El agua es un compuesto químico muy estable, formado por átomos de hidrogeno y oxígeno, de formula H2O. El agua es inolora, insípida e incolora, y su enorme presencia en la Tierra (el 71 % de esta se encuentra cubierta de agua) determina en buena parte la existencia de vida en nuestro planeta. En la minería, al igual que en otro tipo de actividades, el uso del agua es 100 % necesario, esto mejora las labores mineras y la explotación de los minerales, ya que la minería es una de las actividades que más contaminan el ambiente, incluso, el agua no se salva de la misma. La siguiente encuesta tiene como fin conocer la opinión de la sociedad sobre que tanto conocimiento tiene sobre el uso del agua en la minería y, a partir de estos resultados, hacer un análisis que nos permita determinar si se puede hacer unos talleres de información sobre este tema.

In this paper, we obtained and characterized a composite film made of lead zirconate titanate (PZT) piezoelectric ceramic and nonpolar polyvinylidene fluoride (α-PVDF) as a functional material. The scanning electron microscopy results show this composite film to have mixed connectivity due to the agglomeration of some of the PZT particles. The response of the composite to an applied ac voltage at 4110 Hz has a slope of 0.074 nm/V. The measured displacement is in the range of 0-30 nm for electric voltages ranging from 0 to 400 V. The experimental results show the composite performance as an acoustic emission sensor to be in good agreement with the response of a commercial standard microphone in the frequency range of 2-6 kHz. By applying 2 kN of cyclic force at a frequency of 3 Hz, we obtained an 80-V peak signal and calculated a dissipated power equal to 158 μW. Index Terms-Lead zirconate titanate (PZT), non-polar polyvinylidene fluoride (α-PVDF).Ricardo Luiz Barros de Freitas received the B.Sc. degree in computer engineering from the School of Engineering of Lins in 2005 and the M.Sc. and Ph.D. degrees in electrical engineering from UNESP-São Paulo State University, Ilha Solteira, Brazil, in 2008 and 2012, respectively. He joined the UNESP Optimization Group, Ilha Solteira with a CNPq PDJ grant (2015), as a Post-Doctoral Researcher. He has experience in electrical engineering, computer engineering, and biomedical engineering. He is currently an Adjunct Professor Doctor with the Department of Electrical Engineering and collaborator of the Master's Program in electrical engineering and computing with UNIOESTE-CECE-Campus Foz do Iguaçu. His research interests are knowledge optimization, intelligent materials, piezoelectricity, electronic instrumentation, structured programming, microcontrollers, sensors, hardware, software, and artificial neural networks.

Resistive sensor arrays (RSAs) have been developed for a variety of applications depending on resolution requirements, active sensor area, and cost. Composite-based piezoresistive sensors are commonly found in RSAs. However, they present an intrinsic problem related to the parasitic current paths that flow through the whole composite, which cause a crosstalk effect. Various circuits have been proposed to reduce the crosstalk effect in sensor arrays. In this paper, we compare a number of readout circuits with PSpice models, mainly those including voltage feedback (VF) circuits and zero potential (ZP) circuits. To develop an array with 3600 sensors using a piezoresistive composite, we selected the improved isolated drive feedback circuit (IIDFC). Using nodal analysis, we were able to develop an alternative mathematical circuit model, which allowed us to identify its unique characteristics, including the influence of array size on the crosstalk effect and the restriction on minimal impedance that the array elements must attain to maintain a minimum error. In a resistive array with 3600 sensors and a sensor range of 10-100 k , we obtained an absolute error of less than 3.56%. In addition, the proposed mathematical circuit model obtained a maximum absolute error difference of 0.03% when compared with the PSpice model with the precision operational amplifier OPA37. Thus, using the IIDFC circuit and considering the minimal allowable impedance, it is possible to maintain a reduced error in an RSA with a large number of sensors.

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