4 research outputs found
Hierarchical Classification Using Evolutionary Strategy
Hierarchical classification is a problem with applications in many areas as protein function prediction where the dates are hierarchically structured. Therefore, it is necessary the development of algorithms able to induce hierarchical classification models. This paper presents experimenters using the algorithm for hierarchical classification called Hierarchical Classification using Evolutionary Strategy (HC-ES). It was tested in eight datasets the G-Protein-Coupled Receptor (GPCR) and Enzyme Commission Codes (EC). The results are compared with other hierarchical classifier using the distance and hF-Measure
Coherent Hierarchical Multi-Label Classification Networks
Hierarchical multi-label classification (HMC) is a challenging classification
task extending standard multi-label classification problems by imposing a
hierarchy constraint on the classes. In this paper, we propose C-HMCNN(h), a
novel approach for HMC problems, which, given a network h for the underlying
multi-label classification problem, exploits the hierarchy information in order
to produce predictions coherent with the constraint and improve performance. We
conduct an extensive experimental analysis showing the superior performance of
C-HMCNN(h) when compared to state-of-the-art models.Comment: Neural Information Processing Systems 202
Hierarchical ensemble methods for protein function prediction
Protein function prediction is a complex multiclass multilabel classification problem, characterized by multiple issues such as the incompleteness of the available annotations, the integration of multiple sources of high dimensional biomolecular data, the unbalance of several functional classes, and the difficulty of univocally determining negative examples. Moreover, the hierarchical relationships between functional classes that characterize both the Gene Ontology and FunCat taxonomies motivate the development of hierarchy-aware prediction methods that showed significantly better performances than hierarchical-unaware \u201cflat\u201d prediction methods. In this paper, we provide a comprehensive review of hierarchical methods for protein function prediction based on ensembles of learning machines. According to this general approach, a separate learning machine is trained to learn a specific functional term and then the resulting predictions are assembled in a \u201cconsensus\u201d ensemble decision, taking into account the hierarchical relationships between classes. The main hierarchical ensemble methods proposed in the literature are discussed in the context of existing computational methods for protein function prediction, highlighting their characteristics, advantages, and limitations. Open problems of this exciting research area of computational biology are finally considered, outlining novel perspectives for future research
Advancing the analysis of architectural fabric structures, neural networks and uncertainty
PhD ThesisIn current practice a plane stress framework comprising elastic moduli and Poisson’s
ratios is most commonly used to represent the mechanical properties of architectural
fabrics. This is often done to enable structural analysis utilising commercially available,
non-specialist, finite element packages. Plane stress material models endeavour to fit a flat
plane to the highly non-linear stress strain response surface of architectural fabric.
Neural networks have been identified as a possible alternative to plane stress material
models. Through a process of training they are capable of capturing the relationship
between experimental input and output data. With the addition of historical inputs and
internal variables it has been demonstrated that neural network models are capable of
representing complex history dependant behaviour. The resulting neural network
architectural fabric material models have been implemented within custom large strain
finite element code. The finite element code, capable of using either a neural network or
plane stress material model, utilises a dynamic relaxation solution algorithm and includes
geodesic string control for soap film form-finding. Analytical FORM reliability analysis
using implied stiffness matrices' derived from the equations of the neural network model
has also been investigated