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Paris Terror Spurs Plan For Military Zones Around Nuclear Plants

macpacheco Re:Domestic war (148 comments)

The safety systems are protected by a meter of concrete. Even an RPG / small mortar couldn't scratch that thick a skin.
It's not by chance that so far no real terrorists tried to attack / hijack a nuclear plant. It's not 1% as good a terrorist target as the anti nuclear paranoids state.

3 days ago
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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

macpacheco Actually it was a MAJOR partial SUCCESS ! (213 comments)

There were two goals far more important than actually recovering the first stage:
  1 - Having the stage navigate to the landing pad. It would have been a major failure if the rocket landed 2 miles away and were fished out of the water.
  2 - Not destroying the landing barge (its worth far more than the first stage, and it would take a few months to prepare another one).
Additionally, in less than 24 hrs SpaceX already knows what went wrong, have a fix for it, and intends to try again on the next launch (about 3 weeks from now, end of scheduled for January).
So, calling it a failure is like saying this glass is 10% empty !
SpaceX has already managed to have the rocket hover for a second or two meters from water, but back then there were no precision in where the rocket was aiming to splash. The difference is many changes were made to the rocket to steer it.
SpaceX might have a dozen shots at trying this in 2015 alone.

about two weeks ago
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Toyota Opens Patents On Hydrogen Fuel Cell Technology

macpacheco Re:Elon has it covered Was Re:Very clever (124 comments)

Tesla is 100% limited by Li Ion supply. Until the Giga factory is ready, Tesla can't divert Li Ion cells from high profit model S even to slightly lower profit model X.
The Gen III vehicle will be done, but it will take another 3-5 years.
I actually hope Tesla Model S + Model X demand will be so high the Gen III car will have to wait cause the initial giga factory output will be tied with Model S + Model X production. The most important goal Tesla must achieve isn't the Gen III car, but actually fully disrupting the Model S competition. Once BMW and Mercedes start having financial trouble cause people are buying a Tesla instead, we'll start having auto analysts realizing the electric car will take over.
Realize the BWM i3 is still a compliance car. BMW is still not serious about making a Tesla competitor. It seems like no company in the planet is even trying to compete with Tesla.
Its entirely possible Tesla will achieve 200 thousand Model S + Model X per year, at those scales Tesla might be able to drop the price a little bit due to higher economies of scale, further increasing demand. That won't make the MS/MX get to US$ 40k, but it might make the cheapest MS/MX get bellow US$ 60k with incentives, still sounds expensive, but over 10 years a driver might save the full cost of the car if driven a half a million miles + residual resale value of the car.

about three weeks ago
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Toyota Opens Patents On Hydrogen Fuel Cell Technology

macpacheco Fool cells are still fool cells ! (124 comments)

Every single fuel cell car is still an underpowered, unsexy car.
In the meantime Tesla is showing its cars can rival half a millon buck cars at less than 1/3 the price.
What Toyota will never conceed is that its fuel cell cars where never truly intended to replace gasoline cars. They are compliance cars, made strictly to comply with emissions regulations to offset the lowest mpg cars on Toyota's product line.
In the meantime Tesla is producing cars people actually want to buy, because its a high end car with all of its sex appeal !

about three weeks ago
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Why We're Not Going To See Sub-orbital Airliners

macpacheco The author doesn't fully understand the issue ! (300 comments)

The Concorde used a lot of fuel because it was based on a very outdated engine and it was a very heavy design. It was a design done before the 70s oil crisis, when fuel costs wasn't much of an issue. If you just replaced the mobile nose with cameras for landing + used F22 jet engines (must use an after burning jet engine, one that is capable of supersonic air intake), just that would reduce fuel consumption by a huge margin (as much as 2/3s).
People's time cost money. That doesn't apply to your average turism traveller, but I'd say over half of airline customers are willing to pay US$ 100/hr saved in travel time. That's US$ 2000 for a really long (London-Sydney, NYC-Hong Kong) trips.
BTW, the sabre powered airliner isn't quite sub orbital. It's a 80-90k feet airliner. Sub orbital is about 3x higher (above 100km or 300k ft altitude). Its still flying, just flying on thinner air.
Finally, the Sabre engine concept is also the only proposed airliner design that burns hydrogen instead of Jet fuel. Hydrogen made from natural gas still emits CO2 (on the ground, can be sequestered) but hydrogen could also be made by high temperature nuclear or hydrolysis directly from water. If the concept succeeds it might end up being mandatory for long haul flights due to the pollution argument alone.

about three weeks ago
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Airbus Attacked By French Lawmaker For Talking To SpaceX

macpacheco Re:So it is official. (168 comments)

Except Falcon Heavy reuses the Merlin 1D, Merlin 1D Vac, the basic first and second stage layout, and many other things from F9R. The Falcon Heavy is more similar in design to the F9R than F9R from the first version Falcon 9.
That being said, you are right, FH is still a power point rocket.

about a month and a half ago
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Airbus Attacked By French Lawmaker For Talking To SpaceX

macpacheco Re: So it is official. (168 comments)

Except the orbital rocket is useless for satellite launches. So it doesn't really count.
If you instead focus only on rockets that are launch commercial GEO payloads, then the only american product is SpaceX. Every now and then ULA does a commercial GEO launch, but its a tiny volume.
The really important factor is both ULA, Ariane and the Russians are old school space. SpaceX is silicon valley space, and so far, they model is making every competitor sweat. Like Elon Musk said in the first years of SpaceX, rockets have evolved little since the 70s. In a lot of ways SpaceX has evolved space affordability by leaps and bounds since the F9R rocket became fully operational and enabled SpaceX to launch (less than 4 ton) GEO satellites.
If the Falcon Heavy achieves the same success as F9R, it will undercut every SpaceX competitor in price even without reusability, and with first stage reusability its game over for every rocket currently operational in the world. SpaceX will be able to offer prices at least 50% cheaper than any competitor (in most cases 70-80% cheaper).

about a month and a half ago
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Utilities Face Billions In Losses From Distributed Renewables

macpacheco Re: Predictions (280 comments)

Ohhh so stupid... There is NO enterprise without PROFIT.
Communism doesn't work. Efficient people are greedy, regulated capitalism exploit greed to benefit the people. Without profit there's no capitalism.
At the same time... Electricity distribution will continue, it will just use a different electricity flow profile, it will be more focused on transporting electricity between consumers instead of from large generating assets to consumers.

about a month and a half ago
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Why Elon Musk's Batteries Frighten Electric Companies

macpacheco Re: Are they really that scared? (461 comments)

Clarification. In Brazil Solar+Wind is tiny today, but Solar+Wind should increase enough over the next 10 years that the total non CO2 emitting share of the grid (Brazil hydro + biomass + nuclear + solar + wind) should exceed 90%.

about a month and a half ago
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Why Elon Musk's Batteries Frighten Electric Companies

macpacheco Re: Are they really that scared? (461 comments)

And then there's Canada with hydro+nuclear+wind at 75%.

about a month and a half ago
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Why Elon Musk's Batteries Frighten Electric Companies

macpacheco Re: Are they really that scared? (461 comments)

You probably mean in the USA. In my Brazil hydro + biomass + nuclear + solar + wind is 85% of our MWh generated. Solar+Wind is a tiny part of that but over the next 10 years we should increase that to 90% minimum. We're what German is hoping to be 20 years from now. Except we have NO plans to get rid of nuclear, in fact we're building our 3rd reactor with plans for at least another 4 new nuclear projects over the next 15 years.
France is 90% nuclear + hydro + solar + wind. Except the dumbasses are looking to get rid of nuclear. Bad idea.

about a month and a half ago
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Is Chernobyl Still Dangerous? Was 60 Minutes Pushing Propaganda?

macpacheco Re:according to the pro-nuclear lobby; (409 comments)

Wrong. Chernobyl was dangerous. Very dangerous in the first few weeks due to the most radioactive fission products still undergoing decay. Until they finished the Sarcophagus is was very dangerous still. A year after the Sarcophagus is was just dangerous.
And we have to differentiate distance to the reactor. Radioactivity disperse under a inverse square law, so x of radioactivity 1 mile away = x/100 radioactivity 10 miles away.
But ten years after the Sarcophagus was completed all of the very dangerous radiation has decayed. The real remaining risk is drinking / eating alpha emitters. The gamma/beta rays menace is pretty much gone at this point.
30 years later the longer lasting fission products have decayed by 50%
60 years later the longer lasting fission products have decayed by 75%
The other part of the analysis is how much of the radioactive materials have been washed away underground and into rivers.
The plutonium radioactive menace isn't significant as its just a few tens of KGs spread over many square Kms.
Plutonium and uranium is far more dangerous due to its chemical toxicity than due to its radioactivity.
But discussing those inconvenient facts aren't conductive to the main goal which is to severely bash nuclear power as inherently dangerous, while the world keeps burning the really dangerous coal, which kills even without an accident.
My conclusion is quite simple, the american mainstream media isn't in love with renewables, they are being paid of by the coal industry, since they would be attacking coal every day if they truly cared for a clean environment.
Chemical toxic materials have no half life, they stay dangerous forever. Solar panels incorporate lots of chemicals that will be toxic forever.
The other 400 nuclear reactors in operation in the world show that nuclear power can be safe and is safe.

about 2 months ago
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Is Chernobyl Still Dangerous? Was 60 Minutes Pushing Propaganda?

macpacheco What matters ! (409 comments)

The Chernobyl nuclear accident couldn't have happened with a western reactor built to NRC specs be TMI.
Secondary containment would have held or at the very least contained the bulk of the radiation.
The reactor control rod design was utterly defective, the trouble really started when the reactor's control rods were inserted quickly, instead causing the reactor to runaway.
In the meantime, from Chernobyl until today Coal killed many millions of people.
I would love to read a serious (scientific) report from those that claim Chernobyl killed one million people. It's been 25 years, so please document at least 20 thousand deaths, name, date of birth and date of death, along with a diagnosis / coroners report showing death by cancer likely to be caused by nuclear radiation.
Instead the professional people that fear a real debate bomb slashdot with ad hominem attacks on why slashdot sucks.
My simple conclusion is: A nuclear accident even halfway between Chernobyl and Fukushima in severity is impossible.
Many here are just to young to understand what the USSR was all about: People are expendable.
The Chernobyl accident was exposed to breach every layer of defense in depth required to license a nuclear reactor even before TMI.
Think about it.

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Re:FBR fast breeder reactors (138 comments)

If you dig really deep, you will find out that all of nuclear technology is too expensive in the NATO land. Its population was brainwashed with lies about Three Mile Island, Chernobyl and Fukushima and believe nuclear is a thing of the devil. They irrationally demand nuclear is shutdown, but the pro nuclear lobby pushes back, in the squeeze the NRC (and its sister organizations) create an insane level of absurd extreme anti nuclear regulation that led nuclear power to be too expensive.
All you need to do is compare the cost of a new nuclear reactor in the USA/France/UK with the costs in Russia,China,India and South Korea. The pro nuclear countries can build the SAME reactor for 80% cheaper. So while FBR reactors are currently more expensive than LWR/BWR/HWRs, that is due to its learning curve. If we were building a few dozen FBRs in the world we would quickly learn how to build the faster, we would get better economies of scale (as we move to build a hundred of the simultaneously), and soon they would be cheaper than water cooled nukes (because they are actually much simpler to build, much less complexity).
I would be happy to enumerate all the reasons why an FBR in essence must be cheaper than current water cooled nukes and why an MSR will be ever cheaper than an FBR if you would like to discuss.

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Re:Nevada, not Utah (138 comments)

The anti Yucca plan was based on ignoring science.
But we should instead reprocess spent nuclear fuel.
Leave spent nuclear fuel to cool for a few decades (at the nuclear station), the reprocess the fuel. Out of reprocessing we would get:
    Uranium = put it through enrichment again (make more depleted uranium which is harmless and some low enriched uranium for new fuel)
    Plutonium = mix with depleted uranium and make mox nuclear fuel
    other transuranics = that would go for very long storage until a fast reactor is available to fission it
    fission products = could be further separated between medium radioactivity materials (20%) and fully decayed materials (80%). the medium radioactivity materials have 30 year half lifes, need storage for about 300 years, then its less radioactive than original uranium fuel
      fission products contain lots of extremely valuable minerals like rare earths used to make wind turbines, cell phones, tablets, solar panels and other high tech stuff
In the end the fission products might use a Yucca mountain if we opt not to separate the results of reprocessing. But its important to understand that for each ton of fission product made we avoided generating millions of tons of CO2 and generated enough power to serve the needs of about a half a million people for a whole year ! And we were desperate to do carbon sequestration, yet here we have perfectly sequestered, dense nuclear products and we don't realize this stuff is perfectly manageable (even without reprocessing).

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Re:Mildly off-topic, but... (138 comments)

All true, but Polonium isn't produced by nuclear fission. It is a decay product of fissile/fertile material. It is produced from potential nuclear fuel we don't use.
Nuclear reactors deal with alpha emitters with half lifes in the multi thousand to million year half life. In general those materials are far more deadly due to their chemical toxicity rather than its radioactivity. The lowest half life alpha involved in nuclear reactors is in the 50 thousand + year half life (U-233 and some plutonium isotopes). Plutonium is far more dangerous from its toxicity than its radioactivity if ingested.

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Re:Mildly off-topic, but... (138 comments)

For a nuclear reactor, there are essentially three types of nuclear materials:
  1 - Fissile material (hit it with a neutron and it has a high probability - from 60% to 99.9% of fission)
  2 - Fertile material (hit it with a neutron and it turns into Fissile material)
  3 - Fission products - new atoms resulting from fission

Fission products typically are highly radioactive materials, but they have already undergone fission. Many of them are fission poisons (they are neutron magnets to make it simple). So the longer they stay in the reactor, the more they tend to poison the nuclear chain reaction (its all about the neutrons). Although they release energy, their neutron absorption is very undesirable inspite of their energy release. This is specially true for Gaseous fission products (Xenon and Krypton).

So while fission products could make useful nuclear thermal batteries (similar to the Plutonium 238 batteries used in space missions), they aren't terribly useful to keep around inside a reactor for long.

Nuclear fission releases a boatload of energy. We don't need to depend on decay of fission fragments to supplement that energy.
In general fertile materials have very high half life (ultra low radioactivity), with half lifes over millions of years.
Fissile materials range widely in half lifes, from tens of thousands of years to many millions or years.
Fission fragments in general have half lifes of less than 30 years, some with half lifes in seconds to a few weeks. So fission fragments are a much bigger radioactive menace, but if they were separated from the fertile/fissile materials we would get a very limited volume of material for a very large level of energy produced. One ton of fission products = around 3 Gigawatts power of thermal heat for a whole year or 1GW year of electricity, or 8760000000 kWh of electricity (8.76 billions of kWh). Put it another way, all nuclear reactors in the world produce around 400GW of electrical power, they also produce around 400 tons of fission products per year, that's enough electrical juice to essentially power all of North America. To do that with coal it would take about one billion tons of coal (and would generate about 2.86 billion tons of CO2).

The real problem is nuclear technology got stuck in the 50s. We never left water cooled, solid fuel reactors, which are very lousy in their ability to fission U-238 (99.3% of mined uranium). While reactors greatly increased in power levels and increased significantly in safety, we waste a lot of mined uranium.

250 tons of mined Uranium is needed to produce 35 tons of low enriched uranium suitable for nuclear fuel (215 tons of depleted uranium created)
of 35 tons of uranium made into nuclear fuel, about 1 ton is fissioned
of those 34 tons of unfissioned uranium one ton is transmuted into fertile material (mostly plutonium) that has intermediate radioactivity levels (takes millenia to decay and produces just enough radiation that it would be deadly if ingested even in tiny quantities, but not enough radiation to even cause cancer if you lived your entire life a 20 meters from a Kg of Plutonium). But we have solutions to fission all of that material. Fast Sodium reactors were in very late stages of engineering prior to hand off of technology to the private sector (a few years) when Bill Clinton, Al Gore and John Kerry killed that research in the early 90s. It was a very stupid decision, 99.9% to please the radical green wing of the democratic party. Russia has been operating one large fast reactor for 30 years (BN-600) has just started up the next generation BN-800, and should have the final full scale reactor BN-1200 operational in less than 10 years. Any of those could just take in those transuranics (the troublesome fissile material we want to fission) without problems.

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Re:Molten Salt Reactor FTW (138 comments)

True, Fast reactors, reduced moderation reactors could also get the job done (fissioning most of the Uranium on spent nuclear fuel or newly mined uranium or Thorium).

about 2 months ago
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Shale: Good For Gas, Oil...and Nuclear Waste Disposal?

macpacheco Nuclear storage must be temporary (138 comments)

Spent Nuclear Fuel is still FUEL !
At least 98% of SNF is fissile / fertile nuclear material.
Out of 35 tons of Enriched Uranium used to make fuel, just 1 ton is fissioned, 34 tons remains as Uranium, Plutonium, Neptunium, Americium and Curium. All of that stuff can be fissioned using a fast reactor. Using more complex reprocessing Uranium and Plutonium can be extracted and recycled into fuel any reactor could use.
The USA isn't doing nuclear fuel reprocessing due to economical reasons, the technology is available, the French, Japanese, Russians and others reprocess nuclear fuel all the time.
Using higher efficiency nuclear reactors (Fast reactors, Molten Salt Reactors or Reduced Moderation water cooled reactors a virtuous cycle where with reprocessing at least 99% of mined uranium could be fissioned). Why is that important ? If we used high efficiency reactors a typical person would use less than 1Kg of Uranium for all of their energy needs for their entire lifetime, and that 1Kg of Uranium would become 1Kg of fission products. 80% of fission products are stable in a few decades, the remaining 20% are stable in 300 years.
So any plan to inject SNF into shale rock is stupid. We should instead be investing on fast reactors. If all the money put into Yucca mountain went into MSR research we would already have two designs hitting the market. Even the most basic MSR Uranium burner uses 1/6th the Uranium a regular reactor needs per GWh of electricity produced.

about 2 months ago
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Wikipedia's "Complicated" Relationship With Net Neutrality

macpacheco Re:Contradictions (134 comments)

Really low bandwidth is 99% text with fairly small pics. Like Wikipedia.
Music is medium bandwidth, assuming that wikipedia (or slashdot) is actually read and pics are looked at intently.

about 2 months ago

Submissions

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GPS L2C/L5 pre operational signal available

macpacheco macpacheco writes  |  about 9 months ago

macpacheco (1764378) writes "For ages, high accuracy GPS meant using a mix of civilian and military signals.
In order to obtain high accuracy GPS positioning (better than 2 meters) receiver must know local ionosphere corrections. This requires two GPS signals at a minimum, the difference between both is used to calculate ionospheric corrections which is then applied to either one.
However since GPS doesn't offer two usable civilian signals, a technique known as semi-codeless was devised, that calculates ionosphere corrections by using the two military encrypted signals L1P(Y)+L2P(Y), then applies the iono corrections to the civilian L1 C/A signal, however the military was never to fond of that usage, since it limits what changes they can do with the military signals. Specially changes in power levels.
Since September 26, 2005 GPS satellites capable of broadcasting the L2C (2nd civilian signal) and since May 2010 GPS satellites capable of broadcasting the L5 (3rd civilian signal, usable for aviation) have been launched, however those signals are still not fully usable.
Today those signals were enabled in a pre operational format meaning:
  1 — All messages required for full L2C and L5 utilization are broadcast
  2 — L5 signals are broadcast with an alert flag (not usable), L2C is broadcast without an alert flag
  3 — L2C/L5 almanac and ephemeris will be updated about twice a week, while regular L1 C/A updates happen typically twice a day, so L2C and L5 signals will be less accurate in this phase

However this means there is no technical excuse for GPS equipment manufacturers to finalize their L2C and L5 offerings, since they now have a complete signal to test against, and right after GPS satellites have received an upload they should have similar accuracy as L1 C/A.
This should continue for the next few years, until the new GPS control segment, OCX comes online, OCX block 1 is needed for full L2C capabilities and OCX block 2 is needed for full L5 capabilities.
Notice that it will take at least another 12 GPS launches for L2C to reach a state known as FOC (full operational capability), meaning that are enough satellites with L2C capability for L2C to be usable for standalone positioning and it will take another 19 GPS launches for L5 to reach FOC as well."

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Forbes tries to smear Tesla and gets burned !

macpacheco macpacheco writes  |  about a year and a half ago

macpacheco (1764378) writes "Very interesting to read a clearly Big Oil sponsored article, and then read all comments, not a single comment supporting the writer's stupid, short sighted views.

Forbes needs to first write articles scathing the trillions of dollars the Oil + Coal industry got in subsidies over the last 50yrs before they be allowed to try to criticize the solutions to our pollution problems !"

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USA Election. It's the productivity dummy !

macpacheco macpacheco writes  |  more than 2 years ago

macpacheco (1764378) writes "Another critical fact neither the GOP nor the Dems address which is critical to economical recovery:
In 1970, a business needed as many as 10x more employees to accomplish the same administrative tasks (invoicing, payroll, accounting, IT, production planning, inventory), as today.
After the PC revolution, businesses needed less people to do the same, they got fired, but the services sector re-used them for other jobs, many started businesses of their own. However their a limit to how many people large businesses can fire until the economy can't re cycle them. The current economy is getting too productive. B2B and B2C processes are further reducing the number of employees needed to get the job done.
Eventually there will be next to none clerical employees, forklift jobs get automated, robots take over production. How can the economy re accomodate that labor force ? The services sector need customers ! Eventually unemployment will rise. Don't we need to have some limits to automation to ensure that manufacturing actually hires ?
If the whole economy hires 10% of what it did in the pre PC age, how is full employment possible ?
That's a difficult question no sides are willing to answer."
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Mitt Romney, conservative/moderate or just plain liar ?

macpacheco macpacheco writes  |  more than 2 years ago

macpacheco (1764378) writes "After listening to the 47% tape, following the Republican primaries and the first month of all out electoral campaign, I'm puzzled.

Is Romney just a flip flopper, or is he a pathological liar ?
People that tell you what they want you to hear, just because they can get away with it, no matter how untrue, are the worse type of politician and human beings on the planet.

I'm not from the US (I'm from Brazil), if I was a US citizen, I'd be an independent, I would vote for Obama not because I like him, but instead because I think the current generation of Republicans are just 10 times worse !

I do have an agenda, I'm a pragmatic environmentalist, and I'm against all kinds of corporative inefficiency, specially the government type of corporative inefficiency. The Dems have their faults, but the GOP fails to show any way that they actually mean to do the positive side of their agenda."
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Smaller, cheaper lighter atomic clocks are here

macpacheco macpacheco writes  |  about 4 years ago

macpacheco (1764378) writes "Atomic clocks for a long time have been a research lab item, used in production environments only in high budget, ultra performance demanding environments. Their high power consumption, 4U size and weight also didn't help.
Chip scale atomic clocks (CSAC) have been a promise for a long time. They're finally here. Typical atomic clocks cost tens of thousands of dollars each, this first generation CSAC costs US$ 1400 in small quantities. 1 cu inch volume (16 cc), 115mW power consumption (down about 1000 fold), and just 35 grams weight, will make them more interesting than current GPS based frequency standard.
They're called frequency standard, because 99% of the time someone needs an atomic clock, it's not to actually track time (day, hour, minutes, seconds, milliseconds), its used instead a replacement for quartz crystal oscillators, mainly transmitting and receiving radio signals, synchronizing telecommunications equipment. This atomic clock claims to be about 10000 times more accurate than typical quartz based oscillators.
This is very exciting, as it will enable better 4g/WiMax/... base stations, better ultra high speed networking equipment, and will help tremendously in GPS augmentation solutions like WAAS, EGNOS, DGPS. Having an atomic clock on a GPS receiver works like an extra GPS satellite."

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