49 resultados para Climatic conditions


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Parametric modelling is gaining in popularity as both a fabrication and design tool, but its application in the architectural design industry has not been widely explored. Parametric modelling has the ability to generate complex forms with intuitively reactive components, allowing designers to express and fabricate structures previously too laborious and geometrically complex to realise. This alIows designers to address a project at both the macro and micro levels of resolution in the governing control surface and the individual repetitive component. This two level modelling control, of component and overall surface, can allow designers to explore new types of form generation subject to parametric constraints. Shading screens have been selected as the focus for this paper and are used as a medium to explore form generation within a given set of functional parameters. Screens can have many applications in a building but for the purpose of the following case studies, lighting quality and passive sun control are the main functional requirement. A set of screen components have been designed within certain shading parameters to create a generic component that can automatically adapt to any given climatic conditions. These will then be applied to surfaces of varying degrees of geometric complexity to be analysed in their ability to correctly tessellate and create a unified screening array true to the lighting requirements placed on the generic component.

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The market is an essential component of urban form. Contemporary shopping malls can benefit from the inherent efficiencies of traditional markets. This paper addresses the development of sustainable models of market typologies based on a specific case study, the Bazaar of Tabriz in Iran.

As one of the biggest historical covered markets in the world (Moradi and Nassabi 2007), it remains an effective trading centre in the city. What are the lessons that make Tabriz a sustainable urban typology and what lessons can we draw from its spatial and operational structure?

To address this question, the paper presents two analytical studies of the urban and building morphology of Tabriz. First, the paper presents an analysis of the urban and social structure of the market based on Lynchian analysis. Second, it provides an analysis of the thermal, ventilation and lighting principles used in the buildings of the market and how they respond to the extreme climatic conditions of north-west Iran.

Rainfall and snow in one side and hot summers in the other, give the buildings in the city really critical performance in terms of life span during the years of operation.

The main target in this case study, is to illuminate the urban typological clarifications in the Bazaar of Tabriz, which wilt elucidate how parallel links between urban morphology (land cover) and urban typology (land use) in a defined urban planning can form a sustainable urban space. Moreover, how the case of this study can be an energy efficient complex with its own urban morphology.

The lessons of Tabriz for the development of contemporary markets are summarised in the paper and need to be addressed at two scales, namely the urban scale and the scale of the building.

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Vernacular dwelling buildings located in hot arid regions are well known for their sensitive architecture response to the region’s climatic conditions and the socio-cultural norms. The architectural value of these buildings is not only limited to their historical merit, but also to the human conscious adaptation to its context and the optimum utilisation of natural resources creating both a pleasant and a functional environment. The majority of these traditional dwellings are well recognised for their unique perforated fenestration system and courtyard arrangement that evolved to control the harsh solar, climatic conditions without compromising the quality of space and occupants’ wellbeing. However, the successful design of these features and solutions cannot be fully appreciated without understanding the nature of daylight and solar radiation in which these buildings are revealed. This paper investigates the impact of the characteristic of the dense narrow streets of medieval cities on the visual performance of a typical courtyard house in Cairo.The paper examines the daylight  behaviour of one of the well-known historic alleys and of a courtyard house in Cairo. The paper analyzes and measures the variability in the visual perception and comfort for a typical pedestrian street and the occupants of the house using a simulation modelling tool (Integrated Environmental Solutions (IES) software). The paper gives an insight into the overall visual performance of the urban fabric that shapes of the microclimate, which is an important ingredient of the overall identity of the place.

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The future impacts of climate change are predicted to significantly affect the survival of many species. Recent studies indicate that even species that are relatively mobile and/or have large geographic ranges may be at risk of range contractions or extinction. An ecologically and evolutionary significant group of mammals that has been largely overlooked in this research is Australia’s large marsupial herbivores, the macropodids (kangaroos). The aims of our investigation were to define and compare the climatic conditions that influence the current distributions of four sympatric large macropodids in northern Australia (Macropus antilopinus, Macropus robustus, Macropus giganteus, and Macropus rufus) and to predict the potential future impact of climate change on these species. Our results suggest that contemporary distributions of these large macropodids are associated with well‐defined climatic gradients (tropical and temperate conditions) and that climatic seasonality is also important. Bioclimatic modeling predicted an average reduction in northern Australian macropodid distributions of in response to increases of 2.0°C. At this temperature, the distribution of M. antilopinus was reduced by . We predict that increases of 6.0°C may cause severe range reductions for all four macropodids ( ) in northern Australia, and this range reduction may result in the extinction of M. antilopinus.

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Determining the biological and environmental factors that limit the distribution and abundance of organisms is central to our understanding of the niche concept and crucial for predicting how species may respond to large-scale environmental change, such as global warming. However, detailed ecological information for the majority of species has been collected only at a local scale, and insufficient consideration has been given to geographical variation in intraspecific niche requirements. To evaluate the influence of environmental and biological factors on patterns of species distribution and abundance, we conducted a detailed, broadscale study across the tropical savannas of northern Australia on the ecology of three large, sympatric marsupial herbivores (family Macropodidae): the antilopine wallaroo (Macropus antilopinus), common wallaroo (M. robustus), and eastern grey kangaroo (M. giganteus). Using information on species abundance, climate, fire history, habitat, and resource availability, we constructed species' habitat models varying from the level of the complete distribution to smaller regional areas. Multiple factors affected macropod abundance, and the importance of these factors was dependent on the spatial scale of analyses. Fire regimes, water availability, geology, and soil type and climate were most important at the large scale, whereas aspects of habitat structure and interspecific species abundance were important at smaller scales. The distribution and abundance of eastern grey kangaroos and common wallaroos were strongly influenced by climate. Our results suggest that interspecific competition between antilopine wallaroos and eastern grey kangaroos may occur. The antilopine wallaroo and eastern grey kangaroo (grazers) preferred more nutrient-rich soils than the common wallaroo (grazer/browser), which we relate to differences in feeding modes. The abundance of antilopine wallaroos was higher on sites that were burned, whereas the abundance of common wallaroos was higher on unburned sites. Future climate change predicted for Australia has the capacity to seriously affect the abundance and conservation of macropod species in tropical savannas. The results of our models suggest that, in particular, the effects of changing climatic conditions on fire regimes, habitat structure, and water availability may lead to species declines and marked changes in macropod communities.


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Climatic conditions in Australia are erratic and characterised by periods of intense rainfall followed by periods of intense drought. This has considerable impact on the population dynamics and ecology of many Australian species of waterfowl, which are thought to form the reservoir of avian influenza viruses (AIV) but may also be important carriers (and possibly reservoirs) of other diseases (e.g. bursal disease, Newcastle disease). During the wet, waterfowl numbers increase with many serologically naive juveniles entering the population. During the subsequent period of drought, bird densities increase in the few remaining wetlands. We hypothesise that it is during this period of increasing densities of naive birds that the population’s viral prevalence of some infectious diseases may increase dramatically. Indeed, there exists a remarkable and suggestive coincidence between outbreaks of fowl plaque and Newcastle disease in Australian poultry farms and the periods of drought following a very wet period. In other words, we suspect a link between increased risk for disease outbreaks in poultry farms and the hypothesised high in the prevalences of the viruses causing these diseases in waterfowl. Given that poultry farms may provide ideal conditions for development of high-pathogenic strains, there is also a reciprocal risk for wildlife involved during these periods.

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Traditional dwellings located in the hot arid zones of the Arabian regions are well known for their sensitive architectural response to the region’s climatic conditions and socio-cultural norms. The majority of these dwellings are well recognized for their courtyard arrangement and perforated fenestration system that evolved to control the harsh solar, climatic conditions without compromising the aesthetic quality of space and occupants’ wellbeing. However, the unique visual characteristics of these structures cannot be fully appreciated by assessing the visual performance of buildings in isolation from their urban context. Given the fact that much of the character of the traditional settlements of this region came from the collective visual perception of their architectural components as well as urban patterns. This paper presents a methodology that can be used to assess daylight behaviour at an architectural level as well as at an urban scale. The work examines the daylight behaviour of a well-known historic alleyway and of a courtyard house in the old city of Cairo. The variability in the visual perception and comfort for a typical pedestrian street and the occupants of the house was predicted using Radiance IES simulation modelling tool and a scaled model under an artificial sky dome. A comparative analysis between simulated results and measured values at target points was conducted and the results reveal a reasonable agreement with the simulation results. Preliminary results from the first phase of modelling were presented that give an insight into the overall visual experience in the traditional settlements in the Old City of Cairo where daylight has contributed to the place unique sense of identity.

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A collection of images examining the microstructure of raw cocoons. The research investigates how the microstructure varies from one layer to another in the same cocoon and also from one cocoon variety to another. The research is being undertaken to study the structure and property relationships, specifically the antibacterial properties, photodegradability and mechanical strength of different cocoon components - fibre, sericin, and crystals. The aim is to understand the role of different cocoon components and their mechanism of protecting the pupa from extremes of climatic conditions, microorganisms, and other pathogens and predators. Scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) were used to analyse the structure of the cocoons, fibre, and sericin.

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American bison grow a thick coat of fibres which assists them to withstand severe climatic conditions. Bison fibre was traditionally used in textiles by native North Americans. This study aimed to quantify the production, fibre attributes and dehairing processing of bison fibre produced from bison grazed in north-eastern Victoria. Three age/sex classes were sampled (n = 16) at seven body positions in spring. The fibre growing area was measured. Fibre was tested for diameter distribution, clean washing yield, proportion of fine fibres <36µm and fine fibre length, and processed by cashmere dehairing. Bison were 12 years of age, liveweights 160450 kg and had mean fibre growing area of 1.4 m2. They produced an average 1184 g (range 5301640 g) of fine fibre with mean fibre diameter 18.5µm, clean washing yield 76.5%, wax content 9.8%, suint content 14.5%, clean fine fibre yield 56.4%, fine fibre length 37 mm and fibre curvature was 93/mm. Mid-side fibre had a crimp frequency of 6.5/cm and mean resistance to compression of 6.6 kPa. Fibre had a tenacity of 8.7 cN/tex and an extension of 39.3%. Restricted maximum likelihood mixed model analysis showed age/sex class and sampling site significantly affected all fibre attributes. Finer and longer fibre was produced in anterior sites and in younger bison. Fibre curvature declined 5.3°/mm for each 1-µm increase in mean fibre diameter. Dehaired fibre had a mean fibre diameter of 17.8 µm and mid-length of 28 mm, suitable for woollen spinning. The production by bison of coats containing significant amounts of fibre indicates that careful harvesting of fibre could form an important source of income in bison enterprises.

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Traditional dwellings located in the hot arid zone in Egypt are well known for their sensitive architectural response to the region's climatic conditions and socio-cultural norms. The majority of these dwellings are well recognized for their courtyard arrangement and perforated fenestration systems that evolved to control the harsh solar, climatic conditions without compromising the aesthetic quality of the space and the occupants' well-being. The unique visual characteristics of these structures cannot be fully appreciated by assessing the visual performance of buildings in isolation from their urban context. Much of the character of the traditional urban fabric of this region came from the collective visual perception of its architectural components as well as urban patterns. This paper examines daylight behavior of a well-known historic alleyway and of a courtyard house in the Old City of Cairo. Using the Radiance IES simulation modeling tool and a scaled model under an artificial sky dome, the paper investigates the visual comfort in a typical pedestrian street and a selected house. A comparative analysis between simulated results and measured values at target points was conducted. The results indicate a reasonable agreement with the simulation results. The paper gives an insight into the overall visual experience in the traditional settlements in the Old City of Cairo in relation to daylight components and hence their contribution to the unique sense of identity of the place.

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While white cashmere is preferred by processors, its whiteness and brightness is affected by country of origin, amino acid composition, nutrition and cashmere production of goats. This work aimed to quantify the factors which affect the whiteness and brightness of 36 batches of processed Australian white cashmere sourced from nine different farms. The cashmere was tested for tristimulus values brightness (Y) and whiteness, as measured by yellowness (Y-Z). Linear models, relating Y and Y-Z were fitted to farm of origin and other objective measurements. Mean attributes (range) were: mean fibre diameter, 16.9 µm (13.9–20.4 μm); fibre curvature, 45°/mm (31–59°/mm); clean washing yield, 91.3% (79.5–97.3%); Y, 78.7 (74.7–82.2); Y-Z, 11.9 (10.3–13.6). Farm alone accounted for 72% of the variation in Y and 65% of the variation in Y-Z (P < 0.001). Once farm had been taken into account only fibre curvature (P = 0.003) was significant in predicting Y and only clean washing yield (P = 0.047) affected Y-Z. Neither the proportion of the fleece present as guard hair (clean cashmere yield) nor cashmere staple length was a significant determinant of Y or Y-Z. For each 10°/mm increase in fibre curvature Y increased 1.3 units. For each 10% increase in clean washing yield Y-Z declined 0.9 units. Variations in Y and Y-Z among farms were probably related to differences in geographic and climatic conditions and were significantly correlated to cashmere production. The effect of clean washing yield was probably related to a reduction in suint content.


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Food security is a significant issue in the remote, high altitude areas of Nepal. Malnutrition is common because the harsh climate restricts production and access to fresh food. Humla is a province in north-west Nepal where the severe weather conditions and limited arable land restrict the growing season of vegetables to only 4-5 months a year. Passive solar greenhouses are a technology that can be used to extend the growing period of vegetables. For the greenhouse to be effective in Humla, the design must be appropriate to the climatic conditions, available resources and the social requirements of the community. This paper describes the design and evaluation of a family-sized solar greenhouse proposed for Humla. Three solar greenhouses built in other high altitude areas have initially been reviewed to see what techniques might be replicated in Humla. The thermal performance of the proposed family-sized greenhouse has been predicted using the solar simulation software, TRNSYS, and compared against an existing design in the area. The proposed design was found to be superior and average night-time temperatures in the coldest month were predicted to be approximately 7°C higher. Overheating was controlled in the hottest month by shading and natural ventilation.

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The outdoor places are receiving more importance being contributing in the social cohesion and sustainability within societies. Providing comfortable sustainable urban places is an important factor affecting their success especially in multicultural areas where climatic conditions are perceived differently according to the diversity of users. Different design elements such as design form proved to be able to improve the outdoor thermal comfort. However, the integration of the climate dimension in the design process of outdoor places is lacking due to insufficient interdisciplinary work between urban climatology, and urban design. The main aim of the research is to examine the influence of cultural and climatic background on users’ thermal sensation and comfort within the same context. The methodology of the research is provided through quantitative analysis of a case study in Melbourne, Australia as one of the global cities characterized by the diversity and plurality of its population. The case study approach is adopted in order to examine the users’ thermal comfort within its contextual variables. Multiple sources of evidence such as climate measurements, questionnaires and observations are used to ensure the validity of results. The findings are to contribute to the quality and equality of design for outdoor urban places.

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Thermal comfort in outdoor places has proven to have a strong relationship with their users’ attendance and behaviour [1]. Creating comfortable places is therefore to be considered a crucial part of the design process, as taking it into consideration help increasing the social integration between people and therefore fosters sustainability within cities [2]. With the increasing number of migrants within global cities, a new challenge has been facing thermal comfort studies. This challenge is related to the different cultural and climatic origins of those migrants and how they can adapt to the new climatic conditions they are to move in. This paper aims to explore the impact of thermal comfort adaptation on users’ thermal perception in multicultural cities. Consequently, a quantitative field study is applied in Melbourne city, Australia in order to investigate peoples’ outdoor thermal comfort. The analyses were based upon the measurement of climatic parameters that were monitored simultaneously with a questionnaire to determine users’ thermal comfort perception in relation to their time spent in the city. The findings of thermal comfort investigations could be applied into improving the quality of urban areas within global cities and therefore promote the integration within individuals in those societies.

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A key task in ecology is to understand the drivers of animal distributions. In arid and semi-arid environments, this is challenging because animal populations show considerable spatial and temporal variation. An effective approach in such systems is to examine both broad-scale and long-term data. We used this approach to investigate the distribution of small mammal species in semi-arid ‘mallee’ vegetation in south-eastern Australia. First, we examined broad-scale data collected at 280 sites across the Murray Mallee region. We used generalized additive mixed models (GAMMs) to examine four hypotheses concerning factors that influence the distribution of individual mammal species at this scale: vegetation structure, floristic diversity, topography and recent rainfall. Second, we used long-term data from a single conservation reserve (surveyed from 1997 to 2012) to examine small mammal responses to rainfall over a period spanning a broad range of climatic conditions, including record high rainfall in 2011. Small mammal distributions were strongly associated with vegetation structure and rainfall patterns, but the relative importance of these drivers was species-specific. The distribution of the mallee ningaui Ningaui yvonneae, for example, was largely determined by the cover of hummock grass; whereas the occurrence of the western pygmy possum Cercartetus concinnus was most strongly associated with above-average rainfall. Further, the combination of both broad-scale and long-term data provided valuable insights. Bolam's mouse Pseudomys bolami was uncommon during the broad-scale survey, but long-term surveys showed that it responds positively to above-average rainfall. Conceptual models developed for small mammals in temperate and central arid Australia, respectively, were not, on their own, adequate to account for the distributional patterns of species in this semi-arid ecosystem. Species-specific variation in the relative importance of different drivers was more effectively explained by qualitative differences in life-history attributes among species.