journal = "IEEE Transactions on Sustainable Computing",
title = "Clustering and Symbolic Regression for Power
Consumption Estimation on Smartphone Hardware
Subsystems",
year = "2018",
volume = "3",
number = "4",
pages = "306--317",
abstract = "The subsystem in a smart phone means its hardware
components, such as the CPU, GPU, and screen.
Accurately estimating subsystem power consumption of
commercial smartphones is necessary for applicable to
wide research areas. Current subsystem power estimation
techniques are mostly based on power models, resulting
in considerable errors for various types of power
consumption behaviours. These include (1) asynchrony
between the measured power consumption and the
corresponding workload statistics, and (2) nonlinearity
concerning CPU idle states, pixels colours of AMOLED
screen, and GPU workload statistics. In this study, we
propose a novel usage-based, subsystem power estimation
method for a smartphone, namely Clustering and Symbolic
Regression (CSR) that takes these power consumption
behaviours into account so as to increase power
estimation accuracy. To address asynchrony, we cluster
the subsystem workload statistics into synchronous and
asynchronous groups by employing affinity propagation
clustering. To address nonlinearity, we employ symbolic
regression for fitting measured power consumptions with
respect to subsystem workload statistics. We compare
our approach with various power estimation methods,
Linear Regression Model (LM), Genetic Programming (GP),
and Support Vector Regression (SVR). The results show
Mean Absolute Percentage Error (MAPE) reduction between
23.61 and 42.55 percent on the estimated power
consumption of a simple (Nexus S) and complex (Galaxy
S4) smartphone subsystems.",