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Comment Re:Interesting subject, lousy article (Score 2) 103

I agree. The author comes across like a Mean Girls reporter for a high school gossip column sent to do a report on the AV club.

The author's personal biases are palpable as is her fixation on people's bodily functions.

All of the competitors—and this will come as a shock—are men, or at least on their way to becoming men

What's that supposed to mean? The article seems to focus on the author's opinion that the contestants are unfuckable despite them having good job prospects. Did we learn anything about technique or team strategy in these competitions? Did the author care?

Comment Re:Fly or stand by? (Score 4, Informative) 39

Find more details here The planes used a Linux based autopilot to control the aircraft which had waypoints sent to it via onboard Odroid SBCs. Primary communication to and from the planes used UDP packets sent through USB WiFi adaptors hung off the Odroids

2 people "operated" the swarm, one commanding, the other monitoring. Planes got their swarm "slot" assignments at launch and tried to maintain position relative to a lead aircraft once they had reached their slot altitude. It's an interesting read. A quick estimate suggests they put around $1k in hardware into each plane. They describe guiding planes manually via spotter pilots using a secondary 900MHz spread spectrum radio link when anything went wrong.

All planes were programmed with the same landing point, with the assumption that GPS and barometer inaccuracy would provide sufficient spread on landing. But with nearly 50 planes on the runway, on-deck collisions were unavoidable. Some of the video captured by GoPro cameras mounted to the nose of each plane show skidding into other planes, or coming down directly on top of other planes on the ground. Lesson learned for next time: add a bit more variation to the landing coordinates.

Comment Re:FCC's trying to break improving router firmware (Score 1) 345

It's not really about power output on home/office AP's. The problem primarily comes from idiots broadcasting in the unlicensed 5Ghz band using a high gain antenna with a direct view of a nearby TDWR site and turning off or not using Dynamic Frequency Selection (DFS). None of the documented interference cases involved home users turning their WiFi router power up to 11 or selecting improper channels.

I stumbled on this informative report which details the FCC's issues with 5GHz band interference. See page 3-4 for details on the interference problems.

I learned a lot about frequency sharing from this technical report. It's well worth a read.

Comment Re:Weather forecasting has a way to go (Score 1) 43

I can understand why they get predictions about the future wrong, that bit is hard. What gets me is when the prediction for right now is at odds with what is actually happening. It seems like there is a significant delay between sensors on the ground taking a reading and the models being updated.

Most regional models are run at least once an hour and make use of data from sensors up to a few minutes before the model is run. Even if a weather model was perfect, it would still produce incorrect results because models are always started with conditions that do not reflect the true state of the atmosphere. Weather models use other models or earlier runs to produce a best guess at the current state of the atmosphere. The atmosphere model is "adjusted" using the latest sensor, sounding, radar and satellite, data and then the model is run to predict the future. All weather models have to deal with the fact they only have an loose estimate of the state of each 3-D cell in the real atmosphere.

While we have lots of sensors close to the ground, we have very few up high in the atmosphere. The state of the upper atmosphere is rarely measured directly. Balloon soundings are done once or twice a day and only from a few places. The latest soundings have a huge effect on weather model results, so major corrections take about 12 hours if the sounding for an area was not representative of the local state of the atmosphere.

Apart from it being slightly comical when the guy on TV says sun is out but looking through the window I can see rain, it makes short term predictions useless. If they say it will rain this evening when I want to go out but the forecast for right now is wrong, what am I supposed to do with that information?

The best weather models usually get the features right, but are often off in timing. Frontal passages often happen hours from when they are predicted, but they do occur. Use radar and surface sensor data if you want to know current weather. Satellite data are usually less than 30 minutes old. Use model data to get a best guess on the future.

At best you get a vague prediction of the weather in the next few days, but the exact timing of events tends to vary quite a bit from what they say. It doesn't help that in the UK TV weather forecasts are delivered in the most confusing way possible, but fortunately we have the internet now.

Wide spread rain and snow events are the hardest to model or predict as the precipitation falls out in bands which form chaotically. Unless one precisely knows the starting position, one cannot predict the outcome over time. We will never have sensors every N meters in a 3-D grid over the earth so weather predictions will always be off.

Comment Re:old (Score 1) 158

Their just old.

[... whine... whaaa ... ]

There is no solution, there is no fix or magic arrow, and all the bitching of the world won't make them die any faster.

Maybe, instead of focusing all your adolescent angst on your elders, take the time to attend public meetings and vote.
Yeah, we know; you're too busy to do that. Please, stay focused on your little screen while we change the world.

Comment Re:Github is scary for critical code (Score 3, Insightful) 116

This is a good example of people having a fundamental lack of knowledge about Git and GitHub.

You heard; "We don't need a backup because GitHub is so awesome". That does sound scary.

However, the whole point of Git is everyone who cares about the project has the complete repository, usually with multiple backups, and works "off-line" as normal practice.

Github is just an awesome and easy place to share a copy of the repository. It's trivial to set up another shared repository or just share directly with those involved in the development.

Comment Re:I love the alert they changed the page to (Score 1) 116

This was the whole point. Someone wanted to cause a disruption to users in China surfing via a VPN.

I assumed they selected Github as the target because they wanted an effective response delivered to the originators of the original http request.

They are constantly mapping accessible VPNs and developing countermeasures against them. I understand it's a constant game of whack-a-mole over there with access to VPNs outside the great firewall.

You are in a maze of UUCP connections, all alike.