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891.
In this study, we present a longitudinal analysis of the evolution of interorganizational disaster coordination networks (IoDCNs) in response to natural disasters. There are very few systematic empirical studies which try to quantify the optimal functioning of emerging networks dealing with natural disasters. We suggest that social network analysis is a useful method for exploring this complex phenomenon from both theoretical and methodological perspective aiming to develop a quantitative assessment framework which could aid in developing a better understanding of the optimal functioning of these emerging IoDCN during natural disasters. This analysis highlights the importance of utilizing network metrics to investigate disaster response coordination networks. Results of our investigation suggest that in disasters the rate of communication increases and creates the conditions where organizational structures need to move at that same pace to exchange new information. Our analysis also shows that inter-organizational coordination network structures are not fixed and vary in each period during a disaster depending on the needs. This may serve the basis for developing preparedness among agencies with an improved perspective for gaining effectiveness and efficiency in responding to natural disasters. 相似文献
892.
893.
Michael J. Hopkins 《Japanese Journal of Mathematics》2016,11(1):1-14
The history and solution of the Kervaire invariant problem is discussed, along with some of the future prospects raised by its solution. 相似文献
894.
895.
Zhinan Xia 《Mediterranean Journal of Mathematics》2016,13(3):1065-1086
In this paper, we investigate the existence, uniqueness and stability of pseudo almost periodic mild solution to nonautonomous impulsive integro-differential equations in Banach space. The working tools are based on the fixed point theorems and Gronwall–Bellman inequality. To illustrate our main results, we study pseudo almost periodic solution of the heat equations with Dirichlet conditions. 相似文献
896.
897.
Yury L. Karavaev Alexander A. Kilin Anton V. Klekovkin 《Regular and Chaotic Dynamics》2016,21(7-8):918-926
In this paper we describe the results of experimental investigations of the motion of a screwless underwater robot controlled by rotating internal rotors. We present the results of comparison of the trajectories obtained with the results of numerical simulation using the model of an ideal fluid. 相似文献
898.
J Pacheco A Alvarez I García F Angel-Bello 《The Journal of the Operational Research Society》2012,63(5):569-581
The work addressed in this paper is motivated from a real problem proposed to the authors by a bakery company in Northern Spain. The objective is to minimize the total distance travelled for the daily routes over the week. In order to reduce this total distance, some flexibility in the dates of delivery is introduced. A mixed-integer linear model for the problem is formulated. In addition, a two-phase method based in GRASP and path-relinking metaheuristic strategies is proposed. Computational experiments show that the method performs very well, obtaining high-quality solutions in short computational times. Moreover, when it is applied to real-data-based instances, the obtained solutions considerably reduce transportation costs over the planning horizon. 相似文献
899.
We prove an analog of the base change functor of Λ-trees in the setting of generalized affine buildings. The proof is mainly
based on local and global combinatorics of the associated spherical buildings. As an application we obtain that the class
of generalized affine buildings is closed under taking ultracones and asymptotic cones. Other applications involve a complex
of groups decompositions and fixed point theorems for certain classes of generalized affine buildings. 相似文献
900.
The existence of solution for the 2D-Keller-Segel system in the subcritical case, i.e. when the initial mass is less than
8π, is reproved. Instead of using the entropy in the free energy and free energy dissipation, which was used in the proofs (Blanchet
et al. in SIAM J. Numer. Anal. 46:691–721, 2008; Electron. J. Differ. Equ. Conf. 44:32, 2006 (electronic)), the potential energy term is fully utilized by adapting Delort’s theory on 2D incompressible Euler equation
(Delort in J. Am. Math. Soc. 4:553–386, 1991). 相似文献