201 research outputs found

    Learning to Chill: The Role of Design Schools and Professional Training to Improve Urban Climate and Urban Metabolism

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    The increased frequency of heat-related mortality and morbidity in urban environments indicates the importance of urban climate studies. As most of the world’s population lives in cities, the education of designers, planners and policy makers is crucial to promote urban sustainability This paper, firstly, focuses on the different factors causing the urban heat islands in large cities. Secondly, it considers how these factors are reflected in higher education programmes. Examples are shown from courses in UK higher education, explaining the common software tools used for simulating urban spaces, and student field measurements are drawn on to illustrate how urban climate studies are included in higher education curricula. Urban metabolism is used to conceptualise the main approach to systemic resource-use assessments and as a holistic framework to investigate the main drivers of the urban heat island phenomenon. To sum up, this paper reflects on the importance of training climatically-aware graduates from design schools

    Energy performance and thermal comfort of courtyard/atrium dwellings in the Netherlands in the light of climate change

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    With increased global concerns on climate change, the need for innovative spaces which can provide thermal comfort and energy efficiency is also increasing. This paper analyses the effects of transitional spaces on energy performance and indoor thermal comfort of low-rise dwellings in the Netherlands, at present and projected in 2050. For this analysis the four climate scenarios for 2050 from the Royal Dutch Meteorological Institute (KNMI) were used. Including a courtyard within a Dutch terraced dwelling on the one hand showed an increase in annual heating energy demand but on the other hand a decrease in the number of summer discomfort hours. An atrium integrated into a Dutch terraced dwelling reduced the heating demand but increased the number of discomfort hours in summer. Analysing the monthly energy performance, comfort hours and the climate scenarios indicated that using an open courtyard May through October and an atrium, i.e. a covered courtyard, in the rest of the year establishes an optimum balance between energy use and summer comfort for the severest climate scenario

    Indoor thermal comfort in urban courtyard block dwellings in the Netherlands

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    Global warming and elevated temperatures in the Netherlands will increase the energy demand for cooling. Studying passive strategies to cope with the consequences of climate change is inevitable. This paper investigates the thermal performance of courtyard dwellings in the Netherlands. The effects of different orientations and elongations, cool roofs and pavements on indoor thermal comfort are studied through simulations and field measurements. The results show that North-South and East-West orientations provide the least and most comfortable indoor environments. Regarding materials, the use of green on roofs and as courtyard pavement is the most effective heat mitigation strategy. It was observed that the effects of wet cool roofs are much higher than of dry roofs. Cool roofs did not show a specific negative effect (heat loss) as compared to conventional asphalt roofs in winter. Some simulation results were validated through field measurement with a 0.91°C root mean square deviation

    Heat in courtyards : a validated and calibrated parametric study of heat mitigation strategies for urban courtyards in the Netherlands

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    Outdoor thermal comfort in urban spaces is an important contributor to pedestrians’ health. A parametric study into different geometries and orientations of urban courtyard blocks in the Netherlands was therefore conducted for the hottest day in the Dutch reference year (19th June 2000 with the maximum 33 °C air temperature). The study also considered the most severe climate scenario for the Netherlands for the year 2050. Three urban heat mitigation strategies that moderate the microclimate of the courtyards were investigated: changing the albedo of the facades of the urban blocks, including water ponds and including urban vegetation. The results showed that a north–south canyon orientation provides the shortest and the east–west direction the longest duration of direct sun at the centre of the courtyards. Moreover, increasing the albedo of the facades actually increased the mean radiant temperature in a closed urban layout such as a courtyard. In contrast, using a water pool and urban vegetation cooled the microclimates; providing further evidence of their promise as strategies for cooling cities. The results are validated through a field measurement and calibration

    Heat mitigation strategies in winter and summer: Field measurements in temperate climates

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    Natural elements such as vegetation and water bodies may help reduce heat in urban spaces in summer or in hot climates. This effect, however, has rarely been studied during cold seasons. This paper briefly studies the effect of vegetation and water in summer and more comprehensively in winter. Both studies are done in courtyards on two university campuses in temperate climates. A scale model experiment with similar materials supports the previous studies. The summer study is done in Portland (OR), USA, and the winter study (along with the scale model) in Delft, the Netherlands. The summer study shows that a green courtyard at most has a 4.7 °C lower air temperature in the afternoon in comparison with a bare one. The winter study indicates that the air temperature above a green roof is higher than above a white gravel roof. It also shows that, although a ‘black’ courtyard has higher air temperatures for a few hours on sunny winter days, a courtyard with a water pond and with high amounts of thermal mass on the ground has a warmer and more constant air temperature in general. Both the summer and winter studies show that parks in cities have a lower and more constant air temperature compared to suburbs, both in summer and winter. The scale model also demonstrates that although grass has a lower albedo than the used gravel, it can provide a cooler environment in comparison with gravels and black roof

    Thermal assessment of heat mitigation strategies : the case of Portland State University, Oregon, USA

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    Courtyard vegetation, high albedo surfaces, and courtyard ponds were investigated as potential heat mitigation strategies using field measurements and simulations in a university campus environment. The investigation was performed during a summer period in the temperate climate of Portland, Oregon, USA. In a comparison of seven locations on the campus, the maximum park cooling island effect recorded was 5.8 °C between the heavily treed campus park and a nearby parking lot with asphalt pavement. Simulations of courtyards with vegetation and a water pond showed 1.6 °C and 1.1 °C air temperature reduction, respectively. Changing the albedo of the pavement in a bare courtyard from 0.37 (black) to 0.91 (white) led to 2.9 °C increase of mean radiant temperature and 1.3 °C decrease of air temperature

    Outdoor thermal comfort within five different urban forms in the Netherlands

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    Outdoor thermal comfort in urban spaces is known as an important contributor to pedestrians' health. The urban microclimate is also important more generally through its influence on urban air quality and the energy use of buildings. These issues are likely to become more acute as increased urbanisation and climate change exacerbate the urban heat island effect. Careful urban planning, however, may be able to provide for cooler urban environments. Different urban forms provide different microclimates with different comfort situations for pedestrians. In this paper, singular East–West and North–South, linear East–West and North–South, and a courtyard form were analysed for the hottest day so far in the temperate climate of the Netherlands (19th June 2000 with the maximum 33 °C air temperature). ENVI-met was used for simulating outdoor air temperature, mean radiant temperature, wind speed and relative humidity whereas RayMan was used for converting these data into Physiological Equivalent Temperature (PET). The models with different compactness provided different thermal environments. The results demonstrate that duration of direct sun and mean radiant temperature, which are influenced by urban form, play the most important role in thermal comfort. This paper also shows that the courtyard provides the most comfortable microclimate in the Netherlands in June compared to the other studied urban forms. The results are validated through a field measurement and calibration

    The impact of heat mitigation strategies on the energy balance of a neighborhood in Los Angeles

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    Heat mitigation strategies can reduce excess heat in urban environments. These strategies, including solar reflective cool roofs and pavements, green vegetative roofs, and street vegetation, alter the surface energy balance to reduce absorption of sunlight at the surface and subsequent transfer to the urban atmosphere. The impacts of heat mitigation strategies on meteorology have been investigated in past work at the mesoscale and global scale. For the first time, we focus on the effect of heat mitigation strategies on the surface energy balance at the neighborhood scale. The neighborhood under investigation is El Monte, located in the eastern Los Angeles basin in Southern California. Using a computational fluid dynamics model to simulate micrometeorology at high spatial resolution, we compare the surface energy balance of the neighborhood assuming current land cover to that with neighborhood‐wide deployment of green roof, cool roof, additional trees, and cool pavement as the four heat mitigation strategies. Of the four strategies, adoption of cool pavements led to the largest reductions in net radiation (downward positive) due to the direct impact of increasing pavement albedo on ground level solar absorption. Comparing the effect of each heat mitigation strategy shows that adoption of additional trees and cool pavements led to the largest spatial‐maximum air temperature reductions at 14:00h (1.0 and 2.0 °C, respectively). We also investigate how varying the spatial coverage area of heat mitigation strategies affects the neighborhood‐scale impacts on meteorology. Air temperature reductions appear linearly related to the spatial extent of heat mitigation strategy adoption at the spatial scales and baseline meteorology investigated here

    Risk assessment of drug management process in women surgery department of qaem educational hospital (QEH) using HFMEA method (2013)

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    Evaluation and improvement of drug management process are essential for patient safety. The present study was performed whit the aim of assessing risk of drug management process in Women Surgery Department of QEH using HFMEA method in 2013. A mixed method was used to analyze failure modes and their effects with HFMEA. To classify failure modes; nursing errors in clinical management model, for classifying factors affecting error; approved model by the UK National Health System, and for determining solutions for improvement; Theory of Inventive Problem Solving, were used. 48 failure modes were identified for 14 sub-process of five steps drug management process. The frequency of failure modes were as follow:35.3 in supplying step, 20.75 in prescription step, 10.4 in preparing step, 22.9 in distribution step and 10.35 in follow up and monitoring step. Seventeen failure modes (35.14) were considered as non-acceptable risk (hazard score� 8) and were transferred to decision tree. Among 51 Influencing factors, the most common reasons for error were related to environmental factors (21.5), and the less common reasons for error were related to patient factors (4.3). HFMEA is a useful tool to evaluating, prioritization and analyzing failure modes in drug management process. Revision drug management process based focus-PDCA, assessing adverse drug reactions (ADR), USE patient identification bracelet, holding periodical pharmaceutical conferences to improve personnel knowledge, patient contribution in drug therapy; are performance solutions which were placed in work order. © 2015 by School of Pharmac

    Solar Sail Topology Variations Due to On-Orbit Thermal Effects

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    The objective of this research was to predict the influence of non-uniform temperature distribution on solar sail topology and the effect of such topology variations on sail performance (thrust, torque). Specifically considered were the thermal effects due to on orbit attitude control maneuvers. Such maneuvers are expected to advance the sail to a position off-normal to the sun by as much as 35 degrees; a solar sail initially deformed by typical pre-tension and solar pressure loads may suffer significant thermally induced strains due to the non-uniform heating caused by these maneuvers. This on-orbit scenario was investigated through development of an automated analytical shape model that iterates many times between sail shape and sail temperature distribution before converging on a final coupled thermal structural affected sail topology. This model utilizes a validated geometrically non-linear finite element model and a thermal radiation subroutine. It was discovered that temperature gradients were deterministic for the off-normal solar angle cases as were thermally induced strains. Performance effects were found to be moderately significant but not as large as initially suspected. A roll torque was detected, and the sail center of pressure shifted by a distance that may influence on-orbit sail control stability
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