MOMEN AKUMULASI DARI SUATU ANUITAS AWAL DENGAN TINGKAT BUNGA ACAK
This article discusses the three moments formed from the accumulation of due annuity with random interest rate. The highest moment of these three moments is obtained by first determining the previous two moments. Moment accumulation is used to predict the accumulation of profits expected by investors from an investment made during n periods.
Annuities Under Random Rates of Interest II
Some attempts were made to evaluate the future value (FV) of the expected value and the variance for various cash flows (CF). The motivation stemmed from some recursive formulas. This method does not apply directly to the evaluation of present values (PV). One can get some estimates for the PV using results about the FV. We will present a direct approach to evaluate the PV of both factors for some CF. It will turn to be similar to that used to evaluate the FV. Furthermore it makes it possible to study the PV of these CF directly, and may suggest a method to study some other CF as well.
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.