7,633 research outputs found
Scalable Solutions for Automated Single Pulse Identification and Classification in Radio Astronomy
Data collection for scientific applications is increasing exponentially and
is forecasted to soon reach peta- and exabyte scales. Applications which
process and analyze scientific data must be scalable and focus on execution
performance to keep pace. In the field of radio astronomy, in addition to
increasingly large datasets, tasks such as the identification of transient
radio signals from extrasolar sources are computationally expensive. We present
a scalable approach to radio pulsar detection written in Scala that
parallelizes candidate identification to take advantage of in-memory task
processing using Apache Spark on a YARN distributed system. Furthermore, we
introduce a novel automated multiclass supervised machine learning technique
that we combine with feature selection to reduce the time required for
candidate classification. Experimental testing on a Beowulf cluster with 15
data nodes shows that the parallel implementation of the identification
algorithm offers a speedup of up to 5X that of a similar multithreaded
implementation. Further, we show that the combination of automated multiclass
classification and feature selection speeds up the execution performance of the
RandomForest machine learning algorithm by an average of 54% with less than a
2% average reduction in the algorithm's ability to correctly classify pulsars.
The generalizability of these results is demonstrated by using two real-world
radio astronomy data sets.Comment: In Proceedings of the 47th International Conference on Parallel
Processing (ICPP 2018). ACM, New York, NY, USA, Article 11, 11 page
Gravitational Search For Designing A Fuzzy Rule-Based Classifiers For Handwritten Signature Verification
Handwritten signatures are used in authentication systems as a universal biometric identifier. Signature authenticity verification requires building and training a classifier. This paper describes a new approach to the verification of handwritten signatures by dynamic characteristics with a fuzzy rule-based classifier. It is suggested to use the metaheuristic Gravitational Search Algorithm for the selection of the relevant features and tuning fuzzy rule parameters. The efficiency of the approach was tested with an original dataset; the type II errors in finding the signature authenticity did not exceed 0.5% for the worst model and 0.08% for the best model
Binary Multi-Verse Optimization (BMVO) Approaches for Feature Selection
Multi-Verse Optimization (MVO) is one of the newest meta-heuristic optimization algorithms which imitates the theory of Multi-Verse in Physics and resembles the interaction among the various universes. In problem domains like feature selection, the solutions are often constrained to the binary values viz. 0 and 1. With regard to this, in this paper, binary versions of MVO algorithm have been proposed with two prime aims: firstly, to remove redundant and irrelevant features from the dataset and secondly, to achieve better classification accuracy. The proposed binary versions use the concept of transformation functions for the mapping of a continuous version of the MVO algorithm to its binary versions. For carrying out the experiments, 21 diverse datasets have been used to compare the Binary MVO (BMVO) with some binary versions of existing metaheuristic algorithms. It has been observed that the proposed BMVO approaches have outperformed in terms of a number of features selected and the accuracy of the classification process
Evolutionary algorithm-based analysis of gravitational microlensing lightcurves
A new algorithm developed to perform autonomous fitting of gravitational
microlensing lightcurves is presented. The new algorithm is conceptually
simple, versatile and robust, and parallelises trivially; it combines features
of extant evolutionary algorithms with some novel ones, and fares well on the
problem of fitting binary-lens microlensing lightcurves, as well as on a number
of other difficult optimisation problems. Success rates in excess of 90% are
achieved when fitting synthetic though noisy binary-lens lightcurves, allowing
no more than 20 minutes per fit on a desktop computer; this success rate is
shown to compare very favourably with that of both a conventional (iterated
simplex) algorithm, and a more state-of-the-art, artificial neural
network-based approach. As such, this work provides proof of concept for the
use of an evolutionary algorithm as the basis for real-time, autonomous
modelling of microlensing events. Further work is required to investigate how
the algorithm will fare when faced with more complex and realistic microlensing
modelling problems; it is, however, argued here that the use of parallel
computing platforms, such as inexpensive graphics processing units, should
allow fitting times to be constrained to under an hour, even when dealing with
complicated microlensing models. In any event, it is hoped that this work might
stimulate some interest in evolutionary algorithms, and that the algorithm
described here might prove useful for solving microlensing and/or more general
model-fitting problems.Comment: 14 pages, 3 figures; accepted for publication in MNRA
An Efficient High-Dimensional Gene Selection Approach based on Binary Horse Herd Optimization Algorithm for Biological Data Classification
The Horse Herd Optimization Algorithm (HOA) is a new meta-heuristic algorithm
based on the behaviors of horses at different ages. The HOA was introduced
recently to solve complex and high-dimensional problems. This paper proposes a
binary version of the Horse Herd Optimization Algorithm (BHOA) in order to
solve discrete problems and select prominent feature subsets. Moreover, this
study provides a novel hybrid feature selection framework based on the BHOA and
a minimum Redundancy Maximum Relevance (MRMR) filter method. This hybrid
feature selection, which is more computationally efficient, produces a
beneficial subset of relevant and informative features. Since feature selection
is a binary problem, we have applied a new Transfer Function (TF), called
X-shape TF, which transforms continuous problems into binary search spaces.
Furthermore, the Support Vector Machine (SVM) is utilized to examine the
efficiency of the proposed method on ten microarray datasets, namely Lymphoma,
Prostate, Brain-1, DLBCL, SRBCT, Leukemia, Ovarian, Colon, Lung, and MLL. In
comparison to other state-of-the-art, such as the Gray Wolf (GW), Particle
Swarm Optimization (PSO), and Genetic Algorithm (GA), the proposed hybrid
method (MRMR-BHOA) demonstrates superior performance in terms of accuracy and
minimum selected features. Also, experimental results prove that the X-Shaped
BHOA approach outperforms others methods
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