5 resultados para PYRAMIDAL INDENTATION
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
The accomplished researches in the education field focus on the importance of the accomplishment of actions involved in the analysis of the needs to graduate teachers as a way to adequate to socialcultural changing that require more and more a creative activity to prepare teachers in their graduation perspective. The worry with a fail at school linked to public school students lead us to make this thesis which goals are: investigate the needs of the graduation of teachers at public Elementary Schools concerning to the subjacent knowledge to the development of a pedagogic practice of alphabetizing with literacy and (re)create, with some teachers as active participants in the researches, knowledge regarding the process of alphabetization with literacy , based on the graduation of teachers. The study was accomplished in a municipal Elementary School in the Ceará-Mirim city, located in the state of Rio Grande do Norte, which offers both I and II levels of the Elementary School, 7 teachers and the principal of the school were subjects of our researches. The starting point was the needs of the graduation as subject phenomena, socially created and that allow people to be aware of the goals of a graduation. The investigative broach is qualitative, whose fundamental purpose is the understanding of the meanings, symbols, values and intentions of the mankind actions, as regards to other humanbeing and the contexts in which they interact. Within this context, we chose the investigation-action for we consider this kind of research a place for investigation and professional graduation, in which teachers and the researcher herself assume responsibility of problematizing, build the needs of graduation and think about their practices. As proceedings to create and analyze data, we developed participant observations during the activities in classroom; semi-structured interviews (individual and in groups) with teachers and the principal; analysis of documents and meetings at school for reflexive studies that enabled us to gather data in a pyramidal panoramic view and analyze the contents. The research revealed that the analysis of necessities to graduate teachers is a resource able to contribute to the planning of projects of keeping on graduating more properly, and thus create a critical and reflexive identity for teachers. This way, it was possible the graduation necessities could be revealed and also the knowledge of teachers as regards to alphabetization inserted in a perspective of literacy. Nowadays, conceptualized needs upon difficulties of teachers, there is a tendency to translate them into theorization of problems, without application to these knowledge of teachers, as well as their wishes for changing, especially when those needs are built to analyze and consider concrete practices. Therefore, the graduation experiences have enabled the abandon of a mechanical broach for teaching reading and writing. It has also lead teachers to assume a posture of providing their students the understanding about the reading and writing processes and their functions as social instruments. The graduation theme contents allowed the knowledge to conceive reading and writing in new perspectives, according to their social functions, so that they can improve the education with literacy quality. This theoretical construction has enabled us to understand and consider the necessities of the graduation as progressive process, and has given us the possibility of re-think our own learning processes at the university and review the pedagogical practices of public school teachers. Our conclusion is that once teachers consider their own graduation needs, it contributes to change their concepts and practices in education and literacy, even though there used to be many difficulties in their graduation and organization of the pedagogical work
Resumo:
Experiments were performed to study the effect of surface properties of a vertical channel heated by a source of thermal radiation to induce air flow through convection. Two channels (solar chimney prototype) were built with glass plates, forming a structure of truncated pyramidal geometry. We considered two surface finishes: transparent and opaque. Each stack was mounted on a base of thermal energy absorber with a central opening for passage of air, and subjected to heating by a radiant source comprises a bank of incandescent bulbs and were performed field tests. Thermocouples were fixed on the bases and on the walls of chimneys and then connected to a data acquisition system in computer. The air flow within the chimney, the speed and temperature were measured using a hot wire anemometer. Five experiments were performed for each stack in which convective flows were recorded with values ranging from 17 m³ / h and 22 m³ / h and air flow velocities ranging from 0.38 m / s and 0.56 m / s for the laboratory tests and air velocities between 0.6 m/s and 1.1m/s and convective airflows between 650 m³/h and 1150 m³/h for the field tests. The test data were compared to those obtained by semi-empirical equations, which are valid for air flow induced into channels and simulated data from 1st Thermodynamics equation. It was found that the chimney with transparent walls induced more intense convective flows than the chimney with matte finish. Based on the results obtained can be proposed for the implementation of prototype to exhaust fumes, mists, gases, vapors, mists and dusts in industrial environments, to help promote ventilation and air renewal in built environments and for drying materials, fruits and seeds
Resumo:
Cortical interneurons are characterized by their distinct morphological, physiological and biochemical properties, acting as modulators of the excitatory activity by pyramidal neurons, for example. Various studies have revealed differences in both distribution and density of this cell group throughout distinct cortical areas in several species. A particular class of interneuron closely related to cortical modulation is revealed by the immunohistochemistry for calcium binding proteins calbindin (CB), calretinina (CR) and parvalbumin (PV). Despite the growing amount of studies focusing on calcium binding proteins, the prefrontal cortex of primates remains relatively little explored, particularly in what concerns a better understanding of the organization of the inhibitory circuitry across its subdivisions. In the present study we characterized the morphology and distribution of neurons rich in calcium-binding proteins in the medial, orbital and dorsolateral areas of the prefrontal cortex of the marmoset (Callithrix jacchus). Using both morphometric and stereological techniques, we found that CR-reactive neurons (mainly double bouquet and bipolar cells) have a more complex dendritic arborization than CB-reactive (bitufted and basket cells) and PV-reactive neurons (chandelier cells). The neuronal densities of CR- and CB-reactive cells are higher in the supragranular layers (II/III) whilst PV-reactive neurons, conversely, are more concentrated in the infragranular layers (V/VI). CR-reactive neurons were the predominant group in the three regions evaluated, being most prevalent in dorsomedial region. Our findings point out to fundamental differences in the inhibitory circuitry of the different areas of the prefrontal cortex in marmoset
Resumo:
In recent decades, changes in the surface properties of materials have been used to improve their tribological characteristics. However, this improvement depends on the process, treatment time and, primarily, the thickness of this surface film layer. Physical vapor deposition (PVD) of titanium nitrate (TiN) has been used to increase the surface hardness of metallic materials. Thus, the aim of the present study was to propose a numerical-experimental method to assess the film thickness (l) of TiN deposited by PVD. To reach this objective, experimental results of hardness (H) assays were combined with a numerical simulation to study the behavior of this property as a function of maximum penetration depth of the indenter (hmax) into the film/substrate conjugate. Two methodologies were adopted to determine film thickness. The first consists of the numerical results of the H x hmax curve with the experimental curve obtained by the instrumental indentation test. This methodology was used successfully in a TiN-coated titanium (Ti) conjugate. A second strategy combined the numerical results of the Hv x hmax curve with Vickers experimental hardness data (Hv). This methodology was applied to a TiN-coated M2 tool steel conjugate. The mechanical properties of the materials studied were also determined in the present study. The thicknesses results obtained for the two conjugates were compatible with their experimental data.
Resumo:
Registration of point clouds captured by depth sensors is an important task in 3D reconstruction applications based on computer vision. In many applications with strict performance requirements, the registration should be executed not only with precision, but also in the same frequency as data is acquired by the sensor. This thesis proposes theuse of the pyramidal sparse optical flow algorithm to incrementally register point clouds captured by RGB-D sensors (e.g. Microsoft Kinect) in real time. The accumulated errorinherent to the process is posteriorly minimized by utilizing a marker and pose graph optimization. Experimental results gathered by processing several RGB-D datasets validatethe system proposed by this thesis in visual odometry and simultaneous localization and mapping (SLAM) applications.