999 resultados para Building morphology
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Vegetation and building morphology characteristics are investigated at 19 sites on a north-south LiDAR transect across the megacity of London. Local maxima of mean building height and building plan area density at the city centre are evident. Surprisingly, the mean vegetation height (zv3) is also found to be highest in the city centre. From the LiDAR data various morphological parameters are derived as well as shadow patterns. Continuous images of the effects of buildings and of buildings plus vegetationon sky view factor (Ψ) are derived. A general reduction of Ψ is found, indicating the importance of including vegetation when deriving Ψ in urban areas. The contribution of vegetation to the shadowing at ground level is higher during summer than in autumn. Using these 3D data the influence on urban climate and mean radiant temperature (T mrt ) is calculated with SOLWEIG. The results from these simulations highlight that vegetation can be most effective at reducing heat stress within dense urban environments in summer. The daytime average T mrt is found to be lowest in the densest urban environments due to shadowing; foremost from buildings but also from trees. It is clearly shown that this method could be used to quantify the influence of vegetation on T mrt within the urban environment. The results presented in this paper highlight a number of possible climate sensitive planning practices for urban areas at the local scale (i.e. 102- 5 × 103 m).
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The solar and longwave environmental irradiance geometry (SOLWEIG) model simulates spatial variations of 3-D radiation fluxes and mean radiant temperature (T mrt) as well as shadow patterns in complex urban settings. In this paper, a new vegetation scheme is included in SOLWEIG and evaluated. The new shadow casting algorithm for complex vegetation structures makes it possible to obtain continuous images of shadow patterns and sky view factors taking both buildings and vegetation into account. For the calculation of 3-D radiation fluxes and T mrt, SOLWEIG only requires a limited number of inputs, such as global shortwave radiation, air temperature, relative humidity, geographical information (latitude, longitude and elevation) and urban geometry represented by high-resolution ground and building digital elevation models (DEM). Trees and bushes are represented by separate DEMs. The model is evaluated using 5 days of integral radiation measurements at two sites within a square surrounded by low-rise buildings and vegetation in Göteborg, Sweden (57°N). There is good agreement between modelled and observed values of T mrt, with an overall correspondence of R 2 = 0.91 (p < 0.01, RMSE = 3.1 K). A small overestimation of T mrt is found at locations shadowed by vegetation. Given this good performance a number of suggestions for future development are identified for applications which include for human comfort, building design, planning and evaluation of instrument exposure.
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To bridge the gaps between traditional mesoscale modelling and microscale modelling, the National Center for Atmospheric Research, in collaboration with other agencies and research groups, has developed an integrated urban modelling system coupled to the weather research and forecasting (WRF) model as a community tool to address urban environmental issues. The core of this WRF/urban modelling system consists of the following: (1) three methods with different degrees of freedom to parameterize urban surface processes, ranging from a simple bulk parameterization to a sophisticated multi-layer urban canopy model with an indoor–outdoor exchange sub-model that directly interacts with the atmospheric boundary layer, (2) coupling to fine-scale computational fluid dynamic Reynolds-averaged Navier–Stokes and Large-Eddy simulation models for transport and dispersion (T&D) applications, (3) procedures to incorporate high-resolution urban land use, building morphology, and anthropogenic heating data using the National Urban Database and Access Portal Tool (NUDAPT), and (4) an urbanized high-resolution land data assimilation system. This paper provides an overview of this modelling system; addresses the daunting challenges of initializing the coupled WRF/urban model and of specifying the potentially vast number of parameters required to execute the WRF/urban model; explores the model sensitivity to these urban parameters; and evaluates the ability of WRF/urban to capture urban heat islands, complex boundary-layer structures aloft, and urban plume T&D for several major metropolitan regions. Recent applications of this modelling system illustrate its promising utility, as a regional climate-modelling tool, to investigate impacts of future urbanization on regional meteorological conditions and on air quality under future climate change scenarios. Copyright © 2010 Royal Meteorological Society
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This study focuses on the building ensemble of Avenida Roberto Freire, a main road in Natal, Brazil, as a material expression of the confluence of various factors among which the following may be emphasized: high level of accessibility due to urban spatial re-structuring and the growth of the real estate market, in view of the increasing number of consumers, who arrived in Natal within the last decades. The intense urban modification process that has been going on in Natal since at least the 1980s, has engendered the formation of long axial lines which express the expansion dynamics and some of the forces subjacent to it. Avenida Roberto Freire has been an iconic example of an urban thoroughfare where architecture becomes primarily a communication support that can be perceived by fast moving passers-by, what brings it close to the venturian concept of strip (Venturi at al, 1972). The building types that line the road not only respond to the dynamics in process but also contribute to intensify it, as they house a variety of uses which attract people and generate more movement. The dynamics is further strengthened by the action of the real estate business which benefits from the increase of highly accessible locations, and from the private and public investments and incentives to tourism that aim to insert this city into the globalized world. Although the intention of reconstituting part of the history of density increase on this avenue in a diachronical perspective was attempted within the limits of the available references and documentation, the central contribution of this study is to understand the relations between topological accessibility and the typological nature of the building ensemble. By observing the synchronic morphological frame resulting from the spatial configuration analysis pertinent to this avenue (cf. Hillier and Hanson,1984) and the inventory and classification of the building ensemble there existing, this study aims to understand how architecture responds to accessibility in view of the real estate pressure, boosted by a cosmopolitanizing process brought about by the continuous flow of foreign and Brazilian arrivals as visitors, temporary or permanent residents
Resumo:
This study focuses on the building ensemble of Avenida Roberto Freire, a main road in Natal, Brazil, as a material expression of the confluence of various factors among which the following may be emphasized: high level of accessibility due to urban spatial re-structuring and the growth of the real estate market, in view of the increasing number of consumers, who arrived in Natal within the last decades. The intense urban modification process that has been going on in Natal since at least the 1980s, has engendered the formation of long axial lines which express the expansion dynamics and some of the forces subjacent to it. Avenida Roberto Freire has been an iconic example of an urban thoroughfare where architecture becomes primarily a communication support that can be perceived by fast moving passers-by, what brings it close to the venturian concept of strip (Venturi at al, 1972). The building types that line the road not only respond to the dynamics in process but also contribute to intensify it, as they house a variety of uses which attract people and generate more movement. The dynamics is further strengthened by the action of the real estate business which benefits from the increase of highly accessible locations, and from the private and public investments and incentives to tourism that aim to insert this city into the globalized world. Although the intention of reconstituting part of the history of density increase on this avenue in a diachronical perspective was attempted within the limits of the available references and documentation, the central contribution of this study is to understand the relations between topological accessibility and the typological nature of the building ensemble. By observing the synchronic morphological frame resulting from the spatial configuration analysis pertinent to this avenue (cf. Hillier and Hanson,1984) and the inventory and classification of the building ensemble there existing, this study aims to understand how architecture responds to accessibility in view of the real estate pressure, boosted by a cosmopolitanizing process brought about by the continuous flow of foreign and Brazilian arrivals as visitors, temporary or permanent residents
Resumo:
This study focuses on the building ensemble of Avenida Roberto Freire, a main road in Natal, Brazil, as a material expression of the confluence of various factors among which the following may be emphasized: high level of accessibility due to urban spatial re-structuring and the growth of the real estate market, in view of the increasing number of consumers, who arrived in Natal within the last decades. The intense urban modification process that has been going on in Natal since at least the 1980s, has engendered the formation of long axial lines which express the expansion dynamics and some of the forces subjacent to it. Avenida Roberto Freire has been an iconic example of an urban thoroughfare where architecture becomes primarily a communication support that can be perceived by fast moving passers-by, what brings it close to the venturian concept of strip (Venturi at al, 1972). The building types that line the road not only respond to the dynamics in process but also contribute to intensify it, as they house a variety of uses which attract people and generate more movement. The dynamics is further strengthened by the action of the real estate business which benefits from the increase of highly accessible locations, and from the private and public investments and incentives to tourism that aim to insert this city into the globalized world. Although the intention of reconstituting part of the history of density increase on this avenue in a diachronical perspective was attempted within the limits of the available references and documentation, the central contribution of this study is to understand the relations between topological accessibility and the typological nature of the building ensemble. By observing the synchronic morphological frame resulting from the spatial configuration analysis pertinent to this avenue (cf. Hillier and Hanson,1984) and the inventory and classification of the building ensemble there existing, this study aims to understand how architecture responds to accessibility in view of the real estate pressure, boosted by a cosmopolitanizing process brought about by the continuous flow of foreign and Brazilian arrivals as visitors, temporary or permanent residents
Resumo:
The objective of the present research was to evaluate the effect of fibre morphology (e.g., length, width, fibrillation, broken ends, content of fines and number of fibres per gram) on flocculation and drainage properties of fibre-cement suspensions and on physical properties of the fibre-cement composites. Mechanical refining was used to change the morphological properties of Eucalyptus and Pinus pulps. Results show that the mechanical refining increased the size of the formed flocs and decreased the concentration of free small particles (with dimensions between 1 and 20 pm) as a consequence of the increased fibrillation and content of fines, which increased the capacity of the fibres to capture the mineral particles. High levels of refining were necessary for Pinus pulp to obtain cement retention values similar to those obtained by unrefined Eucalyptus pulp. This is due to the higher number of fibres per gram in Eucalyptus pulp than in Pinus pulp. Pulp refining improved the packing of the particles and, although decreased the drainage rate. it contributed to a less porous structure, which improved the microstructure of the composite. (C) 2009 Elsevier Ltd. All rights reserved.
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Helical nanofibers are successfully constructed from suitable self-assembling pseudopeptide-based molecular building blocks. The handedness of these nanofibers can be reversed by using mirror-imaged pseudopeptide-based building blocks. Straight nanofibers are also constructed by modulating the molecular and supramolecular structures by the proper choice of the stereochemical nature of the molecular scaffolds. This study demonstrates that molecular structure and chirality are not the only determining factors for tuning the morphology and chirality of nanostructures; the nature of the supramolecular structures formed from the corresponding molecular scaffolds also plays a key role in dictating the shape and chirality of nanostructures. Helical nanofibers are suitable templates for fabricating dipeptide-capped gold nanoparticles, indicating a possible use of these nanofibers in the construction of arrays of gold nanoparticles.
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In this study we explore the impact of a morphological deficit on syntactic comprehension. A self-paced listening task was designed to investigate passive sentence processing in typically developing (TD) children and children with Grammatical-Specific Language Impairment (G-SLI). Participants had to judge whether the sentence they heard matched a picture they were shown. Working within the framework of the Computational Grammatical Complexity Hypothesis, which stresses how different components of the grammar interact, we tested whether children were able to use phonotactic cues to parse reversible passive sentences of the form the X was verbed by Y We predicted that TD children would be able to use phonotactics to parse a form like touched or hugged as a participle, and hence interpret passive sentences correctly. This cue is predicted not be used by G-SLI children, because they have difficulty building complex morphological representations. We demonstrate that indeed TD, but not G-SLI, children are able to use phonotactics cues in parsing passive sentences. (C) 2006 Elsevier B.V. All rights reserved.
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The present thesis deals with the development of new branched polymer architectures containing hyperbranched polyglycerol. Materials investigated include hyperbranched oligomers, hyperbranched polyglycerols containing functional initiator-cores at the focal point, well-defined linear-hyperbranched block copolymers and also negatively charged hyperbranched polyelectrolytes.rnHyperbranched oligoglycerols (DPn = 7 and 14) have been synthesized for the first time. The materials show narrow polydispersity (Mw/Mn ca. 1.45) and a very low content in cyclic homopolymers. 13C NMR evidences the dendritic structure of the oligomers and the DB could be calculated (44% and 52%). These new oligoglycerols were compared with the industrial products obtained by polycondensation which exhibit narrow polydispersity (Mw/Mn<1.3) butrnmultimodal distribution in SEC. Detailed 13C NMR and Maldi-ToF studies reveal the presence of branched units and cyclic compounds. In comparison, the hyperbranched oligoglycerols comprise a very low proportion of cyclic homopolymer which render them very interesting materials for biomedical applications for example.rnThe site isolation of the core moiety in dendritic structure offers intriguing potential with respect to peculiar electro-optical properties. Various initiator-cores (n-alkyl amines, UVabsorbing amines and benzophenone) for the ROMBP of glycidol have been tested. The bisglycidolized amine initiator-cores show the best control over the molecular weight and the molecular weight distribution. The photochemical analyses of the naphthalene containingrnhyperbranched polyglycerols show a slight red shift, a pronounced hypochromic effect (decrease of the intensity of the band) compared with the parent model compound and the formation of a relative compact structure. The benzophenone containing polymers adopt an open structure in polar solvents. The fluorescence measurements show a clear “dendritic effect” on the fluorescence intensities and the quantum yield of the encapsulated benzophenone.rnA convenient 3-step strategy has been developed for the preparation of well-defined amphiphilic, linear-hyperbranched block copolymers via hypergrafting. The procedure represents a combination of carbanionic polymerization with the alkoxide-based, controlled ring-opening multibranching polymerization of glycidol. Materials consisting of a polystyrene linear block and a hyperbranched polyglycerol block exhibit narrow polydispersity (1.01-1.02rnfor 5.4% to 27% wt. PG and 1.74 for 52% wt. PG) with a high grafting efficiency. The strategy was also extended to materials with a linear polyisoprene block.rnDetailed investigations of the solution properties of the block copolymers with linear polystyrene blocks show that block copolymer micelles are stabilized by the highly branched block. The morphology of the aggregates is depending on the solvent: in chloroform monodisperse spherical shape aggregates and in toluene ellipsoidal aggregates are formed. On graphite these aggregates show interesting features, giving promising potential applications with respect to the presence of a very dense, functional and stable hyperbranched block.rnThe bulk morphology of the linear-hyperbranched block copolymers has been investigated. The materials with a linear polyisoprene block only behave like complex liquids due to the low Tg and the disordered nature of both components. For the materials with polystyrene, only the sample with 27% wt. hyperbranched polyglycerol forms some domains showing lamellae.rnThe preparation of hyperbranched polyelectrolytes was achieved by post-modification of the hydroxyl groups via Michael addition of acrylonitrile, followed by hydrolysis. In aqueous solution materials form large aggregates with size depending on the pH value. After deposition on mica the structures observed by AFM show the coexistence of aggregates andrnunimers. For the low molecular weight sample (PG 520 g·mol-1) extended and highly ordered terrace structures were observed. Materials were also successfully employed for the fabrication of composite organic-inorganic multilayer thin films, using electrostatic layer-bylayer self-assembly coupled with chemical vapor deposition.
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Present research is framed within the project MODIFICA (MODelo predictivo - edIFIcios - Isla de Calor Urbana) aimed at developing a predictive model for dwelling energy performance under the urban heat island effect in order to implement it in the evaluation of real energy demand and consumption of dwellings as well as in the selection of energy retrofitting strategies. It is funded by Programa de I+D+i orientada a los retos de la sociedad 'Retos Investigación' 2013. The scope of our predictive model is defined by the heat island effect (UHI) of urban structures that compose the city of Madrid. In particular, we focus on the homogeneous areas for urban structures with the same urban and building characteristics. Data sources for the definition of such homogeneous areas were provided by previous research on the UHI of Madrid. The objective is to establish a critical analysis of climate records used for energy simulation tools, which data come from weather stations placed in decontextualized areas from the usual urban reality, where the thermal conditions differs by up to 6ºC. In this way, we intend to develop a new predictive model for the consumption and demand in buildings depending on their location, the urban structure and the associated UHI, improving the future energy rehabilitation interventions
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The use of electrocardiogram as biometric has raised attention in the last decade and a wide variety of ECG features were explored to verify the feasibility of such a signal. In this work the authors aim to describe a simple template based approach to the electrocardiographic biometric identification using the morphology of individual's heartbeat. The developed algorithm was tested on different recordings made available in the Physionet public database Fantasia: two different sets of heartbeats were extracted from individual recordings one was used for the template building while the second for the tests. The performances of the algorithm are encouraging with a true acceptance rate of 99.4%, however, the procedure needs to be tested on different recordings of the same individual, or during the course of a whole day or physical activity. © 2013 IEEE.
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Tese de Doutoramento, Biologia (Ciências do Mar), 5 de Julho de 2013, Universidade dos Açores.
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The aim was to evaluate the relationship between orofacial function, dentofacial morphology, and bite force in young subjects. Three hundred and sixteen subjects were divided according to dentition stage (early, intermediate, and late mixed and permanent dentition). Orofacial function was screened using the Nordic Orofacial Test-Screening (NOT-S). Orthodontic treatment need, bite force, lateral and frontal craniofacial dimensions and presence of sleep bruxism were also assessed. The results were submitted to descriptive statistics, normality and correlation tests, analysis of variance, and multiple linear regression to test the relationship between NOT-S scores and the studied independent variables. The variance of NOT-S scores between groups was not significant. The evaluation of the variables that significantly contributed to NOT-S scores variation showed that age and presence of bruxism related to higher NOT-S total scores, while the increase in overbite measurement and presence of closed lip posture related to lower scores. Bite force did not show a significant relationship with scores of orofacial dysfunction. No significant correlations between craniofacial dimensions and NOT-S scores were observed. Age and sleep bruxism were related to higher NOT-S scores, while the increase in overbite measurement and closed lip posture contributed to lower scores of orofacial dysfunction.
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Energy dispersive X-ray spectroscopy microanalysis (EDX), scanning electron microscopy (SEM), and Archimedes' Principle were used to determine the characteristics of inorganic filler particles in five dental alginates, including Cavex ColorChange (C), Hydrogum 5 (H5), Hydrogum (H), Orthoprint (O), and Jeltrate Plus (JP). The different alginate powders (0.5 mg) were fixed on plastic stubs (n = 5) and sputter coated with carbon for EDX analysis, then coated with gold, and observed using SEM. Volume fractions were determined by weighing a sample of each material in water before and after calcining at 450(°)C for 3 h. The alginate materials were mainly composed of silicon (Si) by weight (C-81.59%, H-79.89%, O-78.87%, H5-77.95%, JP-66.88%, wt). The filler fractions in volume (vt) were as follows: H5-84.85%, JP-74.76%, H-70.03%, O-68.31%, and C-56.10%. The tested materials demonstrated important differences in the inorganic elemental composition, filler fraction, and particle morphology.