This paper presents some theoretical considerations about the variance of a fuzzy set and introduces covering–based algorithm for computing bounds an interval Type–2 set. The proposed obtains all possible variances unlike other algorithms which are based on center centroid to obtain relative is proven be always bigger than absolute variance. A comparison given through different examples where s...

The term interval is quite generic. Time intervals mark the duration of events (the lifespan of a person). Alphabetic intervals have many applications (family names in the range A-C). Given the wide use of intervals, their handling is of major importance. However, there is a number of problems which relate to their management. Such of them were initially identified in research in temporal datab...

Spatial relationships are important ingredients for expressing constraints in retrieval systems for spatial databases. In this paper we propose a uniied representation of spatial relationships, 2D Projection Interval Relationships (2D-PIR), that integrates both directional and topological relationships. We propose a graph representation for pictures that is based on 2D-PIR. This graph represent...

We address the problem of approximating the 2-Interval Pattern problem over its various models and restrictions. This problem, which is motivated by RNA secondary structure prediction, asks to find a maximum cardinality subset of a 2-interval set with respect to some prespecified model. For each such model, we give varying approximation quality depending on the different possible restrictions i...

This paper presents the theory and design of interval type-2 fuzzy logic systems (FLSs) because of computational complexity of using general type-2 fuzzy set (T2FS) in type-2 fuzzy system. We propose an efficient and simplified method to compute the input and antecedent operations for interval type-2 FLSs; one that is based on a general inference formula for them. We introduce the concept of up...

We present an implementation of double precision interval arithmetic using the single-instruction-multiple-data SSE-2 instruction and register set extensions. The implementation is part of a package for exact real arithmetic, which defines the interval arithmetic variation that must be used: incorrect operations such as division by zero cause exceptions, loose evaluation of the operations is in...

In this paper we give a complete description of an interval type-2 fuzzy logic system based on geometry. We compare our novel defuzzification technique with type-reduction.