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Comment: Reply to Comment (Score 2) 85

The paper does explain these limitations and it would be wrong to assume that this means we can see/photograph through fog, skin, clouds... But a semiconductor laser can have a spacial coherence long enough to do holography so if they said the source was a laser and non-conherent narroband, I'll give them the benefit of the doubt and assume they did something to destroy the laser coherence. Spinning frosted glass beam interrupters and other techniques are often used to despeckle laser light where it interferes with the laser's intended use.

Speckle does occur with non laser light sources but it isn't usually as strong because of the shorter coherence length. Go outside on a sunny day and look at your fingernails or a piece of black anodized metal, you may see the effect of white light speckle interference. The really amazing part of this technique is that they did it with such a low-res camera. While 42 Megapixels seems like ridiculous overkill for a phone camera, it doesn't hold a candle to the typical spacial resolutions approaching 400 Gigapixels for holography film. Extend and expand the technique into higher resolutions, illuminate with coherent laser light sources and it will be a valuable technique for laser imaging as well as other things. What else has point light sources against a dark sky and obscuring translucent material? The starry night sky. I knew the day would come when finally astronomers can have their cloud filter!

Comment: Re:Poor management (Score 1) 423

by An dochasac (#46406749) Attached to: RadioShack To Close 1,100 Stores

...Every employee had to take about 15 multiple choice tests. But every store had cheat sheets and no one really learned anything.... If an employee didn't ask every customer about a cell phone AND a satellite dish they were fired. Even before that turnover was like a fast food place.

Were you at Radioshack when they became one of the first and last private US employers to require polygraph test as a condition for employment? Yes there is a reason Snowden never worked at Radio Shack. Whoever managed that company during the 90s should be working for Vladmir Putin right now.

Comment: Re:Stop Being Something Your Not (Score 1) 423

by An dochasac (#46406685) Attached to: RadioShack To Close 1,100 Stores

They had a commercial during the SuperBowl with 10,000 80's superstars. Getting into futuristic stuff like Raspberry Pi's, Arduinos and 3D printers is a great idea, but it would have been nice to hear about that during the commercial rather than see Hulk Hogan get into a DeLorean. Instead, I just found out about it on this thread.

And they need to stop the price gouging. If a Pi is $35 online, there's no way I should pay more than $69.99 no matter how much they are helping me. Anything more is robbery.

Radio Shack spent too much on their Superbowl ads and not enough on training staff. I live overseas so I visit RS maybe once a year. When I heard they were getting back to their hobbiest roots I almost forgave them for diving all of the independent radio parts shops out of business such as my former employer. I asked their employees about arduinos and other microcontrollers, they'd never heard of them. So I took them to the back of their store and showed them where they were. I asked about UV LEDs. They found me an IR LED, close but no cigar. I dug through a couple more drawers and showed them the UV one. Something like $4 for one LED, only about 5000% markup from the low-quanity price at Digi-key and Farnell, 10000% above what you'd get them delivered from Chinese online shops if you're willing to wait a month but yes if I needed it then and there, there it was. If only their staff knew what they had and knew how it could be used so they could help customers and get customers interested in buying more.

RS management, if you're listening, hire hobbiests and train the rest of your staff in Linux, electronics repair, arduino, PIC. Sift through the millions of wholesale electronics products and sell only the most open, well-documented and hackable products. Sell Arduinos, Pics, Pis, Canon (CHDK) capable cameras, software defined radio chips. Set aside a Makerspace/repair cafe in your store. Install 3D printers and create online portal for shared 3D designs, arduino sketches, Raspberry Pi and Linux. Buy a small wave solderer and train staff on how to rejuvenate the millions of video games, laptops and tablets whose GPUs have unsoldered themselves. Make deals with Amazon, alibaba, ebay, dx, farnell. You have a &(*@ load of retail space, they have the commodity components and proprietary batteries. Make your stores retail portals with staff to explain, upsell on installation and help. Clear your in-store warehouses to make room for deliveries.
You're welcome!

...or am I bluffing?

Comment: Re:two words (Score 2) 423

by An dochasac (#46406609) Attached to: RadioShack To Close 1,100 Stores

...The last time I was in Radio Shack two months ago, they still had blank VHS tapes on the shelf.

What! No blank Betamax L-750s?

I won't miss those expensive, leaky Radio Shack batteries, guaranteed to destroy whatever overpriced electronic gadget you bought at Radio Shack last month. Even Apple's welded-in iPhone batteries can't match that level of planned obsolescence.

Comment: Re:So what will end up happening is the states tha (Score 1) 597

by An dochasac (#46248265) Attached to: Financing College With a Tax On All Graduates

The real problem is the whole student loan system. Since most people are paying for college with unlimited-balance, government-guaranteed loans, colleges can charge whatever the hell they want and they know that everyone can afford it and they always get paid. Why does the cost of tuition rise so much faster than inflation? Because colleges suffer no consequences for raising tuition.

If you took away the unlimited aspect or the government-guarantee aspect, you'd see tuitions stabilize right quick. If Uncle Sam (or I guess Aunt Sallie, in this case) said, "Colleges, go ahead and charge whatever the hell you want, but we're only giving each student $15k/yr in loans, indexed to inflation," you'd see colleges implementing some cost controls. Likewise, if Sallie Mae said, "Colleges, we pay you when the student pays us, so better make things affordable, hmm?" same thing would happen.

But no, we have a bubble like the real estate bubble because everybody's buying with other people's money, so nobody cares what it costs.

Mod parent up. US higher education debt now totals more than a trillion dollars. And it's becoming more obvious with each passing semester that students are reliving the history of the dot com and property bubbles. Take something of value, build a story around it that exaggerates its fiscal value, find some sucker to finance it (US taxpayers are born every minute.) This proposed fix won't help. There are too many ways to game the system. We've already turned our state-funded universities into glorified trade schools, funneling most students into accounting, MBA or whatever students counselors perceive to have the shortest term ROI. Basic research suffers and paradoxically unemployable degrees are on the rise. Universities win as long as there is a warm body in a classroom seat. The proposed system might help in the short term by forcing the burden of unraveling this mess onto the most educated population, but in the long term it will punish higher education, reward those horribly narrow certificate factories, give further advantage to PhDs in India and China and force even more of our best and brightest to leave the country.

Comment: Re:education (Score 1) 306

by An dochasac (#46100487) Attached to: US Forces Coursera To Ban Students From Cuba, Iran, Sudan, and Syria

Not joking, sarcastic. Because as you point out, this ban on education only helps to further solidify the positions of the dictators in the countries that the US has an embargo against. An embargo that was (presumably) put in place to try and get the dictators to change their ways about something. And here the US is, banning something that could get the populations of those countries to force the dictators into that change.

Because the 54 year-old embargo against Cuba was so effective at turning the Cuban people against Castro^H^H^H^H the US.

Makes you wonder what the real purpose of those embargoes is.

The black marketeers love it and it keeps up the price of fake Cuban cigars.

Comment: Re:Not as bad as the reviews made it seem (Score 1) 178

by An dochasac (#46091395) Attached to: IBM's PC Junior Turns 30, Too

The keyboard was horrible, yes, but that was fixed within months (I think people could swap the keyboards for free?).

As proof that computer companies have always blindly followed in the footsteps of other computer companies and repeated their UI mistakes, the following computers preceded PCjr's bad keyboard design:

When the PC/jr came out, the Commodore 64, Commodore Vic 20, Apple II series, Texas Instruments and Mac computers all had decent keyboards but IBM decided to reinvent keyboards again.

Comment: A fiscal iron curtain for 46 million Americans (Score 1) 337

by An dochasac (#46079333) Attached to: Is the West Building Its Own Iron Curtain?

I've been through a passport application and two renewals. All it took was filling out the form and sending it in with a couple of pictures. I never needed to ask permission to travel, and all three times I sent in paperwork, I did not have pending travel. I am not sure what you mean by "get permission to travel." From whom are you asking permission and why?

I live abroad and have been through several passport applications and renewals. But for many of my American friends and family, the cost is prohibitive. They will never be able to visit me and they can no longer visit other parts of North America.

The cost of an adult US passport book and is currently $140 plus a $25 "execution fee." Add the photo, paperwork and postage and you're getting near $200 add another $150 for a file search if the person can't produce evidence of citizenship. Minors (under 16) are $95+$25. So for a family of four living in, say Niagara Falls, NY or Detroit, Michigan it can range from $570 to $1170 for the right to cross over to a better neighborhood on the Canadian side. You might say, "What's $570, that's only the cost of an iPad or iPhone?" But for many, this is two paychecks, a month's rent, the family car or a medical bill for a minor visit to a medical center. The US has an iron-curtain but it applies to the 9.9% of white Americans, 12.1% of Asian-Americans, 26.6% of Hispanic-Americans and 27.4% of Black-Americans who live below the poverty line.

Comment: Dry ice pop rocks (Score 2) 180

by An dochasac (#46026103) Attached to: More Details About Mars Mystery Rock

A bit of dry ice forms in a crack in a stone and stays below freezing for a day or a million years before a rover tyre moves some soil and exposes it to the heat of the sun. The dry ice sublimates but instead of earth water's slow process of expanding and cracking a rock, sublimated dry ice occasionally pops a rock shard quite a long distance. Like pop-rocks.

Pop rock manufacture (from Wikipedia): The candy is made by mixing its ingredients and heating them until they melt into a syrup, then exposing the mixture to pressurized carbon dioxide gas (about 600 pounds per square inch or 40 bar) and allowing it to cool. The process causes tiny high-pressure bubbles to be trapped inside the candy.

Comment: Poprocks on mars (Score 1) 112

by An dochasac (#45997191) Attached to: Mystery Rock 'Appears' In Front of Mars Rover
This may be another example of where our geocentric understaning of landscape geology misleads us. Perchlorate-rich soil under carbon-dioxide rich low atmospheric pressure, thermal tides, carbon dioxide ice... What would happen if a bit of CO2 froze inside a rock or in a pocket beneath a stone and eventually got up to its sublimation temperature? Sometimes it would vaporize with enough force to pop the rock somewhere else. What if the perchlorate-water reaction that caused so much excitement with the Viking landers happened naturally due to condensed water vapor? Might that sometimes cause internal pressures within rocks and cause them to fragment?

Comment: Re:Seeing that (Score 2) 118

by An dochasac (#45965257) Attached to: Target Hackers Have More Data Than They Can Sell
This is similar to what Northern Irish banks did after the Northern bank robbery got away with 26 million pounds sterling a few years ago. They recalled all of the northern Irish cash. Rumor is that a member of the political wing of the old IRA was spotted burning cash in his back garden. This becomes much easier with credit cards and digital currency but isn't too difficult in a small country where banks are able to issue individually identifiable notes (much as the US once did.)

Comment: ROW MOOC vs US:twice the education, 1/3 the price (Score 1) 51

by An dochasac (#45915409) Attached to: MIT Begins Offering For-Pay MOOC In Big Data
US brick and mortar universities such as MIT have a captive consumer-base. They form a powerful oligopoly in a land where fewer than 50% of the citizens have passports and even fewer are aware that they are paying 2 to 3 times as much for their community college or technical institute than British students pay for Oxford medical school. While it is true that US brick and mortar universities do provide services that can't be found online. For example, the country-club gymnasiums and dormitories, sports, entertainment, party lifestyle and physical networking with the wealthy. But for those who value other university products (e.g. education), MOOC schools can work. The interesting thing with MOOC schools is that US for profit universities are on a level playing field with well-established distance learning universities in the UK, South Africa and elsewhere.

Comment: Soldiers Grove, WI relocated and solarized in 1979 (Score 3, Informative) 172

by An dochasac (#45912949) Attached to: How Do You Move a City?
This has been done before. Soldgier's Grove Wisconsin was moved due to flooding by the Kickapoo river. One interesting outcome is that this happened in 1979 during a time of rapidly ising energy prices so the new business district was designed to be heated by solar energy. Several million residents who lived in towns near China's 3-gorges dam were also relocated.

Comment: Amiga Digiview by NewTek (Score 1) 124

by An dochasac (#45906289) Attached to: How One Photographer Is Hacking the Concept of Time

...Heck, you could even do this in post-processing using a normal 2-D camera that's capturing a movie. Just snag a single column from successive frames and stack them into a single picture. Sure, your frame rate will be limited, but it's technically feasible, especially if the 2-D sensors allow for windowing to increase frame rate.

AFAIK this single column capture is very close to what NewTek's Digiview did on the Amiga computer and it was done that way because that was the cheapest, simplest way to digitize an NTSC/PAL frame on a slow computer which just happened to have a clock rate synchronized to the NTSC, PAL or SECAM video refresh rate.

Magyar's technique is more sophisticated but if you panned a tripod at the same rate as someone walking past a video camera during a Digiview capture, you ended up with a space/time distortion somewhere between Magyar's and the motion blur you'd get with an analogue camera. We had as much fun playing with this aspect of Digiview as we had making "proper" still digitizations which required keeping the camera and subject absolutely still while you swapped in Red, Green and Blue filters. A turned head was stretched out into a weird cylinder with hair and chin in place but ears and eyes elongated horizontally. We also found that it it was possible to create anaglyph 3D images by moving the camera horizontally during exposure.

Space

Is Europa Too Prickly To Land On? 140

Posted by samzenpus
from the watch-your-step dept.
astroengine writes "A deadly bed of icy javelins — known as penitentes — could be awaiting any spacecraft that tries to land on some parts of the ice-covered world Europa, say researchers who have carefully modeled the ice processes at work on parts of the Jovian moon to detect features beyond the current low resolution images. If the prediction of long vertical blades of ice is correct, it will not only help engineers design a lander to tame or avoid the sabers, but also help explain a couple of nagging mysteries about the strange moon. 'This is a game changer,' said planetary scientist Don Blankenship of the University of Texas in Austin. Blankenship has been involved in NASA's planning process for sending a reconnaissance spacecraft and eventually a lander to Europa."

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