Improving Memory for Optimization and Learning in Dynamic Environments

Abstract

Many problems considered in optimization and artificial intelligence research are static: information about the problem is known a priori, and little to no uncertainty about this information is presumed to exist. Most real problems, however, are dynamic: information about the problem is released over time, uncertain events may occur, or the requirements of the problem may change as time passes. One technique for improving optimization and learning in dynamic environments is by using information from the past. By using solutions from previous environments, it is often easier to find promising solutions in a new environment. A common way to maintain and exploit information from the past is the use of memory, where solutions are stored periodically and can be retrieved and refined when the environment changes. Memory can help search respond quickly and efficiently to changes in a dynamic problem. Despite their strengths, standard memories have many weaknesses which limit their effectiveness. This thesis explores ways to improve memory for optimization and learning in dynamic environments. The techniques presented in this thesis improve memories by incorporating probabilistic models of previous solutions into memory, storing many previous solutions in memory while keeping overhead low, building long-term models of the dynamic search space over time, allowing easy refinement of memory entries, and mapping previous solutions to the current environment for problems where solutions may become obsolete over time. To address the weaknesses and limitations of standard memory, two novel classes of memory are introduced: density-estimate memory and classifier-based memory. Density-estimate memory builds and maintains probabilistic models within memory to create density estimations of promising areas of the search space over time.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 2011
Accession Number
ADA560676

Entities

People

  • Gregory J. Barlow

Organizations

  • Carnegie Mellon University

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Algorithms
  • Artificial Intelligence
  • Artificial Intelligence Software
  • Computational Science
  • Computer Programs
  • Control Systems
  • Evolutionary Algorithms
  • Genetic Algorithms
  • Job Shop Scheduling
  • Machine Learning
  • Models
  • Optimization
  • Particle Swarm Optimization
  • Probabilistic Models
  • Scheduling (Production)
  • Self Organizing Systems
  • United States

Fields of Study

  • Computer science

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Parallel and Distributed Computing.
  • Systems Analysis and Design

Technology Areas

  • AI & ML
  • AI & ML - Machine Learning Algorithms
  • Space