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Alan Robins

Bio: Alan Robins is an academic researcher from University of Surrey. The author has contributed to research in topics: Wind tunnel & Atmospheric dispersion modeling. The author has an hindex of 37, co-authored 111 publications receiving 3258 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, a review of the existing knowledge of nanoparticles in the urban atmosphere, highlights recent advances in our understanding and discusses research priorities and emerging aspects of the subject, as well as the role of removal mechanisms of various kinds.

307 citations

Journal ArticleDOI
TL;DR: The UK atmospheric dispersion modelling system is a computer code for modelling the dispersion of buoyant or neutrally buoyant gaseous and particulate emissions to the atmosphere.

234 citations

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TL;DR: In this paper, the surface shear stress of uniform urban-type surfaces of two different area densities were performed in a wind tunnel, together with direct measurements of the surface drag, and the aerodynamic characteristics of each surface were determined and compared.

161 citations

Journal ArticleDOI
TL;DR: The background of the DAPPLE project, the study design and methodology for data collection, some preliminary results from the first field campaign in central London, the future for this work and the future of the street canyon intersection are introduced.

120 citations

Journal ArticleDOI
TL;DR: In this article, a wind tunnel study has been undertaken to assess the influence of solar-induced wall heating on the airflow pattern within a street canyon under low-speed windconditions.
Abstract: A wind tunnel study has been undertaken to assess theinfluence of solar-induced wall heating on the airflowpattern within a street canyon under low-speed windconditions. This flow is normally dominated by large-scalevortical motion, such that the wind moves downwards at thedownstream wall. In the present work the aim has been toexamine whether the buoyancy forces generated at this wallby solar-induced heating are of sufficient strength tooppose the downward inertial forces and, thereby, changethe canyon flow pattern. Such changes will also influencethe dispersion of pollutants within the street. In theexperiments the windward-facing wall of a canyon has beenuniformly heated to simulate the effect of solar radiation.Four different test cases, representing different degreesof buoyancy (defined by a test Froude number, Fr), havebeen examined using a simple, 2-D, square-section canyonmodel in a wind tunnel. For reference purposes, the neutralcase (no wall heating), has also been studied. The approachflow boundary layer conditions have been well defined, withthe wind normal to the main canyon axis, and measurementshave been taken of canyon wall and air temperatures andprofiles of mean velocities and turbulence intensities.Analysis of the results shows clear differences in the flowpatterns. As Fr decreases from the neutral case there arereductions of up to 50% in the magnitudes of the reverseflow velocities near the ground and in the upward motionnear the upstream wall. A marked transition occurs at Fr ≈ 1, where the single dominant vortex, existing at higher Fr values, weakens and moves upwards whilst a lower region of relatively stagnant flow appears. This transition hadpreviously been observed in numerical model predictions butat a Fr at least an order of magnitude higher.

118 citations


Cited by
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Journal Article
TL;DR: In this article, the authors present a document, redatto, voted and pubblicato by the Ipcc -Comitato intergovernativo sui cambiamenti climatici - illustra la sintesi delle ricerche svolte su questo tema rilevante.
Abstract: Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

4,187 citations

Journal ArticleDOI
TL;DR: It is demonstrated how air pollution data can be analysed quickly and efficiently and in an interactive way, freeing time to consider the problem at hand.
Abstract: openair is an R package primarily developed for the analysis of air pollution measurement data but which is also of more general use in the atmospheric sciences. The package consists of many tools for importing and manipulating data, and undertaking a wide range of analyses to enhance understanding of air pollution data. In this paper we consider the development of the package with the purpose of showing how air pollution data can be analysed in more insightful ways. Examples are provided of importing data from UK air pollution networks, source identification and characterisation using bivariate polar plots, quantitative trend estimates and the use of functions for model evaluation purposes. We demonstrate how air pollution data can be analysed quickly and efficiently and in an interactive way, freeing time to consider the problem at hand. One of the central themes of openair is the use of conditioning plots and analyses, which greatly enhance inference possibilities. Finally, some consideration is given to future developments.

1,303 citations

Journal ArticleDOI
TL;DR: General classes of direct value comparison, coupling real and modelled values, preserving data patterns, indirect metrics based on parameter values, and data transformations are discussed.
Abstract: In order to use environmental models effectively for management and decision-making, it is vital to establish an appropriate level of confidence in their performance. This paper reviews techniques available across various fields for characterising the performance of environmental models with focus on numerical, graphical and qualitative methods. General classes of direct value comparison, coupling real and modelled values, preserving data patterns, indirect metrics based on parameter values, and data transformations are discussed. In practice environmental modelling requires the use and implementation of workflows that combine several methods, tailored to the model purpose and dependent upon the data and information available. A five-step procedure for performance evaluation of models is suggested, with the key elements including: (i) (re)assessment of the model's aim, scale and scope; (ii) characterisation of the data for calibration and testing; (iii) visual and other analysis to detect under- or non-modelled behaviour and to gain an overview of overall performance; (iv) selection of basic performance criteria; and (v) consideration of more advanced methods to handle problems such as systematic divergence between modelled and observed values.

1,207 citations

Journal ArticleDOI
01 Jan 1957-Nature
TL;DR: The Structure of Turbulent Shear Flow by Dr. A.Townsend as mentioned in this paper is a well-known work in the field of fluid dynamics and has been used extensively in many applications.
Abstract: The Structure of Turbulent Shear Flow By Dr. A. A. Townsend. Pp. xii + 315. 8¾ in. × 5½ in. (Cambridge: At the University Press.) 40s.

1,050 citations