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Microsoft Announces Windows 10

Solandri Re:Missed opportunity (622 comments)

Can't call it Windows X - too easily confused with X Windows.

No confusion at all.

Win X
X Windows
= Win X

Hey it works for a bunch of other FOSS projects.


Consumer Reports: New iPhones Not As Bendy As Believed

Solandri Forces vs. moments (302 comments)

I'm a 2-decade subscriber to Consumer Reports, but sometimes they just get their science (engineering) completely wrong.

A force doesn't bend an object. A moment does. That is, the propensity to bend is not proportional to the force applied. It's proportional to the force times the lever arm. i.e. A 90 pound force applied to one point on an object may not bend it, while applied to a different point it can easily bend it. So the bigger (longer) phones were actually resisting greater moments, even though the force was the same.

Another problem is the test they came up with supported the phone at both ends, while pressing down in the middle. Basically a simply supported beam. The important thing to note here is that in such a config, both sides of the phone are resisting the bending moment. If it took 90 pounds of force applied to the middle, then the left side was resisting 45 pounds, the right side 45 pounds.

When a phone in your pocket is bent, it is in a cantilever configuration. One end of the phone is held rigidly, while the other end is free-floating. If the phone reached sufficient deflection to permanently bend in a simply supported config at 90 pounds, it will reach the same deflection at just 45 pounds in an equivalent cantilever (more precisely, 45 pounds pushing one way at one end, while your body weight holds the other end of the phone in place). You can try it in the calculators I've linked. Give both the same load, make the cantilever half the length, and you'll see the cantilever has twice the deflection. Make the load on the cantilever half that of the simply supported beam, and they have the same deflection.

(The actual force and moment diagram when you're sitting on your phone is a lot more complicated, since the force is distributed along the phone instead of all at one point. Integrating this is trivial for anyone who's taken a structural engineering course, but explaining it is beyond the scope of a forum post.)

3 days ago

Researchers Develop Purely Optical Cloaking

Solandri Re:I had a similar idea as a kid... (59 comments)

Won't work. Well it work in one special case, but not in the general case. Any time the fiber path (defined by the two endpoints of the fiber) isn't parallel to line of sight, the light coming out the end of the fiber won't match what's directly behind that point. So if you place a camera in a specific spot, and you route the fibers from the front to the equivalent position in the back (relative to the camera), then it would work. But the moment you moved the camera, the fibers would then be at an angle instead of parallel to line of sight, and the "background" as seen through the fibers wouldn't align with the actual background. It also fails when there's parallax. Line of sight is diverging rays shooting out from the eye, so the fibers have to be aligned at that exact angle of divergence. If the eye is closer or further, there's parallax, and again the background through the fibers doesn't match the exact background.

Basically, your optical fibers are just mimicking putting a TV in front of the object and displaying an image of the background on the TV. A real cloak can't just take light which strikes a plane (sphere, whatever) on one side and emit the same light on the opposite side. It also needs to preserve the arrival angle of the path that light was taking as it struck one side, and emit it on the other side at the same departure angle it would have taken had the cloaked object not been there. Which this clever arrangement of lenses does (albeit for a very narrow field of view).

3 days ago

Utilities Should Worry; Rooftop Solar Could Soon Cut Their Profit

Solandri Re:Really? (491 comments)

Look at Germany. Solar has made coal and nuclear unprofitable.

That isn't something to be proud of. Solar is, by far, the most expensive way to commercially generate electricity. If solar has made coal and nuclear unprofitable in Germany, you guys are doing something seriously screwy. Germany's sunshine profile is absolutely terrible for solar. The capacity factor (ratio of actual annual generation to generation capacity) you can calculate based on Germany's annual solar power stats is around 0.1, compared to 0.145 for the continental U.S., and 0.185 for the desert southwest U.S. i.e. the same PV panel in the desert southwest U.S. will produce 1.85x as much electricity that it does if located in Germany.

Since there hasn't been some miraculous breakthrough in PV solar production efficiency, the only remaining possibility is that electricity prices in Germany have risen so high that solar has artificially become competitive. And that's precisely what you see. You guys have enacted laws making producing electricity cheaply so difficult, that the price has risen to the point where solar "makes sense."

4 days ago

Security Collapse In the HTTPS Market

Solandri Re:So offer a cost effective replacement (185 comments)

Why do you care when you are not liable?

Why do you think caring should stop with liability? The merchant who ends up paying for fraud just raises their prices to make back the lost money. So you are still paying for the fraud whether or not you're directly liable.

5 days ago

Indian Mars Mission Beams Back First Photographs

Solandri Re:The best photo... (113 comments)

The same is true for men. Research has shown that attractiveness has a significant positive correlation with winning a close election. The only real difference is that there are a lot of crass men out there who are willing to publicly vocalize the bias (which ends up being predominantly about women because that's whose attractiveness men predominantly obsess over), while women tend to keep quiet about it.

Getting people to not talk about it in public doesn't make the problem go away. You just have to accept that that's the way we're wired, and take measures to neutralize it when necessary. Like how Juilliard does its music auditions - with the candidates behind a screen so the judges cannot see them, only hear them.

5 days ago

IBM Solar Concentrator Can Produce12kW/day, Clean Water, and AC

Solandri Re:Plain solar panels cost less (268 comments)

Sure you can have these fancy concentrators, but nothing will cost less per kW than plain solar panels arrays or wind power. Why concentrate the suns rays instead of using solar panels, whose costs decrease all the time?

Concentrated solar power is a popular concept because mirrors cost a helluva lot less than solar panels.

Actually, my money is on plants, because they cost a helluva lot less than solar panels or mirrors. Yeah they're probably around 1% efficient compared to 16%-18% for most commercial panels. But who cares when plants are biological solar collectors which build themselves. No human intervention or energy cost needed (though it can help speed up the process). We just need to figure out a cost-effective method of converting cellulose into a more utilitarian fuel and we're set.

about a week ago

Users Report Warping of Apple's iPhone 6 Plus

Solandri Re:Third option (421 comments)

The material plays a large role too. Plastic phones don't have this problem because plastic can yield a much greater amount before suffering plastic deformation (permanent bending). i.e. They can bend the same amount or even more in your pocket, but they'll revert back to their original shape.

The actual failure mode in the iPhone 6 appears to be insufficient strength at the cutout causing enough deflection for the aluminum at the cutouts to buckle outward. At which point it's deformed plasticly and the phone is permanently bent. I'd posted earlier that the fix would be to put a reinforcing tab behind the cutout. But simply increasing the thickness of the cutout may be enough to prevent the buckling (i.e the phone would still bend, but there would be no buckling and no plastic deformation).

about a week ago

Users Report Warping of Apple's iPhone 6 Plus

Solandri Re:Not just iPhone (421 comments)

From the pics I've seen, the problem looks to be the cutout for the volume rocker. The thin strips of aluminum on either side of the rocker simply aren't strong enough to withstand the bending moments in your pocket, and end up suffering plastic deformation (e.g. doesn't revert back to its original shape). It isn't a problem in plastic phones because although they bend the same amount (or more) in your pocket, plastic has a much larger region of elastic deformation and thus never gets permanently deformed.

To fix it, they're going to have to add a reinforcing plate behind the volume rocker which extends the full thickness of the phone, with a cutout(s) for the electrical leads for the rocker.

Stronger glass or even a stronger metal back will make it stiffer (greater moment of inertia), which would be another way of solving the problem. But that's a generalized solution which would increase the stiffness of the entire phone, when it really looks like the problem is just this small area.

(And FWIW, I've always advocated that plastic is a better material for phones. Most metal phones end up being put in a case anyway, which defeats the whole point IMHO. Once flexible displays come down in price, it's game over for metal bodies and glass screens IMHO.)

about a week ago

South Australia Hits 33% Renewal Energy Target 6 Years Early

Solandri Re:costs (169 comments)

I live in Norway, we pay around $.12 including taxes and "line rent".
The price fluctuates with rain and season, but $.12 is about as high as it gets. I've seen as low as $.05

Most of the electricity comes from hydro plants (98.5%) and I think other renewables will have similar cost structure. High investment, very low marginal cost pr kwh.

Unfortunately, hydro is the only renewable with a levelized (i.e. including construction) generation cost low enough to compete with coal. Here's the historical US Department of Energy data on generation costs (median cost converted to $ per kWh):

$0.02 - hydro
$0.04 - unscrubbed coal
$0.05 - scrubbed coal
$0.05 - gas, combined cycle
$0.06 - nuclear
$0.06 - geothermal, hydrothermal vent
$0.06 - wind, onshore
$0.07 - gas, combustion
$0.08 - gasified coal
$0.10 - wind, offshore
$0.10 - geothermal, blind (i.e. no natural surface vent)
$0.20 - solar, concentrated
$0.28 - solar, PV

Geothermal has been in the range of coal/nuclear if there's a natural hydrothermal vent. But if you have to drill it ends up costing nearly twice as much. Wind is just starting to become competitive (it was around $0.10 per kWh 7 years ago). Solar unfortunately is still 20+ years away. It's really only viable on a commercial scale in remote locations with high alternative electricity prices (e.g. Hawaii, where they burn oil shipped in from the mainland so electricity is $0.30-$0.50 per kWh). In areas with lower electricity prices, solar is pretty much a publicity stunt.

about a week ago

To Fight $5.2B In Identity Theft, IRS May Need To Change the Way You File Taxes

Solandri Re:Solution (406 comments)

Interestingly, before the oft-questioned "passage" of the 16th Amendment, "labor given in exchange for payment" was just that; income was what a business earned as a result of selling a product or service.

We're wasting billions of dollars because of people like you, trying to maintain the illusion that taxing businesses is somehow different from (morally superior to) taxing individuals.

It doesn't matter which one you tax - the money is always coming from The People. A business is just a group of people who've decided to work together. If you tax a business, that doesn't magically spare people from the taxes. The business has to get that money from somewhere - it gets it by raising prices for customers, and/or reducing employee wages.

Income (whether by individuals or businesses) is just a manifestation of productivity. And the only source of productivity is people - a business is non-functional if you remove the people. Taxes are simply a way to divert some of the fruits of that productivity to the government.

So it doesn't matter whether you use an income tax, a sales tax, or a corporate tax - they all have the exact same effect. Some of the fruits of people's productivity get shifted from their control to the government's. If you use an income tax, their take-home pay is reduced. If you use a sales tax, their purchasing power is reduced, which is mathematically equivalent to reducing their take-home pay. If you use a business tax and the business pays for it by reducing wages, then take-home pay is reduced again. If you use a business tax and the business pays for it by raising prices, purchasing power is reduced again. It all does the same thing.

There are incidental effects of taxation which can justify certain taxes outside of immediate revenue-generation. e.g. Property taxes encourage people to find a productive use for land, or sell it to someone who will. Without them, you end up with people hanging on to their strawberry farm in the middle of an urban growth area, waiting for the value to increase when the land could be put to much better use right now. Value added taxes discourage middlemen from buying resources and supplies simply to flip them. etc.

But these benefits are orthogonal to immediate government revenue. They don't change the fact that taxing anything means you're reducing how much of The People's productivity is under their direct control, regardless of what exactly you're taxing. So the most efficient strategy is to come up with the simplest and easiest to enforce tax and use that for the bulk of your government revenue. Whether that's an income tax, a sales tax, a corporate tax, or some other tax is irrelevant.

about a week ago

Nvidia Sinks Moon Landing Hoax Using Virtual Light

Solandri Re:Is it healthy or unhealthy for society to have (275 comments)

I'm just wondering if when a society has conspiracy theorists speaking out freely, the 'tin hat' crowd, is that the sign of a healthy society or not.

It's bad I suppose when conspiracy theorists are flat out wrong, but would a repressive government try to silence them or do repressive governments only bother suppressing people who are telling the Truth?

Does it do harm in that when somebody really finds something bad going on people will tend to disbelieve them because of all the flakos (sort of like crying wolf too many times)?

There's a subtle distinction here that gets lost in our modern society (mainly by the media) which tends to look only at results while ignoring the process to get those results.

Skepticism is healthy. If you're skeptical that NASA landed on the moon, then by all means you should be free to ask questions, do tests and experiments to determine the truth of the matter to your satisfaction. Implicit in this is keeping an open mind that your skepticism may be wrong.

Where it crosses the line into conspiracy theory is when you assume a certain conclusion, and only accept supporting evidence, while ignoring evidence to the contrary, That's unhealthy.

Unfortunately, pure skepticism is impractical and an evolutionary dead-end. If you were skeptical about everything, you wouldn't be able to function. You'd second-guess every decision you made, every thing you thought you saw, anything you were told. Is the news really broadcasting the Presidential debate, or are they slyly editing it to make their preferred candidate sound better? Is it really safe to change lanes, or did you miss a car in the other lane somehow? Did you read what I just wrote accurately, or did you misread and so you should go back and re-read it to make sure? At some point you have to make the leap from 90%-99% certainty to assuming it's 100% just so you can make a decision and choose an action. That's why engineers tend to be more religious than scientists - engineers are forced to make design decisions in the face of incomplete data all the time, while scientists by the nature of their work are expressly forbidden from doing so. So engineers are more comfortable making that "leap of faith." But as long as you understand you're making that "leap of faith" for the purpose of making a timely decision, you're not into conspiracy theory territory yet. You only cross that line when you refuse to revisit your conclusion in the face of contrary evidence.

And no, conspiracy theorists are not always wrong. They were right about global warming. I'd estimate that probably a third to half the people who believe in global warming do so because they want it to be true for environmental protection reasons. The data had nothing to do with it aside from affirming a conclusion that they'd already reached and were going to stick to no matter what the data said. i.e. They are conspiracy theorists. In that respect I don't consider many global warming proponents to be any different from global warming deniers. The time just happened to match up with the hands of their broken clock. If it had turned out that the Earth was cooling and we needed to pump industrial quantities of CO2 into the atmosphere to forestall another ice age, they would've been the deniers, not the other way around.

tl;dr - Skepticism is better, but you need some conspiracy theory-like tendencies in order to function.

about a week ago

Ask Slashdot: Who Should Pay Costs To Attend Conferences?

Solandri Re:Your employer (182 comments)

It's hard to tell from the summary (probably intentionally so), but it sounds like it's the author who wants to go to the conference - it's not something his employer wants to send him to. There happens to be training he can take there, and the employer is willing to foot the bill on that. And the author is using that to falsely imply that he's going to the conference to get the training, therefore his employer should pay for the conference as well.

If the employer wanted him to go to the conference, they would be sending him there and paying for it. If they wanted him to get training, they would be sending him to training and paying for it. If they wanted him to get training at the conference, they would be sending him to both and paying for both. Frankly, I think his employer is being mighty generous offering to pay for the training he's taking because he wants to, not because they required or requested it.

If the author feels this conference is critical to his ability to do his job, and his employer is not willing to send him there, then he needs to do a better job explaining (to his employer, not to us) why it's so important for him to go to this conference. It's common for a particular employee to be the company's subject matter expert in a particular field, and a good manager will know to trust the employee's judgment in those cases. If author has not made such explanations before, try breaking it down into monetary cost/benefit. Business-types love that. e.g. Show why the tech will become of key importance in the future, lay out the cost to hire an outside consultant expert in the tech, and compare it to the cost of paying for your conference, travel, and training to make you expert in the tech.

about two weeks ago

NVIDIA Launches Maxwell-Based GeForce GTX 980 and GeForce GTX 970 GPUs

Solandri Still 28nm (125 comments)

At this point I think it's safe to write off TSMC's 20nm fab process. It's not gonna happen, with signs pointing to development being shifted to 16nm instead.

A lot of what you see going on in the GPU and mobile front is being dictated by the failure of TSMC and other fabs to transition to 20nm for processors (memory is a lot easier and reached 16nm in 2013). Intel made the transition from 32nm to 22nm last year with Haswell and Bay Trail. The other fabs were supposed to leapfrog Intel by going from 28nm to 20nm this year. They haven't, which is what's allowed Intel to produce Atom SoCs with power usage approaching that of ARM SoCs. ARM has the lower power tech, but Intel's smaller lithography is mostly wiping out that advantage. If you see Intel successfully make the transition to 14nm in 2015 while the other fabs can't get 16nm to work, things are going to get really interesting on the mobile SoC front..

The GPU front is bleaker. Both nVidia and AMD use third party fabs like TSMC, so there's no competitive advantage to be had. We've just had to suffer with stagnating product lines and slow product releases because the expected lower power consumption in GPUs from 20nm didn't happen in 2014.

about two weeks ago

Scotland Votes No To Independence

Solandri Re:Everyone loses (474 comments)

As I said, I've been here for a decade now, and I work for a big company with great perks. It's been good for me, but now that I have a kid, the school-shootings thing is getting more and more worrisome. There's literally nothing I can do to prevent some moron raiding his mother's arsenal and killing my kid if that's how he wants to end his life.

Why this obsession with school shootings? You do realize your kid is far more likely to be murdered outside of school than in school? "Homicide is the second leading cause of death among youth aged 5-18. Data from this study indicate that between 1% and 2% of these deaths happen on school grounds or on the way to or from school." So 98%-99% of homicides of school-aged children happen outside of school. i.e. The place where your kids are safest by far from being shot or killed is in school.

If you look at the chart in the above link, on average fewer than 20 students are murdered each year in school shootings. If you look at causes of death, among 5-14 year olds (page 2), the #15 cause of death kills 18 per year, indicating school shootings doesn't even rank in the top 15. For age 15-24 (high school-college), the #15 cause kills 99 per year, so school shootings probably doesn't even make the top 20 or 30. By far the #1 killer of student-aged children is accidents - outnumbering homicides by nearly an order of magnitude, and school shootings by two orders of magnitude.

It's the media which has a morbid obsession with school shootings, causing them to devote wildly disproportionate amounts of coverage to it relative to other dangers and risks faced by school-aged children. Don't buy into it. Parents' fear of school shootings is completely irrational, just like fear of flying (which is also fed by the media's disproportionate coverage of plane crashes), or child abduction by a stranger (which is the rarest form of kidnapping, and also fed by the media's... well you get the picture).

about two weeks ago

Study Finds Link Between Artificial Sweeteners and Glucose Intolerance

Solandri Re:I know this is going to sound crazy... (294 comments)

The thing is, I don't think most people realize just how much sugar is in sweetened beverages. When you eat a slice of pie or a scoop of ice cream, your brain quantifies it as a discrete amount of sustenance and naturally limits your intake. But for some reason when you're drinking, people rationalize that "it's mostly water" and overconsume. I didn't realize it myself until I ordered a regular iced tea because the restaurant didn't carry sweetened, and tried to sweeten it myself to taste. After 4 packets of sugar went in and it still tasted bland, I realized that there's a heckuva lot more sugar in these sweetened drinks than I'd thought.

about two weeks ago

Snowden's Leaks Didn't Help Terrorists

Solandri Re:The sad part is... (183 comments)

Both sides are likely lying.

You don't acknowledge damage when you're in a state of combat. That's just giving away intelligence to the enemy for free. It's like when CBS reported the exact location of Iraq's first scud missile strike against Israel. Why would you freely give the enemy information verifying their attack worked and thus help them improve future attacks? That's just stupid.

The people claiming Snowden's disclosures have compromised intelligence gathering methods are either committing treason by confirming to the enemy that their obfuscation methods are working, or know that it hasn't and are lying through their teeth to misdirect the enemy, or don't know anything and are lying by pretending to know in order to score political points.

Likewise, the people claiming Snowden's disclosures haven't compromised intelligence are either committing treason by confirming to the enemy that their obfuscation methods have been unsuccessful and they need to try something else, or know that it has a has and are lying through their teeth to misdirect the enemy, or don't know anything and are lying by pretending to know in order to score political points.

I tend to believe anybody who really knows is also smart enough to know not to reveal that info (and not commit treason) and are keeping their mouth shut. And so anybody who's claiming "with certainty" one way or the other is likely lying.

about two weeks ago

Apple Will No Longer Unlock Most iPhones, iPads For Police

Solandri That doesn't mean this is a bad move (504 comments)

As much as the government wants these powers, and wants them in secret, this is really a policy decision which needs to be made by the citizens. They need to decide if off-the-shelf products should provide end-level encryption by default, or if the government should always have a back-door into all encrypted products. Not politicians, not the police, and certainly not secret government courts. Society at large needs to decide which is more important - personal privacy, or the government's ability to obtain evidence of laws being broken in communications mediums and storage devices.

This move by Apple puts the debate squarely in the public's eye, instead of hidden in esoteric cryptography forums and secret government courts.

about two weeks ago

Apple Will No Longer Unlock Most iPhones, iPads For Police

Solandri Re:So everything is protected by a 4 digit passcod (504 comments)

Standard data forensics procedure is to write-protect any storage device which contains evidence, copy it bit-for-bit, and do all the decrypting and data analysis from the copy. The 10-try limit may protect your data from a random thief who lifts your phone, but the only way it's going to protect you from the government or any other technically-capable hacker is if Apple baked the limit into the flash memory-reading hardware.

And there's always this.

about two weeks ago

How Flickr Is Courting the Next Generation of Photographers

Solandri Re:...the best photographers were older people... (97 comments)

As someone who learned photography "the old way" (film, darkroom, nasty chemicals), there is something to what both of you have to say. My rate of "keepers" in the film days was about 1 shot per roll (1 in 36). My rate of "keepers" in digital is about 1 in 100. So clearly I'm not being as careful to compose the shot perfectly. And I'm definitely taking multiple shots on many occasions with the hope that one will be good.

But my rate of "keepers" per trip has skyrocketed. With film I'd be happy if I managed just 2-3 keepers from a trip. With digital I expect 5+ and am disappointed if I don't get 10. This is because I shoot a lot more pictures with digital than I ever shot with film. The cost of the professional film I used + developing meant I was paying $0.50-$1 per shot. That put a serious damper on photography. I think the most film I ever shot on a trip was 12 rolls (432 pictures) over 4 weeks, or an average of 15 shots a day. With digital I'll take 2000-3000 shots on a similar trip, or 70-110 shots a day.

FWIW, the rate of keepers seems to be consistent (between 1 in 50 to 1 in 100) among both amateurs and professionals. i.e. The pro photographers aren't getting those great shots by snapping a few pictures. National Geographic did an article on how they make articles. The photographer shot over 5000 photos (on film!) to arrive at the 8 photos used in the article.

Which approach is better? Hard to tell. Though truth be told, equipment actually doesn't matter. National Geographic photographers have intentionally gone on trips equipped with nothing more than an iPhone and still take stunning photos using nothing more than the default camera app.

Equipment does matter. Photography isn't just a matter of seeing something cool and snapping a picture of it. Wide-angles can give you unusual perspectives. Better equipment gives you access to different capabilities. Telephotos allow you to compress perspective, as well as pick out distant subjects without having to run all over. A wider aperture lens can blur the backgrounds more in portraits. Flash exposure compensation can allow you to use a flash, but make the picture look like it was shot without a flash. Zooming during the exposure followed by a flash can create an impressionistic effect which emphasizes the subject. etc.

I recently drove some European friends to San Francisco. Unfortunately we arrived right around dusk, and they weren't able to get a decent shot of themselves with the Golden Gate Bridge in the background. I simply borrowed one of their DSLRs, mounted it on a tripod, put it in aperture priority mode, turned the flash on with FEC dialed to about -1.0, and told them to stand perfectly still for a few seconds. When you do that, the DSLR automatically adjusts the exposure time for the background, but exposes the foreground by modulating the flash. The result was a perfect image of the bridge and city lights in the background, with my friends perfectly exposed in the foreground.

That was GP's point - that better equipment gives you access to more options and different things you can do to take different and better pictures. While it's certainly possible to take good photos with a smartphone, the number of different types of good photos you can take is considerably less than with a DSLR and good lenses. OP misinterpreted GP's post as a film vs digital thing.

about two weeks ago



Students figure out how to unlock school-issued iPads

Solandri Solandri writes  |  1 year,4 days

Solandri (704621) writes "The Los Angeles Times reports that the LA Unified School District's plans to assign an iPad to every student in the district are on hold after students figured out how to unlock the iPads. Once unlocked, the iPads can be used for decidedly non-academic activities such as surfing the web and accessing social media sites. According to students, unlocking the devices is simple — just delete your personal profile info."


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