TY - CONF AB - In the multiway cut problem we are given a weighted undirected graph G=(V,E) and a set T⊆V of k terminals. The goal is to find a minimum weight set of edges E′⊆E with the property that by removing E′ from G all the terminals become disconnected. In this paper we present a simple local search approximation algorithm for the multiway cut problem with approximation ratio 2−2k . We present an experimental evaluation of the performance of our local search algorithm and show that it greatly outperforms the isolation heuristic of Dalhaus et al. and it has similar performance as the much more complex algorithms of Calinescu et al., Sharma and Vondrak, and Buchbinder et al. which have the currently best known approximation ratios for this problem. AU - Bloch-Hansen, Andrew AU - Samei, Nasim AU - Solis-Oba, Roberto ID - 9227 SN - 0302-9743 T2 - Conference on Algorithms and Discrete Applied Mathematics TI - Experimental evaluation of a local search approximation algorithm for the multiway cut problem VL - 12601 ER - TY - JOUR AB - The paper introduces an inertial extragradient subgradient method with self-adaptive step sizes for solving equilibrium problems in real Hilbert spaces. Weak convergence of the proposed method is obtained under the condition that the bifunction is pseudomonotone and Lipchitz continuous. Linear convergence is also given when the bifunction is strongly pseudomonotone and Lipchitz continuous. Numerical implementations and comparisons with other related inertial methods are given using test problems including a real-world application to Nash–Cournot oligopolistic electricity market equilibrium model. AU - Shehu, Yekini AU - Iyiola, Olaniyi S. AU - Thong, Duong Viet AU - Van, Nguyen Thi Cam ID - 8817 IS - 2 JF - Mathematical Methods of Operations Research SN - 1432-2994 TI - An inertial subgradient extragradient algorithm extended to pseudomonotone equilibrium problems VL - 93 ER - TY - JOUR AB - We consider inertial iteration methods for Fermat–Weber location problem and primal–dual three-operator splitting in real Hilbert spaces. To do these, we first obtain weak convergence analysis and nonasymptotic O(1/n) convergence rate of the inertial Krasnoselskii–Mann iteration for fixed point of nonexpansive operators in infinite dimensional real Hilbert spaces under some seemingly easy to implement conditions on the iterative parameters. One of our contributions is that the convergence analysis and rate of convergence results are obtained using conditions which appear not complicated and restrictive as assumed in other previous related results in the literature. We then show that Fermat–Weber location problem and primal–dual three-operator splitting are special cases of fixed point problem of nonexpansive mapping and consequently obtain the convergence analysis of inertial iteration methods for Fermat–Weber location problem and primal–dual three-operator splitting in real Hilbert spaces. Some numerical implementations are drawn from primal–dual three-operator splitting to support the theoretical analysis. AU - Iyiola, Olaniyi S. AU - Shehu, Yekini ID - 9315 IS - 2 JF - Results in Mathematics SN - 1422-6383 TI - New convergence results for inertial Krasnoselskii–Mann iterations in Hilbert spaces with applications VL - 76 ER - TY - JOUR AB - In this paper, we propose a new iterative method with alternated inertial step for solving split common null point problem in real Hilbert spaces. We obtain weak convergence of the proposed iterative algorithm. Furthermore, we introduce the notion of bounded linear regularity property for the split common null point problem and obtain the linear convergence property for the new algorithm under some mild assumptions. Finally, we provide some numerical examples to demonstrate the performance and efficiency of the proposed method. AU - Ogbuisi, Ferdinard U. AU - Shehu, Yekini AU - Yao, Jen Chih ID - 9365 JF - Optimization SN - 0233-1934 TI - Convergence analysis of new inertial method for the split common null point problem ER - TY - JOUR AB - The early development of many organisms involves the folding of cell monolayers, but this behaviour is difficult to reproduce in vitro; therefore, both mechanistic causes and effects of local curvature remain unclear. Here we study epithelial cell monolayers on corrugated hydrogels engineered into wavy patterns, examining how concave and convex curvatures affect cellular and nuclear shape. We find that substrate curvature affects monolayer thickness, which is larger in valleys than crests. We show that this feature generically arises in a vertex model, leading to the hypothesis that cells may sense curvature by modifying the thickness of the tissue. We find that local curvature also affects nuclear morphology and positioning, which we explain by extending the vertex model to take into account membrane–nucleus interactions, encoding thickness modulation in changes to nuclear deformation and position. We propose that curvature governs the spatial distribution of yes-associated proteins via nuclear shape and density changes. We show that curvature also induces significant variations in lamins, chromatin condensation and cell proliferation rate in folded epithelial tissues. Together, this work identifies active cell mechanics and nuclear mechanoadaptation as the key players of the mechanistic regulation of epithelia to substrate curvature. AU - Luciano, Marine AU - Xue, Shi-lei AU - De Vos, Winnok H. AU - Redondo-Morata, Lorena AU - Surin, Mathieu AU - Lafont, Frank AU - Hannezo, Edouard B AU - Gabriele, Sylvain ID - 10365 IS - 12 JF - Nature Physics SN - 1745-2473 TI - Cell monolayers sense curvature by exploiting active mechanics and nuclear mechanoadaptation VL - 17 ER -