The CO2 capture efficiency in solvent-based carbon capture systems (CCSs) critically depends on the gas-solvent interfacial area (IA), making maximization of IA a foundational challenge in CCS design. While the IA associated with a particular CCS design can be estimated via a computational fluid dynamics (CFD) simulation, using CFD to derive the IAs associated with numerous CCS designs is prohibitively costly. Fortunately, previous works such as Deep Fluids (DF) (Kim et al., 2019) show that large simulation speedups are achievable by replacing CFD simulators with neural network (NN) surrogates that faithfully mimic the CFD simulation process. This raises the possibility of a fast, accurate replacement for a CFD simulator and therefore efficient approximation of the IAs required by CCS design optimization. Thus, here, we build on the DF approach to develop surrogates that can successfully be applied to our complex carbon-capture CFD simulations. Our optimized DF-style surrogates produce large speedups (4000x) while obtaining IA relative errors as low as 4% on unseen CCS configurations that lie within the range of training configurations. This hints at the promise of NN surrogates for our CCS design optimization problem. Nonetheless, DF has inherent limitations with respect to CCS design (e.g., limited transferability of trained models to new CCS packings). We conclude with ideas to address these challenges.

Low-power brain-inspired hardware systems have gained significant traction in recent years. They offer high energy efficiency and massive parallelism due to the distributed and asynchronous nature of neural computation through low-energy spikes. One such platform is the IBM TrueNorth Neurosynaptic System. Recently TrueNorth compatible representation learning algorithms have emerged, achieving close to state-of-the-art performance in various datasets. An exception is its application in temporal sequence processing models such as recurrent neural networks (RNNs), which is still at the proof of concept level. This is partly due to the hardware constraints in connectivity and syn-aptic weight resolution, and the inherent difficulty in capturing temporal dynamics of an RNN using spiking neurons. This work presents a design flow that overcomes the aforementioned difficulties and maps a special case of recurrent networks called Long Short-Term Memory (LSTM) onto a spike-based platform. The framework is built on top of various approximation techniques, weight and activation discretization, spiking neuron sub-circuits that implements the complex gating mechanisms and a store-and-release technique to enable neuron synchronization and faithful storage. While many of the techniques can be applied to map LSTM to any SNN simulator/emulator, here we demonstrate this approach on the TrueNorth chip adhering to its constraints. Two benchmark LSTM applications, parity check and Extended Reber Grammar, are evaluated and their accuracy, energy and speed tradeoffs are analyzed.

Image features can be learned and subsequently used for reconstruction and classification tasks in the fields of machine learning and computer vision. In this work, we propose image reconstruction using Convolutional Sparse Coding (CSC) on IBM's TrueNorth Neuromorphic computing system. CSC explicitly models local interactions through the convolution operations. Convolutional kernels define a dictionary and Sparse Feature Maps (SFMs) that are generated through a training process. The images are reconstructed with convolutional operations on SFMs and respective kernels. In this paper, we report on experimental results demonstrating promising sparse reconstructions on the IBM Neuromorphic TrueNorth hardware for two different benchmarks: MNIST and CIFAR-10. It is noted that this is the first ever important step towards convolutional sparse coding on neuromorphic hardware.

The problems of Artificial intelligence (AI) naturally maps to NP-hard optimization problems. This trend has significance to achieve human-level computation capability from machines. This computational ability can be achieved by developing evolutionary algorithms or mapping those evolutionary algorithms onto new generation computing systems: Quantum or Neuromorphic hardware. In this paper, we implemented the NP-hard optimization problem called Quadratic Unconstrained Binary Optimization (QUBO) problem for the solution of graph problems on the IBM's Neurosynaptic TrueNorth System. We have experimented on different types of graph problems with different levels of complexities and achieved encouraging results on IBM's Neuromorphic TrueNorth chip. Moreover, there are a set of potential applications have been discussed based on this proposed QUBO solution. Along with the QUBO on quantum annealing, it is the important first step towards the solutions of QUBO on Neuromorphic computing systems.

Abstract not provided