In mathematical optimization, the Karush–Kuhn–Tucker (KKT) conditions, also known as the Kuhn–Tucker conditions, are first derivative tests (sometimes called first-order necessary conditions) for a solution in nonlinear programming to be optimal, provided that some regularity conditions are satisfied.
Allowing inequality constraints, the KKT approach to nonlinear programming generalizes the method of Lagrange multipliers, which allows only equality constraints. Similar to the Lagrange approach, the constrained maximization (minimization) problem is rewritten as a Lagrange function whose optimal point is a saddle point, i.e. a global maximum (minimum) over the domain of the choice variables and a global minimum (maximum) over the multipliers, which is why the Karush–Kuhn–Tucker theorem is sometimes referred to as the saddle-point theorem.The KKT conditions were originally named after Harold W. Kuhn and Albert W. Tucker, who first published the conditions in 1951. Later scholars discovered that the necessary conditions for this problem had been stated by William Karush in his master's thesis in 1939.
Homework Statement
Solve the diffusion equation:
u_{xx}-\alpha^2 u_{t}=0
With the boundary and initial conditions:
u(0,t)=u_{0}
u(L,t)=u_{L}
u(x,0=\phi(x)
The Attempt at a Solution
I want to solve using separation of variables...
I start by assuming a solution of the form...
Hi, I'm reading through a paper and have come across what my tutor described as a 'theta function', however it seems to bear no resemblance to the actual 'theta function' I can find online. In the paper it reads:
\int^1_0 dz~\theta (s-\frac{4m^2}{z}-\frac{m^2}{1-z})
And apparently this...
Homework Statement
The steady state temperature distribution T(x,y) in a flat metal sheet obeys the partial differential equation:
\displaystyle \frac{\partial^2 T}{\partial x^2}+ \frac{\partial^2 T}{\partial y^2} = 0
Seperate the variables in this equation just like in the...
I'm having a tremendously hard time understanding the connection between macro and micro scale electrostatics and how (if?) they're described EQS boundary conditions. I understand that in a medium with mobile ions, an applied current or field will lead to the establishment of an electric double...
μ^{2}\frac{d^{2}u}{dx^{2}}+ae^{u}=0
Boundary conditions: u(-L)=u(L)=u_{0}
Solve by multiplying by \frac{du}{dx} and integrating in x
I know you have to use substitution, but I keep going in circles.
Hi All,
I was wondering if it is correct to say that a vanishing metric determinant is a necessary (but probably not sufficient) condition for a curvature singularity to exist at some point(s), or is one forced to construct the full Kretschmann scalar?
Cheers!
FD
Homework Statement
If a, b and c are nonzero distinct real numbers and c > 0. The even function given by:
f(x) = (ax + b)/(x + c)
is constant for -c < x < c and it's value is
(i) a + b; (ii) a + c; (iii) c; (iv) b; (v) a
Homework Equations
The Attempt at a Solution...
Laplace axisymmetric
$u(a,\theta) = f(\theta)$ and $u(b,\theta) = 0$ where $a<\theta<b$.
The general soln is
$$
u(r,\theta) = \sum_{n=0}^{\infty}A_n r^n P_n(\cos\theta) + B_n\frac{1}{r^{n+1}}P_n(\cos\theta)
$$
I am supposed to obtain
$$
u(r,\theta) = \sum_{n =...
I'm not sure how to solve this:
du/dt = 3 \frac{d^{2}u}{dx^{2}}
These are the conditions:
u(0,t)= -1
u(pi,t)= 1
u(x,0) = -cos 7x
Suggestion:
I should use steady state solution to get a homogeneous initial condition.
Starting with separtion of variables
u(x,t) = G(x)H(t)
And...
Homework Statement
"At 310K thermal energy kT=4.28x(10^-21). Use the equation you derived above (which I worked out to be E=(n²h²)/(8mL²) )to determine under which conditions quantum mechanics reduces to classical mechanics."
The hint was that "you need to find the value of mL² for which change...
Homework Statement
Using the definition of linearity to determine whether or not ech case is a linear homegeneous boundary condition:
i.) Uxx(0,y)=Ux(0,y)U(0,y)
ii.)Uy(x,0)=Ux(5,y)
Homework Equations
The Attempt at a Solution
I know Uxx(0,y)=Ux(0,y)U(0,y) is not linear...
Hello,
My problem is as follows:
I want to generate a series of 24 dimensional random numbers to act as the starting population for a genetic algorithm. These numbers need to fully span the space which is limited by a series of nonlinear boundary conditions.
The 24 dimensional vector is...
Hi
As we know, we have two kinds of Electromagnetic Boundary Conditions for interfaces in an electromagnetic problem.one is imposing the continuity of Bz and Hr and the other is applying the continuity of A(Magnetic Vector Potential) and the discontinuity of its derivative with respect to the...
I have already solved the main portions.
I have
$$
T(x,t) = \sum_{n = 1}^{\infty}A_n\cos\lambda_n x\exp(-\lambda_n^2t)
$$
The eigenvalues are determined by
$$
\tan\lambda_n = \frac{1}{\lambda_n}
$$
The initial condition is $T(x,0) =1$.
For the particular case of $f(x) = 1$, numerically...
Hello,
This was an exam question which I wasn't sure how to solve:
Suppose f is entire and |f(z)| \leq C(1+ |z|)^n for all z \in \mathbb{C} and for some n \in \mathbb{N}.
Prove that f is a polynomial of degree less than or equal to n.
I know that f can be expressed as a power series, but I'm...
I am really confused with the concept of Neumann Boundary conditions. For the simple PDE
ut=uxx for the domain from 0<=x<=1
I'm trying to use a ghost point (maintain a second order scheme) for the Neumann Boundary condition ux(0,t) = 0.
I understand that I can setup a scheme to...
Homework Statement
Show that sin(z) satisfies the condition. (Stated in the title)
Homework Equations
The Attempt at a Solution
f(z) = sin (z)
= sin (x + iy)
= sin x cosh y + i cos x sinh y
thus,
u(x,y)=sin x cosh y ... v(x,y)= cos x sinh y
du/dx = cos x...
Homework Statement
I'm working on some things to do with linearized gravitational radiation and I'm trying to justify the claim that in the Lorenz gauge, where \partial_{\nu}\bar{h}^{\mu\nu}=0 (1.1), we are able to impose the additional conditions A_{\alpha}^{\alpha}=0 (1.2) and...
Homework Statement
I have a general wave equation on the half line
utt-c2uxx=0
u(x,0)=α(x)
ut(x,0)=β(x)
and the boundary condition;
ut(0,t)=cηux
where α is α extended as an odd function to the real line (and same for β)
I have to find the d'alembert solution for x>=0; and show that in...
Hi,
it is known that given two subgroups H\subset G, and K\subset G of some group G, then we have that:
1) H, K are normal subgroups of G
2) H\cap K is trivial
are sufficient conditions for H and K to commute.
Moreover we have that:
H, K commute \Rightarrow H, K are normal.
In fact...
Homework Statement
we know that, every force systems can be generally replaced by a resultant force(R) and a couple(M) at a point O and the position of point O is optional.
but magnitude and direction of M is dependent to this point while magnitude and direction of R is independent.
In static...
Hi all,
I'm doing what should be a pretty simple problem, but some theory is giving me trouble.
Basically, in this problem I have a conducting sphere, surrounded by a thick insulating layer, and then vacuum outside that. I'm attempting to solve for the potential in the insulating layer by...
Hi,
Say I have this pde:
u_t=\alpha u_{xx}
u(0,t)=\sin{x}+\sin{2x}
u(L,t)=0
I know the solution for the pde below is v(x,t):
v_t=\alpha v_{xx}
v(0,t)=\sin{x}
v(L,t)=0
And I know the solution for the pde below is w(x,t)
w_t=\alpha w_{xx}
w(0,t)=\sin{2x}
w(L,t)=0
Would...
Hello there
I'd like to know if anyone has a proof of why the condition of symmetry or antisymmetry must be followed by a FIR filter, in order for it to have a linear phase response?
I've been pouring over this for an exam, and my initial question was what constitutes a linear phase...
Hi all.
Let's say I want to reproduce the support conditions for a beam. The easiest one I could think of is fixed end. Like I hammer an end of the beam into the wall. This represents fixed boundary condition. Likewise can anyone point out how to reproduce Simply supported end condition in...
Hello , i am trying to implement this algorithm for 2d grid.
1) i am not sure if my calculations are correct.
2 ) i don't understand how to return my final calculation ( how will i insert to the matrix i want (the 's' in this example) the new coordinates (xup,xdow,yup,ydown)).
I mean ...
The electric field in a cubical cavity of side length L with perfectly conducting walls
is
E_x = E_1 cos(n_1 x \pi/L) sin(n_2 y \pi/L) sin(n_3 z \pi/L) sin(\omega t)
E_y = E_2 sin(n_1 x \pi/L) cos(n_2 y \pi/L) sin(n_3 z \pi/L) sin(\omega t)
E_z = E_3 sin(n_1 x \pi/L) sin(n_2 y \pi/L)...
"Prove that the Bohr hydrogen atom approaches classical conditions when [. . .]"
Homework Statement
The problem and its solution are attached as ProblemSolution.jpg.
Homework Equations
E_k = chR/(n_k)^2
E_l = chR/(n_l)^2
ΔE = hc/λ
hc/λ = chR[1/(n_k)^2 – 1/(n_l)^2]
1/ λ = R[1/(n_k)^2 –...
I am trying to solve four coupled equations. Three of them are first order differential equations and the fourth is a algebraic one. The equations look something like this:
V_{l}(r) = f_{1}(r)W'_{l}(r) (1)
h''_{l} + f_{2}(r)h'_{l} + f_{3}(r)h_{l}(r) = U_{l}(r) (2)
f_{4}(r)U'_{l} +...
Homework Statement
Determine values of a, b, c in the formula ax^2+bx^2 +c that satisfy the conditions:
f(0)=0 // Limx->-1 F(x)=3 // limx->2 f(x)=6
The Attempt at a Solution
1.
F(0)=0 therefore x=0
so f(0)=a(0)^2+b(0)+c
so f(0)=c = 0
so c=0
2.
Lim f(x) = 3, x->-1
so...
Homework Statement
Solve the initial boundary value problem
u_{tt}=c^2u_{xx}
u(-a,t)=0,\quad u(a,t)=0,\quad u(x,0)=\sin(\omega_1 x)-b\sin(\omega_2x)
where a, b, \omega_1, \omega_2 are positive constants.
Homework Equations
d'Alembert's solution
The Attempt at a Solution...
Are there other ways of determining whether or not a function of a complex variable is analytic without using the Cauchy Riemann conditions? It seems for more complicated functions it's too difficult to decompose an arbitrary function into its real and imaginary parts, so it would be nice if...
Homework Statement
Find two lines in R3 in parametric form which satisfy the following conditions. Also, find the points on the lines which achieve the closest distance.
Conditions:
1. They are not parallel to any of the coordinate planes
2. They do not intersect and are not parallel
3. They...
second ODE, initial conditions are zeros at infinity!
I want to know the temperature profile of phase transition layer in the interstellar medium.
For stationary solution, the dimensionless differential equation I ended up with is
\frac{d^2T}{dx^2} = \frac{f(T)}{T^2} - \frac{1}{T}
where f(T)...
Homework Statement
It's a cilinder of mass M and radius R rolling without slipping and I'm asked to find the maximum value of the static friction coefficient for the cilinder to roll without slipping.
Homework Equations
Non-slip conditions:
\displaystyle v=\omega R
\displaystyle...
Long title, I know! :-p
Homework Statement
The heat of combustion of methane (\text{CH}_4) is 890.4 \ \text{kJ/mol} and the heat of capacity of \text{H}_2\text{O} is 75.2 \ \text{J}/\text{mol}\cdot\text{K} and that the heat capacity of \text{H}_2\text{O} is 37.7 \...
Hello everyone,
I have for loop in Mathematica. After every step Mathematica has new results calculated. I want to see only some results, those who met certain conditions, not results from all steps. Say, I have 10000 steps and I don't need all 10000 results, but only those that met certain...
Not really a specific problem, but just a general question:
Does anyone have any good references (preferably online) for solving E&M problems with this method? I'm using Griffith's Electrodynamics book for my class and I'm trying to get ready for a final. This is the only part I'm having...
Homework Statement
not an equation as such. new to this but i wanted to know what the conditions for nuclear fission are? other than high temperatue and pressure
Homework Equations
"state the conditions for fusion and hence explain why it has proved difficult to maintain a sustainable...
\check{}Homework Statement
Given the following data I need to find the oil formation volume factor at the saturation conditions;
A single flash separation of Angolan reservoir oil gave a stabilised (for stock tank) oil gravity of 37.19’ API and a gas gravity of 1.015. The GOR (gas oil...
Homework Statement
Show that the following three conditions of a metric space imply that d(x, y)=d(y, x):
(1) d(x, y)>=0 for all x, y in R
(2) d(x, y)=0 iff x=y
(3) d(x, y)=<d(x, z)+d(z, y) for all x, y, z in R
(Essentially, we can deduce a reduced-form definition of a metric space...
Homework Statement
Okay from what I have learned to prove that a series converges via the alternating test, you must prove the following conditions
Homework Equations
1) an > 0
2) lim an (n--> infinity) = 0
and
3) a(n+1) < an
The Attempt at a Solution
However recently I've been encountering...
Well i know real gases behave as ideal gas (almost) when pressure is low and temperature is high. I want to understand this - When pressure is low attractive forces in the gas moelcules will be stronger(as compared to high pressure) but the fast movement due to high temperature compensates it...