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Moisture and temperature are the main factors that affect the life expectancy of liquid-immersed power transformers. These factors speed up the aging process of cellulose insulation, worsening its physio-chemical properties and increasing the risk of faults in the transformer. Recently, a multi-physical modeling approach was reported aimed at estimating the temperature and moisture dynamics of transformer insulation for different loading conditions. The model objective was to evaluate how the moisture dynamics between oil and paper insulation might affect the loading capability of the transformer. Although the model is based on the representation and analysis of concrete regions of the oil–paper insulation, it could also be useful for the estimation of the moisture content of the solid insulation in moisture monitoring systems; however, the modeling had not been experimentally validated due to the difficulty of measuring the moisture in cellulose insulation during transformer operation. In this work, an experiment was designed and developed to carry out the experimental validation of the model and to evaluate the possibility of applying it for moisture monitoring purposes. Moisture dynamics experiments were carried out in an experimental test plant; the evolution of the moisture content throughout the experiment was assessed by direct measure and with dielectric response measurements. The experimental conditions were simulated with the model, and the estimated and measured moisture contents were compared. A detailed analysis was carried out to evaluate the precision of the model and to identify possible sources of error and improvements that may be implemented to improve its accuracy. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the quality of Tanzania grass (Panicum maximum) haylage with varying contents of dry matter (DM) and stored for 90 days. The quality of this grass was evaluated through the lens of a variety of physiochemical properties (e.g., chemical composition, aerobic stability, pH, microbial profile, etc.). A completely randomized design was used with four treatments (in natura, 400, 500, and 600 g kg-1 DM) and five replicates. Treatment with 600 g kg-1 DM yielded the highest DM haylage (p < 0.01) and soluble carbohydrate content (p < 0.01). Treatment in natura resulted in the highest O2 concentration inside the bales (p < 0.01), whereas treatments with 500 and 600 g kg-1 DM resulted in the highest CO2 values. The highest acetic acid concentrations of 36.4 ± 1.6, 38.2±1.6, and 48.9 ± 1.6 g kg-1 DM (p < 0.01) were observed post the in natura, 500 g kg-1 DM, and 600 g kg-1 DM treatments, respectively. Treatment with 600 g kg-1 DM yielded the highest pH value at hour zero (p < 0.01). Tanzania grass with 500 and 600 g kg-1 DM produced the highest quality haylage. [ABSTRACT FROM AUTHOR]

An important factor in hop growing is the process of drying. For this purpose belt dryers with follow-up conditioning are the most widespread but they are not ideal. In this respect, an analysis of the drying process was carried out in the belt dryer of Agrospol Velká Bystřice Co., Ltd. for the 'Saaz' hop variety. Drying parameters were monitored by means of fixed sensors, continuously sensing data loggers and samples taken for laboratory analysis (hop moisture, alpha and beta bitter acids, Hop Storage Index (HIS). The process of drying showed that hops are practically dry (10 ± 2.0% of moisture) already at the end of the second belt or possibly at the beginning of the third belt. It was also proved that hops are over-dried (moisture of 4 to 8%) and then they are adjusted by conditioning to the final moisture content of 8-10%. Excessive drying leads to cone disintegration, which makes any manipulation with hops for purposes of further processing difficult and results in greater losses of lupulin. [ABSTRACT FROM AUTHOR]

The live fuel moisture content is an important factor in estimating the risk of forest fires and their rate of spread. However, due to a lack of research, the FMC values in the Mediterranean region of Andalusia, Spain, must be obtained by sample collection. This study is therefore the first to provide tools for estimating the moisture content of the most widespread plant species in Andalusia. First, samples were collected to estimate the moisture content of the plants; these data were collected from May 2007 to the present. Each species has its own range of moistures that depend on the time of year and the physiological state in which they are found. Secondly, an extensive database was obtained for each day of sample collection from the nearest weather station with free access. The statistics are performed at 12 solar hours on the day of sample collection and 24 h before collection, and then at 7 days, 14 days, 1 month, 3 months and 6 months before the day of collection. Finally, this database was statistically analyzed in two ways: Multiple linear regressions and random forest for each species. The predictive capacity of random forest is superior (R2 > 0.89) to that obtained in linear regression (R2 < 0.86). The highest root mean square error obtained in the case of the random forest is 0.74479 while in the linear regressions it was 1.29184. Consequently, uncertainty regarding fire behavior in the case of forest fires is reduced. • Moisture samples collected from May 2007 to April 2021. • Substantial improvement of the estimates of LFMC through Random Forest. • LFMC is a fundamental variable for flammability and rate of fire spread. [ABSTRACT FROM AUTHOR]

Splitting or cracking of the outer skins reduces the garlic storage life-time and its marketability. To determine the parameters which affect the mechanical properties of garlic skin, white and pink bulbs were taken for this study. Bulbs were harvested in 3 stages, namely 10, 20 and 30 days after cutting off the irrigation. Bulbs were cured in shade at 23±1°C for 2, 9, 16 and 23 days. Then, dried skins were treated for 5 days at the ambient temperature of 23°C and relative humidity (RH) of 17%, 38%, 55%, 77% and 95%. The moisture content, thickness and strength, stiffness, stress and strain at breakage were measured. Results showed that at later harvesting and during curing, moisture content, thickness and burst pressure decreased. It was revealed that the multi-directional strength reached its maximum when the skin moisture content of white ecotype and pink cultivar reached 21.28% and 31.72%, respectively. The irrigation having been cut off, the skin strength reduced rapidly after 28 days for white ecotype and 18 days for pink cultivar. The skin strain increased and consequently stiffness decreased when moisture contents were higher than 20%. Moreover, moisture content, thickness, burst pressure and strain at breakage of skins increased with the increase of incubation in relative humidity while the stress and stiffness decreased. Furthermore, pink cultivar skins as compared to white skin were broken with less force easily. [ABSTRACT FROM AUTHOR]