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A holistic approach for multi-objective design of experiment, model discrimination, and self-optimization of batch and continuous crystallization processes [Abstract]
A holistic approach for multi-objective design of experiment, model discrimination, and self-optimization of batch and continuous crystallization processes [Abstract]</p
'Wet Paint 2': Visual culture in a changing Britain - a roundtable debate
Towards the end of 2014 the previous editor of Visual Culture in Britain invited a variety of authors to contribute a page or two to a roundtable discussion on a variety of political and cultural events and changes. We solicited contributions from representatives of the British Universities, the Museum sector and Research Centres to respond to this idea of a changing Britain through the prism of British art and visual culture, using cogent examples wherever possible, and bringing to the fore the authors observations, understandings and positions within this rapidly developing context. For the re-launch of Visual Culture in Britain, the editors have invited, via the same process we went through in 2014, amounting to a series of ‘reflections on Visual Culture in Britain now, the role of journal to address some of these reflections, especially in an era of political upheaval and economic duress. To this end, what does Britain look like and how do we see these shifting landscapes through a multiplicity of mediums.’ This covers, of course, a sometime dramatic and often troubling context including, for example, the manipulation of Brexit, the murder of Jo Cox, the fire in Grenfell Tower, the escalation of Russian attacks in UK and elsewhere, the fires in the cathedral of Notre Dame and The Glasgow School of Art, Jeremy Corbyn and Boris Johnson’s leaderships, Coronavirus, lockdown, protestors’ removal of the statue of Edward Colston, the death or downfall of UK monarchical figures, 2021’s warmest New Year’s Eve on record and so on. Any tone was admissible, rhetorical, humorous, discursive, contemplative, argumentative etc…</p
Resonant fully dielectric metasurfaces for ultrafast terahertz pulse generation
Metasurfaces represent a new frontier in materials science paving for unprecedented methods of controlling electromagnetic waves, with a range of applications spanning from sensing to imaging and communications. For pulsed terahertz (THz) generation, metasurfaces offer a gateway to tuneable thin emitters that can be utilized for large-area imaging, microscopy, and spectroscopy. In literature, THz-emitting metasurfaces generally exhibit high absorption, being based either on metals or on semiconductors excited in highly resonant regimes. Here, the use of a fully dielectric semiconductor exploiting morphology-mediated resonances and inherent quadratic nonlinear response is proposed. This system exhibits a remarkable 40-fold efficiency enhancement compared to the unpatterned at the peak of the optimized wavelength range, demonstrating its potential as a scalable emitter design.</p
On the role of friction modifier additives in the oil control ring and piston liner contact
In-cylinder internal combustion engine parasitic frictional losses continue to be an area of interest to improve efficiency and reduce emissions. This study investigates the frictional behaviour at the oil control ring-cylinder liner conjunction of lubricants with anti-wear additives, varying dispersant concentration and a range of friction modifiers. Experiments are conducted at a range of temperatures on a cylinder liner with a nickel silicon carbide coating. A novel motored reciprocating tribometer, with a complete three-piece oil control ring and cylinder liner, was used to isolate the friction at the segment-liner interfaces. Four lubricants were tested, three with the same 3% dispersant concentration and 1% ZDDP anti-wear additive: the first with no friction modifier, the second with inorganic friction modifier (molybdenum dithiocarbamates), and the third with organic friction modifier (amide). A fourth lubricant with organic friction modifier with a 9% dispersant concentration was tested to compare the effect of the level of dispersant with the friction modifier. Results indicate that the inorganic friction modifier reduces friction comparatively to the other lubricants, showing the importance of friction modifier selection with anti-wear additives.</p
The rain, the river and the lake
The river feeds into the lake. The lake depends on the river and the river depends on the rain. This explains that for any development work to happen it relies on people, here being represented by the rain. The river represents the information that many organisations bring to the people. The lake symbolises the community, and how all the information that organisations bring to the people might sometimes be overwhelming to the carriers, such that at times it becomes difficult to share. When the river overflows then it becomes challenging for the community to utilize such information. Most of the time, organisations rely on a few gatekeepers in the community without reaching down to the core people within the community.Created in Mangochi District, Malawi, 2024This object is part of the Metaphors for Un/Making CSC Collection.</p
Influencing alertness through remote coaching for professional drivers
This paper presents a focused look at findings related to driver fatigue from Use Case A (UCA) of EU project PANACEA (grant agreement number 953426). UCA considers safety drivers of autonomous shuttles. For safety and regulation reasons all shuttles have a driver present ready to intervene if needed. In practice, this means that the safety driver is responsible for ensuring the safety of both passengers and surrounding road users. 8 shuttle safety drivers (100% of those available) participated. Subjective driver sleepiness was reported daily at the start and end of each shift using the Karolinska Sleepiness Scale. Potential risk for driver sleepiness was calculated using the Bordeaux Sleepiness Scale (BOSS). Overall, sleepiness was a rare experience (mean KSS start shift = 3, mean KSS end shift = 3.1). However, those identified as potentially at-risk using BOSS had some experiences of sleepiness (KSS=7) on some shifts. The PANACEA system uses input from sensors in the vehicle, workplace depot and on the driver, creating a holistic monitoring and assessment system. This detects professional drivers who are not fit to drive and supports them and their employers to manage the situation and adopt preventive measures.</p
Synoptic conditions conducive for compound wind-flood events in Great Britain in present and future climates
Extreme wind is the main driver of loss in North-West Europe, with flooding being the second-highest driver. These hazards are currently modelled independently, and it is unclear what the contribution of their co-occurrence is to loss. They are often associated with extra-tropical cyclones, with studies focusing on co-occurrence of extreme meteorological variables. However, there has not been a systematic assessment of the meteorological drivers of the co-occurring impacts of compound wind-flood events. This study quantifies this using an established storm severity index (SSI) and recently developed flood severity index (FSI), applied to the UKCP18 12km regional climate simulations, and a Great Britain (GB) focused hydrological model. The meteorological drivers are assessed using 30 weather types, which are designed to capture a broad spectrum of GB weather. Daily extreme compound events (exceeding 99th percentile of both SSI and FSI) are generally associated with cyclonic weather patterns, often from the positive phase of the North Atlantic Oscillation (NAO+) and Northwesterly classifications. Extreme compound events happen in a larger variety of weather patterns in a future climate. The location of extreme precipitation events shifts southward towards regions of increased exposure. The risk of extreme compound events increases almost four-fold in the UKCP18 simulations (from 14 events in the historical period, to 55 events in the future period). It is also more likely for there to be multi-day compound events. At seasonal timescales years tend to be either flood-prone or wind-damage-prone. In a future climate there is a larger proportion of years experiencing extreme seasonal SSI and FSI totals. This could lead to increases in reinsurance losses if not factored into current modelling.</p
Bicycle disc brake thermal management using modular ducting
Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024)
Bicycle brakes are stressed during fast downhill descents and during emergency stops. Prolonged descents, especially at high altitudes or temperatures (low air density) can create excessive brake component temperatures that may lead to overheating and brake fluid boiling, resulting in reduced braking. Previous work has modeled disc brake heating via CFD, dynamometer testing, and downhill tests in order to understand the transient thermal system response and convective heat transfer. In the work here, a modular ducting system to enhance cooling has been designed and evaluated using computational fluid dynamics (CFD). </p
Vibrations in cycling, state of the art and future outlook
Engineering of Sport 15 - Proceedings from the 15th International Conference on the Engineering of Sport (ISEA 2024)
Road cycling is an endurance sport that requires athletes and enthusiasts to cycle for long time. Thus, comfort plays an important role in the design of bicycles and cycling garments. Vibrations represent one of the most common cause of discomfort. Famous cycling competitions, such as the Paris-Roubaix, are characterized by uneven road surface that induces vibrations, thus increasing the difficulty of the race. On a physiological level, Sperlich et al., demonstrated that the presence of vibrations in cycling lead to an increased oxygen uptake at higher loads. Besides downgrading performances, long-term exposure to vibrations can lead to disorders. Therefore, it is of fundamental importance to investigate vibration and their transmission to the bicycle and the cyclist. This work aims to review the state of the art in the field of cycling vibration and identify the need for future studies. </p
Supplementary information files for Non-KAM classical chaos topology for electrons in superlattice minibands determines the inter-well quantum transition rates
(c) the Authors, CC-BY 4.0Supplementary files for article Non-KAM classical chaos topology for electrons in superlattice minibands determines the inter-well quantum transition ratesWe investigate the quantum-classical correspondence for a particle tunnelling through a periodic superlattice structure with an applied bias voltage and an additional tilted harmonic oscillator potential. We show that the quantum mechanical tunnelling rate between neighbouring quantum wells of the superlattice is determined by the topology of the phase trajectories of the analogous classical system. This result also enables us to estimate, with high accuracy, the tunnelling rate between two spatially displaced simple harmonic oscillator states using a classical model, and thus gain new insight into this generic quantum phenomenon. This finding opens new directions for exploring and understanding the quantum-classical correspondence principle and quantum jumps between displaced harmonic oscillators, which are important in many branches of natural science.</p