Indian Institute of Technology Bhilai

Ahmad I., Gatla P., Mundotiya R.

Sarcasm identification in textual data is the most captivating area of research in the current research trends. It is a challenging task for humans as well as for the computer. In this article, we have tried to identify sarcasm in the Hindi newspaper headlines of two of the most-read Hindi newspapers in India, namely Hindustan and Dainik Jagran. Initially, we collected 88,518 Hindi newspaper headlines and identified 1,945 headlines to be sarcastic, which we have considered for the present study. The headlines taken into consideration belong to the political domain and were published during some of the recent Legislative Assembly Elections of 2020, 2021, and 2022. Various machine learning and deep learning techniques have been used to develop the baseline models. It justifies the assumption that sarcastic text does not always bear a negative sentiment. It may bear a positive sentiment depending on the context. The present article aims at the creation of a dataset consisting of 1,945 Hindi newspaper headlines, training and testing machine learning and deep learning models, namely Extra Trees Classifier, Random Forest Classifier, XGBClassifier, fasttext-stackedTCN, and mBERT-stackedTCN for sarcasm identification on the dataset and comparing the results obtained by the models after the experiment. Out of all the choosen models, the Random Forest Classifier performs better with \(F_1\) score of 92.11 before data augmentation and 90.68 after data augmentation.

Pandey A., Chauhan N.

Parveen S., Sharma K., Patra S., Mehta P.

Abstract While most of the results of the neutrino oscillation experiments can be accommodated within the standard paradigm of three active flavors, there are tantalizing hints of an eV-scale sterile neutrino from anomalous results of a few short baseline experiments. This additional light sterile neutrino is expected to leave an imprint on the physics observables pertaining to standard unknowns such as determination of the Dirac-type leptonic CP phase, $$\delta _{13},$$ δ 13 , the question of neutrino mass hierarchy and the octant of $$\theta _{23}.$$ θ 23 . The upcoming long baseline neutrino experiments such as T2HK, DUNE and P2O will be sensitive to active – sterile mixing. In the present work, we examine and assess the capability of these long baseline experiments to probe the sterile neutrino at the level of probabilities and event rates. We perform a detailed study by taking into account the values of parameters that are presently allowed and (a) study the impact on CP violation by examining the role played by various appearance and disappearance channels, (b) address the question of disentangling the intrinsic effects from extrinsic effects in the standard paradigm as well as three active plus one light sterile neutrino, and finally (c) assess the ability of these long baseline experiments to distinguish between the two scenarios. Our results indicate that for the true values of sterile parameters and for all values of $$\delta _{13},$$ δ 13 , the sensitivity of P2O is the lowest while the sensitivity of T2HK is modest $$(<3\,\sigma )$$ ( < 3 σ ) and the sensitivity of DUNE is $$> 3\,\sigma .$$ > 3 σ . For larger values of the sterile mixing angles, there is an improvement in the sensitivity for all the three considered experiments.

Sivarani T., Subramanian S., Bandyopadhyay A., Banerjee P., Bhattacharya S., Choudhury S., Ghosh S., Hema B.P., Jog C., Hota A., Joshi Y., Karinkuzhi D., Maitra C., Malhan K., Nayak P.K., et. al.

This article addresses key open questions in the Milky Way and neighboring galaxies, focusing on utilizing stars and stellar populations to trace galaxy formation and evolution processes. It offers an overview of the current landscape based on community-contributed white papers and outlines emerging research avenues alongside specific observational strategies relevant to the Indian context. Recent advancements in observations, such as precision astrometry from Gaia and asteroseismology enabled by Kepler, have reinvigorated interest in stellar physics, including its role in characterizing exoplanet atmospheres and understanding planet formation and evolution. Upcoming projects like the Rubin Observatory (LSST) and future large spectroscopic surveys will significantly enhance our ability to study stellar populations across various galaxies. These efforts will improve our understanding of dark matter distribution in galaxies, galaxy formation, and their evolution. Furthermore, by studying galaxies within the local volume, researchers can delve into the history of the formation of low-mass dwarf galaxies, the most common type of galaxy in the Universe. The local volume presents an excellent opportunity to test theories of hierarchical galaxy formation and assembly, especially since high-redshift observations of these galaxies’ formation epochs are beyond the reach of current telescopes. Therefore, this article seeks to summarize the current understanding and chart a path forward for the field.

Pradhan J., Nenavath H.

Pramanick A., Babori C., Albertini F., Gjørup F.H., Oudot A.B., Kumar A., Jørgensen M.R., Daniel L.

Recent advances in 3D printing have enabled fabrication of architected functional ceramics with tunable functionalities at reduced weight and cost. An essential cornerstone of materials design is to determine structure–property relations. For polycrystalline ferroelectrics, such relationships can be complex due to several microscopic mechanisms, such as lattice strains and/or domain switching, which show nonlinear dependence on external stimuli and are furthermore dependent on grain orientations. For architected materials, these microscopic mechanisms can also be spatially nonuniform. Herein, the development of appropriate methodology is entailed to correlate functional properties of architected ferroelectrics with spatial‐ and orientation‐resolved microscopic mechanisms. Herein, using in situ orientation‐resolved X‐ray microdiffraction, it is shown that nonlinear polarization and strain responses in a 3D‐printed architected ferroelectric are driven by localized progression of non‐180° domain switching, which depends not only on the internal distribution of electric‐field lines but also on the evolving long‐range stress fields resulting from inhomogeneous domain‐switching transformation strains. In this current study, it is indicated that nonlinear behavior in architected ferroelectrics can be effectively tuned by appropriate design of sample geometry, which controls the internal electric‐field distribution in the material.

Gaur D.R., Gorain B., Patra S., Singh R.R.

We study approximation algorithms for the forest cover and bounded forest cover problems. A probabilistic $$2+\epsilon $$ approximation algorithm for the forest cover problem is given using the method of dual fitting. A deterministic algorithm with a 2-approximation ratio that rounds the optimal solution to a linear program is given next. The 2-approximation for the forest cover is then used to give a 6-approximation for the bounded forest cover problem. The use of the probabilistic method to develop the $$2+\epsilon $$ approximation algorithm may be of independent interest.

Bhyravarapu S., Kumari S., Vinod Reddy I.

A proper vertex coloring of a connected graph G is called an odd coloring if, for every vertex v of G there is a color that appears odd number of times in the open neighborhood of v. The minimum number of colors required to obtain an odd coloring of G is called the odd chromatic number of G and it is denoted by $$\chi _{o}(G)$$ . The problem of determining $$\chi _o(G)$$ is $$\textsf{NP}$$ -hard. Given a graph G and an integer k, the Odd Coloring problem is to decide whether $$\chi _o(G)$$ is at most k. In this paper, we study the problem from the viewpoint of parameterized complexity. In particular, we study the problem with respect to structural graph parameters. We prove that the problem admits a polynomial kernel when parameterized by distance to clique. On the other hand, we show that the problem cannot have a polynomial kernel when parameterized by vertex cover number unless $$\textsf{NP} \subseteq \mathsf{Co {\text{- }} NP/poly}$$ . We show that the problem is fixed-parameter tractable when parameterized by distance to cluster, distance to co-cluster, or neighborhood diversity. We show that the problem is $$\mathsf{W[1]}$$ -hard parameterized by clique-width. Finally, we study the problem on restricted graph classes. We show that the problem can be solved in polynomial time on cographs and split graphs.

Pal S., Rakshit T., Saha S., Jinagal D.

Jain A., Sahu B., Ingale N., BANERJEE S.

A new path has been opened by the widespread use of ionic liquids (ILs) in reversible-deactivation radical polymerization (RDRP) procedures to address the problems caused by hazardous solvent. Additionally, a photoinduced RDRP (photoRDRP) of methacrylate monomer in recyclable IL has been developed, which is catalyzed by magnetic nano zero valent iron (nZVI), enabling incredible control over Mn and Đs during the polymerization of methacrylate by simply turning the UVA radiation (λmax = 352 nm) "ON" and "OFF". This allows for good temporal control. Furthermore, the chain end fidelity was determined through the synthesis of many distinct diblock copolymers with permissible Đs values (≤1.20).

Taramati, Sahu R., Patel U., Ghosh K., Patra S.

Abstract We are considering a minimal U(1) B extension of the Standard Model (SM) by promoting the baryon number as a local gauge symmetry to accommodate a stable dark matter (DM) candidate. The gauge theory of baryons induces non-trivial triangle gauge anomalies, and we provide a simple anomaly-free solution by adding three exotic fermions. A scalar S spontaneously breaks the U(1) B symmetry, leaving behind a discrete Z 2 symmetry that ensures the stability of the lightest exotic fermion originally introduced to cancel the triangle gauge anomalies. Scenarios with weakly interacting DM candidates having non-zero hypercharge usually face stringent constraints from experimental bounds on the DM spin-independent direct-detection (SIDD) cross-section. In this work, we consider a two-component singlet-doublet fermionic dark matter scenario, which significantly relaxes the constraints from bounds on the DM SIDD cross-section for suppressed single-doublet mixing. We show that the model offers a viable parameter space for a cosmologically consistent DM candidate that can be probed through direct detection searches, collider experiments, and gravitational wave (GW) experiments.

Mishra S., Kherani A.A.

Chowdhury M.M., Murari K., Hasan M.S., Kamalasadan S.

Dolui S., Sahu B., Banerjee S.

AbstractInspired by the extreme structural complexity and functional efficiency of biomolecules, researchers have developed stimuli‐responsive materials, capable of adapting their structural conformations and physicochemical properties upon external changes in temperature, pH, light, etc. These materials can expand, contract, or bend in response to external stimuli, which makes them useful for a variety of applications such as biomedicine, sensors, shape‐memory devices, and smart interface materials. Multistimuli‐responsive materials exhibit enhanced features than single‐/dual‐responsive materials, affording enhanced fine tuning of their parameters. Among such materials, reversibly cross‐linked networks have generated increasing interest recently due to their 3D architecture and unique properties, based on the low viscosity, good solubility, and high functionality of the building blocks, which can be further modified. In order to achieve dynamic self‐assembly, future research on stimuli‐responsive macromolecular self‐assembly should mimic thec structures, functions, and processes found in nature.

Matta C.S., Talla G., Hegde K.R., Gangopadhyay S.

Micro-drilling of Nitinol, a shape-memory alloy, presents unique challenges owing to its high strength, elasticity, and work-hardening properties. In addition, drill tip wandering caused by the radial force and radial torque during micro-drilling severely affects the hole quality. However, measuring the radial force and torque is difficult because of their low values. Therefore, the current study focuses on the measurement and analysis of radial force and radial torque and correlates them with hole quality characteristics. This study aims to examine the impact of micro-drilling parameters on hole quality when drilling Nitinol with carbide tools, to optimize conditions for better machining efficiency and precision. This is crucial given Nitinol’s widespread use in applications like medical devices requiring high precision. Additionally, hole quality affects component functionality, and this research aids in optimizing manufacturing by reducing material waste and improving yield. Micro-holes were drilled in Nitinol using the direct drilling method at varying speeds and feeds. The size effect during micro-drilling was characterized by the behavior of radial force, which fluctuated in relation to spindle speed. The “size effect” zones were recognized by the deformed layer’s pattern with respect to spindle speed. The measured oversize error exhibited a correlation with the radial force. The experimental results demonstrated a maximum oversize error of 8.5 µm at 30,000 rpm and 0.25 µm/rev and a minimum oversize error of 0.5 µm at 10,000 rpm and 0.075 µm/rev. The various zones in micro-drilling were differentiated by specific radial forces, which consequently explained the size effect phenomenon. The deformation layer thickness exhibited a maximum value of 6.113 µm at 20,000 rpm and 0.25 µm/rev and a minimum value of 3.211 µm at 10,000 rpm and 0.075 µm/rev. Scanning electron microscopy (SEM) revealed microcracks formed in the deformed layer at higher speeds. However, the ploughing and transition regions resulted in the material buildup with minimal or no cracks because of the size effect. Therefore, this study established a definite correlation between the size effect, radial force, radial torque, and hole quality characteristics.