Operations Research Methods
Fall 2012





December 10, 2012: Virtual Office Hours #12: I Love Lucy Queueing

In this video, we take the problem of Lucy and Ethel in the chocolate factory, wrapping and eating chocolates. We model the problem as a queueing system and calculate the associated parameters.

Details:
Motivation and laughs: Start at beginning
Word Problem to solving Queueing System: Start at about 1:00

I Love Lucy Queueing from Sarah Nurre on Vimeo.




November 28, 2012: Virtual Office Hours #11: MMult in Excel

In this video, we take a one step probability transition matrix and calculate the two step and three step matrices by properly using the mmult function in Excel, which does matrix multiplication.

mmult in Excel from Sarah Nurre on Vimeo.




November 28, 2012: Virtual Office Hours #10: Markov Chain Steady State Equations

In this video, we go through a Markov Chain Example. Specifically, we formulate the steady state equations. We then use Excel solver to solve the series of equations.

Details:
Steady state equations: Start at beginning
Solving equations using excel: Start at about 3:39

Steady State Markov Equations from Sarah Nurre on Vimeo.




November 12, 2012: Virtual Office Hours #9: Goal Programming

In this video, we go through a goal programming problem example. We take a problem with 3 different goals and weight any deviations from these goals appropriately. We then solve the problem in order to see which goals we can meet.

Details:
Goal Programming Formulation: Start at beginning
Linear Programming Formulation and Deviations: Start at about 2:11
Solving with Excel: Start at about 11:50
Penalty Weights: Start at about 14:50

Video Tutorial #9 Goal Programming from Sarah Nurre on Vimeo.




November 6, 2012: Virtual Office Hours #8: Branch and Bound

In this tutorial, we take an integer programming problem and solve it using Branch and Bound.

Video Tutorial #8 Branch and Bound from Sarah Nurre on Vimeo.




October 29, 2012: Virtual Office Hours #7: Efficient Frontier

Hurricane Sandy is almost here and you need to staff the power company's call center in order to handle the influx of calls. In this tutorial, we create the efficient fronter of points for this problem with conflicting objectives of maximizing responsiveness (short customer wait time, e.g. on hold) and maximizing efficiency (call center workers always working).

Video Tutorial #7 Efficient Frontier from Sarah Nurre on Vimeo.




October 10, 2012: Virtual Office Hours #6: Integer Programming

In this tutorial, we take a word problem about farmers markets and formulate it as an integer program (IP). We then show how to solve this IP in Excel.

Details:
Word Problem to IP: Start at beginning
IP Solved with Excel: Start at about 13:35

Virtual Office Hours #6: Integer Programming from Sarah Nurre on Vimeo.




September 27, 2012: Virtual Office Hours #5: Shortest Path Problem

In this tutorial, we take an awesome 90's country song as our example and solve the shortest path problem to the 'old Georgia Pine'. The approach I take is still Dijkstra's algorithm but I show it in a slightly different manner.

Details:
Motivation: Start at beginning
Start of problem: Start at about 0:48

Shortest Path Problem based on Meet in the Middle from Sarah Nurre on Vimeo.




September 14, 2012: Virtual Office Hours #4: Two Phase Method

In this tutorial, we will take a linear program (LP) with some equality constraints and solve it using the Two Phase Simplex Method.

Video Tutorial #4: The Two Phase Method from Sarah Nurre on Vimeo.




September 14, 2012: Virtual Office Hours #3: Tabular Simplex Method

In this tutorial, we will take a linear program (LP) and solve it using the tabular simplex method. We will be using the excel document that Professor Sharkey presented in class on Thursday, September 13, 2012 for our calculations. This document is available on LMS.

Details:
LP to Augmented LP: Start at beginning
Solving using Simplex: Start at 2:23

Video Tutorial #3: Tabular Simplex from Sarah Nurre on Vimeo.




September 4, 2012: Virtual Office Hours #2: The Supermarket Sweep Problem

In this tutorial, we take the Supermarket Sweep game show and formulate it as a linear program. We then show how to use Excel Solver to find the optimal solution to the model in order to win the game.

**I am working on a way to get this video to embed in HD so it is not as blurry. Hopefully it will be fixed by Monday September 17th.

Details:
Word Problem to LP: Start at beginning
LP to Excel: Start at about 6:49
Excel Data to Solver: Start at 12:50

Video Tutorial #2: Supermarket Sweep Problem from Sarah Nurre on Vimeo.




August 31, 2012: Virtual Office Hours #1: The Cat Diet Problem

In this tutorial, we go through a linear programming example similar to the woodworking problem done in class. We will start with a word problem and formulate it as a linear program (LP) using equations. We will then graph the problem, and show a new way of finding the optimal solution.

Details:
Word Problem to LP: Start at beginning
LP to Graph: Start at about 5:23
Graph to Optimal Solution: Start at 8:40

Virtual Office Hours 1: The Cat Diet Problem from Sarah Nurre on Vimeo.