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961.
Antonio?Di Crescenzo Barbara?MartinucciEmail author Shelemyahu?Zacks 《Methodology and Computing in Applied Probability》2018,20(1):333-352
We investigate the one-dimensional telegraph random process in the presence of an elastic boundary at the origin. This process describes a finite-velocity random motion that alternates between two possible directions of motion (positive or negative). When the particle hits the origin, it is either absorbed, with probability α, or reflected upwards, with probability 1?α. In the case of exponentially distributed random times between consecutive changes of direction, we obtain the distribution of the renewal cycles and of the absorption time at the origin. This investigation is performed both in the case of motion starting from the origin and non-zero initial state. We also study the probability law of the process within a renewal cycle. 相似文献
962.
963.
In this paper after extending the definition of symplectic duality [given in Di Scala and Loi (Adv Math 217:2336–2352, 2008) for bounded symmetric domains] to arbitrary complex domains of \({{\mathbb{C}}^n}\) centered at the origin we generalize some of the results proved in Di Scala and Loi (Adv Math 217:2336–2352, 2008) and Di Scala et al. (Trans Groups 13(2):283–304, 2008) to those domains. 相似文献
964.
We consider a type of covering problem in cellular networks. Given the locations of base stations, the problem amounts to determining cell coverage at minimum cost in terms of the power usage. Overlap between adjacent cells is required in order to support handover. The problem we consider is NP-hard. We present integer linear models and study the strengths of their continuous relaxations. Preprocessing is used to reduce problem size and tighten the models. Moreover, we design a tabu search algorithm for finding near-optimal solutions effectively and time-efficiently. We report computational results for both synthesized instances and networks originating from real planning scenarios. The results show that one of the integer models leads to tight bounds, and the tabu search algorithm generates high-quality solutions for large instances in short computing time. 相似文献
965.
Néstor E. Aguilera Silvia C. Di Marco Mariana S. Escalante 《European Journal of Operational Research》2010
We address the problem of finding a suitable definition of a value similar to that of Shapley’s, when the games are defined on a subfamily of coalitions with no structure. We present two frameworks: one based on the familiar efficiency, linearity and null player axioms, and the other on linearity and the behavior on unanimity games. We give several properties and examples in each case, and give necessary and sufficient conditions on the family of coalitions for the approaches to coincide. 相似文献
966.
Di Zhao 《Journal of Computational and Applied Mathematics》2010,235(3):850-869
In this study, we propose a 3D generalized micro heat transfer model in an N-carrier system with the Neumann boundary condition in spherical coordinates, which can be applied to describe the non-equilibrium heating in biological cells. Two improved unconditionally stable Crank-Nicholson schemes are then presented for solving the generalized model. In particular, we delicately adjust the location of the interior grid point that is next to the boundary so that the Neumann boundary condition can be applied directly without discretization. As such, a second-order accurate finite difference scheme without using any fictitious grid points is obtained. The convergence rates of the numerical solution are tested by an example. Results show that the convergence rates of the present schemes are about 2.0 with respect to the spatial variable r, which improves the accuracy of the Crank-Nicholson scheme coupled with the conventional first-order approximation for the Neumann boundary condition. 相似文献
967.
格点系统存在指数吸引子的充分条件及应用 总被引:1,自引:0,他引:1
本文给出了一般格点动力系统存在指数吸引子的充分条件,然后将得到的结果应用到下面的格点非线性Schr(o|¨)dinger方程:iu_m-γ(2u_m-u_(m+1)-u_(m-1))+iκu_m+δ|u_m|~(2σ)u_m=g_m,m∈Z.设γ,κ,δ,σ和g_m满足适当的条件,证明了该格点方程存在指数吸引子. 相似文献
968.
We present a uniform version of Di Nola Theorem, this enables to embed all MV-algebras of a bounded cardinality in an algebra of functions with values in a single non-standard ultrapower of the real
interval [0,1]. This result also implies the existence, for any cardinal α, of a single MV-algebra in which all infinite MV-algebras of cardinality at most α embed. Recasting the above construction with iterated ultrapowers, we show how to construct such an algebra of values in a definable way, thus providing a sort of “canonical” set of values for the functional representation. 相似文献
969.
Thermal stability and thermodynamic properties of hybrid proton-conducting polyaryl etherketones 总被引:1,自引:0,他引:1
Marani D Di Vona ML Traversa E Licoccia S Beurroies I Llewellyn PL Knauth P 《The journal of physical chemistry. B》2006,110(32):15817-15823
The thermal and structural stability of sulfonated cross-linked PEEK (polyether ether ketone) and its silicon-containing class II hybrid derivatives were characterized by combination of mass spectrometry, infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. Thermodynamic properties of the hybrids were determined, including glass-transition temperature, degree of crystallinity, and thermal stability. The decomposition processes of the hybrid polymers could be consistently interpreted and their energetics quantitatively determined. The introduction of inorganic silanol moieties improves the thermal stability compared to sulfonated products. 相似文献
970.
Cavallari M Calzolari A Garbesi A Di Felice R 《The journal of physical chemistry. B》2006,110(51):26337-26348
We present a molecular dynamics investigation of guanine quadruple helices based on classical force fields. We analyze the dependence of the helical conformation on various compositional factors, such as the length of the G4-wire, as well as the incorporation into the helix channel of alkali ions of different species and in different amounts. In compliance with previous indications, our results suggest that monovalent alkali cations assist the stability of the quadruplex arrangement against disruption on the few nanoseconds time scale in the order of increasing van der Waals radius. Whereas very short G4-wire fragments immediately unfold in the absence of coordinating metal ions or in the presence of tiny ions (e.g., Li+) in agreement with the experimental evidence that empty short guanine quadruplexes are not formed in any synthetic conditions, our simulations show that longer empty helices do not discompose. This finding supports the possibility of producing long G4-wires with different guanine-cation stoichiometries than those routinely known. The classical trajectories allow us to identify different stationary axial sites for the different metal species, which are confirmed by complementary quantum calculations. 相似文献