SpaceX discover wonders of steel rocket skins

When SpaceX started fabricating the top portion of a space ship from steel, and building it exposed to the elements rather than in a hanger, contracting a company that normally builds water towers, people speculated that it was just a mock-up because their “Hopper” is a development platform, not intended to do into space. However as more details have been revealed it seems like this is a first step for SpaceX in using stainless steel for a reusable rocket. Here they use an Austenitic Stainless steel, a material suitable for use at cryogenic temperatures and with a greater temperature capability than aluminium. A particular advantage may be the lower thermal conductivity, since it is intended to have heat tiles attached to the outside,

https://www.popularmechanics.com/space/rockets/a25953663/elon-musk-spacex-bfr-stainless-steel/

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McNamara and the story of Forrest gump

The Project 100,000 “new standards program” commenced by Robert McNamara in 1966 drafted 100,000 men formally rejected as they fell in the lower 30 percentile in the Armed Forces Qualification Test, failing tests for mental and education standards. The story of Forrest Gump was to be shared by around 100,000 men per year, colloquially labelled as McNamara’s morons, men who would be an asset to the army as they could be trained using modern methods such as video tape to bring them up to speed.

Although the mental standards where lowered to increase the numbers drafted without having to draft college educated men and the national reserve, the standards were still slightly higher than the entrance standards during the Korean war.

Hamilton Gregory talks about his book McNamara’s folly discussing the programme:

Presentation about predatory publishers

Predatory publishers named and shamed by journalists presenting at technology conference DEFCON 26

Svea, Suggy, Till – Inside the Fake Science Factory (published 17th September)

Fake News has got a sidekick and it’s called Fake Science. This talk presents the findings and methodology from a team of investigative journalists, hackers and data scientists who delved into the parallel universe of fraudulent pseudo-academic conferences and journals; Fake science factories, twilight companies whose sole purpose is to give studies an air of scientific credibility while cashing in on millions of dollars in the process. Until recently, these fake science factories have remained relatively under the radar, with few outside of academia aware of their presence; but the highly profitable industry is growing significantly and with it, so are the implications. To the public, fake science is indistinguishable from legitimate science, which is facing similar accusations itself. Our findings highlight the prevalence of the pseudo-academic conferences, journals and publications and the damage they can and are doing to society.

Quote is video description on youtube video linked above.

The authors generated an abstract using the “Automatic CS Paper Generator” available here: https://pdos.csail.mit.edu/archive/scigen/ which was accepted for presentation at WEAS London. The went along and presented their nonsense paper at WEAS, no one there knew it was nonsense, because non of the people in the conference knew about computer science either, they actually won an award for best presentation.

They used tools to download and analyse authors from predatory journals, many authors are associated with prestigious institutions and companies which might be publishing with an agenda, what’s that all about?

Here predatory journals are defined as those which claim to be peer-reviewed but actually seem to be publishing for a fee instead. Low quality science journals, are they a threat to science and society? Fake news, fake science, what’s that about, do we need to start to think critically about everything we read? Ok, from now on…

Tens of thousands of abstracts were scraped from the OMICS and WASET websites, in terms of author affiliations, India and USA lead. With 15,000 papers submitted from Indian researchers. USA followed close behind with 13,000 papers submitted to OMICS (10,000) and WASET journals (3,000).

Eckert and her colleagues discovered 162 papers submitted to WASET and OMICS journals from Stanford, 153 papers from Yale, 96 from Columbia, and 94 from Harvard in the last decade. Yet according to Krause, “this goes way beyond academia.”

Quote from a Vice article on the story

The authors of scigen originally had their randomly generated paper accepted at WMSCI 2005 (looks like same conference organiser as for WEAS 2017(year?)?). I think they were dis-invited by the organisers after it became known their work was randomly generated. They held their own parallel session in the same hotel and invited WMSCI delegates to attend.

Nitinol Stent

This stuff is like magic, it’s metallurgy.

They call this elastic memory, the mechanical properties of nitinol be controlled by composition and prior treatment. Here the stiffness has been decreased such that it’s much lower than we expect in a metal.

Some background about shape memory effect (Materials Science and Metallurgy Department, Univ. of Cambridge):

Example manufacture of knitted stent:

Football world cup crystal distraction

I was captivated while watching a football match by this nice netting. It’s similar to the crystallography of a single graphite layer. Close inspection shows that the netting doesn’t have perfect hexagonal symmetry, as different sides of the hexagon are made up either two or one rope. Also, sadly the football shown doesn’t obviously have the Buckminster Fullerene type stitching that is sometimes used in footballs, a missed opportunity?

Edit: Image shown is from 2014 World Cup, not the current year.

mtex examples with data

I have been doing a bit of play using mtex to look at some EBSD data which I previous exported to .ctf format. mtex is an open source (GPL) software, which written for the commercial matlab software. The mtex package comes along with several examples and tutorials which can be read within matlab or over the http-internet-web.

Example scripts for using mtex are also available to download from the recently published paper “On Three-Dimensional Misorientation Spaces” by Krakow etal. published in Proceedings of the Royal Society A, 473, 2017.

Scripts and EBSD data for the case studies in the paper are available here:

https://www.repository.cam.ac.uk/handle/1810/263510

Scripts for producing other figures in the paper (explaining orientation relations etc.) are available from the mtex website here (along with other examples):

https://mtex-toolbox.github.io/publications.html

Angel of the North

The Angel of the North: Image from Wikipedia

At 200 tonnes excluding the concrete piles used to support it, the total cost of The Angel Of The North was said to be £800,000. That means the installed cost for the 200,000 kg was £4 / kg.

The Angel Of The North owes it’s appearance to the weathering steel it is constructed from, these steels are designed to form a stable oxide layer, with a low corrosion rate across the entire surface. This strategy means that it’s possible to have a reasonable service lifetime with a minimum of maintenance, even an initial layer of paint is unnecessary.

Example weathering steel compositions / wt%

Grade	C	Si	Mn	P	S	Cr	Cu	V	Ni
ASTM A242	0.12	0.25–0.75	0.20–0.50	0.01–0.20	0.030	0.50–1.25	0.25–0.55		0.65
ASTM A588	0.16	0.30–0.50	0.80–1.25	0.030	0.030	0.40–0.65	0.25–0.40	0.02–0.10	0.40

Somewhat uniquely for steels, the initial rust layer protects the steel underneath from further deterioration, eliminating the need for paint. This depends on environmental conditions, too much humidity too often mean that the rust layer never reaches a stable point. This can lead to corrosion and loss of integrity.