2,442 research outputs found
A Lite Fireworks Algorithm with Fractal Dimension Constraint for Feature Selection
As the use of robotics becomes more widespread, the huge amount of vision
data leads to a dramatic increase in data dimensionality. Although deep
learning methods can effectively process these high-dimensional vision data.
Due to the limitation of computational resources, some special scenarios still
rely on traditional machine learning methods. However, these high-dimensional
visual data lead to great challenges for traditional machine learning methods.
Therefore, we propose a Lite Fireworks Algorithm with Fractal Dimension
constraint for feature selection (LFWA+FD) and use it to solve the feature
selection problem driven by robot vision. The "LFWA+FD" focuses on searching
the ideal feature subset by simplifying the fireworks algorithm and
constraining the dimensionality of selected features by fractal dimensionality,
which in turn reduces the approximate features and reduces the noise in the
original data to improve the accuracy of the model. The comparative
experimental results of two publicly available datasets from UCI show that the
proposed method can effectively select a subset of features useful for model
inference and remove a large amount of noise noise present in the original data
to improve the performance.Comment: International Conference on Pharmaceutical Sciences 202
Multi-Objective Genetic Algorithm for Multi-View Feature Selection
Multi-view datasets offer diverse forms of data that can enhance prediction
models by providing complementary information. However, the use of multi-view
data leads to an increase in high-dimensional data, which poses significant
challenges for the prediction models that can lead to poor generalization.
Therefore, relevant feature selection from multi-view datasets is important as
it not only addresses the poor generalization but also enhances the
interpretability of the models. Despite the success of traditional feature
selection methods, they have limitations in leveraging intrinsic information
across modalities, lacking generalizability, and being tailored to specific
classification tasks. We propose a novel genetic algorithm strategy to overcome
these limitations of traditional feature selection methods for multi-view data.
Our proposed approach, called the multi-view multi-objective feature selection
genetic algorithm (MMFS-GA), simultaneously selects the optimal subset of
features within a view and between views under a unified framework. The MMFS-GA
framework demonstrates superior performance and interpretability for feature
selection on multi-view datasets in both binary and multiclass classification
tasks. The results of our evaluations on three benchmark datasets, including
synthetic and real data, show improvement over the best baseline methods. This
work provides a promising solution for multi-view feature selection and opens
up new possibilities for further research in multi-view datasets
Video Deepfake Classification Using Particle Swarm Optimization-based Evolving Ensemble Models
The recent breakthrough of deep learning based generative models has led to the escalated generation of photo-realistic synthetic videos with significant visual quality. Automated reliable detection of such forged videos requires the extraction of fine-grained discriminative spatial-temporal cues. To tackle such challenges, we propose weighted and evolving ensemble models comprising 3D Convolutional Neural Networks (CNNs) and CNN-Recurrent Neural Networks (RNNs) with Particle Swarm Optimization (PSO) based network topology and hyper-parameter optimization for video authenticity classification. A new PSO algorithm is proposed, which embeds Muller’s method and fixed-point iteration based leader enhancement, reinforcement learning-based optimal search action selection, a petal spiral simulated search mechanism, and cross-breed elite signal generation based on adaptive geometric surfaces. The PSO variant optimizes the RNN topologies in CNN-RNN, as well as key learning configurations of 3D CNNs, with the attempt to extract effective discriminative spatial-temporal cues. Both weighted and evolving ensemble strategies are used for ensemble formulation with aforementioned optimized networks as base classifiers. In particular, the proposed PSO algorithm is used to identify optimal subsets of optimized base networks for dynamic ensemble generation to balance between ensemble complexity and performance. Evaluated using several well-known synthetic video datasets, our approach outperforms existing studies and various ensemble models devised by other search methods with statistical significance for video authenticity classification. The proposed PSO model also illustrates statistical superiority over a number of search methods for solving optimization problems pertaining to a variety of artificial landscapes with diverse geometrical layouts
Intelligent Processing in Wireless Communications Using Particle Swarm Based Methods
There are a lot of optimization needs in the research and design of wireless communica- tion systems. Many of these optimization problems are Nondeterministic Polynomial (NP) hard problems and could not be solved well. Many of other non-NP-hard optimization problems are combinatorial and do not have satisfying solutions either. This dissertation presents a series of Particle Swarm Optimization (PSO) based search and optimization algorithms that solve open research and design problems in wireless communications. These problems are either avoided or solved approximately before.
PSO is a bottom-up approach for optimization problems. It imposes no conditions on the underlying problem. Its simple formulation makes it easy to implement, apply, extend and hybridize. The algorithm uses simple operators like adders, and multipliers to travel through the search space and the process requires just five simple steps. PSO is also easy to control because it has limited number of parameters and is less sensitive to parameters than other swarm intelligence algorithms. It is not dependent on initial points and converges very fast.
Four types of PSO based approaches are proposed targeting four different kinds of problems in wireless communications. First, we use binary PSO and continuous PSO together to find optimal compositions of Gaussian derivative pulses to form several UWB pulses that not only comply with the FCC spectrum mask, but also best exploit the avail- able spectrum and power. Second, three different PSO based algorithms are developed to solve the NLOS/LOS channel differentiation, NLOS range error mitigation and multilateration problems respectively. Third, a PSO based search method is proposed to find optimal orthogonal code sets to reduce the inter carrier interference effects in an frequency redundant OFDM system. Fourth, a PSO based phase optimization technique is proposed in reducing the PAPR of an frequency redundant OFDM system. The PSO based approaches are compared with other canonical solutions for these communication problems and showed superior performance in many aspects. which are confirmed by analysis and simulation results provided respectively. Open questions and future
Open questions and future works for the dissertation are proposed to serve as a guide for the future research efforts
Solving the G-problems in less than 500 iterations: Improved efficient constrained optimization by surrogate modeling and adaptive parameter control
Constrained optimization of high-dimensional numerical problems plays an
important role in many scientific and industrial applications. Function
evaluations in many industrial applications are severely limited and no
analytical information about objective function and constraint functions is
available. For such expensive black-box optimization tasks, the constraint
optimization algorithm COBRA was proposed, making use of RBF surrogate modeling
for both the objective and the constraint functions. COBRA has shown remarkable
success in solving reliably complex benchmark problems in less than 500
function evaluations. Unfortunately, COBRA requires careful adjustment of
parameters in order to do so.
In this work we present a new self-adjusting algorithm SACOBRA, which is
based on COBRA and capable to achieve high-quality results with very few
function evaluations and no parameter tuning. It is shown with the help of
performance profiles on a set of benchmark problems (G-problems, MOPTA08) that
SACOBRA consistently outperforms any COBRA algorithm with fixed parameter
setting. We analyze the importance of the several new elements in SACOBRA and
find that each element of SACOBRA plays a role to boost up the overall
optimization performance. We discuss the reasons behind and get in this way a
better understanding of high-quality RBF surrogate modeling
Evolutionary Algorithms
Evolutionary algorithms (EAs) are population-based metaheuristics, originally
inspired by aspects of natural evolution. Modern varieties incorporate a broad
mixture of search mechanisms, and tend to blend inspiration from nature with
pragmatic engineering concerns; however, all EAs essentially operate by
maintaining a population of potential solutions and in some way artificially
'evolving' that population over time. Particularly well-known categories of EAs
include genetic algorithms (GAs), Genetic Programming (GP), and Evolution
Strategies (ES). EAs have proven very successful in practical applications,
particularly those requiring solutions to combinatorial problems. EAs are
highly flexible and can be configured to address any optimization task, without
the requirements for reformulation and/or simplification that would be needed
for other techniques. However, this flexibility goes hand in hand with a cost:
the tailoring of an EA's configuration and parameters, so as to provide robust
performance for a given class of tasks, is often a complex and time-consuming
process. This tailoring process is one of the many ongoing research areas
associated with EAs.Comment: To appear in R. Marti, P. Pardalos, and M. Resende, eds., Handbook of
Heuristics, Springe
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