Herein we report a multi-zone, heating, ventilation and air-conditioning (HVAC) control case study of an industrial plant responsible for cooling a hospital surgery center. The adopted approach to guaranteeing thermal comfort and reducing electrical energy consumption is based on a statistical non-parametric, non-linear regression technique named Gaussian processes. Our study aimed at assessing the suitability of the aforementioned technique to learning the building dynamics and yielding models for our model predictive control (MPC) scheme. Experimental results gathered while the building was under regular use showcase the final controller performance while subject to a number of measured and unmeasured disturbances. Finally, we provide readers with practical details and recommendations on how to manage the computational complexity of the on-line optimization problem and obtain high-quality solutions from solvers.

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Lemongrass essential oil (LEO) has been evaluated as a silage additive to improve silage fermentation and reduce fermentative losses. The present study aimed to evaluate the effects of increasing levels of LEO on whole-plant sorghum silage (WPSS) fermentation profile, fermentation losses, chemical composition, dry matter (DM) and neutral detergent fibre (NDF) in vitro degradation and aerobic stability. Five cultivars and fifty experimental silos were used to evaluate the following LEO levels: 0, 1, 2, 3 and 4 ml kg−1 DM of WPSS. The material was compacted (650 kg m−2) and the silos were sealed, weighed and stored at room temperature for 167 days. The addition of LEO linearly decreased butyric acid content and the ratio between lactic and acetic acids. Intermediate levels of LEO increased NH3-N and reduced lactic and acetic acids content. LEO linearly decreased silage gas losses. However, LEO did not affect total silage losses and DM recovery. Intermediate levels of LEO addition decreased organic matter and crude protein in the WPSS. The addition of LEO did not affect other chemical composition parameters, DM and NDF in vitro degradation, and pH and temperature of the silage after aerobic exposure. Thus, LEO supply in WPSS reduces gas losses, butyric acid concentration, and the ratio between lactic and acetic acids. However, LEO does not improve the chemical composition, in vitro degradation, and aerobic stability of WPSS.

The objective of this study was to evaluate the gas and effluent losses and the chemical composition of Brachiaria brizantha cv. Piatã with inclusion of bean residue. The inclusion of 0, 10, 20 and 30% of bean residue in Brachiaria grass silage were evaluated in a completely randomized design with five replicates. The results were submitted to analysis of variance and regression, tested by the Tukey test at 5% probability. An increase (P<0,05) of 4,494 percentage units was observed for each 1% inclusion on dry matter recovery. There was a reduction (P<0,05) of 0,259; 0,72 and 0,722 percentage units for each 1% of bean residue on the pH values, losses by gases and effluent, respectively. An increase (P<0,05) of 0,093 was observed; 0,046; 0,191 and 0,031 percentage units for each 1% of the residue added on dry matter, mineral matter, crude protein and ether extract. There was a reduction (P<0,05) of 0,046; 0,233; 0,136 and 0,091 percentage units for each 1% of residue added on organic matter, neutral detergent fiber, acid detergent fiber and hemicellulose.The inclusion of 10% of bean residue in the piatã silage is enough to reduce gas and effluent losses, increase dry matter recovery and improve the chemical composition of the silage.

Sugarcane has a high yield potential; however, ensiling has been a challenge, and its fibre has low quality for ruminant feed. This study aimed to evaluate increasing levels of a fibrolytic enzymatic blend (300 U xylanase + 300 U cellulase/g) during sugarcane ensiling on fermentative profile, losses, chemical composition, in vitro degradation, and aerobic stability. Forty silos were assigned to four treatments: 0, 200, 400 and 600 mg enzymatic blend/kg sugarcane fresh matter. The trial was performed in a randomised blocked design, in which five sugarcane cultivars were defined as blocks. Silos were performed in 15-L PVC tubes and stored at room temperature for 45 days. Enzyme level did not affect silage pH, ammonia-N, soluble carbohydrates, ethanol, or organic acid concentration. Although increasing enzyme levels linearly increased effluent losses, there was no effect on gas losses or dry matter recovery. Treatment had no effect on silage chemical composition, in vitro degradation, or silage pH after aerobic exposure. However, enzyme treatment quadratically affected silage temperature after aerobic exposure and aerobic stability period. Intermediate levels of enzymes increased silage temperature after aerobic exposure and reduced the aerobic stability period. Therefore, addition of enzymes during sugarcane ensiling shows no effect on silage fermentation, nutritional value or dry matter recovery, but linearly increases effluent losses. Although an intermediate level of enzymes decreases aerobic stability, it has no effect on silage pH after aerobic exposure.