Journal of Daylighting Maximizing the Performance of Laser Cut Panel by Interaction of Ceiling Geometries and Different Aspect Ratio

Abstract The interaction between different ceiling geometries with laser cut panels (LCPs) is investigated using real experiments and computer simulations to maximize the daylight performance of the LCP. In addition, LCP with different aspect ratios (width to depth ratio) is studied using simulation with clear sky conditions in hot climate region. Two main performance parameters are investigated: illuminance level and distribution uniformity in a large space located in a sub-tropical climate region like Jordan. It was found that curved and chamfered ceilings increased the daylight level in the rear part of the studied room by 20% compared to a horizontal flat ceiling and reduce it by 30% in front part that improve the quality of daylight by improving the uniformity. LCP with high aspect ratio of 5:6 performed well in climate with clear sky and high solar angles than LCP with ratio of 4:6

Maximizing the Performance of Laser Cut Panel by Interaction of Ceiling Geometries and Different Aspect Ratio

The interaction between different ceiling geometries with laser cut panels (LCPs) is investigated using real experiments and computer simulations to maximize the daylight performance of the LCP. In addition, LCP with different aspect ratios (width to depth ratio) is studied using simulation with clear sky conditions in hot climate region. Two main performance parameters are investigated: illuminance level and distribution uniformity in a large space located in a sub-tropical climate region like Jordan. It was found that curved and chamfered ceilings increased the daylight level in the rear part of the studied room by 20% compared to a horizontal flat ceiling and reduce it by 30% in front part that improve the quality of daylight by improving the uniformity. LCP with high aspect ratio of 5:6 performed well in climate with clear sky and high solar angles than LCP with ratio of 4:6

Energy-Efficient Solutions Depending on Building Forms Design with Tilted South and North Facades

Interactions between buildings and outdoor environment variables, such as the sun, wind and precipitation, depend on building parameters such as orientation, colours, materials and forms. Building forms are one of the most important parameters that directly impact the cooling and heating load energy consumption, daylight environment and urban sustainability. The current study focused on how building forms affect the energy performance of buildings. Inclined forms that were shaped based on the inclination of south and north facades were studied. Many methods were used to explore the impacts of several variables, including exposure to direct sunrays and heating and cooling load. Thermal performance and energy consumption were investigated for many inward- and outward-tilted angles forms for both the south and north directions and compared to vertical facades. In addition, the study developed new building forms based on a combination of south and north tilted forms, which have low energy consumption. The configurations achieved an acceptable balance between cooling and heating energy consumption. A series of computer simulations were developed using energy plus a calculation engine within DesignBuilder, SunCast, Radiance and IES VE. The results showed that outward-tilted facades for the south orientation perform well, as they reduced the cooling load due to self-shading. Building forms that balanced south and north tilted facades saved the most energy. South-tilted facades forming only 30° angles performed the best, with average energy savings of 20%. Meanwhile, forms with 30° south-tilted facade and 10° tilted north facades, such as forms 3–6, reduced energy consumption by more than 23% compared to the base case

Optimizing Shading and Thermal Performances of Vertical Green Wall on Buildings in a Hot Arid Region

Due to global concerns about energy issues, global warming, and urban quality, vertical greening systems (VGS) are receiving more attention in construction and design research. Therefore, VGS has become part of building envelope design as a passive technique for saving energy in building sectors. The current study aimed to investigate shading and energy performances of VGS in buildings in hot climate regions and to optimize VGS design as a building design element. The study was conducted through simulation and field experiments in a student housing building at a university campus (Irbid, Jordan). Field measurements were taken to assess the thermal effect of the green wall and daylight performance as well as the efficiency of the typical green wall design configuration. Furthermore, a methodology for accurately representing green walls was established and used. Both simulation and experimentation demonstrated that the thickness of the air cavity and the percentage of foliage coverage can have a substantial impact on the performance of the green wall system. Results showed that green wall systems are effective natural sunscreens and shading systems. A green wall helped to reduce the exterior wall surface temperatures by a range of 6 to 11 °C compared to the base case of the wall without a VGS on different days. In addition, it decreased the interior surface temperature of the investigated southern façade by an average of 5 °C compared to the base case. Green wall design configurations for hot climate regions, such as Jordan, will help designers to use the VGS as a design element. Our findings indicate that GW could help to improve the thermal and daylight environment and thus the results could be taken as indicative for GW wall design in other areas or buildings

Optimizing Shading and Thermal Performances of Vertical Green Wall on Buildings in a Hot Arid Region

Due to global concerns about energy issues, global warming, and urban quality, vertical greening systems (VGS) are receiving more attention in construction and design research. Therefore, VGS has become part of building envelope design as a passive technique for saving energy in building sectors. The current study aimed to investigate shading and energy performances of VGS in buildings in hot climate regions and to optimize VGS design as a building design element. The study was conducted through simulation and field experiments in a student housing building at a university campus (Irbid, Jordan). Field measurements were taken to assess the thermal effect of the green wall and daylight performance as well as the efficiency of the typical green wall design configuration. Furthermore, a methodology for accurately representing green walls was established and used. Both simulation and experimentation demonstrated that the thickness of the air cavity and the percentage of foliage coverage can have a substantial impact on the performance of the green wall system. Results showed that green wall systems are effective natural sunscreens and shading systems. A green wall helped to reduce the exterior wall surface temperatures by a range of 6 to 11 °C compared to the base case of the wall without a VGS on different days. In addition, it decreased the interior surface temperature of the investigated southern façade by an average of 5 °C compared to the base case. Green wall design configurations for hot climate regions, such as Jordan, will help designers to use the VGS as a design element. Our findings indicate that GW could help to improve the thermal and daylight environment and thus the results could be taken as indicative for GW wall design in other areas or buildings

Singlet molecular oxygen regulates vascular tone and blood pressure in inflammation

Singlet molecular oxygen (O-1(2)) has well-established roles in photosynthetic plants, bacteria and fungi(1-3), but not in mammals. Chemically generated O-1(2) oxidizes the amino acid tryptophan to precursors of a key metabolite called N-formylkynurenine(4), whereas enzymatic oxidation of tryptophan to N-formylkynurenine is catalysed by a family of dioxygenases, including indoleamine 2,3-dioxygenase 1(5). Under inflammatory conditions, this haem-containing enzyme is expressed in arterial endothelial cells, where it contributes to the regulation of blood pressure(6). However, whether indoleamine 2,3-dioxygenase 1 forms O-1(2) and whether this contributes to blood pressure control have remained unknown. Here we show that arterial indoleamine 2,3-dioxygenase 1 regulates blood pressure via formation of O-1(2). We observed that in the presence of hydrogen peroxide, the enzyme generates O-1(2) and that this is associated with the stereoselective oxidation of L-tryptophan to a tricyclic hydroperoxide via a previously unrecognized oxidative activation of the dioxygenase activity. The tryptophan-derived hydroperoxide acts in vivo as a signalling molecule, inducing arterial relaxation and decreasing blood pressure; this activity is dependent on Cys42 of protein kinase G1 alpha. Our findings demonstrate a pathophysiological role for O-1(2) in mammals through formation of an amino acid-derived hydroperoxide that regulates vascular tone and blood pressure under inflammatory conditions