M. Stoer and F. Wagner and independently A. Frank have found a simple proof of the validity of Nagamochi and Ibaraki7s min-cut algorithm. This note points out some nice property of the behavior of Nagamochi and Ibaraki's rnin-cut algorithm, which also gives another simple proof of the validity of their algorithm. The proof relies only on the symmetric submodularity of the cut function. Hence, i...

A tree series over a semiring with partially ordered carrier set can be considered as a fuzzy set. We investigate conditions under which it can also be understood as a fuzzi ed recognizable tree language. In this sense, su cient conditions are presented which, when imposed, ensure that every cut set, i.e., the pre-image of a prime lter of the carrier set, is a recognizable tree language. Moreov...

1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2: Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3: The Classical Sequent Calculus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

In this note, we study the cut locus of the free, step two Carnot groups Gk with k generators, equipped with their left-invariant Carnot-Carathéodory metric. In particular, we disprove the conjectures on the shape of the cut loci proposed in [Mya02, Mya06] and [MM16a], by exhibiting sets of cut points Ck ⊂ Gk which, for k > 4, are strictly larger than conjectured ones. While the latter were, re...

Let an edge cut partition the vertex set of a graph into k disjoint subsets A1, . . . , Ak with ||Ai| − |Aj || ≤ 1. We consider the problem of determining the minimal size of such a cut for a given graph. For this we introduce a new lower bound method which is based on the solution of an extremal set problem and present bounds for some graph classes based on Hamming graphs.

We consider a new combinatorial optimization problem that combines network design and facility location aspects. Given a graph with two types of customers and two technologies that can be installed on the edges, the objective is to find a minimum cost subtree connecting all customers while the primary customers are served by a primary subtree that is embedded into the secondary subtree. In addi...

until now single values of irr are traditionally used to estimate the time value of cash flows. since uncertainty exists in estimating cost data, the resulting decision may not be reliable. the most commonly cited drawbacks to using the internal rate of return in evaluatton of deterministic cash flow streams is the possibility of multiple conflicting internal rates of return. in this paper we p...

We show that the following two problems are polynomiaUy equivalent: 1) Given a (weighted) graph G, and a cut C of G, decide whether C is maximal or not . 2) Given a (weighted) graph G, and a cut C of G, decide whether C is maximal or not , and in case it is not , find a better solution C'. As a consequence, an optimali ty testing oracle may be used to design a polynomial t ime algori thm for ap...

The suppression of the regenerative chatter phenomenon in turning process via the variation of the frequency and amplitude of the spindle motor excitation is carried out in this research. A programmable inverter is employed for variable periodic excitation of the spindle motor. A set of turning experiments is designed and performed on a number of conical work pieces both in constant spindle spe...

The suppression of the regenerative chatter phenomenon in turning process via the variation of the frequency and amplitude of the spindle motor excitation is carried out in this research. A programmable inverter is employed for variable periodic excitation of the spindle motor. A set of turning experiments is designed and performed on a number of conical work pieces both in constant spindle spe...