New data on the settling velocity of artificial sediments and natural sands at high concentrations are presented. The data are compared with a widely used semiempirical Richardson and Zaki equation (Trans. Inst. Chem. Eng. 32 (1954) 35), which gives an accurate measure of the reduction in velocity as a function of concentration and an experimentally determined empirical power n. Here, a simple ...

A method for shortening of the settling time in all digital phase-locked loops is proposed. The method utilizes self monitoring to obtain the parameters necessary for feed-forward compensation. Analysis shows that by employing this technique both fast settling and good stability can be achieved simultaneously. Matlab and Verilog-AMS simulation shows that typical settling speed can be reduced to...

ferritin is a macromolecule and is responsible for the long term iron storage function in human serum and plasma. recent studies have highlighted the role of cell phone exposure on central nervous system, immune function and reproduction. the aim of this study was to investigate whether the human serum ferritin level could be interfered by the exposure to the 900 mhz gsm cell phones. fifty huma...

Two groups of aggregates with fractal dimensions of 1.81 ( 0.09 and 2.33 ( 0.07 were generated by coagulation of latex microspheres (2.84 μm) in a Jar-test (paddle-mixing) device. The collision rates between these fractal aggregates (200-1000 μm) and small (1.48 μm) particles were measured for individual aggregates that had settled through a suspension of the small particles. Aggregate permeabi...

1389 with u(w; s) = jwj1u(^ w; s) where ^ w = w=jwj1. For any w 2 R 2 and s 2 f0; 1g; jz(w;s)j 1 6jwj 1. We now turn our attention to signals w(k) 2 l n 1 and w(t) 2 L n 1 , and to distinguish them from vectors in R n we will use boldface type.

Aerobic activated sludge granules are dense, spherical biofilms which can strongly improve purification efficiency and sludge settling in wastewater treatment processes. In this study, the structure and development of different granule types were analyzed. Biofilm samples originated from lab-scale sequencing batch reactors which were operated with malthouse, brewery, and artificial wastewater. ...

Continuous homogeneous controllers are utilized in a full state feedback setting for the uniform finite time stabilization of a perturbed double integrator in the presence of uniformly decaying piecewise continuous disturbances. Semiglobal strong C1 Lyapunov functions are identified to establish uniform asymptotic stability of the closed-loop planar system. Uniform finite time stability is then...

This paper deals with the design ripple-free deadbeat controllers for sampled-data systems. Given a prescribed settling time, the design problem is tackled by computing a ripple-free deadbeat controller that optimizes an H2 performance criterion. This criterion accounts for the quality of the tracking response and for the control energy necessary to achieve the deadbeat behavior. Our main resul...

This paper presents results of a series of experiments on the settling velocity of spheres in twocomponent solid-liquid suspensions. Particular emphasis has been given to the effective values of density and viscosity of the mixture which allows us to describe the settling of the spheres in the mixture using appropriate modifications of the equations valid for the settling of spheres in pure flu...