is the value f (V(G)) = ?u ? V(G) f (u){f (V(G)) = \sum_{u\in V(G)} f (u)}. The Roman domination number, γ
R
(G), of G is the minimum weight of a Roman dominating function on G. The Roman bondage number b
R
(G) of a graph G with maximum degree at least two is the minimum cardinality of all sets E¢ í E(G){E^{\prime} \subseteq E(G)} for which γ
R
(G − E′) > γ
R
(G). In this paper we present different bounds on the Roman bondage number of planar graphs. 相似文献
62.
Behzad Ramin Salehi Rad Mohammad Reza Nematollahi Nader 《Methodology and Computing in Applied Probability》2019,21(4):1045-1056
Methodology and Computing in Applied Probability - We consider a queueing system where some customers decide to simultaneously wait in two queues, rather than in a single queue, to receive their... 相似文献
63.
Ch. Zgheib E. Nassar M. Hamad R. Nader P. Masri J. Pezoldt G. Ferro 《Superlattices and Microstructures》2006,40(4-6):638
The effect of the germanium coverage prior to the epitaxial growth of 5 μm thick 3C-SiC on Si(100) substrates were evaluated with Atomic Force Microscopy and μ-Raman spectroscopy. The 3C-SiC layers were grown by atmospheric pressure chemical vapor deposition via a special procedure leading to layers with compressive instead of tensile stress. The Ge amount was varied from 0 up to 2 ML. The obtained results showed that the residual stress inside the layers is shifted in the compressive direction; the crystalline quality is improved with the Ge introduction but on the account of the surface roughness. These results open the route for the use of Ge-modified Si(100) as a potential substrate in order to improve the heteroepitaxial growth of 3C-SiC on silicon substrates. 相似文献
64.
A series of fused and spiro pyrazolones, isoxazolines, pyrimidines, β‐lactams, and thiazolidinones incorporating 4‐amino‐2‐methyl‐5,10‐dioxo‐1,5,10,11‐tetrahydrobenz[g]quinoline 3‐carbonitrile 1 and 4‐amino‐2‐methyl‐5,6,11‐trioxo‐1,4,4a,5,6,11,12,12a‐octahydro‐1,12‐diazanaphthacene 3‐carbonitrile 2. 7,8a‐c, 15,16a‐c, 19,20a‐d, 21,22a‐d , have been synthesised by cyclocondensation addition reaction and cycloaddition reaction of hydrazines, hydroxylamine, urea, thiourea, monochloroacetyl chloride and mercaptoacetic acid with the synthesised 15,16a‐c and 17,18a‐c . 相似文献
65.
66.
Let (T1, T2) be a non-negative random vector which is subjected to censoring random intervals [X1, Y1] and [X2, Y2]. The censoring mechanism is such that the available informations on T1 and T2 are expressed by a pair of random vectors W=(W1, W2) and δ=(δ1, δ2), where Wi=max(min(Yi, Ti), Xi) and In this paper we will show that under some mild conditions the joint survival function of T1 and T2 can be expressed uniquely as functional of observable joint survival functions. Our results extend recent works on the randomly right censored bivariate data case and on the univariate problem with double censoring to the bivariate data with double censoring. 相似文献
67.
Summary Definitions ofk-HNBUE andK-HNWUE are introduced and the relationship with other class of life distributions is studied. Various closure properties ofk-HNBUE (k-HNWUE) are proved. Finally bounds on the moments and survival function ofk-HNBUE (k-HNWUE) are given.
This research was supported by the ONR Grant N00014-78-C-0655. 相似文献
68.
It is shown how to identify potential signatures of noncommutative geometry within the decay spectrum of a muon in orbit near
the event horizon of a microscopic Schwarzschild black hole. This possibility follows from a re-interpretation of Moffat’s
nonsymmetric theory of gravity, first published in Phys. Rev. D 19:3554, 1979, where the antisymmetric part of the metric tensor manifests the hypothesized noncommutative geometric structure throughout
the manifold. It is further shown that for a given sign convention, the predicted signatures counteract the effects of curvature-induced
muon stabilization predicted by Singh and Mobed in Phys. Rev. D 79:024026, 2009. While it is unclear whether evidence for noncommutative geometry may become observable anytime soon, this approach at least
provides a useful direction for future quantum gravity research based on the ideas presented here. 相似文献
69.
Near-field imaging is a well-established technique in biomedical measurements, since closer to the detail of interest it is possible to resolve subwavelength details otherwise unresolved by regular lenses. A near-field scanning optical microscope (NSOM) tip may indeed overcome the resolution limits of far-field optics, but its proximity inherently perturbs the measurement. Here, we apply the recent concept of a "cloaked sensor" to an NSOM device in collection mode, showing theoretically how a proper plasmonic cover applied to an NSOM tip may drastically improve its overall measurement capabilities. 相似文献
70.
The in-plane and out-of-plane resistivities of both 2H-TaSe2 and 2H-NbSe2 were determined down to 10 K. For both compounds, the resistivity anisotropy shows notably a slope change at temperatures where a CDW transition is expected to occur. On the other hand, for both compounds the resistivity anisotropy at the lowest temperature of measurement is much greater than expected by the Lawrence–Doniach model, which relates the critical magnetic field anisotropy to the normal state resistivity anisotropy for 3D-anisotropic superconductors. 相似文献