Search results
Results From The WOW.Com Content Network
The set of all velocities through a given point of space is known as the tangent space, and so df gives a linear function on the tangent space: a differential form. With this interpretation, the differential of f is known as the exterior derivative , and has broad application in differential geometry because the notion of velocities and the ...
One thinks of δF/δρ as the gradient of F at the point ρ, so the value δF/δρ(x) measures how much the functional F will change if the function ρ is changed at the point x. Hence the formula ∫ δ F δ ρ ( x ) ϕ ( x ) d x {\displaystyle \int {\frac {\delta F}{\delta \rho }}(x)\phi (x)\;dx} is regarded as the directional derivative at ...
When f is a function of several variables, it is common to use "∂", a stylized cursive lower-case d, rather than "D". As above, the subscripts denote the derivatives that are being taken. For example, the second partial derivatives of a function f(x, y) are: [6]
FDFD simulation of light diffraction from a plasmonic slit. The finite-difference frequency-domain (FDFD) method is a numerical solution method for problems usually in electromagnetism and sometimes in acoustics, based on finite-difference approximations of the derivative operators in the differential equation being solved.
High-frequency direction finding, usually known by its abbreviation HF/DF or nickname huff-duff, is a type of radio direction finder (RDF) introduced in World War II. High frequency (HF) refers to a radio band that can effectively communicate over long distances; for example, between U-boats and their land-based headquarters.
A Palestinian toddler who doctors say only has days to live without urgent medical treatment was evacuated from Gaza by the Jordanian military on Monday, in a special mission after Israel had ...
Remove the ribs from the oven and reduce the temperature to 275°F. Using tongs, gently transfer the ribs to a large plate. Discard the used aluminum foil and re-line the baking sheets with fresh ...
For any differential field F with derivation D, there exists a subfield called the field of constants of F, defined as: Con(F) = {f ∈ F | Df = 0}. The field of constants contains the prime field of F. Given two differential fields F and G, G is called a simple differential extension of F if [1] and satisfies ∃s∈F; Dt = Ds/s,