enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. De novo peptide sequencing - Wikipedia

    en.wikipedia.org/wiki/De_novo_peptide_sequencing

    Look for the corresponding b-ions of the identified y-ions. The mass of b+y ions is the mass of the peptide +2 Da. After identifying the y-ion series and b-ion series, assign the amino acid sequence and check the mass. The other method is to identify b-ions first and then find the corresponding y-ions. [citation needed]

  3. Z-order curve - Wikipedia

    en.wikipedia.org/wiki/Z-order_curve

    The Z-ordering can be used to efficiently build a quadtree (2D) or octree (3D) for a set of points. [4] [5] The basic idea is to sort the input set according to Z-order.Once sorted, the points can either be stored in a binary search tree and used directly, which is called a linear quadtree, [6] or they can be used to build a pointer based quadtree.

  4. Quaternions and spatial rotation - Wikipedia

    en.wikipedia.org/wiki/Quaternions_and_spatial...

    Euclidean vectors such as (2, 3, 4) or (a x, a y, a z) can be rewritten as 2 i + 3 j + 4 k or a x i + a y j + a z k, where i, j, k are unit vectors representing the three Cartesian axes (traditionally x, y, z), and also obey the multiplication rules of the fundamental quaternion units by interpreting the Euclidean vector (a x, a y, a z) as the ...

  5. Cartesian product - Wikipedia

    en.wikipedia.org/wiki/Cartesian_product

    Cartesian product of the sets {x,y,z} and {1,2,3}In mathematics, specifically set theory, the Cartesian product of two sets A and B, denoted A × B, is the set of all ordered pairs (a, b) where a is in A and b is in B. [1]

  6. Sum of normally distributed random variables - Wikipedia

    en.wikipedia.org/wiki/Sum_of_normally...

    In the event that the variables X and Y are jointly normally distributed random variables, then X + Y is still normally distributed (see Multivariate normal distribution) and the mean is the sum of the means. However, the variances are not additive due to the correlation.

  7. Distribution of the product of two random variables - Wikipedia

    en.wikipedia.org/wiki/Distribution_of_the...

    The area of the selection within the unit square and below the line z = xy, represents the CDF of z. This divides into two parts. The first is for 0 < x < z where the increment of area in the vertical slot is just equal to dx. The second part lies below the xy line, has y-height z/x, and incremental area dx z/x.

  8. Electrical susceptance - Wikipedia

    en.wikipedia.org/wiki/Electrical_susceptance

    In electrical engineering, susceptance (B) is the imaginary part of admittance (Y = G + jB), where the real part is conductance (G). The reciprocal of admittance is impedance (Z = R + jX), where the imaginary part is reactance (X) and the real part is resistance (R). In SI units, susceptance is measured in siemens (S).

  9. Law of total covariance - Wikipedia

    en.wikipedia.org/wiki/Law_of_total_covariance

    Note: The conditional expected values E( X | Z) and E( Y | Z) are random variables whose values depend on the value of Z. Note that the conditional expected value of X given the event Z = z is a function of z. If we write E( X | Z = z) = g(z) then the random variable E( X | Z) is g(Z). Similar comments apply to the conditional covariance.