As the number of users connects to the internet increases rapidly, Electronic mail (E-mail) is quickly becoming one of the fastest and most economical forms of communication available, since E-mail is extremely cheep and easy to send. As our lives have become ever increasingly tied up to the online world, the volume of E-mails coming into our inboxes has also been increasing, so the problem of email filtering is a critical one.
Personalized support for learners became even more important when e-learning take place in distributed database system.This research provides access to learning resources in a distributed e-learning database and it intends to adapt the system to the learner’s needs (personal needs) so that each learner gets the idea that the system was created just for him and knows what he likes.
Audio signals are often contaminated by background environment noise from audio equipments. Audio denoising aims to attenuating the noise while retaining the underlying signals.The focal point of this thesis is to use digital signal processing techniques based on wavelet transform to reduce the noise from the signal. In this research three types of wavelet transform (Haar, D4 and D6 wavelet transforms) and different thresholding criteria have been investigated to truncate the noise from two types of signal (high and low amplitude audio signals).
