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Posted by cmdl | Aug 30, 2020 @ 09:23 PM | 6,111 Views
The CDC lists 7 chronic, non communicable diseases as the leading cause of death in the country. I estimate that virtually all of the US population will have at least one chronic disease by 2050.

While such diseases account for 71% of global deaths, the number of deaths relative to total global population remains steady at 0.5% - only 1 in 200 people die from them.
Posted by cmdl | May 18, 2020 @ 04:03 PM | 5,409 Views
Independent analysis, using Wikipedia data, corroborates Huebner's observation that technological growth has been in decline for about a century.

PS - Also noted by Tyler and Southwood.
Posted by cmdl | Apr 19, 2020 @ 06:32 PM | 4,705 Views
Mortality/capita over various pandemics range from the Bubonic Plague (about half the population died) to Covid-19 (about 1 in 50,000 people died) with most pandemics showing a negligible impact on total population. More so with pandemics since the last 400 years.
Posted by cmdl | Apr 06, 2020 @ 11:28 AM | 7,249 Views
Using data from 117 countries, population and IQ have an almost perfect inverse relation as seen in the correlation coefficient.
The rate of population increase is irrelevant, any increase is sufficient.

Regardless of the cause, as long as population continues to increase, IQ will decrease.
Posted by cmdl | Dec 20, 2019 @ 05:14 PM | 5,507 Views
Source: https://archive.epa.gov/climatechang...sics/past.html

Step 1: Eyeballing (or use ruler) temperature change with respect to CO2 on the left two graphs (upper is CO2, lower is temperature). Total temp change (F) divided by Total CO2 change (ppm) = Rate of change of temp w.r.t. CO2.
Calculate the rate for the two left graphs (before industrialization) and the two right graphs (after industrialization).

Step 2: Compare the rates.
For the left graphs (before industrialization), I got rate of change = (-15 F to 5F) / (175ppm to 300ppm) = 20 F / 125 ppm = 0.16 F/ppm.
For the right graphs (after industrialization), I got rate of change = (-1 F to 1.5F) / (300ppm to 400ppm) = 2.5 F / 100 ppm = 0.025 F/ppm.

The rate of change of temperature w.r.t CO2 before industrialization is 0.16/0.025 = 6.4 times greater than after industrialization.
Posted by cmdl | Feb 10, 2016 @ 10:35 AM | 12,452 Views
Motor/ESC/Prop/Servos

Pitch speed

Current increase with voltage increase

Extending lipo<->ESC wires

Keeping same pitch to convert between different bladed props
Keeping same load factor (using diameter squared gives more conservative estimate) to convert between different bladed props

Motor attributes
Prop attributes

JST connectors

95% travel adjust on micro servos

Motor wire gauge 1
Motor wire gauge 2

Servo wire gauge 1
Servo wire gauge 2

Lipos

Store in fridge 1
Store in fridge 2

Do not store long term fully charged (cell thermal runaway is unlikely to occur in a cell at a low SOC, < 50%) 1
Do not store long term fully charged (cell thermal runaway is unlikely to occur in a cell at a low SOC, < 50%) 2
Do not store long term fully charged (cell thermal runaway is unlikely to occur in a cell at a low SOC, < 50%) 3

Charge to 4.15 V/cell 1
Charge to 4.15 V/cell 2
Although optimal charge level is 3.92 V/cell

New lipo break-in

Capacity vs voltage 1
Capacity vs voltage 2

Performance tool
Supporting database for performance tool

Balance plug wiring

No negative impact from charging @ 2C, 3C

Paraboards and harnesses

IR 1
IR 2

Low temperature treatment 1
Low temperature treatment 2

Flight

Always check CG

Watts/lb
Static thrust

Read till post #30 - interaction of throttle & elevator

Wind affects aerodynamics 1
Wind affects aerodynamics 2

1s plane BL conversions

UMX B-25

UM P-51

Using X-Port on AR6400

AR6400 manual

XP-7A manual

Main thread

Current draw data

2s to power 1s brick

Don't use the Nano CP X BL

2s Spitfire

Glue

https://www.rcgroups.com/forums/show...2&postcount=11