Operational optimisation of water supply networks using a fuzzy system

This paper presents a fuzzy system to control the pressure in a water distribution network, by using valves and controlling the rotor speed of the pumping systems. The variable frequency drive tracks the minimum head of the pumping system, while the control valves have the function of eliminating the excess pressure at various points of the network. The control system can track any reference pressure value and there is no limit for the number of monitored points. Experiments were carried out to demonstrate the fuzzy system’s efficiency. By extrapolating the results achieved in the experimental setup to a real hydraulic network with leakages and no pressure control, the volumetric losses could be reduced by more than 56%. The experiments showed that the system is robust enough to control the pressure of an experimental setup of water distribution. Besides, the proposed system can be easily applied to similar water supply systems and would help to reduce the consumption of water and electricity, as well as to reduce the maintenance costs

The Gly972Arg polymorphism in insulin receptor substrate-1 is associated with decreased birth weight in a population-based sample of Brazilian newborns

OBJECTIVE - We studied the association between the Gly972Arg polymorphism in insulin receptor substrate-1 (IRS-1) and birth weight in a population-based sample of Brazilian newborns. RESEARCH DESIGN AND METHODS - We studied 194 newborn children with adequate gestational age to identify the association between the Gly972Arg polymorphism and birth weight using PCR-restriction fragment length polymorphism analysis. RESULTS - The data showed that the birth weight was lower in the newborns with the Gly972Arg polymorphism in IRS-1 compared with control subjects (3.1+1 +/- 31.8 vs 3.373 +/- 80.3 g. P < 0.008). The results also showed that the frequency of this polymorphism was increased in newborns with a birth weight <3,000 g (P = 0.041). CONCLUSIONS - These results suggest that the genotype Gly972Arg may influence birth weight, reinforcing the hypothesis that genetically determined insulin resistance and/or reduced insulin secretion can result in impaired insulin-mediated growth in the fetus.25355055