Enfoque UTE

pp. 42 - 54

Authors: Gabriela Cristina Chire-Fajardo, Milber Oswaldo Ureña-Peralta, S M García-Torres, R W Hartel

This research sought to optimize the mix of Peruvian cocoa beans and the cocoa content for the dark chocolate formulation, having as an optimization criterion the improvement of the physical properties of chocolate: color, particle size, rheological properties and texture, applying the response surface methodology. It was found that the optimal formulation presented a mixture of cocoa beans of 10 parts of CCN 51 plus 90 parts of ICS 6, dark chocolate at 70 % cocoa content, 29.6 % sugar and 0.4 % lecithin. Finally, the validation of physical properties reached 91.6 % on average.

pp. 30 - 41

Authors: Ana María Aveiga Ortiz, Patricio Noles, Aida de la Cruz, Fabián Peñarrieta, Francisco Alcántara

The objective of this work is to determine the physical-chemical variations in the water quality of Carrizal River (Manabí), in 21 sampling stations, covering an area of ​​51 km. Seven points were sampled in (i) the microbasin, 5 points in (ii) La Esperanza reservoir and 9 points in (iii) the sub-basin of Carrizal river. Samples were taken according to an experimental design of random blocks with factorial arrangement, and according to the results we show a correlation between the parameters and the different geographical positions monitored. Thus, we calculate a new water quality index called hardness index, which relates the alkalinity, oxide-reduction potential, hardness, conductivity, suspended solids, and total solids. According to this index, it is evident that, the concentration of minerals of calcium, magnesium, sulphates and carbonates, increased along with the concentration of solids in the water, as well as the REDOX potential and electrical conductivity, increased from the upper basin to the lower basin of Carrizal river. This correlation between physical-chemical parameters of the water and the different geographical positions monitored is probably influenced by anthropogenic activities.

pp. 13 - 29

Authors: Bryan Jhon Briceño-Martínez, Edilberto Antonio Llanes Cedeño, Juan Carlos Rocha-Hoyos, Edwin Chamba, Diego Cuasapud, Andrés Cárdenaz-Yánez

The objective of the study was to evaluate the 3D printing technologies made by Molded Deposition Modeling (FDM) and PolyJet from mechanical tests with Acrylonitrile Styrene Acrylate (ASA) and VeroWhitePlus RGD 835 materials, for the selection of the material and adequate technology in the manufacture of air ducts applied to automotive auto parts. To achieve the objective, mechanical tensile tests were carried out on specimens manufactured by both technologies, according to ASTM D638-14 for tensile tests and for bending tests according to ASTM 790; To evaluate the behavior of air flow in the pipeline, the air duct used in the Toyota Stout 2200 pick-up truck modeled by the Ansys Student software was selected as the case study. The results showed that the VeroWhitePlus RDG 835 material used in the construction of the duct by means of the PolyJet technology presented the best results with a yield strength of 4.7 MPa and a maximum bending stress of 28 MPa.

pp. 67 - 80

Authors: Dannyll Michellc Zambrano Zambrano, Darío Vélez, Yohanna Daza, José Manuel Palomares

This paper presents the social foraging behavior of Escherichia coli (E. Coli) bacteria based on Bacteria Foraging Optimization algorithms (BFOA) to find optimization and distributed control values. The search strategy for E. coli is very complex to express and the dynamics of the simulated chemotaxis stage in BFOA is analyzed with the help of a simple mathematical model. The methodology starts from a detailed analysis of the parameters of bacterial swimming and tumbling (C) and the probability of elimination and dispersion (Ped), then an adaptive variant of BFOA is proposed, in which the size of the chemotherapeutic step is adjusted according to the current suitability of a virtual bacterium. To evaluate the performance of the algorithm in obtaining optimal values, the resolution was applied to one of the benchmark functions, in this case the Ackley minimization function, a comparative analysis of the BFOA is then performed. The simulation results have shown the validity of the optimal values (minimum or maximum) obtained on a specific function for real world problems, with a function belonging to the benchmark group of optimization functions.