Active Noise Control using Variable step-size Griffiths’ LMS (VGLMS) algorithm on Real-Time platform

This paper proposes implementation of Griffith’s Variable step-size algorithm for Active Noise Control (ANC) on ADSP-TS201 EZ-Kit Lite. The dual computational units and execution of up to four instructions per cycle which are special features over other processors are best utilized to generate an optimized code. The VGLMS provides improved secondary path estimation and computations involved are marginal as the same gradient is used for step-size computation and coefficient adaptation. The improved secondary path estimate, in turn improves the ANC performance. Further, variable step-size algorithm is used for the main-path to achieve faster convergence. Both for narrowband (fundamental and its harmonics) and broadband noise fields, for a duct the attenuation achieved is 25 dB and 15 dB respectively. The program execution time was only 1.25% for an input sampling rate of 1 KHz which indicates the utility of the special features of the processor considered. Further these features have enabled in bringing down the program memory requirement in the implementation of the algorithm

Study on Airborne Pollen in the Atmosphere of Bangalore City

The atmospheric pollen of Jnana Bharathi campus, Bangalore University was surveyed during one year period from January 2011 to December 2011 using a vertical cylinder trap. A total of 28 pollen types were identified, among which 7 were present throughout the year. These belonged to Poaceae, Tridax sp., Eucalyptus sp., Parthenium hysterophorus, Cocus nucifera, Croton sparsiflorus and Mimosa pudica. The most predominant Pollen was Parthenium hysterophorus (23.87%) followed by Poaceae (16.19%), Mimosa Pudica (11.31%), Delonix regia (8.77%) and Eucalyptus spp. (7.58%) were found in the atmosphere of Bangalore city. Maximum pollen concentration was observed in the month of May (880/m3) followed by April (552/m3) and minimum in June (163/m3). The total pollens as well as individual pollen types displayed distinct seasonal periodicity in their incidence. The present study will provide preliminary but useful data to the allergologists for effective diagnosis and treatment of local population suffering from pollen hypersensitivity

Ocular Surface Squamous Neoplasia in Xeroderma Pigmentosum

Xeroderma pigmentosum (XP) is a rare genetic disorder associated with multiple oculocutaneous and neurological manifestations. It occurs due to deficiency of the enzymes responsible for repairing ultraviolet radiation-induced DNA damage. Persistence of un-repaired DNA results in somatic mutations, leading to neoplasia of the skin and ocular surface. As this condition is rare, only isolated case reports of XP with ocular surface squamous neoplasia (OSSN) are found in literature