danpat

Network cards are subject to lots of signal phenomena that are rare inside the chassis. Long cables are pretty good antennas for certain types of RF signals, so there are all kinds of electrical noises, induced power spikes and other miscellaneous garbage that the network card has to tolerate. Well-shielded cables can help protect the card, but it's definitely one interface that's subject to a bit more electrical abuse than the rest.

Components that have been stressed beyond their tolerances a few times can result in things like signal filters having a lower noise threshold, which makes it harder for the card to pick out the signal from the noise, which leads to more packet loss. After enough abuse, the threshold drops below the usable level and communications halt.

There are lots of factors involved, such as shielding, proximity to nearby radiators, bend radius in cables, cable length, temperature, etc, etc. Whenever I delve into this world, I'm often amazed that anything works at all.

It's not useful or practical in many situations that we associate with cryptography over the internet, but it certainly has its applications.

Almost every other cryptographic scheme exists in order to increase convenience, at the expense of some security. The one time pad method is "perfectly" secure (assuming the key is securely generated, and kept safe), everything else is less than perfect (although computationally improbable).

The German Passivhaus standard shows what can be done with this approach, and it works very well.

- building codes raising the bar, which has brought down costs for what used to be "fancy" materials

- improvements in building science

- increased energy costs driving demand for improved efficiency

- greater awareness of energy consumption amongst the population

I've renovated a few houses build in the 60's and 70's in Canada. As far as I can tell, they had the materials and knowledge to make far more efficient houses, but much of the time, it was just easier, quicker and cheaper to install a big-ol' heater and drive the cold out. With a few simple and relatively cheap building envelope modifications and a more efficient heat source, it wasn't difficult to bring heating costs down by 50% or more.

I'm mostly using cellular/mobile vehicle trackers (of which there are hundreds of vendors), but for regions where there's no cell/mobile coverage, we fall back to satellite options. With lots of optimization, it's only slightly more expensive for our use-case.

Specifically, we deploy these units:

http://www.skywave.com/en/our-technology/satellite-cellular-...

which use the Inmarsat constellation. The specs probably aren't quite up to being attached directly to an airplane, but with the right housing and a heater, they're probably not far off.

The trick for finding robust off-the-shelf gear is to look for industries that operate in remote regions, like oil and gas, and maritime. They also have fairly harsh operating conditions, so equipment sold there is usually fairly tough.

Prices have really come down over the last 5 years.

What I don't get is why airlines insist on bundling emergency telematics along with position tracking. It massively complicates what otherwise is a pretty simple problem. It feels like that description of the Bradley Fighting Vehicle out of the Pentagon Wars movie.

With a box the size of a Big Mac, at <$1k per unit and about $100/month in data costs, you could deploy an off-the-shelf industrial grade tracking unit that would transmit location/speed/altitude every 10 seconds whenever the unit is powered. All it would need would be a power supply. This would neatly solve the "where the heck is the plane" problem, globally, for a fairly trivial cost.

I realize that finding a spot on the plane to mount it, verifying aerodynamics, figuring out how to wire it in, testing, doing the work across a fleet and managing all that data all end up costing a lot more than the equipment, but given the costs being quoted for some solutions in the articles that have been coming up, it really seems like the airlines could have a big PR win by paying for it with petty cash out of their marketing/advertising budget.

They run the machines over the snow on a daily basis. After a week or so of passes over the same trail, you get a much better idea of where the average line is.

The data my clients typically initially supply me with is usually taken with a single pass using a Garmin unit strapped to the handlebars of an ATV. They often wonder why it differs so much from the results they're getting from the vehicle tracking equipment.

The only other sensor being used is a current sensor, a.k.a a multimeter.

You could make a real ghetto version of this jig with a laser pointer, multimeter and variable power supply.

All the laser pointer does is point at the wall and show you the position of your balance beam.

The LabJack ADC, Phidgets DAC and Photodiode make up nearly $450 of the total cost. An Arduino, breadboard and a few components could probably do the same for a whole lot cheaper.

The concept of "low cost" here is relative to a dedicated lab watt balance machine, which is probably thousands of dollars.

Don't radios with earpieces already do that?

Better off looking for ways to reduce rolling resistance on road surfaces.

As far as I can see, all I would need to do would be show up on polling day, show my Idaho drivers license, fill out the registration form, and vote.

The only proof of US citizenship required is that I would tick a box that says that I'm a US citizen.

I can very easily see that being fraudulently exploited, or just plain misunderstood by new immigrants.

I grew up in Australia, where voting is mandatory and has been for nearly a century. The system seems solid, and there is very rarely talk of vote fraud. The history of voting in the US is so full of change and diversity that I'm hardly surprised there are opportunities for exploits like this.

1) Download the SRTM elevation datasource for the region you're interested:

http://e4ftl01.cr.usgs.gov/SRTM/SRTMUS1.003/2000.02.11/

2) Load the .HGT files into PostGIS using raster2pgsql:

http://postgis.net/docs/using_raster_dataman.html#RT_Raster_...

3) Run your queries, relatively simple:

SELECT ST_Value(elevationraster, Point(51.123,-91.123)) FROM elevation_data;

edit: it's a Monty Python joke people. Perhaps more relevant would be to have a chat with Keith Maniac from Guatemala, who claims he can put bricks to sleep? (ref: http://www.montypython.net/scripts/interest.php)

In many situations, no matter how rational the person, imperfect information can lead to two choices appearing equivalent. How is a perfectly rational being supposed to act at that point? Making a decision based on some kind of tribal affiliation ("Well, these two things seem the same, but this one is how it's been done in the past") might actually be a useful fallback behaviour, as past successful experience might be an insight when all other things seem equal.

It's interesting to note that many of the behavioural patterns that are labelled as "mental illness" often combine "difficulty making decisions" and "lacking emotional response". People who are excessively rational often have trouble functioning in society.

Fundamentally, I believe that those deep seated irrational axioms are necessary for us to function. Without them, we'd freeze and crash at the next logical paradox we came across. Without a little bit of irrationality, how do you decide what to do next? What do you do when you get to the end of the decision tree?

Look, you're right. Used tactfully, by reasonable people, they would absolutely make a fantastic photography platform, and probably not be too intrusive.

However, I have insight to the daily lives of park wardens in popular national parks.

There aren't many of them, they have to cover huge areas, and they spend their days stopping people lighting things on fire, breaking things and taking them away, writing their names on things and trying to put their kids on the backs of the wildlife for photos (I kid you not, it happens once or twice every summer).

I guarantee that if drones were permitted, some people would be buzzing them around the wildlife from a safe distance. This kind of added stress on the animals can and does lead to failure to breed, which has very bad effects on the viability of species, particularly for the less populous apex predators (bears, wolves, big cats).

From the parks point of view, they have to come with policy based on gross population behaviour. They can't supervise or train everyone using the park, so they have to come up with simple policies that can be blanket applied. Unfortunately, the potential for abuse with drones is probably pretty high, thus the ban.

The problem with things in the sky is that they visible (and often audible) from long distances. A single noisy drone might affect several square miles, covering hundreds or thousands of people (depending on the location). A guy hiding behind a tree with a tripod will likely affect a few square yards, and a tiny handful of people.

How frustrating would it be if you couldn't get that nice photo without someone elses drone in it from your flying drone?

I live near the Banff National Park in Canada, and it's a continuous game of tug-of-war for the wardens trying to decide what activities to allow in the park. With no restrictions, the place would quickly be overrun. When the point is to experience the wilderness, you have to be very aware that some activities can very quickly, and with very few people, destroy that experience for everyone.

If you want to work on a new feature that'll take a long time and require several people, grab the code, stick it in git, and work on it with your team. Once the work is done, send a patch to the postfix maintainer, and he'll merge it if it's worthwhile.

Linus created git because the above workflow was killing him trying to handle the patches for the Linux kernel. He was doing it almost exactly as described above for a long time. I suspect postfix sees a far lower volume, and the above workflow probably works just fine.

http://en.wikipedia.org/wiki/Irukandji_syndrome

Choice quotes:

> most cases require intravenous opioid analgesia ...

and

> One unusual symptom associated with the syndrome is a feeling of "impending doom".[13] Patients have been reported as being so certain they are going to die, they beg their doctors to kill them to get it over with.

What sports fitness accessory company? It's a pretty small town, I probably know them....

To do it on a wide scale would require ridiculous amounts of energy. I guarantee that nobody would be prepared to foot the bill for that, and these solar panels are highly unlikely to produce even a tiny fraction of the amount of energy required, unless you amortize their production over a longer period and store it somehow.

Unfortunately, it's not just a "little more costly", it's massively more costly, to the point where it's just not a good idea.

http://www.concretenetwork.com/concrete/snow_melting_systems...

All the other obvious problems aside, it might be an interesting analysis to see if there would be sufficient yearly yield to offset snowmelting operations in winter. Snowfall is not constant, so "melt" operations might only need to run for a handful of days per year, depending on the location.

http://www.reddit.com/r/IAmA/comments/1042mm/solar_roadways_...

The summary seems to be "we've got this awesome idea, and lots of money, now we're going to try to see if it will work."

The engineering consensus seems to be that it won't, or at best, will have extremely limited applications. Everybody would be far better off putting high-efficiency solar panels on rooftops than low-efficiency ones on the ground where they'll get dirty and broken.

Reading their literature, there seems to be a great big gap where any kind of decent engineering analysis would be.

While I can see the appeal of the idea, unicorns and hyperspace drives would also be pretty cool. I have my doubts.