Say you have 1000 pages of content and you want to change the footer or something in the header (suppose Google or Facebook now demand a new meta tag). Do you really want to change all those HTML pages by hand?
Also most web sites have navigation, lots of internal links will help web crawlers find everything and decide that it is important. Are you going to back and change them all by hand whenever you make a change?
The aircraft is able to climb under its own power. We have a diurnal energy cycle - charging the battery up through the day and deploying battery energy in the night. If we launch in the morning with a full battery, we have a whole day's worth of extra solar power to use to climb up to altitude.
Winds will be a bigger issue than energy when climbing. Up at 20 km (70k ft.) winds are quite calm, but we need to ascend through more turbulent winds as we climb. We’re sizing our MVP around this.
Winds up to 20 km are NOT quite calm. They can max out to 60 m/s at height of 10 km, which is more than 3 times than enough to blow a solar aircraft far-far away. You have to choose proper meteo conditions for climbing and descending and plan the trajectory taking into account those winds to be able to land at a given place.
I've been analyzing GFS data a couple of years ago for similar project. The problem is that lack of energy demands to design a really low speed aircraft for low densities that you can find in stratosphere. At 10 km winds are stronger than in stratosphere and density is higer.
You can find the results in https://journals.sagepub.com/eprint/GVXWXDABPE6A8PNRGTBU/ful....
The whole aircraft model probably is not like yours and is subject to many conservative estimates, but I am pretty much sure that wind model is accurate in this publication and generalizable to different regions.
I suppose an aircraft like this can climb like gliders do, using the streams of air that move upwards. This requires some planning, and likely a skilled glider pilot to help choose the course.
I'm similarly curious. Designing for a higher stall speed permits smaller wing area, lower drag, and lower weight. The cost is that takeoffs and landings become troublesome.
Other options that might work:
* Launch from the roof of a vehicle
* With a glider winch
* Towed by another aircraft
* Auxiliary engine / batteries that can be jettisoned & parachuted down
Climbing to altitude is the straightforward part. The transition from zero knots to the stall speed of the aircraft (minimum speed at which it can remain airborne) is the tricky bit. Designing for a lower stall speed necessitates wings which produce higher drag (by being larger) which requires more propulsion, which means bigger batteries and motors. So launching from a catapult or rocket or mothership or whatever means a lighter plane.
Launching by rocket means the plane would have to be pretty rugged to survive it. And that means more weight. You also have the issue of deployment. Folding wings means more weight and more things to go wrong.
Very similar at the entity level, but C#'s LINQ interface to the generate the query is unique as you get fully typed queries in C# that are translated to the underlying DB.
They better be careful. Once the fish get a taste for lion, they may establish a beachhead, and construct a breathing apparatus, perhaps of kelp, to hunt down the remaining members of the pride.
I'm fairly confident posts like these are artificially weighted to fall off the front page..that seems to happen when a COVID related post gets popular on HN. This post has more points and comments than the majority of stuff on the front page but it's currently on page 3.
I've casually noticed something similar over the past ~18 months with posts related to COVID.
Yeah, an opinion I share, and if enough people share that opinion, HN is designed to react.
I'm not going to stop flagging this kind of content, and dang is here to overrule me/others when he feels the need to, which is also how HN is designed.
The post is up, the system is working as intended. We all have roles to play here, no need to worry!
Is “because I think they become too toxic” a good reason to flag a post? I flag spam, shitposts, unsubstantiated or patently false articles. You, like other people, are abusing your flagging powers.
I find it interesting that this story was picked up by the WSJ and has not yet hit the NYTimes. The WSJ editorial staff is well known to have a conservative bias, but their newsroom editors are considered to be quite centrist.
That NYT doesn’t think this story is newsworthy is itself newsworthy.
It’s a WSJ exclusive, negotiated by the journal. You can read that fact in red above the headline. What it gave the deep state in return for the exclusive is unknown
Why? What's the thinking in that decision? This kind of post draws out the lowest quality comments and attracts accounts that comment only on this kind of post.
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