Calculation

Ignoring the delta-v needed to get to/from orbits around planets at either end of the journey, and just calculating the delta-v needed to get from one circular orbit to another coplanar circular orbit around a primary body, e.g. the Sun, the vis viva equation says, where: is the speed of an orbiting body is the standard gravitational parameter of the primary body is the distance of the orbiting body from the primary ...

See also:

Hohmann transfer orbit, Hohmann transfer orbit - Calculation, Hohmann transfer orbit - Example; maximum delta-v, Hohmann transfer orbit - Low-thrust transfer, Hohmann transfer orbit - Interplanetary Superhighway

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The small sample variance properties of G are not known, and large sample approximations to the variance of G are poor. In order for G to be an unbiased estimate of the true population value, it should be multiplied by n/(n-1). The Gini coefficient is calculated as a ratio of the areas on the Lorenz curve diagram. If the area between the line of perfect equality and Lorenz curve is A, and the area underneath the Lorenz curve is B, then the Gini coefficient is A/(A+B). This ratio is expressed as a percentage or as the numerical equivalent of that perce ...

See also:

Gini coefficient, Gini coefficient - Calculation, Gini coefficient - Gini coefficients in the world, Gini coefficient - Development of Gini coefficients in the US over time, Gini coefficient - Advantages of the Gini coefficient as a measure of inequality, Gini coefficient - Disadvantages of the Gini coefficient as a measure of inequality

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Eccentricity of an orbit can be calculated from orbital state vectors as a magnitude of eccentricity vector: where: is eccentricity vector. For elliptic orbits it can also be calculated from distance at periapsis and apoapsis: where: is distance at periapsis, is distance at apoapsis. ...

See also:

Eccentricity orbit, Eccentricity orbit - Calculation, Eccentricity orbit - Examples

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In astrodynamics, the inclination can be computed as follows: where: is z-component of , is orbital momentum vector perpendicular to the orbital plane. ...

See also:

Inclination, Inclination - Calculation

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Various calculations have been published to arrive at the BSA without direct measurement, starting in 1916 with the Dubois & Dubois formula. A commonly used formula is the Mosteller formula, published in 1987: Metric (area in square metres from weight in kilograms and height in centimetres): half-English units (area in square metres from weight in pounds, height in inches): Another is the Haycock formula (in children): , Du Bois & Du Bois, Arch. inter ...

See also:

Body surface area, Body surface area - Uses, Body surface area - Calculation, Body surface area - Normal values, Body surface area - External link

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In astrodynamics the argument of periapsis can be calculated as follows: (if then ) where: is the vector pointing towards the ascending node (i.e. the z-component of is zero), is the eccentricity vector (the vector pointing towards the periapsis). In the case of equatorial orbits, though the argument is strictly undefined, it is often assumed that: where: is x-component of the eccentricity vector . In the case of circular orbits it is often assumed that the peri ...

See also:

Argument of periapsis, Argument of periapsis - Calculation

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In astrodynamics mean anomaly can be calculated as follows: where: is the mean anomaly at time , is the start time, is the time of interest, and is the mean motion. Alternatively: where: is orbit's eccentric anomaly, is orbit's eccentricity. ...

See also:

Mean anomaly, Mean anomaly - Calculation

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Utilizing the vis viva equation where, where: is the speed of an orbiting body is the standard gravitational parameter of the primary body is the distance of the orbiting body from the primary is the semi-major axis of the body's orbit The magnitude of the first delta-v at the initial circular orbit with radius r0 is: At rbSee also:

Bi-elliptic transfer, Bi-elliptic transfer - Calculation

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In astrodynamics eccentric anomaly E can be calculated as follows: where: is the orbiting body's position vector (segment sp), is the orbit's semi-major axis (segment cz), and is the orbit's eccentricity. The relation between E and M, the mean anomaly, is: For small values of e (e < 0.6627434) this equation can be solved iterativel ...

See also:

Eccentric anomaly, Eccentric anomaly - Calculation

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The eccentricity vector can be calculated from the orbital state vectors and at any time (the result is constant): where: is velocity vector of the orbital state vectors, is position vector of the orbital state vectors, is standard gravitational parameter. Alternatively it can also be computed from orbital angular momentum vector h: where: is orbital velocity vector, is orbital angular momentum vector, is orbital position vector,See also:

Eccentricity vector, Eccentricity vector - Calculation

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Quantitatively, the RCS is an effective surface area that intercepts the incident wave and that scatters the energy isotropically in space. For the RCS, σ is defined in three-dimensions as Where σ is the RCS, Pi is the incident power density measured at the target, and Ps is the scattered power density seen at a distance R away from the target. In electr ...

See also:

Radar cross section, Radar cross section - Measurement, Radar cross section - Calculation, Radar cross section - Reduction, Radar cross section - Purpose Shaping, Radar cross section - Active Cancellation, Radar cross section - RAM, Radar cross section - Optimization methods

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A double integral representation, as an alternative to the ones given above, may be derived from the series representation: using the formula for the sum of a geometric series. Integration by parts yields: An asymptotic expansion in terms of the Bernoulli numbers is . Trigamma function - Recurrence and reflection formulae. The trigamma function satisfies the recurrence relation: and the reflection formula: Trigamma function - Special values. The tr ...

See also:

Trigamma function, Trigamma function - Calculation, Trigamma function - Recurrence and reflection formulae, Trigamma function - Special values

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Atmospheric drag can be calculated as follows: where: cd is the body's coefficient of drag (that has to be determined experimentally), A is the body's cross-sectional area, ρ is the air density, and v is the body's velocity. ...

See also:

Atmospheric drag, Atmospheric drag - Calculation

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In a pure inclination change, only the inclination of the orbit is changed while all other orbital characteristics (radius, shape.. etc) remains the same as before. Delta-v () required for a pure inclination change () can be calculated as follows: where: is orbiting body's velocity at orbital position where maneuver takes place. For more complicated manuvers which may involve a combination of change in inclination and orbital radius, the amount of delta v is the vector difference between the velocity vectors of the ...

See also:

Orbital inclination change, Orbital inclination change - Calculation

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GDP deflator - Measurement in National Accounts. In most systems of National Accounts the GDP deflator measures the difference between the real (or chain volume measure) GDP and the nominal (or current price) GDP. The formula used to calculate the deflator is: Dividing the nominal GDP by the GDP deflator would then give the figure for real GDP, hence de ...

See also:

GDP deflator, GDP deflator - Calculation, GDP deflator - Measurement in National Accounts, GDP deflator - United States, GDP deflator - Hedonics, GDP deflator - United States

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The Impact Factor is generally calculated based on a three-year period. For example, the 2003 Impact factor for a journal would be calculated as follows: A = Number of times articles published in 2001-2 were cited in tracked journals during 2003 B = Number of articles published in 2001-2 2003 Impact Factor = A/B There are some nuances to this: ISI exclude certain article types (e.g. news items, correspondence, errata) from the denominator. Also, for new journals, ISI will sometimes calculate ...

See also:

Impact factor, Impact factor - Calculation, Impact factor - Debate, Impact factor - Inflation of Impact Factors, Impact factor - Skewness, Impact factor - Use in scientific employment

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APL was unique in the apparent speed with which it could perform complex matrix operations. For example, a very large matrix multiplication would appear to take only a few seconds on a machine which was much less powerful than those today. There were some technical and other economic reasons for this advantage: Commercial interpreters delivered highly-tuned linear algebra library routines. Very low interpretive overhead was incurred per-array—not per-element. APL response time compared favorab ...

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APL programming language, APL programming language - Overview, APL programming language - Examples, APL programming language - Calculation, APL programming language - Terminology, APL programming language - Character set, APL programming language - APL symbols and keyboard layout, APL programming language - Usage, APL programming language - Standardization, APL programming language - Quotes, APL programming language - Awards, APL programming language - Special characters

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Passer rating - NFL and CFL. The passer rating is determined by four statistics, each of which are computed as a number between zero and 2.375. The benchmarks for these statistics are based on historical averages. If any of the components are less than zero, they are reckoned as zero; if any are over 2.375, they are reckoned as 2.375. The completion percentage rating is calculated as The rating for average yards per attempt is calculated as The rating for touchdowns per attempt is calculated as The rating for inter ...

See also:

Passer rating, Passer rating - Calculation, Passer rating - NFL and CFL, Passer rating - College Football, Passer rating - Criticisms, Passer rating - Leaders

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The modulus of elasticity, λ, can be calculated by dividing the stress by the strain, i.e. where (in SI units) λ is the modulus of elasticity, measured in pascals F is the force, measured in newtons A is the cross-sectional area through which the force is applied, measured in square metres x is the extension, measured in metres l is the natural length, measured in metres < ...

See also:

Young's modulus, Young's modulus - Units, Young's modulus - Usage, Young's modulus - Linear vs non-linear, Young's modulus - Directional materials, Young's modulus - Calculation, Young's modulus - Tension, Young's modulus - Elastic potential energy, Young's modulus - Approximate values

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The Julian day number can be calculated using the following formulas: All divisions (except for JD) are integer divisions, meaning the remainder in the division is discarded. The months January to December are 1 to 12. Astronomical year numbering is used, thus 1 BC is 0, 2 BC is −1, and 4713 BC is −4712. For a date in the Gregorian calendar (at noon): For a date in the Julian calendar (at noon): For the full Julian Date, not counting leap seconds (divisions are real numbers): So, for example, 1 January 20 ...

See also:

Julian day, Julian day - Julian Date, Julian day - Alternatives, Julian day - History, Julian day - Calculation, Julian day - Other Usages, Julian day - Footnotes

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