Simulation of Imagined Realities: Environmental Design Decision Support Tools in Architecture

The spur for this research was a lack of use by architecture practitioners of the environmental design decision support tools (eddst’s) they learn to use during their education. It was hypothesised that lessons for the improvement of eddst’s could be found in a systematic examination of the problems encountered by design teams with a range of currently available eddst’s. The research plan was to establish through surveys and case studies how practising architects who have tried to use building eddst’s assess the effectiveness of these tools. A range of different types of eddst was examined, each addressing a different aspect of the environment in buildings. The research did not achieve its original goal of developing a formula for the generation of new eddst’s for architects in the fields of building acoustics, lighting, thermal design and aerodynamics. What was found is a more fundamental common denominator underlying building design eddst’s: the need for built-in Quality Assurance measures that assure not only the architect, but also the simulationist and the client of the reality of the ebuilding performance predictions. It was found that contrary to their general reputation, designers do want detailed quantitative environmental information. They want to be able to discuss costs and benefits of decisions. However, they also want to be able to understand and trust this information. The output from eddst’s must therefore also be qualitative in the sense that it communicates the quality of life resulting from a design decision. What is proposed therefore for designers and simulationists is Quality Assurance (QA) procedures that are codified and incorporated into the design tools themselves. These are to ensure that the ‘black box’ of a digital simulation of building performance yields information that designers feel they can trust. The research demonstrates that to address the issues identified in the practitioner surveys, a Quality Control (QC) reality test is the single most important feature needed in any QA process. This would be a reality test that examines whether the ebuildings constructed with an eddst behave in a believable manner - like a ‘real’ building. The proposed Simulation QA (SimQA) approach is an internet web service. It is a database of the databases available on the internet of Quality Assured performance data. Each time a person sets up a new Quality tested eddst input file or measures a building, it becomes another “data point” - another database listed in the SimQA metadata. Also required in a robust QA process is the development of international norms for the simulation of building performance. www.aecsimqa.net is proposed as the venue for the development of an international documentation standard for simulation. Finally, modern computer-based building performance simulation has not rid the design profession of its traditional problem with design tools: that they evaluate completed designs. The proposed database will make web-accessible a set of tested building designs and their associated performance measures. Placed at the designer’s fingertips this will reveal insights into how their current building design should perform. It should be possible to generate initial design ideas based on systematic study of the successful precedents

Evaluation of extractants for estimation of the phytoavailable trace metals in soils

Despite its environmental (and financial) importance, there is no agreement in the literature as to which extractant most accurately estimates the phytoavailability of trace metals in soils. A large dataset was taken from the literature, and the effectiveness of various extractants to predict the phytoavailability of Cd, Zn, Ni, Cu, and Pb examined across a range of soil types and contamination levels. The data suggest that generally, the total soil trace metal content, and trace metal concentrations determined by complexing agents (such as the widely used DTPA and EDTA extractants) or acid extractants (such as 0.1 M HCl and the Mehlich 1 extractant) are only poorly correlated to plant phytoavailability. Whilst there is no consensus, it would appear that neutral salt extractants (such as 0.01 M CaCl2 and 0.1 M NaNO3) provide the most useful indication of metal phytoavailability across a range of metals of interest, although further research is required

Radiation imaging apparatus

A radiation imaging system using a charge multiplier and a position sensitive anode in the form of periodically arranged sets of interconnected anode regions for detecting the position of the centroid of a charge cloud arriving thereat from the charge multiplier. Various forms of improved position sensitive anodes having single plane electrode connections are disclosed. Various analog and digital signal processing systems are disclosed, including systems which use the fast response of microchannel plates, anodes and preamps to perform scintillation pulse height analysis digitally

Solar potential in extreme climate conditions: comparative analysis of two district case studies in Norway and Reunion Island

International audienceThis work aims to investigate the application and replicability of parametric solar design to both existing and future development urban areas in two extreme climate conditions: Øvre Rotvoll in Norway (subarctic climate) and Ravine Blanche in Reunion Island (tropical humid climate). The interplay between urban morphology and its potential for passive and active solar energy strategies has been investigated. The methodology combines the parametric modelling software Rhinoceros-Grasshopper, with two Radiance-based solar simulation tools to optimise the solar potential of a district. The application of a new workflow is studied over the computation of various design scenarios in an existing urban environment at both the district and the building scale. The results show differences and similarities between climate-specific interventions that can be used as supportive instruments for the ongoing local planning processes. The study demonstrates how parametric optimisation allows maximising the solar potential of urban areas at different latitudes despite climatic and urban densification constraints

Thermal and visual comfort assessment of natural ventilated office buildings in Europe and North America

Natural ventilation has the potential to significantly improve indoor comfort conditions and provide good indoor air quality by increasing both the indoor air velocity and the rate of air changes inside the building. However, the performance of this technique strongly depends on various parameters, such as climate, urban form and building characteristics (geometrical and thermal). With the aim of showing how natural ventilation can be successfully applied to existing office buildings in many different urban climates, an extensive parametric study has been carried out that takes into account the factors most likely to be relevant. Firstly, a characterization of different climates and the cities representative of them has been developed. Then, representative office buildings for each city have been modelled both in their base configurations and when natural ventilation is employed, in representative urban configurations. This task has been accomplished by coupling three different simulation tools in an integrated approach. CFD, thermal and daylighting simulations allowed exploration of which are the most relevant parameters that affect thermal comfort and have some implications on visual comfort as well. The large number of models simulated (almost 13 thousand) also provided the team with the opportunity to develop a new methodology for finding the best performing thermal models, based on Givoni’s thermal comfort theory rather than monthly or annual energy needs

Phosphorus sorption characteristics and interactions with leaf litter‑derived dissolved organic matter leachate in iron‑rich sediments of a sub‑tropical ephemeral stream

This study investigated the infuence of dissolved organic matter (DOM) additions on phosphate sorption kinetics of iron-rich sediments (39–50% hematite and goethite) from an ephemeral stream in the arid Pilbara region of sub-tropical northwest Australia. While phosphate sorption in stream sediments is known to be strongly infuenced by sediment mineralogy as well as interactions with DOM, the mechanisms and signifcance of DOM on P-release from sediments with high sorption capacities, are largely undescribed. We assessed phosphorus (P) sorption behaviours by adding a range of solutions of known inorganic P concentrations that were amended with variable loadings of DOM derived from leachates of leaf litter to sediments from stream pools during the non-fowing phase. We compared the sorption capacity of the sediments and concurrent changes in DOM composition measured using fuorescence spectroscopy. We show that the low-dose DOM addition (~ 4 mg L−1 DOC) had the efect of reducing sediment P adsorption capacity, while for the high-dose DOM addition (~ 45 mg L−1 DOC), it was increased. The high-dose DOM was similar to pore water DOC and likely saturated sediment surface adsorption sites and produced P–OM–Fe complexes. This resulted in increased removal of P from solution. Sediment P sorption characteristics were well ftted to both Freundlich and Langmuir isotherm models regardless of DOC concentration. Langmuir P sorption maxima ranged from 0.106 to 0.152 mg g−1. General P sorption characteristics of these iron-rich sediments did not difer among pools of contrasting hydrological connectivity. Our results show how humic-rich DOM can modulate the sediment P availability in dryland streams. Unravelling the complexities of P availability is of particular significance to further our understanding of biogeochemical processes in aquatic ecosystems where P often acts as a limiting nutrient

Energy use and height in office buildings

The relationship between energy use and height is examined for a sample of 611 office buildings in England and Wales using actual annual metered consumption of electricity and fossil fuels. The buildings are of different ages; they have different construction characteristics and methods of heating and ventilation; and they include both public and commercial offices. When rising from five storeys and below to 21 storeys and above, the mean intensity of electricity and fossil fuel use increases by 137% and 42% respectively, and mean carbon emissions are more than doubled. A multivariate regression model is used to interpret the contributions of building characteristics and other factors to this result. Air-conditioning is important, but a trend of increased energy use with height is also found in naturally ventilated buildings. Newer buildings are not in general more efficient: the intensity of electricity use is greater in offices built in recent decades, without a compensating decrease in fossil fuel use. The evidence suggests it is likely – although not proven – that much of the increase in energy use with height is due to the greater exposure of taller buildings to lower temperatures, stronger winds and more solar gains

Brief Note A Radiocarbon-Dated Mammoth Site, Marion County, Ohio

Author Institution: Ohio Division of Geological Survey; Ohio Historical Society; Ohio State University-Mario