In a hydroelectric power plant or in a pumping station in order to avoid sudden large increase of pressure due to instantaneous valve closure sometimes a surge tank is installed. The height of surge tank is designed by the highest possible water level during the operation. The theoretical treatment of oscillation in a surge tank is difficult because of the non-linearity of friction term in the ...

An amicable pair for an elliptic curve E/Q is a pair of primes (p, q) of good reduction for E satisfying #Ẽp(Fp) = q and #Ẽq(Fq) = p. In this paper we study elliptic amicable pairs and analogously defined longer elliptic aliquot cycles. We show that there exist elliptic curves with arbitrarily long aliqout cycles, but that CM elliptic curves (with j 6= 0) have no aliqout cycles of length greate...

1 Description of the Model We consider a model of a water level control system extended from the one of Alur et al. [1] and our previous paper [4]. In particular, we use this case study to demonstrate the influence which different abstractions of the same continuous stochastic command have. The abstraction of a guarded command with a continuous probability distribution into one with a discrete ...

Abstract: Chemical storage tank leakage in petrochemical wharf is a serious economic, environmental and safety problem. Risk assessment is an effective way to identify chemical storage tank hazards and provides a guide for accident prevention in petrochemical wharf enterprises. Based on the characteristics of chemical storage tank zone, this paper proposes a real-time relative risk assessment m...

in this paper, analysis of fluid flow and heat transfer over the bank of tubes is considered. k-ω sst model is applied for simulation of turbulent flow. in this paper, the improvement of efficiency of a bundle of circular tubes by changing the shape of the cross section of one row of the pipes to the elliptical cross section as an innovative plan is considered. as know, friction factor in turbu...

a modified model has been analytically developed to describe the induction time of an elliptic air bubble in contact with an elliptic hydrophobic oil droplet. the role of hydrophobicity was revealed in the slippage of liquid over the surfaces of bubble and droplet. in this condition, the analytical relationships for pressure distribution and consequently hydrodynamic resistance force through th...

one of the main problems in micro irrigation system is inappropriate combination and in some cases inappropriate performance of filters and sand tanks in central control systems which cause reduction in efficiency of system and increasing of operating costs. this study evaluates affect the amount of algae on the performance of disc filters sand tank in research farm deputy of soil and water and...

Abstract—Eutrophication of surface water is one of the most widespread environmental problems at present. Large number of pilgrims and tourists visit sacred artificial tank known as “Brahma Sarover” located at Kurukshetra, India to take holy dip and perform religious ceremonies. The sources of pollutants include impurities in feed water, mass bathing, religious offerings and windblown particula...

PURPOSE In optical-CT, the use of a refractively matched polyurethane solid-tank in place of a fluid bath has the potential to greatly increase practical convenience, reduce cost, and possibly improve the efficacy of flood corrections. This work investigates the feasibility of solid-tank optical-CT imaging for 3D dosimetry through computer simulation. METHODS A matlab ray-tracing simulation p...

The paper deals with the study of SISO and MIMO processes using PID controller for a coupled tank process. The PID controllers have found wide acceptance and applications in the industries. In spite of their simple structures, PID controllers are proven to be sufficient for many practical control problems. This paper presents the PID controller design for controlling liquid level of coupled tan...