We propose a new model for natural image statistics. Instead of minimizing dependency between components of natural images, we maximize a simple form of dependency in the form of tree-dependencies. By learning filters and tree structures which are best suited for natural images we observe that the resulting filters are edge filters, similar to the famous ICA on natural images results. Calculati...

Ordered Model trees were introduced as a normal form for disjunctive deductive databases. They were also used to facilitate the computation of minimal models for disjunctive theories by exploiting the order imposed on the Herbrand base of the theory. In this work we show how the order on the Herbrand base can be used to compute perfect models of a disjunctive stratiied nite theory. We are able ...

In this paper, we study the different steps of translation from XML to relational models, while maintaining semantic constraints. Our work is based on the theory of regular tree grammars, which provides a useful formal framework for understanding various aspects of XML schema languages. We first study two normal form representations for regular tree grammars. The first normal form representatio...

In this paper we introduce the basic methodology for analyzing and debugging programs. We first convert programs into their loop-free equivalents and from this into the static single assignment form. From the static single assignment form we derive a corresponding constraint satisfaction problem. The constraint representation can be directly used for debugging. From the corresponding hyper-tree...

Estimating urban trees growth, especially tree height is very important in urban landscape management. The aim of the study was to predict of tree height base on tree diameter. To achieve this goal, 921 trees from five species were measured in five areas of Mashhad city in 2014. The evaluated trees were ash tree (Fraxinus species), plane tree (Platanus hybrida), white mulberry (Morus alba), ail...

PURPOSE To investigate the role of scleral creep in the axial elongation of chick and tree shrew eyes with induced myopia. METHODS Form-deprivation myopia was induced with a diffusing occluder worn over one eye. Scleral samples from the posterior pole and equatorial regions of myopic, contralateral (control), and age-matched normal chick and tree shrew eyes were loaded in vitro with a force o...

In this paper we present the tree to tree transduction language, TTT. We motivate the overall ”template-to-template” approach to the design of the language, and outline its constructs, also providing some examples. We then show that TTT allows transparent formalization of rules for parse tree refinement and correction, logical form refinement and predicate disambiguation, inference, and verbali...

We completely characterise the complexity in the decision tree model of computing composite relations of the form h = g◦ ( f 1, . . . , f n), where each relation f i is booleanvalued. Immediate corollaries include a direct sum theorem for decision tree complexity and a tight characterisation of the decision tree complexity of iterated boolean functions.

In this paper, we study the problem of compressing a data structure (e.g. tree, undirected and directed graphs) in an eecient way while keeping a similar structure in the compressed form. To date, there has been no proven optimal algorithm for this problem. We use the idea of building LZW tree in LZW compression to compress a binary tree generated by a stationary ergodic source in an optimal ma...