We present a frame-invariant method for detecting coherent structures from Lagrangian flow trajectories that can be sparse in number, as is the case in many fluid mechanics applications of practical interest. The method, based on principles used in graph colouring and spectral graph drawing algorithms, examines a measure of the kinematic dissimilarity of all pairs of fluid trajectories, measure...

One of the great challenges in computer vision is automatic segmentation of objects in videos. This task becomes more difficult when image sequences are subject to low signal-to-noise ratio or low contrast between intensities of neighboring structures. Such challenging data are acquired routinely, for example, in medical imaging or satellite remote sensing. While individual frames can be analyz...

In this paper we propose a video segmentation algorithm that in the final delineation of the object employs the graph-cut. A partitioning of the image based on pairwise region comparison is done at the beginning of each frame. A set of keypoints is tracked over time via optical flow to extract regions, which are likely to be parts of the object of interest. The tracked keypoints contribute towa...

graph theory based methods are powerful means for representing structural systems so that their geometry and topology can be understood clearly. the combination of graph theory based methods and some metaheuristics can offer effective solutions for complex engineering optimization problems. this paper presents a charged system search (css) algorithm for the free shape optimizations of thin-wall...

Let graph energy is a graph--spectrum--based quantity‎, ‎introduced in the 1970s‎. ‎After a latent period of 20--30 years‎, ‎it became a popular topic of research both‎ ‎in mathematical chemistry and in ``pure'' spectral graph theory‎, ‎resulting in‎ ‎over 600 published papers‎. ‎Eventually‎, ‎scores of different graph energies have‎ ‎been conceived‎. ‎In this article we...

This paper develops adaptive graph filters that operate in reproducing kernel Hilbert spaces. We consider both centralized and fully distributed implementations. first define nonlinear on graph-shifted versions of the input signal. then propose a least mean squares (GKLMS) algorithm to identify filters' model parameters. To reduce dictionary size GKLMS, we apply principles coherence check rando...

To verify cache coherence protocols for distributed multi-processor architectures, we compare a state graph of the implementation with a speciication which is a state graph representing the simpliied behavior. The steps in the spec-iication correspond to atomic transactions, which are not atomic in the implementation. The method relies on an abstraction function which aggregates the implementat...

the chromatic number of a graph g, denoted by χ(g), is the minimum number of colors such that g can be colored with these colors in such a way that no two adjacent vertices have the same color. a clique in a graph is a set of mutually adjacent vertices. the maximum size of a clique in a graph g is called the clique number of g. the turán graph tn(k) is a complete k-partite graph whose partition...

A new method is proposed for parameterized reasoning about snoopy cache coherence protocols. The method is distinctive for being exact (sound and complete), fully automatic (algorithmic), and tractably efficient. The states of most cache coherence protocols can be organized into a hierarchy reflecting how tightly a memory block in a given cache state is bound to the processor. A broad framework...