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Ali Katanforoush

Publications and source records attributed to Ali Katanforoush.

4 recordsLinked to original sources

A Semi-supervised Fake News Detection using Sentiment Encoding and LSTM with Self-Attention

Micro-blogs and cyber-space social networks are the main communication mediums to receive and share news nowadays. As a side effect, however, the networks can disseminate fake news that harms individuals and the society. Several methods have been developed to detect fake news, but the majority require large sets of manually labeled data to attain the application-level accuracy. Due to the strict privacy policies, the required data are often inaccessible or limited to some specific topics. On the other side, quite diverse and abundant unlabeled data on social media suggests that with a few labeled data, the problem of detecting fake news could be tackled via semi-supervised learning. Here, we propose a semi-supervised self-learning method in which a sentiment analysis is acquired by some state-of-the-art pretrained models. Our learning model is trained in a semi-supervised fashion and incorporates LSTM with self-attention layers. We benchmark our model on a dataset with 20,000 news content along with their feedback, which shows better performance in precision, recall, and measures compared to competitive methods in fake news detection.

cs.AI

Global and Local Visual Processing: Influence of Perceptual Field Variables

The Global Precedence Effect (GPE) suggests that the processing of global properties of a visual stimulus precedes the processing of local properties. The generality of this theory was argued for four decades during different known Perceptual Field Variables. The effect size of various PFVs, regarding the findings during these four decades, were pooled in our recent meta-analysis study. Pursuing the study, in the present paper, we explore the effects of Congruency, Size, and Sparsity and their interaction on global advantage in two different experiments with different task paradigms; Matching judgment and Similarity judgment. Upon results of these experiments, Congruency and Size have significant effects and Sparsity has small effects. Also, the task paradigm and its interaction with other PFVs are shown significant effects in this study, which shows the prominence of the role of task paradigms in evaluating PFVs' effects on GPE. Also, we found that the effects of these parameters were not specific to the special condition that individuals were instructed to retinal stabilize. So, the experiments were more extendible to daily human behavior.

cs.CV

Detailed instantaneous ionization rate of H$_2^+$ in intense laser field

Component instantaneous ionization rate (IIR) is introduced and the approach of its calculation is formulated. The component IIR's and the overall (time-averaged) component ionization rates are calculated for H$_2^+$ at different values of inter-nuclear distance in a linearly polarized laser field with $1.0 \times10^{14}$W cm$^{-2}$ intensity and $λ\sim 1064 $nm wavelength by direct numerical solution of the fixed-nuclei full dimensional time-dependent Schr ödinger equation. The exact overall component ionization rates calculated by time-averaging of the component IIR are compared with those calculated approximately via the virtual detector method (VD). Details of the time dependent behavior of the outgoing and incoming electron wavepackets of the H$_2^+$ system in intense laser field at sub-femtosecond time scale are studied based on the calculated component IIR. It is shown clearly that the positive (outgoing electron wavepacket) signals of the IIR and its z component are strong and sharp but the negative (returning electron wavepacket) signals of the IIR are smooth and weak. The structure of the $ρ$ component of the IIR has smooth structure. Relation between the R-dependent ionization rate and duration of the ramp of the laser pulse is studied and it is explicitly shown that for internuclear distance R<5.6, when the laser pulse is turned on without a ramp, the first peak of R-dependent ionization rates moves towards the peak of the lower time dependent Floquet quasi-energy state (QES).

physics.atom-ph

Instantaneous ionization rate of H$_2^+$ in intense laser field; Interpretation of the Enhanced Ionization

The fixed-nuclei full dimensional time-dependent Schr ödinger equation is directly solved for H$_2^+$ in the linearly polarized laser field of $I \sim 1.0 \times 10^{14}$W cm$^{-2}$ and $λ\sim 1064 $nm Instantaneous ionization rate has been introduced and calculated by evaluating the instantaneous imaginary energy of the system. It is shown that positive (negative) values of instantaneous imaginary energy of the system represent the incoming (outgoing) instantaneous current of electron. This approach allows us to determine not only the instantaneous intensity but also the instantaneous direction of the electronic current. The transient behavior of the electron wavepacket in intense laser field can thus be probed precisely. Details of the enhanced ionization rates are studied based on the instantaneous ionization rates. This approach gives direct evidence for existence of the effect of charge-resonance-enhanced multiphoton resonances of the quasi-energy states (QES) with excited electronic states at some particular internuclear distances. Finally, Contributions of the individual time dependent Floquet QES to the overall ionization rates are evaluated.

physics.atom-ph