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1
tesis de grado
Publicado 2023
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Compañías mineras están en búsqueda constante de nuevas tecnologías para aumentar su productividad. Una de las tecnologías que les permite realizar la reconstrucción de la superficie sin poner en riesgo la vida de sus trabajadores es el uso de sensores LiDAR junto con plataformas móviles que les permiten rotar el sensor para realizar un escaneo completo de la estructura. Sin embargo, el procesamiento de los datos se realiza a través de ordenadores situados fuera de la mina, debido a su alto coste computacional, lo que se traduce en un alto coste de tiempo. En esta tesis presento como objetivo principal el diseño de un algoritmo paralelo para la fusión de nubes de puntos capturadas por un LiDAR y la reconstrucción de la superficie en tiempo real, con el fin de reducir el tiempo de procesado, teniendo en cuenta información a priori del patrón de barrido de los puntos. En la l...
2
artículo
Publicado 2021
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The intensive use of agrochemicals for food production in developing countries has generated a problem of environmental concern since many of these substances, which are usually difficult to biodegrade, can reach natural sources, generating their contamination. That is why the search for new technologies for the elimination of these pollutants has arisen with great interest. Advanced oxidation processes (AOP), whose main characteristic is the generation of highly oxidizing species such as the hydroxyl radical, can achieve the chemical modification of the pollutant, generating by-products that can be less harmful to the environment. In this work, the degradation of methomyl, a highly used insecticide in the Arequipa region, Peru, was evaluated using different PAOs such as ozonation in alkaline medium, UV-C/H2O2 and photo-Fenton processes at acid pH in natural surface waters. The effect of...
3
tesis de grado
Publicado 2023
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Compañías mineras están en búsqueda constante de nuevas tecnologías para aumentar su productividad. Una de las tecnologías que les permite realizar la reconstrucción de la superficie sin poner en riesgo la vida de sus trabajadores es el uso de sensores LiDAR junto con plataformas móviles que les permiten rotar el sensor para realizar un escaneo completo de la estructura. Sin embargo, el procesamiento de los datos se realiza a través de ordenadores situados fuera de la mina, debido a su alto coste computacional, lo que se traduce en un alto coste de tiempo. En esta tesis presento como objetivo principal el diseño de un algoritmo paralelo para la fusión de nubes de puntos capturadas por un LiDAR y la reconstrucción de la superficie en tiempo real, con el fin de reducir el tiempo de procesado, teniendo en cuenta información a priori del patrón de barrido de los puntos. En la l...
4
artículo
Publicado 2018
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El objetivo de este estudio fue determinar la eficiencia de un sistema computacional para el pintado de superficies planas frente al sistema tradicional (pintado a mano). El método utilizado definió los aspectos más significativos de los procesos de automatización del pintado de superficies planas en la Provincia de Coronel Portillo, así como el análisis económico de los procesos, tiempos, calidad y su relación técnico económico. El diseño utilizado fue el cuasi experimental transversal, que se realizó con un profesional experto con 5 años de experiencia en el proceso de pintado para asegurar el conocimiento experto frente al sistema computacional, sometiéndolos a una hoja de trabajo obtenida mediante el método de lluvias de ideas (se le aplicó la prueba de Alfa de Cronbach para medir la fiabilidad de la escala de medida). Para estimar se hizo uso de la estad...
5
artículo
Publicado 2018
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El objetivo de este estudio fue determinar la e?ciencia de un sistema computacional para el pintado de super?cies planas frente al sistema tradicional (pintado a mano). El método utilizado de?nió los aspectos más signi?cativos de los procesos de automatización del pintado de super?cies planas en la Provincia de Coronel Portillo, así como el análisis económico de los procesos, tiempos, calidad y su relación técnico económico. El diseño utilizado fue el cuasi experimental transversal, que se realizó con un profesional experto con 5 años de experiencia en el proceso de pintado para asegurar el conocimiento experto frente al sistema computacional, sometiéndolos a una hoja de trabajo obtenida mediante el método de lluvias de ideas (se le aplicó la prueba de Alfa de Cronbach para medir la ?abilidad de la escala de medida). Para estimar se hizo uso de la estadística infer...
6
artículo
The coffee industry, coffee shops and restaurants are in constant expansion and growth. Consequently, large amounts of Spent Coffee Grounds (SCG) are generated, which are solid coffee residues obtained after the ground coffee leaching process. This residue can be reused because of its compounds as phenolics. The objective of the present study was to evaluate the effect of extraction time (30-90 min) assisted by ultrasound (45kHz and 50 W), liquid-solid ratio (10-40 ml/g) and ethanol concentration (20-93.8%) in the total phenolic compounds (CFT) content expressed as mg gallic acid/g SCG dry matter. Surface response methodology (MSR) was used, as an efficient technique that minimizes the number of experiments, through the central rotational compound design (DCCR) to determine the effect of these 3 factors and to perform the optimization of the extraction process conditions of total phenoli...
7
artículo
The coffee industry, coffee shops and restaurants are in constant expansion and growth. Consequently, large amounts of Spent Coffee Grounds (SCG) are generated, which are solid coffee residues obtained after the ground coffee leaching process. This residue can be reused because of its compounds as phenolics. The objective of the present study was to evaluate the effect of extraction time (30-90 min) assisted by ultrasound (45kHz and 50 W), liquid-solid ratio (10-40 ml/g) and ethanol concentration (20-93.8%) in the total phenolic compounds (CFT) content expressed as mg gallic acid/g SCG dry matter. Surface response methodology (MSR) was used, as an efficient technique that minimizes the number of experiments, through the central rotational compound design (DCCR) to determine the effect of these 3 factors and to perform the optimization of the extraction process conditions of total phenoli...
8
artículo
The coffee industry, coffee shops and restaurants are in constant expansion and growth. Consequently, large amounts of Spent Coffee Grounds (SCG) are generated, which are solid coffee residues obtained after the ground coffee leaching process. This residue can be reused because of its compounds as phenolics. The objective of the present study was to evaluate the effect of extraction time (30-90 min) assisted by ultrasound (45kHz and 50 W), liquid-solid ratio (10-40 ml/g) and ethanol concentration (20-93.8%) in the total phenolic compounds (CFT) content expressed as mg gallic acid/g SCG dry matter. Surface response methodology (MSR) was used, as an efficient technique that minimizes the number of experiments, through the central rotational compound design (DCCR) to determine the effect of these 3 factors and to perform the optimization of the extraction process conditions of total phenoli...
9
artículo
The coffee industry, coffee shops and restaurants are in constant expansion and growth. Consequently, large amounts of Spent Coffee Grounds (SCG) are generated, which are solid coffee residues obtained after the ground coffee leaching process. This residue can be reused because of its compounds as phenolics. The objective of the present study was to evaluate the effect of extraction time (30-90 min) assisted by ultrasound (45kHz and 50 W), liquid-solid ratio (10-40 ml/g) and ethanol concentration (20-93.8%) in the total phenolic compounds (CFT) content expressed as mg gallic acid/g SCG dry matter. Surface response methodology (MSR) was used, as an efficient technique that minimizes the number of experiments, through the central rotational compound design (DCCR) to determine the effect of these 3 factors and to perform the optimization of the extraction process conditions of total phenoli...
10
artículo
Publicado 2015
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This paper shows that it is possible to estimate, from a single interferogram image, the error of the concave shape for an optically polished surface that will be used as a mirror in a reflecting telescope. In the Optics Laboratory of the PUCP, a Twyman-Green interferometer has been implemented; surface images with overlapping interference fringes known as interferograms are acquired. Algorithms based on Fourier transform allows the reconstruction of the surface shape and its deviation from ideal concave shape. Images were evaluated for different numbers of interference fringes in the same surface; in each case, a single image was necessary to determine surface error with the added advantage of not having contact with the surface.
11
artículo
Publicado 2020
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The processing parameters that maximize the pulp yield and the stability of the ungurahui nectar were evaluated by means of the Taguchi and Response Surface methodologies. The raw material used came from the town of Yurimaguas, Loreto Region - Peru, and was subjected to weighing, selection, classification, washing, disinfecting, maturing, pulping, refining, filtering, standardized (to formulate the nectar), pasteurized, packed, cooled and stored processes. In the first stage the parameters of maturation and pulping were obtained (T°: 51,99 °C, time: 1,74 h, fruit harvested: water in maturation (1: 3), ripened fruit: water in the pulped (1: 0,75)), which optimized the yield (37,33%) of ungurahui pulp. In the second stage the standardized parameters were determined (pulp: water (1: 1,33), percentage of gums: xanthan (0,02 %), arabica (0,03 %), carboxymethylcellulose (0,06 %) and lecithin...
12
objeto de conferencia
Publicado 2017
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Aunque las señales electromiográficas superficiales son la señal de entrada más común para los algoritmos de aprendizaje automático en aplicaciones de reconocimiento de gestos de la mano y estimación de la fuerza del dedo, sólo hay unos pocos sistemas disponibles comercialmente para la adquisición de EMG superficial. Este trabajo propone una matriz de electrodos superficiales seca, barata y fácil de fabricar. Este sistema utiliza múltiples sensores diferenciales activos integrados en una pequeña placa de circuito impreso de doble capa, cada uno de los cuales utiliza dos pequeñas áreas rectangulares de la capa inferior como capa conductora para la adquisición de la señal. Con una ganancia diferencial de 60dB entre 23 y 3000Hz y una relación de rechazo de modo común de -60dB a 60Hz. Se presentan los criterios de diseño y las simulaciones.
13
artículo
Publicado 2020
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Optimization of the steam quinoa cooking process was carried out, using a response surface design (RSM) 3-level: 3k factorial, and the multiple response optimization methodology of the desirability function (Dx) was used to find the optimal region, which are improved tools to optimize the variables of a process, evaluate the maximization of the water absorption index (WAI), water solubility index (WSI), degree of gelatinization (GE) and the minimization of cotyledon detachment (DC) of quinoa (Chenopodium quinoa Willd). The equipment used was a vertical cook with a steam generator, the study cooking variables, the steam pressure, and the cooking time. The optimal process values were: Pressure 1.5 kgf.cm-2 and time 8 minutes for the best characteristics of cooked quinoa WSI of 26.411%, WAI of 7.960 (g.g-1), GE of 89.245% and CD of 18.40%, the value of the desirability function as an indica...
14
artículo
Publicado 2020
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Optimization of the steam quinoa cooking process was carried out, using a response surface design (RSM) 3-level: 3k factorial, and the multiple response optimization methodology of the desirability function (Dx) was used to find the optimal region, which are improved tools to optimize the variables of a process, evaluate the maximization of the water absorption index (WAI), water solubility index (WSI), degree of gelatinization (GE) and the minimization of cotyledon detachment (DC) of quinoa (Chenopodium quinoa Willd). The equipment used was a vertical cook with a steam generator, the study cooking variables, the steam pressure, and the cooking time. The optimal process values were: Pressure 1.5 kgf.cm-2 and time 8 minutes for the best characteristics of cooked quinoa WSI of 26.411%, WAI of 7.960 (g.g-1), GE of 89.245% and CD of 18.40%, the value of the desirability function as an indica...
15
artículo
The aim of this study was to analyze the chemical composition and surface topography of commercially pure titanium implants, obtained from three trademarks frequently used in dentistry. There were nine titanium implants of the following systems: As Technology, Neodent and Sistema Nacional de Implantes. These materials were divided into three groups, with three implants in each group. Photoelectron Spectroscopy Excited by X-ray (XPS) was used to determine the chemical composition, while to characterize the surface topography we used Scanning Electron Microscopy (SEM). Titanium, carbon, silicon and oxygen were identified in all samples analyzed. Other contaminants were: silicon, aluminum, sulfur, lead, phosphorus, calcium, sodium and nitrogen. We identified impurities on the surface of all implants analyzed. We consider necessary to development more studies relating the presence and concen...
16
artículo
The aim of this study was to analyze the chemical composition and surface topography of commercially pure titanium implants, obtained from three trademarks frequently used in dentistry. There were nine titanium implants of the following systems: As Technology, Neodent and Sistema Nacional de Implantes. These materials were divided into three groups, with three implants in each group. Photoelectron Spectroscopy Excited by X-ray (XPS) was used to determine the chemical composition, while to characterize the surface topography we used Scanning Electron Microscopy (SEM). Titanium, carbon, silicon and oxygen were identified in all samples analyzed. Other contaminants were: silicon, aluminum, sulfur, lead, phosphorus, calcium, sodium and nitrogen. We identified impurities on the surface of all implants analyzed. We consider necessary to development more studies relating the presence and concen...
17
artículo
In the present work, the realism of the superficial wind simulations carried out with the model is evaluated emph Weather Research and Forecasting (WRF) is evaluated, with data obtained from the QuikSCAT (Quick Scatterometer) satellite. The meridional and zonal speeds of the wind are used as comparison parameters, as well as the stresses produced on the surface of the water. The knowledge of the configuration of the wind on the oceanic surface is important because it generates processes such as the upwelling, the spiral and the Ekman pumping. The intensity with which these processes are carried out determines the diversity and biological and shing richness of a region. The behavior of the wind is analyzed in terms of its horizontal speeds, the effort produced by these speeds, which determine the drag on a free surface and the rotational wind. Correlations greater than 0.6 are obtained in...
18
artículo
Publicado 2020
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The preparation in the formation of self-assembled monolayers on silicon surfaces has allowed us the technological advancement of new organic semiconductor materials, obtaining devices that stand out for their electrical properties at the nanometric scale1. For this investigation, the reaction between alkenes and hydrogenated surface of Si (100) was considered to form self-assembled organic monolayers2. The organic molecules of alkenes used were 1-dodecene, 1-tetradecene, 1-hexadecene and 1-octadecene, which stand out for the functionalization process of these organic films. For the treatment of the silicon surface, a previous hydrogenation3,4 reaction was considered, obtaining Si-H functional groups on the surface. Regarding, the formation reaction of the organic monolayer, the silicon substrate of the hydrogenated surface reacted with each of the alkenes5 at 220°C for 2 hours. The exp...
19
artículo
Publicado 2018
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The objective of this research was to identify the functional groups that are responsible for the adsorption of Pb (II) on the treated hair residues of the enzymatic unhairing process of the tanneries. For this purpose was made the preparation of adsorbent, which consisted in washing hair residues in order to deliming and lower the pH of 12 to neutral, after which they were dried and was applied these the treatment of acid hydrolysis, at the end of which these were washed, dried and ground. Then the hairs treated with the Pb (II) solution were placed in agitation in a range of time and pH, for the study of adsorption isotherms and the kinetic study. At the end of which a chemical characterization was carried out through the FTIR analysis and the XRD analysis. Thus also a physical characterization with a SEM analysis, by means of two detectors of the equipment. These analyses were carried...
20
artículo
Publicado 2004
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Descriptions of environmental impact are necessary to predict the effects of specific projects on defined and often small areas, as is the case of the bay of Chancay. In this bay residual water from the fish industry and urban spilling are usually discharged. Environmental impact caused on marine sediments is deduced from an evaluation of the bio-oceanographic conditions this bay presents. Impacts generated this way vary according the environmental variables sensitivity or fragility, thus it is, for example, that impact on whichever of them can put the rest of the trophic chain in danger.Such is the case of this research, environmental impact is produced on the short-run and takes place when fishing industrial processing plants are working. The one on the long-run takes place due to the gathering of residues and pollutants that can become irreversible or unavoidable as time goes. The i...
