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Comment Something not technical (Score 1) 238

if the boy is so incredibly technically oriented, he probably lacks in his social areas and artistic sides. Rather than pushing him more into his math-freak corner, which he would probably reach without much help, I would give him something that would help him play with other kids, rather than a computer. Something like a football, a skateboard, a guitar or mini-keyboard (music and math have a lot in common), or a kids bike.

I am by no means implying that this is the case with your nephew, but I find it amazing how often people miss the balance in life, and end up pushing kids into a niche corner.

Comment Women's reaction to protential a price drop (Score 5, Insightful) 119

Women always want diamonds because they are "beautiful". If their price drops to the floor, I wonder whether they will still like them on their wedding rings. Truth is, most women don't care about what they wear, as long as they have the feeling that you bought them something special. And if their friends envy them, then it's even better.

Comment Strange numbers and interpretation (Score 1) 145

I have lived in Shenyang for about two years.

I don't get this whole metric anymore, and the numbers seems to be either wrong or being manipulated, as well as their interpretation.
The numbers and conclusions are not consistent with the past history. My Android App is currently showing 310 for Beijing, and 267 for Shenyang. On November 10 this year there was an article on BBC News claiming that the 1400 measured in Shenyang were the worst one ever. But to be honest, the Halloween last year in Shenyang was even worse than this Nov 10. It is hard to give a number because above 1000 most measurement devices just refuse to report. But I currently live in Shenyang and you develop your own sense of estimating the pollution by looking for known buildings in the sky, by smelling, and by listening by to your lungs. Shenyang didn't shut down last year, where you couldn't even see past 50 meters (about 55 yards) due to the smog.

The government won't let you do measurements or post them in the wild. A colleague of mine made some measurements in the office using a state of the art device bought in Germany for PPM values. After recording bad numbers, he tried to convince management to upgrade the air filtering system in the building, they didn't accept these values, because they had to be done using a government-approved system. Same issue when we wanted to measure led content in the water at our residence compound: we were not allowed to do it in our lab, we had to do it through an approved third party company.

Now to be honest, I do understand the government. It would be very easy to spread terror and false information across the masses; and no offense, but many Chinese are not good in interpreting and digesting information. So the government is careful with that, and it is not an entirely bad thing. That said, you are never sure if you can trust official figures.

But that said, I still don't understand why now all of a sudden China and its air pollution is in the news. The air is crap, but it has always been crap. I don't think that this year is worse than last year (although it is still very very bad).

The thing is that most Chinese don't give a fuck. I work with Chinese engineer colleagues, and none of them has an air purifier at home, not even if they have small babies. So I see a combination of many things here: extremely bad air, a suspicious attempt to make the situation look worse than before, inaccurate or fake numbers, and a mass population that is either ignorant or just don't care.
My two cents.

Comment Lines of code? (Score 1) 618

I don't work for VW, but I have worked many years developing software for major automotive OEMs. It's funny how often I read here in Slashdot that this detection was probably coded in one line, or in a few lines, etc. Slashdoters need to realize that most automotive powertrain software nowadays is developed using model-based software, such as Simulink. The mechanical engineers developing powertrain software have literally no clue about source code, operating system, real time systems, interprocess communication, bus latency, code generation. And they do not really need to know either.

So the proper statement should be something along the lines "this detection was probably a single switch block or a single if block in your model."

Comment no offense, but indeed in the 90s (Score 1) 100

Although your post is informative and accurate, I think you are slightly missing the whole picture of what the parent poster was trying to convey. As far as cellphone technology is concerned, the US is indeed in the 90's. Not just due to locking, but in many other different aspects as well.

call price model:
- the US is about the only country in the world where the recipient pays for incoming calls when not roaming. I leave it as an exercise to the read to think why this is plain ridiculous.
- the prices are plain crazy. In Europe you pay max 30-50 Euros per month for unlimited plan, with 1GB or data. Less if you don't need unlimited. I payed about 15 Euro/month for moderate calling and 1GB/month, with the option to purchase on-the-fly 1GB extra for additional 3 Euros if you run out.
- in the US, if you exceed your limit, you get a heavy bill. In Europe, your data speed simply decreases down to GPRS.

- the US has many many dead areas. I know, it is a big country. But the fact remains.

Carriage involvement:
- incredibly intrusive branding, crapware, etc
- carriers are involved in certifying which phones are supported in their networks, the software update process, etc. which is none of their f*ing business.
- they use non-compatible networks.
- Their customer service is such crap that I don't know where to start.

All in all, this puts the US model of cellular communication really in the 90s. The unlock issue is just the cream on the top.

Comment Re:Profit (Score 1) 96

Since most people don't have a clue about audio and just follow marketing trends, you are probably right on spot. Now most of us here in Slashdot should know that noise cancelling headphones only knock out low frequency noise, like the engines. Conversations don't get cancelled at all. All the contrary, quite often you can hear them better when wearing such headphones, because the sound of the engines don't stay in-between.

For a better cancellation use noise isolating (passive) the in-ear earphones with foam tips, like the ones from Shure, westone, etymotic research, etc. They'll cut out a lot more than noise cancelling headphones, and they sound a lot better.

Comment Re:Dead reckoning technology is very old (Score 1) 151

You are correct. Particularly dead reckoning based on stars has been used for centuries for navigating across oceans. I was referring mainly to computer-based dead reckoning, which involves quantifying the error of your estimation based on a mathematical model, and how modern dead reckoning works.

Comment The different buses... (Score 2) 109

Most cars have a high speed CAN, for all functions needing messages at a rate of about 10 or 20 ms like Abs, engine, etc. There is also a low speed CAN, which is used for things like heating, and low rate signals of about 100 and 200 ms. The advantage of low speed CAN is that it can be put into low power and use it to wake up devices, like a wake up on LAN. I Then there is the LIN bus. This is a low speed, single wire cheap bus. It is used for things like wipers. These are the basic three buses.

Cars like BMW and Mercedes have two or three high speed CAN, a MOST bus for entertainment, and a flexray for safety critical applications. Other manufacturers use TTP instead of flexray, but the safety and timing is in both cases the main reason for not using CAN throughout.

Cars are also slowly rolling out Ethernet, mostly due to the high speed and low cost.

All buses are connected to each other in one way or the other via dedicated gateways. These gateways are usually not pure network gateways, but standard ECUs used for vehicle functions, also serving as gateways.

Then there are internal buses. For example some controllers include multiple ECUs connected via SPI or similar. The engine ECU is almost always connected to the CAN bus because it requires a lot of information from other systems, such as speed, gas pedal input, etc. The actual firing of the sparks is very time critical, and this is after done via a dedicated TPU controller, integrated as a sub core in the engine ECU (take a look at the MPC555 documentation), connected to the main ECU via an internal bus.

The point is that no one gives a Shit if you Fuck up your car by plugging something to one of the vehicle buses. From the OEM perspective, the car must be non hackable from the outside, but once you are in, it's your problem.

Comment No, you can't send. (Score 1) 109

I spend a little more, I can get a full CAN-bus connection and actually *send* information and control things.

No, you can't send over CAN this way, at least not without risking messing up the core structure of your network. Most nodes in vehicle CAN send messages periodically. Each message type has a unique id, and sending two messages with the same id at the same time can result in collisions. But even if these don't collide, they will get overwritten right after by the next real message. If the inconsistencies are bad enough, the safety fuses will catch them and shut the system down. Any respected automotive OEM implements such mechanisms. I In CAN it's not possible to intercept messages and perform a MIM attack, unless you hack into a gateway like LIN or flexray to CAN.

I work with for the automobile industry and quite honestly, I'm sick of reading this type of articles where people gain physical access to the OBD or vehicle bus, including the respective network databases, and claim to have hacked a car. It is like saying that a house is insecure because you can break into it, turn on the stove, and cause a fire with it.

If you can hack the car from the outside, give me a call. But don't pretend to be a hacker by exploiting things that were never meant to be protected. We are encoding things that we care about and if the CAN is not encoded, is because we don't care about you fucking up the bus communication. On the contrary, we will most likely end up crashing your car and buying a new one.

Comment Dead reckoning technology is very old (Score 1) 151

Dead reckoning technology is actually very old. It has been used to guide missiles, submarines, and of course cars for decades even before the GPS was invented. It is the technology used by sailors before they had GPS as well. The idea is simple and complex at the same time: use some specific known reference, guess what's happening in the absence of reference, and recalibrate once a new reference becomes available again . References can be the sun, stars, towns, or GPS itself.

In car dead reckoning, in contrary to what the article says, you typically don't use acceleration sensors. You typically use vehicle speed and yaw rate sensor. This gives you enough information to determine whether you've turned, and where you are along the road. If you can safely assume that you are following the road on your digital map, this is actually quite accurate. It becomes tricky if you are airborne and free to fly around, but also possible.

The nice thing about GPS is that the kalman filter used to compute your position and velocity can be easily extended to include additional sensors such as yaw rate and speed, available on any modern vehicles CAN bus. The only trick is to have the navigation system hooked into the vehicle, and this is one of the main advantage of built-in systems (the other being driver assistance functions taking advantage of map data for enhanced functionality)

I think there were some navigation systems manufactures trying to achieve similar results by adding accelerometers to the receivers. Since people usually use these devices to follow a guided route, a yaw rate sensor to detect turns is not essential, and detecting stop conditions in urban canyons or tunnels can be detected via accelerometers.

The possibilities are endless and they have been used forever in the navigation industry. The article is extremely misleading by claiming that this is new, or hasn't been done before. Nevertheless a cool technology.

Comment not me (Score 5, Insightful) 379

With all respect, I don't want to stop hearing these news. Because I want *confirmation* of every single thing that the US has done against people's freedom. I don't want to be considered a tinfoil hat paranoid anymore. I want proof, so no one can neglect later, about how fascist he US has become. And just because it was suspected, it doesn't mean that it is ok and we can just keep going with our lives as if nothing had happened. I want to see people resign, and I want to see people get spit at publicly, and ideally --even if it's never gonna happen-- I'd like to see people going to jail not only for having violated the most basic human rights, but for trying to brainwash the uneducated into believing that this is the correct approach to protect US's national security.

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