Search

The diversity of brain functions depend on the release of neurotransmitters in chemical synapses. The back gated three terminal field effect transistors (FETs) are auspicious candidates for the emulation of biological functions to recognize the proficient neuromorphic computing systems. In order to encourage the hysteresis loops, we treated the bottom side of MoTe2 flake with deep ultraviolet light in ambient conditions. Here, we modulate the short-term and long-term memory effects due to the trapping and de-trapping of electron events in few layers of a MoTe2 transistor. However, MoTe2 FETs are investigated to reveal the time constants of electron trapping/de-trapping while applying the gate-voltage pulses. Our devices exploit the hysteresis effect in the transfer curves of MoTe2 FETs to explore the excitatory/inhibitory post-synaptic currents (EPSC/IPSC), long-term potentiation (LTP), long-term depression (LTD), spike timing/amplitude-dependent plasticity (STDP/SADP), and paired pulse facilitation (PPF). Further, the time constants for potentiation and depression is found to be 0.6 and 0.9 s, respectively which seems plausible for biological synapses. In addition, the change of synaptic weight in MoTe2 conductance is found to be 41% at negative gate pulse and 38% for positive gate pulse, respectively. Our findings can provide an essential role in the advancement of smart neuromorphic electronics.

With growing technologies commercial sites, social media, organizations generate lots of data. However, this huge amount of information needs to be organized properly. For this, the text mining process used as extracting relevant features and knowledge of the given unstructured text documents. The document clustering method in text mining is used for retrieving interesting features. In which similar documents organize into different groups called clusters. The large dimensions of data become a barrier in the extraction of useful information, so using dimensionality reduction (DR) technique for reducing the dimensions of the data matrices. Further data divide into groups using the k-means clustering algorithm. This study implements TF-IDF, singular value decomposition (SVD), non-negative matrix factorization (NMF), and k-means clustering. Finally, the results of the comparison of scores of kmeans, SVD with kmeans, and NMF with k-means are shown by graphical representation. The system uses 20 newsgroup datasets for simulating results.

Controlled resistive switching behavior has shown potential for brain-inspired functionalities and feasibility for multi-functional photelectric sensors. For the first time, bias-polarity dependent switching characteristic is observed in forming-free W/Nb2O5/(Pt, ITO) sandwiched structures. When voltage bias was applied to the W electrode, a multi-level cell (MLC) with more than two switching states was observed while a single-level (SLC) with binary switching states was observed with Pt or ITO biasing electrode. Moreover, devices with Pt electrodes exhibit higher SET voltages (>1) while devices with ITO electrodes exhibit lower SET voltages (