In Global South countries, ageing is an incoming phenomenon with socio-spatial implications that are not much explored yet. North countries already facing trends significant territorial consequences, such as declining populations contribute to making certain areas marginal. However, different factors may determine the marginality of a municipality or region in other settings. Drawing on these p...

Orthogonal frequency division multiplexing (OFDM) has become a promising method for many wireless communication applications. However, one main drawback of OFDM systems is the high peak-to-average power ratio (PAPR). Selected mapping (SLM) is a well-known technique to decrease the problem of high PAPR in OFDM systems. In this method, transmitter is obliged to send some bits named side informati...

Mutual Information (MI) is a long studied measure of information content, and many attempts to apply it to feature extraction and stochastic coding have been made. However, in general MI is computationally intractable to evaluate, and most previous studies redefine the criterion in forms of approximations. Recently we described properties of a simple lower bound on MI, and discussed its links t...

In the past few decades, researchers have proposed many discriminant analysis (DA) algorithms for the study of high-dimensional data in a variety of problems. Most DA algorithms for feature extraction are based on transformations that simultaneously maximize the between-class scatter and minimize the withinclass scatter matrices. This paper presents a novel DA algorithm for feature extraction u...

According to a UNDP Report (1998), about 54% of Africa’s population is estimated to live in absolute poverty. Currently in Nigeria, rapid change and vigorous development in information technology (IT) is occurring, changing Nigerians’ way of life, as well as the country’s economic strength, national power, and international competitiveness. The status of a country or nation in the global politi...

Nonlinear dimensionality reduction has so far been treated either as a data representation problem or as a search for a lowerdimensional manifold embedded in the data space. A main application for both is in information visualization, to make visible the neighborhood or proximity relationships in the data, but neither approach has been designed to optimize this task. We give such visualization ...

There currently exists a bottleneck in extracting information from pre-existing texts to generate a symbolic representation of the text that can be used by a case-based reasoning (CBR) system. Symbolic case representations are used in legal and medical domains among others. Finding similar cases in the legal domain is crucial because of the importance precedents play when arguing a case. Furthe...

Nonlinear dimensionality reduction methods are commonly used for two purposes: (i) as preprocessing methods to reduce the number of input variables or to represent the inputs in terms of more natural variables describing the embedded data manifold, or (ii) for making the data set more understandable, by making the similarity relationships between data points explicit through visualizations. The...

Rough fuzzy sets are an effective mathematical analysis tool to deal with vagueness and uncertainty in the area of machine learning and decision analysis. Fuzzy information systems and fuzzy objective information systems exit in many applications and knowledge reduction in them can’t be implemented by reduction methods in Pawlak information systems. Therefore, this paper provides a model for ru...