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Comment: Huge differences (Score 1) 161

by jimmyswimmy (#47554199) Attached to: OKCupid Experiments on Users Too

There's a huge difference between A/B testing, designed to optimize your website with the direct intent to improve sales, and performing experiments on how different news feeds affect your users' moods. A/B testing typically comprises changes in button size and color, website layout, font variations, etc; should we lead with the price, or with the benefits, or with something else? On the other hand, what FB and OKC are doing - admitting to, and proudly! - amounts to wholesale experimentation on their users, with undisclosed intent - perhaps to make the users come back more frequently for another hit.

This seems akin to me to cigarette companies manipulating the nicotine content of their products. That didn't go over well when it was finally disclosed.

You can't just tell people you "might" experiment with them, they have to know and understand that they are part of an experiment. They don't have to understand the goal, they just need to know what they are part of, and they have to consent to that experimentation. One could argue that A/B testing should submit to the same level of scrutiny as other psychological experiments, but I think people generally understand and accept corporations' profit incentive. We don't accept the idea that a company might wish to screw around with our mood or set us up on a date when they know it won't work out.

Comment: Re:Astronomy, and general poor night-time results. (Score 1) 547

by jimmyswimmy (#47525971) Attached to: Laser Eye Surgery, Revisited 10 Years Later

I've actually done exactly that, but not for that purpose. One eye is laser corrected to ~20/25 (degraded over about 15 years to about 20/35). The other eye can find the 'E' on the chart if you tell me which wall the chart is on. When I really need to, I put a contact lens in one eye (which gets the uncorrected eye to about 20/10). Otherwise I walk, read, work, type, drive, fly, etc. with what I believe is called monovision. It's easy. The world looks to me like normal, except that on the one ("bad") side I have very wide range of peripheral vision. I see whatever I focus on in good clarity.

It's amazing what your brain can compensate for. I can't wear glasses, though, that causes headaches.

Comment: Re:I am totally impressed (Score 2) 237

by jimmyswimmy (#43716765) Attached to: Intel's Haswell Moves Voltage Regulator On-Die

Not such a big breakthrough as you'd think. As you increase the switching frequency you can decrease the value of inductor and capacitors required. Last CPU supply I built - 10 years ago! - used 100 nH inductors at 300 kHz per phase. I skimmed the PSMA article but there was mention of MHz operating speeds, not at all unheard of these days, so the components ought to be much smaller. A 10 nH inductor and some hundreds of pF of capacitance seems very feasible without stretching the bounds of silicon technology at all.

Comment: From a former power supply designer - Neat! (Score 5, Interesting) 237

by jimmyswimmy (#43716161) Attached to: Intel's Haswell Moves Voltage Regulator On-Die

That's some amazing work. The current state of the art in CPU power supply designs hasn't changed in 15 years. 12V in, low voltage out, and the output voltage has been moving lower and lower for years, with designs below 1 V. If you figure you had a few percent of tolerance in the early years when everything ran off 2.5V and that few percent remains constant, then at 1 V you have almost no room for slop. So there are a lot of output capacitors there, both those electrolytics (you always hear people complaining about them but they're CHEAP) and ceramics. The ceramics cost a fortune and you need a lot of them to get your tolerance down - the first half microsecond of a load step is entirely the ceramic capacitor's response, not the controller or anything else. Moving part of the VR onboard allows them to reduce the parasitics significantly and they can probably tolerate a little higher tolerance as a result, but moreover they can get rid of some of those ceramics in the whole system - ultimately many of those on the motherboard.

So this is taking a lot of cake out of company mouths. Analog, Intersil, IRF, ON, who else - manufacturers of controllers, MOSFETs. Inductors, ceramic and 'lytic vendors are all going to lose out a bit here. Potentially Intel can reduce the platform cost vs. AMD as well, which is interesting. There is still an onboard VR but it will be 12 - 2.4 V, wherever they think the sweet spot is for efficiency and size. And the first real change in this industry for a long time. Cool work.

Comment: Not sure about books (Score 4, Interesting) 248

by jimmyswimmy (#42398161) Attached to: Amazon: Authors Can't Review Books

But reviews online are certainly corrupt. I don't use the star ratings for anything, unless an item only has a few reviews and all bad, and rely almost entirely on the BAD reviews for everything I purchase. If the bad reviews follow a common theme, it's a believable problem, and if I care about that problem vs. the price of the item, then I look for another item. Honestly I put less faith in the good reviews than the bad ones, especially when they're all glurge - no book, no product is perfect.

Comment: Nothing (Score 1) 180

by jimmyswimmy (#42157161) Attached to: Ask Slashdot: Tablets For Papers; Are We There Yet?

The IEEE standard for papers is still a two-column format, and the paper is only downloadable in PDF, so the first problem is that the paper is completely unreadable on anything other than your printed paper. PDF sucks, and therefore Kindle, ipad, etc. will all suck. This is totally fixable but I haven't seen an application yet that does it.

Other problem is that I like to literally draw on papers as I read them... to check the math, to call attention to something, etc. Nothing I have seen has as simple and easy to use of an interface as a pen and paper. Relatedly, when I desire to draw up a schematic or other technical drawing documentation, I have found that trying to do it on a computer is so complicated that it ruins my train of thought. It's not hard, per se, but compared with a marker on a whiteboard it sucks. Take a cell-phone-camera picture afterwards and it's preserved and digitized for ever.

Perhaps if Windows 8 takes off, and touch screens become the norm for all computers, and we can get rid of this ridiculous abstraction of a "mouse", we'll be able to accomplish more of these tasks on a computer. Still, for brainstorming or putting simple thoughts to paper, I don't know if I can see a future use case where the tablet takes over from pen and paper/whiteboard and marker. Unless doing it on a tablet adds something, it's just not worth it.

Comment: So what? (Score 1, Insightful) 138

by jimmyswimmy (#41862233) Attached to: Most US Drones Still Beam Video Unencrypted

So what if the video is transmitted in the clear? What does that get you...

- against a sophisticated enemy? They already know you're there (radar, DF on the transmitted signal). You're flying around in a racetrack centered on your target, so even without the video they know roughly what you're looking at. Problem is solved by an enemy air-to-air missile, or they ignore you and watch you watching them.

- against an unsophisticated enemy? They don't even know to look for the signal in the first place.

- against an enemy marginally capable of receiving the video signal? Use more channels, change encoding schemes so that COTS equipment can't pick it up so easily. Or yeah, encode it. But encoding video is fairly difficult considering the need to do it in realtime with limited processing capability and no tolerance for latency (and this is the real reason video is still transmitted in the clear - it's expensive to do anything but!). Or embrace it. Maybe your enemy can see you watching him - that can be played to an advantage.

Comment: Re:You can have 2: cheap, realtime, or resolution. (Score 1) 549

by jimmyswimmy (#41785457) Attached to: Why Can't Industry Design an Affordable Hearing Aid?

Just to hit on the basic point parent was discussing - that digital filtering is undesirably slow yet perhaps the best way to go...

I am not a hearing aid designer, but I've built lots of sensors. It would not be difficult to build an all-analog circuit with an ability to tune the gain on specific frequency bands via a digital potentiometer. When you have a lot of different, narrow bands it becomes challenging to fit all that in a tiny package. If it were just that, you could have the electronics for ~$50. Of course there's much more to a hearing aid than a few transducers and gain stages though.

Comment: Re:Kindle Non Touch (Score 1) 126

by jimmyswimmy (#40931409) Attached to: Ask Slashdot: Rugged E-book Reader?

I have a Kindle 3G and, although I love the device, it is not nearly as robust as parent suggests. Even with a [thin] protective device, the screen driver has died on me twice. Once while in a remote location where I had literally nothing else to read but tech manuals, and the other time it fell off my dresser. Both times I was seriously annoyed. Amazon is very reasonable about replacements, and the first was free, the second was half price. I am still in love with my Kindle but recommend a spare e-reader at minimum and strongly suggest a few lengthy printed tomes as backup, something you don't mind reading twice (perhaps a classic, a compendium of fiction, etc.).

Comment: ReplayTV (Score 5, Interesting) 283

by jimmyswimmy (#39963211) Attached to: Dish Network Announces Prime Time TV With No Ads

I had a ReplayTV years ago that did this, which used to be a competitor for Tivo until they lost the pricing war (didn't take long!). Actually until a few months ago I still used it regularly to tape standard def TV shows, but then my "lifetime" subscription ran out... (let THAT be a lesson to you)

Anyway they had two incredible features on these boxes, from around 2003 until the service shut down. The first was commercial skipping, which worked reasonably well. The second was the ability to share recorded shows. Several communities sprung up around this capability, so you could request a show that you had missed from someone else who had taped it.

Predictably they were sued and that did not help their already troubled business model. But it's not such a new thing for commercial skip to be available in COTS consumer devices. And man I miss it!

Comment: Plenty of great uses for this (Score 2) 202

by jimmyswimmy (#39954207) Attached to: HP Shows Off Power Over Ethernet Thin Client

Receptionists, POS terminals, all kinds of good uses. This is the way I set up my computers at home - good desktop, cheap laptop with RDP. I could use one. Unfortunately no idea of the price. At $200 these will sell like crazy. At $400, may as well just get a big netbook. Knowing HP, they'll sell at $450.

Comment: Why update? (Score 4, Interesting) 270

by jimmyswimmy (#39150329) Attached to: The Dark Side of Digital Distribution

This is one reason why I rarely update anything on my Android tablet. I have a number of kids' games on there which never had many privileges when I installed them, so there's little security worry (plus it's only connected to my WLAN). What could "Draw by Numbers" possibly need to update to work better? The only "upgrade" I expect is them to remove pictures. My 3 year old is thrilled with the 10 or 20 different things she can draw on there, and that probably is limiting sales.

I only upgrade OS items now and disable the automatic upgrade checking for everything else. I'm sure I'll hear about why that's bad here. I think years of free and truly beneficial MS updates have confused a lot of us into thinking that an upgrade actually means what the word is defined to mean. Much like "gender" replaced "sex" I think the true meaning of the word "upgrade" is being replaced by something. Something not good.

Comment: Wavelength (Score 2) 307

by jimmyswimmy (#38202140) Attached to: Study Hints That Wi-Fi Near Testes Could Decrease Male Fertility

How is a signal with a wavelength of 5" (wifi is around 2.4 GHz, 2.4E9/3E8*39.37in/m=4.9") supposed to interact with a human sperm, which, according to wikipedia, is comprised of a head 5 um long and a tail 41 um long, all of which total 0.002 inches. These arguments never ever make any sense to me.

Comment: Re:Makes sense (Score 1) 186

by jimmyswimmy (#37807344) Attached to: DARPA Proposes Ripping Up Dead Satellites To Make New Ones

Parent is exactly right. In the defense-sciencey world, there is a whole class of problems often called DARPA-hard. I think the term is one DARPA itself uses. My company recently missed out on an opportunity to bid a project for DARPA because we had an approach based on current technology which could be fielded very quickly. DARPA doesn't do that. DARPA does crazy, hard projects with the goal of advancing technology. This is definitely an area ripe for DARPA - it is a high risk, high payoff application.

Suppose this works - the cost of putting a new bird in orbit drops significantly. Rather than destroying a satellite that isn't working quite right, you could salvage it for parts the way we do a car. So first, you haven't wasted these space-qualified and tested components, but even better, you don't have to fly new ones up there. That's not just money, it's also time. You might be able to extend the effective lifetimes of various satellite constellations, such as GPS, Iridium and GLONASS, and thus improve reliability of such systems.

There's a fairly obvious flipside, as well - I don't know if there is international law on satellite ownership, but the law of salvaging seagoing vessels is quite clear - finders keepers. You sink a boat and I find it first, it's mine to sell - including its cargo. I don't know how this applies to space, but there is a pretty obvious (to me) parallel between a sunk boat and a grossly nonfunctional satellite. To clearly state my point: suppose a Russian spy satellite breaks, and we have this capability - we could take it and break it apart and do as we like to it. Of course if not done covertly the Russians would simply destroy one of ours, but it is interesting to consider the possibilities.

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