Joshua C. Agar Profile picture
Sep 6, 2021 5 tweets 2 min read Read on X
Sideview and the Topview of the previous case shown earlier of a person wearing a face shield.

Evident in the top view of the velocity field, vortices and reverse flows, typically present behind the head are now present in the face due to the intervention of face shields.
No face shield scenario:
[Close-up; Top View] With Face Shield Scenario

Due to the negative pressure due to the massive change in momentum caused by the face shield, flow reversal happens where the wind flow (along with the suspended particles) is redirected to the space bet. the face & the face shield.
The differing angles of attacks are also considered. Below is the simulation results of a cough coming from an angle of 45 degrees wrt to the front of the person not wearing a face shield. Evidently, the accumulation and deposition happened in the leeward side.
With Face Shield

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More from @JoshuaCAgar

Feb 28
I tried to start my class w/ a classroom chat, asking their reactions on the current events.

Students told me that they were not keeping tabs on the current events, as they were drained w/ their academic load.

There has to be an energy to spare if one wants people to care.
As I commute home one night, via the EDSA Carousel Bus, I had a long walk and a long climb to get on the bus.

Some people who boarded the bus at the same time, the moment when they sat, fixate themselves on the Reels on Soc Med, with some coming from the fake news purveyors.
Parents, tired at work, come home to only encounter their children question their political choices at the family table. As they have no longer the energy to spare to even engage in political discussion and welcome the prospect of them being wrong, they will shut it off.
Read 7 tweets
Feb 26
The sense of elitism prevents us into looking deeper as to why most Filipino citizens make questionable choices at the ballot box.

Empathy requires us to understand that they are also overwhelmed by everything and as a result, tend to conserve their energy.
Reading posts such as this requires energy.

Processing the message requires energy.

Inquiring past the comfort zone requires energy.

Learning about all the candidates requires energy.

Combating the cognitive dissonance due to conditioning infos shoved on them requires energy.
But...

Working for make a living requires tremendous energy.

A hellish commute drains energy.

People require energy to get out of their comfort zones.

People require energy to make realizations and pull off rectifications.
Read 13 tweets
Nov 14, 2024
I advise people to subscribe to vital weather information from weather agencies and reputable scientists with their reputations at hand, since accountability forges trust.

I also would want to you to sit through and read through this thread that gives complementary information🧵 Image
It is also important to anticipate and know where the winds will be coming from due to what's called wind exposure affecting the characteristics of typhoon winds, on how strong and/or consistent they will be depending on your location. Image
Winds at sea will experience little to no dissipative effects. Therefore the winds will be consistently strong.

The peak gust (bugso) will not be far on how strong the sustained winds will be. Image
Read 30 tweets
Dec 21, 2023
Our study that developed CO2 monitors that informed occupants of the relative risk that they may be subjected to due to airborne diseases transmitted through shared room air transmission has been published. #CovidIsAirborne

doi.org/10.3389/fbuil.…
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Using a multivariate method, the ventilation rates of different indoor spaces are determined and used for the subsequent computations using the Wells–Riley model to derive the respective infection risk, particularly of COVID-19. Image
"Infection risks are determined to be higher in indoor spaces with low ventilation rates. However, having high ventilation rates does not mean low infection risks as smaller spaces will also have higher infection risks."
Image
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Read 7 tweets
Dec 12, 2023
Part of the PowerPoint presentation to be presented on Thursday:

How aerosols move Image
Conservation of Mass
Image
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Infection risk modeling

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Read 4 tweets
Apr 23, 2023
High humidity also attributes to high infection rates and deaths due to Covid-19.

Shown below are the trends derived from the correlation between Covid-19 deaths and relative humidity. 60% RH is the Goldilocks Zone: lesser or greater than that results in the increase of the risk Image


Why 60%?

It has to do with two things: (1) lessening evaporation rates due to inhomogeneous mixing and (2) rate of condensation which attributes to the increase of pore pressure within the mask.royalsocietypublishing.org/doi/10.1098/rs…
Countries above the tropics experience case surges during their winter season when relative humidity is low. The hot and humid respiratory emissions will mix with the cold and dry indoor air resulting in higher evaporation rates,
Read 7 tweets

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