Review and comparison of methods to study the contribution of variables in artificial neural network models
Convinced by the predictive quality of artificial neural network (ANN) models in ecology, we have turned our interests to their explanatory capacities. Seven methods which can give the relative contribution and/or the contribution profile of the input factors were compared: (i) the ‘PaD’ (for Partial Derivatives) method consists in a calculation of the partial derivatives […]
GENERALIZED CONTINUED FRACTION BASED ASYNCHRONOUS STREAM CIPHER FOR IMAGE PROTECTION
In this paper, we are particulary interested by image protection. The conventional encryption standard may be not applicable to images, due to the digital images properties which are characterized with some intrinsic features such as highly pixel redundancy and correlation. We propose a new asynchronous stream cipher based on generalized continued fraction (GCF). The proposed […]
IMAGE CRYPTOSYSTEM BASED ON CHAOTIC MAP AND CONTINUED FRACTIONS
Recently, a variety of chaos-based cryptosystems have been proposed. Some of these novel chaotic encryption schemes are not very suitable for image encryption due to their density function which is not uniformly distributed or due to their small key space. In this paper, we propose a new scheme for image encryption based on the use […]