2,895 research outputs found
In-Network Distributed Solar Current Prediction
Long-term sensor network deployments demand careful power management. While
managing power requires understanding the amount of energy harvestable from the
local environment, current solar prediction methods rely only on recent local
history, which makes them susceptible to high variability. In this paper, we
present a model and algorithms for distributed solar current prediction, based
on multiple linear regression to predict future solar current based on local,
in-situ climatic and solar measurements. These algorithms leverage spatial
information from neighbors and adapt to the changing local conditions not
captured by global climatic information. We implement these algorithms on our
Fleck platform and run a 7-week-long experiment validating our work. In
analyzing our results from this experiment, we determined that computing our
model requires an increased energy expenditure of 4.5mJ over simpler models (on
the order of 10^{-7}% of the harvested energy) to gain a prediction improvement
of 39.7%.Comment: 28 pages, accepted at TOSN and awaiting publicatio
PUGeo-Net: A Geometry-centric Network for 3D Point Cloud Upsampling
This paper addresses the problem of generating uniform dense point clouds to
describe the underlying geometric structures from given sparse point clouds.
Due to the irregular and unordered nature, point cloud densification as a
generative task is challenging. To tackle the challenge, we propose a novel
deep neural network based method, called PUGeo-Net, that learns a
linear transformation matrix for each input point. Matrix
approximates the augmented Jacobian matrix of a local parameterization and
builds a one-to-one correspondence between the 2D parametric domain and the 3D
tangent plane so that we can lift the adaptively distributed 2D samples (which
are also learned from data) to 3D space. After that, we project the samples to
the curved surface by computing a displacement along the normal of the tangent
plane. PUGeo-Net is fundamentally different from the existing deep learning
methods that are largely motivated by the image super-resolution techniques and
generate new points in the abstract feature space. Thanks to its
geometry-centric nature, PUGeo-Net works well for both CAD models with sharp
features and scanned models with rich geometric details. Moreover, PUGeo-Net
can compute the normal for the original and generated points, which is highly
desired by the surface reconstruction algorithms. Computational results show
that PUGeo-Net, the first neural network that can jointly generate vertex
coordinates and normals, consistently outperforms the state-of-the-art in terms
of accuracy and efficiency for upsampling factor .Comment: 17 pages, 10 figure
An evaluation of galaxy and ruffus-scripting workflows system for DNA-seq analysis
>Magister Scientiae - MScFunctional genomics determines the biological functions of genes on a global scale by
using large volumes of data obtained through techniques including next-generation
sequencing (NGS). The application of NGS in biomedical research is gaining in
momentum, and with its adoption becoming more widespread, there is an increasing
need for access to customizable computational workflows that can simplify, and offer
access to, computer intensive analyses of genomic data. In this study, the Galaxy and
Ruffus frameworks were designed and implemented with a view to address the
challenges faced in biomedical research. Galaxy, a graphical web-based framework,
allows researchers to build a graphical NGS data analysis pipeline for accessible,
reproducible, and collaborative data-sharing. Ruffus, a UNIX command-line framework
used by bioinformaticians as Python library to write scripts in object-oriented style,
allows for building a workflow in terms of task dependencies and execution logic. In
this study, a dual data analysis technique was explored which focuses on a comparative
evaluation of Galaxy and Ruffus frameworks that are used in composing analysis
pipelines. To this end, we developed an analysis pipeline in Galaxy, and Ruffus, for the
analysis of Mycobacterium tuberculosis sequence data. Furthermore, this study aimed
to compare the Galaxy framework to Ruffus with preliminary analysis revealing that the
analysis pipeline in Galaxy displayed a higher percentage of load and store instructions.
In comparison, pipelines in Ruffus tended to be CPU bound and memory intensive. The
CPU usage, memory utilization, and runtime execution are graphically represented in
this study. Our evaluation suggests that workflow frameworks have distinctly different
features from ease of use, flexibility, and portability, to architectural designs
NUMERICAL UPDATING ON COLLAPSE SIMULATION OF MULTI-STORY BUILDINGS THROUGH HYBRID TESTING
The present dissertation introduces an innovative numerical updating approach within fully simulated hybrid testing with substructuring techniques through collapse. The proposed approach is based on utilizing the measured response from the experimental substructure to update during the test the parameters of the components of the numerical substructure. The main research objective is to improve the ability to predict and simulate collapse through hybrid testing with substructuring techniques. The proposed numerical updating approach demonstrates to be capable of reliably reduce the epistemic uncertainty existent on the calibration of initial component parameters of the numerical substructure, especially when the system is near the limit state of collapse
SIRU development. Volume 1: System development
A complete description of the development and initial evaluation of the Strapdown Inertial Reference Unit (SIRU) system is reported. System development documents the system mechanization with the analytic formulation for fault detection and isolation processing structure; the hardware redundancy design and the individual modularity features; the computational structure and facilities; and the initial subsystem evaluation results
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