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Temperature field forecast in concrete dam with the use of ARIMA models and the finite element method
This article describes a forecasting method, with the application of statistical models Auto-Regressive Integrated Moving Average (ARIMA) and a heat conduction model to forecast the temperature field in a buttress block of Itaipu dam. Monthly temperature series in 2010-2014 of surface thermometers to block were fitted with cubic splines and the series, now daily, were used as inputs for specific ARIMA models to produce forecasts as outputs. These outputs were used as boundary conditions to the thermal model of the block and this solved by the Finite Element Method (FEM). Obtained thus predicted temperature fields of block. The error MAPE between the values obtained by MEF and the real, in a test point, (where is an internal thermometer) measured the performance of the forecast of ARIMA models, and this was satisfactory, achieving near 15%. The proposed method has an innovative character for thermal analysis structures, in particular in concrete dams
Poultry offal meal in broiler chicken feed
An outstanding feature of poultry production that provides animal protein yield for human feeding is its short production cycle. This characteristic has a linear relationship with waste production. Increasing the inclusion of this residue in diets in the near future is desirable in step with the growth of poultry production since it offers a better environmental and nutritional alternative to current methods. We evaluated the effects on the performance and carcass characteristics of broiler chickens produced by the inclusion of poultry offal meal (POM) in their feed. Treatments consisted of a control diet (corn, Zea mays and soybean, Glycine max) and four diets with inclusion of 30, 60, 90 and 120 g kg-1 of POM. The diets were formulated based on the level of digestible amino acid once categorized as isocalcic, isophosphoric, isosodic, isoenergetic and isonutritive for protein, methionine+cystine, lysine and threonine. The feed's electrolytes were corrected so that each diet had the same electrolytic balance. The variables analyzed were feed intake, weight gain, feed conversion ratio, body weight, carcass yield, chicken cut yield and abdominal fat. Feed intake was not affected by the quantities of POM added. The weight gain, feed conversion, carcass yield and noble cuts presented quadratic responses to the treatments. Abdominal fat increased linearly. The performance of the poultry, and carcass characteristics were maximized by the inclusion of 53 and 65 g kg-1, respectively, of POM in the diet, and the inclusion of 120 g kg-1 of POM provided greater disposition of abdominal fat