Operations Research, sometimes known as Management Science or Decision Science, is the discipline of applying appropriate analytical methods to help those who run organisations make better decisions.
Questions tagged [operations-research]
794 questions
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What's the state-of-the-art for p-median problem?
I am reading work on the famous p-median problem, like A survey of metaheuristic approaches. I understand the Greedy heuristic is often taken as the baseline algorithm.
I want know what is the state-of-the-art algorithm for p-median problem. If I…
Jill Clover
- 4,787
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What is minimum transportation cost by Vam method?
According to table in image (at the bottom)
If an arrival of VVIP blocks the traffic from branch I to customer C and D and from II to customer D and E. What is minimum transpotation cost by vam method.
My textbook answer is 221. But I am not…
T.Noor
- 129
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problem on checking for basic solution
I am stuck in the following problem:
maximize z=$x_1+2x_2+3x_3-4x_4$
subject to
$2x_1+3x_2-x_3-x_4=15$
$6x_1+x_2+x_3-3x_4=21$
$8x_1+2x_2+3x_3-4x_4=30$
$x_1,x_2,x_3,x_4$$\ge0$
then,$x_1=4,x_2=3,x_3=0,x_4=2$ is
(a) an optimal solution
(b)a degenerate…
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1 answer
How to linearize the following if-then constraint?
For my class in OR I have to linearize the following constraint:
IF ($x_1$ = 0 AND $x_2$ = 0) THEN $x_3$ = 0.
My first idea was to make use of some binary variables ($y_1$, $y_2$ and $y_3$) and some sufficiently large integers ($M_1$ and…
wreitsma
- 57
0
votes
1 answer
Can every precedence table be represented as an "activity on arc" activity network
I have the precedence table
Activity | depends on
A | -
B | -
C | -
D | A,B
E | B,C
F | A,C
And I want to write it as an activity on arc network
So far I have:
1--D--4
/|
A ^
/ |
0-B-2
…
James K
- 1,255
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1 answer
Objective function: linear programming
The following simultaneous nonlinear equations are to be solved:
$$y=e^x$$
$$y=x(1+x)$$
Define an objective function that can be maximized to obtain a solution to these equations.
Sketch x vs F(x) and identify the optimal solution (x*)…
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Simplex Method, which step is wrong?
Question:
$$\text{Maximize } z=2x_1-6x_2$$
Subject to,
$$-x_1-x_2-x_3\le-2$$
$$2x_1-x_2+x_3\le1$$
$$x_1,x_2,x_3\ge0$$
My work:
$-2x_1+6x_2+z=0$
Then,
${R2\over2}\Rightarrow R2_{new}$,
$R2_{new} + R1\Rightarrow R1_{new}$,
$2\cdot R2_{new}+…
Neuer
- 49
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1 answer
It's regarding operation research cost model, can you please tell me how to solve this
An author has option of either publishing his novel himself or through a publisher . Publisher is offering him $ 20000$ for signing contract.
If novel is successful it would Sell 20000 copies , if not then 10000 copies. Publisher pays $1$ as…
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1 answer
I am confused in infeasible and optimal solution
My question is: is optimal solution exsit in case of infeasibilty?
I am confused becz in my book ..it said..optimal solution exist but artificial variable not eliminated from table(infeasible case).
But its definition of optimal solution that it…
-3
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2 answers
Ratio vs. Difference
The naturals: $\{1, 2, 3, ... \}$
$2 - 1 = 1$ and $\frac{2}{1} = 2$
$3 - 2 = 1$ and $\frac{3}{2} = 1.5$
$4 - 3 = 1$ and $\frac{4}{3} = 1.333...$
.
.
.
$167834632 - 167834631 = 1$ and $\frac{167834632}{167834631} = 1.000000006...$
$\displaystyle…
Agent Smith
- 951
-3
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2 answers
optimization method to solve a problem
A small petroleum company owns two refineries. Refinery 1 costs \$20,000 per day to
operate, and it can produce 400 barrels of high-grade oil, 300 barrels of medium-grade oil,
and 200 barrels of low-grade oil each day. Refinery 2 is newer and more…
Nina Bosch
- 17