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 does it mean for a solution to be degenerate?
For example, when applying the stepping stone method to the basic feasible solution of a transportation problem, the number of occupied cells needs to be m+n-1 for the solution to not be degenerate. Where m= no. of rows, n= no. of columns. What does…
Nia
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Optimize a simple trading problem
I am developing a simple resource trading game set in space for fun. The board is a two dimensional representation of a solar system (roughly similar to this image).
The game mechanics are as follows:
Planets orbit a sun at different speeds…
mritz_p
- 143
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Linear programming of sperner lemma
How can you formulate the 2-D proof of Sperner lemma as a linear programming problem?
I know that you have to divide the triangle up into smalled triangles with the original triangle having vertices labelled 0,1,2. However, I have no idea what to…
Kyle C
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Operations research invert pyramid problem in minimum steps mathematical intutive solution to reach optimal solution
A (two-dimensional) pyramid is constructed in four layers: The bottom layer consists of (equally spaced) dots 1, 2, 3, and 4; the next layer includes dots 5, 6, and 7; the following layer has dots 8 and 9; and the top layer has dot 10. You want to…
Akansha Banerjee
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How to subtract a common path cost?
I have a simple pickup and delivery (PDP) model operating on a service provider that has multiple locations for providing service. My decision variables and parameters are as follows:
$\delta_{i,j}^d$: a binary variable indicating whether taxi…
yaodao vang
- 197
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Shortest path to sort a list through item exchanging
What is the shortest path to sort a list through item exchanging?
Recently, I met a math problem. I'd like to find an apporach to convert a list to ordered list by item exchanging with corresponding costs.
In short, the problem is as follows:
For a…
Zong
- 11
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Linear constraint
I found this video extremely helpful to determine the floorplanning constraints.
The first two constraints (i) make sure the modules are within the feasible floorplan; the subsequent four constraints (ii) make sure that no two modules overlap, and…
user818406
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2 answers
Where does the fourth step come from?
I'm talking about the step after $x(x-1) = \sqrt\frac{\mu}{3}$.
Max
- 155
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Infinite loop in column generation algortihm
I have to program the following:
Input:
I have k commodities that have to go from place i to j with a certain demand
There are n nodes and the cost for traveling one piece between the nodes i and j
Each arc has a given maximal capacity
The…
Lotte Laat
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Demand for operations research in industry
I want to know how much demand there is for OR in the commercial world, and understand the relevance and prevalence of OR.
Is the airline industry the place where this technique is applied the most? What other areas would OR be in demand from your…
Will Kim
- 277
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1 answer
"Sufficient and necessary" big M constraint
I have been given a problem to translate into a linear model.
The relevant part to my question is: we're given $ \{{ 1,..., m}\}$ robots to work on $\{ 1,...,n \} $ products
each robot $i$ takes time $a_{ij}$ to complete his task on product…
Lilla
- 2,099
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linearization Technique_operations research
How can I linearize the following constraint?
(X-Y)*(i-p)=<0
where, x and y and i and p are positive variables.
mahdi
- 19
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How do you call the operation of counting the number of euclidian division until the denominator is lower than the remainder?
I was looking for the minimum size of a base35 secret_key to be able to generate at least 1,000,000 secret key.
The result is 35*35*35*35 = 1500625
How do you call this operation of counting the number of euclidian division until the denominator is…
Natim
- 155
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What to do if we don't get m+n-1 basic variables in stepping stone method?
In stepping stone method (for transportation model), it is one of the requirements that number of basic variables must be m+n-1, where m and n are no of rows and columns respectively.My question is: How to proceed if we do not get m+n-1 basic…
Khan
- 11
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1 answer
Is Pareto efficiency (Pareto Optimal) a part of Operation Research?
I know that Pareto efficiency (Pareto Optimal) is an economic concept that helps for multi-criteria decision making process. My doubt is whether any decision process is a part of Operation Research. In fact, I know that OR is a discipline that deals…
UserAb
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