Simulation of Near-field Dispersion of Pollutants Using Detached-Eddy Simulation

A numerical simulation is developed using the unsteady-state turbulence model on a structured highly refined grid to predict the wind-flow field and dispersion field of a pollutant emitted from a rooftop stack around a two-building configuration. The results obtained are compared with those of a steady-state model previously reported by the authors. The pollutant concentrations are examined on the roof where the stack is located as well as on the leeward wall of an upstream tower to the emitting building in order to evaluate how the pollutant is dispersed by the DES model compared to RNG model. DES results are discussed against those from RNG k–ε approach and wind tunnel. The study emphasises limits in reproducing correctly the wind flow and dispersion fields due to underestimation and/or overestimation of the Reynolds stress components and the steady-state methodology when using the RNG k–ε model. Despite such limits, the RNG model produces a similar average error, in terms of concentrations, to that obtained with the DES model

Effect of Stack Height and Exhaust Velocity on Pollutant Dispersion in the Wake of a Building

The dispersion of pollutants exhausted from a building roof stack located in the wake of a tower is investigated by means of the realizable k–ɛ turbulence model. Variations in stack height and pollutant exhaust velocity are considered to assess their influence on the distribution of pollutant concentrations in the neighbourhood of the emitting building. In order to determine optimum locations for fresh-air intakes, the worst case is considered, namely when the wind originates directly upstream of the tower and places the emitting building in its wake. Special attention is given to the evolution of the plume and distribution of pollutant concentrations on the roof and windward wall of the emitting building, as well as on the leeward wall of the upwind tower. Simulation results are compared to wind tunnel experiments conducted in a boundary layer wind tunnel. For this particular configuration, the paper shows that increasing the stack height has an effect similar to that obtained by increasing the momentum ratio, but with some differences, depending upon which wall of the two buildings is considered. On the emitting building, the leeward wall has the lowest concentration values for all stack heights and momentum ratios considered; thus this is the best location for fresh-air intakes. However, for the tower, fresh-air intakes should not be located on the leeward wall due to high pollutant concentrations. The results show completely different pollutant dispersion patterns from those for an isolated building. This highlights the importance of accounting for structures that lie in close proximity to the emitting building

Numerical Simulation of Pollutant Dispersion around Building Complex. Building and Environment

The dispersion of exhausted pollutants from a building roof stack situated in the wake of a neighbouring tower has been studied using computational fluid dynamics (CFD) with the realizable k–ɛ turbulence model for closure. Two scales are considered in this work, full-scale (1:1) and wind tunnel scale (1:200). Of primary interest are the distributions of the plume and of the pollutant concentrations on the building roof as well as on the leeward wall of the tower. Two stack heights and pollutant exhaust velocities have been considered for the distribution of pollutant concentrations in the neighbourhood of the building from which the pollutant is emitted. Results are compared with measurements from field and wind tunnel experiments to estimate the accuracy of simulations

Real-time phase-shift detection of the surface plasmon resonance

We investigate a method to directly measure the phase of a laser beam reflected from a metallic film after excitation of surface plasmon polaritons. This method permits real time access to the phase information, it increases the possible speed of data acquisition, and it may thus prove useful for increasing the sensitivity of surface plasmon based sensors

Inter-laboratory proficiency testing scheme for tumour next-generation sequencing in Ontario: A pilot study

Background A pilot inter-laboratory proficiency scheme for 5 Ontario clinical laboratories testing tumour samples for the Ontario-wide Cancer Targeted Nucleic Acid Evaluation (OCTANE) study was undertaken to assess proficiency in the identification and reporting of next-generation sequencing (NGS) test results in solid tumour testing from archival formalin-fixed, paraffin-embedded (FFPE) tissue. Methods One laboratory served as the reference centre and provided samples to 4 participating laboratories. An analyte-based approach was applied: each participating laboratory received 10 FFPE tissue specimens profiled at the reference centre, with tumour site and histology provided. Laboratories performed testing per their standard NGS tumour test protocols. Items returned for assessment included genes and variants that would be typically reported in routine clinical testing and variant call format (VCF) files to allow for assessment of NGS technical quality. Results Two main aspects were assessed: Technical quality and accuracy of identification of exonic variants Site-specific reporting practices Technical assessment included evaluation of exonic variant identification, quality assessment of the VCF files to evaluate base calling, variant allele frequency, and depth of coverage for all exonic variants. Concordance at 100% was observed from all sites in the technical identification of 98 exonic variants across the 10 cases. Variability between laboratories in the choice of variants considered clinically reportable was significant. Of the 38 variants reported as clinically relevant by at least 1 site, only 3 variants were concordantly reported by all participating centres as clinically relevant. Conclusions Although excellent technical concordance for NGS tumour profiling was observed across participating institutions, differences in the reporting of clinically relevant variants were observed, highlighting reporting as a gap where consensus on the part of Ontario laboratories is needed

Perceptions of the Impact of Positive Action in EU and non-EU Countries

yesAbstract: Around the world, inequalities exist around boundaries of race, social class, gender, disability, religious beliefs and sexual orientation, often resulting from past and current discriminatory practices. Governments have taken certain measures, including enacting policies such as positive action, to remedy such discrimination. This paper provides a comparative analysis of perceptions of the impact of positive action in seven EU and three non-EU countries. The study adopted participatory methods including consensus workshops, interviews and policy analysis to obtain data from designers of positive action. Findings are discussed, conclusions drawn and wide-ranging recommendations are made at the EC, individual countries and organisational levels

Methodological Challenges of Researching Positive Action Measures

This paper highlights some ofthe methodological challenges which have arisen in collecting data for an international study on positive action measures. It will describe strategies employed to encourage participation in the study from as wide a range of organisations and individuals using a mixed method approach. The paper will also discuss the methodological and sensitive issues related to this type of research in organisations and strategies adopted by the research team to ameliorate any problems that have arisen whilst maintaining trustworthiness and rigour in the study

Positive Action Measures Across Different Equality Grounds, Organisations and Sectors in European and Non-european Countries

yesAbstract: This article is based on a large-scale European Commission project on international perspectives on positive action measures. The paper presents an analysis of the perceptions of positive action held by respondents from all the countries participating in an international survey, focussing specifically upon differences across equality grounds, sector and organisation type. This paper will also provide examples of positive action being applied in European and non-European countries that participated in the study. The study adopted extensive literate and online survey to obtain data from designers of positive action. Findings are discussed, conclusions drawn and wide-ranging recommendations are made at the European Commission, individual countries and organisational levels