SILVA FILHO, E. M. Uma Proposta de Aplicação de Webquests No Processo de Ensino e Aprendizagem de Física. 2016. 89 f. Dissertação (Mestrado Nacional Profissional em Ensino de Física) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2016. / Submitted by francisco lima (admir@ufc.br) on 2017-06-29T13:49:21Z No. of bitstreams: 1 2016_dis_emsf.pdf: 3707083 bytes, checksum: 2df242365bbc55245c388ea213c6f5a2 (MD5) / Approved for entry into archive by Amélia Barrocas (barrocas.amelia@gmail.com) on 2017-06-29T14:37:13Z (GMT) No. of bitstreams: 1 2016_dis_emsf.pdf: 3707083 bytes, checksum: 2df242365bbc55245c388ea213c6f5a2 (MD5) / Made available in DSpace on 2017-06-29T14:37:13Z (GMT). No. of bitstreams: 1 2016_dis_emsf.pdf: 3707083 bytes, checksum: 2df242365bbc55245c388ea213c6f5a2 (MD5) Previous issue date: 2016 / This work aims to analyze the use of technological resources WebQuest in physics classes, in order to verify their behavior as a facilitating tool in the learning process. Given the presence of technological resources, such as computer and Internet in the daily lives of all, it is proposed a teaching method based on this exchange between the classroom of physics and the use of virtual tools. To develop this proposal, a survey was conducted among 131 students of College of the Military Police of Ceará, one of the most prestigious schools in the state public network of Ceará; this research addressed the demand for the inclusion of new technologies in the daily physics classes for high school and primary school. The interviewed students showed interest and excitement in the activities carried out with the WebQuest methodology, because until then, these resources were not used in physics classes. The proposed solution led to the use of dynamic and interactive technology tools in class. / Este trabalho acadêmico tem como objetivo analisar a utilização do recurso tecnológico WebQuest em aulas de Física, com o desígnio de verificar o seu comportamento como ferramenta facilitadora no processo de aprendizagem. Tendo em vista a abarcante presença de recursos tecnológicos, como computador e Internet, no cotidiano de todos, é proposta uma metodologia de ensino baseada nesse intercâmbio entre a Física da sala de aula e o uso de ferramentas virtuais. Para desenvolver essa proposta, foi realizado um levantamento entre 131 alunos do Colégio da Polícia militar do Ceará, uma das mais conceituadas escolas da rede pública estadual do Ceará; nesse levantamento foi abordada a demanda da inclusão das novas tecnologias no cotidiano escolar das aulas de Física para algumas turmas de ensino médio e fundamental. Os alunos entrevistados mostraram interesse e empolgação pela atividade realizada na metodologia com a WebQuest, pois, até então, não havia a praxe da utilização deste recurso nas aulas de Física, mas, para esse problema, a solução proposta levava a uma modificação na metodologia a ser utilizada durante as aulas, as quais passariam a ser contempladas pelo uso de ferramentas tecnológicas dinâmicas e interativas.

Los excedentes de butanos y pentanos de que dispondrá Venezuela es un gran incentivo para el desarrollo de nuevas tecnologías que permitan transformarlos en productos de mayor valor añadido por vías más ventajosas que las actualmente disponibles. De la revisión bibliográfica, surgió un catalizador a base de óxidos de vanadio y magnesio que permitía visualizar la posibilidad de desarrollar una tecnología novedosa para la producción de hidrocarburos no saturados por la vía de la deshidrogenación oxidativa. Para concretar el desarrollo de esta tecnología, se debería recurrir al uso de reactores de lecho fluidizado o móvil que permiten solventar el potencial explosivo de la mezcla hidrocarburos-oxígeno separando las zonas de oxidación del hidrocarburo de la de oxidación del catalizador, que además ofrecen la ventaja de un aumento sustancial en la selectividad. Como el catalizador disponible no reúne las características necesarias de resistencia a la atrición se propone resolver el problema agregándole un soporte adicional como sílice o alúmina, materiales ya ampliamente usados en reactores del tipo arriba mencionado. El objetivo central de este trabajo fue el de cubrir esta parte del conocimiento con el fin de poder optimizar las características del catalizador. Además, se consideró conveniente hacer un intento de mejorar el comportamiento de la fase activa mediante la incorporación de nuevos elementos, y de estudiar el comportamiento de los catalizadores más interesantes en la deshidrogenación oxidativa de n-pentano para así tener la posibilidad de evaluar el potencial de extensión de la tecnología.Para ello, se preparó una serie de catalizadores y se construyó un equipo que permitiera hacer las experiencias necesarias. A fin de poder dar una interpretación a los cambios de comportamiento que se observaron, hubo que proceder a caracterizar los catalizadores.Los resultados catalíticos obtenidos, corresponden a la DHOX de n-butano y luego al n-pentano. Analizando el efecto de los soportes y el de los promotores. El soporte más estudiado ha sido la sílice a fin cuantificar el efecto que tenía la naturaleza del soporte sobre la actividad y la selectividad, así como la relación Mg/V óptima o el éfecto de dilución del soporte. Se observó una disminución de la actividad, mientras que en lo referente a selectividad se observaron cambios en cuanto a la distribución de productos, pero con selectividades globales semejantes a la fase activa pura, hasta un contenido en sílice del 30%. Se encontró que el catalizador MV4-30 tiene características interesantes alrededor del cual, en un futuro pudiera desarrollarse la tecnología. Otros materiales soportados que se encontraron interesantes para futuros estudios fueron los catalizadores Gamma30 y el Alfa30.En lo que respecta a los promotores, sólo se estudiaron algunos (Sb, Bi, Mo y Ga) con resultados interesantes en cuanto a selectividad. Se aprovechó la oportunidad para verificar el efecto del precursor de vanadio utilizado, llegándo a confirmar las ventajas del uso de oxalato de vanadilo.En lo que respecta a la deshidrogenación oxidativa de n-pentano, se encontró un comportamiento similar al observado con el butano pero con selectividades globales a olefinas menores.. Finalmente, para cuantificar los resultados y trasladarlos a un posible diseño de reactor, surgió la necesidad de desarrollar un programa que permitiera simularlos. Este aspecto se describe en el Capítulo 5 y está centrado en el catalizador MV4-30. El esfuerzo fue, desde nuestro punto de vista, satisfactorio, y dejó una estructura de cálculo disponible para ser utilizado con otros catalizadores y con reactores a escala banco. / Venezuelan surplus production of butanes and pentanes is a significant incentive for the development of new technologies that will help transforming them into products of added value. From a literature review presented in Chapter 1, a magnesium and vanadium oxide catalyst was found which showed the possibility for the development of a new way to produce non-saturated hydrocarbons through oxidative dehydrogenation. It was obvious that, in case this new technology was feasible, fluidized bed or mobile bed reactors would be needed to reduce the potential for explosive hydrocarbon-oxygen mix by separating hydrocarbon oxidation zones from those of the catalyst. Such a process has the additional advantage of producing a substantial selectivity increase. This catalyst however, does not offer the required attrition resistance characteristics. We propose to resolve this problem by adding an additional support like silica or alumina, materials commonly used in such reactors. Research efforts were dedicated to investigate the feasibility of such approach since these solids have superficial properties capable of modifying the type of compounds developed in the active phase. The main goal of this work was to bridge knowledge gaps in order to keep such approach alive. In order to assess potential extensions of such technology, some effort was dedicate to improve the active phase behavior by adding promoting components, and to analyze the behavior of the most promising catalysts for the oxidative dehydrogenation of n-pentane. We build a lab setup that would allow us to perform experiments and a set of catalysts were prepared. Catalysts were characterized in order to provide a foundation that would allow us to provide interpretation of observed behavior changes. For each one of these hydrocarbons, we also analyzed the effect of supporting and promoting components. The most extensively studied support material was silica. The main efforts were directed at quantifying the effect of the support on the activity, selectivity and on the optimal Mg/V ratio, as well as the effect of dilution. With increasing silica content we observed a decrease in activity while selectivity changes were mainly related to the products distribution but with global selectivity values similar to those of pure active phase with up to 30% of silica. No meaningful changes were observed with respect to the optimal Mg/V ratio. We determined that the MV4-30 catalyst had characteristics that would allow a new technology to be developed. Other promising supported catalysts that were found in our study were the Gamma30 and the Alfa30.Regarding to promoted catalysts, the following promoting agents were studied: Sb, Bi, Mo and Ga. Encouraging results were found in terms of selectivity. However, with the exception of gallium, these components had a negative impact on activity. Gallium did not affect activity values but improved the selectivity towards butadiene. We also had the opportunity to verify the effect of the vanadium precursor used in our studies and we were able to confirm significant advantages in the use of vanadil-oxalate.For the oxidative dehydrogenation of n-pentane we observed similar results but with lower global selectivity values. Obtained experimental results indicate the need to introduce changes in the catalyst which are outside the scope of this work.Finally, in order to quantify our results and to show that we would be able to translate them into effective values for reactor design, a software program was developed to simulate the experiments. Research efforts were, in our opinion, satisfactory and they resulted in a framework that could be used with other catalysts and in bank scale reactors.

Aquesta tesi es centra en el desenvolupament i l'ús d'una sonda miniaturitzada de silici per a la mesura de la impedància elèctrica de teixits vius tous. El propòsit d'aquestes mesures d'impedància és la monitorització en temps real del dany isquèmic per a aplicacions com la cirurgia cardíaca o el trasplantament d'òrgans. Actualment, el rang de mètodes aplicables a nivell clínic per tal de detectar l'isquèmia tissular és limitat i no existeix cap mètode pràctic que permeti la quantificació en temps real de l'efecte d'aquesta isquèmia, això és, el dany isquèmic. En aquest sentit, la monitorització de la impedància elèctrica sembla esperançadora i el treball d'aquesta tesi contribueix al camp mitjançant el desenvolupament de nous instruments i mètodes i mitjançant l'aportació de noves dades experimentals i eines per a la comprensió de la relació entre la patofisiologia i la impedància elèctrica. Les principals contribucions d'aquesta tesi es resumeixen a continuació.En aquesta tesi, es descriu el desenvolupament d'una sonda que formada per quatre elèctrodes de platí (300 &#61549;m &#61620; 300 &#61549;m) a sobre d'un substrat de silici en forma d'agulla ( longitud d'inserció = 9 mm i secció de 600 &#61549;m &#61620; 500 &#61549;m). Els elèctrodes estan situats a una distància de separació no constant per tal de millorar la relació senyal-soroll i la resolució espacial. Es realitza una deposició electroquímica de platí negre sobre els elèctrodes per tal de reduir la impedància de la interfície i millorar la qualitat de les mesures. En el cas dels teixits vius, la banda freqüencial de mesura va dels 100 Hz fins als 100 kHz. Un mètode nou per a la mesura d'impedància a cinc elèctrodes es presenta i s'analitza. Amb aquest mètode, es pretén minimitzar l'error a baixes freqüències degut a l'elevada impedància de la interfície elèctrode-electròlit. Malauradament, encara que aquest mètode a cinc elèctrodes funciona, s'han trobat algunes limitacions que el fan quasi impracticable en el cas dels teixits vius.També es presenta el desenvolupament i l'ús d'un paquet de programari per a simular la impedància elèctrica dels teixits vius en les regions de dispersió &#61537; i &#61538;. Aquest programari es basa en la generació d'arxius SPICE a partir de l'especificació d'alguns paràmetres numèrics relacionats amb el teixit i el dibuix d'un mapa bi-dimensional que representa un tall de teixit. El resultat més significatiu d'aquest simulador és que és capaç d'obtenir respostes compatibles amb l'equació de Cole a partir d'un model basat únicament en resistències i capacitats.S'han realitzat diversos estudis experimental fent servir la sonda de silici. En aquesta tesi únicament es presenten els estudis amb ronyons de rata. Els resultats confirmen les principals observacions fetes anteriorment per altres investigadors que han treballat amb diferents animals, òrgans i protocols. Això vol dir, en termes generals, un increment significatiu de la magnitud de la impedància elèctrica a baixes freqüències (< 10 kHz) durant el desenvolupament del procés isquèmic que s'associa a l'inflament cel·lular o al tancament de les unions inter-cel·lulars (gap junctions). Malgrat això, aquí també s'observa que un paràmetre derivat de la caracterització espectroscòpica de la impedància segons el model Cole, el paràmetre &#61537;, normalment ignorat per molts autors, és capaç de detectar alguns fets que no són detectats per la resta de paràmetres derivats de l'estudi de la impedància. Concretament es mostra que el valor de &#61537; podria estar relacionat amb la morfologia de l'espai extracel·lular i es demostra experimentalment que &#61537; pot ser modificat per una alteració induïda del citosquelet cel·lular.Addicionalment, aquesta tesi inclou un annex que tracta de facilitar la comprensió de la monitorització de la bioimpedància elèctrica a aquells amb formació en ciències de la vida. / This thesis is focused on the development and use of a miniaturized silicon probe for electrical impedance measurements of soft living tissues. The purpose of those impedance measurements is to monitor the ischemia injury for applications such as cardiac surgery or organ transplantation.Currently, the range of clinically available methods to detect tissue ischemia is limited and there is not any practical method to quantify in an on-line manner the effect of such ischemia, that is, the ischemia injury. In this sense, electrical impedance monitoring seems very promising and this thesis contributes to the field by developing new instruments and methods and by providing novel experimental results and tools to understand the relation between pathophysiology and electrical impedance. The main contributions of this thesis are summarized below.In this thesis, it is presented the development of a silicon probe that consists of four platinum electrodes (300 &#61549;m &#61620; 300 &#61549;m) on a needle shaped silicon substrate (9 mm insertion length, 600 &#61549;m &#61620; 500 &#61549;m cross section). The electrodes are placed at non-constant separation distance in order to enhance signal-to-noise ratio and spatial resolution. An electrochemical deposition of platinum black on the electrodes is performed in order to reduce the interface impedance and improve the quality of the measurements. For living tissue measurements, the useful measurement band goes from 100 Hz to 100 kHz.A novel measurement method based on five electrodes is described and analyzed. It is intended to minimize errors at low frequencies caused by the high electrode-electrolyte interface impedances. Unfortunately, although this five-electrode method works, some limitations have been found that made almost impossible its implementation for living tissue measurements.It is also presented a custom developed software package to simulate the electrical impedance of living tissues at the &#61537; and &#61538; dispersion regions. It is based on the generation of a SPICE netlist from the specification of some numerical parameters concerning the tissue and a bi-dimensional map representing a slice of tissue. Some examples are provided to demonstrate its feasibility. The most significant result is that the simulator is able to obtain Cole compatible behaviours from models based on simple resistances and capacitances. Several experimental studies have been performed by using the silicon probe. In this thesis only the experiments carried out on rat kidneys are presented. The results confirm the main observations made by previous researchers working with other animals, organs and protocols. That is, in general terms, a significant increase of impedance magnitude at low frequencies (<10 kHz) during the course of ischemia that is related to cell swelling or gap junctions closure. However, here it is also observed that a parameter from impedance spectroscopy characterization according to the Cole model, the &#61537; parameter, which is often ignored, is able to detect some events that are not revealed by other impedance parameters. It is shown that the &#61537; value could depend on the extracellular space morphology and it is experimentally demonstrated that &#61537; is modified by an induced alteration of cells cytoskeleton.This thesis includes an annex that tries to facilitate the understanding of electrical bioimpedance monitoring for life-sciences practitioners.Another annex describes the instrumentation systems that were developed for electrical impedance measurements based on the four-electrode method.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-04T23:12:17Z No. of bitstreams: 1 ELTHON ALEX DA SILVA OLIVEIRA - TESE PPGCC 2015..pdf: 4180608 bytes, checksum: 808dd922bbed2d1a31a83917caaf05c5 (MD5) / Made available in DSpace on 2018-05-04T23:12:17Z (GMT). No. of bitstreams: 1 ELTHON ALEX DA SILVA OLIVEIRA - TESE PPGCC 2015..pdf: 4180608 bytes, checksum: 808dd922bbed2d1a31a83917caaf05c5 (MD5) Previous issue date: 2015-05-08 / Diversas soluções de software têm sido desenvolvidas para a área de cuidados de saúde. Nesta área, destacam-se as pesquisas em exercícios físicos, que tem recebido grande atenção da Organização Mundial de Saúde por ajudar a diminuir os riscos de diversas doenças e a aumentar a qualidade de vida das pessoas acometidas por alguma delas. Contudo, há três problemas principais nas soluções existentes desenvolvidas para o acompanhamento de exercícios físicos: i) levam em consideração apenas variáveis fisiológicas, ii) necessitam da atenção do profissional de saúde durante a prática do exercício e iii) não fornecem recomendações customizadas. Neste trabalho, é apresentado um método para proporcionar a manutenção de conformidade entre as ações dos indivíduos e as recomendações do profissional de saúde, durante a prática de exercícios, sem a presença do mesmo in loco. Tal método possibilita a construção de um modelo na forma de autômato finito. Este autômato, chamado de modelo de referência, é capaz de descrever como o indivíduo deve se comportar a fim de se manter em conformidade com as recomendações do profissional de saúde. Por ser gerado a partir da composição de modelos menores, a evolução do modelo pode ser obtida e as propriedades garantidas por construção. Além disso, propriedades de vivacidade e segurança são verificadas no modelo construído por meio da técnica de verificação de modelos, fornecendo confiabilidade ao sistema. Algumas tarefas foram executadas no processo de avaliação do método apresentado e demonstraram que: o processo de construção do modelo de referência está de acordo com o processo clínico; o modelo gerado é capaz de representar o conhecimento do especialista, fornecendo recomendações adequadas ao indivíduo; e a solução apresentada é tecnicamente viável de se implementada e executada; e,por fim,este método pode ser usado em cenários reais,desde que os indivíduos não estejam sob condições de estresse. / Several software solutions have been developed for the healthcare area. In this area, we high light the area of physical exercise that has received great attention from World Health Organization for helping decreasing risk of various diseases and improving the quality of life of people affected by some of them. However, there are three main problems with such solutions developed for monitoring of physical exercises: i) only physiological variables are supported, ii) professional attention is required during the exercise, and iii) customized recommendations are not given. In this work,we present a method to provide accordance maintenance between individuals actions and recommendations from health care professional, during the exercise execution, without the presence of himin loco. Such a method makes it possible to build a finite automaton model. Such an automaton, called reference model, describes how an individual must behave aiming to follow recommendations from the health care professional. As it is obtained by means of composition from smaller models, the model evolution is accomplished and properties are guaranteed by means of building process. Besides, liveness and safety properties are checked in the model by the model checking technique,making the model more reliable. Some tasks were performed during the evaluation process and showed that: the building process of the reference model is according to the clinical procedure; the generated reference model is able to represent the knowledge of the health care professional by providing appropriate recommendations; the presented solution is technically feasible to be developed and executed; and such a method can be used in real scenarios, since individuals are not under stress conditions.