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One of the initial constraints of any dredging project is deciding where to place dredged material. When placed upland, materials can be used beneficially, as beach nourishment or for habitat restoration, or can be placed in an upland confined disposal facility (CDF). Several times the solids volume in water is required to fluidized and hydraulically pump the materials. Once in the CDF, materials settle out of suspension, with clarified water decanted. This paper describes in general a current weir design used by the U.S. Army Corps of Engineers (USACE) and illustrates the innovations of the new Jacksonville District standard weir. The new outfall structure is safer, easier to construct, and has inherent environmental protection features. It also has a longer life cycle and lower lifecycle cost than traditional structures. This paper also discusses a new composite weir system that is in the patent and construction phase. These new corrosion-resistant systems have the capability of revolutionizing and standardizing water control structures due to basic changes in material selection and operational controls. The construction, management, and maintenance of weir systems are a significant cost incurred by USACE navigation projects; improved systems are available that can reduce maintenance costs while improving the safety of personnel who operate them.

Among the electrocardiographic alterations used for stratifying the cardiovascular risk of life threatening arrhythmias (LFA) and sudden death (SD) there is the increment of the corrected QT(QTc). This increment is usually observable in obese patients (OP). Therefore, a study has been planned to investigate the possibility to predict QTc values in OP simply by detecting the best fitting regression method that represents the relationship between QTc and Body Mass Index (BMI). The study has been carried on 144 individuals classified as a function of their BMI in normoponderal subjects (NPS, No. 24; F/M=15/9; BMI=21.8± 1.7 kg/m(2)), Class I OP (No. 24; F/M=17/7; BMI=32.5± 1.1 kg/m(2)); Class II OP (No. 24; F/M=17/7; BMI=37.7± 1.5 kg/m(2)). Class IIIa (No. 24, F/M=15/9; BMI=44.4± 27 kg/m(2)), Class IIIb (No. 24; F/M=14/10; BMI 54.3± 2.7 kg/m(2)); Class IIIc (No. 24; F/M=14/10; BMI=63.3± 4.5 kg/m(2)). Both linear and non-linear fitting modes have been tested. While the BMI progressively increases in classified OP, the QTc shows an intergroup difference that is not only not constant but also declining in Class IIIc obesity. The optimal regressive model was found to be the following fourth order degree polynomial: QTc=317,15+(7,47xBMI)+(-0,28*BMI(2))+(0,005xBMI(3))+ (-0,00003xBMI(4)). By entering the BMI of a given OP into the above-cited formula, the QTc can be easily predicted and compared to that of NPS. Importantly, to have the possibility for a pre-electrocardiographic estimation of QTc allows all the medical and paramedical personnel, involved in the multidisciplinary treatment of obesity, to immediately establish the cardiovascular risk in the OP under observation