Adaptive System Identication Based on All Pass/Minimum Phase System Decomposition 1
In this paper we present a novel adaptive IIR digital lter composed of a cascade of an all-pass lter and a minimum- phase lter. The coecien ts of the lter are updated in such a way as to achieve minimum mean-squared error between the output of the unknown system and the output of the digital lter. Computer simulation veries that the digital lter coecien ts converge to the unknown system coecien ts in the case where the system is com- posed of a cascade of all-pass section and minimum phase section. Keywords | system identication, adaptive lters.
An adaptive IIR digital filter based on estimation of allpass and minimum-phase system
In this paper, a new infinite impulse response (IIR) adaptive digital filter (ADF) which is composed of a cascade block of allpass system and a block of minimum-phase system connected in series is proposed. The allpass section is implemented using a series connection of second order allpass systems, while the minimum phase system has all its poles at the origin. The coefficients are updated using a simplified version of the LMS algorithm. By considering the unknown system to be having the same structure as that of the adaptive digital filter, it is proven that the poles of the ADF converges to the poles of the unknown system when the input is a stationary white signal. Computer simulation confirms our analysis.
Parboiled rice effluent: A wastewater niche for microalgae and cyanobacteria with growth coupled to comprehensive remediation and phosphorus biofertilization
Abstract The potential of microalgae and cyanobacteria for bioremediation of wastewater by nutrient uptake combined with simultaneous biomass production is a well recognized perception of today's world. The present study illustrates the treatment of a highly polluted wastewater generated during parboiling of paddy in rice mill industries, widely operational in developing countries where rice is the staple food crop, with the help of microalgal and cyanobacterial isolates capable of growing at high rates in parboiled rice mill effluent (RME). This endeavor leads to comprehensive bioremediation of the said effluent and subsequent use of the harvested biomass as slow release phosphorus biofertilizers and the treated effluent for crop irrigation. The RME-acclimatized algal consortium demonstrated highest growth in terms of fresh weight and greatest remediation efficiency at the end of 36 days' treatment of RME, with 93.9% phosphorus and 100% ammonia-nitrogen removal, 98.7%, 91.6% and 93.5% reduction in biological oxygen demand, chemical oxygen demand and total dissolved solid, respectively, and an increment of 186 ± 0.3 mg L − 1 dissolved oxygen, bringing down the pollutants level well below the discharge limits suggested by Central Pollution Control Board, India. Additionally, microalgae in the consortium aggregated in clumps spontaneously in presence of the filaments of Phormidium sp. facilitating easy harvest. The RME-acclimatized algal consortium demonstrated highest accumulation of polyphosphate (poly-P) (0.76 ± 0.01% of dry weight) as well as highest release of phosphorus in non-sterile soil emphasizing the essential role of soil phosphorus solubilizing organisms to leach soluble phosphorus from the insoluble poly-P present in the biomass. The rice seedlings watered with treated RME also showed improved growth effect on shoot height and leaf width. The study results establish the suitability of RME as an excellent growth media for microalgae and cyanobacteria.