Many ant species have morphologically distinct worker sub-castes. This presumably increases colony efficiency and is thought to be optimized by natural selection. Optimality arguments are, however, often lacking in detail. In ants, the benefits of having workers in a range of sizes have rarely been explained mechanistically. In Atta leafcutter ants, large workers specialize in defence and also ...

Understanding finite-size effects is one of the key open questions in solving planar AdS/CFT. In this paper we discuss these effects in the AdS5×S string theory at one-loop in the world-sheet coupling. First we provide a very general, efficient way to compute the fluctuation frequencies, which allows to determine the energy shift for very general multi-cut solutions. Then we apply this to two-c...

Let (G, T ) be an instance of the (vertex) multiway cut problem where G is a graph and T is a set of terminals. For t ∈ T , a set of nonterminal vertices separating t from T \ {T } is called an isolating cut of t. The largest among all the smallest isolating cuts is a natural lower bound for a multiway cut of (G, T ). Denote this lower bound by m and let k be an integer. In this paper we propos...

background: we investigated whether the lungheart ratio parameter (lhr) can be used to identify the optimum cut off frequency for butterworth filter in 99mtc myocardial spect imaging. materials and methods: this study involved a cardiac phantom system consisting of cardiac insert in which 1.10 cm cold defect was inserted into its myocardium wall and filled with 4.0 μci/ml (0.148 mbq/ml) 99mtc c...

A local graph partitioning algorithm finds a cut near a specified starting vertex, with a running time that depends largely on the size of the small side of the cut, rather than the size of the input graph. In this paper, we present a local partitioning algorithm using a variation of PageRank with a specified starting distribution. We derive a mixing result for PageRank vectors similar to that ...

We study the solution quality for min-cut problems on graphs when restricting the shapes of the allowed cuts. In particular we are interested in min-cut problems with additional size constraints on the parts being cut out from the graph. Such problems include the bisection problem, separator problem, or the sparsest cut problem. We therefore aim at cutting out a given number m of vertices from ...

In this article, we study the effect of small-cut elements on critical time-step size in an immersogeometric context. We analyze different formulations for second-order (membrane) and fourth-order (shell-type) equations, derive scaling relations between cut-element various types cuts. particular, focus approaches weak imposition Dirichlet conditions: by penalty enforcement with Nitsche's method...

We show that the Min Cut Linear Arrangement Problem (Min Cut) is NP-complete for trees with polynomial size edge weights and derive from this the NP-completeness of Min Cut for planar graphs with maximum vertex degree 3. This is used to show the NP-completeness of Search Number, Vertex Separation, Progressive Black/ White Pebble Demand, and Topological Bandwidth for planar graphs with maximum v...

In recent years many algorithms have been proposed in the literature for solving the Max-Cut problem. In this paper we report on the application of a new Tabu Search algorithm to large scale Max-cut test problems. Our method provides best known solutions for many well-known test problems of size up to 10,000 variables, although it is designed for the general unconstrained quadratic binary progr...