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Drafting is distinctive for team pursuit races in long-track speed skating. This study aims to compare the impact of drafting on physical intensity (heart rate [HR]) and perceived intensity (ratings of perceived exertion [RPE]) per drafting position. Eighteen skilled male (n = 9) and female (n = 9) skaters (20.0 ± 4.8 years) skated three trials, in first, second or third position, with consistent average velocity (F2,10 = 2.30, p = 0.15, ηp2 = 0.32). Differences in HR and RPE (Borg CR−10 scale) were compared within-subjects (three positions) using a repeated-measures ANOVA (p < 0.05). Compared to the first position, HR was lower in the second (benefit 3.2%) and third (benefit 4.7%) position and lower in third compared to second position (benefit 1.5%), observed in 10 skaters (F2,28 = 28.9, p < 0.001, ηp2= 0.67). RPE was lower when comparing second (benefit 18.5%) and third (benefit 16.8%) position to first (F1.3,22.1 = 7.02, p < 0.05, ηp2= 0.29) and similar for third and second positions., observed in 8 skaters. Even though the physical intensity was lower when drafting in third versus second position, the perceived intensity was equal. There were large interindividual differences between skaters. Coaches are advised to adopt a multidimensional, tailored approach when selecting and training skaters for a team pursuit. [ABSTRACT FROM AUTHOR]

The article discusses the findings of a large-scale analysis of the association between air pollutants and leucocyte telomere length in the UK Biobank (UKB). Topics covered include the recruitment and phenotyping of UKB participants, the assessment of the correlation coefficients between air pollutants and with socioeconomic status and the limitations of the study.

The undergoing transition from conventional to converter-interfaced renewable generation leads to significant challenges in maintaining frequency stability due to declining system inertia. In this paper, a novel control framework for Synthetic Inertia (SI) provision from Wind Turbines (WTs) is proposed, which eliminates the secondary frequency dip and allows the dynamics of SI from WTs to be analytically integrated into the system frequency dynamics. Furthermore, analytical system frequency constraints with SI provision from WTs are developed and incorporated into a stochastic system scheduling model, which enables the provision of SI from WTs to be dynamically optimized on a system level. Several case studies are carried out on a Great Britain 2030 power system with different penetration levels of wind generation and inclusion of frequency response requirements in order to assess the performance of the proposed model and analyze the influence of the improved SI control scheme on the potential secondary frequency dip. The results demonstrate that the inclusion of SI provision from WTs into Unit Commitment (UC) can drastically impact the overall system costs. [ABSTRACT FROM AUTHOR]

BACKGROUND: The drug delivery characteristics of each inhaler/spacer combination are unique. The spacer size as well as the presence of electrostatic charge greatly influence the inhaler dose emission and in vivo delivery. Using a previously developed urinary pharmacokinetic method, we have measured the relative lung and systemic bioavailability of beclometasone dipropionate (BDP) after inhalation from 2 hydrofluroalkane-beclometasone dipropionate (HFA-BDP) formulations when used with a spacer. METHODS: 12 healthy volunteers received 8 randomized doses, separated by 7 d, of inhaled of BDP with either the Clenil pressurized metered-dose inhaler (pMDI; 250 µg) or the breath-actuated Qvar Easi-Breathe inhaler (100 µg), used alone or with a spacer. The urinary amounts of BDP excreted and retained in the spacer were assayed using a liquid chromatographic mass spectrometer. The spacer was assessed after washing with a detergent solution that was either rinsed or not rinsed with water. In addition, the aerodynamic characterization of each inhaler/spacer combination was assessed using the Andersen Cascade Impactor operated at 28 L/min using a 4-L inhalation volume. The amount of BDP deposited in the induction port, spacer, and various Anderson Cascade Impactor stages were determined. RESULTS: The in vivo 30-min urinary excretion and the in vitro fine particle dose results were only slightly affected by adding the spacer to the Clenil pMDI or the Qvar Easi-Breathe inhaler. However, the spacer significantly reduced drug particle impaction in the oropharynx and minimized deposition in the gastrointestinal tract. Therefore, using spacers with BDP inhalers is associated with a more favorable therapeutic ratio because it has little effect on lung dose, but it significantly reduced throat deposition. An improved lung deposition was achieved with non-rinsed spacers compared to spacers rinsed with water. CONCLUSION: The difference in the BDP particle size between formulations as well as spacer size greatly affected drug deposition in different regions of the respiratory tract. [ABSTRACT FROM AUTHOR]

Vehicle manufacturers are required to reduce their European sales-weighted emissions to 95 g CO 2 /km by 2020, with the aim of reducing on-road fleet fuel consumption. Nevertheless, current fuel consumption models are not suited for the European market and are unable to account for uncertainties when used to forecast passenger vehicle energy-use. Therefore, a new methodology is detailed herein to quantify new car fleet fuel consumption based on vehicle design metrics. The New European Driving Cycle (NEDC) is shown to underestimate on-road fuel consumption in Spark (SI) and Compression Ignition (CI) vehicles by an average of 16% and 13%, respectively. A Bayesian fuel consumption model attributes these discrepancies to differences in rolling, frictional and aerodynamic resistances. Using projected inputs for engine size, vehicle mass, and compression ratio, the likely average 2020 on-road fuel consumption was estimated to be 7.6 L/100 km for SI and 6.4 L/100 km for CI vehicles. These compared to NEDC based estimates of 5.34 L/100 km (SI) and 4.28 L/100 km (CI), both of which exceeded mandatory 2020 fuel equivalent emissions standards by 30.2% and 18.9%, respectively. The results highlight the need for more stringent technological developments for manufacturers to ensure adherence to targets, and the requirements for more accurate measurement techniques that account for discrepancies between standardised and on-road fuel consumption. [ABSTRACT FROM AUTHOR]

Increases in the volume of trade within the UK rail freight industry have led to proposed increases in freight train speeds. There is a concern that the unsteady slipstream created around a moving freight train could have implications on efficiency and the safety of passengers waiting on platforms or trackside workers. This paper describes a series of moving model-scale experiments conducted at the University of Birmingham’s TRAIN rig facility. Experiments were undertaken to assess the slipstream development of a container freight train and draw conclusions on flow characteristics. In this paper the term ‘freight train’ refers to a series of flatbed wagons loaded with ISO standard shipping containers hauled by a Class 66 locomotive. In-depth analysis of slipstream velocity and static pressure ensemble average results at train side and above the roof identified a series of key flow regions. Results within the boundary layer region exhibit an influence from container loading configuration. Slipstream magnitudes are larger than typical high speed passenger train results, which it is suggested is related to the vehicle shape. The effect of train length and train speed was also considered. A detailed analysis of the nature of slipstream velocity components in specific flow regions is investigated, and conclusions drawn on characteristic patterns and factors influencing possible safety issues. The analysis highlighted differences created through decreased container loading efficiencies, creating increased boundary layer growth with a larger displacement thickness with higher turbulence intensities. Integral time and length scales calculated through autocorrelation indicate that proposed limits of human instability are exceeded for the container freight train with a lower loading efficiency. Overall the results from this paper offer for the first time a definitive experimental study on container freight slipstream characteristics, allowing the nature of the flow field around freight trains to be understood in far greater detail than before. [ABSTRACT FROM AUTHOR]

Single particle analysis of an industrially polluted atmosphere in Port Talbot, South Wales, United Kingdom was conducted using Aerosol-Time-of-Flight Mass Spectrometry (ATOFMS). During the four week sampling campaign, a total of 5,162,018 particles were sized in the size range 0.2–1.9 μm aerodynamic diameter. Of these, 580,798 were successfully ionized generating mass spectra. K-means clustering employed for analysing ATOFMS data utilized 96% of the hit particles to generate 20 clusters. Similar clusters were merged together and 17 clusters were generated from which 7 main particle groups were identified. The particle classes include: K-rich particles (K–CN, K–NO 3 , K–EC, K–Cl–PO 3 and K–HSO 4 ), aged sea salt (Na–NO 3 ), silicate dust (Na–HSiO 2 ), sulphate rich particles (K–HSO 4 ), nitrate rich particles (AlO–NO 3 ), Ca particles (Ca–NO 3 ), carbon-rich particles (Mn–OC, Metallic–EC, EC, EC–NO 3 and OC–EC), and aromatic hydrocarbon particles (Arom–CN, Fe–PAH–NO 3 and PAH–CN). With the aid of wind sector plots, the K–Cl–PO 3 and Na–HSiO 2 particle clusters were related to the steelworks blast furnace/sinter plant while Ca-rich particles arose from blast furnace emissions. K–CN, K–EC, Na–HSiO 2 , K–HSO 4 , Mn–OC, Arom–CN, Fe–PAH–NO 3 , and PAH–CN particles were closely linked with emissions from the cokemaking and mills (hot and cold) steelworks sections. The source factors identified by the ATOFMS were compared with those derived from multivariate analysis using Multilinear Engine (ME-2) applied to filter samples analysed off-line. Both methods of source apportionment identified common source factors including those within the steelworks (blast furnace, sinter, cokemaking), as well as marine, traffic and secondary particles, but quantitative attribution of mass is very different. [ABSTRACT FROM AUTHOR]

Abstract: An analytical methodology for predicting above-roof mean wind speeds in urban areas is first used to map wind speeds over four different UK cities. The methodology utilises detailed geometric data describing buildings and vegetation to calculate the aerodynamic characteristics of the urban surfaces, and accounts for the influence of building height heterogeneity and wind direction upon wind profiles. The initial objective of the work is to determine the accuracy of the methodology when using detailed geometric data describing building roof shapes in addition to their heights, to estimate surface aerodynamic parameters. By integrating detailed LiDAR (light detection and ranging) data into the methodology and comparing the predictions with measured data, predictive accuracy is found to improve significantly with respect to previous results obtained using less detailed geometric datasets which describe each building with a single height. Subsequently, a preliminary evaluation of the cumulative, city-scale potential for generating wind energy is made, using the UK City of Leeds as a case study. The results suggest that from the point of view of wind resource, 2000 to 9500 viable building-mounted wind turbine locations may exist in Leeds, highlighting the potential for this technology to be far more widely deployed than has presently been achieved. However, the calculations are shown to be highly sensitive to the viable wind speed selected, which in turn depends on financial support and technological progress. An investigation is then made into where, in general, viable roof-top turbine locations may be found. The results suggest that there are viable sites distributed throughout the city, including within the complex city centre, where at the most suitable locations above-roof wind speeds may be comparable to those observed at well exposed rural sites. However, in residential areas, consisting of groups of buildings of similar heights, it is likely that the majority of properties will be unsuitable turbine locations. The wind maps and methodology described in this paper may be utilised by turbine suppliers and customers for assessing the viability of potential sites, as well as being instructive for policymakers developing subsidies for small-scale renewable energy projects. [Copyright &y& Elsevier]

Detailed three-dimensional building data and a morphometric model are used to estimate the aerodynamic roughness length z and displacement height d over a major UK city (Leeds). Firstly, using an adaptive grid, the city is divided into neighbourhood regions that are each of a relatively consistent geometry throughout. Secondly, for each neighbourhood, a number of geometric parameters are calculated. Finally, these are used as input into a morphometric model that considers the influence of height variability to predict aerodynamic roughness length and displacement height. Predictions are compared with estimations made using standard tables of aerodynamic parameters. The comparison suggests that the accuracy of plan-area-density based tables is likely to be limited, and that height-based tables of aerodynamic parameters may be more accurate for UK cities. The displacement heights in the standard tables are shown to be lower than the current predictions. The importance of geometric details in determining z and d is then explored. Height variability is observed to greatly increase the predicted values. However, building footprint shape only has a significant influence upon the predictions when height variability is not considered. Finally, we develop simple relations to quantify the influence of height variation upon predicted z and d via the standard deviation of building heights. The difference in these predictions compared to the more complex approach highlights the importance of considering the specific shape of the building-height distributions. Collectively, these results suggest that to accurately predict aerodynamic parameters of real urban areas, height variability must be considered in detail, but it may be acceptable to make simple assumptions about building layout and footprint shape. [ABSTRACT FROM AUTHOR]

Recent experience with the operation of high-speed railways in the UK and elsewhere has revealed the phenomenon, termed ‘ballast flight’, of ballast particles becoming airborne during the passage of trains, potentially causing damage to both the railhead and the vehicle. This article reports the results of an investigation into the mechanical and aerodynamic forces acting on ballast particles that are generated during the passage of a high-speed train and addresses the question whether these might offer a possible explanation for the initiation of ballast flight. As the high-speed trains passed, measurements were made of the air pressure and velocity at various locations across the track, and of the velocity and acceleration of the track system (sleeper and rails) and the ballast itself. The aerodynamic forces exerted on a suspended ballast particle were also measured. An analytical model of the behaviour of small ballast particles was constructed to assist in the interpretation of the measured data. Analysis of the data and modelling suggest that neither mechanical forces nor aerodynamic forces in isolation are likely to be sufficient to initiate ballast flight under the conditions investigated, but that the phenomenon could arise from a combination of the two effects. It appears that the process is stochastic in nature: further work, with an increased number of measurements, is required to explore this. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a combined experimental and computational study of the aerodynamics and passive ventilation characteristics of small livestock trailers within which the majority of animals in the United Kingdom are transported to market. Data obtained from a series of wind tunnel experiments using a 1/7th scale model of a simplified towing vehicle and trailer are compared with complementary computational fluid dynamics (CFD) analyses, based on steady-state RANS turbulence modelling, of the coupled external/internal flow field. Good agreement between the two is obtained everywhere except at the rear of the trailer. Since the internal flow field and overall ventilation rates contribute to animal welfare, CFD is used to generate detailed internal flow fields and air residence times for use within an overall welfare assessment. The results demonstrate that the flow fields in the upper and lower decks differ significantly and that ventilation rates are much larger and air residence times much smaller on the upper deck. [Copyright &y& Elsevier]

Abstract: The results of a numerical investigation into the aerodynamic characteristics and aeroelastic stability of a proposed footbridge across a highway in the north of England are presented. The longer than usual span, along with the unusual nature of the pedestrian barriers, indicated that the deck configuration was likely to be beyond the reliable limits of the British design code BD 49/01. The calculations were performed using the discrete vortex method, DIVEX, developed at the Universities of Glasgow and Strathclyde. DIVEX has been successfully validated on a wide range of problems, including the aeroelastic response of bridge deck sections. In particular, the investigation focussed on the effects of non-standard pedestrian barriers on the structural integrity of the bridge. The proposed deck configuration incorporated a barrier comprised of angled flat plates, and the bridge was found to be unstable at low wind speeds, with the plates having a strong turning effect on the flow at the leading edge of the deck. These effects are highlighted in both a static and dynamic analysis of the bridge deck, along with modifications to the design that aim to improve the aeroelastic stability of the deck. Proper orthogonal decomposition (POD) was also used to investigate the unsteady pressure field on the upper surface of the static bridge deck. The results of the flutter investigation and the POD analysis highlight the strong influence of the pedestrian barriers on the overall aerodynamic characteristics and aeroelastic stability of the bridge. [Copyright &y& Elsevier]

High-resolution numerical simulations are performed for three nights for each of two areas of the United Kingdom. Area-averaging techniques are then used to calculate effective stability functions for turbulence parametrizations in models using typical mesoscale and global spatial resolutions. Comparisons are made with parametrizations commonly used in numerical weather prediction models. The present results do not suggest that significant enhancement of the stability functions above 50 m is justified. Closer to the surface, more significant enhancement is observed in some regions. It is shown that the amount of enhancement is related to the variability of the orography. [ABSTRACT FROM AUTHOR]

Since the mid 1980s, British Aerospace's Military Aircraft Division has been committed to the concept of real time data monitoring and analy sis in the flight test environment as a prime means of improving effectiveness. This paper presents an overview of the aerodynamic aspects of flight testing, the area which was chosen for the proof of concept phase and was utilized extensively on the experimental aircraft programme. The techniques developed and methods employed are discussed in more detail and examples of the achievements are given. The lessons learnt from the proof of concept phase are reviewed and the implementations of the concept on current major projects are briefly outlined. [ABSTRACT FROM AUTHOR]

The article offers news briefs related to energy resources and aerodynamics in Great Britain. Chief scientific adviser Robert Watson at the Department for Environment, Food and Rural Affairs (Defra) says that the country may have to increase the production usage of rare earth metals as it transfers into a greener economy. Meanwhile, MIRA Ltd. specialists have used full scale wind tunnel to validate the aerodynamic stability of a car nose for the 2011 Red Nose Day to be held on March 18, 2011.

The article profiles John Fitzpatrick, a professor of Mechanical Engineering and the Head of the Engineering School at Trinity College in Dublin, Ireland is presented. He is also a member of the Royal Irish Academy, the CEAS Aeroacoustics Specialists Committee, a fellow of the Royal Academy of Engineering in Great Britain and the Irish Academy of Engineering.

This article reports that the Great Britain based Intelligent Energy has unveiled what is described as the world's first purpose-built fuel cell motorbike. Primarily powered by a lkW hydrogen-fuelled proton exchange membrane (PEM) cell, the bike reaches speeds of 50mph and has a range of 100 miles. The Emissions Neutral Vehicle, or ENV is streamlined and aerodynamic and is almost silent in operation. It has simple controls, with a throttle directly linked to the applied power. Manufactured with hollow-cast aircraft grade aluminum, the bike's total mass including the fuel cell is 180 kg.

Highlights the 2004 Aerospace Aerodynamics Conference. Role of Great Britain in aerodynamics; Collaborative windmill tunnel.