Jump to content

Draft:Random-key optimizers

From Wikipedia, the free encyclopedia
(Redirected from Draft:Random-Key Optimizers)


The Random-key optimizer (RKO) is a metaheuristic optimization algorithm that employs a continuous random-key representation to encode solutions. It is designed to solve combinatorial and continuous optimization problems by leveraging evolutionary and trajectory algorithm principles.

Overview

[edit]

RKO is based on the concept of random-key encoding, where solutions are represented as vectors of real numbers within a predefined range (typically [0,1]). These vectors are then decoded into feasible solutions using a problem-specific decoding function. The method is inspired by the Biased Random-Key Genetic Algorithm (BRKGA) but incorporates modifications to enhance efficiency and adaptability.

History

[edit]

The RKO method was introduced as a general-purpose optimization framework for solving complex decision-making problems. It builds upon the foundation of random-key genetic algorithms (RKGA), first introduced in the late 1990s, and extends their applicability by incorporating adaptive strategies and heuristic refinements.

Literaturereview

[edit]
  • Bean (1994): Random-Key Genetic Algorithms (RKGA)
  • Gonçalves and Almeida (2002), Gonçalves & Resende (2011): Biased Random-Key Genetic Algorithms (BRKGA)
  • Lin et al. (2010); Bewoor et al. (2017, 2018): Particle Swarm Optimization (PSO)
  • Garcia-Santiago et al. (2015): Harmony Search (HS)
  • Pessoa and Andrade (2018): Iterated Local Search (ILS), Iterated Greedy Search (IGS)
  • Andrade et al. (2019): ILS, Tabu Search (TS) and Simulated Annealing (SA)
  • Andrade et al. (2021): Implicit Path-Relinking (IPR)
  • Schuetz et al. (2022): Dual Annealing
  • Mangussi et al. (2023): SA, ILS, and Variable Neighborhood Search (VNS)
  • Chaves et al. (2024): Greedy Randomized Adaptive Search Procedure (GRASP)
  • Chaves et al. (2025): RKO Solver

Algorithm

[edit]

The general structure of the RKO involves the following steps:

  1. Initialization: Generate a population of random-key encoded solutions.
  2. Decoding: Convert random-key vectors into feasible solutions using a problem-specific decoding function.
  3. Evaluation: Assess the quality of each solution based on a predefined objective function.
  4. Search Process:
    1. Components:
      1. Initial Solutions: Generate a diverse set of random-key vectors to explore the solution space.
      2. Pool of Elite Solutions: Maintain a set of high-quality solutions for refinement and recombination.
      3. Shaking: Introduce perturbations to escape local optima and enhance exploration.
      4. Blending: Combine solutions to create new promising candidates.
      5. Local Search: Apply improvement procedures to refine candidate solutions.
      6. Metaheuristics: Incorporate additional optimization techniques (e.g., simulated annealing, VNS, ILS, etc.) to guide the search process.
  5. Termination: Repeat the process until a stopping criterion is met (e.g., time limit, maximum iterations, or convergence threshold).

Applications

[edit]

RKO has been applied to a variety of combinatorial optimization problems, including:

  • α-Neighborhood p-Median Problem (α-NpMP)
  • α-Neighborhood p-Center Problem (α-NpCP)
  • Node Capacitated Graph Partitioning Problem (NCGPP)
  • Tree Hub Location Problem (THLP)
  • Balanced Edge Partition Problem (BEPP)
  • Operating Room Scheduling Problem (ORSP)
  • Job Sequencing and Tool Switching Problem (SSP)
  • HEV Traveling Salesman Problem with Time Windows (HEVTSPTW)
  • Steiner Triple Covering Problem (STCP)
  • Traveling Thief Problem (TTP)
  • One-Dimensional Multi-Period Cutting Stock Problem (MPCSP)
  • Capacitated Vehicle Routing Problem (CVRP)
  • Portfolio Optimization

Recent Developments

[edit]
  • Continuous RKO algorithm for discrete optimization.
  • Multi-thread software framework with several RKOs that collaborate through solution sharing in a pool and local search.
  • Problem-independent framework—only a problem-dependent decoder needs to be implemented.
  • New adaptation of Nelder-Mead search for optimization in real n-dimensional unit hypercube.
  • Randomized Variable Neighborhood Descent (RVND) procedure integrating simple local search techniques.
  • Open-source software available on GitHub.
[edit]

References

[edit]
  • Andrade, C.E., Byers, S.D., Gopalakrishnan, V., Halepovic, E., Poole, D.J., Tran, L.K., & Volinsky, C.T. (2019). "Scheduling software updates for connected cars with limited availability." Applied Soft Computing, 82, 105575. doi:10.1016/j.asoc.2019.105575.
  • Andrade, C.E., Toso, R.F., Gonçalves, J.F., & Resende, M.G. (2021). "The multi-parent biased random-key genetic algorithm with implicit path-relinking and its real-world applications." European Journal of Operational Research, 289, 17–30. doi:10.1016/j.ejor.2019.11.037.
  • Bean, J.C. (1994). "Genetic algorithms and random keys for sequencing and optimization." ORSA Journal on Computing, 6, 154–160. doi:10.1007/s10729-008-9080-9.
  • Chaves, A.A., Resende, M.G.C., & Silva, R.M.A. (2024). "A random-key grasp for combinatorial optimization." Journal of Nonlinear & Variational Analysis, 8. doi:10.23952/jnva.8.2024.6.03.
  • Garcia-Santiago, C., Del Ser, J., Upton, C., Quilligan, F., Gil-Lopez, S., & Salcedo-Sanz, S. (2015). "A random-key encoded harmony search approach for energy-efficient production scheduling with shared resources." Engineering Optimization, 47, 1481–1496. doi:10.1080/0305215X.2014.
  • Gonçalves, J.F., & De Almeida, J.R. (2002). "A hybrid genetic algorithm for assembly line balancing." Journal of Heuristics, 8, 629–642. doi:10.1023/A:1020377910258.
  • Gonçalves, J.F., & Resende, M.G.C. (2011). "Biased random-key genetic algorithms for combinatorial optimization." Journal of Heuristics, 17, 487–525. doi:10.1007/s10732-010-9143-1.
  • Lin, T.L., Horng, S.J., Kao, T.W., Chen, Y.H., Run, R.S., Chen, R.J., Lai, J.L., & Kuo, I.H. (2010). "An efficient job-shop scheduling algorithm based on particle swarm optimization." Expert Systems with Applications, 37, 2629–2636. doi:10.1016/j.eswa.2009.08.015.
  • Londe, M.A., Pessoa, L.S., Andrade, C.E., & Resende, M.G. (2025). "Biased random-key genetic algorithms: A review." European Journal of Operational Research, 321, 1–22. doi:10.1016/j.ejor.2024.03.030.
  • Mangussi, A.D., Pola, H., Macedo, H.G., ao, L.A.J., Proença, M.P.T., Gianfelice, P.R.L., Salezze, B.V., & Chaves, A.A. (2023). "Meta-heurĂ­sticas via chaves aleatĂłrias aplicadas ao problema de localização de hubs em árvore." Anais do SimpĂłsio Brasileiro de Pesquisa Operacional, 25. doi:10.59254/sbpo-2023-174934.
  • Noronha, T.F., & Ribeiro, C.C. (2024). "Biased random-key genetic algorithms: A tutorial with applications." ACM International Conference Proceeding Series, 110–115. doi:10.1145/3665065.
  • Pessoa, L.S., & Andrade, C.E. (2018). "Heuristics for a flowshop scheduling problem with stepwise job objective function." European Journal of Operational Research, 266, 950–962. doi:10.1016/j.ejor.2017.10.045.
  • Schuetz, M.J., Brubaker, J.K., Montagu, H., van Dijk, Y., Klepsch, J., Ross, P., Luckow, A., Resende, M.G., & Katzgraber, H.G. (2022). "Optimization of robot-trajectory planning with nature-inspired and hybrid quantum algorithms." Physical Review Applied, 18, 054045. doi:10.1103/PhysRevApplied.18.054045.