Savannas are heterogeneous systems characterized by the coexistence of grasses and woody trees. Riparian zones are dynamic parts of savanna landscapes with structurally diverse woody vegetation. Growing recognition of the importance of the structural component of biodiversity has highlighted the need to understand the spatial distribution and temporal dynamics of woody structural diversity. Mos...

Visual tracking aims to match objects of interest in consecutive video frames. This paper proposes a novel and robust algorithm to address the problem of object tracking. To this end, we investigate the fusion of state-of-the-art image segmentation hierarchies and graph matching. More specifically, (i) we represent the object to be tracked using a hierarchy of regions, each of which is describe...

A novel indexing structure, join index hierarchy, is proposed to handle the \goto's on disk" problem in object-oriented query processing. The method constructs a hierarchy of join indices and transforms a sequence of pointer chasing operations into a simple search in an appropriate join index le, and thus accelerates navigation in object-oriented databases. The method extends the join index str...

First consider a set of deductive databases (DDBs), each of which consists of de nite clauses. Consider each DDB as a set object with a type f dc g, where dc speci es a language. We can add an object identi er to each DDB and introduce an extent hierarchy [Ma] between object identi ers. By using such a hierarchy, we can express various kinds of DDBs under the hierarchy, construct new DDBs dynam...

To make Quantitative Radiology a reality in routine radiological practice, computerized automatic anatomy recognition (AAR) becomes essential. Previously, we presented a fuzzy object modeling strategy for AAR. This paper presents several advances in this project including streamlined definition of open-ended anatomic objects, extension to multiple imaging modalities, and demonstration of the sa...

This work on texture detection was inspired by the general problem of object recognition in two dimensional still images. One of the crucial challenges associated with the object recognition is selecting and obtaining discriminative features. In analysis of real scenes, like nature or urban places, many objects contain textures, which can be considered as one of the object features. Texture det...

A meaningful image segmentation groups the pixels into disjoint regions that consist of uniform components. Facing absence of contextual knowledge, the only alternative which can enrich our knowledge concerning the significance of our segmented groups is the creation of a hierarchy guided by the knowledge which emerges from the superficial and deep image structure [1]. In the present work, we d...

Image classification is a critical task for both humans and computers. One of the challenges lies in the large scale of the semantic space. In particular, humans can recognize tens of thousands of object classes and scenes. No computer vision algorithm today has been tested at this scale. This paper presents a study of large scale categorization including a series of challenging experiments on ...

Visibility culling of a scene is a crucial stage for interactive graphics applications, particularly for scenes with thousands of objects. The culling time must be small for it to be effective. A hierarchical representation of the scene is used for efficient culling tests. However, when there are multiple view frustums (as in a tiled display wall), visibility culling time becomes substantial an...