What is Finite: Definition and 1000 Discussions

The finite element method (FEM) is a widely used method for numerically solving differential equations arising in engineering and mathematical modeling. Typical problem areas of interest include the traditional fields of structural analysis, heat transfer, fluid flow, mass transport, and electromagnetic potential.
The FEM is a general numerical method for solving partial differential equations in two or three space variables (i.e., some boundary value problems). To solve a problem, the FEM subdivides a large system into smaller, simpler parts that are called finite elements. This is achieved by a particular space discretization in the space dimensions, which is implemented by the construction of a mesh of the object: the numerical domain for the solution, which has a finite number of points.
The finite element method formulation of a boundary value problem finally results in a system of algebraic equations. The method approximates the unknown function over the domain.
The simple equations that model these finite elements are then assembled into a larger system of equations that models the entire problem. The FEM then uses variational methods from the calculus of variations to approximate a solution by minimizing an associated error function.
Studying or analyzing a phenomenon with FEM is often referred to as finite element analysis (FEA).

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  1. B

    Linear Algebra: A Basis for a Finite Dim VS

    Why is it enough to prove that a set of vectors is a BASIS to a FINITE DIMENSIONAL Vector Space, it is enough to show that it is Linearly Independent. No Need to prove that it spans the whole vector space?
  2. P

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    Hi all, I am trying to solve a non linear differential equation iteratively using finite differences. At every iteration I basically have to solve (sorry, for some reason I cannot use the preview function when I write latex, so I'll write in plain text): Delta_x = (A-J)\b Where...
  3. R

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    I know the union can be, but how about the intersection? I am trying to prove that: Suppose (X,T) is a finite topological space, n is a positive integer and U_i\in T for 1<= i <= n. Use mathematical induction to prove \bigcap U_i \in T, where the intersection goes from i=1 to n.
  4. B

    Solved, i think (S is linearly indep. iff every finite ss of S is linearly indep.

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  5. M

    Is coutnable unions of finite sets an infinite set?

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  6. A

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  7. L

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  8. J

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  9. R

    Probability- finite n-th moment

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  10. F

    "Does Finite Group Contain Subgroup of Index 2 if Element has Order 2?

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  11. C

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  12. J

    Prove that an improper fraction with a finite binary expansion

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  13. A

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  14. A

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  15. 1

    MATLAB Finite difference method with matlab- square grid, cavity inside

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  16. L

    Finite fields and products of polynomials

    Homework Statement This question is in two parts and is about the field F with q = p^n for some prime p. 1) Prove that the product of all monic polynomials of degree m in F is equal to \prod (x^(q^n)-x^(q^i), where the product is taken from i=0 to i=m-1 2) Prove that the least common multiple...
  17. M

    Jellium Model: Finite Confinement & Coulomb Interactions

    Is the Jellium model only suitable for an electron gas of infinite volume? If I confined a gas to a finite volume using an infinite potential well, is there still a way to cancel out the infinities in the coulomb interactions between electrons?
  18. M

    Potential of Finite Quadrupole and Zonal Harmonics

    Homework Statement a) Find the potential of an axial quadrupole: point charges q, -2q, and q placed on the z-axis at distances L, 0, and -L from the origin. b) Find the potential only at distances r>>L. c) Show that this potential is proportional to one of the zonal harmonics.Homework...
  19. B

    Showing Multiple of 4 in Finite Group Equation

    Homework Statement In a finite group, show that the number of non-identity elements that satisfy the equation: x^5 = e = identity element of multiplication mod n = 1 is a multiple of 4. (Also need to show: if the stipulation that the group be finite is omitted, what can you say...
  20. V

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  21. S

    Population Growth with Finite Resources:

    Homework Statement Homework Equations <see above>The Attempt at a Solution I'm a bit unsure how to set this up to solve for a solution. Any advice? Its obviously a separable differential equation. But I'm unsure what it is I'm looking for. This looks different then some population...
  22. K

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    Homework Statement Show that the set of all finite subsets of N is a countable set. The Attempt at a Solution At first I thought this was really easy. I had A = {B1, B2, B3, ... }, where Bn is some finite subset of N. Since any B is finite and therefore countable, and since a union of...
  23. D

    Finite differences on scalar? Matrix?

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  24. V

    Drag coefficient for Finite circular cylinder of low aspect ratio

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  25. C

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  26. A

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  27. G

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  28. Shackleford

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  29. P

    Exploring the Finite Set of Integers Described in English

    It's simple for you mathematicians, but I'm a physician, I don't know much about set theory or logic and such, so it's difficult for me. Let M be the set of all integers that can be described in English in, say, ten lines of text. For example, "fourteen" or "seventy minus eight" or...
  30. radou

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    Homework Statement Let X be a topological space, and A a locally finite family of sets in X (i.e. such a family of sets that every point in X has a neighborhood which intersects a finite number of sets in A). One needs to show that Cl(U A) = U (Cl(A)) (i.e. the closure of the union of sets in...
  31. N

    Nonabelian finite group G

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  32. Z

    If the universe is flat and finite?

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  33. R

    Solving the diffusion equation finite difference technique

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  34. P

    Business Calculus or Finite Mathematics

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  35. M

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  36. D

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  37. T

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  38. D

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  39. radou

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  40. M

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  41. I

    Are Cyclic Groups with x^n = 1 the Only Finite Groups?

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  42. T

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  43. B

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  44. N

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  45. F

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  46. H

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  47. M

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  48. Z

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  49. K

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  50. J

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