Slashdot Mirror


User: js7a

js7a's activity in the archive.

Stories
0
Comments
987
First seen
Last seen
Profile
(view on slashdot.org)

Comments · 987

  1. frequency != bandwidth on How Reliable is 900Mhz Wireless Internet? · · Score: 2, Informative
    @ 900 MHz, the bandwidth is 900 MHz

    On the contrary, as has been pointed out, frequency is not bandwidth.

    it is technically possible to hit this raw rate of data transfer.

    Actually, it is possible to approach the Shannon channel capacity the way you calculated it, but impossible in practice to achieve it. Technical possibility is not the same as theoretical maximum throughput.

  2. Re:Waste Heat on What if Energy was (Nearly) Free? · · Score: 1
    How does a link to CO2 concentration have anything to do with heat trapped in the troposphere? Based on the fact that it gets cold in my room every night, I would venture to guess that the planet is capable of removing heat from the atmosphere at a much faster rate than you suggest....

    The heat that becomes trapped in the atmosphere is also represented in stronger storms and additional transpiration and evaporation, resulting in additional cloud formation. Those are energy pathways that you are apparently not considering.

    The scientific consensus about some of the more dangerous of those pathways has been reinforced in recent years, and in the past month. If you are unable to find the answers you seek with Google/News, please let me know.

  3. Re:Waste Heat on What if Energy was (Nearly) Free? · · Score: 1
    Let me guess: You've never seen any windmills other than those in Altamont Pass.

    The 2.5 megawatt turbines from Denmark do not kill birds, and they are essentially quiet.

  4. Re:Waste Heat on What if Energy was (Nearly) Free? · · Score: 1
    Anyone care to take a guess at how much heat we would need to pump out in order to significantly impact global temperatures directly?

    If everyone on the planet converted from fossil fuel to wind powered electricity in 30 years, it would take another 300 years to undo the excess heat trapped in the troposphere over the past 300 years

  5. in the future on Science Faction · · Score: 4, Funny

    In the future we will have newspapers that automatically repeat themselves.

  6. synthetic aperature interferometry needs 2 MOSTs on The 'Humble Space Telescope' Successfully Launched · · Score: 1
    Thank you for the pointer to the pertinent poster. I think I know the answer to the question. 2 MOSTs should be able to do very precise synthetic aperature terrestrial planet finding.

    GO CANADA! NASA can't tell Earth from Jupiter.

  7. Re:synthetic apperature interferometry? on The 'Humble Space Telescope' Successfully Launched · · Score: 1
    Images are not necessary at this stage.

    Can MOST detect N2, O2, H2O, O3 with reliable temperature information? Or is it limited to gas giants?

  8. Re:Tungsten T not relevant on External Antennas for Tungsten C Handhelds? · · Score: 1

    Hey, Todd, what kind of cpu do the high-end PalmOS systems have these days?

  9. it's scientists' own fault on 10th Anniversary Of Supreme Court's Daubert Ruling · · Score: 1
    If only "peer-reviewed, meticulous studies" were written with much less jargon and fewer unexpanded abbreviations and acronyms, as journal articles 80 years ago ordinarily were, then the courts wouldn't balk so much at exposing science to juries.

    Don't blame advances in technology, it doesn't take much work to proofread for avoidable jargon and overly obscure terms.

  10. Mr. Project on MandrakeSoft's Status Update · · Score: 2, Informative
    Mr. Project can do Gantt charts.

    It needs GNOME under Linux (not BSD for some reason) and can't import MS Project files (yet), but you can print charts.

  11. synthetic apperature interferometry? on The 'Humble Space Telescope' Successfully Launched · · Score: 3, Informative
    From the MOST project summary ("Detection and characterisation of ... reflected light from giant exoplanets closely orbiting Sun-like stars, to reveal their sizes and atmospheric compositions...."), it would seem that they are trying to break some planet finding ground, but it is unclear to me whether the control and position systems are accurate enough for synthetic apperature interferometry.

    Are they? If so, are they planning cooperation with land-based or other space telescopes?

    P.S. Has anyone noticed that NASA/JPL switched the labels of Earth and Jupiter in this picture on the "What is TPF?" page?

  12. Re:Hydrogen from biowaste is stupid. on Cheaper, Cleaner Hydrogen Without Platinum · · Score: 1
    We were all biowaste at one time.

    I like pond scum.

  13. Bush is also the coal industry on Cheaper, Cleaner Hydrogen Without Platinum · · Score: 1, Flamebait
    Some of Bush's closest friends are big players in the synthetic fuels industry, which makes liquid fossil fuels from coal and shale. The correct solution, however, is wind power, which directly mitigates such damages.

    You have to wonder about a politician who doesn't tell voters about his drunk driving conviction, because, he said, he didn't want to set a bad example for his children and then doesn't tell the Secret Service to keep them out of bars underage. Maybe he thought it went without saying. I guess you've got to be very precise when you've got pardoning powers.

    Neither precision nor accuracy are Bush's strong suits.

  14. weather looks great on Experimental Fuel-Cell Airplane's 2nd NASA Test · · Score: 1

    Thursday's skies show no clouds over Hawaii, and perhaps 15% scattered clouds out hundreds of miles. Go for it!

  15. Helios speed on Experimental Fuel-Cell Airplane's 2nd NASA Test · · Score: 1
    Helios which reaches astounding speeds of 30 MPH

    ...at sea level. At 70,000 ft., the Helios can travel at 150 MPH.

  16. Re:Radio Ground Coverage on Experimental Fuel-Cell Airplane's 2nd NASA Test · · Score: 2, Interesting

    There's more to it than that. Once you're above the troposphere, you get to use the ionosphere as a reflector with much less penalty. That's how over-the-horizon radars work.

  17. Li-ion cars on Building Longer-Lived Fuel-Cell Stacks · · Score: 1
    A prototype Li-Ion battery-powered car costs 1/4 as much, travels 3 times as far (350 miles) and weighs less than todayâ(TM)s typical fuel cell powered car and can be effectively produced TODAY.

    I'm interested. Do you have URL(s) supporting that claim?

  18. m.p.u. on ESA's Beagle 2 Hits Signal Snag · · Score: 1

    I wish I had mod points for this. ROFL!

  19. Re:expensive != easy on A Mighty Wind · · Score: 1
    The minimum size of a nuclear plant is determined by the distance neutrons must travel before being a) thermalized and b) captured. Both of these are many, many orders of magnitude larger than "nanoscopic".

    Fine, for enrichment purposes we are talking distances of 30 to 60 cm. Surely the bad guys will never build anything that immense.

    If I'm a troll, you're a proliferator.

  20. Re:expensive != easy on A Mighty Wind · · Score: 1
    How does a gigantic power plant "fall" into *anyone's* hands?

    Any rationalization that depends upon the alleged inability to minaturize inherently nanoscopic processes is intellectually bankrupt from the start.

  21. Re:expensive != easy on A Mighty Wind · · Score: 1
    A fission plant capable of producing useful quantities of weapons-grade material is big.

    That would be nice.

    anything less than bury it at the bottom of a mine shaft

    A few dozen yards into a cave the side of a cliff is about the same as the bottom of a mine shaft as far as synthetic aperature satellites are concerned.

    A "small group of people" can't build a weapon-supplying reactor.

    Let's hope you're right. The more the civilized world relies on nuclear power, the easier it becomes for it to fall into the wrong hands.

    Remember in 1992 when governments told us that liquid-phase centrifuges were worthless for refining isotopes? I recall that story lasted three years before some official denied it.

  22. Re:expensive != easy on A Mighty Wind · · Score: 1
    Nuclear plants are big

    Fission plants need not be large. What evidence do you have that a fission plant could not operate in a 10x8x12ft toolshed? These things power many sizes of submarines, remember.

    expensive

    I'm glad to have convinced you.

    and impossible to hide (gamma signature can penetrate just about anything if you take the time to look for it)

    On the contrary, I have an EM spectrum chart that the Exploratorium sold me for a few dollars that has everything anyone needs to know about shielding up to 938 Mev. You can use water or lead, but mountain soil is usually the easiest.

    How exactly is my supporting nuclear power in Canada proliferating nuclear weapons, again?

    It is because proliferation risks are continiously devolving from nations to small groups of people. To rely upon something that you don't want everyone to have is contradictory policy.

    How does proliferation relate to the half-dozen "nuclear power is ludicrously expensive" posts you littered this thread with?

    Subsidies can not eliminate externalities.

  23. Re:expensive != easy on A Mighty Wind · · Score: 1
    proliferation issues are utterly irrelevant to a discussion of how much nuclear power costs

    On the contrary, they are valid externalities, and we ignore them at our peril and that of our decendants.

    Please don't ask me to support your cheap nuclear power when doing so means that the empowered radicals obtain cheaper nuclear weapons.

  24. AWEA and proliferation actuarial costs on A Mighty Wind · · Score: 1
    First of all, the AWEA is woefully underinformed when compared to their leader, their Dutch counterpart WindPower.org, which please see. The AWEA refuses to even return my telephone calls.

    What are the actuarial costs of promoting nuclear energy in the U.S. at a time when the U.S. is asking the international community to more closely monitor Iran's research and development in nuclear energy?

  25. Re:expensive != easy on A Mighty Wind · · Score: 1
    You keep throwing this number around, but have yet to provide any source or justification for it.

    In fact the last number I quoted before this thread was $0.45/kwh, which came from Googled material via "Price-Anderson Act" (which was in the news less than a year ago having been up for renewal) relating to an actuarial bid from Lloyds of London, quoted was during the Chernobyl era. Granted, however, that it has been a long time since any commercial insurance company was asked to bid on a nuclear power coverage policy.

    The fact is, until the market is asked to bear these risks, instead of the taxpayers, nobody will know how much it costs to insure nuclear electricity. $0.20/kwh is a guess, not a quote.

    I'm tired of people ignoring the background proliferation issues. If we in the U.S. butild more nuclear, what does that do to our ability to ask the international community to help prevent Iran from building more "research" reactors?