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This paper evaluates a unique, transdisciplinary participatory research and knowledge exchange methodology developed in the Drought Risk and You (DRY) project and offers it as a transferable framework for others engaging stakeholders and systemic connections with environmental risk. Drought in the UK is a complex, diffuse and hidden risk, involving multiple stakeholders and systemic connections across diverse sectors. Historically, drought risk management has been underpinned by specialist science and technology implemented by statutory stakeholders. This paper critically evaluates the social learning from a longitudinal research process that involved co-working with seven river catchment-based, multi-stakeholder groups. The DRY project was a creative experiment in bringing drought science and stories into the same space, aiming to reveal different knowledges—specialist science, practical sector-level insight, and local knowledge—as a new evidence base to support better decision-making in UK drought risk management. An evaluative multi-method research methodology was overlaid on this process, using surveys, within meeting reflective evaluations, and summative semi-structured narrative interviews. This paper reflects on participant experiences of the ‘open’ scientific modelling development, ‘storying’ approaches, and their iterative interaction. It outlines the enablers, inhibitors and required support for this engagement process, which aimed to facilitate integration of different forms of knowledge as evidence, with social and sustainability learning among diverse stakeholders at its core. The process offered opportunity for valuable experiential learning as researchers of the nuanced impacts of intersecting factors on participatory place-based methods. It showed that similar approaches to science-narrative dialogic processes can play out locally to integrate aspects of social and sustainability learning in different ways. This sustainability learning provided a valuable platform for creative multi-stakeholder scenario-ing possible drought futures for increased local climate resilience. It then proposes a transferable research framework that promotes participatory, place-based, narrative-science knowledge exchange for building local capital for managing systemic environmental risk.

Alpha-pinene (AP), produced by pine trees and other plants, is the main component of turpentine and is used as a fragrance and flavor ingredient. Exposure occurs via the use of personal care and household cleaning products and in the lumber industry. Despite widespread exposure, toxicity data for AP are limited. The objective of this work was to develop and validate a method to quantitate AP in rodent blood and mammary glands, in support of toxicokinetic and toxicology studies of AP. The method uses 100 µL of blood or $\sim$100 mg of mammary gland with analysis by headspace (HS) gas chromatography--mass spectrometry. The samples are diluted with internal standard (2H3-AP, IS) and sealed in HS vials; mammary glands are homogenized within the vial. The vials are equilibrated briefly at 60°C before a HS sample is analyzed. The method was validated in Sprague Dawley rat blood over the range 5–500 ng/mL and mammary gland over the range 100–5,000 ng/g. The method was linear (r ≥ 0.99), accurate (mean relative error (RE) ≤ ±13.4%) and precise (relative standard deviation (RSD) ≤ 7.1%) in both matrices. Recoveries incorporating IS were ≥88.7% at all concentrations in both tissues. Standards as high as 1,500 ng/mL in blood and 20,000 ng/g in mammary gland could be analyzed using lower injection volume or extrapolating the calibration curve beyond the upper limit of quantitation (mean %RE ≤ ±18.7; %RSD ≤ 2.2). Loss of AP occurred during overnight autosampler storage as well as frozen storage in as few as 15 days, but incorporation of IS prior to storage corrected for the loss such that calculated concentrations were within 84.7–117% of day 0 concentrations following frozen storage up to ≥32 days in both matrices. Matrix evaluation was performed in Hsd:Sprague Dawley®SD® rat and B6C3F1 mouse blood and mammary glands (mean %RE ≤ ±9.2; %RSD ≤ 4.3). These data demonstrate that the method is suitable for determination of AP in rodent blood and mammary glands.

October 1957, and the successful launch of Sputnik 1 into Earth orbit, marked the dawn of the Space Age. The first of the 'fellow travellers' - humanity's first artificial satellite - orbited for a mere three months before re-entering the Earth's atmosphere, though its mission paved the way for an era of exploration that has endured to the present day. For many, a world without satellites would be a difficult one to imagine. As a society, we have become reliant on them for a vast array of services and applications. With a divine view of large swathes of the Earth's surface, and the ability to relay signals around its curvature, satellites have enabled the fast transfer of data on a global scale, bypassing the challenges associated with ground-based broadcasting, long-distance wiring, and so on. Positioning, Navigation and Timing (PNT) satellites have revolutionised transportation by land, air, and sea, while weather satellites enable scientists to monitor and warn of large-scale phenomena as they develop in near real-time. Satellites have extended the frontiers of observation: looking outwards, astronomers are able to circumvent the Earth's atmosphere to look deeper into the cosmos than ever before; looking inwards, patterns and processes that feed into general circulation models can be monitored on a range of timescales, improving our understanding of climate change. Satellites, and the services they provide, are not going to disappear any time soon. That said, threats to satellite safety do exist, and it is important that they be addressed as soon as possible to avoid long-lasting damage to operations in the space domain. Nearly sixty-five years on from the advent of human activity in space, I chart the evolution of the orbital debris environment and review latest efforts to make space operations more sustainable., Comment: 9 pages, 6 figures - Invited review for Astronomy & Geophysics (RAS Journals) - Accepted for publication in Volume 63, Issue 2

Flax composites demonstrate superior damping properties to conventional fibres. These materials are already being utilised in some products but the mechanical properties they exhibit are too low for many structural applications. Hybridization of flax with higher strength fibres has been shown to yield materials, which balance damping and load carrying capabilities alongside improved environmental credentials for flax/carbon hybrids. However, the most used composite material is E-glass but the current literature does not facilitate the prediction of damping properties for these hybrid composites, where it is expected that they will behave differently due to the difference in material properties. The woven flax and E-glass fibres specimens embedded with epoxy resin are manufactured via resin infusion to understand the damping and mechanical properties possible from an industrial process and the dominant factors affecting them, rather than the relationships between individual variables and these properties. These experiments allow the hybrids to be profiled for the first time and it is observed that hybridization of flax and E-glass fibres results in an increase in damping, from 1.97% to 2.63% for the best hybrid, especially when the flax plies are placed on the outer skin, however the compromise in tensile properties is significant, from 473.28 MPa to 166.53 MPa.

Glass structures are often used in industries utilising large structural topologies. These structures are typically manufactured by post-curing subcomponents together, using a chopped strand mat layer at the interface. To predict failure of these joints requires an accurate assessment of the material and fracture properties. In this paper two industrially manufactured top-hat stiffened panels are tested to determine the fracture behaviour at the component level. This highlights that the variability seen in fracture properties at coupon level is less evident in structural component response. Then a previously developed set of material properties is used to accurately model the structural response, crack initiation and debonding of the panels under four point bend using Finite Element Analysis which gives final failure at 6.2 kN and a 4.4% error compared to the experimental results which exhibits final failure at 5.94 kN. The specific fracture properties tested and R curve are shown to be critical in assessing crack initiation and propagation with considerable error, 14.5%, provided by data assumed from the literature.

Alpha-pinene is a monoterpene found in the oil of coniferous trees and has a wide variety of applications. Alpha-pinene oxide (APO) is a potential reactive metabolite of alpha-pinene in rodents. The objective of this work is to validate a gas chromatography–mass spectrometry method to quantitate APO in rat and mouse blood and mammary glands in support of studies investigating the toxicity and toxicokinetic behavior of alpha-pinene. The method was validated in male Sprague Dawley rat blood over the concentration range of 5–250 ng/mL. Matrix standard curves were linear (r ≥ 0.99), and accuracy (percent relative error, %RE) was ≤±15% for standards at all levels. Intra- and interday precision (percent relative standard deviation, %RSD) and accuracy (%RE) were evaluated at three concentration levels (10, 50 and 200 ng/mL) and were ≤6.3% and ≤±5.4%, respectively. The limit of detection, determined from the SD of the limit of quantitation (5 ng/mL), was 1.06 ng/mL. Standards as high as 25,000 ng/mL could be accurately quantified after diluting to the validated range (%RE ≤ ±7.1%; %RSD ≤ 5.8%). APO was stable in rat blood for at least 70 days in frozen storage (−80°C). APO could accurately be quantified in male and female Hsd:Sprague Dawley® SD® rat and B6C3F1 mouse blood (mean %RE ≤ ±5.3%; %RSD ≤ 7.8%) and female B6C3F1 and Sprague Dawley rat mammary glands (mean %RE ≤ ±14.6%; %RSD ≤ 8.1%) using a primary matrix standard curve. These results demonstrate that the method is suitable for the analysis of APO in rodent blood and mammary glands generated from toxicokinetic and toxicology studies.

The COSMOS-UK observation network has been providing field scale soil moisture and hydrometeorological measurements across the UK since 2013. At the time of publication a total of 51 COSMOS-UK sites have been established, each delivering high temporal resolution data in near-real time. Each site utilises a cosmic-ray neutron sensor, which counts fast neutrons at the land surface. These measurements are used to derive field scale near-surface soil water content, which can provide unique insight for science, industry, and agriculture by filling a scale gap between localised point soil moisture and large-scale satellite soil moisture datasets. Additional soil physics and meteorological measurements are made by the COSMOS-UK network including precipitation, air temperature, relative humidity, barometric pressure, soil heat flux, wind speed and direction, and components of incoming and outgoing radiation. These near-real time observational data can be used to improve the performance of hydrological models, validate remote sensing products, improve hydro-meteorological forecasting and underpin applications across a range of other scientific fields. The most recent version of the COSMOS-UK dataset is publically available at https://doi.org/10.5285/37702a54-b7a4-40ff-b62e-d14b161b69ca (Stanley et al., 2020).

Osteoarthritis (OA) can be debilitating and career-ending for horses. Current treatments offer temporary and symptomatic relief, but potentially deleterious side effects. Bone marrow mononuclear cells (BMNC) are a rich source of macrophage progenitors that are anti-inflammatory and promote inflammation resolution. The objective of this study was to evaluate the ability of intra-articular BMNC therapy to improve clinical signs of naturally occurring equine OA. Horses presenting with clinical and radiographic evidence of moderate OA in a single joint were randomly assigned to 1 of 3 treatments: saline (negative control), triamcinolone (positive control), or BMNC (treatment group). Horses were subjectively and objectively evaluated for lameness and synovial fluid collected (cytology and cytokine/growth factor quantification) at 0, 7, and 21 days post-injection. Data were analyzed using General Estimating Equations with significance set at P

The abundance of deuterium in giant planet atmospheres provides constraints on the reservoirs of ices incorporated into these worlds during their formation and evolution. Motivated by discrepancies in the measured deuterium-hydrogen ratio (D/H) on Jupiter and Saturn, we present a new measurement of the D/H ratio in methane for Saturn from ground-based measurements. We analysed a spectral cube (covering 1151-1160 cm$^{-1}$ from 6 February 2013) from the Texas Echelon Cross Echelle Spectrograph (TEXES) on NASA's Infrared Telescope Facility (IRTF) where emission lines from both methane and deuterated methane are well resolved. Our estimate of the D/H ratio in stratospheric methane, $1.65_{-0.21}^{+0.27} \times 10^{-5}$ is in agreement with results derived from Cassini CIRS and ISO/SWS observations, confirming the unexpectedly low CH$_{3}$D abundance. Assuming a fractionation factor of $1.34 \pm 0.19$ we derive a hydrogen D/H of $1.23_{-0.23}^{+0.27} \times 10^{-5}$. This value remains lower than previous tropospheric hydrogen D/H measurements of (i) Saturn $2.10 (\pm 0.13) \times 10^{-5}$, (ii) Jupiter $2.6 (\pm 0.7) \times 10^{-5}$ and (iii) the proto-solar hydrogen D/H of $2.1 (\pm 0.5) \times 10^{-5}$, suggesting that the fractionation factor may not be appropriate for stratospheric methane, or that the D/H ratio in Saturn's stratosphere is not representative of the bulk of the planet., 9 pages, 6 figures, 1 table

This paper presents a series of model experiments on the current-induced motions of a 1:40 scale lifeboat at a single point mooring (SPM). The influence upon vessel and buoy motion of the mooring configuration factors of (a) three mooring line (hawser) lengths, (b) four buoy shapes and (c) two buoy sizes have been investigated. A motion tracking algorithm was successfully employed and validated against data from an inertial measuring unit allowing small scale testing without the influence of instrument cabling. The results show that the dominant translational motion, of the model lifeboat at a SPM, is sway and the rotational motion is yaw, with double pendulum-like fishtailing behaviour prevalent. Increasing the hawser length, when no buoy was present, resulted in an increase in the vessel's sway velocity. No significant effects on vessel motion were observed from changes in the shape of the 1:40 and 1:20 scale buoys. However, the presence and increasing size of the buoy was found to increase the sway velocity of the buoy and reduce the motions of the model lifeboat. These results suggest that changes in buoy size influence the motions of the model lifeboat which may enable mooring efficacy to be improved.

Many marine species exhibit capabilities that would be desirable for manmade systems operating in the maritime environment. However, without detracting from the potential, if bioinspiration is to prove beneficial, it is important to have a consistent set of metrics that allow fair comparison, without bias, when comparing the performance of engineered and biological systems. In this study we focus on deriving an unbiased metric of performance applicable to marine animals and engineered subsea vehicles for one of the most fundamental of properties; that of the energy cost of locomotion. We present a rational analytical model of the physics behind the total energy cost of locomotion applicable to both biological and engineered autonomous underwater marine systems. This model proposes the use of an equivalent spheroid efficiency as a fair metric to compare engineered and biological systems. The model is then utilised to identify how changes in mass, speed, spheroid efficiency and hotel load impact the performance of the system.

A screening of different hardeners derived from cashew nut shell liquid (CNSL) was performed; they were compared to a conventional hardener in an epoxy resin system for composite production by infusion process. All samples were submitted to different post-curing processes before tensile strength and moisture uptake were evaluated. It was observed that the use of CNSL hardeners produced cured epoxies similar in Young’s Modulus (YM) to the conventional hardener with a lower moisture uptake however, the hardeners resulting in a low YM had a marked reduction in moisture uptake. Studies of the post-curing process showed that the moisture uptake of the conventional system can be improved but, depending on the temperature applied, the process can be detrimental to the CNSL hardeners, provided that moisture uptake was increased after post-curing. The results indicate that biobased content can be introduced to a conventional epoxy resin system by replacing the conventional hardener commonly used by a sustainable one derived from cashew nut shell liquid with an additional moisture uptake reduction.

It is vital to be able to rapidly assess damaged ship structures. This ensures the safety of personnel and facilitation of the most effective repair or recovery. Interframe progressive collapse analysis has been used as a method for rapid assessment for vessels but its suitability for application to damaged vessels has been questioned, due to the limited failure modes assessed and modelling assumptions required when implementing the method. To reduce the cost and increase the effectiveness of the recovery of a damaged vessel, it will be important to more accurately assess the structure by determining the correct failure mode. This paper presents a study on the use of progressive collapse analysis to model damaged box girders which assesses the structure across multiple frame boundaries. The study shows that while progressive collapse analysis can be applied in the assessment of damaged box girders, implementing the newly proposed assessment allows greater accuracy in the calculation of the collapse strength through capture of the true mode of failure. This new method will allow the effects of the damage on surrounding structure to be captured which can influence the deflection shapes that will lead to collapse of the structure.

Natural fibres exhibit improved sustainability and similar mechanical properties to E-glass. However, for laminates there is a larger difference in properties and limited assessments of structural components. An analytical method for grillages is developed which is generally shown to predict the stress to within 5% of an FEA model. The simulations demonstrate a change in structural response between flax and carbon, with flax demonstrating higher stresses than expected for the lower Young’s modulus for the same topology. Flax is shown to be more sensitive to transverse Young’s modulus than standard composites and a better characterisation of this property is required.

Weather routing methods are essential for planning routes for commercial shipping and recreational craft. This paper provides a methodology for quantifying the significance of numerical error and performance model uncertainty on the predictions returned from a weather routing algorithm. The numerical error of the routing algorithm is estimated by solving the optimum path over different discretizations of the environment. The uncertainty associated with the performance model is linearly varied in order to quantify its significance. The methodology is applied to a sailing craft routing problem: the prediction of the voyaging time for an ethnographic voyaging canoe across long distance voyages in Polynesia. We find that the average numerical error is $0.396\%$, corresponding to $1.05$ hours for an average voyage length of $266.40$ hours. An uncertainty level of $2.5 \%$ in the performance model is seen to correspond to a standard deviation of $\pm 2.41-3.08\%$ of the voyaging time. These results illustrate the significance of considering the influence of numerical error and performance uncertainty when performing a weather routing study.

On 19–21 April 2013, the ground-based 10-m W.M. Keck II telescope was used to simultaneously measure View the MathML sourceH3+ emissions from four regions of Saturn’s auroral ionosphere: (1) the northern noon region of the main auroral oval; (2) the northern midnight main oval; (3) the northern polar cap and (4) the southern noon main oval. The View the MathML sourceH3+ emission from these regions was captured in the form of high resolution spectral images as the planet rotated. The results herein contain twenty-three View the MathML sourceH3+ temperatures, column densities and total emissions located in the aforementioned regions – ninety-two data points in total, spread over timescales of both hours and days. Thermospheric temperatures in the spring-time northern main oval are found to be cooler than their autumn-time southern counterparts by tens of K, consistent with the hypothesis that the total thermospheric heating rate is inversely proportional to magnetic field strength. The main oval View the MathML sourceH3+ density and emission is lower at northern midnight than it is at noon, in agreement with a nearby peak in the electron influx in the post-dawn sector and a minimum flux at midnight. Finally, when arranging the northern main oval View the MathML sourceH3+ parameters as a function of the oscillation period seen in Saturn’s magnetic field – the planetary period oscillation (PPO) phase – we see a large peak in View the MathML sourceH3+ density and emission at ∼115° northern phase, with a full-width at half-maximum (FWHM) of ∼44°. This seems to indicate that the influx of electrons associated with the PPO phase at 90° is responsible at least in part for the behavior of all View the MathML sourceH3+ parameters. A combination of the View the MathML sourceH3+ production and loss timescales and the ±10° uncertainty in the location of a given PPO phase are likely, at least in part, to be responsible for the observed peaks in View the MathML sourceH3+ density and emission occurring at a later time than the peak precipitation expected at 90° PPO phase.

Top-hat stiffened plates provide an efficient structure for engineering applications. During service debonding between the stiffener and the plate is often observed and parametric studies of open section stiffeners have shown that debond size and location have a significant effect on the damage mode of the panel. However, these studies do not consider the interaction of failure modes and do not assess the ultimate failure of the structure. In this paper top-hat stiffened composite structures are assessed considering debond damage between the stiffener and plate. A non-linear finite element model is used to perform a parametric study on the effect of both damage and the panel’s geometry on the failure modes, ultimate strength and its damage tolerance. Results show that top-hat stiffened panels exhibit a trend between ultimate strength and the debond size with crack initiation not necessarily propagating. Geometric imperfections accelerate buckling but can provide an arrest point for crack propagation.

Sulfolane is a ground water contaminant near refinery sites. The objective of this work was to investigate the toxicokinetics and bioavailability of sulfolane in male and female Harlan Hsd:Sprague Dawley® SD® rats and B6C3F1/N mice following a single oral administration of 10, 30, or 100 mg/kg. Sulfolane was rapidly absorbed in rats with the maximum plasma concentration, C(max), reached at ≤ 1.47 h. Although C(max) increased proportionally to the dose, the half-life of elimination increased with the dose and the area under the concentration versus time curve (AUC) increased more than proportionally to the dose. In male and female rats, plasma elimination half-life increased with the dose from 1.97 to 6.33 h. Absorption of sulfolane in mice following oral administration was more rapid than in rats with C(max) reached at ≤ 0.55 h. In addition, mice had a shorter half-life (≤ 1.25 h) and a lower AUC than rats. In male and female mice, both C(max) and AUC increased more than proportionally to the dose. Bioavailability of sulfolane was higher in rats (81–83%) than mice (59–63%) at 10 mg/kg; at 30 and 100 mg/kg, bioavailability > 100% in both species and sexes suggesting that the saturation of metabolism and clearance processes of sulfolane may begin at a single oral dose of ~30 mg/kg. There was no apparent sex difference in toxicokinetic parameters of sulfolane in rats and mice. These data demonstrate that sulfolane was well-absorbed following oral administration with high bioavailability in rats and mice with some species differences, but no sex difference.

The viability of a novel sustainable polymeric composite material, based on photocurable linseed oil resin was explored, with a view to exploiting its potential in marine environments. The study focused on a UV-curable resin subjected to setting through photoinitiated cationic polymerisation. Deployment of heterogeneous solid catalysts, containing isolated Brønsted acid centres, further improved the efficiency of cationic polymerisation, leading to enhanced thermal stability and water resistance. These features are highly desirable in the design of composite resins for marine applications. A wide range of spectroscopic, calorimetric and thermogravimetric methods as well as computational simulations have been employed to study the physico-chemical characteristics of the resin and its resistance to black and grey waste, UV resistance and hygrothermal ageing. The findings have revealed that, unlike conventional epoxy resins, the ELO resin demonstrated no decrease in glass transition temperature, Tg, despite having been exposed to different methods of ageing. In addition, the water molecules that are absorbed by the resin during hygrothermal ageing have been found to be structurally-bound through hydrogen bonding, which is supported by initial computational studies. The structure–property correlations that have been derived help to better understand the ageing process, which could be beneficial in predicting the lifetimes of these sustainable polymeric composite materials and consequently developing novel chemical methods for improving their durability and stability.

We present an analysis of recent high spatial and spectral resolution ground-based infrared observations of H3+ obtained with the 10-m Keck II telescope in April 2011. We observed H3+ emission from Saturn’s northern and southern auroral regions, simultaneously, over the course of more than 2 h, obtaining spectral images along the central meridian as Saturn rotated. Previous ground-based work has derived only an average temperature of an individual polar region, summing an entire night of observations. Here we analyse 20 H3+ spectra, 10 for each hemisphere, providing H3+ temperature, column density and total emission in both the northern and southern polar regions simultaneously, improving on past results in temporal cadence and simultaneity. We find that: (1) the average thermospheric temperatures are 527 ± 18 K in northern Spring and 583 ± 13 K in southern Autumn, respectively; (2) this asymmetry in temperature is likely to be the result of an inversely proportional relationship between the total thermospheric heating rate (Joule heating and ion drag) and magnetic field strength – i.e. the larger northern field strength leads to reduced total heating rate and a reduced temperature, irrespective of season, and (3) this implies that thermospheric heating and temperatures are relatively insensitive to seasonal effects.

The intensity of H3+ emission can be driven by both temperature and density, and when fitting a set of infrared H3+ line spectra, an anticorrelation between the fitted temperatures and densities is commonly observed. The ambiguity present in the existing published literature on how to treat this effect puts into question the physical significance of the derived parameters. Here, we examine the nature of this anticorrelation and quantify the inherent uncertainty in the fitted temperature and density that this produces. We find that the uncertainty produced by the H3+ temperature and density anticorrelation is to a very good approximation equal to the uncertainties that are derived from the fitting procedure invoking Cramer's rule. This means that any previously observed correlated variability in the observed H3+ temperature and density outside these errors, in the absence of other error sources, are statistically separated and can be considered physical. These results are compared to recent ground-based infrared Keck Near InfRared echelle SPECtrograph (NIRSPEC) observations of H3+ emission from Saturn's aurora, which show no clear evidence for large-scale radiative cooling, but do show stark hemispheric differences in temperature.

In this paper, the effect of hygrothermal ageing on the flexural properties of glass/epoxy, glass/linseed oil and glass/castor oil composites is reported. Plant oil based resins offer renewable and potentially less toxic alternatives to conventional largely petroleum based marine composites. The long-term performance of these novel composites needs to be investigated and understood before using them in structural applications. In this research it was found that in the unaged condition, the flexural properties of glass/epoxy were significantly higher than both glass/castor oil and glass/linseed oil composites. After ageing in water at 40 °C for 46 weeks, the properties of glass/castor oil were comparable to glass/epoxy while the properties of glass/linseed oil were remarkably lower. The decrease in glass/linseed oil performance was explained in terms of the changes in the failure modes caused by moisture uptake.

The design process is becoming increasingly complex with designers balancing societal, environmental and political issues. Composite materials are attractive to designers due to excellent strength to weight ratio, low corrosion and ability to be tailored to the application. One problem with composite materials can be the low stiffness that they exhibit and as such for many applications they are stiffened. These stiffened structures create a complex engineering problem by which they must be designed to have the lowest cost and mass and yet withstand loads. This paper therefore examines the way in which rapid assessment of stiffened boat structures can be performed for the concept design stage. Navier grillage method is combined with genetic algorithms to produce panels optimised for mass and cost. These models are constrained using design rules, in this case ISO 12215 and Lloyd's Register Rules for Special Service Craft. The results show a method that produces a reasonable stiffened structure rapidly that could be used in advanced concept design or early detailed design to reduce design time.

We compared expert and novice behaviour in a group of participants as they engaged in a simulated maritime driving task. We varied the difficulty of the driving task by controlling the severity of the sea state in which they were driving their craft. Increases in sea severity increased the size of the upcoming waves while also decreasing the distance between consecutive waves. Expert participants drove their craft at a higher speed than novices, and decreased their fixation durations as wave severity increased. Furthermore, the expert participants increased the horizontal spread of their fixation positions as wave severity increased to a greater degree than novices. Conversely, novice participants showed evidence of a greater vertical spread of fixations than experts. By connecting our findings with previous research investigating eye movement behaviour and road driving, we suggest that novice or inexperienced drivers show inflexibility in adaptation to changing driving conditions.

In this paper a C° four node flat facetted shell element with drilling rotational degrees of freedom based on a first order shear deformation shell theory is developed to study the transient response of initially stressed composite sandwich folded plates. The new shell element contains three translations, two rotations of the normals about the shell mid-plane, and one drilling rotational degree of freedom per node. A consistent mass matrix formulation is employed to evaluate the total kinetic energy of the system. A generic validation study is carried out to evaluate the performance of the present finite element formulation. New results are presented for the transient analysis of initially stressed composite sandwich folded plate structures.

Boatbuilding is a growth market with global competition and tight profit margins. Concurrent engineering is not presently prevalent within the boatbuilding industry and yet this is a technique that has found much success in other industries. A methodology has, therefore, been developed to aid design in the leisure boatbuilding industry. This environment uses collaborative engineering and automated communication to aid the passing of direct communication between all members of the design team. This paper determines the characteristics of importance within boatbuilding and relates these to a framework concurrent engineering environment aimed specifically at this industry. The current work focuses on the structural and production subsystems in an attempt to improve design for production. The use of concurrent engineering tools has been highlighted with an example.

On 21 April 2013, during a co-ordinated Saturn auroral observing campaign, the northern and southern poles of the planet were observed from the Earth using the NASA Infrared Telescope Facility (IRTF), Keck, and Hubble Space Telescope (HST) simultaneously with the Cassini infrared, visible, and ultraviolet remote sensing instruments. We present simultaneous multi-scale and multi-wavelength analysis of the morphology of auroral emissions at Saturn. The visible main auroral emission vary between ∼∼2 and 10 kR on timescales of minutes and across spatial scales of down to ∼∼14 km on the planet. The H2 Far Ultraviolet (FUV) brightness varies by a factor of ∼∼10, from ∼∼4–40 kR, over timescales of 1 min and spatial scales of 720 km. View the MathML sourceH3+ infrared emissions vary less than the H2 emissions, from ∼∼5–10 μμW m−2 sr−1, over similar spatial scales (∼∼300 km) and timescales of a few seconds to a few hours. The fine-scale temporal and spatial features seen in the main oval show that complex structures are present even during quiet solar wind conditions. Diffuse ultraviolet emissions southward of the southern midnight main oval that are not seen in the infrared, implying a steep temperature gradient of ∼∼50 K over 2–4°° latitude equatorward of the main oval. Dynamics on scales of ∼∼100 km at the poles are revealed by lower spatial resolution observations, the morphologies of which are partly consistent with overlapping local-time fixed and co-rotating current systems. We also present the first direct comparison of simultaneous infrared, visible, and ultraviolet auroral emissions at Saturn. Finally, the main auroral emissions are found to be approximately co-located in the midnight sector, forming an arc with a width of ∼∼0.5–1°°, at 72–74° southern latitude, moving slightly equatorward with increasing local-time.

Due to environmental challenges it is important to investigate potentially more sustainable new materials, including natural fibre reinforced composites. Whilst a number of natural reinforcements show promise there is a concern that laminate properties are too difficult to predict due to the lack of uniformity in natural fibres. The paper quantitatively evaluates the high variability observed at yarn scale, at cloth scale, which shows significant decreases, and at laminate scale, showing comparable variability to synthetic based composites. This demonstrates that natural fibre reinforced composites have reproducible properties at the macroscale level and provides a pathway to application in industry.

In an unpredictable world where human intervention or unexpected environmental conditions can prevail, damage can occur to manmade structures. Whilst structural design allows for redundancy, or a structural capability beyond the general working load of the structure, it is necessary to be able to analyse and understand the residual capability of a damaged structure to ensure the safety of personnel in the vicinity of the structure and assess the potential to facilitate repair.Idealised Structural Unit Method (ISUM) can allow rapid assessment of large structural arrangements by simplification into smaller constituent parts, which are assessed against pre-calculated failure data for each part. The method has potential benefits for allowing rapid assessment of damaged steel-plated structure that would otherwise require the use of high fidelity modelling of the entire structures, such as through the use of finite element analysis.This paper presents a study on the use of ISUM to assess damaged steel-plated structures and its limitations through the collapse analysis of stiffened steel panels. A new ISUM is proposed for strength assessment of damaged structural arrangements. Analysis is undertaken to assess the effects of geometrical and material property variations that can occur in a structure as well as the effects of damage aperture size and shape on the collapse strength of stiffened steel panels. The study shows that while ISUM can be applied in the assessment of damaged steel-plated structures, implementing the proposed new ISUM allows greater accuracy in the calculation of the collapse strength of damaged stiffened steel panels. The paper also concludes that the assessment of larger structural units for application in the ISUM assessment, will allow the effects of the damage on surrounding structure to be captured, which can influence the deflection shapes that will lead to collapse of the structure.

Some species of fish are able to alter their mode of swimming to interact with naturally produced vortices; the use of these gaits reduces the energy expended by the fish. To analyse the feasibility of autonomous underwater vehicles replicating these gaits, a series of experiments are performed with unpowered rigid and flexible bodies positioned in the Kármán wake of a rigid cylinder. Simple motion capture techniques are used to capture the bodies’ lateral and upstream motion in the flow. The results demonstrate that manufactured bodies are capable of passively mimicking fish behaviours, to a limited extent. More importantly, it was concluded that while significant upstream movement was possible for a manufactured object, it was achievable irrespective of the stiffness of the material. For autonomous underwater vehicles operating in unsteady flow regimes, an ability to utilise energy-saving gaits may improve the range or operational time.

The use of composite laminate materials has increased rapidly in recent years due to their excellent strength to weight ratio and resistance to corrosion. In the construction of marine vessels, stiffened plates are the most commonly used structural elements, forming the deck, bottom hull, side shells and bulkheads. This paper presents the use of a stochastic approach to the design of stiffened marine composite panels as part of a current research programme into developing stochastic methods for composite ship structures, accounting for variations in material properties, geometric indices and processing techniques, from the component level to the full system level. An analytical model for the solution of a stiffened isotropic plate using a grillage analogy is extended by the use of equivalent elastic properties for composite modelling. This methodology is applied in a reliability analysis of an isotropic (steel) stiffened plate before the final application for a reliability analysis for a FRP composite stiffened plate.

Parametric variation and optimisation using genetic algorithms employing single and multi-objective functions are proposed for the optimisation of a structural steel/composite connection. The joint in marine applications is the connection between the steel hull and the composite superstructure of a naval vessel. A baseline joint is defined and all parametric variations and optimised joints are compared to this. The parametric results provided design curves of the joint performance determined from the weight, Von Mises stress in the adhesive and the global stiffness indicating performance sensitivity to specific changes in the joint geometry. The results indicated that the parametric variations can lead to an improvement in the performance but high levels of human interaction are required to make a combined improvement to the performance. The use of genetic algorithms provided an efficient method of searching the design space for an optimal joint. The single objective function provides an excellent reduction in the weight and maintaining or improving the performance of the joint to in-plane compressive loading. The use of the multi-objective function whereby a weighting was applied to the weight, stress and stiffness performance criteria proved extremely successful in further optimising the joint. The use of genetic algorithms has been demonstrated to efficiently search the complex design space of a structural connection and the use of multi-objective functions as the most effective selection method.

Accurate prediction of the motions of high-speed craft is an essential element in understanding the response of crew to a particular design configuration. The aim of this work is to evaluate the capability of a numerical method for use in the context of a procedure for designing high-speed craft. A numerical model is used to predict the motions of a planing craft in regular waves. The model is based on non-linear strip theory, through calculation of the forces occurring on wedge impact. This numerical model and its limitations are well understood for lower planing speeds (up to a length-based Froude number of around 1.2). This paper describes the limitations and accuracy for higher-speed craft (Froude number around 3). At present there is an inadequate knowledge of the model performance at these speeds. Validation of the model is achieved using experimental data obtained from testing two scale models: A wave piercing rigid inflatable boat (RIB) and an Atlantic 21 RIB. The experiments are conducted in a range of regular wave frequencies for three wave heights. Results are promising, with good correlation between the heave motion of the numerical model and the measured experimental data. Based on these results, a number of potential enhancements to the existing numerical model are discussed.

We present the first detailed analysis of H3+ nightside emission from Jupiter, using Visual and Infrared Mapping Spectrometer (VIMS) data from the Cassini flyby in 2000–2001, producing the first Jovian maps of nightside H3+ emission, temperature, and column density. Using these, we identify and characterize regions of H3+ nightside emission, compared against past observations of H3+ emission on the dayside. We focus our investigation on the region previously described as “mid-to-low latitude emission,” the source for which has been controversial. We find that the brightest of this emission is generated at Jovigraphic latitudes similar to the most equatorward extent of the main auroral emission but concentrated at longitudes eastward of this emission. The emission is produced by enhanced H3+ density, with temperatures dropping away in this region. This emission has a loose association with the predicted location of diffuse aurora produced by pitch angle scattering in the north, but not in the south. This emission also lays in the path of subrotating winds flowing from the aurora, suggesting a transport origin. Some differences are seen between dayside and nightside subauroral emissions, with dayside emission extending more equatorward, perhaps caused by the lack of sunlight ionization on the nightside, and unmeasured changes in temperature. Ionospheric temperatures are hotter in the polar region (~1100–1500 K), dropping away toward the equator (as low as 750 K), broadly similar to values on the dayside, highlighting the dominance of auroral effects in the polar region. No equatorial emission is observed, suggesting that very little particle precipitation occurs away from the polar regions.