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The use of sprinkling with ventilation to cool dairy cows is considered an appropriate practice to reduce the negative effects of heat stress. However, due to climate change, water will increasingly become a limited resource, so we need to make water use more and more efficient. For this purpose, an active drying sensor has been developed in order to time the sprinkling cooling system. The sensor reproduces the thermal response of a cow, considering both sensible and latent heat exchange, and is located in the feeding alley, about two meters above the floor. This allows the fabric of the sensor (simulating the fur) to be wetted by the sprinkler, and blown by the fan. The water content of the sensor fabric during the drying time is monitored by measuring its electrical conductivity, allowing the estimation of the time the fur becomes dry. Another two specifically designed instruments are presented, the first to estimate the fur’s water content after spraying, and the second to detect the time the fur became dry. Sensor output, interpreted through a simplified model, gave a predicted drying time with an error ranging between −11.4% and +14.8% (R2 = 0.789). In the commercial barn where the experiments were conducted, the use of the sensor allowed an estimated reduction in water consumption of about 57%, with respect to the fixed timing normally used. As a perspective, the sensor could be used to assess cows’ heat stress level.

Aim of study: To test new approaches to perform mechanical weeding inside the row in horticulture and tree fruit fields. The idea is to weed the row by skipping the crop by means of a rotating system instead of a traditional crosswise one. Area of study: North of Italy. Material and methods: Numerical models have been developed to simulate mechanical weeding over time by generating numerical maps to quantify the different kind of worked areas. Main results: Considering the efficiency of weed control on the row, the rotating plant-skipping system with vertical axis (RPSS-VA model) with two working tools gives the best performance index (1.1.RWA% = 95.9%). A similar performance can be obtained by the crosswise displacement plant-skipping system (CDSS model, 1.1.RWA% = 95.9 %), but with very high crosswise translation velocity (with va/vr ratio = 1/5, 1.1.RWA% = 94.5%). With regard to the outwards worked area the RPSS-VA models give the best performances (2.2.%OWAR index from 127.2% up to 282.3%). To reduce the worked area outside the row, the FBTS models give lower index (2.1.OWAR%), while the RPSS-HA works only on the row, but with the lower 1.1.RWA% index among all tested models (55.8%). Research highlights: Rotating systems resulted more efficient than traditional ones, and provide considerations on the use of electric drive power instead of hydraulic one. This study highlights also the need of new approaches in designing lighter working tools. Lastly, the proposed classification of the worked areas could be used as reference standard.

Questo lavoro discute alcuni elementi critici dell’attuale sistema tributario italiano, in particolare in relazione al principale prelievo, l’imposta personale sul reddito. Si sostiene che l’aver trascurato la necessaria relazione tra capacità contributiva e spesa pubblica ha contribuito, nel tempo, a spostare l’enfasi sulla funzione dell’imposta come strumento di riduzione delle disuguaglianze attraverso la progressività, piuttosto che come strumento per raggiungere un’adeguata ripartizione degli oneri della spesa pubblica. In questa prospettiva, si sostiene nel lavoro, il peso dell’Irpef appare sbilanciato soprattutto se posto in relazione all’Iva, della quale si propone una revisione volta a ricomporre il prelievo complessivo relativo ai due tributi. Si suggerisce, infine, una profonda revisione del sistema di finanza territoriale, che si caratterizza come propedeutica a qualsiasi tentativo di revisione del sistema tributario centrale., Argomenti, N. 17 (2020): settembre - dicembre