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In this work, basil plants were fertilized with 0, 2.5 mM and 10 mM nitrogen (with different NO3−/NH4+ ratios), and then monitored using a low-power technique based on an optical leaf meter and a low-cost RGB sensor interfaced with an Arduino UNO board. The study aimed to investigate possible relationships between the concentration of some plant compounds (i.e., leaf chlorophyll and flavonoids content) and the nitrogen balance index, with the output data of a low-cost RGB sensor to indicate its capability in discriminating among different levels of nutrition. The data obtained underwent univariate and multivariate analysis. The univariate data analysis showed that the low-cost RGB sensor readings followed the development of the plants according to the varying applications of nitrogen. The multivariate analysis of the data showed that the indices related to plant metabolic efficiency and leaf colour were those most affected by the nitrogen levels of the solutions used. The comparison of the discrimination powers of the systems showed that both systems achieved comparable discrimination performances (85.0% and 89.4%) for plants supplied with 0 mM nitrogen solution. However, at increasing levels of nitrogen, the RGB sensor performed worse than the optical leaf meter (− 15.8% and − 8.6% for the 2.5 and 10 mM N treatments). The effect of the NO3−/NH4+ ratio could hardly be distinguished (except for the total chlorophyll resulting from the optical leaf meter readings). More data is, however, necessary to create a more robust model for future implementation of the application of such a sensor.

Driving on ice is still a risky activity. Research has investigated the factors contributing to the friction mechanism and has reported experimental studies of pneumatic tyres on ice in order to develop models that predict tractive and braking performance on ice/snow. Therefore, developing testing methods to obtain relevant experimental data for the validation of models is equally important. There are agricultural and industrial vehicles which are also designed for pulling but there are no specific studies reporting experimental tests on traction force of such machines in snowy conditions. However, this issue is very topical, as demonstrated by the appearance on the market of winter tyres for such vehicles. This study presents a method for testing winter tyres in outdoor test facilities with a focus on traction performance. The conclusions will serve in future investigations as a concise knowledge source to develop improved testing facilities and tyre–ice interaction models, aiding the development of better tyre designs and improved vehicle safety systems. The functional tests hereafter described have been carried out with the aim of evaluating the possibility of measuring the influences of different technique solutions on the performance of certain 17.5 R25 sized industrial tyres.

The precise monitoring of the inner microclimate of a greenhouse implies an increase of the production costs following the expensive needed sensor arrays. Currently, there is availability of low-cost sensors and cards for data storage and processing, but their application in real scale facilities is still under study. This research aimed to find a solution to manage and implement the outcome of various information (i.e. luminosity as well as air humidity and temperature) on the internal environment of a tunnel greenhouse to point out the most critical dynamics occurring during the growth cycle of basil plants in summer. Placing low-cost sensors inside a tunnel greenhouse made it possible to acquire data with an adequate rate (0.1 min−1) and spatiotemporal distribution throughout the facility. Data storage and processing took place thanks to an on purpose created weather station based on Arduino Yun Rev2 board. The highest variability of air temperature and moisture inside the greenhouse occurred when the solar radiation begins to heat the cover of the greenhouse (between 6.00 and 7.00 AM) and few hours after the maximum peak of solar radiation (843.4 ± 133.3 W/m2). Low-cost sensors combined with spatial fitting of the data provided insights about the effective microenvironmental conditions occurring on daily basis. This, implemented with IoT technologies, will be the base for the realization of economic monitoring systems.

Value-at-risk (VaR), expected shortfall (ES), and similar risk measures are based on knowledge of the underlying probability distribution of portfolio value, and in particular its lower tail. The theory is well developed for the familiar normal/lognormal case, but it is well known that the normal does not match the actual returns observed on portfolios of stocks and other risky assets. Empirical distributions tend to have fatter tails and negative skewness. Two standard ways to deal with this problem are either to assume the returns are generated by a probability law with more flexibility about tail shape than the Gaussian, such as one of the Johnson family of distributions, or else to develop an empirical fit to the unknown density using a technique such as Gram–Charlier or Cornish–Fisher approximation. In both approaches, the density is chosen to match the moments of the empirical density from the data. In this article, the author follows the second approach but suggests that a better approximation can ...

Different mixtures of olive pomace (OP), olive mill wastewater (OMWW) and olive pruning residues (OPR) were aerobically co-composted under natural conditions. Compost temperature showed a sharp increase in the first 40-60 days, followed by a stabilization at 60°C and a decline after 150 days, whereas compost water content ranged from 50-55% to 25-30%. Total and selec-tive microbial counts were followed throughout the experiment by means of innovative (IMT) and conventional (CMT) microbiological techniques. Pseudomonas spp., anaerobic bacteria, actino-mycetes, and fungi reached levels of 8, 7, 5 and 6 log CFU g–1 compost, respectively, with a slight depression after 30-80 days. Total and fecal coliforms strongly decreased during the com-posting process. The use of IMT allowed to de-tect a higher and more stable growth of micro-organisms if compared to CMT. IMT was dem-onstrated to be an appropriate and reliable method for monitoring the microbial pools dur-ing the co-composting process.

The aims of this work are to assess the persistence of rotenone in oil and drupes of olive plants of cultivars Nocellara del Belice (NB) and Cassanese (CA), and to compare the quality of oils from rotenone-treated and untreated plants. Samples of drupes and oil were analyzed at 2, 12, 22 and 30 days after treatment. Rotenone levels in drupes of treated plants declined by about 50% after 22 days from treatment (0.037 mg kg(-1) in NB and 0.039 mg kg(-1) in CA), whereas the respective values in the oil were higher (0.209 mg kg(-1) in NB and 0.229 mg kg(-1) in CA) and had a lower decay half-life (4.02 days in NB and 4.71 days in CA). For both cultivars, no significant differences in oil physicochemical and nutritional parameters were found between the two treatments. The panel test of oils extracted after 22 days did not reveal significant differences in unpleasant aromatic notes nor defects between the two treatments. Our results confirm that serious doubts remain about the safety and healthiness of oils extracted from drupes treated with rotenone. This information could assess the real risk in the use of this product for plant protection in olive growing.

From 1997 to 2000 a nutrition experiment was conducted to test the effects, on olive trees (cv.Carolea), of different fertilizers quantities and application methods. The fertilization to soil was made once, at bud break in spring, whereas foliar treatments were repeated four times: before flowering; after fruit set; at pit hardening and at the end of summer, before veraison. Parameters determined include the following: growth rate; percentages of flower bud differentiation; percentages of ovary abortion; fruit set; summer fruit drop and yield at harvest. In order to evaluate the nutritional status of trees, samples of leaves were analysed in April, July and November From the first two years, the trees fertilized with foliar sprays showed an increase in vegetative parameters and yield. From the third year, applications of only foliar fertilizers gave worse results than the fertilization to soil, demonstrating the necessity of fertilizer application to roots. The foliar application of macro-elements increased the productivity of trees, both as an addition to the fertilization to soil and, to a lesser extent, as alternative to it. This suggests that foliar fertilization can be used as a cheap and viable alternative for olive production.

Among the Mediterranean countries, Italy results to be the second after the Spain for the olive and olive oil production (FAOSTAT, 2012), with around 1.2 million of olive grove hectares, by 80% displaced in the Italian southern regions (ISTAT, 2010). In the olive oil industry, the oil extraction is carried out in oil mills, which are classified in pressure mills, and in continuous “two” or “three” phases way mills. In all milling typologies, only not over the 20% of processed olives constitute the oil production, while the milling byproducts, wastewater and pomace, represents up to 120% of processed olives. These wastes could constitute a problem for their sustainable disposal as well as a resource for soil C stabilization and sequestration, energy generation or production of value-add compounds for the food, pharmaceutical or cosmetic industries.

The addition of organic matter in the form of compost improves overall physical, chemical and biological properties of soils but, to be really sustainable, the composting process should be carried out using the by-products available in situ. Two different soils of a Mediterranean olive orchard, one managed traditionally (NAS) and the other amended with compost (AS), were investigated in a two-year experiment. Increases in total organic matter, total nitrogen and pH, were detected in AS if compared to NAS. Significant increases in total and specific microbial counts were observed in AS, with a clear amelioration of microbiological soil quality. The results demonstrated that soil amendment using compost deriving from olive mill by-products can be an important agricultural practice for supporting and stimulating soil microorganisms and, at the same time, for re-using these byproducts, so avoiding their negative environmental impact.

Edgeworth binomial trees were applied to price contingent claims when the underlying return distribution is skewed and leptokurtic, but with the limitation of working only for a limited set of skewness and kurtosis values. Recently, Johnson binomial trees were introduced to accommodate any skewness-kurtosis pair, but with the drawback of numerical convergence issues in some cases. Both techniques may suffer from non-exact matching of the moments of distribution of returns. A solution to this limitation is proposed here based on a new technique employing Hermite polynomials to match exactly the required moments. Several numerical examples illustrate the superior performance of the Hermite polynomials technique to price European and American options in the context of jump-diffusion and stochastic volatility frameworks and options with underlying asset given by the sum of two lognormally distributed random variables.