Visualização de formas geométricas ornamentadas em árvores urbanas

In this article, we present qualitative research in case of study type, aiming to analyze how participants in a workshop taught by the author in an international event visualize spatial geometric shapes, over ornamented trees (cypresses) in front of housing in an urbanized city in southern Brazil, based on the researcher's photographic records. We had 29 participants, who filled a Google Forms at the beginning of the work as a strategy to motivate them to the activity. Images that resemble the ellipsoid, paraboloid, and cone were proposed for the participants to answer if they perceived geometric shapes in such objects that were ornamented by man, giving them formats that the researcher considers involve Geometry. In addition, they were asked to provide a short justification for their choices. Results show that the participants (who come from different levels of higher education and institutions) had difficulties perceiving 3D shapes, mainly being limited to 2D shapes. In addition, the terminologies used did not always follow those that are mathematically employed, including some that are inappropriate. We can conclude that it is necessary to develop perceptions and geometric thought skills.En este artículo, se presenta una investigación cualitativa, de tipo estudio de caso que tuvo como objetivo analizar cómo los participantes de un taller ofrecido por el autor en un evento internacional, visualizan formas geométricas espaciales encontradas en árboles ornamentales (cipreses) frente a viviendas en una ciudad urbanizada del sur de Brasil, a partir de los registros fotográficos del investigador. Participaron 29 sujetos, quienes respondieron a un formulario en Google Forms, al inicio del trabajo, como una forma de motivarlos para hacer las tareas. Se propusieron imágenes que se asemejan a elipsoides, paraboloides y conos, para que los participantes respondieran si percibían formas geométricas en tales objetos, que fueron ornamentados por el hombre, asignándoles formatos que el investigador considera que están involucrados con la Geometría. Además, se les pidió que dieran una pequeña justificación para sus elecciones. Los resultados mostraron que los participantes, de diferentes niveles de educación superior y de diferentes instituciones, tenían gran dificultad para percibir formas 3D, mostrándose mayormente limitados a formas 2D. Además, las nomenclaturas utilizadas no siempre siguen las que se emplean matemáticamente, incluyendo algunas que son inapropiadas. Se concluye que es necesario desarrollar percepciones y habilidades que faciliten el desarrollo del pensamiento geométrico.Neste artigo, apresenta-se uma pesquisa qualitativa, em um estudo de caso, que teve por objetivo analisar como participantes de uma oficina ministrada pelo autor, em um evento internacional, visualizam formas geométricas espaciais encontradas em árvores (ciprestes) ornamentadas à frente de moradias em uma cidade urbanizada no sul do Brasil, a partir de registros fotográficos do pesquisador. Participaram 29 sujeitos, os quais responderam a um formulário no Google Forms, no início dos trabalhos, como uma forma de motivá-los para a sequência das atividades. Foram propostas imagens que se assemelhavam a elipsoides, a paraboloides e a cones, para que os participantes respondessem se percebiam formas geométricas em tais objetos, que foram ornamentados pelo homem, dando-lhes formatos que o investigador percebeu envolver Geometria. Além disso, solicitava-se que apresentassem uma pequena justificativa para suas escolhas. Os resultados mostraram que os participantes, de diversos níveis de ensino superior e de variadas instituições, apresentaram grande dificuldade em perceber formas 3D, limitando-se, em maioria, a formas 2D. Além disso, as nomenclaturas empregadas nem sempre seguiram aquelas que são matematicamente empregadas, incluindo algumas que são inapropriadas. Conclui-se ser necessário desenvolver percepções e habilidades que proporcionem o desenvolvimento de pensamento geométrico

Fault detection algorithm for telephone systems using the danger theory

Orientador: Fernando Jose Von ZubenDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Essa dissertação apresenta um algoritmo de detecção de falhas composto de múltiplos módulos interconectados e operando de acordo com o paradigma suportado pela Teoria do Perigo em imunologia. Esse algoritmo busca atingir características significativas que um sistema de detecção de falhas deve expressar ao monitorar um sistema telefônico. Essas características seriam basicamente a adaptabilidade, devido à forte variação que esse sistema pode ter em seus parâmetros ao longo do tempo, e a diminuição no número de falsos positivos que podem ser gerados ao se classificar como falha toda anormalidade encontrada. Cenários simulados foram concebidos para validar a proposta, sendo que os resultados obtidos foram analisados e comparados com propostas alternativasAbstract: Abstract This thesis presents a fault detection algorithm composed of multiple interconnected modules, and operating according to the paradigm supported by the Danger Theory in immunology. This algorithm attempts to achieve significant features that a fault detection system is supposed to express when monitoring a telephone system. These features would basically be adaptability, due to the strong variation that operational conditions may exhibit over time, and the decrease in the number of false positives, which can be generated when any abnormal behavior is erroneously classified as being a fault. Simulated scenarios have been conceived to validate the proposal, and the obtained results are then analyzed and compared with alternative proposalsMestradoEngenharia de ComputaçãoMestre em Engenharia Elétric

Análise multi-critério aplicada ao mapeamento da suscetibilidade a escorregamentos

This paper presents the application of a multi-criteria analysis (MCA) tool for landslide susceptibility assessment in Porto Alegre municipality, southern Brazil. A knowledge driven approach was used, aiming to ensure an optimal use of the available information. The landslide conditioning factors considered were slope, lithology, fl ow accumulation and distance from lineaments. Standardization of these factors was done through fuzzy membership functions, and evaluation of their relative importance for landslide predisposition was supported by the analytic hierarchy process (AHP), based on local expert knowledge. Finally, factors were integrated in a GIS environment using the weighted linear combination (WLC) method. For validation, an inventory, including 107 landslide points recorded between 2007 and 2013 was used. Results indicated that 8.2% (39.40 km²) of the study area are highly and very highly susceptible to landslides. An overall accuracy of 95% was found, with an area under the receiver operating characteristic (ROC) curve of 0.960. Therefore, the resulting map can be regarded as useful for monitoring landslide-prone areas. Based on the fi ndings, it is concluded that the proposed method is eff ective for susceptibility assessment since it yielded meaningful results and does not require extensive input data.Este estudo apresenta a aplicação de uma ferramenta de análise multi-critério para mapear a suscetibilidade a escorregamentos no município de Porto Alegre, sul do Brasil. Uma abordagem guiada pelo conhecimento de especialistas foi utilizada, com o intuito de otimizar a utilização das informações disponíveis. Os fatores condicionantes dos escorregamentos considerados foram declividade, litologia, acúmulo defl uxo e distância de lineamentos. A padronização desses fatores foi realizada por meio da aplicação de funções fuzzy e a importância relativa de cada um na predisposição do terreno a escorregamentos foi estabelecida com o apoio da técnica AHP (Analytic Hierarchy Process), com base no conhecimento de especialistas locais. Por fi m, a integração dos fatores em ambiente SIG se deu por meio do método denominado Combinação Linear Ponderada (WLC). Para validar os resultados, utilizou-se um mapa inventário contendo 107 cicatrizes de escorregamentos, registradas entre 2007 e 2013. Os resultados indicam que 8,2% (39,38 km²) da área de estudo possui uma suscetibilidade alta e muito alta a escorregamentos. A validação dos resultados obteve uma exatidão geral de 95%, com uma área abaixo da curva ROC (Receiver Operating Characteristic) de 0,960. Portanto, o mapa obtido pode ser considerado útil para monitorar as áreas propensas a esses processos. Com base nos resultados, conclui-se que o método proposto é efi caz para a avaliação da suscetibilidade, uma vez que os resultados obtidos são robustos e que não foi necessária uma quantidade extensa de dados de entrada

Innovative non-thermal technologies affecting potato tuber and fried potato quality

Background: Potatoes are important tubers for human consumption, providing an essential source of energy and great nutritional characteristics for human health. However, before consumption, potato tubers need to be stored and processed. As frying is the most common technique used in potato processing, fried potato is the most important processed potato product. Some food characteristics, provided by the frying process, are considered desirable, but others are harmful to human health and, thereby the main challenge is to reduce the formation of the undesirable characteristics, without compromising the sensorial attributes. Scope and approach: In this review, the origin, economic importance, morphology and composition of potato tubers are presented. Afterwards, some factors affecting potato tuber quality, not only for human consumption, but also for further processing are addressed. Then, potato processing is discussed with a focus on the frying process, including the textural, chemical and nutritional changes induced by frying and the main characteristics affecting the quality of fried potato products. Finally, a special focus is given to the novel emerging non-thermal technologies and a brief review of their effects on potato tuber and fried potato quality is provided. Key findings and conclusions: Irradiation, cold plasma, ultrasounds, pulsed electric fields and high pressure processing are innovative non-thermal technologies with potential to be an alternative for the traditional treatments of potato tubers and to be applied as a frying pre-treatment, improving time and energy for slicing and cooking, and creating improved and healthier fried potatoes. Further studies are needed to better understand the subjacent biochemical mechanisms.publishe

Homography-Based Tracking Control for Mobile Robots

This work presents a control strategy that allows a follower robot to track a target vehicle moving along an unknown trajectory with unknown velocity. It uses only artificial vision to establish both the robot’s position and orientation relative to the target. The control system is proved to be asymptotically stable at the equilibrium point, which corresponds to the navigation objective. Experimental results with two robots, a leader and a follower, are included to show the performance of the proposed vision-based tracking control system

Avaliação do potencial biotecnológico de Streptomyces isolados de processo de compostagem

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Analysis of the Conservation of Central American Mangroves Using the Phytosociological Method

Our study of mangrove swamps revealed a total of 120 species, of which 13 are characteristics of mangrove swamps, and 38 of flooded areas with low salt. All the others are invasive species which have taken advantage of the degradation of these natural ecosystems. The scenario is not very different in Laguna de Tres Palos in Mexico. The frequent fires in the low-growing semi-deciduous rainforest (dry forest) have caused intense erosion, with the consequence that the site has silted up. As a result, the first vegetation band of Rhizophora mangle is extremely rare. Instead, Laguncularia racemosa and Conocarpus erectus are dominant, along with a band of Phragmito-Magnocaricetea with a high occurrence of Phragmites australis (Cav.) Trin., which acts as an indicator of sediment silting. It is extremely frequent for several reasons: as it is the decrease of the salinity of the water, the scarce depth due to the accumulation of sediments and the contamination by the entrance of residual waters of the nearby populations. When the depth and salinity of the water are suitable, the dominant species are Rhizophora mangle, Laguncularia racemosa, and Avicennia germinans

Estudio de prefactibilidad para la instalación de una planta de producción de teclados mecánicos personalizables

Ante el gran auge de la industria del gaming, surge la demanda de una gran cantidad de equipos periféricos para poder jugar videojuegos, especialmente de los teclados mecánicos, debido a todos sus grandes beneficios. Frente a los altos precios ofrecidos por empresas extranjeras en el mercado local, y ante la gran demanda por este tipo de productos en el mercado, el contexto es el indicado para plantearse la posibilidad de poder implementar una planta de producción de teclados mecánicos personalizables, por lo que el presente documento se encarga de contestar la siguiente pregunta: ¿Cuál es la viabilidad técnica, de mercado, económica, financiera, social y medioambiental para la instalación de una planta de producción de teclados mecánicos personalizables? Luego de realizar el estudio de mercado, teniendo en cuenta como público objetivo a Personas dentro de Perú consideradas “gamers” que usen PC escritorio de rango de edad de entre 16 y 34 años de nivel socioeconómico AB, se calculó que la demanda del proyecto de prefactibilidad para la instalación de una planta de producción de teclados mecánicos personalizables es de 3199 teclados al año 2025. Acto seguido, se encontró como lugar idóneo para implementar la planta de producción el distrito de Lurín, en la ciudad de Lima. Además, se calculó que el tamaño de planta para la fabricación de teclados mecánicos es de 3150. Asimismo, se determinó que el proceso productivo ideal para la producción teclados mecánicos personalizables es el de ensamble bajo manufactura celular, y que la estructura de la organización para la planta de producción debería ser de tipo jerárquica. Finalmente, se concluyó que para implementar el proyecto es necesaria una inversión de S/300,486.08, de los cuales se financiará el 40%, mientras que el 60% será capital propio. El proyecto de instalación de la planta de producción de teclados mecánicos personalizables resulta ser rentable presentando un VAN financiero de S/ 1,230,055.52; y un TIR financiero de 222.41%, el cual es superior al COK del proyecto (19.19%).Given the boom of the gaming industry worldwide, there is a great demand for a large amount of peripheral equipment to play video games, especially mechanical keyboards, due to all the great benefits that this product offers. Faced with the high prices offered by foreign companies in the local market, and the high demand for this type of products in the market, the context is the right one to consider the possibility of implementing a production plant for customizable mechanical keyboards, so this document is responsible for answering the following question: What is the technical, market, economic, financial, social and environmental feasibility for the installation of a production plant for customizable mechanical keyboards? After conducting the market study, taking into account as a target audience people in Peru considered "gamers" who use desktop PCs between 16 and 34 years of age and socioeconomic level AB, it was calculated that the demand for the pre-feasibility project for the installation of a production plant for customizable mechanical keyboards is 3199 keyboards in 2025. The district of Lurín, in the city of Lima, was then found to be the ideal location to implement the production plant. In addition, it was calculated that the plant size for the manufacture of mechanical keyboards is 3150. It was also determined that the ideal production process for the production of customizable mechanical keyboards is assembly under cellular manufacturing, and that the organizational structure for the production plant should be hierarchical. Finally, it was concluded that an investment of S/300,486.08 is necessary to implement the project, of which 40% will be financed, while 60% will be equity capital. The project for the installation of the production plant for customizable mechanical keyboards is profitable, presenting a financial NPV of S/1,230,055.52; and a financial IRR of 222.41%, which is higher than the COK of the project (19.19%)

ESTUDIO REOLÓGICO DE LOS FLUIDOS VISCOELÁSTICOS SURFACTANTES UTILIZADOS EN OPERACIONES DE FRACTURAMIENTO HIDRÁULICO

Resumen Con el pasar de los años, la producción de los campos de petróleo muestra una tendencia a declinar debido a factores que se presentan en la operación de un campo, por esta razón es necesaria la implementación de técnicas de estimulación que ayuden a incrementar la producción de hidrocarburos, el cual es el objetivo principal de la industria.Entre muchas técnicas que se han probado con éxito, la más destacada es el fracturamiento hidráulico. Siendo una de las técnicas de estimulación de pozos en yacimientos de hidrocarburos, más utilizada; su finalidad es resolver problemas que se relacionan con la baja productividad, atribuida generalmente a daño inducido en la formación y/o baja permeabilidad del yacimiento. Esta técnica ha logrado estimular la producción de pozos de petróleo de una manera excepcional pues los logros alcanzados han superado en gran medida las expectativas de producción, razón por la cual continúa siendo una de las técnicas más usadas alrededor del mundo.Actualmente se han adelantado investigaciones que brindan información para optimizar esta técnica logrando la introducción a la industria del uso de fluidos llamados viscoelásticos surfactantesque en un principio fueron creados para limpieza de pozos pero que por sus características tanto físicas como químicas, además de su comportamiento, son usados como fluidos de fractura al igual que en otras operaciones de estimulación de pozos. Es importante destacar el uso de los VES para optimizar las operaciones de fracturamiento hidráulico, pues exhiben excelentes propiedades de transporte y soporte del material propante, siendo más compatibles con la formación, por cuanto su proceso de degradación no genera residuo algunomaximizando la permeabilidad retenida en el empaque de grava. En este artículo se presenta un estudio de las propiedades reológicas de los fluidos viscoelásticos surfactantes y cómo influyen en las operaciones de fracturamiento hidráulico. Palabras clave: fluidos viscoelásticos, fluidos VES, reología, fracturamiento hidráulico, fluido de fractura. Abstract. Over the years the production of oil fields have a tendency to decline due to factors that arise in the operation of a field, therefore it is necessary to implement stimulation techniques to help increase oil production, which is the main objective of the industry.Among many techniques that have been proved successfully, the most prominent is the hydraulic fracturing. As one of the well stimulation techniques in hydrocarbon reservoirs most used its purpose is to solve problems related to low productivity, usually attributed to damage induced in the formation and / or low permeability reservoir. This technique has been successful in stimulating oil production wells in an exceptional way because the achievements have greatly exceeded the expectations created by the engineers, for this reason is still one of the most common techniques used around the world.Currently have been developed research that will provide information to optimize this technique making the introduction into to the industry of the so-called viscoelastic fluids which, were originally created to clean wells but due to their physical and chemical characteristics as well as their behavior are used as fracture fluids in hydraulic fracturing operations and in other well stimulation operations. Importantly, the use of VES to optimize the technique mentioned above because it exhibits excellent transport properties and proppant material support, being more compatible with the formation, because its degradation process does not generate any waste and may return to the surface.This article presents a study of the rheological properties of viscoelastic surfactant fluids and how they influence the hydraulic fracturing operations. Keywords: viscoelastic fluids, VES fliuds, rheology, hydraulic fracturing, fracture fluid.