3 results on '"Pichel, Juan C."'
Search Results
2. A multistage retrieval system for health-related misinformation detection.
- Author
-
Fernández-Pichel, Marcos, Losada, David E., and Pichel, Juan C.
- Subjects
- *
DEEP learning , *NATURAL language processing , *SUPERVISED learning , *ARTIFICIAL intelligence , *MISINFORMATION , *ACCESS to information - Abstract
Web search is widely used to find online medical advice. As such, health-related information access requires retrieval algorithms capable of promoting reliable documents and filtering out unreliable ones. To this end, different types of components, such as query-document matching features, passage relevance estimation and AI-based reliability estimators, need to be combined. In this paper, we propose an entire pipeline for misinformation detection, based on the fusion of multiple content-based features. We present experiments which study the influence of each pipeline stage for the target task. Our technological solution incorporates signals from technologies derived from diverse research fields, including search, deep learning for natural language processing, as well as advanced supervised and unsupervised learning. To combine evidence, different score fusion strategies are compared, including unsupervised rank fusion techniques and learning-to-rank methods. The reference framework for empirically validating our solution is the TREC Health Misinformation Track, which provides several challenging subtasks that foster research on the identification of reliable and correct information for health-related decision making tasks. More specifically, we address a total recall task, the goal of which is to identify all the documents conveying incorrect information for a specific set of topics, and an ad-hoc retrieval task, aiming to rank credible and correct information over incorrect information. All variants are evaluated with an assorted set of effectiveness metrics, which includes standard search measures, such as R-Precision, Average Precision or Normalised Discounted Cumulative Gain, and innovative metrics based on the compatibility between the ranked output and two reference rankings composed of helpful and harmful documents, respectively. Our experiments demonstrate the effectiveness of the proposed pipeline stages and indicate that sophisticated supervised fusion methods do not fare better than simpler fusion alternatives. Additionally, for reliability estimation, unsupervised textual similarity performs better than textual classification based on supervised learning. The results also show that the presented approach is highly competitive when compared with state-of-the-art solutions for the same problem. • A complete system for health misinformation detection is proposed. • Several content-based features are proposed for identifying health misinformation. • The performance of the different features and against external baselines is reported. • New metrics considering harmfulness and helpfulness of retrieved documents are used. • The technology developed is freely available for other researchers or stakeholders. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
3. An accurate machine learning model to study the impact of realistic metal grain granularity on Nanosheet FETs.
- Author
-
Fernandez, Julian G., Seoane, Natalia, Comesaña, Enrique, Pichel, Juan C., and Garcia-Loureiro, Antonio
- Subjects
- *
PRINCIPAL components analysis , *SEMICONDUCTOR devices , *THRESHOLD voltage , *MACHINE learning , *METALS , *MULTILAYER perceptrons - Abstract
In this work, we present a machine learning neural network model to predict the impact of realistic metal grain granularity (MGG) variability on the threshold voltage V T h and on the I D − V G characteristics of a silicon-based 12 nm gate length nanosheet FET. This model is based on the multi-layer perceptron (MLP) machine learning architecture. As realistic MGG maps consist of the distribution of grains on the gate with different work-function values, it is relevant to apply algorithms such as the principal component analysis to reduce these features to the most representative ones. Once the realistic MGG features are correctly reduced without losing information, we train two different neural networks with the neurons in the output layer as the only difference, to predict the V T h and the I D − V G characteristics, respectively. The comparison between TCAD results and the model, shows excellent agreement for the mean and standard deviation of V T h distributions for different average grain sizes values (from 3 nm to 10 nm) demonstrating the accuracy of the machine learning model. Also, we study the amount of data needed to accurately train the MLPs, leading to results that allow us to drastically reduce the computational time required to perform variability studies for state-of-art nano FET devices. • Machine learning model to predict the impact of variability on state-of-the-art semiconductor devices. • Prediction of the impact of metal grain granularity on the Vth and on the I-V characteristics of a 12 nm gate length Si-based nanosheet FET. • Model that reduces the computational cost of variability statistical studies. • Comparison of the model performance against TCAD simulations. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.