The aim of this study was to investigate the effectiveness of dried activated sludge (DAS) and mixed dried activated sludge with rice husk silica (DAS & RHS) for removal of hydrogen sulfide (H2S). Two laboratory-scale filter columns (packed one litter) were operated. Both systems were operated under different conditions of two parameters, namely different inlet gas concentrations and different ...

Pit latrines are the most frequently used sanitation systems in developing countries because of weak infrastructure and poor economic wealth. A modified ventilated improved pit latrine, with a biological filter beneath is proposed to stabilize and to remove the bulk of the nitrogen from the liquid phase. Although the hydraulic loading rate in the proposed biological filter system was calculated...

slow sand filters are as a proper technology for pre-treatment of raw water, with a fine and medium trubidity in small communities in developing countries. thus, with a minimum operation cost and minimum need for expest bodies have the maximum efficiency. the purpose of this research is carried out to evaluate the efficiency of two processes of horizontal flow roughing filter and vertical flow ...

This paper investigates the problem of single-channel noise reduction in the time domain. The objective is to find a lower dimensional filter that can yield a noise reduction performance as close as possible to or even better than that obtained by the full-rank solution. This is achieved in three steps. First, we transform the observation signal vector sequence, through a semi-orthogonal matrix...

The G-SL(AM)2 (or grasp-SLAM) problem is the analog of the well studied Simultaneous Localization and Mapping (SLAM) problem in the domain of grasping. The G-SL(AM)2 problem is to localize the object relative to the hand while simultaneously updating the system model and manipulating the object. Stick-slip friction and intermittent contact are fundamental aspects of grasping that lead to nonsmo...

— Let p be an odd prime, K a finite extension of Qp and G := Gal(Qp/K) the Galois group. We construct and study filtration structures associated torsion semi-stable representations of G. In particular, we prove that two semi-stable representations share the same p-adic Hodge-Tate type if they are congruent modulo pn with n > c′, where c′ is a constant only depending on K and the differences bet...

purpose : to offer a semi-automatic algorithm to determine the area of angiographic hyperfluorescence methods : the proposed algorithm included wavelet filter, histogram equalization and modified otsu thresholding. hyperfluorescent area of 30 angiographic images obtained from patients with leaking choroidal neovascularization (cnv) and diabetic retinopathy were evaluated and the results were co...

the $k$-th semi total point graph $r^k(g)$ of a graph $g$, is a graph obtained from $g$ by adding $k$ vertices corresponding to each edge and connecting them to endpoint of edge considered. in this paper, we obtain formulae for the resistance distance and kirchhoff index of $r^k(g)$.

In this note we present two proofs of Theorems A and B ; one proof uses differential forms, the other, which is somewhat more elementary, is based on differential geometry. Let then G be a real connected compact Lie group and assume that the fundamental group of G is infinite. We have to prove that G is not semi-simple. We note that for compact groups "semi-simple" means that the center of G is...

ground water is the major source of drinking water in rural and semi-urban areas of assam. it contains an excessive amount of iron (1 to 10 mg/l). people living in rural and semi-urban areas of assam uses indigenous household iron filter units – developed using community prepared wooden charcoal (cpwc) and river sand (rs) as filter media. cpwc and rs processed and respectively termed as process...