Abstract
The estimation of the harmonic content of an ADC output is fundamental to evaluate its suitability to perform according the requirements specified for an application. The use of the traditional frequency analysis leads to a large hardware overhead due to the amount of on-chip processing being involved, or to a large quantity of data to be transferred in case the processing is performed in a tester. This paper presents an algorithm capable of estimating the harmonics with similar accuracy but with the advantage of being more suitable for a BIST implementation, since it requires a reduced number of on-chip operations, and that only a small set of values has to be supplied outside the chip for further processing. It relies, on the fact that harmonics generated by an ADC are mathematical related with the polynomial coefficients of its transfer function. ADC offset and gain errors can also be measured.

Abstract

Abstract
Inductive Logic Programming (ILP) is a promising technology for knowledge extraction applications. ILP has produced intelligible solutions for a wide variety of domains where it has been applied. The ILP lack of efficiency is, however, a major impediment for its scalability to applications requiring large amounts of data. In this paper we propose a set of techniques that improve ILP systems efficiency and make then more likely to scale up to applications of knowledge extraction from large datasets. We propose and evaluate the lazy evaluation of examples, to improve the efficiency of ILP systems. Lazy evaluation is essentially a way to avoid or postpone the evaluation of the generated hypotheses (coverage tests). The techniques were evaluated using the IndLog system on ILP datasets referenced in the literature. The proposals lead to substantial efficiency improvements and are generally applicable to any ILP system.

Abstract
In this paper an application of constraint logic programming (CLP) to the resolution of nesting problems is presented. Nesting problems are a special case of the cutting and packing problems, in which the pieces generally have non-convex shapes. Because of their combinatorial optimization nature, nesting problems have traditionally been tackled by heuristics and in the recent past by meta-heuristics. When trying to formulate nesting problems as linear programming models, to achieve global optimal solutions, the difficulty of dealing with the disjunction of constraints arises. On the contrary, CLP deals easily with this type of relationships among constraints. A CLP implementation for the nesting problem is described for convex and non-convex shapes. The concept of nofit polygon is used to deal with the geometric constraints inherent to all cutting and packing problems. Computational results are presented. © 2003 Wiley Periodicals, Inc.

Abstract

Abstract
The variation in airborne pollen concentration of the Braga region (Portugal) was studied in springtime, during the flowering of Vitis vinifera. The data set was obtained for two consecutive years (1999 and 2000), using a Cour-type sampler. During this period, thirty-six taxa were observed in a total of 3,200 pollen grains m-3 of air (CPA). The main pollen types observed were Olea, Poaceae and Castanea, representing 74% of the pollen spectrum. The airborne pollen concentration (CPA) was significantly correlated with certain meteorological parameters. Pollen concentration was positively correlated with temperature and wind direction (East and Northeast) and negatively correlated with rainfall and number of rainy days.