BACKGROUND It has been shown that visual geometrical shape categories (rectangle and triangle) are graded structures organized around a prototype as demonstrated by perception and production tasks in adults as well as in children. The visual prototypical shapes are better recognized than other exemplars of the categories. Their existence could emerge from early exposure to these prototypical sh...

Coherent detection in combination with digital signal processing has recently enabled significant progress in the capacity of optical communications systems. This improvement has enabled detection of optimum constellations for optical signals in four dimensions. In this paper, we propose and investigate an algorithm for the blind adaptive equalization of one such modulation format: polarization...

This paper introduce the forward linear prediction for equalization of OFDM systems in space time channels. We shown by simulations that linear prediction structure have better performance that MERRY algorithm both to exploit space time diversity than tracking channel variations along of time. Keywords—OFDM, Blind Channel Shortening, Linear Multichannel Prediction, SIMO, MERRY, Second Order Sta...

We report a key proof of principle of a new acceleration method [Modeling Employing Limited Data (MELD)] for predicting protein structures by molecular dynamics simulation. It shows that such Boltzmann-satisfying techniques are now sufficiently fast and accurate to predict native protein structures in a limited test within the Critical Assessment of Structure Prediction (CASP) community-wide bl...

Mental rotation in the congenitally blind was investigated with a haptic letter-judgment task. Blind subjects and blindfolded, sighted subjects were presented a letter in some orientation between 0° to 300° from upright and timed while they judged whether it was a normal or mirror-image letter. Both groups showed an increasing response time with the stimulus’s departure from upright; this resul...

Residue analysis has become a frequently applied method for identifying prehistoric stone tool use. Residues adhering to the stone tool with varying frequencies are interpreted as being the result of an intentional contact with the worked material during use. Yet, other processes during the life cycle of a stone tool or after deposition may leave residues and these residues may potentially lead...

In Zimbabwe there are no comprehensive programmes to assist visually impaired school leavers to find employment. The problems faced by visually impaired people in getting employment were the thrust of this study. The study was carried out in Mashonaland East, Mashonaland West, Masvingo and Harare provinces. Using questionnaires, data were collected from 20 unemployed and 20 employed visually im...

The objective of the research reported below is the improvement of the intelligibility and naturalness of speech produced by an automatic synthesis-by-rule system. Such a system would be a major component of a reading machine for the blind . Work is reported below on the development and testing of a synthesis program and of rules for synthesis, and on phonetic investigations in support of rule ...