Tópicos Sugeridos dentro de su búsqueda.
Tópicos Sugeridos dentro de su búsqueda.
1
tesis de grado
Publicado 2024
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El estudio de la calidad del agua en embalses, lagos y costas es una actividad que utiliza principalmente vehículos marinos tripulados por humanos para obtener parámetros del sitio como temperatura, conductividad, salinidad, pH y otros. Esta tarea se facilita mediante el uso de vehículos no tripulados, que mejoran la calidad de los datos en áreas peligrosas y minimizan la exposición humana. Este trabajo presenta una nueva metodología basada en conceptos de ingeniería de sistemas y Arquitectura Híbrida de Control para un vehículo de superficie no tripulado (Unmanned Surface Vehicle - USV) de clase catamarán llamado EDSON-J, para actividades de monitoreo remoto de la calidad del agua con instrumentación de carga útil. Se consideraron como aspectos críticos en el desarrollo del proyecto, los requisitos, la gestión de riesgos, la flexibilidad del diseño, la descomposición ló...
2
artículo
Publicado 2021
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The work determined the medium control envelope surface to improve the thermal comfort of a house in the city of Huaraz - Peru, for which, two houses with the same design, but with different envelopes were compared, one existing with a typical minimum control construction and the other with an improved medium control envelope, which takes advantage of passive solar energy. The thermal calculation was performed by analyzing heat gains and heat losses. In conclusion, the proposed envelope surface substantially improved the thermal comfort of a dwelling in Huaraz; predicting that, with an overall thermal transmittance coefficient of 1.05 W/m2 °C, with the support of passive solar heating, an indoor temperature of 21 ± 1°C is achieved, where more than 90% of the occupants are satisfied. Keywords: Thermal envelope; average control; solar radiation.
3
artículo
Publicado 2021
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The work determined the medium control envelope surface to improve the thermal comfort of a house in the city of Huaraz - Peru, for which, two houses with the same design, but with different envelopes were compared, one existing with a typical minimum control construction and the other with an improved medium control envelope, which takes advantage of passive solar energy. The thermal calculation was performed by analyzing heat gains and heat losses. In conclusion, the proposed envelope surface substantially improved the thermal comfort of a dwelling in Huaraz; predicting that, with an overall thermal transmittance coefficient of 1.05 W/m2 °C, with the support of passive solar heating, an indoor temperature of 21 ± 1°C is achieved, where more than 90% of the occupants are satisfied. Keywords: Thermal envelope; average control; solar radiation.
4
tesis de grado
Publicado 2022
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In Peru, constructions are commonly built with cement and bricks, then proceed to decorate and embellish the walls using texturing. Currently, in Peru, this process is done in a traditional way where generally support tools are used such as trowels, rollers, and brushes, among others. As this process is done manually, the texturing is of lower aesthetic quality. Due to its geographic location, Peru is one of the countries that most often applies cement in its constructions, which makes it the most accessible and suitable material for applying textures to walls. Currently, there is no specific machine for texturing, so the conceptual design of a lightweight machine for texturing on concrete surfaces was proposed using the VDI 2221 design methodology, integrating a variable speed control system and display of parameters in real-time.
5
tesis de grado
Esta investigación presenta el diseño y desarrollo de un robot para la recolección de sedimentos acuáticos superficiales en aguas someras. Su función principal es optimizar las técnicas tradicionales de muestreo y garantizar la precisión de los datos para la evaluación ambiental. El principio de funcionamiento del robot consiste en colocarlo manualmente en el punto de muestreo, donde desciende por su propio peso a través de la columna de agua hasta alcanzar el lecho de sedimentos. En este punto, emplea un innovador sistema de perforación que combina movimientos rotatorios y lineales, lo que permite que un recolector cónico recolecte muestras de los 52 mm superiores del sedimento, minimizando la pérdida de sedimentos finos. Construido principalmente con piezas impresas en 3D, el robot presenta un diseño modular en capas en su estructura mecánica, lo que facilita tanto el mon...
6
artículo
Publicado 2022
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Objectives: To evaluate the bending and topography properties of surface treated fiber posts. Material and Methods: Experimental, In vitro. The samples were divided into two groups, the flexibility of 40 fiberglass posts from 2 commercial houses was evaluated for each conditioning procedure P1: FGM White Post DC; P2: MAQUIRA Fiber Post. The conditioning techniques were: T1: control T2: Hydrofluoric Acid 10% 15 seconds T3: Hydrogen Peroxide 24% 60 seconds T4: aluminum oxide 50 µm and were subjected to the universal testing machine, for the bending test of 3 points. The topographic surface of the fiberglass posts was observed using a scanning electron microscope. Results: The deflection (mm) showed a significant difference comparing the control groups and the conditioned groups with an average maximum value of 0.59mm ±0.04 and a minimum value of 0.51mm ±0.06. In the maximum force (...
7
artículo
Publicado 2008
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Bonding failures of brackets and the repositioning of them occur quite often during the orthodontic treatment. Upon this situation, the professional may choose to stick the same bracket or bond a new one. The purpose of this study was to evaluate changes of the bonding strength of reconditioned brackets with direct flame, microetching and new brackets attached several times on the same tooth surface in vitro. 60 healthy human premolars extracted for orthodontic reasons were randomly assigned to 3 groups: Group I reconditioned brackets with air abrasion; Group II: reconditioned brackets with flame; Group III: new brackets. All brackets were bonded with resin No Mix (Prime Dental Manufactuing INC). Initially, new brackets were bonded to all groups to determine initial bonding strength (first shear test), then were subjected to four tests using a universal testing machine. The results showe...
8
artículo
Publicado 2008
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Bonding failures of brackets and the repositioning of them occur quite often during the orthodontic treatment. Upon this situation, the professional may choose to stick the same bracket or bond a new one. The purpose of this study was to evaluate changes of the bonding strength of reconditioned brackets with direct flame, microetching and new brackets attached several times on the same tooth surface in vitro. 60 healthy human premolars extracted for orthodontic reasons were randomly assigned to 3 groups: Group I reconditioned brackets with air abrasion; Group II: reconditioned brackets with flame; Group III: new brackets. All brackets were bonded with resin No Mix (Prime Dental Manufactuing INC). Initially, new brackets were bonded to all groups to determine initial bonding strength (first shear test), then were subjected to four tests using a universal testing machine. The results showe...
9
artículo
Publicado 2008
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The purpose of this study in vitro was to evaluate the tensille strength of adhesive system to the surface of bleached enamel with 10% carbamide peroxide with and without fluoride. We used nine healtly third molars, divided into three groups: Control (unbleached), group I (bleached with 10% Opalescence), group II (bleached with 10% Opalescence PF). Bleaching groups had a period of bleaching of 6 hours per day at 37°C, during 14 consecutive days; the teeth during this period were stored in artificial saliva. We waited 7 days to put a resin block (Filtek Z350,3M) of 5x5x3mm (w,l,h) on the buccal, palate or lingual surface of each tooth, previously we used 35% phosphoric acid (Scothbond, 3M) and an adhesive system (Single Bond 2, 3M). We used a diamond bioactive disc to make a horizontal and vertical cut to obtain the specimens, which were stored in distilled water. After 24 hours, the spe...
10
artículo
Publicado 2008
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The purpose of this study in vitro was to evaluate the tensille strength of adhesive system to the surface of bleached enamel with 10% carbamide peroxide with and without fluoride. We used nine healtly third molars, divided into three groups: Control (unbleached), group I (bleached with 10% Opalescence), group II (bleached with 10% Opalescence PF). Bleaching groups had a period of bleaching of 6 hours per day at 37°C, during 14 consecutive days; the teeth during this period were stored in artificial saliva. We waited 7 days to put a resin block (Filtek Z350,3M) of 5x5x3mm (w,l,h) on the buccal, palate or lingual surface of each tooth, previously we used 35% phosphoric acid (Scothbond, 3M) and an adhesive system (Single Bond 2, 3M). We used a diamond bioactive disc to make a horizontal and vertical cut to obtain the specimens, which were stored in distilled water. After 24 hours, the spe...
11
artículo
Publicado 2014
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Heavy metals are often found in sedimentary deposits as water pollutants. For this reason in this study was carried out the determination of heavy metals (Hg, Cd, Pb, Cr, Ni, Fe) in surface sediments in Water Bodies Canal del Dique, (artificial arm cupcake River) by smooth digestion method, using the methodology of Chester and Voutsinou, finding normal levels of these metals in these water bodies, despite having contributions of the Magdalena River, and to be influenced by mining areas. A slightly higher level of nickel was found in the Cienaga Grande de Lorica (site control, no anthropogenic sources of heavy metal pollution) relative to the other sampling points because it is a site rich in nickel, but their values are in permissible values, otherwise it is a good place to use as a control for the other metals, lead was not detected by the use of this methodology.
12
artículo
Publicado 2023
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Este estudio utilizó las propiedades hidrogeoquímicas de las aguas superficiales que rodean un proyecto minero en Perú, para compararlas con los estándares de calidad ambiental establecidos en el Decreto Supremo 004-2017-MINAM, centrándose en la categoría 3 para riego de vegetales y bebida para animales. Se evaluaron parámetros físico-químicos, inorgánicos, microbiológicos y parasitarios en lagunas y manantiales. Los resultados determinaron la presencia de depósitos ligeramente alcalinos con un pH de 9.59 y depósitos ligeramente ácidos con un pH de 5.33, así como depósitos con alto contenido de hierro, manganeso y zinc. Para garantizar la fiabilidad del análisis químico, se realizó un balance iónico de los principales cationes y aniones disueltos. El diagrama de Piper determinó la predominancia de aguas sulfatadas cálcicas, así como la presencia de un depósito de ...
13
artículo
This study focuses on designing and describing the operation of a fuzzy controller to regulate the speed of a direct current (DC) motor, widely used in spacecraft, defense machinery, robotics, electric trains, electric vehicles, and cranes. The article compares the results of the fuzzy controller with those of a proportional integral derivative (PID) controller, which was tuned using MATLAB tools. Transients of the motor speed curve, such as rise time, settling time, and overshoot, were measured. Regarding transients, the proposed fuzzy controller achieved better results than the PID controller tuned by MATLAB.
14
artículo
This study focuses on designing and describing the operation of a fuzzy controller to regulate the speed of a direct current (DC) motor, widely used in spacecraft, defense machinery, robotics, electric trains, electric vehicles, and cranes. The article compares the results of the fuzzy controller with those of a proportional integral derivative (PID) controller, which was tuned using MATLAB tools. Transients of the motor speed curve, such as rise time, settling time, and overshoot, were measured. Regarding transients, the proposed fuzzy controller achieved better results than the PID controller tuned by MATLAB.
15
artículo
Publicado 2018
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Nowadays, micromanipulation has an important role for assembly of micro-electromechanical components, because it enables to assemble very small components with different material properties and geometrical shapes in order to create complex multifunctional systems. Also, micromanipulation has contributed significantly in the field of medicine enabling manipulation of cells, molecules and bio-particles to study their behavior. Thus, a micromanipulation method that could move biological objects and microcomponents in an accurate, fast and multiple manner is needed. The preferred methods in the microscale are non-contact methods because they allow manipulating objects without damage or contamination. In this scope, microflows are very good candidates to drag micro-objects according to the flows direction and velocity, producing a drag force over the objects. In this research work, a study, t...
16
artículo
Publicado 2023
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The regulation of maritime autonomous surface ships (MASS) will need to redefine the traditional legal and conceptual categories of the law of the sea, whose rules were adopted over the basis that ships were manned by a master and crew on board.An evolutionary interpretation of UNCLOS allows to justifiy that the IMO endeavours to regulate the operation of MASS. Within this framework, the IMO has completed an exploratory study, in which it adopted a preliminary definition of autonomous ships and identified three high-priority themes: the meaning of the terms master, crew, or responsible person; the consideration of the remote-control station or centre; and the possibility to designate remote operators as seafarers. Subsequently, the IMO established in 2022 a workplan to adopt a goal-based non-mandatory MASS Code in 2024 and a mandatory Code in 2025.Following the exploratory study and the ...
17
artículo
Publicado 2019
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When we want to work with signals produced by the human body, we face different challenges that we must address, from the sensor to be used, through the conditioning of the signal for later registration and analysis, these stages are important to have a Good record of the clean interference signal that are foreign to the signal. One of the challenges you have when working with the electromyography signal, is to be able to understand the behavior of the muscles accompanied by the biophysics of the movement that is performed, for your better understanding and analysis the monitoring of several muscles at the same time is required, what originates a multichannel record, this condition is a complex requirement at the time of being able to design a team that can perform this multi record, being able to record these signals is vital for a subsequent analysis and understanding of muscle activit...
18
artículo
Publicado 1954
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An anesthetic technique for major abdominal surgery is described, which consists of liqht general anesthesia, combined with bilateral intercostal nerveblock from T6 to T11 blocks are performed just behind the midaxillary line on the unconscious patient. This technique proved to be particulary valuable for patients in very poor conditions, with is in agreement with previous experiences of other authors. The technique is easy to leam, and when some proficiency is acquired, the patient can be ready for incision within lo min, after begin of induction. For upper abdominal surgery we consider it the method of choice, with cyclopropane as the general anesthetic Using assisted or controlled respirations it provides good abdominal relaxation and a "quiet obdomen", while it seems to interfer with the patients physiology les s than other techniques. For pelvic surgery this combination is less sati...
19
artículo
Publicado 2025
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Thermotolerant coliform contamination in the surface waters of the Huaura River poses a significant risk to public health and natural ecosystems, both aquatic and terrestrial, highlighting the urgent need to implement sustainable treatments. The objective of this study was to evaluate the phytoremediation efficiency of the macrophytes Lemna minor and Eichhornia crassipes for the removal of thermotolerant coliforms from the surface waters of the Huaura River. Six prototypes of artificial aerobic lagoons with a retention time of 20 days were implemented, distributed in three experimental units for each species evaluated: Lemna minor (T1) and Eichhornia crassipes (T2). The initial biomass was 40 g/L in both macrophytes, including a control prototype without vegetation cover (T0). The results showed that both treatments with macrophytes achieved statistically significant removal (P < 0.05...
20
artículo
Publicado 2021
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Edible films were elaborated from gelatin solutions (4% w/v) of mahi-mahi skin (Coryphaena hippurus) with 2,5; 5; 7,5 and 10% v/v of oregano extract (OE) and its physicochemical, antimicrobial, structural and surface properties were determined. The control and with 2.5% OE films showed the lowest moisture and opacity values and the highest viscosity values. All films with OE inhibited the growth of Staphylococcus aureus and Proteus vulgaris. Alone films with 10% OE showed antimicrobial activity against all the strains evaluated. Scanning electron microscopy showed that the incorporation of oregano extract in the film-forming solutions, FFS, was related to an increase in the presence of oil droplets in the films, showing the lipid fraction of OE. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyzes showed the interaction between gelatin, pla...
