Krishnan Thampi, R; Dr. Sridhar, C S(Cochin University of Science & Technology, August , 1994)
[+]
[-]
Abstract:
A new procedure for the classification of lower case
English language characters is presented in this work . The
character image is binarised and the binary image is
further grouped into sixteen smaller areas ,called Cells .
Each cell is assigned a name depending upon the contour present in the cell and occupancy of the image contour in the cell. A data reduction procedure called Filtering is adopted to eliminate undesirable redundant information for
reducing complexity during further processing steps .
The filtered data is fed into a primitive extractor where
extraction of primitives is done .
Syntactic methods are employed for the classification of
the character . A decision tree is used for the interaction of the various components in the scheme . 1ike the
primitive extraction and character recognition. A character is recognized by the primitive by primitive construction
of its description . Openended inventories are used
for including variants of the characters and also adding
new members to the general class . Computer implementation
of the proposal is discussed at the end using handwritten
character samples . Results are analyzed and suggestions
for future studies are made. The advantages of the proposal
are discussed in detail .
Description:
Department of Electronics, Cochin
University Of Science And Technology
Godfrey,Louis; Jacob,Philip(Department of Physics, 1994)
[+]
[-]
Abstract:
The thesis investigated the elastic properties and phase transitions in selected mixed sulphate crystals – Lithium Hydrazinium Sulphate [LiN2H2SO4], Lithium Ammonium Sulphate [LiNH4SO4] and Lithium Potassium Sulphate [LiKSO4] – using ultrasonic technique. The pulse echo overlap technique has been used for measuring ultrasonic velocity and its dependence on temperature along different directions with waves of longitudinal and transverse polarizations. Two major numerical techniques and the corresponding computer programs developed as part of present work are presented in this thesis. All the 9 elastic constants of LHS are determined accurately from ultrasonic measurements and applying misorientation correction refines the constants. Ultrasonic measurements are performed in LAS to determine the elastic constants and to study the low temperature phase transitions. Temperature variation studies of elastic constant of LAS are performed for 6 different modes of propagation for heating and cooling at low temperatures. All the 5 independent elastic constants of LPS is determined using ultrasonic measurements. It is concluded that LPS crystal does not undergo a phase transition near this temperature. A comparison of the three crystals studied shows that LPS has maximum number of phase transitions and LHS has the least number. It is interesting to note that LPS has the simplest formula unit among the three. There is considerable scope for the future work on these crystals and others belonging to the sulphate family.