We propose a novel approach for solving the perceptual grouping problem in vision. Rather than fo-cusing on local features and their consistencies in the image data, our approach aims at extracting the global impression of an image. We treat image segmenta-tion as a graph partitioning problem and propose a novel global criterion, the normalized cut, for segmenting the graph. The normalized cut ...

Retinal vessel segmentation is an essential step of the diagnoses of various eye diseases. In this paper, we propose an automatic, efficient and unsupervised method based on gradient matrix, the normalized cut criterion and tracking strategy. Making use of the gradient matrix of the Lucas-Kanade equation, which consists of only the first order derivatives, the proposed method can detect a candi...

The determination of the relative position and pose of every robot in a modular robotic ensemble is a necessary preliminary step for most modular robotic tasks. Localization is particularly important when the modules make local noisy observations and are not significantly constrained by interrobot latches. In this paper, we propose a robust hierarchical approach to the internal localization pro...

In recent years it has been shown that clustering and segmentation methods can greatly benefit from the integration of prior information in terms of must-link constraints. Very recently the use of such constraints has been integrated in a rigorous manner also in graph-based methods such as normalized cut. On the other hand spectral clustering as relaxation of the normalized cut has been shown t...

This paper presents a validated protocol, using a novel, specifically formulated medium, to perform broth microdilution antimicrobial susceptibility assays of the salmonid bacterial pathogen Piscirickettsia salmonis. The minimum inhibitory concentrations (MIC) for florfenicol and oxytetracycline against 58 P. salmonis isolates recovered from various outbreaks occurred in Chilean salmonid farms ...

This study evaluated gender differences in the magnitude and timing of hamstring and quadriceps activation during activities that are believed to cause anterior cruciate ligament (ACL) injuries. Twelve men (age = 21.0 +/- 1.2 years; body mass = 81.61 +/- 13.3 kg; and jump height = 57.61 +/- 10.15 cm) and 12 women (age = 19.91 +/- 0.9 years; body mass = 64.36 +/- 6.14 kg; and jump height = 43.28...

In computer vision, segmentation is the process of partitioning digital image into multiple regions (sets of pixels), according to some homogeneity criterion. The problem of segmentation is a well-studied one in literature and there are a wide variety of approaches that are used. Graph cuts has emerged as a preferred method to solve a class of energy minimization problems such as Image Segmenta...

The problem of slow drilling in deep shale formations occurs worldwide causing significant expenses to the oil industry. Bit balling which is widely considered as the main cause of poor bit performance in shales, especially deep shales, is being drilled with water-based mud. Therefore, efforts have been made to develop a model to diagnose drilling effectivity. Hence, we arrived at graphical cor...

In this class, we introduced the random walk on graphs. The last lecture shows Perron-Frobenius theory to the analysis of primary eigenvectors which is the stationary distribution. In this lecture we will study the second eigenvector. To analyze the properties of the graph, we construct two matrices: one is (unnormalized) graph Laplacian and the other is normalized graph Laplacian. In the first...