The aim of the study is to evaluate both environmental damage and saving benefit in selecting building shading devices.The environmental damage from the produc-tion and construction(P&C)of shading devices is evalu...The aim of the study is to evaluate both environmental damage and saving benefit in selecting building shading devices.The environmental damage from the produc-tion and construction(P&C)of shading devices is evaluated.The saving benefit,i.e.,decreasing building operation energy(OE),due to installing shading devices is evaluated.A simple office building module is used.The external shading devices are constructed from concrete-based external shading devices and aluminum-based light shelf devices.Energy design via Life Cycle Energy Assessment(LCEA)and environmental design via Life Cycle Assessments(LCA)are applied.Environmen-tal design is performed when PV energy generation is used.It was found that in energy design,40%of building OE saving benefit is required to compensate energy needed for the P&C of shading devices.In environmental design,100%of the building OE saving benefit is required to compensate for environmental damage stemming from the P&C of shading devices.It was concluded that in energy design,in addition to OE,P&C energy should be evaluated.In environmental design,due to a major reduction in the OE saving benefit,the importance of the P&C environmental damage increased.Environmental design cannot be replaced with energy design when PV energy generation is assumed for building OE needs.展开更多
To investigate effective means of improving the efficiency of organic light-emitting devices （OLEDs） by making full use of ,triplet emission, a phosphorescent material Pt （II） Octaethylporphine （PtOEP） is doped ...To investigate effective means of improving the efficiency of organic light-emitting devices （OLEDs） by making full use of ,triplet emission, a phosphorescent material Pt （II） Octaethylporphine （PtOEP） is doped into polymer host polyspirobifluorene （Spiro） to allow radiative recombination of triplet excitons. The current and brightness characteristics of the devices are tested and the electroluminescent spectra are described. Both fluorescence and phosphorescence are ob- served,and an obvious increase in external quantum efficiency is realized compared to undoped devices when different phosphorescent dopant concentrations are tried. Thus,the phosphorescent emission from triplet excited states might be an effective way to increase the efficiency of OLEDs when the concentration of the phosphorescent dopant is properiy controlled.展开更多
This study examines the daylight and energy performance of 27 external shading scenarios in a high-rise residential building in the urban tropics.The cooling energy,daytime lighting energy and the spatial daylight aut...This study examines the daylight and energy performance of 27 external shading scenarios in a high-rise residential building in the urban tropics.The cooling energy,daytime lighting energy and the spatial daylight autonomy(sDA)of the building model were simulated in Rhino3D and Grasshopper simulation software.The best per-formance scenario(vertical and horizontal shading on the twentieth floor,horizontal shading only for the eleventh floor and no shading for the second floor)satisfied 75 sDA(300lx|50)with corresponding annual enery performance of 16%-20%in the cardinal directions.The baseline scenario,which is the current practice of providing balconies on all floors,reduced daylight to less than 75 sDA on the eleventh and second floor,even though it had higher annual enery performance(19%-24%)than the best performance scenario.Application of the design principles to a case study indicated that 58%of the spaces had over 75 sDA for both Baseline and Best per-formance scenarios,while an increase in enery performance of 1%-3%was found in the Best performance scenario compared to the Baseline.展开更多
文摘The aim of the study is to evaluate both environmental damage and saving benefit in selecting building shading devices.The environmental damage from the produc-tion and construction(P&C)of shading devices is evaluated.The saving benefit,i.e.,decreasing building operation energy(OE),due to installing shading devices is evaluated.A simple office building module is used.The external shading devices are constructed from concrete-based external shading devices and aluminum-based light shelf devices.Energy design via Life Cycle Energy Assessment(LCEA)and environmental design via Life Cycle Assessments(LCA)are applied.Environmen-tal design is performed when PV energy generation is used.It was found that in energy design,40%of building OE saving benefit is required to compensate energy needed for the P&C of shading devices.In environmental design,100%of the building OE saving benefit is required to compensate for environmental damage stemming from the P&C of shading devices.It was concluded that in energy design,in addition to OE,P&C energy should be evaluated.In environmental design,due to a major reduction in the OE saving benefit,the importance of the P&C environmental damage increased.Environmental design cannot be replaced with energy design when PV energy generation is assumed for building OE needs.
文摘To investigate effective means of improving the efficiency of organic light-emitting devices （OLEDs） by making full use of ,triplet emission, a phosphorescent material Pt （II） Octaethylporphine （PtOEP） is doped into polymer host polyspirobifluorene （Spiro） to allow radiative recombination of triplet excitons. The current and brightness characteristics of the devices are tested and the electroluminescent spectra are described. Both fluorescence and phosphorescence are ob- served,and an obvious increase in external quantum efficiency is realized compared to undoped devices when different phosphorescent dopant concentrations are tried. Thus,the phosphorescent emission from triplet excited states might be an effective way to increase the efficiency of OLEDs when the concentration of the phosphorescent dopant is properiy controlled.
文摘This study examines the daylight and energy performance of 27 external shading scenarios in a high-rise residential building in the urban tropics.The cooling energy,daytime lighting energy and the spatial daylight autonomy(sDA)of the building model were simulated in Rhino3D and Grasshopper simulation software.The best per-formance scenario(vertical and horizontal shading on the twentieth floor,horizontal shading only for the eleventh floor and no shading for the second floor)satisfied 75 sDA(300lx|50)with corresponding annual enery performance of 16%-20%in the cardinal directions.The baseline scenario,which is the current practice of providing balconies on all floors,reduced daylight to less than 75 sDA on the eleventh and second floor,even though it had higher annual enery performance(19%-24%)than the best performance scenario.Application of the design principles to a case study indicated that 58%of the spaces had over 75 sDA for both Baseline and Best per-formance scenarios,while an increase in enery performance of 1%-3%was found in the Best performance scenario compared to the Baseline.
