In order to develop regression/classification models, QSAR analysis typically uses molecular descriptors as independent variables. The number of molecular descriptors has hugely increased over time and nowadays thousands of descriptors, able to describe different aspects of a molecule, can be calculated by means of dedicated software. However, when modelling a particular property or biological ...

Introduction: The main goal of SPECT imaging is to determine activity distribution inside the organs of the body. However, due to photon attenuation, it is almost impossible to do a quantitative study. In this paper, we suggest a mathematical relationship between activity distribution and its corresponding projections using a transfer matrix. Monte Carlo simulation was used to find a precise tr...

This paper describes a method for developing dimensional models from traditional Entity Relationship models. This can be used to design data warehouses and data marts based on enterprise data models. The first step of the method involves classifying entities in the data model into a number of categories. The second step involves identifying hierarchies that exist in the model. The final step in...

The objective of the paper is to put forward a general framework allowing the specification, comparison and conversion of most information and data models currently proposed for Information System design, be they at the conceptual or at the DBMS levels. That framework is based on an extended relational model that includes the concepts of entity domain and of complex domain. The analysis of the ...

Previous work on the solution to analytical electronic customer relationship management (eCRM) problems has used either data-mining (DM) or optimization methods, but has not combined the two approaches. By leveraging the strengths of both approaches, the eCRM problems of customer analysis, customer interactions, and the optimization of performance metrics (such as the lifetime value of a custom...

Let $X$ be an infinite set, equipped with a topology $tau$. In this paper we studied the relationship between $tau$, and ultrafilters on $X$. We can discovered, among other thing, some relations of the Robinson's compactness theorem, continuity and the separation axioms. It is important also, aspects of communication between mathematical concepts.

The relationship between handedness and mathematical ability is still highly controversial. While some researchers have claimed that left-handers are gifted in mathematics and strong right-handers perform the worst in mathematical tasks, others have more recently proposed that mixed-handers are the most disadvantaged group. However, the studies in the field differ with regard to the ages and th...

Previous studies have suggested that numerical processing relates to mathematical performance, but it seems that such relationship is more evident for intentional than for automatic numerical processing. In the present study we assessed the relationship between the two types of numerical processing and specific mathematical abilities in a sample of 109 children in grades 1-6. Participants were ...

In this paper we present a domain specific language (DSL) for Extended Entity-Relationship (EER) data model approach, named EERDSL. EERDSL is a part of our Multi-Paradigm Information System Modeling Tool (MIST) that provides EER database schema specification at the conceptual level and its transformation into a relational data model, or a class model. EERDSL modeling concepts are specified by E...

Topological indices play an important role in Mathematical Chemistry especially in the quantitative structure-property relationship (QSPR) and quantitative structureactivity relationship (QSAR). Recent research indicates that the augmented Zagreb index (AZI) possess the best correlating ability among several topological indices. The main purpose of the current study is to establish some mathema...