Enfoque UTE

pp. 11-20

Authors: Martin Jamed Acosta Ruales, William Fernando Viera, Trevor Jackson, Wilson Vásquez Castillo

The Andean blackberry crop (Rubus glaucus) is very important for the farmers, since they must implement cultural practices that allow reducing the use of synthetic pesticides. The objective of the study was to evaluate the effect of different technological alternatives for the control of Botrytis sp. in the blackberry crop. The treatments were: 1: Absolute control (silwet+water), 2: Traditional chemical treatment (Carbendazim), 3: Mirtaceae extract (Iridium®), 4: Bacterial metabolite (Balus®) and 5: Trichoderma spp. (Tricomix®). The applications were carried out every 15 days for the synthetic product and every 8 days for the biologicals, organic and the control. A randomized complete block design (RCBD) was used with 3 repetitions and Tukey test at 5 % were made. The studied variables were botrytis incidence (%), yield (g/plot), weight (g), polar and equatorial diameter (mm), firmness (N), total soluble solids (Brix), titratable acidity (% citric acid) and pH (log H+). Throughout a weekly incidence analysis, it was possibly to identify that the Carbendazim, Trichoderma spp. and mirtaceae extract had a better control in the incidence of Botrytis sp. in the blackberry fruit.

pp. 29-46

Authors: William Quitiaquez, Isaac Simbaña, César A. Isaza-Roldán, Patricio Quitiaquez, César Nieto-Londoño, Fernando Toapanta-Ramos

The investigation purpose is to elaborate a detailed review about previous published investigations with direct-expansion solar-assisted heat pumps (DX-SAHP) used for water heating, in the last years. The growing energy consumption, the using of refrigerants that weaken the ozone layer, the greenhouse gases emission to the atmosphere and the global warming effect are the main problems that the conventional water heating systems present. Using hydrocarbons as refrigerants represents a pollution reduction and it is also the best option to replace hydrochlorofluorocarbons and chlorofluorocarbons, due to their low values of global warming potential and ozone depletion potential, close to 0. A DX-SAHP system takes advantage of the thermal solar energy directly by using a bare flat-plate solar collector. These systems provide domestic hot water over 50 °C and heating water volumes until 200 liters reaching COP values higher than 4. Solar energy and the using of alternative refrigerants with a low environmental impact are proposed to reach this purpose.

pp. 58-70

Authors: Ricardo Gonzalo Moreira Macías, Héctor Rodríguez, Eduardo Héctor-Ardisana, Carlos Feicán-Mejía, Saúl Anibal Mestanza Velasco, William Viera Arroyo

Soursop (Annona muricata L.) germplasm, from the central region of the Ecuadorian littoral, has diverse phenotypic characteristics, which have been little studied. The main objective of this research was to characterize in situ the morphological variability of 60 accessions of soursop. The morphological traits were evaluated using 20 quantitative and 10 qualitative variables of the plant and the fruit. Multivariate statistical methods were used as principal components, hierarchical conglomerate aggregation, discriminant and correlation analysis (Pearson) were performed. Descriptive analysis such as central tendency and dispersion (coefficient of variation, range, mean and standard deviation) were determined for the quantitative data; while frequencies were calculated for qualitative data. In terms of morphological traits, 74 % of the total variability was explained by the fourth component. Three conglomerates of similarity were formed, in which the height, diameter of canopy and fruit number per tree, were the characters of greater contribution for its conformation.

pp. 85-94

Authors: Víctor Muñoz Paz, Víctor Longa Cuayla, Alejandra Carreño Arispe, José Aguilar Franco

In this project a treatment system for the effluents of a leather tanning process was designed. This system was evaluated based on laboratory tests to ensure its viability, and the treatment was validated by analyzing effluents from the plant already installed. The system has three units: the first one is a Pretreatment that allows the oxidation of sulphides for the liming and draught baths, as well as the precipitation of chromium for the leather tanning baths; the second one is a Physical-Chemical Treatment for the general effluents of the process that allows to obtain treated effluents and decanted solids; the third is a sludge treatment that allows to obtain conditioned and low volume sludge to be collected for final disposal. The analysis of treated effluents showed a considerable reduction in the concentration of polluting chemicals that allows reusing the water and brings the company closer to compliance with the maximum levels allowed.

pp. 109-120

Authors: Lenin Quiñones Huatangari, Luis Ochoa Toledo, Nicolás Kemper Valverde, Oscar Gamarra Torres, José Bazán Correa, Jorge Delgado Soto

The artificial neural network (RNA) is a computational model that emulates the biological neural system in information processing. The originating models are suitable for the purpose of describing long-term specifics, in addition to nonlinear relationships. This tool is used to predict physical chemical and microbiological parameters that influence water quality. The United States National Sanitation Foundation proposed a water quality index, known as the NSF WQI. This article describes the design, training and use of the three-layer neural perceptron neural model for the calculation of the NSF WQI of the Utcubamba River and its tributaries. Using the Matlab software and applying the Levenberg-Marquardt training algorithm, the optimal RNA architecture was found to be 6-12-1, plus the percentage for the training, validation, and test sets of 70 %, 10 %, and 20 % respectively. RNA performance has been evaluated using the root of the root mean square error (RMSE) and the correlation coefficient (R). High correlations (greater than 0.94) were made between the measured and predicted values. Finally, the RNA proposal offers a useful alternative for the calculation and prediction of the water quality index in relation to dissolved oxygen (DO), biochemical demand for oxygen (BOD), nitrates, fecal coliforms, potential for hydrogen ions (pH) and turbidity.