Recently the Haze in Singapore is getting worse. One can literally smell the burning smell in the air.
A recommended cheap and good air purifier for home usage is the Xiaomi Air purifier. Xiaomi is well-known for producing high-tech goods at affordable prices. For instance, their weighing scale and fitness band (Mi Band) is top-notch for their price range.
Recently, Singapore is plagued by the haze, arising from forest fires in Indonesia. This is a common occurrence that happens yearly.
Simultaneously, I noticed a drop in Wifi speed both at home and at work.
Is this a coincidence? Or could the haze particles be actually blocking/absorbing Wifi signals so that the Wifi is slowed down?
What do you think? Probably the same effect occurs for smog or fog.
It is well-known and established that rain affects Wifi. Hence, perhaps it is not too far-fetched to postulate that the haze affects Wifi too?
Recently, the Singapore Haze is getting quite bad, crossing the 200 PSI Mark on several occasions. Do consider purchasing a Air Purifier, or some N95 Masks, as the haze problem is probably staying for at least a month. Personally, I use Nasal Irrigation (Neilmed Sinus Rinse), which has tremendously helped my nose during this haze period. It can help clear out dust and mucus trapped in the nose.
Previously, we proved that any subgroup of index 2 is normal. It turns out that there is a generalisation of this theorem. Let be the smallest prime divisor of a group . Then, any subgroup of index is normal in .
Proof: Let be a subgroup of of index . Let act on the left cosets of by left multiplication: , .
This group action induces a group homomorphism .
Let . If , then for all . In particular when g=1, xH=H, i.e. .
Thus . In particular, , since is a normal subgroup of .
We have . Thus .
Also note that . Note that since .
Let be a prime divisor of . Then since . Also, . Since is the smallest prime divisor of , . Therefore, , i.e. .
Then , i.e. H=K. Thus, H is normal in G.
Is the Singapore Haze coming back?
The haze is clearly coming back in Singapore, as haze hangs over Singapore on Sunday evening.
Interested how PSI is calculated using Math? Check out this article on The Math of air pollution at: http://www.intmath.com/blog/math-of-air-pollution/8170