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    ztracené heslo?
    FALUCIUSVědecké vtipy
    MHO
    MHO --- ---
    KAERO: .... ten have not specified the conversion factor from metric units.

    To znamená co? Jakože se ta jejich stopa vztahuje k nějakému lokálnímu etalonu? Třeba mumifikovanému chodidlu otce zakladatele daného státu nebo tak něco?
    OMIKRONN
    OMIKRONN --- ---
    KAERO: "He resolved the problem by converting everything to international feet and massaging the vertical measurements" - jakože "He solved the problem by a foot massage"?
    HOWKING
    HOWKING --- ---
    ARCHIMEDES: Myslel jsi o 10^-12^60^144 :)
    ARCHIMEDES
    ARCHIMEDES --- ---
    VANEK: Easy, Amíci ať si zavedou "U.S. meter", který bude o 10^12^60^144 kratší než SI metr a redneci budou happy.
    KAERO
    KAERO --- ---
    VANEK: V tom clanku jsou dalsi perly:

    "Occasionally, surveyors must use one foot for horizontal measurements and the other for elevations. That happened to Dr. Dennis on an engineering project in Arizona. But while the geospatial software was capable of acknowledging both feet, it would not allow for different feet in different directions. He resolved the problem by converting everything to international feet and massaging the vertical measurements, which ought to have been in U.S. survey feet."

    "Even the National Geodetic Survey gets muddled. In a video about how not to mix up the two feet, it mixed them up. It wrongly said that 2,000 meters was 6,561.67 international feet and 6,561.68 U.S. survey feet, reversing the correct conversions. The error went unnoticed for years until Dr. Dennis watched the video recently as he plotted to kill the old foot. He was mortified."
    KAERO
    KAERO --- ---
    VANEK: tak treba pro mne je 2 ppm hodne :). Nicmene v tomhle videu je konkretni priklad chyby 22 ft (jakych?!) pri pouziti spatne stopy behem odvozovani od nejblizsiho NSRS referencniho bodu. Ony ty referencni body jsou nekde docela dost daleko od sebe, viz https://oceanservice.noaa.gov/facts/nsrs.html

    http://www.youtube.com/watch?v=kqd6Sk7brrk&t=105
    VANEK
    VANEK --- ---
    KAERO: Out of 50 states and six other jurisdictions, 40 have legislated that surveying measures should be based on the U.S. survey foot, six have legislated that they be made on the basis of the international foot, and ten have not specified the conversion factor from metric units. … the difference (2 ppm) is of no practical significance given the precision of normal surveying measurements over short distances (usually much less than a mile).

    Na daném odkaze ty výčty nejsou, ale při pátrání na webu jsem našel odkaz na tento pěkný čerstvý feature:
    https://www.nytimes.com/2020/08/18/science/foot-surveying-metrology-dennis.html
    In one case, in a certain city that Dr. Dennis declined to name, the construction of a downtown high-rise that sat in the approach path to an international airport was delayed while the building was redesigned to be one floor shorter.
    !!!
    “One thing is, let’s be honest, the actual name, the U.S. survey foot,” said Timothy W. Burch, the society’s president-elect, who is in favor of retiring the old foot. “For unfortunately a lot of Americans, especially in this day and age, anything that has to do with the U.S. and that naming quality being taken away, it’s like we’re under attack. So there is a portion of the country that’s like, No, this is ours, this is what we’re going to keep.”
    KAERO
    KAERO --- ---
    Jsem zjistil, ze kartografove ve Spojenych statech americkych pouzivaji dve ruzne stopy: U.S. Survey foot a International foot. Vtip je, ze vetsina statu ma jako standard jednu, a jen asi 6 pouziva druhou. Tresnicka na dortu je, ze NSRS (hlavni system souradnic Spojenych statu americkych) pouziva metry.
    Vymerit dalnici, ktera vede pres nekolik statu muze byt v severni americe ponekud matouci :)

    (rozdily stop jsou vyznamne, rozdil pri pouziti jedne nebo druhe stopy pri nejake vetsi vzdalenosti od bodu NSRS muze delat nekolik metru)
    SUMIE_DH
    SUMIE_DH --- ---
    BROUKOID
    BROUKOID --- ---
    HOWKING: ja zacnu protestovat az tam zacnou davat gender studies
    GORYTHC
    GORYTHC --- ---
    To ste slyšeli, že se teď do potravin bude dávat kromě chemie taky fyzika?
    HOWKING
    HOWKING --- ---

    :-D
    HOWKING
    HOWKING --- ---
    KAERO
    KAERO --- ---
    ALCATOR: Huste! Mimochodem typek ve videu jednoznacne podporil hypotezu c. 2 (CHOROBA): Grafik to myslel vazne a chape jak to doopravdy chodi
    :)
    ALCATOR
    ALCATOR --- ---
    HOWKING:
    87HIGHFLYER:

    Fšichni jste úplně vedle, samozřejmě :-) Autoři těchto grafik byli pouze vizionáři, kteří předběhli svou dobu.

    Tady je video plně funkční smyčky lichého počtu ozubených koleček, která se volně otáčejí:

    Are odd-numbered mobius-loop cogs possible?
    https://www.youtube.com/watch?v=nWQwrU1qUrc
    KAERO
    KAERO --- ---
    GAARQ: na popohaneni mrtveho kone neni nic spatneho, hlavne pokud je sfericky symetricky a ve vakuu!
    SUMAC
    SUMAC --- ---
    QUARATH: jo je to jako se souhvezdima. mince ma evokovat nekonecnost vesmiru :)
    QUARATH
    QUARATH --- ---
    A co kdyz sou ty ozubeny kola jen 2D zobrazeni a "ve skutecnosti" se nedotykaji...konec koncu zadna perspektiva tam neni ;)
    Kliknutím sem můžete změnit nastavení reklam