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Comments

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MIT Designs Tsunami Proof Floating Nuclear Reactor

necro81 Re:Those also sink (216 comments)

Subs are designed to sink.

Its part of their mission.

Don't be a dolt. Submarines are designed to dive, not sink. Sinking is, more or less, a one-way trip, whereas diving is reversible. If subs sink, they and their entire crew are lost.

Since you've never been in a submarine (your post makes that obvious), I'll bet you've at least seen a movie or two with a submarine in it. When it's time for the boat to go under the water, the captain says "Diving Stations!" "Make ready to dive!" or simply "Dive! Dive!"? If you replace "dive" with "sink" in the previous sentence, it just doesn't sound right.

3 days ago
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MIT Designs Tsunami Proof Floating Nuclear Reactor

necro81 Re:wonder bout... (216 comments)

If you build it at an appropriate depth, you don't need to worry as much about a pressure vessel, because the ambient pressure outside would equal the pressure inside. In other words, you use the pressure of the water column to pressurize the reactor.

Even better, situate it just a bit deeper and allow that pressure differential to assist in moving fresh coolant into the reactor.

3 days ago
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Ask Slashdot: What Good Print Media Is Left?

necro81 Re:IEEE Spectrum, much more than electronics (285 comments)

I used to receive Spectrum until I determined that my IEEE membership wasn't doing me much good. Thankfully, all of Spectrum's content is available on their website. It's not the same as a print magazine, but I still check it out.

3 days ago
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Ask Slashdot: What Good Print Media Is Left?

necro81 Re:Make and W.I.R.E.D. (285 comments)

I still have a subscription to WIRED because I still find some new trends in consumer tech there. Other times they'll report on something and I'll think to myself "Damn, I heard about that through IEEE Spectrum, Make:, or somewhere online months or years ago. Where the hell have these guys been?"

About every other month one of their long-form articles will genuinely satisfy. I highly recommend the 20th anniversary compendium of their best long-form stuff.

I will note, however, that the satisfying long-form stuff is never their cover article. The development of the cover article, and accompanying eye-catching cover, usually goes like this:

1) take some topic that has been floating around the zeitgeist for a bit. For example - "The capabilities of 3D printers have been improving for years, while costs have been going down"
2) throw one or two contemporary data points at it, "The original RepRap was a piece of shit, and cost $$$ plus a year's worth of tinkering to build and get running properly. The latest $Machine produces passably good knicknacks, works out of the box (mostly), and only costs $$."
3) take it to its most illogical, hyperbolic, and unsupported conclusion. "Soon we will never go shopping, we will produce all consumer goods in our own basement for pennies!"
4) find a celebrity to put on the cover. Anyone, really, will do.
5) give the Art department a hit of LSD and Red Bull, then create the cover from (3) and (4),
6) ???,
7) Profit!

So, yes, I find WIRED to have enough useful and interesting content to continue paying a subscription price for it. But I open each issue with modest expectations, and drop it off at the gym for someone else to read as soon as I'm done with it.

3 days ago
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NASA To Send SpaceX Resupply Capsule To ISS Despite Technical Problems

necro81 Re:Well done (71 comments)

The DMZ for New Jersey has been 500% better ever since privatization

So many potential jokes... where to begin?

"The NJ DMZ: blocking border crossings at 1/5th the price since 1995!"

"The NJ DMZ: we'll blow you up, but won't break the bank!"

"I thought all of NJ was a demilitarized zone!"

Anyone else?

about a week ago
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NASA To Send SpaceX Resupply Capsule To ISS Despite Technical Problems

necro81 Re:They like hard western cash. (71 comments)

American flights, Russian flights ... all made in Taiwan! [source]

about a week ago
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NASA To Send SpaceX Resupply Capsule To ISS Despite Technical Problems

necro81 Re:Open the pod bay door HAL (71 comments)

presumably, in the event of a failure, they could just "park" the Dragon a convenient orbit

It's an operational hassle, to be sure, but I wonder if part of Elon Musk is hoping for just that opportunity. The Dragon capsule gets more flight time, and the chance to demonstrate significant orbital changes, start/restart of the engines - all on NASA's dime!

about a week ago
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NASA Setting Up $250,000 Mars Lander Competition

necro81 Re:Horizontal (44 comments)

So the two issues (the landing position and launch position) are disjoint (only the lander has to land in a mostly upright position)

So the lander - a launch platform - is going to land on the surface of Mars with a long, horizontal rocket laying across it? That was the part that didn't make much sense to me.

about two weeks ago
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NASA Setting Up $250,000 Mars Lander Competition

necro81 Horizontal (44 comments)

The Challenge would award prizes for successful demonstration of an end-to-end autonomous operation to sequentially accomplish the following tasks: picking up the sample, inserting the sample into a single stage rocket in a horizontal position, erecting the rocket, launching the rocket to an altitude not less than 800m, deploying a sample container with the cache internally sealed and landing the container at less than 6m/s terminal velocity.

I wonder why the rocket starts off horizontal. For an actual sample return mission, do they intend to land the return rocket horizontally? I always figured that the return rocket would be upright when it sets down or gets placed on the surface, like the Delta Clipper or Grasshopper.

about two weeks ago
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Land Rover Demos "Transparent Hood"

necro81 Re:Cue the naysayers... (172 comments)

But I'm sure slashdot naysayers will find an angle anyway

Camera...angle...

I see what you did there.

about two weeks ago
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Navy Creates Fuel From Seawater

necro81 Re:Energy (256 comments)

but I don't see this supplanting the fossil fuels any time soon

Maybe yes, maybe no. We're probably going to continue using liquid fuels for a long time. Some folks talk about the hydrogen economy being the replacement for hydrocarbons, but I've often wondered why. Hydrogen is a tricky fuel, starting from its relatively inefficient creation, through the difficulties in storage, transportation, distribution, to tricky bit of transferring and storing it in a vehicle tor provide sufficient usable range. If you've got the technology for manufacturing huge quantities of hydrogen, why not go one step further and create low weight hydrocarbons (methane, ethane, etc)? Those are much more energy dense, easier to transport and store, and there's already an extensive infrastructure in place.

about two weeks ago
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The Problem With Congress's Scientific Illiterates

necro81 Re:Don't bother. (509 comments)

I've already heard three rants about the stupid, stupid government designing forms that the smart engineer can't use

What, that's not rant-worthy? I know the tax code is stupendously complex and all, but one should not have to be a professionally trained tax-preparer to be able to do an honest job of it.

Regarding the rest of the behavior you describe - yeah, that's just plain asking for trouble.

about two weeks ago
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The Problem With Congress's Scientific Illiterates

necro81 Re:Don't bother. (509 comments)

That may be, but for the sake of humility, I try to recognize my own ignorance. I do not bloviate about how fantastically wonderful my ignorance is, nor belittle the opinion of people who actually are experts. Not about things that actually matter - ya know, important stuff like life and death and the survival of nations. Then again, I'm not a self-serving politician in a place of power. That's why this kind of behavior from politicians drives me bonkers. Their celebrated ignorance and obstinance in the face of established theory isn't just some game - even if they are playing at one - this will have real, serious, and mostly bad consequences that they couldn't care less about.

about two weeks ago
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Oxford Internet Institute Creates Internet "Tube" Map

necro81 Re:Surveillance + Imprisonment != Censorship? (56 comments)

Try living in mainland China for a few years, or one of several countries in the Middle East, or The Sovi...er, I mean Russia, and then come back to the USA and talk about the relative levels of censorship.

about two weeks ago
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Will Cameras Replace Sideview Mirrors On Cars In 2018?

necro81 Re:nope! (496 comments)

You can point a camera anywhere you want

What is more, you can do a variety of optical manipulations with a camera that you can't with a mirror. For instance: have a wider, fisheye view for certain driving circumstances, or a narrower, more directional view for others.

Cameras are also useful inputs for various vehicle systems - navigation, active cruise control, crash avoidance, etc. Right now these rely on a different set of cameras, laser rangefinders, radar, etc. These sensors are extra components. If most cars have cameras already, these features are easy to implement

about three weeks ago
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Tesla Model S Gets Titanium Underbody Shield, Aluminum Deflector Plates

necro81 Re:sky should be the limit... (314 comments)

Because carbon fiber is not a particularly effective material for armor and impact resistance?

about three weeks ago
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Tesla Model S Gets Titanium Underbody Shield, Aluminum Deflector Plates

necro81 Re:Sounds like (314 comments)

Well, an 18650 Li-Ion cell, of which the Model S has thousands of, is about the right size and shape for an armor-piercing round. (The 18 is "18 mm diameter", the 650 is "65.0 mm length".)

about three weeks ago
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Prototype Volvo Flywheel Tech Uses Car's Wasted Brake Energy

necro81 Re: Gyroscopic precession (262 comments)

The F-1 flywheel systems have a vertically oriented axis, so that the gyro forces are reduced.

The model demonstrated by Volvo has a horizontal axis, so the gyro forces will be greater and must be dealt with. Thankfully, it's pretty easy to quantify. If you get the flywheel spinning in the correct direction, you can even make the forces work in your favor to reduce roll during a turn.

about three weeks ago
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Facebook Buying Oculus VR For $2 Billion

necro81 Re:saw a picture on MarketWatch (535 comments)

if that thing were any bigger and heavier, it would need braces to your shoulders and hips. non-starter

Yes, because we all know that technology never evolves. This thing will always remain big and heavy, and no amount of Facebook money will ever allow for a rev 2.0 design that is smaller, lighter, more stylish, or more capable.

I mean, aren't you still sporting a cell phone like Gordon Gekko? Doesn't your laptop still weigh 25 pounds?

about three weeks ago

Submissions

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Megatons to Megawatts Program Comes to a Close

necro81 necro81 writes  |  about 3 months ago

necro81 (917438) writes "In the aftermath of the Cold War, the disintegrating Soviet Union had tens of thousands of nuclear weapons and tons of weapons-grade fissile material. In the economic and political turmoil, many feared that it would fall into unfriendly hands. However, thanks to the doggedness of an MIT professor, Dr. Thomas Neff, 500 metric tons of weapons grade material made its way into nuclear reactors in the United States through the Megatons to Megawatts program. During the program, about 10% of all electricity generated in the U.S came weapons once aimed at the country. Now, after nearly 20 years, the program is coming to an end as the final shipment of Soviet-era uranium, now nuclear fuel, arrived in Baltimore."
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Inventor of AK-47 Dies at 94

necro81 necro81 writes  |  about 4 months ago

necro81 (917438) writes "Lt. Gen. Mikhail T. Kalashnikov, an arms designer for the Soviet Union, creator of the AK-47, passed away today at age 94. Kalashnikov was born a peasant and entered the Soviet Army as a conscript. However, the self-taught tinkerer had an aptitude that took him far. The AK-47, his best-known creation, was praised for its reliability and low cost; attributes that have made it the most successful firearm ever, seeing use in homeland defense, rebellion, terrorism, and untold massacres. The inventor was himself ambivalent about the uses his creation had seen, but was nevertheless proud of his contribution to his country, where he is praised as a hero."
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Another Casualty of Typhoon Haiyan: Geothermal Power

necro81 necro81 writes  |  about 5 months ago

necro81 (917438) writes "Little known even in environmental circles is a renewable energy success story: five geothermal power plants on Leyte Island in the Philippines — each of which producing enough power for the entire island — that collectively produce more than 10% of the Philippines total electrical demand. From boreholes deep underground comes pressurized water heated to 280 Celcius. At the surface it flashes into steam, turning one set of turbines, then cools and contracts to spin a second set of turbines. The low-grade steam is then condensed back into water and reinjected into the bedrock. But Typhoon Haiyan destroyed the cooling towers, snapped transmission towers, and scattered the employees."
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MAVEN mission to Mars will proceed, despite shutdown

necro81 necro81 writes  |  about 7 months ago

necro81 (917438) writes "Due to the ongoing shutdown of the U.S. Government, NASA is largely grounded. This is bad for all kinds of reasons, but one particularly bad outcome would have been missing the launch window for the MAVEN spacecraft, due to launch 18 November. The next launch window would not have been until 2016. MAVEN, thankfully, has been given the go-ahead, in large part because this orbiter will serve as a vital communications link for the Opportunity and Curiosity rovers currently on the surface. Currently, these rovers are served by two aging orbiters: Mars Odyssey (launched 2001) and Mars Reconnaissance Orbiter (launched 2005). Maintaining communications with the rovers is considered essential, hence the preparations and launch will proceed. (NASA's official mission website is currently offline.)"
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MAVEN mission to Mars will proceed, despite shutdown

necro81 necro81 writes  |  about 7 months ago

necro81 (917438) writes "Due to the ongoing shutdown of the U.S. Government, NASA is largely grounded. This is bad for all kinds of reasons, but one particularly bad outcome would have been missing the launch window for the MAVEN spacecraft, due to launch 18 November. The next launch window would not have been until 2016. MAVEN, thankfully, has been given the go-ahead, in large part because this orbiter will serve as a vital communications link for the Opportunity and Curiosity rovers currently on the surface. Currently, these rovers are served by two aging orbiters: Mars Odyssey (launched 2001) and Mars Reconnaissance Orbiter (launched 2005). Maintaining communications with the rovers is considered essential, hence the preparations and launch will proceed. (NASA's official mission website is currently offline.)"
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Link Rot and the U.S. Supreme Court

necro81 necro81 writes  |  about 7 months ago

necro81 (917438) writes "Hyperlinks are not forever. Link rot occurs when a source you've linked to no longer exists — or worse, exists in a different state than when the link was originally made. Even permalinks aren't necessarily permanent if a domain goes silent or switches ownership. According to new research from Harvard Law, some 49% of hyperlinks in Supreme Court documents no longer point to the correct original content. A second studyon link rot from Yale stresses that for the Court footnotes, citations, parenthetical asides, and historical context mean as much as the text of an opinion itself, which makes link rot a threat to future scholarship."
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Apple's New TouchID - Breakthrough or Disaster?

necro81 necro81 writes  |  about 7 months ago

necro81 (917438) writes "Apple isn't the first company to integrate a fingerprint reader into a cellphone. But with the introduction of TouchID into the home button of the new iPhone 5S, Apple has thrust the technology front and center, and made a big gamble in the process. Will users accept it? Will other companies follow? What happens if the false positive/false negative rates are too high? Without an open and inspectable protocol, we have to take Apple at its word that the fingerprint data exist only in the sensor and the (local) processor; no APIs for third-party access have been announced. Is this an acceptable security model? If it's an awful model, is it at least better than the alternative (passcodes, or nothing at all)?"
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Transporting a 15-m, 600-ton Magnet Cross Country

necro81 necro81 writes  |  about 10 months ago

necro81 (917438) writes "Although its Tevatron particle accelerator has gone dark, Fermi Laboratory outside Chicago is still doing physics. A new experiment, called muon g-2 will investigate quantum mechanical behavior of the electron's heavier sibling: the muon. Fermi needs a large ring chamber to store the muons it produces and investigates, and it just so happens that Brookhaven National Laboratory outside NYC has one to spare. But how do you transport a delicate, 15-m diameter, 600-ton superconducting magnet halfway across the country? Very carefully."
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Fukushima cooling knocked offline by...a rat

necro81 necro81 writes  |  about a year ago

necro81 (917438) writes "The cooling system at the crippled Fukushima Dai-ichi nuclear power plant, responsible for keeping the spent fuel pools at an appropriate temperature, lost power early on March 18th. During the blackout, the temperature in the spent fuel pools gradually increased, although TEPCO officials indicated the pools could warm for four days without risking radiation release. Power was restored earlier this morning, and the pools should be back to normal temperature in a few days. During the repairs the charred remains of a rat were found in a critical area of wiring, leading some to believe that this rodent was the cause of this latest problem. At least it wasn't a mynock — then we'd really be in trouble."
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Towards a 50% Efficient Solar Cell

necro81 necro81 writes  |  about a year and a half ago

necro81 (917438) writes "IEEE Spectrum magazine has a feature article describing DARPA-funded work towards developing a solar cell that's 50% efficient, for a finished module that's 40% efficient — suitable for charging a soldier's gadgets in the field. Conventional silicon and thin-film PV tech can hit cell efficiencies of upwards of 20%, with finished modules hovering in the teens. Triple-junction cells can top 40%, but are expensive to produce and not practical in most applications. Current work by the Very High Efficiency Solar Cell program uses optics (dichroic films) to concentrate incoming sunlight by 20-200x, and split it into constituent spectra, which fall on many small solar cells of different chemistries, each tuned to maximize the conversion of different wavelengths."
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US Supreme Court rules against Warantless GPS Trac

necro81 necro81 writes  |  more than 2 years ago

necro81 (917438) writes "In a rare 9-0 decision, the U.S. Supreme Court has ruled (PDF) in United States v. Jones that law enforcement needed to obtain a search warrant before installing a GPS tracker on a suspect's car, then monitoring the car's movements. The Court split 5-4, however, on the scope of the ruling, and ruled largely on the fact that they installed the tracker on the defendant's private property (a car), sidestepping much larger questions about pervasive police tracking using GPS, cameras, and cellphones."
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HPV Vaccine Recommended for Boys

necro81 necro81 writes  |  more than 2 years ago

necro81 (917438) writes "An advisory committee to the U.S. Centers for Disease Control and Prevention will soon issue new recommendations that pre-adolescent boys be vaccinated against Human Papilloma Virus (HPV). The disease is sexually transmitted, endemic in the sexually active, can cause genital warts in both men and women, and is the primary cause of cervical cancer, which kills hundreds of thousands of women globally each year. The three-dose vaccination has been available for several years and already recommended for pre-adolescent girls. Vaccinating boys should further reduce transmission"
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Integrating Capacitors into Car Frames

necro81 necro81 writes  |  more than 2 years ago

necro81 (917438) writes "It has long been recognized that adding capacitors in parallel with batteries can improve the performance of hybrid and electric vehicles by accepting and supplying spikes of power, which reduces stress on the battery pack, extending range and improving cycle life. But where to put them, when batteries already compete for space? A new research prototype from Imperial College London has integrated them into the body panels and structural frame of the vehicle itself. In their prototype, carbon fiber serves as both the structure for the vehicle and electrode for the energy storage sandwiched within."
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Capturing Solar Power with Antennae

necro81 necro81 writes  |  more than 2 years ago

necro81 (917438) writes "Researchers at the University of Missouri and the Idaho National Laboratory have demonstrated a new method of capturing solar power. Rather than using semiconductors to capture photons of sunlight, they fabricated small coiled antennae (several um square) that resonate with the wave nature of light. The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth — even at night. They also demonstrated a way to imprint these coils on a substrate, like how CDs or vinyl records are produced, but could be scaled to roll-to-roll mass production. The usual caveat applies: it may be 5-10 years until this could hit the market."
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Cisco to Close Flip Camera Unit

necro81 necro81 writes  |  about 3 years ago

necro81 (917438) writes "When the Flip video camera arrived on the scene a few years ago, it made a splash. Compared to its camcorder brethren, it was smaller, lighter, easier, and cheaper. It was a much ballyhooed touchstone of the Good Enough Revolution. Competitors rushed in; the Flip evolved. Now the Flip is seeing its last days. Cisco, which bought Flip for more than $500 million just two years ago, will close Flip down as part of a money-saving restructuring. The ubiquity video-capable smartphones and pocket cameras has largely eliminated the Flip's niche market."
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Segway Company Owner Dies While Driving A Segway

necro81 necro81 writes  |  more than 3 years ago

necro81 (917438) writes "Jimi Heselden, the British multi-millionaire defense contractor and philanthropist, who bought the Segway company last December from inventor Dean Kamen, died yesterday after an accident while riding one of the machines. While using a ruggedized X2 version of the two-wheeled balancing scooter at his estate in North Yorkshire, he apparently drove over the edge of a precipice and into the River Wharfe. He was found later by a passerby and declared dead on the scene."
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Ted Stevens and Sean O'Keefe in plane crash

necro81 necro81 writes  |  more than 3 years ago

necro81 (917438) writes "The NY Times is reporting that former Senator Ted Stevens was aboard a small plane with eight others that crashed in remote southwest Alaska Monday night. Reuters is reporting that he died, along with at least four others. Meanwhile, the North American CEOof aerospace firm EADS and former NASA administrator Sean O'Keefe was was also reported in the crash. Rescue crews from the Alaska Air National Guard reached the site about ten hours after the initial crash."
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Poor Vision? There's an App for that.

necro81 necro81 writes  |  more than 3 years ago

necro81 (917438) writes "Researchers at MIT's Media Lab have developed a smartphone app that allows users to measure how poor their vision is (myopia, hyperopia, and astigmatism) and receive a corrective prescription. The user peers through a $2 optical adapter at the screen of a smartphone. The app displays lighted bars, and prompts the user to adjust the display until the bars line up. Repeating this with bars in different locations and orientations allows the vision distortion to be determined to within about 0.4 diopters (using a Nexus One). The iPhone 4, with its higher-resolution display, should be able to improve that to 0.28 diopters. This could have broad application in the developing world, where experienced opticians and diagnostic equipment are hard to come by."
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New Air Conditioner Process cuts energy use 50-90%

necro81 necro81 writes  |  more than 3 years ago

necro81 (917438) writes "The U.S. National Renewable Energy Laboratory has announced that it has developed a new method for air conditioning that reduces energy use by 50-90%. The DEVap system cools air using evaporative cooling, which is not new, but combines the process with a liquid dessicant for pulling the water vapor out of the cooled air stream. The liquid dessicant, a very strong aqueous solution of lithium chloride or sodium chloride, is separated from the air stream by a permeable hydrophobic membrane. Heat is later used to evaporate water vapor back out — heat that can come from a variety of sources such as solar or natural gas. The dessicants are, compared to typical refrigerants like HCFCs, relatively safe for the environment."
Link to Original Source
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Opportunity Rover breaks Viking 1 Record

necro81 necro81 writes  |  more than 2 years ago

necro81 (917438) writes "In the latest longevity milestone for the little-rovers-that-could, the Mars Exploration Rover Opportunity has become the longest operating Mars lander ever, passing the mark set by the Viking 1 lander back in the 1970s. Considering that Viking was an immobile, nuclear-powered science station, the 2246-sols (six Earth years) that the solar-powered roving Opportunity has racked up is even more impressive. Opportunity does not seem to be slowing down, either, it is still driving its way slowly towards Endeavor crater, which it hopes to reach in another two years. Its twin, Spirit , has fared less well of late, but may yet be heard from again."

Journals

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necro81 necro81 writes  |  more than 7 years ago http://hardware.slashdot.org/article.pl?sid=06/04/06/036222

Just bookmarking the 5 minutes of fame that the Cool Robot got here on slashdot.

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