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Geoffrey De Smet
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Geoffrey De Smet

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Works in past releases, such as 6.0, already :)
 
How to use a #Drools decision table to enable normal users to define the soft score constraints themselves in #OptaPlanner .
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Given an planning or optimization problem, how big is the search space? Can we hope to enumerate every possible solution, looking for the optimal solution? Let’s calculate the search space of a few use cases.

#optaplanner
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Java SE 8 was released yesterday. Traditionally, every new major JRE version comes with a free performance boost. Do we get another free lunch? And how big is the gain this time?

I've benchmarked it:
http://www.optaplanner.org/blog/2014/03/20/HowMuchFasterIsJava8.html

#openjdk #java8 #java
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Intresting. I am doing a 30second warmup, so I ignore any startup gains.
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I am adding Depth First Brand&Bound to #OptaPlanner 6.1.0.Beta2. Here are the results of a run on very small datasets, limited to 2 minutes of running time, compared it with Tabu Search. Starting from 8 computers and 24 processes (the 7th instance), B&B can not visit all its nodes before hitting the time limit.
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Geoffrey De Smet

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If the cities would be partitioned into 4 random distinct sets, we'd get 4 tours covering the whole surface... I am not sure how to merge those (there are some difficult techniques IIRC). And it gets worse if asymmetric arcs or time windows are involved.

+Frank Nestel I use the term layman term "planning problem", but a more precise term is NP-hard optimization problems.
This relates to the PvsNP question: for these kind of problems there is probably no polynomial time solution, which more or less implies that we can't split up a problem and solve each piece independently in order to solve the problem itself.
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The BRMS 6 maven repository has landed :)
 
Red Hat JBoss BRMS & JBoss BPM Suite 6.0.1 Maven Repository POM Configuration
The new JBoss BRMS & JBoss BPM Suite was released yesterday bringing a lot of new improvements, fixes, and features. One of the most exciting is the availability of a public facing maven repository based on these two products. We will provide you here with ...
The new JBoss BRMS & JBoss BPM Suite was released yesterday bringing a lot of new improvements, fixes, and features. One of the most exciting is the availability of a public facing maven repository based on these two products...
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New optimization algorithm for #OptaPlanner 6.1.0.Beta2: Branch And Bound.

It finds the optimal solution. It scales better than Brute Force, but it still scales poorly, especially compared to a Construction Heuristic + Local Search approach (which can handle tens of thousands of variables and billions of potential constraint matches).
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Geoffrey De Smet

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Easier said then done :)
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Geoffrey De Smet

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Have him in circles
694 people
Brian Fitzpatrick's profile photo
Eva Robbrecht's profile photo
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OptaPlanner lead
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OptaPlanner lead
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I am the lead for OptaPlanner (java, open source) and I work for Red Hat.


OptaPlanner optimizes business resource usage. Every organization faces planning problems: provide products or services with a limited set of constrained resources (employees, assets, time and money). OptaPlanner optimizes such planning to do more business with less resources.

OptaPlanner is a lightweight, embeddable planning engine written in Java™. It helps normal Java™ programmers solve constraint satisfaction problems efficiently. Under the hood, it combines optimization heuristics and metaheuristics with very efficient score calculation.

OptaPlanner is open source software, released under the Apache Software License. It is 100% pure Java™, runs on any JVM and is available in the Maven Central Repository too.

For more information, visit http://www.optaplanner.org
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