5th Seminar; Speaker: Geoffrey De Smet, JBoss OptaPlanner Lead at Red Hat Software Date: May 14, 2013 Time: 10 a.m. EST (UTC -5) Title: Part 2: Construction heuristics and metaheuristics (Part 1) Abstract: In this session, I’ll cover exact heuristics (brute force, depth first search), construction heuristics (first fit, first fit decreasing) and metaheuristics (hill climbing, tabu search, simulated annealing, late acceptance) with clear, simple, understandable diagrams. I’ll illustrate their results with OptaPlanner benchmark reports. [...]

4th Seminar; Speaker: Prof. Ian Frommer, Mathematics Dept., US Coast Guard Academy, New London, CT, USA Date: April 24, 2013 Time: 10 a.m. EST (UTC -5) – Check your local time Title: Project-Based Learning in Operations Research and Sustainability Abstract: Operations research (O.R.) is playing an increasingly important role in addressing sustainability challenges such as green-house gas reduction and renewable energy use. In this talk, quantitative sustainability projects that can be utilized in undergraduate courses [...]

I remember that I was playing Resident Evil, after everybody sleep, in fear for hours. Although I really don’t like the “zombie” idea, it’s a popular phenomena that people want to be prepared for a zombie outbreak. I am not sure about its likelihood, but obviously it’s popular among generations and some people may be happy if it really happens. Well, what is the deal with zombies in an Operations Research blog? Here it comes: [...]

A few weeks ago John Foreman wrote “I think if more hackers knew about linear programming, they’d like it. Big M constraints are the hackiest things I know.” Afterwards, I read that Internet slows globally after biggest cyber-attack of the history, although it seems my Internet connection is faster nowadays :)  Then I thought; really, where is operations research in this fight against hackers to defend network security? Obviously, all topics related to algorithms and [...]

As a PhD student, I often use [R] for writing assignments, quizzes, reports and even for my thesis.  has a unique way to convert any piece of  messy information into an elegant text. Perhaps, it is the most used typesetting program in academia. You know how it is difficult to continue your work outside, on top of that  may not available in the computer you are using. If you are thinking that you are out of luck in [...]

We are very pleased to announce a competition track at MISTA 2013. The competition is based around multi-mode resource-constrained multi-project scheduling problem (MRCMPSP) in which multiple projects have to be scheduled, while taking into account the availability of local and global resources. The competition has a cash prize associated with it. More details can be seen at http://allserv.kahosl.be/mista2013challenge/ Important dates 4th of April 2013 Deadline for registration and end of qualification phase 30th of April [...]

The mission of OptaPlanner (renamed from Drools Planner) is to enable normal JavaTM programmers to solve NP-complete problems in production. This open source project brings intelligent heuristic and metaheuristic algorithms mainstream by implementing them in a stable, scalable, reusable and easy to use manner. It’s used in production all over the world. Although OptaPlanner is focused on production use – and this requirement does take up a lot of my time – it’s very comfortable [...]

3rd Seminar; Speaker: Geoffrey De Smet, JBoss Drools Planner Lead at Red Hat Software Date: January 31, 2013 Time: 10 a.m. EST (UTC -5) – Check your local time Title: Score Design for (Meta)heuristics Abstract: In this session, I’ll cover score design (pos/neg, weights, levels, pareto) with clear, simple, understandable diagrams. I ‘ll talk about some of the challenges involved in these techniques (rounding, folding, score traps). I ‘ll illustrate this with some Drools Planner examples. [...]

Undoubtedly one of the most popular and widely used simulation software, ARENA is a powerful tool for modeling complex systems. Based on the complexity of the system you are modeling, you need to take a long run to eliminate initial bias in the system or take several replications to get a more accurate estimation. In this post, I will briefly show the running options in ARENA to shorten your running time. I am using ARENA [...]

We communicate with words. Each word has its own history, also each word triggers different concepts in everybody’s mind. But we are not fully aware of this. For an example you can watch this part of Douglas Hofstadter’s talk. In this post I will list some popular IE/OR terms. It is interesting to see the change in the meaning of the words. Please feel free to suggest words. I started with oldest words, highlighted the [...]