Category Archives: Uncategorized

Distancing ourselves from each other

Image of a person behind a camera‘The camera lens was our way of disengaging from each other, distancing ourselves from each other’s emotions.’ At the moment, we are using the camera lens in our computer or mobile phone to distance ourselves physically from colleagues, friends and relatives in order to hinder the spread of coronavirus. However, the camera lens also allows us to disengage emotionally from one another as JG Ballard wrote thirty years ago in his novel called ‘The Kindness of Women‘ from which the opening sentence is taken.  It is relatively easy to avoid giving emotional cues to your interlocutor when they can only see a flat image of your face.  I am unsure whether JG Ballard would have anticipated our virus-induced socially-distanced world but he would certainly have recognised the rather flat discussions that we tend to have in our internet meetings.

Source: JG Ballard, The Kindness of Women, London: Fourth Estate, 2014 (first published 1991).

Image from StockSnap

Season’s greetings in 2020

Zahrah Resh Abstract paintingMy posts at Christmas time in the past have often been pictures of snowy scenes or Christmas trees. This year I have gone for something different. The image above is an abstract painting by Zahrah Resh.  I have used extracts from it as thumbnails in four posts over the last three months and so I thought it was about time to show you the whole painting.  Zahrah Resh is a contemporary American abstract artist based in East Lansing, Michigan who has exhibited at the ArtPrize which takes place over 19 days in Grand Rapids, Michigan attracting around half a million visitors.  ArtPrize started in 2009 and offered the world’s largest art prize of $250,000. We got to know Zahrah when we lived nearby in Okemos, Michigan and we brought a number of her paintings back to England when we moved to Liverpool nearly a decade ago.  They remind me of the people we met and knew during our time in Michigan.  Best wishes for happiness, joy and peace this holiday.

If you are missing the snowy scenes then see  ‘Digital detox‘ on December 27th, 2016 or ‘Season’s greetings‘ on December 24th, 2014; or if you prefer Christmas trees then see ‘Happy Christmas‘ on December 25th, 2019] or ‘Season’s greeting‘ on December 27th, 2017.

And if you missed the posts with the thumbnails that were extracts from the above, or you are just looking for something interesting to read, then see ‘Puzzles and mysteries‘ on November 25th, 2020; ‘Digital twins could put at risk what it means to be human‘ on November 18th, 2020; and ‘Lacking creativity‘ on October 28th, 2020.

A daily routine

I have been writing a weekly post for this blog since January 2013.  That’s more than 400 posts, which I thought sounded pretty impressive until I read about the Gentle Author who has been publishing daily since 2010 on spitalfieldslife.com.  That’s more than 4000 stories; so, I am not prolific by comparison.  And, the Gentle Author has promised to post 10,000 pieces which apparently will take until 2037.  I am unsure whether I will still be writing a weekly post in 2037 or even 2027; but, I plan to carry on for the moment.  Last week I read about another daily routine that has been sustained for nearly 40 years by Nancy Floyd.  She has been taking a daily photograph of herself since 1982 and plans to continue to her deathbed.  Her self-portrait series is available on her website and was recently featured in the FT Weekend magazine on August 8/9, 2020.  On the one hand, I am in awe of people who have the self-discipline to maintain such a daily activity; while on the other hand, I feel that there is too much I want to do and think about to stop everyday to take time out to write a blog post or snap a self portrait.  The photograph shows a portrait of me taken by my youngest daughter earlier this month – perhaps the first in series.

Potential dynamic buckling in hypersonic vehicle skin

The skin of an aircraft is supported on the inside by a network, or mesh, of ribs and stringers running approximately at right angles to one another; so that the skin is effectively a series of rectangular plates supported around their edges.   In hypersonic flight, above five times the speed of sound, these rectangular plates are subject to vibration and to high temperatures that vary spatially and with time.  The combined vibratory and thermal loading causes the plates to buckle out of plane which has two possible detrimental consequences: first, it causes the formation of fatigue cracks leading to catastrophic failure; and, second, it might influence the formation of the boundary layer in the flow over the skin of the aircraft and affect the aerodynamics of the aircraft.  In my laboratory, we have built a test-rig that allows us to subject rectangular plates to random mechanical vibrations up to 1000Hz and, at the same time, to temperature distributions upto 1000K that vary in time and space.  Earlier this year, we published an article in which we showed, by experiment, that an edge-reinforced rectangular plate behaved as a dynamic system in response to thermal loading.  In other words, when a constant temperature distribution is applied, the shape of the plate varies with time until an equilibrium state is achieved.  In addition, we found that the post-buckled shape of the plate is not proportional to the energy supplied but dependent on the in-plane temperature distribution.  Probably, both of these observed behaviours are a result of differential thermal expansion of the plate and its reinforcements.

The image shows point-wise temperature and displacement measurements (centre) at the centre and edge of a reinforced plate (top) subject to a localised strip of heating over time as shown by the temperature distributions (bottom).

This is the fourth in a series of posts on recent work published by my research group.  The others are: ‘Salt increases nanoparticle diffusion‘ on April 22nd, 2020; ‘Spatio-temporal damage maps for composite materials‘ on May 6th, 2020; and, ‘Thinking out of the box leads to digital image correlation through space‘ on June 24th, 2020.

Source:

Santos Silva AC, Lambros J, Garner DM & Patterson EA, Dynamic response of a thermally stressed plate with reinforced edges, Experimental Mechanics, 60:81-92, 2020.