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In this paper, teaching leaning based optimisation (TLBO) is used for maximising Shannon entropy or fuzzy entropy for effective image thresholding which leads to better image compression with higher peak signal to noise ratio (PSNR). The conventional multilevel thresholding methods are efficient when bi-level thresholding. However, they are computationally expensive extending to multilevel thresholding since they exhaustively search the optimal thresholds to optimise the objective functions. To overcome this drawback, a TLBO based multilevel image thresholding is proposed by maximising Shannon entropy or fuzzy entropy and results are compared with differential evolution, particle swarm optimisation and bat algorithm and proved better in standard deviation, PSNR, weighted PSNR and reconstructed image quality. The performance of the proposed algorithm is found better with fuzzy entropy compared to Shannon entropy.

Fingerprint recognition is one of the most popular methods used by Biometric identification systems for personnel identification. CORDIC algorithm provides wonderful solution to perform the math intensive operations at the cost of few components like adder, shifter, multiplexer.Etc. Such math intensive operations are required to perform during the image enhancement phase of finger print recognition process. In this paper CORDIC based architecture is proposed to evaluate almost all the trigonometric functions. This is implemented using XILINX ISE 13.2. Performance of the architecture is analyzed in terms of relative error.

Finger print recognition process involves many trigonometric evolutions. CORDIC based evolution of trigonometric functions is possible. In this paper CORDIC based architecture is proposed to evaluate the trigonometric or inverse trigonometric functions like sinθ, cosθ. Proposed architecture is partitioned into two main blocks: Magnitude generator and CORDIC processor. Magnitude generator outputs the value of the trigonometric function by driving the CORDIC processor. CORDIC processor executes the CORDIC rotations. Architecture Proposed in this paper is implemented using XILINX 13.2. Performance of the architecture is analyzed by calculating the relative error and resource utilization summery is reported.

The results of the measurement of natural radioactivity in soil collected from various locations of three districts of Rajasthan state using the gamma spectrometry technique are presented. The data on calculated and measured values of outdoor air absorbed dose rates due to terrestrial gamma radiation at each location are also discussed. It has been observed that the concentrations of the natural radionuclides viz., 40 K, 226 Ra and 232 Th in the soils vary from 50 to 137 Bq.kg -1 , from 30 to 78 Bq.kg -1 and from 43 to 106 Bq.kg -1 respectively. It has also been observed that on the average, the outdoor terrestrial gamma air absorbed dose rate is about 6.7 x 10 -8 Gy.h -1 for the three districts and the corresponding outdoor annual effective dose of 8.2 x 10 -5 Sv. Weak correlations have been observed between the concentration of 40 K and that of 226 Ra and 232 Th.

The authors present a classification of fiber-optic sensors based on modulation, with particular focus on one of the more stringent application areas of fiber-optic sensors, which is in avionics. Intensity modulation sensors, frequency modulation sensors, phase modulation sensors, wavelength distribution sensors, and polarization modulation are considered. Sensing of displacement, temperature, pressure acceleration, velocity, rotation, and magnetic fields are discussed. >