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Tariq Muneer - One of the best experts on this subject based on the ideXlab platform.

  • Sol-air temperature and daylight illuminance profiles for the UKCP09 data sets
    Building and Environment, 2011
    Co-Authors: Yieng Wei Tham, Tariq Muneer
    Abstract:

    Abstract To provide information on climate change, the UK Climate Impacts Programme (UKCIP) provided the latest UKCP09 data to a resolution of 5 km square grids for the UK. Those data sets were used in this study along with the historical measured data for two locations—Bracknell (London) and Edinburgh—to critically analyse the likely changes that may occur in the sol-air temperature and daylight illuminance profiles. These parameters have an important bearing on the design and function of buildings and building services. Drastic increment of sol-air temperature was found for the projected data sets. An increase of as much as 20.1 °C of sol-air temperature for dark-coloured surface was found for Edinburgh and 13.3 °C for Bracknell. These increments may be due to the compound effect of change in the constituent variables that are used to calculate sol-air temperature, i.e. solar radiation, wind speed and dry bulb temperature. A sensitivity test was carried out to see the effect of each variable on sol-air temperature. An increasing trend of daylight was also found in the data sets. This is attributed to the changing clarity of the sky condition. The predictions indicate a radical change in the characteristics of solar climate, i.e. from the present diffuse fraction of total irradiation of 0.37 which indicates mild turbidity to a drop of 0.13 indicating clear skies with exceptionally low turbidity.

  • An examination of UKCIP CP02 and CP09 data sets for the UK climate related to their use in building design.
    2011
    Co-Authors: Yieng Wei Tham, Tariq Muneer, Geoff Levermore, David Chow
    Abstract:

    The climate is changing, both globally and in the UK. To adapt effectively, engineers and planners need as much information as possible on how the climate will evolve. The UK Climate Impacts Programme (UKCIP) provided this in 2002 with UKCIP02 and the latest data UKCP09, which provides data to a resolution of 5 km square grids over the UK. Data sets from these were used in this study along with the historical measured data for three locations -- Bracknell (London), Manchester and Edinburgh -- to analyse critically the likely changes that may occur in the key climate variables, that is temperature, sunshine duration and solar irradiation. These parameters have an important bearing on the design and function of buildings and building services. Sunshine duration is the main variable that is used to obtain solar radiation in the UKCP09 5 km grid data. For the grids containing Bracknell, Manchester and Edinburgh, most of the UKCP09 data sets for the years 2050 and 2080 showed abnormally elongated sunshine duration, that is from sunrise to sunset, for clear days. In contrast, the latest historic measured data sets indicate only a third of the above sunshine duration. Note that the latter data are used in cooling load design calculations and for the generation of sol-air temperatures.1 Of particular note was the anomalous occurrence in UKCP09 of late evening sunshine duration. For Bracknell and Edinburgh, the sunshine duration at hour ending 20 and beyond showed substantial amount of predicted sunshine. As a result of this work, corrective action has been proposed for UKCP09 data. Furthermore, a very significant increase was also noted in solar irradiation for UKCP09. For the historic measured data for Bracknell, the clear day noon irradiation is 818 Wh/m 2 . For the UKCP09 grid containing Bracknell the 2080 High Emission scenario data gives an average value of 1002 Wh/m2 , an increase of 23%. The same trend occurs for Edinburgh, (a present value of 789 Wh/m 2 and the predicted value of 948 Wh/m2 , an increase of 20%). Note that compounded with presently found increase of 4--5°C increase for the above locations, the substantial increase in irradiation will have a much more pronounced increase in the cooling load of buildings. An evaluation of the change in the character of solar radiation was also undertaken. This was done by noting the change in the diffuse fraction of global irradiation. For Bracknell and Edinburgh historic data and UKCP09 data 2080 High Emission data set show a drastic decrease, respectively from 0.37 to 0.13 and from 0.33 to 0.14. Diffuse fraction may be used as an indicator of the prevailing sky clarity. If the predictions come true a drastic decrease in the diffuse fraction of this magnitude signifies a radical shift in the character of solar climate for the future. The current solar climate of Bracknell is known for its above average turbidity, the latter stemming from the following factors: inland location, high-density housing, proximity to Heathrow airport and M25 London orbital motorway. Whether such an extreme shift in the sky clarity will occur within a matter of 60--70 years is open to discussion. Practical applications: To adapt effectively against the challenge posed by climate change engineers need to know the extent to which the basic climate variables such as temperature and solar radiation will change. This work has used basic data from the UKCP09 project to analyse the extent of the above change with respect to the basic and other derived data. It was shown that for Scottish and English locations a temperature rise of up to 4--5°C may occur between the present age and the year 2080 for High Emission scenario. It was also shown that the corresponding irradiation strength may increase around 22%. Furthermore, it was also found that if these predictions come true then a drastic decrease in the diffuse fraction of irradiation will produce a radical shift in the character of solar climate. The resulting higher proportion of beam irradiation will have to be handled with care in design of overhangs and other shading contraptions to prevent an excessive increase in cooling load of buildings.

  • An examination of UKCIP02 and UKCP09 solar radiation data sets for the UK climate related to their use in building design
    Building Services Engineering Research and Technology, 2010
    Co-Authors: Yieng Wei Tham, Tariq Muneer, Geoff Levermore, David Chow
    Abstract:

    the UKCP09 grid containing Bracknell the 2080 High Emission scenario data gives an average value of 1002 Wh/m 2 , an increase of 23%. The same trend occurs for Edinburgh, (a present value of 789 Wh/m 2 and the predicted value of 948 Wh/m 2 , an increase of 20%). Note that compounded with presently found increase of 4–58C increase for the above locations, the substantial increase in irradiation will have a much more pronounced increase in the cooling load of buildings. An evaluation of the change in the character of solar radiation was also undertaken. This was done by noting the change in the diffuse fraction of global irradiation. For Bracknell and Edinburgh historic data and UKCP09 data 2080 High Emission data set show a drastic

Yieng Wei Tham - One of the best experts on this subject based on the ideXlab platform.

  • Sol-air temperature and daylight illuminance profiles for the UKCP09 data sets
    Building and Environment, 2011
    Co-Authors: Yieng Wei Tham, Tariq Muneer
    Abstract:

    Abstract To provide information on climate change, the UK Climate Impacts Programme (UKCIP) provided the latest UKCP09 data to a resolution of 5 km square grids for the UK. Those data sets were used in this study along with the historical measured data for two locations—Bracknell (London) and Edinburgh—to critically analyse the likely changes that may occur in the sol-air temperature and daylight illuminance profiles. These parameters have an important bearing on the design and function of buildings and building services. Drastic increment of sol-air temperature was found for the projected data sets. An increase of as much as 20.1 °C of sol-air temperature for dark-coloured surface was found for Edinburgh and 13.3 °C for Bracknell. These increments may be due to the compound effect of change in the constituent variables that are used to calculate sol-air temperature, i.e. solar radiation, wind speed and dry bulb temperature. A sensitivity test was carried out to see the effect of each variable on sol-air temperature. An increasing trend of daylight was also found in the data sets. This is attributed to the changing clarity of the sky condition. The predictions indicate a radical change in the characteristics of solar climate, i.e. from the present diffuse fraction of total irradiation of 0.37 which indicates mild turbidity to a drop of 0.13 indicating clear skies with exceptionally low turbidity.

  • An examination of UKCIP CP02 and CP09 data sets for the UK climate related to their use in building design.
    2011
    Co-Authors: Yieng Wei Tham, Tariq Muneer, Geoff Levermore, David Chow
    Abstract:

    The climate is changing, both globally and in the UK. To adapt effectively, engineers and planners need as much information as possible on how the climate will evolve. The UK Climate Impacts Programme (UKCIP) provided this in 2002 with UKCIP02 and the latest data UKCP09, which provides data to a resolution of 5 km square grids over the UK. Data sets from these were used in this study along with the historical measured data for three locations -- Bracknell (London), Manchester and Edinburgh -- to analyse critically the likely changes that may occur in the key climate variables, that is temperature, sunshine duration and solar irradiation. These parameters have an important bearing on the design and function of buildings and building services. Sunshine duration is the main variable that is used to obtain solar radiation in the UKCP09 5 km grid data. For the grids containing Bracknell, Manchester and Edinburgh, most of the UKCP09 data sets for the years 2050 and 2080 showed abnormally elongated sunshine duration, that is from sunrise to sunset, for clear days. In contrast, the latest historic measured data sets indicate only a third of the above sunshine duration. Note that the latter data are used in cooling load design calculations and for the generation of sol-air temperatures.1 Of particular note was the anomalous occurrence in UKCP09 of late evening sunshine duration. For Bracknell and Edinburgh, the sunshine duration at hour ending 20 and beyond showed substantial amount of predicted sunshine. As a result of this work, corrective action has been proposed for UKCP09 data. Furthermore, a very significant increase was also noted in solar irradiation for UKCP09. For the historic measured data for Bracknell, the clear day noon irradiation is 818 Wh/m 2 . For the UKCP09 grid containing Bracknell the 2080 High Emission scenario data gives an average value of 1002 Wh/m2 , an increase of 23%. The same trend occurs for Edinburgh, (a present value of 789 Wh/m 2 and the predicted value of 948 Wh/m2 , an increase of 20%). Note that compounded with presently found increase of 4--5°C increase for the above locations, the substantial increase in irradiation will have a much more pronounced increase in the cooling load of buildings. An evaluation of the change in the character of solar radiation was also undertaken. This was done by noting the change in the diffuse fraction of global irradiation. For Bracknell and Edinburgh historic data and UKCP09 data 2080 High Emission data set show a drastic decrease, respectively from 0.37 to 0.13 and from 0.33 to 0.14. Diffuse fraction may be used as an indicator of the prevailing sky clarity. If the predictions come true a drastic decrease in the diffuse fraction of this magnitude signifies a radical shift in the character of solar climate for the future. The current solar climate of Bracknell is known for its above average turbidity, the latter stemming from the following factors: inland location, high-density housing, proximity to Heathrow airport and M25 London orbital motorway. Whether such an extreme shift in the sky clarity will occur within a matter of 60--70 years is open to discussion. Practical applications: To adapt effectively against the challenge posed by climate change engineers need to know the extent to which the basic climate variables such as temperature and solar radiation will change. This work has used basic data from the UKCP09 project to analyse the extent of the above change with respect to the basic and other derived data. It was shown that for Scottish and English locations a temperature rise of up to 4--5°C may occur between the present age and the year 2080 for High Emission scenario. It was also shown that the corresponding irradiation strength may increase around 22%. Furthermore, it was also found that if these predictions come true then a drastic decrease in the diffuse fraction of irradiation will produce a radical shift in the character of solar climate. The resulting higher proportion of beam irradiation will have to be handled with care in design of overhangs and other shading contraptions to prevent an excessive increase in cooling load of buildings.

  • An examination of UKCIP02 and UKCP09 solar radiation data sets for the UK climate related to their use in building design
    Building Services Engineering Research and Technology, 2010
    Co-Authors: Yieng Wei Tham, Tariq Muneer, Geoff Levermore, David Chow
    Abstract:

    the UKCP09 grid containing Bracknell the 2080 High Emission scenario data gives an average value of 1002 Wh/m 2 , an increase of 23%. The same trend occurs for Edinburgh, (a present value of 789 Wh/m 2 and the predicted value of 948 Wh/m 2 , an increase of 20%). Note that compounded with presently found increase of 4–58C increase for the above locations, the substantial increase in irradiation will have a much more pronounced increase in the cooling load of buildings. An evaluation of the change in the character of solar radiation was also undertaken. This was done by noting the change in the diffuse fraction of global irradiation. For Bracknell and Edinburgh historic data and UKCP09 data 2080 High Emission data set show a drastic

Ferranti S. L. Wong - One of the best experts on this subject based on the ideXlab platform.

  • Effect of beverages on viscoelastic properties of resin-based dental composites
    Materials, 2015
    Co-Authors: Muhammad Kaleem, Abdul Samad Khan, Ihtesham Ur Rehman, Ferranti S. L. Wong
    Abstract:

    The viscoelastic properties of three commercially available resin-based composites (Filtek™ P60, Filtek™ Supreme, and Filtek™ Z250; 3M ESPE, Bracknell, UK) were measured to determine the effect of beverages on their storage moduli and damping ratios. Rectangular samples of the three hybrid composites were immersed in three beverages at 37 °C for 1, 7, 30, and 60 days. At each time interval, these samples were subjected to three-point bend tests in temperature mode using a Perkin Elmer DMA7 Dynamic Mechanical Analyzer (Perkin Elmer Corp., Waltham, MA, USA) to measure the storage modulus and damping ratio. The immersion time had significant influence on the viscoelastic property of composites and it was found that generally for all samples the storage modulus was reduced, whereas damping values increased with immersion time. The viscoelastic behavior of tested materials seems to be related to the pH environment, hydrophilicity and the chemical composition of composites.

Muhammad Kaleem - One of the best experts on this subject based on the ideXlab platform.

  • Effect of beverages on viscoelastic properties of resin-based dental composites
    Materials, 2015
    Co-Authors: Muhammad Kaleem, Abdul Samad Khan, Ihtesham Ur Rehman, Ferranti S. L. Wong
    Abstract:

    The viscoelastic properties of three commercially available resin-based composites (Filtek™ P60, Filtek™ Supreme, and Filtek™ Z250; 3M ESPE, Bracknell, UK) were measured to determine the effect of beverages on their storage moduli and damping ratios. Rectangular samples of the three hybrid composites were immersed in three beverages at 37 °C for 1, 7, 30, and 60 days. At each time interval, these samples were subjected to three-point bend tests in temperature mode using a Perkin Elmer DMA7 Dynamic Mechanical Analyzer (Perkin Elmer Corp., Waltham, MA, USA) to measure the storage modulus and damping ratio. The immersion time had significant influence on the viscoelastic property of composites and it was found that generally for all samples the storage modulus was reduced, whereas damping values increased with immersion time. The viscoelastic behavior of tested materials seems to be related to the pH environment, hydrophilicity and the chemical composition of composites.

Simon R. Leather - One of the best experts on this subject based on the ideXlab platform.

  • Urban biodiversity: comparison of insect assemblages on native and non-native trees
    Urban Ecosystems, 2012
    Co-Authors: Alvin J. Helden, Gemma C. Stamp, Simon R. Leather
    Abstract:

    Trees are thought to be important for supporting urban biodiversity. However tree species differ considerably in the numbers of invertebrates they support, with potential consequences for higher trophic groups such as birds. In this study the influence of native and non-native trees on the abundance of insects (Hemiptera) and the incidence of insectivorous birds (Paridae) were investigated in the southern English town of Bracknell. The number and species of tree were recorded from each of 17 roundabout and parkland sites. Tree beating was used to sample arboreal Hemiptera and Paridae were recorded either with point counts and transect walks, depending on the size of the site. Due to the great variation between tree species, there was no overall significant difference in species richness or abundance of Hemiptera between native and non-native tree species. However, individual native trees had more species and individuals than non-natives. The proportion of native trees at Bracknell sites was positively related to the abundance of both Hemiptera and the number of Paridae observed. The consequences of vegetation type for insect abundance indicates that in order to sustain and enhance urban biodiversity, careful consideration needs to be given to species of trees present in urban areas.