Tributes to G.E. Steward

https://digitalcommons.acu.edu/crs_books/1231/thumbnail.jp

On the locus formed by the maximum heights of projectile motion with air resistance

We present an analysis on the geometrical place formed by the set of maxima of the trajectories of a projectile launched in a media with linear drag. Such a place, the locus of apexes, is written in term of the Lambert $W$ function in polar coordinates, confirming the special role played by this function in the problem. In order to characterize the locus, a study of its curvature is presented in two parameterizations, in terms of the launch angle and in the polar one. The angles of maximum curvature are compared with other important angles in the projectile problem. As an addendum, we find that the synchronous curve in this problem is a circle as in the drag-free case.Comment: 7 pages, 6 color eps figures. Synchronous curve added. Typos and style corrected

Cooldown of Cryogenic Transfer Lines an Experimental Report

Pressure, temperature, and flow during cooldown of cryogenic transfer line

People should be allowed to do what they like’: Autistic adults’ views and experiences of stimming

This is the final version. Available from the publisher via the DOI in this record.Data from participants who consented will be deposited in the UK Data Service, in 2019.‘Stereotyped or repetitive motor movements’ are characterised as core features in the diagnosis of autism, yet many autistic adults (and the neurodiversity movement) have reclaimed them as ‘stimming’. Supported by a growing body of scientific research, autistic adults argue that these behaviours may serve as useful coping mechanisms, yet little research has examined stimming from the perspective of autistic adults. Through interviews and focus groups, we asked 32 autistic adults to share their perceptions and experiences of stimming, including the reasons they stim, any value doing so may hold for them and their perceptions of others’ reactions to stimming. Using thematic analysis, we identified two themes: stimming as (1) a self-regulatory mechanism and (2) lacking in social acceptance, but can become accepted through understanding. Autistic adults highlighted the importance of stimming as an adaptive mechanism that helps them to soothe or communicate intense emotions or thoughts and thus objected to treatment that aims to eliminate the behaviour.Wellcome TrustLeverhulme Trus

Verbs, times and objects

The aim of the paper is to demonstrate the fruitfulness of the influential verb typology developed by Zeno Vendler for recent debates in the philosophy of perception. Section one explains the verb typology and explains how Vendler applies it to different perceptual notions. Section two identifies various questions that arise from observations in Vendler’s paper that suggest that there is a match between the temporal properties of perceptual verb objects and the complex verb phrases of which they are a part. Subsequent discussion focuses on just one of these questions. Section three identifies and rejects a simple proposal about how to answer this question. Section four develops a ‘limited matching’ account. In the visual perception of events and processes there seems to be a match between the temporal duration, order and location of the events and processes which are the objects of perception and the subject’s perceiving them. But this matching is absent in cases of the perception of primary substances; objects which manifestly endure over time. Section five identifies and responds to some criticisms of this matching account. The conclusion notes some consequences of the discussion for contemporary debates about the temporal characteristics of perception

Coupled Numerical Analysis of Variations in the Capacity of Driven Energy Piles in Clay

Energy piles are an emerging alternative for the reduction of energy consumption to heat and cool buildings. Most of the research to date has focused on thermodynamic properties or axial and radial stress and strain of piles. This paper focuses on the effects of temperature fluctuation on the capacity of driven energy piles in clayey soils. Consolidation of clay surrounding driven piles affects the pile capacity (i.e., set up in clay). The heating and cooling periods of energy piles can create the excess pore-water pressure (EPWP, ue) or relax the existing one (e.g., due to pile driving or previous thermal loads) in clayey soils (due to the contraction and expansion of water) affecting the pile capacity. In the meantime, the thermal expansion and contraction of the pile also generate or relax the EPWP in the soil, which can be computed using the cavity-expansion theory. This paper studies the resulting changes in the pile capacity due to the daily and seasonal thermal cycles. The results show that thermal cycles in an energy pile can cause a decrease in the pile capacity leading to a delay in reaching the capacity after a complete clay set up

Validity and reliability of short‐term heart‐rate variability from disposable electrocardiography leads

BACKGROUND AND AIMS: Single‐use electrocardiography (ECG) leads have been developed to reduce healthcare‐associated infection. This study compared the validity and reliability of short‐term heart rate variability (HRV) obtained from single‐use disposable ECG leads. METHODS: Thirty healthy subjects (33 ± 10 years; 9 females) underwent 5‐min resting HRV assessments using disposable (single use) ECG cable and wire system (Kendall DL™ Cardinal Health) and a standard, reusable ECG leads (CardioExpress, Spacelabs Healthcare). RESULTS: Intraclass correlation coefficient (ICC) with 95% confidence interval (CI) between disposable and reusable ECG leads was for the time domain [R‐R interval (ms); 0.99 (0.91, 1.00)], the root mean square of successive normal R‐R interval differences (RMSSD) (ms); 0.91 (0.76, 0.96), the SD of normal‐to‐normal R‐R intervals (SDNN) (ms); 0.91 (0.68, 0.97) and frequency domain [low‐frequency (LF) normalized units (nu); 0.90 (0.79, 0.95), high frequency (HF) nu; 0.91 (0.80, 0.96), LF power (ms(2)); 0.89 (0.62, 0.96), HF power (ms(2)); 0.90 (0.72, 0.96)] variables. The mean difference and upper and lower limits of agreement between disposable and reusable leads for time‐ and frequency‐domain variables were acceptable. Analysis of repeated measures using disposable leads demonstrated excellent reproducibility (ICC 95% CI) for R‐R interval (ms); 0.93 (0.85, 0.97), RMSSD (ms); 0.93 (0.85, 0.97), SDNN (ms); 0.88 (0.75, 0.95), LF power (ms(2)); 0.87 (0.72, 0.94), and HF power (ms(2)); 0.88 (0.73, 0.94) with coefficient of variation ranging from 2.2% to 5% (p > 0.37 for all variables). CONCLUSION: Single‐use Kendall DL™ ECG leads demonstrate a valid and reproducible tool for the assessment of HRV