ActiveLearningGaussianProcess

Permit re-training Gaussian Process surrogate model for active learning.

Description

The theory behind Gaussian Process (GP) is described in GaussianProcessTrainer. ActiveLearningGaussianProcess is slightly similar to the GaussianProcessTrainer class in that it trains a GP model. However, a key feature of ActiveLearningGaussianProcess is that it permits re-training the GP model on-the-fly during the active learning process. This means that the input the inputs and output data set sizes will be dynamic and re-training the GP can be performed several times as dictated by the learning (or acquisition) function during active learning.

Just like the GaussianProcessTrainer class, the GP model during active learning can be trained using either of the following options:

  • PETSc/TAO

    Relies on the TAO optimization library from PETSc. Several optimization algorithms are available from this library. Note that these algorithms perform deterministic optimization.

  • Adaptive moment estimation (Adam)

    Relies on the pseudocode provided in Kingma and Ba (2014). Adam permits stochastic optimization, wherein, a batch of the training data can be randomly chosen at each iteration.

Interaction between ActiveLearningMonteCarloSampler, ActiveLearningGaussianProcess, and ActiveLearningGPDecision

Figure 1: Schematic of active learning in Monte Carlo simulations with parallel computing. The interaction between the three objects, ActiveLearningMonteCarloSampler, ActiveLearningGaussianProcess, and ActiveLearningGPDecision, is presented.

Usage of active learning

Please refer to ActiveLearningGPDecision on a detailed description on using active learning.

Input Parameters

  • covariance_functionName of covariance function.

    C++ Type:UserObjectName

    Unit:(no unit assumed)

    Controllable:No

    Description:Name of covariance function.

Required Parameters

  • batch_size0The batch size for Adam optimization

    Default:0

    C++ Type:unsigned int

    Unit:(no unit assumed)

    Controllable:No

    Description:The batch size for Adam optimization

  • execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

    Default:TIMESTEP_END

    C++ Type:ExecFlagEnum

    Unit:(no unit assumed)

    Options:NONE, INITIAL, LINEAR, NONLINEAR_CONVERGENCE, NONLINEAR, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM

    Controllable:No

    Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

  • filenameThe name of the file which will be associated with the saved/loaded data.

    C++ Type:FileName

    Unit:(no unit assumed)

    Controllable:No

    Description:The name of the file which will be associated with the saved/loaded data.

  • learning_rate0.001The learning rate for Adam optimization

    Default:0.001

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:The learning rate for Adam optimization

  • num_iters1000Tolerance value for Adam optimization

    Default:1000

    C++ Type:unsigned int

    Unit:(no unit assumed)

    Controllable:No

    Description:Tolerance value for Adam optimization

  • prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

    C++ Type:MaterialPropertyName

    Unit:(no unit assumed)

    Controllable:No

    Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

  • show_every_nth_iteration0Switch to show Adam optimization loss values at every nth step. If 0, nothing is showed.

    Default:0

    C++ Type:unsigned int

    Unit:(no unit assumed)

    Controllable:No

    Description:Switch to show Adam optimization loss values at every nth step. If 0, nothing is showed.

  • standardize_dataTrueStandardize (center and scale) training data (y values)

    Default:True

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Standardize (center and scale) training data (y values)

  • standardize_paramsTrueStandardize (center and scale) training parameters (x values)

    Default:True

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Standardize (center and scale) training parameters (x values)

  • tune_parametersSelect hyperparameters to be tuned

    C++ Type:std::vector<std::string>

    Unit:(no unit assumed)

    Controllable:No

    Description:Select hyperparameters to be tuned

  • tuning_maxMaximum allowable tuning value

    C++ Type:std::vector<double>

    Unit:(no unit assumed)

    Controllable:No

    Description:Maximum allowable tuning value

  • tuning_minMinimum allowable tuning value

    C++ Type:std::vector<double>

    Unit:(no unit assumed)

    Controllable:No

    Description:Minimum allowable tuning value

  • use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

Optional Parameters

  • allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

  • control_tagsAdds user-defined labels for accessing object parameters via control logic.

    C++ Type:std::vector<std::string>

    Unit:(no unit assumed)

    Controllable:No

    Description:Adds user-defined labels for accessing object parameters via control logic.

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:Yes

    Description:Set the enabled status of the MooseObject.

  • execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

    Default:0

    C++ Type:int

    Unit:(no unit assumed)

    Controllable:No

    Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

  • force_postauxFalseForces the UserObject to be executed in POSTAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in POSTAUX

  • force_preauxFalseForces the UserObject to be executed in PREAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREAUX

  • force_preicFalseForces the UserObject to be executed in PREIC during initial setup

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREIC during initial setup

  • use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Advanced Parameters

References

  1. D. P. Kingma and J. Ba. Adam: a method for stochastic optimization. arXiv:1412.6980 [cs.LG], 2014. URL: https://doi.org/10.48550/arXiv.1412.6980.[BibTeX]