College of Science

A theoretical investigation is carried out by using an analytical expression for paraxial trajectory of an electron in a magnetic lens to estimate the optimum properties of the magnetic lens.The aberration coefficients of the magnetic lens are studied, such as the spherical, chromatic, radial distortion and spiral distortion aberration coefficients. The Glaser's bell-shaped model is adopted to represent the axial field distribution of magnetic lens.

    The recognition process is an important task in many applications of computer image analysis based on color or texture features. In this research, a texture recognition system has been introduced. The first stage is called the preprocessing stage. In this stage, a number of color transforms have been done on the training images to produce a set of bands (R, G, B, Gray, Y, I, Q, H, S, and V bands). From these bands, two sets of features vectors had been extracted, (i.e., density slicing and Fourier transform).

          Ferroelectric materials posses spontaneous polarization which can be reverse by applying an external electric field over a certain temperature range. Ferroelectric materials belong to special types of
crystals (non-centrosymmetric structure). Ferroelectric materials have a lot of industrial applications in medicine, environment and communications, etc. There are Many  ferroelectric materials such as