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Brain-inspired Hyperdimensional (HD) computing models cognition by exploiting properties of high dimensional statistics– high-dimensional vectors, instead of working with numeric values used in contemporary processors. A fundamental weakness of existing HD computing algorithms is that they require to use floating point models in order to provide acceptable accuracy on realistic classification problems. However, working with floating point values significantly increases the HD computation cost. To address this issue, we proposed QuantHD, a novel framework for quantization of HD computing model during training. QuantHD enables HD computing to work with a low-cost quantized model (binary or ternary model) while providing a similar accuracy as the floating point model. We accordingly propose an FPGA implementation which accelerates HD computing in both training and inference phases. We evaluate QuantHD accuracy and efficiency on various real-world applications, and observe that QuantHD can achieve on average 17.2% accuracy improvement as compared to the existing binarized HD computing algorithms which provide a similar computation cost. In terms of efficiency, QuantHD FPGA implementation can achieve on average 42.3× and 4.7× (34.1× and 4.1×) energy efficiency improvement and speedup during inference (training) as compared to the state-of-the-art HD computing algorithms.
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DeepER-HD: An Error Resilient HyperDimensional Computing Framework with DNN Front-End for Feature Selection
Brain-inspired hyperdimensional (HD) computing models mimic cognition through combinatorial bindings of biological neuronal data represented by high-dimensional vectors and related operations. However, the efficacy of HD computing depends strongly on input signal and data features used to realize such bindings. In this paper, we propose a new HD-computing framework based on a co-trainable DNN-based feature extractor pre-processor and a hyperdimensional computing system. When trained with restrictions on the ranges of hypervector elements for resilience to memory access errors, the framework achieves up to 135% accuracy improvement over baseline HD-computing for error-free operation and up to three orders of magnitude improvement in error resilience compared to the state-of-the-art. Results for a range of applications from image classification, face recognition, human activity recognition and medical diagnosis are presented and demonstrate the viability of the proposed ideas.
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- Award ID(s):
- 2128419
- PAR ID:
- 10541882
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-6555-9
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Location:
- Maceio, Brazil
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/LATS62223.2024.10534617
