We give algorithms for the directed minimum odd or even cut problem and certain generalizations. Our algorithms improve on the previous best ones of Goemans and Ramakrishnan by a factor of O(n) (here n is the size of the ground vertex set). Our improvements apply among others to the minimum directed Todd or T-even cut and to the directed minimum Steiner cut problems. The (slightly more general)...

We present a principled approach for general skin segmentation using graph cuts. We present the idea of a highly adaptive universal seed thereby exploiting the positive training data only. We model the skin segmentation as a min-cut problem on a graph defined by the image color characteristics. The prior graph cuts based approaches for skin segmentation do not provide general skin detection whe...

We study the problem k-Set Splitting in fixed parameter complexity. We show that the problem can be solved in time O∗(2.6494k), improving on the best currently known running time of O∗(8k). This is done by showing that a non-trivial instance must have a small minimal Set Cover, and using this to reduce the problem to a series of small instances of Max Sat. We also give a linear kernel containin...

the evaluation of the edge effects of forest roads on ecosystem is very useful to understand changes from forest road. with this regard, in this research the effect of main forest road construction on regeneration and biodiversity of established trees in edge of forest road was investigated at 35 m distance into forest area. an existing 10 years old road segment, with same physiographic propert...

We describe a simple greedy algorithm whose input is a set P of vertices on a combinatorial surface S without boundary and that computes a shortest cut graph of S with vertex set P . (A cut graph is an embedded graph whose removal leaves a single topological disk.) If S has genus g and complexity n, the running-time is O(n log n+(g + |P |)n). This is an extension of an algorithm by Erickson and...

A steganographer network corresponds to a graphic structure that the involved vertices (or called nodes) denote social entities such as the data encoders and data decoders, and the associated edges represent any real communicable channels or other social links that could be utilized for steganography. Unlike traditional steganographic algorithms, a steganographer network models steganographic c...

A new evaluation method is presented that employs cut sequence set (CSS) to analyze fault trees. A cut sequence is a set of basic events that fail in a specific order that can induce top event. CSS is the aggregate of all the cut sequences in a fault tree. The paper continues its former researches on CSS and uses CSS, composed of sequential failure expressions (SFE), to represent the occurrence...

A graph G is well-covered if all its maximal independent sets are of the same cardinality. Assume that a weight function w is defined on its vertices. Then G is w-well-covered if all maximal independent sets are of the same weight. For every graph G, the set of weight functions w such that G is w-well-covered is a vector space. Given an input graph G without cycles of length 4, 5, and 6, we cha...

The max-cut and stable set problems are two fundamental NP -hard problems in combinatorial optimization. It has been known for a long time that any instance of the stable set problem can be easily transformed into a max-cut instance. Moreover, Laurent, Poljak, Rendl and others have shown that any convex set containing the cut polytope yields, via a suitable projection, a convex set containing t...