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Comment Re:Not a safety hazard? My ass! (Score 1) 96

Most of Australia's controlled airspace uses ADS-B for separation. Only the densely populated areas have secondary radar.

The risk of a collision is relatively low as they most commonly separate by altitude and a 70km horizontal deviation probably wouldn't reach another flight path.

It does screw up separation monitoring and safety management programs fairly badly though. Some plans also have ADS-B based collision alert systems too, which would cause lots of panic if they went off.

I am blown away that the 787s cockpit network is so bad that it routinely drops position data packets. Often enough that it frequently loses multiple sequential packets and the firmware developers implemented a dead reckoning system to plaster over the issue. How do you screw up a network that badly?

Comment Been running at Alice Springs for a while (Score 1) 104

Alice Springs in Australia has been testing this system for a few years. Unfortunately I'm not sure how it worked out as I am no longer working in the field.

The Alice airport has an interesting problem. Basically there aren't a lot of flights and in a normal situation the airport would not have tower controllers. However the flights that are there tend to come in dense waves, so the risk is higher than the average numbers would indicate and they had to have a controller. I also believe that they lost money on the airport because fees are charged per plane that lands.

The hope of the remote system is that they could have a team on staff for the few hours a day that control was required and the rest of the time the airport would run uncontrolled and the staff could be utilised elsewhere.

Comment Re:An immediate opportunity (Score 1) 17

It is an interesting problem but as you get into the details it rapidly becomes more complex.

  1. You need to detect the difference between a normal movement such as walking or kneeling and a fall. This is complex because we move by deliberately off balancing ourselves. This also has to be highly accurate, a 1% false positive rate would make walking around impossible.
  2. The person has to be saved from the fall. It isn't enough to straighten the legs, in fact that could make it worse. The whole body has to be righted, with assistance because the core muscles are probably also weak.
  3. As outlined in the original post, the righting will probably be performed by shifting out a counterbalancing mass. This mass has to be carried around and probably needs to be around 15-20% of the person's body weight. They obviously won't be able to carry this so assistance needs to be provided

Exoskeleton suits are awesome and I want one when I am old but often the simple solutions like a walking frame or stick are actually the best ones.

Comment Only solving half the cost issue (Score 2) 63

Part of the problem that isn't addressed in the summary is that to have a cm accurate position you also need to have an oscillator that is accurate in the tens of picoseconds range.

From the article:
> The clock attached to the external front-end was an oven-controlled crystal oscillator (OCXO), which has much greater stability than the low-cost oscillators used to drive GNSS signal sampling within smartphones.

An OCXO is far more expensive than a smartphone manufacturer will happily absorb (~$30). It is also constantly heating the crystal so your battery life gets thrown out the window too.

GPS manufacturers very carefully select their cheaper TCXO chips in order to get nanosecond accuracy. Special tricks are used to get sufficient DAC resolution on the voltage control in order to steer them to the correct level. I have been out of the industry for several years but I would be shocked if there has been a 100x improvement in quality without hearing anything about it.

Comment Re: Tabs vs Spaces (Score 2) 428

Which only matters if all indentation, including alignment, is done with tabs. The moment you throw in a few spaces to line something up on a non-tab boundary (say, to align a second line of arguments with the first argument), then you have a mess, unless your tab width is set to exactly the value that whoever touched the code before you set it to.

And here is what you are doing wrong. Tabs are for indentation, spaces are for alignment.

If you are increasing the nesting depth, use one tab.
If you want to shift the start of a line over to align the arguments, use spaces.

Tabs are not X-spaces. Tabs are an abstract indentation level which can be represented as a number of space characters.

Comment Ubiquiti has form (Score 1) 225

As the article said "the company has a dark history of securities fraud, violation of U.S. sanctions, trademark and copyright lawsuits and software patents".

I personally discovered that their standard wifi board didn't follow the mini-pcie spec on flight mode (W_DISABLE). In fact there is no way, other than cutting power to the card, of disabling radio transmissions. Multiple inquiries on this topic were all met with stunned silence. At the time I was working for a substantial company buying boxes of cards at a time, I can't imagine their response to individuals raising issues would be better.

I wouldn't trust a Ubiquiti device in the future, their attitude to standards and specifications could best be described as flexible. As a manufacturer once you incorporate their device into your product you become liable for all their RF creativity, not something any rational company should accept.

Comment Re:I have experienced this first hand (Score 5, Insightful) 574

The catch here is that a degree is a very poor first step.

If you have recently graduated think of the worst person you just went through university with. The one who plagerised all their assignments and never seemed to get caught, who struggles to understand the difference between a loop and an if block, the person you would fake a heart attack to avoid getting stuck with in a group project.

This person has the same qualifications as you do.

In fact, the person described probably has better qualifications on their CV because they are more happy to lie about them.

You need to figure out how you differentiate yourself from them. As someone hiring that person is the absolute last thing I want to end up with and I will happily chuck 50 maybe CVs to avoid them.

This differentiation is where things like prior work experience, open source contributions and memberships of local user groups plays a role.

Btw, being in Aus have you signed up for linux.conf.au yet? lots of recruitment happens in forums like this.

Comment Re:This is complete crap!!! (Score 1) 112

If they're worried about hacking it, it's a complete farce; there's no reason why the computer doing the sums even has to be connected to the internet, seeing as I think all the ballots are counted by people (they're farcically large ballots often described as table cloths), they just plod in a few numbers as the data comes in. Someone must be worried that competent, impartial people will have a look and find something which has been giving out porky pies.

They said "hacking or manipulation", they mean that there are potentially bugs which could be triggered by malicious input. The computer doing the tally is not connected to the internet. This is a bit alarmist and they have only tried playing the card recently, the AEC seems to be getting desperate.

The real reason is the other one that they offered, "underpins the industrial and fee-for-service election counting systems". The AEC makes a fair bit of money running elections private organisations and other countries. While what they primarily offer is impartiality, technical assistance is a strong component and they obviously feel that releasing their software would impact that business.

The AEC tallies have been independently verified several times, there isn't a substantial case that the election outcomes are being distorted. However I still believe that the code should be public.

Comment Changes but not automation (Score 4, Insightful) 870

I live in a country where the minimum wage is roughly $15USD. More crucially though, I live in an area with low unemployment so the practical minimum wage is considerably higher.

What we have seen is changes like such as smaller retailers only have a single staff member on during the week. This means that when the staff member goes to the bathroom or gets lunch, the shop closes briefly. For larger retailers there is an ongoing shift towards self-checkouts, but as they are constantly pushing their costs this seems independent of wage levels.

Other fields have seen similar pressure. Restaurants try and make do with less staff, warehouses focus more on minimising idle time and companies may consider how often they really need the bins empty.

All of these are fundamentally positive changes.

Comment Re: And we're going to trust self driving cars now (Score 1) 664

I've known a lot of high-quality developers over my 15 years of professionally developing software. The reason I don't want an automated car is because of these people. People make mistakes, intentionally or otherwise.

When it comes to true high-rel software, like that written to DO-178B Level A (an avionics software standard used for things like fly-by-wire) it's almost never the software per se that's at fault. The stuff is amazingly good. It's also amazingly expensive to write and test. You might also find it frustrating because it brings new meaning to the idea of conservative design. For example, I don't think it allows recursion. I know it doesn't allow dynamic allocation.

Firmware engineer here. While I don't work on safety critical systems not allowing recursion or dynamic allocation is just standard practice.

Memory leak errors are almost impossible to debug on a microcontroller. So as a preventative measure, standard practice is not to do any dynamic allocation after hitting the main loop. Initialisation is ok, it runs once and never gets freed. Once the system is running however, the risks outweigh the benefits.

Recursion is much the same, it's easy to blow the stack, messy to debug and makes static analysis hard.

While both can be done safely we consider them automatic red flags and any use needs to be accompanied with a justification in the comments. The code is also very carefully checked. Typically the problem is readdressed and another method used.

Comment Re:welcome to the socialist wonderland (Score 1) 206

You are using Australian figures from 2008, which is fair, the income doesn't change too quickly. However the USD numbers are also on 2008 exchange rates, which makes your figures useless.

The 2008 number you quoted (which looks a little fishy), at current exchange rates is $63k USD.

The latest official figures are from 2011 with a median of $64kAUD, the equivilent of $61k USD.

The US census figures list $51k USD for 2011.

So you are right, it's nowhere near more than double. But using decent figures the Australian Median Household Income is 20% higher (2011).

And speaking personally, 20% extra income is a price I happily pay to live in a statist utopia.

Comment Re:Why is EC more secure than RSA? (Score 5, Interesting) 366

The elliptic-curve algorithm is much slower for future quantum based attacks. So it's future-proofing, which is required if you want your secrets to stay secret.

You could get similar results by adopting a 15000 bit RSA key... but that's getting rather large.

A paper with some classical and quantum time estimates, Elliptic-Curve vs RSA: http://arxiv.org/pdf/quant-ph/0301141v2.pdf

Comment Re:When you don't want a reference (Score 1) 892

In Australia I am required by law to give a notice period to my employer and my employer is required by law to pay me for my notice period.

If you read the fine print the punishment for not giving two weeks notice is that they don't pay you the two weeks that you don't work... which seems fair.

Comment Re:You have consented to large government (Score 1) 104

Australia kind of leapfrogged past the US and even the UK in terms of a soft tyrannical take over. I found it surprising, but as soon as they lost their ability to fight (gave up the guns) the changes have been moving very quickly.

You are making a mistake in assuming the Australian culture is the same as US culture. It's one our own commentators have actually started doing too.

Australia has never had the same views on freedom and rights that the US has. It has always been understood that there is a compromise between personal freedoms and state control. An example of this is that we don't have a Bill or Rights, we don't have a Freedom of Expression, in fact there are no "rights" in our federal law at all. (We are a signatory to the UN human rights convention and one of the territories has rights legistlation which complicates things a little, but in general when an Australian mentions their rights they have no idea what they are talking about).

So this isn't a recent tyrannical takeover and raising guns as an issue is completely irrelevant. Hell, we started has a prison colony where everyone had to obey orders and there has never ever been a serious movement of Australians employing violence against their own government. What we have is a misstep by a government regulator that has very little idea what it's doing. The IT press are whipping up the rage to try and ensure that this is an election issue, for at least a day or two. The major parties will probably move strongly to avoid it becoming a problem for them and the regulator will be put back in it's box for a few years.

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