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Comment: Re:But....Profits! (Score 1) 280

by kaiser423 (#49450321) Attached to: The Myth of Going Off the Power Grid
At least locally, the upkeep costs the utility companies are proposing vastly outstrip their actual costs (aka, if every solar owner paid it they'd more than triple their maintenance budget). Second, the energy distribution is necessarily local (aka they're not shipping your residental solar power to somewhere hundreds of miles away), and has been shown to actually defer costs -- an internal report that the residential solar load lessened the amount of power needed to the city, putting off a major line upgrade costing tens of millions for at least 5-10 years. A cost that the utility otherwise would have had to distribute out, so at least in some instances it can lessen capital costs since major line upgrades for extra capacity are needed less often -- a nice benefit of distributed generation, you don't need such massive trunks lines.

I don't have solar, but can definitely see this for what it is -- trying to crowd out something that they don't like.

Comment: Re:Bad idea (Score 1) 671

by kaiser423 (#49176245) Attached to: Snowden Reportedly In Talks To Return To US To Face Trial
See what they did to Chelsea (formerly Bradley) Manning. They locked her up in solitary for extended periods and really did just about everything that they could to make her mentally break. Very punitive, and if you ask me god-damn un-American. Lots of people tried to draw attention to the fact that the judicial system was totally fine with mentally and physically breaking a person before even going to trial, but hardly anyone even cared. If I was Snowden I would've seen that, and decided to get asylum somewhere until I was able to reasonably ensure that they wouldn't do the same to me, and then come back for trial. Snowden has always indicated that he is fine with standing in court over his actions -- but he is not fine with cruel and unusual punishment before the conviction and a railroaded process. I say bring him back and show that we can put on a fair trial and treat our accused with at least the most basic human dignity.

Comment: Re:Is this really a problem unique to devs?? (Score 1) 347

by kaiser423 (#49144713) Attached to: The Programmers Who Want To Get Rid of Software Estimates
Great post. This then doubles with EVMS -- the new government way of creating estimates and schedules. You have to hack out the software development so fine that at the proposal or initial program startup phase, you better know every class and architectural detail, because you're not allowed to add anything without an expensive replan, but you're also not allowed to have non-specific tasks, or tasks that take longer than 44 days -- but that's the baseline task, so typically the software portion of it can't be longer than ~10-20 days. I do pretty good with getting the schedules in, but that's because I'm a PM that writes lots of code too, and does EE/RF work, so I can hack it in. But in a lot of other schedules from other people, it's really just GIGO -- garbage in, garbage out.

Comment: Re:Ha (Score 1) 45

by kaiser423 (#49137605) Attached to: The Believers: Behind the Rise of Neural Nets
Yea, I'm with you on people not getting it. I wanted to show people a picture of a shed that I had taken a couple of months back. It was buried under hundreds of photos, so was hard to find. I just punched in "shed" into the Google Photos search for my photo collection and low and behold dozens of pictures of different types of sheds in different angles all showed up in my search results. Typing in "brown shed" filtered it down to brown, and then "light brown shed" gave me just the light brown shed, which is what I was looking for.

I was pretty damn impressed, and pretty much every common day object I searched for, I got pictures back with that in it, very accurately. Screw manually tagging pictures (all the rage a couple of years ago), a computer just goes through and classifies them. Everyone else didn't see it as a big deal -- "so what, they figured out a light brown shed". Without really realizing the sheer amount of computing horsepower and sophistication that went into something like that.

Comment: Re:Real problem (Score 1) 374

by kaiser423 (#49129531) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt
Yup. Local power company in New Mexico came up with a $60/month charge for their maintenance charge for solar users if they're not drawing electricity off the grid. That's higher than quite a few people's actual power bills and is not in line at all with what it actually costs to maintain that grid tie.

Comment: Re:How do you get 1Tbs in 100MHz of BW? (Score 2) 71

by kaiser423 (#49120413) Attached to: UK Scientists Claim 1Tbps Data Speed Via Experimental 5G Technology
You make multiple measurements, and you get more fine grained measurements. Originally you had on/off keying (AM modulation). On = 1, Off = 0. You had FM modulation, where +freq = 1, -freq = 0. It's easy to see how to make either of those better -- for on/off keying, a simple amplifude modulation. Full power = 11, 2/3rd power = 10, 1/3 power = 01, off = 00. Boom, double the bit rate in the same amount of bandwidth (technically, potentially a little bit less if you do things right). You can see how you can infinitely divide that -- you can track 4, 8, 12, 16 power levels, etc. You can do the same thing with the phase of the carrier -- change phase by half phase intervals, or quarter, etc. Then you can combine the two and end up with a constellation of points, which is basically QAM. You see QAM-16 (16 discrete phase/amplitude points), QAM-64, QAM-128, etc.

Now, if you've been thinking about implementation details, you realize that the fundamental question is: "how do I know that I'm at half power instead of full, or my phase has changed?". Well, there's basically a synchronization period -- you listen to the stream for long enough to kind of know where you are at. Some streams also send synchronization patterns periodically. The next issue then is "what happens when my signal fades, or my signal bounces and the phase gets screwy". The answer then is in algorithms and multi-hypothesis guesses as to how the channel medium is acting. Lots of math there, but no matter how good you get more highly advanced tighter packed schemes are going to be more vulnerable to things like signal fades, etc and then also take more time to get back up to speed because you need more symbols flying by you to sync up to where you are at. But you can push them at a higher rate, so you gain some of that back. You end up wit ha constellation that you synchronize to, and then to make it more complex, Fourier tells us that if the bigger phase/amplitude change you have per bit period, the more bandwidth you occupy. So, actually, sub-dividing the phase/amplitude helps you generally occupy less bandwith, but you can also get tricky where the constellation is adaptive in such a way that you minimize amplitude/phase changes for each bit set transmitted, making you occupy even less bandwidth. But that's one more thing for the receiver/transmitter to keep in sync....

As you can see, this gets incredibly complicated quickly. It's a very math heavy field, with lots of very neat, clever tricks to make it all work seamlessly. These guys just figured out how to maintain coherency, etc at higher frequencies, which is fairly notable, but this march is expected to carry on as we get faster processors, higher performance amplitude/phase modulators, and low noise devices we can keep packing those bits tighter and having more points on the constellation.

Comment: Re:Question! Shouldn't multiplexing be priority? (Score 2) 71

by kaiser423 (#49120187) Attached to: UK Scientists Claim 1Tbps Data Speed Via Experimental 5G Technology
It already is multiplexed, via multiple access schemes. You typically see 3 antenna sets arrayed on a cell phone tower. Each of those typically operates at a different frequency set so that they don't interfere. Then in each of those coverage ares you're typically multiplexed via TDMA, or you're given time slices in which to communicate. There's only so fine that you can dice up time before either your calls get choppy, or not everyone in the cell can get synchronized enough to communicate effectively. Over the last couple of years, you've seen cell providers rolling out more and more stringent timing requirements to their sites, so that they can reduce the guard-time between slices and also ensure that all phones/devices are synced up better so that they make better use of their actual time slice.

There's definitely more to it than that in a typical cell site (including other ways to add more users), but at some point you have to deal with physics. You have a certain amount of bandwidth at your frequency to use, and no matter how clever you get, there are thigns like noise, interferers, limitations on the sophistication of hardware you can put at cells or in phones, the laws of physics, etc. You hit hard limits pretty fast. One of the main reasons Verizon and some of the US networks went to CMDA was that at the time you could pack in more users per channel, because you weren't limited by timeslices, you were limited by SNR (more users effectively increased the noise floor since their codes wouldn't correlate), so you could get some pretty impressive numbers of users per cell, making deploying a network cheaper. Newer 4G and advanced 4G waveforms are kind of an interesting combination of an optimized waveform that's TDMA based, but has some similar features to other networks.

This high speed is relevant, because you usually can use some of the techniques to divide up the bandwidth effectively to get more users per cell -- you can have smaller timeslices to transmit if the amount of data you can transmit in that timeslice is massive. The maximum amount of data passable over a link is kind of an industry standard metric for how much capacity a given channel can handle. It's easier to grok than channel capacity, etc

TLDR: We're trying our damned best to multiplex as many users as possible into a cell site. The more that you can get in one site, the cheaper it is to operate and deploy networks, so tens of millions of dollars annually is spent making it better, and the strides that have been made are pretty darn impressive. But we still have work to do!

Comment: Re:18B on 75B (Score 1) 534

by kaiser423 (#48923475) Attached to: Apple Posts $18B Quarterly Profit, the Highest By Any Company, Ever

If you run at single digit margins you have absolutely no ability to invest in development.

I agree with you in general, but to be fair that 24% margin is *after* all of the R&D, internal investment, etc, etc. So they could keep everything at the same level, which is among if not the highest in the industry, but 20% drop in price and still make 4%. This is true profit -- after everything else has been paid for -- if it was just an amortized profit per product without all the external costs wrapped in, then yea, 24% is not very healthy to begin with and 4% would put the company out of business.

Comment: Re:Size (Score 2) 324

by kaiser423 (#48869663) Attached to: What Will Google Glass 2.0 Need To Actually Succeed?
Not just size, but I think it needs to stop focusing on the consumer market. They're a couple of generations out from getting is small and useful enough that consumers will adopt it -- even if they make it very small, it's not going to be totally hidden and people will get anxious about whether they're being recorded or not.

But in the commercial space, every single person on an assembly line could benefit from this -- the F-35 has projects and computer vision systems to overlay work instructions, rivet patterns, and check whether they're in there right. You have to design the assembly line around not obscuring the projectors that are telling you what to do. Making it on the operators face, but doing the same job would be a massive boon. Police officers recording interactions. Medical professionals pulling up charts, etc. There are a couple of very viable commercial uses that they should use to survive and refine over a couple of generations until the tech gets to the point of being able to be packaged into a consumer friendly package. Honestly, spin off a small lean company to keep it alive in the commercial sphere for 5-10 years and then absorb back into the mothership.

Comment: Re:I hope they succeed, but... (Score 2) 426

by kaiser423 (#48793469) Attached to: Chevrolet Unveils 200-Mile Bolt EV At Detroit Auto Show

I hope that this effort of GM's succeeds at least well enough for them to continue R&D into EV's, but there are 2 significant problems I see that they'll need to overcome: First, they'll need a high-speed charging network that will allow for long-distance road trips...Second, the established dealer network has no interest in selling EV's.

I've always had this question, and I think that I know the answer (that the Big 3 aren't serious about EV's yet). There are dealerships *everywhere*, and they're large and have service bays. If any of these Big 3 were interested in EV's it wouldn't take much to help turn dealerships into quasi supercharger stations, where service and maintenance can also be performed. Heck, battery swaps too if the tech gets there. I think that once the Big 3 finally come full bore into EV's that the dealership network is going to have to be key to their strategy. Dealerships are independent, but if they help out and come up with the right incentives to put solar panels on dealerships and install fast charging stations, they could effectively cover all of the US in charging networks very, very quickly.

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