Benchmarking AEM problems with various DL structures

This repository stores implemention of paper Benchmarking Data-driven Surrogate Simulators for Artificial Electromagnetic Materials

It includes a suit of AEM data set benchmarks along with implementation of various ready-to-use deep learning architectures (MLP, Transformer, MLP-Mixer) for scientific computation problem and a handful of utility functions.

Data Sets

Schematics of geometry in three physical problems. (a) Infinite array of all-dielectric metasurfaces consists of four elliptical-resonators supercells. (b) A nanophotonic particle consists of four layers. (c) The three-layers color filter design.

Requirements

Package	Version
Python	>=3.7
Pytorch	>= 1.3.1
Numpy	>=1.17.4
Pandas	>=0.25.3
Tensorboard	>=2.0.0
Tqdm	>=4.42.0
Sklearn	>=0.22.1
Matplotlib	>= 3.1.3
einops	>= 0.3.0
seaborn	>= 0.11.2

Features

• Access to various ADM data sets
• Off-the-shelf implementation of MLP, Transformer and MLP-Mixer with high individuality
• Utilities for data preprocessing and preparation for downstream deep learning tasks
• Utilities for plotting and easy analysis of results

Usage

Access to Data Sets

1. ADM Data Set. Please download and unzip from the Repository.
2. Particle Data Set. Please download and unzip from the Repository.
3. Color Data Set. Please download and unzip from the Repository.

Download Pre-trained Models

1. MLP: Please download and unzip from the folder.
2. Transformer: Please download and unzip from the folder.
3. MLP-Mixer: Please download and unzip from the folder.

Install Package

pip install AEML

Loading data and Splitting

Loading benchmark datasets described in Section 4.1 of the paper

ADM refers to the All-dielectric metasurface dataset. Particle dataset refers to the Nanophotonic Particle dataset. The Color dataset refers to the Color filter dataset. The specification of each dataset is provided in the table below:

Dataset	D_in	D_out	Sub_area	Simulations	Simulation CPU time
All-dielectric metasurfac	14	2001	Metamaterials	60,000	7 months
Nanophotonic particle	8	201	Nanophotonics	50,000	11 hours
Color	3	3	Optical waveguide	100,000	-

Loading your own benchmark dataset into the framework

Although we used AEM dataset for benchmarking, this suite is open and easily adaptable to a wide range of applications in the scientific computing community. To test your own custom dataset, simply normalize (or not, your choice, our loader would not normalize your dataset) and put your dataset into the Custom folder with the format: data_x.csv, data_y.csv where each file contains the input and output of the application. The shape should be [#Simulations, Dim_x] and [#Simulations, Dim_y] and separated by comma. Note that there should not be any header in the csv.

import AEML
from AEML.data import ADM, Particle, Color, load_custom_dataset

# Load our pre-defined dataset
train_loader, test_loader, test_x, test_y =ADM/Particle/Color(normalize=True/False, batch_size=1024)    # Loading the ADM dataset

# Or, load prepare your own dataset here
# train_loader, test_loader, test_x, test_y = load_custom_dataset()

Loading Models with configurable hyper-paramters and making prediction

Architectures of various DL structures implementd

As dscribed in section 5 in the paper, the architectures are modified slightly from the original Mixer and Transformer models to fit our scientific computing background.

Model hyper-parameter adjustment

from AEML.models.Mixer import DukeMIXER
from AEML.models.MLP import DukeMLP
from AEML.models.Transformer import DukeTransformer

# 1. Defining all the models here (We highly recommend training the models one by one due to GPU RAM constraints
#MLP:
model = DukeMLP(dim_g=3, dim_s=3, linear=[500, 500, 500, 500, 500, 500], skip_connection=False, skip_head=0, dropout=0, model_name=None)

#Transformer:
model= DukeTransformer(dim_g, dim_s, feature_channel_num=32, nhead_encoder=8, 
                        dim_fc_encoder=64, num_encoder_layer=6, head_linear=None, 
                        tail_linear=None, sequence_length=8, model_name=None, 
                        ckpt_dir=os.path.join(os.path.abspath(''), 'models','Transformer'))
#Mixer:
model = DukeMIXER(dim_g, dim_s, mlp_dim=500, patch_size=10, mixer_layer_num=6,
                embed_dim=128, token_dim=128, channel_dim=256, 
                mlp_layer_num_front=3, mlp_layer_num_back=3)

# 2. Model training code

#MLP:
model.train_(train_loader, test_loader, epochs=500, optm='Adam', weight_decay=1e-4,
            lr=1e-4, lr_scheduler_name='reduce_plateau', lr_decay_rate=0.2, eval_step=10,
            stop_threshold=1e-7)

#Transformer:
model.train_(train_loader, test_loader, epochs=500, optm='Adam', reg_scale=5e-4, lr=1e-3, 
                        lr_schedueler_name='reduce_plateau',lr_decay_rate=0.3, eval_step=10)

#Mixer:
model.train_(train_loader, test_loader, epochs=500, optm='Adam', weight_decay=1e-4,
            lr=1e-4, lr_scheduler_name='reduce_plateau', lr_decay_rate=0.2, eval_step=10,
            stop_threshold=1e-7)

# Loading the model you just trained or hypersweeped or our provided pretrained model if 
# you don't want to train it or just want to reproduce our result, only choose one between these 2
model.load_model(pre_trained_model='Particle'\'AMD'\'Color'\None, 
                model_directory='YOUR_MODEL_DIRECOTRY')

# Model inference code: Give it X, output Y
pred_Y = model(test_X)

# Model evaluation code: Give it test_X, test_Y, output MSE and generate a plot of MSE histogram in \data
MSE = model.evaluate(test_x, test_y, save_output=False, save_dir='data/')

Performance of various DL structures on benchmark ADM data sets

Relative size of our pre-trained networks

Support

Please file an issue here.

License

The project is licensed under the MIT license.

Please cite this work if some of the code or datasets are helpful in your scientific endeavours. For specific datasets, please also cite the respective original source(s), given in the preprint.