Deep learning for COVID-19 topic modelling via Twitter: Alpha, Delta and Omicron

Topic modelling with innovative deep learning methods has gained interest for a wide range of applications that includes COVID-19. Topic modelling can provide, psychological, social and cultural insights for understanding human behaviour in extreme events such as the COVID-19 pandemic. In this paper, we use prominent deep learning-based language models for COVID-19 topic modelling taking into account data from emergence (Alpha) to the Omicron variant. We apply topic modeling to review the public behaviour across the first, second and third waves based on Twitter dataset from India. Our results show that the topics extracted for the subsequent waves had certain overlapping themes such as covers governance, vaccination, and pandemic management while novel issues aroused in political, social and economic situation during COVID-19 pandemic. We also found a strong correlation of the major topics qualitatively to news media prevalent at the respective time period. Hence, our framework has the potential to capture major issues arising during different phases of the COVID-19 pandemic which can be extended to other countries and regions.

Lande J; Pillay A; Chandra R

arxiv:2303.00135 (2023)

An evaluation of Google Translate for Sanskrit to English translation via sentiment and semantic analysis

Google Translate has been prominent for language translation; however, limited work has been done in evaluating the quality of translation when compared to human experts. Sanskrit one of the oldest written languages in the world. In 2022, the Sanskrit language was added to the Google Translate engine. Sanskrit is known as the mother of languages such as Hindi and an ancient source of the Indo-European group of languages. Sanskrit is the original language for sacred Hindu texts such as the Bhagavad Gita. In this study, we present a framework that evaluates the Google Translate for Sanskrit using the Bhagavad Gita. We first publish a translation of the Bhagavad Gita in Sanskrit using Google Translate. Our framework then compares Google Translate version of Bhagavad Gita with expert translations using sentiment and semantic analysis via BERT-based language models. Our results indicate that in terms of sentiment and semantic analysis, there is low level of similarity in selected verses of Google Translate when compared to expert translations. In the qualitative evaluation, we find that Google translate is unsuitable for translation of certain Sanskrit words and phrases due to its poetic nature, contextual significance, metaphor and imagery. The mistranslations are not surprising since the Bhagavad Gita is known as a difficult text not only to translate, but also to interpret since it relies on contextual, philosophical and historical information. Our framework lays the foundation for automatic evaluation of other languages by Google Translate

Shukla A; Bansal C; Badhe S; Ranjan M; Chandra R

arxiv:2303.07201 (2023)

Physics-informed neural entangled-ladder network for inhalation impedance of the respiratory system

The use of machine learning methods for modelling bio-systems is becoming prominent which can further improve bio-medical technologies. Physics-informed neural networks (PINNs) can embed the knowledge of physical laws that govern a system during the model training process. PINNs utilise differential equations in the model which traditionally used numerical methods that are computationally complex. We integrate PINNs with an entangled ladder network for modelling respiratory systems by considering a lungs conduction zone to evaluate the respiratory impedance for different initial conditions. We evaluate the respiratory impedance for the inhalation phase of breathing for a symmetric model of the human lungs using entanglement and continued fractions.

Kumar AK; Jain S; Jain S; Ritam M; Xia Y; Chandra R

Computer Methods and Programs in Biomedicine, vol. 231, pp. 107421 - 107421 (2023)

Covered in ‘t~ai Seminar Series’ by Dr Amit Kumar

Cyclone trajectory and intensity prediction with uncertainty quantification using variational recurrent neural networks

Cyclone track forecasting is a critical climate science problem involving time-series prediction of cyclone location and intensity. Machine learning methods have shown much promise in this domain, especially deep learning methods such as recurrent neural networks (RNNs) However, these methods generally make single-point predictions with little focus on uncertainty quantification. Although Markov Chain Monte Carlo (MCMC) methods have often been used for quantifying uncertainty in neural network predictions, these methods are computationally expensive. Variational Inference (VI) is an alternative to MCMC sampling that approximates the posterior distribution of parameters by minimizing a KL-divergence loss between the estimate and the true posterior. In this paper, we present variational RNNs for cyclone track and intensity prediction in four different regions across the globe. We utilise simple RNNs and long short-term memory (LSTM) RNNs and use the energy score (ES) to evaluate multivariate probabilistic predictions. The results show that variational RNNs provide a good approximation with uncertainty quantification when compared to conventional RNNs while maintaining prediction accuracy.

Kapoor A; Negi A; Marshall L; Chandra R

Environmental Modelling & Software, vol. 162, pp. 105654 - 105654 (2023)