Re: Face shields on various scenarios (Another thread)

I was asked, in the spirit of the RCTs, whether I have explored the other scenarios concerning face shields.

Well, yes, I did.
The intervention of face shields against sporadic emissions at different angles of attack was simulated and observed, and as it turned out that the ballistic protection only applies for emissions coming from the front. From other angles, risk increases:

The speed of cough simulated was 50 mph. Here, it was illustrated how the momentum of the emission decreases over distance, while also noting the advection also:

Face shields became a liability at situations when people are falling in line and someone coughs from behind (angle of approach from the back). The face shield redirects the emission to the face:

In contrast to the natural scenario of not having face shields where most of the jet of the emission will just veer away:
For non-sporadic emissions and scenarios where the aerosols are just lingering in the air or was being carried by the air flow, the other angles of attack are considered. For example, with air flowing from the side, which is already obvious:
When people look left and right (probably shopping) while in motion and while also wearing a face shield, with the flow coming from an oblique angle, the negative pressures are more stable and stronger, sucking in more airborne particles:
Of course, the control setup was also simulated. The scenario where the person is not wearing face shields:
If curious how the simulation was done, here was the documentation of the preprocessing stage:
All of the simulations were unsteady state CFD analyses, with LES (Filtered TKE model by You and Moin (2007) as the turbulence model. The Courant number across the whole domain of all the simulation were maintained to be less than 1, to ensure stability and proper resolution.

• • •

Missing some Tweet in this thread? You can try to force a refresh

Keep Current with Joshua C. Agar

Joshua C. Agar Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!


Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @JoshuaCAgar

12 Oct
And as it turns out, the initiative of exploring the potential for wind power that led to the wind farms in Ilocos Norte...

...came from USAID!

The Marcoses have been consistent of grabbing credit from USAID!

Documentation of the Initiative:…
The study of compiling the atlas for wind energy in the Philippines started in 1996. The atlas was finished at 2000:

(Lol. They indeed did GEV analysis and interpolated using the projected wind exposure parameters)
Bangui and Burgos became the ideal locations. Northwind invested on Bangui and First Gen invested on Burgos.
Read 4 tweets
12 Oct
Misinformation and falsehoods cascade across three layers:
First is with the perpetrators who spread disorienting misinformation in social media.

Second is with the media on which some are disoriented and pass on the disorientation to the masses.

Third is with the masses.
Indeed, the battleground may be dealing with the source. But the ripples of misinformation still trickled down to its main interest and intended audience: the masses.
Given that the surveys determined that mainstream media are still the main source of information of people, we look at media personalities who package their commentaries, which contained their personal biases, as if those were the news.
Read 6 tweets
11 Oct
Debacle of face shields in the Philippines

(A thread)

I see that some of the scientists from other countries are considering recommending face shields to be worn in public.

I beg to differ, presenting how face shields represented the poorest pandemic response in the world.
December 11, 2020

The Inter-Agency Task Force (IATF) against Covid-19 of the Philippine Government, through its Resolution no.88, mandated the use of face shields even in public, outside of hospital settings.….
The technical advisory body of the IATF, spearhead by infectious disease experts Dr. Anna Lisa Ong-Lim and Dr. Edsel Salvana claimed that a randomized control trials (RCT) conducted in the public hospitals and another performed in India reported 90% efficacy rate.
Read 31 tweets
10 Oct
Taytay Chronicles w/ Bayaw Erik
(October 10, 2021)
The dreaded face shield
How to assemble and "use" face shields
Read 12 tweets
10 Oct
Kindly ask those "lolo" and "lola" giving anecdotes that "attest" the Marcos regime the year-by-year state of affairs during that period. Ask them the specifics, what specifically happened in '72, '77, '81, '83, 84', and '86.

That's how historiography establishes veracity.
If they can't provide any to establish the veracity of their narrative, then that points of view that they are presenting, like the other dramatis personae in the past making good light of themselves, will be rebuked, shunned, and reprimanded.
You could also ask your lolos and lolas about their knowledge of how government works, the separation of powers, their knowledge of the constitution.
Read 5 tweets
9 Oct
For the sustained wind criteria in the placement of turbines, one can perform wind spectrum analysis (accurate but hard to interpolate and gather) or generalized extreme value analysis (up to the daily maxima).

Here is the GEV analysis of the weather stations across PH: Image
μ represents the base wind speed, which is the expected annual maximum. σ and ζ represents the steepness ("slope") of the extreme value function. The steeper the extreme value function, the higher the difference between annual max from historical max.
The goal in selecting optimal locations for wind turbines is to have a significant μ, but a lesser σ. However, even after this analysis, one must still project the wind spectra by the evaluation of the wind exposure, which is related to the topography and atmospheric boundaries.
Read 5 tweets

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!

Follow Us on Twitter!