chris_va

17 ms·

211.
by chris_va 5y ago
Generally ATC will switch to English when an English speaker comes onto the frequency, but local language is fine otherwise... country dependent, though. I haven't flow in France, but I understand it's mostly in French until someo
212.
by chris_va 5y ago
Takeoff and landing distances are based on surface conditions, and those conditions have to be known for pilots to make accurate decisions for the type of aircraft they are flying. Presumably unexpected water on the runway (which might late
213.
by chris_va 5y ago
Bunnies can keep the grass quite short.
214.
by chris_va 5y ago
Copy editors generally write the headlines, and reporters write the body. ... probably one of the worst industry practices of all time.
215.
by chris_va 5y ago
not quite the same, maybe "early plumbers"?
216.
by chris_va 5y ago
Having peeked behind the political shroud on occasion (and still by no means an expert), I think people overestimate the complexity of the US political system. Most politicians are not imposing some personal beliefs, they are just represent
217.
by chris_va 5y ago
The "risk from getting an infection" includes many other side effects besides myocarditis, I would not evaluate the risks from an unvaccinated viral infection (which can cause 100 other things besides myocarditis) vs the risk from
218.
by chris_va 5y ago
The estimate is about 20x smaller
219.
by chris_va 5y ago
It is really fun to imagine :). I am imaging the horrors of an HP printer ecosystem on a farm... Which now makes me wonder why HP printers do not require special HP paper. Fortunately, there is not much moat here. If John Deere demonstrates
220.
by chris_va 5y ago
Seems unlikely. Not that it could not happen... there are various hedge funds that do this already, with mixed success. They generally lease back to a farmer. John Deere doesn't have any data that the farmer wouldn't have, and the
221.
by chris_va 5y ago
The technical ramp up/down issue is often conflated with amortized capital cost. Nuclear, in order to provide electricity at a competitive rate, needs >90% capacity factor. That means it can't ramp up/down and stay in busi
222.
by chris_va 5y ago
To be fair, residential/commercial heating could be entirely electric, and heat pumps have additional benefits over natural gas heating (like being reversible in the summer). Presumably people would switch if the cost of electricity wa
223.
by chris_va 5y ago
FWIW, depending on the satellite (this one is probably WorldView 3), there usually more like ~6-7 channels in the visible. It makes for easier top-of-atmosphere correction, and can be useful for things other than pretty pictures.
224.
by chris_va 5y ago
NREL has some decent material on LCOE calculations. Amortized capital cost would be a function of upfront cost, lifetime (years), cycles (and per cycle efficiency over time), capacity factor (e.g. average drawdown of the batteries per cycle
225.
by chris_va 5y ago
Curtailed renewables might make this economical in the short term, but also provides the same benefit for competitive storage technologies (e.g. LiFePO4 batteries). You'd have to compare the LCOE for each over the lifetime of the insta
226.
by chris_va 5y ago
(I do some research in this space) There are lots of cheap ways of storing heat... The capacity cost of thermal storage has not been the bottleneck for commercialization, but rather the round trip efficiency. This seems academically interes
227.
by chris_va 5y ago
Emissions are not always persistent (esp with methane). There is a lot of work done to try and reverse advect plumes using tropospheric wind data... But it's not an easy problem
228.
by chris_va 5y ago
(disclaimer: I work in a climate&energy R&D lab) > since hydropower production emits no greenhouse gas emissions. ... that is incorrect. Hydro reservoirs emit a fair bit of CO2 and CH4, especially cold northern lakes with large s
229.
by chris_va 5y ago
Way better than my rate at bfi, which fbo?
230.
by chris_va 5y ago
Drilling cost is usually estimated as ~depth^2. So, a 1km geothermal well? Break even, and you are limited to only a few places in the world. A 5km geothermal well (needed for broad power availability)? 25x the cost... So, sure, if you can
231.
by chris_va 5y ago
... The concept of a car company purchasing a flailing solar company that happened to be owned by the same individual is probably worth of some eyebrow raising. So, I am not sure "manufactured" is the right term here, regardless o
232.
by chris_va 5y ago
Rather than use a depth map, it might be more robust (though probably a bit more expensive) to just use a beam splitter (dielectric, at the laser wavelength) and have the camera share the bore-sight with the laser.
233.
by chris_va 5y ago
I read that paper the opposite way. 32% being repurposed seems like a pretty high number. I cannot reconcile these articles with the high investment in repurposing I see in pharmaceutical startups.
234.
by chris_va 5y ago
I am not sure why this is written as if drug repurposing is an under-explored concept. Repurposing generics has becoming increasingly popular, because the clinical trial risk is much better in phase 2/3 (where most of the money is lost
235.
by chris_va 5y ago
Thanks, more or less the reality check I was hoping for :)
236.
by chris_va 5y ago
Seems like one could design the tread (or an extra rubber tab) to catch the wind and self spin.
237.
by chris_va 5y ago
If I am reading the document history right, the title should probably should read: "[2013] Status of Previously Proposed Coal Plants" ... no one is really building much coal anymore in the US, renewables have made the daily market
238.
by chris_va 5y ago
Just responding to this statement: > I don't see why climate change would affect the positive aspects of fire. ... since it has a strong effect on the fire and the forest, both pre and post fire. It changes a lot of calculus, includ
239.
by chris_va 5y ago
Climate change brings invasive species, so fire behavior can be very different (and regrowth post-fire can be very different).
240.
by chris_va 5y ago
(disclaimer, I work in a Climate&Energy group) - There are a number of technical solutions for climate change. - There are a number of technical entrepreneurs who would love to implement those solutions. ... there is no market to pay fo

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