When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Local standard of rest - Wikipedia

    en.wikipedia.org/wiki/Local_standard_of_rest

    In astronomy, the local standard of rest or LSR is a reference frame which follows the mean motion of material in the Milky Way in the neighborhood of the Sun (stars in radius 100 pc from the Sun), [1] on average sharing the same velocity around the Milky Way as the Sun. [2] The path of this material is not precisely circular. [3]

  3. Low thrust relative orbital transfer - Wikipedia

    en.wikipedia.org/wiki/Low_thrust_relative...

    Low-thrust relative transfer uses the orbital relative motion equations which are the non-linear set of equations that describes the motion of the chaser spacecraft relative to the target in terms of displacements along the respective axis of the accelerated frame of reference fixed on the target spacecraft.

  4. Specific orbital energy - Wikipedia

    en.wikipedia.org/wiki/Specific_orbital_energy

    Compared with the potential energy at the surface, which is −62.6 MJ/kg., the extra potential energy is 3.4 MJ/kg, and the total extra energy is 33.0 MJ/kg. The average speed is 7.7 km/s, the net delta-v to reach this orbit is 8.1 km/s (the actual delta-v is typically 1.5–2.0 km/s more for atmospheric drag and gravity drag).

  5. London Stock Exchange Group - Wikipedia

    en.wikipedia.org/wiki/London_Stock_Exchange_Group

    London Stock Exchange Group plc, also known as LSEG, is a global provider of financial markets data and infrastructure headquartered in London, England. It owns the London Stock Exchange (on which it is also listed), Refinitiv , LSEG Technology, [ 4 ] FTSE Russell , and majority stakes in LCH and Tradeweb .

  6. Symmetric mean absolute percentage error - Wikipedia

    en.wikipedia.org/wiki/Symmetric_mean_absolute...

    One supposed problem with SMAPE is that it is not symmetric since over- and under-forecasts are not treated equally. The following example illustrates this by applying the second SMAPE formula: Over-forecasting: A t = 100 and F t = 110 give SMAPE = 4.76%; Under-forecasting: A t = 100 and F t = 90 give SMAPE = 5.26%.

  7. Local-density approximation - Wikipedia

    en.wikipedia.org/wiki/Local-density_approximation

    Local-density approximations (LDA) are a class of approximations to the exchange–correlation (XC) energy functional in density functional theory (DFT) that depend solely upon the value of the electronic density at each point in space (and not, for example, derivatives of the density or the Kohn–Sham orbitals). Many approaches can yield ...

  8. Target angle - Wikipedia

    en.wikipedia.org/wiki/Target_angle

    It may be used to compute point-of-aim for a fire-control problem when vehicle range and speed can be estimated from other information. Target angle may be best explained from the example of a submarine preparing to launch a straight-run (non-homing) torpedo at a moving target ship. Since the torpedo travels relatively slowly, the torpedo ...

  9. Accessible surface area - Wikipedia

    en.wikipedia.org/wiki/Accessible_surface_area

    The number of points accessible is multiplied by the portion of surface area each point represents to calculate the ASA. The choice of the 'probe radius' does have an effect on the observed surface area, as using a smaller probe radius detects more surface details and therefore reports a larger surface.