67 research outputs found
Online Human Activity Recognition using Low-Power Wearable Devices
Human activity recognition~(HAR) has attracted significant research interest
due to its applications in health monitoring and patient rehabilitation. Recent
research on HAR focuses on using smartphones due to their widespread use.
However, this leads to inconvenient use, limited choice of sensors and
inefficient use of resources, since smartphones are not designed for HAR. This
paper presents the first HAR framework that can perform both online training
and inference. The proposed framework starts with a novel technique that
generates features using the fast Fourier and discrete wavelet transforms of a
textile-based stretch sensor and accelerometer. Using these features, we design
an artificial neural network classifier which is trained online using the
policy gradient algorithm. Experiments on a low power IoT device (TI-CC2650
MCU) with nine users show 97.7% accuracy in identifying six activities and
their transitions with less than 12.5 mW power consumption.Comment: This is in proceedings of ICCAD 2018. The datasets are available at
https://github.com/gmbhat/human-activity-recognitio
Scale-free memory model for multiagent reinforcement learning. Mean field approximation and rock-paper-scissors dynamics
A continuous time model for multiagent systems governed by reinforcement
learning with scale-free memory is developed. The agents are assumed to act
independently of one another in optimizing their choice of possible actions via
trial-and-error search. To gain awareness about the action value the agents
accumulate in their memory the rewards obtained from taking a specific action
at each moment of time. The contribution of the rewards in the past to the
agent current perception of action value is described by an integral operator
with a power-law kernel. Finally a fractional differential equation governing
the system dynamics is obtained. The agents are considered to interact with one
another implicitly via the reward of one agent depending on the choice of the
other agents. The pairwise interaction model is adopted to describe this
effect. As a specific example of systems with non-transitive interactions, a
two agent and three agent systems of the rock-paper-scissors type are analyzed
in detail, including the stability analysis and numerical simulation.
Scale-free memory is demonstrated to cause complex dynamics of the systems at
hand. In particular, it is shown that there can be simultaneously two modes of
the system instability undergoing subcritical and supercritical bifurcation,
with the latter one exhibiting anomalous oscillations with the amplitude and
period growing with time. Besides, the instability onset via this supercritical
mode may be regarded as "altruism self-organization". For the three agent
system the instability dynamics is found to be rather irregular and can be
composed of alternate fragments of oscillations different in their properties.Comment: 17 pages, 7 figur
Ecosystem-based management for military training, biodiversity, carbon storage and climate resiliency on a complex coastal land/water-scape
The Defense Coastal/Estuarine Research Program (DCERP) was a 10-year multi-investigator project funded by the Department of Defense to improve understanding of ecosystem processes and their interactions with natural and anthropogenic stressors at the Marine Corps Base Camp Lejeune (MCBCL) located in coastal North Carolina. The project was aimed at facilitating ecosystem-based management (EBM) at the MCBCL and other coastal military installations. Because of its scope, interdisciplinary character, and duration, DCERP embodied many of the opportunities and challenges associated with EBM, including the need for explicit goals, system models, long-term perspectives, systems complexity, change inevitability, consideration of humans as ecosystem components, and program adaptability and accountability. We describe key elements of this program, its contributions to coastal EBM, and its relevance as an exemplar of EBM
Patient education for adults with rheumatoid arthritis (Review)
Patient education shows short-term benefits for adults with rheumatoid arthritis. The purpose was to examine the effectiveness of patient education interventions on health status (pain, functional disability, psychological well-being and disease activity) in patients with rheumatoid arthritis (RA). Patient education had a small beneficial effect at first follow-up for disability, joint counts, patient global assessment, psychological status, and depression. At final follow-up (3-14 months) no evidence of significant benefits was found
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