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Comment: Re:Is this really a problem unique to devs?? (Score 1) 341

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) 359

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.

Comment: Re:Precious Snowflake (Score 1) 323

by kaiser423 (#48653377) Attached to: Putting Time Out In Time Out: The Science of Discipline
To be fair, she is using data. Most of the Psychologists at the time that the stupid Self-Esteem movement that was happening in education was incorrect and were pretty aghast. They *knew* from their studies, etc that that approach isn't particularly effective. It was more the stupidity of our educational system that was the fault of that one.

I'm all for data driven stuff; although Psychology is a tough one -- it's incredibly hard to effectively account for all the variables, and I think that she may be reading into the data bit much, as can happen in the field.

Comment: Re:Someone has (Score 2) 270

by kaiser423 (#48575841) Attached to: Keurig 2.0 Genuine K-Cup Spoofing Vulnerability
I don't even know what you're talking about here. Up until a year or so ago, none had DRM. And you don't need to remove anything to use your own coffee grounds. I have quite a few reusable K-cup sized filters that I've been utilizing to put my own grounds in forever without modifying the machine. I've never actually met anyone that didn't have at least one -- eventually if you drink coffee, you realize how much money you could save with one of those versus the K-cup.

I use the Keurig for when I have multiple people wanting something. I like my coffee incredibly strong, so most people don't drink my french press coffee. But with the K-cups, they can get coffee, tea, whatever without me having to expend any extra effort. Makes hosting people easier than reworking my fancy coffee setup for 12-18 cups of coffee.

Comment: Re:Interesting if done right (Score 1) 67

by kaiser423 (#48569857) Attached to: BitTorrent Launches Project Maelstrom, the First Torrent-Based Browser
I'm a bigger fan of HTTPS everywhere over this. As far as I can tell, this would break a lot of that....But it still could be a boon for imgur, and other picture/video hosting sites. Makes sense, but I think that the trend towards encrypting everything clash with this idea pretty well.

Comment: Re:simple (Score 1) 193

by kaiser423 (#48506415) Attached to: Chromebooks Overtake iPads In US Education Market
Playing with some friend's Chromebooks, they really do seem to have a drop dead simple administration backend. They're simple, can pretty much only do what you need them to do for school and seem to work at a good price. My friend had test trialed iPads versus Chromebooks and went with Chromebooks mainly due to durability. While they do pass that cost onto the student, it was much, much easier to crack an iPad's screen, which replacement cost as much as just a new chromebook. He has a pretty good chromebook junkyard that he lets the kids have access to to fix things before they have to pay for a replacement.

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