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Comment Re:GPS + WiFi (Score 1) 151

Okay, dumb question, but why does this work? I understand geolocation fine, but it seems this would only work if there is information in the wifi router as to where it's located. I know I never put in a lat/lon when I set up my wifi, how would it work without a knowledge of the wifi router location? Is it somehow auto-populated from transit times to various other routers or switches that DO have lat/lon info?

Comment More time... (Score 1) 156

"I visited with industry representatives and they have agreed to spend some time gathering input before we move forward with a public hearing"

I read this is, "I need more time to let Comcast and Time Warner buy off a few more politicians on the board. Then we'll ram it through regardless of what people think."

Comment Re:V2V Developer (Score 1) 390

You have to have a certificate that is digitally signed by a trusted authority in order to send messages considered valid. There is no identifying information sent out from your vehicle. Even your certificate is changed out every few minutes from a set of certificates (and that set is rotated every week or so). Really the whole security model is made to make it so incredibly easier to do things like track your cell phone, use cameras, or just old fashioned following to get any information than to get it from the V2V protocol. I encourage you to read about it, the IEEE and standards bodies have really thought about security from the very start. They knew nothing would derail it faster than people's fears about misuse.

Comment Re:Better you look the road (Score 1) 180

Check out the DSRC (Dedicated Short Range Communications) standard. Also labeled WAVE (Wireless Access in Vehicular Environments) and 802.11p with IEEE 1609. Basically a vehicle status message is transmitted multiple times a second and vehicles within a few hundred meters can receive these transmissions and act on that info. So when someone tries to turn left in front of a motorcycle that is transmitting it's vehicle status (location, velocity, size) the corresponding receiver on the vehicle will compute the collision course and put out a big warning to the vehicle. Once the system gets reliable and secure enough perhaps the vehicle will even do things like put on the brakes or prevent someone from running a deep red light.

The National Highway Transportation Administration is expected to decide any day now if it will be required in vehicles starting in a few years. Also systems are starting to crop up that are small, perhaps even integrated directly into smartphones someday.


Comment Re:Matlab will fall, SciPy will rise (Score 1) 465

Speaking as someone who used to use Matlab exclusively and almost got a job with the Mathworks let me say that I hope you're right. I love that scipy gives me a general programming language, and I love that it's free.

But there is one major obstacle before that happens...toolboxes. I'm in the DSP realm too and the signal processing package of scipy just doesn't hold a candle to all the numerous toolboxes that you can get with Matlab. There are some BASIC functions that are missing from scipy and there are a TON of extra functions in the Matlab toolboxes that aren't anywhere close to being implemented in scipy. The communications toolbox alone has so much that scipy doesn't offer it's not even funny.

I guess I should stop complaining and start contributing. But I honestly don't know that I'm good enough of a programmer to feel like I could contribute something. I guess I'm pretty sure I could implement a few algorithms without major bugs, so maybe I should pitch in. I don't know that it would be the prettiest or most optimal, but you've got to start somewhere.

Comment Re:Bullshit we won't notice (Score 1) 466

Agreed. I'm 6'5" and sometimes I have to travel for work. I would have to pay for the difference for first class, which is obscenely more money than I can spend on flying. I usually can barely get by in seats, most of my height is in my torso and neck. When the person in front of me reclines their seats I go from having an inch of legroom to a searing pain in my kneecaps from the collision. After that I can't have my knees bent, I have to stick my legs in the aisle or try to straighten them below the seat in front of me.

Comment C/C++ (Score 3, Interesting) 465

I'm a MSEE and I've been working in the digital signal processing realm for the last 10 years since graduating. I should mention that I haven't done a lot of low level hardware work, I haven't programmed actual DSP cards or played with CUDA. I have written software that did real-time signal processing just on a GPU. Everyone in my industry at this point uses C or C++. There is some legacy FORTRAN, and I shudder when I have to read it. Some old types swear by it, but it's fallen out of favor mostly just because it's antiquated and most people know C/C++ and libraries are available for it.

For non-real-time prototypes I'd recommend learning python (scipy, numpy, matplotlib). Perhaps octave and/or Matlab would be useful as well.

At some point you have to decide what your strength will be. I love learning about CS and try to improve my coding skills, but it's just not my strength. I'm hired because of my DSP knowledge, and I need to be able to program well enough to translate algorithms to programs. If you really want to squeeze out performance then you'll probably want to learn CUDA, assembly, AVX/SSE, and DSP specific C programming. But I haven't delved to that level because, honestly, we have a somewhat different set of people at the company that are really good in those realms.

Of course, it would be great if I could know everything. But at the moment it's been good enough to know C/C++ for most of our real time signal processing. If something is taking a really long time, we might look at implementing a vectorized version. I would like to learn CUDA for when I get a platform that has GPUs but part of me wonders if it's worth it. The reason C/C++ has been enough so far is that compilers are getting so good that you really have to know what you're doing in assembly to beat them. Casual assembly knowledge probably won't help. I might be wrong, but I envision that being the case in the not too distant future with GPUs and parallel programming.

Comment Texting while not at red light (Score 1) 1440

I wonder what the correlation is between the following activities:

texting while at a red light texting while driving a moving vehicle
not texting while at a red light texting while driving a moving vehicle

I'd bet it's higher in the previous case. If someone starts a text at a red light, and they just have a few more words when the light turns green, how many people are disciplined enough to put the phone down? As a cyclist texting while driving is a very important issue to me.

Of course, correlation isn't guilt. But careful, that's a slippery slope. Next thing you know that argument can be applied to drunk driving, financial regulation, and hate crimes, and your on your way to libertarianism, which seems to be a very bad thing at this website.

Comment Re:jerk (Score 2) 1440

Traffic related fatalities are on par with the amount of gun deaths in the U.S. http://www.usatoday.com/story/news/nation/2013/01/09/guns-traffic-deaths-rates/1784595/. Plus traffic related fatalities is the leading cause of death among children 2 to 14 years old http://www-nrd.nhtsa.dot.gov/Pubs/810803.PDF.

One can make the argument that it's not clear the current method of enforcing traffic laws is actually helping those statistics, but that's another point (although the following article says speeding is the leading cause of traffic deaths in NYC: http://www.streetsblog.org/2013/03/18/dot-speeding-the-leading-cause-of-nyc-traffic-deaths-in-2012/). I personally think it's barbaric how many of our deaths and injuries come from vehicles. If you ask me more autonomous ways of driving couldn't come soon enough, in whatever form that takes.

Comment Smileys and parenthesis (Score 1) 169

Interesting interview. Surely there were more important topics but if nothing else this interview was useful in that it taught me it's okay to use the parenthesis at the end of a smiley to serve double duty as the end of a parenthetical statement (kind of like this one :-). At least when your smiley is left in plain text, that is.

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