52 resultados para Variáveis climáticas


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This research investigates the microclimate and the morphology features of the central campus of the UFRN, in Natal-RN, through the use of bioclimatic tools of analysis in order to assist the implementation of the campus´ Master Plan. It develops a diagnosis of the evolution and growth of the urban space surveyed by analyzing its initial plan and the basic urban conception behind it, as well as the morphology and typologies utilized. The study makes a qualitative analysis of the local microclimate by using Katzschner (1997) methodology, with land-use and topography maps, building heights, vegetation and soil covering. It also makes use of the methodology proposed by Oliveira (1993), which examines, from the bioclimatic standpoint, the human environment as related to the urban form (site and built mass). It identifies zones whose climatic characteristics are representative of the local microclimate and classifies them into areas to be strictly preserved, areas to be protected and areas to be improved. By means of the methodology for spatial and environmental assessment developed by Bustos Romero (2001), the survey selects characteristic points of each area in order to register the environmental data relative to the two basic seasons found in the region where the campus is located, that is, the dry and the rainy season, so that it can evaluate changes in the environment which might have been caused by urban density growth, by arborization or by the influence of the urban form. It then proceeds to a quantitative and statistical survey of the collected data with the purpose of evaluating the degree of influence of the identified features over the environmental variables along the different scales of approach. The study shows the existence of different microclimates and emphasizes the relevance of the bioclimatic analysis of the built environment as a tool for the decision-making process along the development of the Master Plan for UFRN Central Campus

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This master thesis aims to assess the influence of the design decisions on the energy building performance of hotels. The research is based on the integration of field study and computer simulation. Firstly, a detailed field study is carried out to identify the characteristics of hotels in Natal, Rio Grande do Norte. The items assessed are occupancies, light and equipment densities, types of air conditioning, total and monthly energy consumption, among others. A second and more comprehensive field study is carried out to identify the range of occurrence of architectural variables, with a larger number of buildings. A base case is modelled in VisualDOE, based on the first field study. Then, a first set of simulations are run to explore the sensitivity of the variables on the energy consumption. The results analyses were the base of a second set of simulations, which combined the most influential variables. The results of 384 models were assessed, and the impacts of design decisions were quantified. The study discusses tendencies and recommendations, as well as the methods advantages and disadvantages

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The metalceramic crowns are usually used in dentistry because they provide a resistant structure due to its metallic base and its aesthetics from the porcelain that recovers this structure. To manufacture these crowns, a series of stages should be accomplished in the prosthetic laboratories, and many variables can influence its success. Changes in these variables cause alterations in the metallic alloy and in the porcelain, so, as consequence, in the adhesion between them. The composition of the metal alloy can be modified by recasting alloys, a common practice in some prosthetic laboratories. The aim of this paper is to make a systematic study investigating metalceramic crowns as well as analyzing the effect of recasting Ni-Cr alloys. Another variable which can influence the mechanism of metalceramic union is the temperature used in firing porcelain procedure. Each porcelain has to be fired in a fixed temperature which is determined by the manufacturer and its change can cause serious damages. This research simulate situations that may occur on laboratory procedures and observe their consequences in the quality of the metalceramic union. A scanning eletron microscopy and an optic microscopy were accomplish to analyse the metal-ceramic interface. No differences have been found when remelting alloys were used. The microhardness were similar in Ni-Cr alloys casted once, twice and three times. A wettability test was accomplished using a software developed at the Laboratório de Processamento de Materiais por Plasma, on the Universidade Federal do Rio Grande do Norte. No differences were found in the contact angle between the solid surface (metallic substratum) and the tangencial plane to the liquid surface (opaque). To analyse if the temperature of porcelain firing procedure could influence the contact area between metal and porcelain, a variation in its final temperature was achieve from 980° to 955°C. Once more, no differences have been found

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This work aims to obtain a low-cost virtual sensor to estimate the quality of LPG. For the acquisition of data from a distillation tower, software HYSYS ® was used to simulate chemical processes. These data will be used for training and validation of an Artificial Neural Network (ANN). This network will aim to estimate from available simulated variables such as temperature, pressure and discharge flow of a distillation tower, the mole fraction of pentane present in LPG. Thus, allowing a better control of product quality

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The composition of termite assemblages was analyzed at three Caatinga sites of the Seridó Ecological Station, located in the municipality of Serra Negra do Norte, in the state of Rio Grande do Norte, Brazil. These sites have been subjected to selective logging, and cleared for pasture and farming. A standardized sampling protocol for termite assemblages (30h/person/site) was conducted between September 2007 and February 2009. At each site we measured environmental variables, such as soil granulometry, pH and organic matter, necromass stock, vegetation height, tree density, stem diameter at ankle height (DAH) and the largest and the smallest crown width. Ten species of termites, belonging to eight genera and three families, were found at the three experimental sites. Four feeding-groups were sampled: wood-feeders, soil-feeders, wood-soil interface feeders and leaf-feeders. The wood-feeders were dominant in number of species and number of encounters at all sites. In general, the sites were not significantly different in relation to the environmental variables measured. The same pattern was observed for termite assemblages, where no significant differences in species richness, relative abundance and taxonomic and functional composition were observed between the three sites. The agreement between the composition of assemblages and environmental variables reinforces the potential of termites as biological indicators of habitat quality

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The Northeast of Brazil (NEB) shows high climate variability, ranging from semiarid regions to a rainy regions. According to the latest report of the Intergovernmental Panel on Climate Change, the NEB is highly susceptible to climate change, and also heavy rainfall events (HRE). However, few climatology studies about these episodes were performed, thus the objective main research is to compute the climatology and trend of the episodes number and the daily rainfall rate associated with HRE in the NEB and its climatologically homogeneous sub regions; relate them to the weak rainfall events and normal rainfall events. The daily rainfall data of the hydrometeorological network managed by the Agência Nacional de Águas, from 1972 to 2002. For selection of rainfall events used the technique of quantiles and the trend was identified using the Mann-Kendall test. The sub regions were obtained by cluster analysis, using as similarity measure the Euclidean distance and Ward agglomerative hierarchical method. The results show that the seasonality of the NEB is being intensified, i.e., the dry season is becoming drier and wet season getting wet. The El Niño and La Niña influence more on the amount of events regarding the intensity, but the sub-regions this influence is less noticeable. Using daily data reanalysis ERAInterim fields of anomalies of the composites of meteorological variables were calculated for the coast of the NEB, to characterize the synoptic environment. The Upper-level cyclonic vortex and the South atlantic convergene zone were identified as the main weather systems responsible for training of EPI on the coastland

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The increase in ultraviolet radiation (UV) at surface, the high incidence of non-melanoma skin cancer (NMSC) in coast of Northeast of Brazil (NEB) and reduction of total ozone were the motivation for the present study. The overall objective was to identify and understand the variability of UV or Index Ultraviolet Radiation (UV Index) in the capitals of the east coast of the NEB and adjust stochastic models to time series of UV index aiming make predictions (interpolations) and forecasts / projections (extrapolations) followed by trend analysis. The methodology consisted of applying multivariate analysis (principal component analysis and cluster analysis), Predictive Mean Matching method for filling gaps in the data, autoregressive distributed lag (ADL) and Mann-Kendal. The modeling via the ADL consisted of parameter estimation, diagnostics, residuals analysis and evaluation of the quality of the predictions and forecasts via mean squared error and Pearson correlation coefficient. The research results indicated that the annual variability of UV in the capital of Rio Grande do Norte (Natal) has a feature in the months of September and October that consisting of a stabilization / reduction of UV index because of the greater annual concentration total ozone. The increased amount of aerosol during this period contributes in lesser intensity for this event. The increased amount of aerosol during this period contributes in lesser intensity for this event. The application of cluster analysis on the east coast of the NEB showed that this event also occurs in the capitals of Paraiba (João Pessoa) and Pernambuco (Recife). Extreme events of UV in NEB were analyzed from the city of Natal and were associated with absence of cloud cover and levels below the annual average of total ozone and did not occurring in the entire region because of the uneven spatial distribution of these variables. The ADL (4, 1) model, adjusted with data of the UV index and total ozone to period 2001-2012 made a the projection / extrapolation for the next 30 years (2013-2043) indicating in end of that period an increase to the UV index of one unit (approximately), case total ozone maintain the downward trend observed in study period

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The soil macrofauna is influenced to several biotic and abiotic environmental factors, from changes in the physical environment to a variety of interactions among the species involved, affecting the patterns of biodiversity of soil fauna. The power and specificity of the mechanisms that act on soil organisms vary greatly depending on environmental conditions at different scales of space and time. The Caatinga has great spatial heterogeneity of vegetation, climate and soil, so the soil macrofauna would follow this local spatial variation in the environment? This study aimed to investigate the effects of local environmental variables on biological parameters (taxa richness, total abundance and biomass) of soil macrofauna in a fragment of caatinga in João Câmara, Rio Grande Norte, Northeast Brazil. The study was conducted in the Cauaçu farm, where a grid of 2000m x 500m was drawn, and later, 30 sampling points were randomly selected. The methodology used to collect the macrofauna was the TSBF method. We tested the effects of 10 environmental variables on macrofauna across the plots and across the layers of soil. The hypothesis that macrofauna soil responds to changes in the environment was not supported throughout the plots, but was confirmed to soil layers. The soil macrofauna shows a pattern of concentration in the surface layer and decreases considerably in the deeper layers. This pattern had significant and positive relationship with the aerial plant biomass and fine root stock. The aerial plant biomass releases plant necromass that accumulates in the surface layer, providing an important source of resource and shelter for soil macrofauna, explaining their greater abundance in this layer. The roots are used as a means for the arrival of nutrients to the soil from the primary production, thus a greater amount of root conditions higher food intake for macrofauna, especially the herbivores

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The Brazilian Northeast is the most vulnerable region to climatic variability risks. For the Brazilian semi-arid is expected a reduction in the overall rates of precipitation and an increase in the number of dry days. These changes predicted by the IPCC (2007) will intensify the rainfall and droughts period that could promote the dominance of cyanobacteria, thus affecting the water quality of reservoirs, that are most used for water supply, in the semi-arid. The aim of this study was to evaluate the effects of increasing temperature combined with nutrient enrichment on the functional structure of the phytoplankton community of a mesotrophic reservoir in the semi-arid, in the worst case scenario of climate change predicted by the IPCC (2007). Two experiments were performed, one in a rainy season and another in the dry season. In the water sampled, nutrients (nitrate and orthophosphate) were added in different concentrations. The microcosms were submitted to two different temperatures, five-year average of air temperature in the reservoir (control) and 4°C above the control temperature (warming). The results of this study showed that warming and nutrient enrichment benefited mainly the functional groups of cyanobacteria. During the rainy season it was verified the increasing biomass of small functional groups of unicellular and opportunists algae such as F (colonial green algae with mucilage) and X1 (nanoplanktonic algae of eutrophic lake systems). It was also observed an increasing in total biomass, in the richness and diversity of the community. In the dry season experiment there was a greater contribution in the relative biomass of filamentous algae, with a replacement of the group S1 (non-filamentous cyanobacteria with heterocytes) for H1 (filamentous cyanobacteria with heterocytes) in nutrient- enriched treatments. Moreover, there was also loss in total biomass, species richness and diversity of the community. The effects of temperature and nutrients manipulation on phytoplankton community of reservoir Ministro João Alves provoked changes in species richness, the diversity of the community and its functional composition, being the dry period which showed the highest susceptibility to the increase in the contribution of potentially toxic cyanobacteria with heterocytes

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The methods of analysis of the selection system sports talent sometimes do not consider the biological age of the athletes, since that the assessment of maturational moment have several limitations The aim of this work is to develop a predictive equation of pubertal assessment in male subjects, based on anthropometric measurements. We evaluated 206 young boys, aged between eight and 18 years, and studing in public and private schools in Natal, Brazil. The sample selection was done randomly, being used the anthropometric measurements and pubertal maturation evaluation according to the Tanner stages. Statistical analysis followed the presentation of central tendency measures and their derivatives. The inferential analysis was performed according to the ANOVA test, multivariate discriminant analysis and weighted Kappa. The advancement of pubertal stages was accompanied by significant changes in anthropometric variables, demonstrating the relationship presented in both. For this purpose, discriminant analysis selected eight variables with the highest prediction of pubertal maturation, and created an equation with a significance level of 75%. and concordance level of 0.840, considered as excellent. This shows that the prediction of pubertal maturation from anthropometric variables presented as a valid method, being used as a practical tool in sports talents selection

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Demand for organic foods within in Brazil are growing, characterizing itself for if constituting in a new strategical segment of commercialization. In this context, the objective of this research was to investigate the variables used by consumers in the purchase decision of organic products, aiming to characterize the level of competitiveness of these products, assisting in the creation of environmental strategies for the development of the activity and contributing in the increment of the knowledge about the subject, that can assist it in the increase of the commercialization and the consumption of these foods. From data collected in the city of Natal/RN, it was used a survey research, of exploratory and descriptive character. The sample was obtained using 401 questionnaires, in which was realized: the Test of Comparison of Averages, Descriptive analysis, analysis of Cluster and Qui-square. The results found in this study indicate that the main reasons for the organic food purchase are the absence of chemical pesticides in the product, followed by the care with own health and of the household. The main characteristics in the consumers of supermarkets, that are associates with purchase frequency of organic foods are the environmental behavior and lifestyle. Among the profile characteristics, gender, age and number of children are associates with the purchase frequency of these foods and the income and level education not showed association

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The limits to inform is about the character stico of basic, quimica, mineralogical and mechaniques of matlaughed material used in the manufacturing process the product certified in economic region the Cariri, specifically in the city of Crato, Ceará state, motivated the development of this work, since in this region the exist ing economic context that a general appear as important in the production chains. Were made twentyfive soils-test specimen collection and the study was performed to differentiate the mat laugh materials of variaveis processing of mathing raw materials in the factory The product mica monkeys by extrusion and pressing. The results were obtained ap s as analyzes: grain size, index of plasticity, fluoresce incidence X-ray difration the X-ray, and analyzes thermicals and properties technological. through s of curves gresifica returned to was a comparison between the retro the linear, absorb to water, porosity and bulk density. the results show that the excellent distribution and character acceptable available for the processing of the structure color dark red. needing, therefore, of the mixture of a less plastic clay with thick granulation, that works as plasticity reducer. In spite of the different resignation forms for prensagem and extrusion, the characteristics of absorption of water and rupture tension the flexing was shown inside of the patterns of ABNT

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Among the main challenges in the beer industrial production is the market supply at the lowest cost and high quality, in order to ensure the expectations of customers and. consumers The beer fermentation stage represents approximately 70% of the whole time necessary to its production, having a obligatoriness of strict process controls to avoid becoming bottleneck in beer production. This stage is responsible for the formation of a series of subproducts, which are responsible for the composition of aroma/bouquet existing in beer and some of these subproducts, if produced in larger quantities, they will confer unpleasant taste and odor to the final product. Among the subproducts formed during the fermentation stage, total vicinal diketones is the main component, since it is limiting for product transfusion to the subsequent steps, besides having a low perception threshold by the consumer and giving undesirable taste and odor. Due to the instability of main raw materials quality and also process controls during fermentation, the development of alternative forms of beer production without impacting on total fermentation time and final product quality is a great challenge to breweries. In this work, a prior acidification of the pasty yeast was carried out, utilizing for that phosphoric acid, food grade, reducing yeast pH of about 5.30 to 2.20 and altering its characteristic from flocculent to pulverulent during beer fermentation. An increase of six times was observed in amount of yeast cells in suspension in the second fermentation stage regarding to fermentations by yeast with no prior acidification. With alteration on two input variables, temperature curve and cell multiplication, which goal was to minimize the maximum values for diketones detected in the fermenter tank, a reduction was obtained from peak of formed diacetyl and consequently contributed to reduction in fermentation time and total process time. Several experiments were performed with those process changes in order to verify the influence on the total fermentation time and total vicinal diketones concentration at the end of fermentation. This experiment reached as the best production result a total fermentation time of 151 hours and total vicinal diketone concentration of 0.08 ppm. The mass of yeast in suspension in the second phase of fermentation increased from 2.45 x 106 to 16.38 x 106 cells/mL of yeast, which fact is key to a greater efficiency in reducing total vicinal diketones existing in the medium, confirming that the prior yeast acidification, as well as the control of temperature and yeast cell multiplication in fermentative process enhances the performance of diketones reduction and consequently reduce the total fermentation time with diketones concentration below the expected value (Max: 0.10 ppm)

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The aim of this approach is to describe the design and construction of a low-cost automated water sampler prototype. In recent years, there is an increasing need on the use of automated equipments for hydro climatic variables to be use in urban and rural environments. Such devices are always used to provide measured information which is of crucial importance on the development of water resources strategies at watershed scale. Actually, many research and water public institutions have been using these kinds of equipments. In most of the cases, automated equipments are expensive and need to be imported, generating a situation of technologic dependency. The prototype is based on an electronic system which controls a peristaltic pump functioning, five solenoid valves and an ultrasonic sensor connected to a datalloger. An interface with the user allows communication with a PC, when the equipment functioning parameters can be provided. The equipment has a hydraulic module composed by a 12V peristaltic pump connected to a distribution circuit composed by five solenoid valves, one of them being used to clean the circuit before each sampling procedure. Samples are collected by four 1.95 polyethylene bottles. The sampler body was made of acrylic material, with a cylindrical shape, and dimensions 0.72 m and 0.38 m height and diameter, respectively. The weight of the equipment without samples is approximately 15 kg, which infers to its portability. The prototype development total cost budget was approximately US$ 1,560.00. Laboratory tests aimed to evaluate the equipment performance and functioning demonstrated satisfactory results

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The interaction between land and water, resulting from dynamic agents, such as wind, waves and tides, characterizes the coastal zone as a dynamic environment that is constantly disturbed and that may alter the balance of natural and man-made environment. Such modifications may be intensified when considering the climate change. This environment is highly attractive for the development of economic activities and urbanization, current scenario of the city of Natal. Weighing the economic importance for the state and the physical environment in which the capital of Rio Grande do Norte is inserted, this study aims to identify and analyze vulnerabilities and impacts caused by the rising sea level in the municipality. To that end, we defined a coastline, delimited areas susceptible to flooding and presented some flood scenarios. This way we could identify and analyze the impacts of each flood scenario in its respective section. Finally, it appears that the coastal zone in which Natal is inserted is a fragile area that requires actions aimed at mitigating vulnerabilities and facing the problem that caused the rise in the mean sea level (MSL), and mitigating the presented vulnerability framework; it is necessary to implement actions that effectively contribute to the protection and adaptation of the most fragile areas