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Speech to text conversion and summarization for effective understanding and documentation
Speech, is the most powerful way of communication with which human beings express their thoughts and feelings through different languages. The features of speech differs with each language. However, even while communicating in the same language, the pace and the dialect varies with each person. This creates difficulty in understanding the conveyed message for some people. Sometimes lengthy speeches are also quite difficult to follow due to reasons such as different pronunciation, pace and so on. Speech recognition which is an inter disciplinary field of computational linguistics aids in developing technologies that empowers the recognition and translation of speech into text. Text summarization extracts the utmost important information from a source which is a text and provides the adequate summary of the same. The research work presented in this paper describes an easy and effective method for speech recognition. The speech is converted to the corresponding text and produces summarized text. This has various applications like lecture notes creation, summarizing catalogues for lengthy documents and so on. Extensive experimentation is performed to validate the efficiency of the proposed method. Copyright 2019 Institute of Advanced Engineering and Science. All rights reserved. -
Speech disabilities in adults and the suitable speech recognition software tools - A review
Speech impairment, though not a major obstacle, is still a problem for people who suffer from it, while they are making public presentations. This paper describes the different speech disabilities in adults and reviews the available software and other computer based tools that facilitate better communication for people with speech impairment. The motivation for this writing has been the fact that stuttering, one of the types of speech disability has affected about 1 percentage of the people worldwide. This fact was provided by the Stuttering Foundation of America, a Non-profit Organization, functioning since 1947. A solution to stuttering is expected to benefit a considerable population. Speech recognition software tools help people with disabilities use their computers and other hand held devices to satisfy their day-to-day needs which otherwise, require dedicated domestic help and also question the person's ability to be independent. ASR (Automatic Speech Recognition) systems are popular among the common people and people with motor disabilities, while using these techniques for the treatment of speech correction is a current research field and is of interest to SLPs/SLTs (Speech Language Pathologist / Speech Language Therapist). On-going research also includes development of ASR based software to facilitate comfortable oral communication with people suffering from speech dysfunctions, i.e., in the domain of AAC (Augmentative and Alternative Communication). 2015 IEEE. -
Speculative investment decisions in cryptocurrency: a structural equation modelling approach
Cryptocurrency markets are inclined towards speculative usage due to the inherent high risk of financial loss and the potential for substantial gains during transaction completion. In response to this phenomenon, this study represents the inaugural effort to explore the influence of variables such as subjective norms, domain knowledge, impulsive investment tendencies, and self-control on decisions related to speculative investments. Utilising structural equation modelling with a dataset of 367 responses in India, the study is the first of its kind. The research reveals that subjective norms and domain knowledge play a significant role in influencing impulsive investment and self-control. Additionally, impulsive investment exhibits significant associations with decisions involving speculative investments. This insight underscores the complexity wherein individuals, despite exercising self-control, may still engage in speculative decisions that lead to adverse consequences. The findings have practical implications for investors and regulators, offering valuable insights into investment behaviours within the cryptocurrency realm. 2024 Informa UK Limited, trading as Taylor & Francis Group. -
Specular Reflection Removal Techniques in Cervix Image: A Comprehensive Review
Cancer detection through medical image segmentation and classification is possible owing to the advancement in image processing techniques. Segmentation and classification tasks carried out to predict and classify diseases need to be dependable and precise. Specular reflections are the high-intensity and low-saturation areas that reflect the light from the probing devices that capture the picture of the organ surface. These areas sometimes mimic the features that are key identifying factors for cancers like acetowhite lesions. This review article examines the various methods proposed for removing specular reflections from medical images, especially those captured by colposcope. The fundamentals of specular reflection removal and its associated challenges are discussed. The paper reviews several state-of-the-art approaches for specular reflection removal. The comprehensive review can be a strong foundation for researchers looking to decide on appropriate techniques to employ in their respective research approaches. 2024, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. -
Spectrum of corona products based on splitting graphs
Let G be a simple undirected graph. Three new corona products of graphs based on splitting graph of G are defined. The adjacency spectra of the three new graphs based on splitting graph of G are determined. The number of spanning trees and the Kirchoff index of the new graphs are determined using their nonzero Laplacian eigenvalues. 2023 World Scientific Publishing Company. -
Spectroscopic, crystal structure and DFT-assisted studies of some nickel(II) chelates of a heterocyclic-based NNO donor aroylhydrazone: in vitro DNA binding and docking studies
Five new nickel(II) complexes have been synthesised with an NNO donor tridentate aroylhydrazone (HFPB) employing the chloride, nitrate, acetate and perchlorate salts, and all the complexes are physiochemically characterized. Elemental analyses suggested stoichiometries as Ni(FPB)(NO3)]2H2O (1), [Ni(HFPB)(FPB)]Cl (2), [Ni(FPB)(OAc)(DMF)] (3), [Ni(FPB)(ClO4)]DMF (4), [Ni(FPB)2] (5). Aroylhydrazone is found coordinating in deprotonated iminolate form in four of the complexes (1, 3, 4, 5) however in one case (complex 2), two aroylhydrazone moieties are binding to the metal centre in the neutral and anionic forms. The structure of the bisligated complex 5, found using single crystal X ray diffraction studies confirmed that the metal has a distorted octahedral N4O2 coordination environment, with each of the two deprotonated ligands coordinating through the pyridine nitrogen, imino-hydrazone nitrogen and the enolate oxygen of the hydrazone moiety. To compare and study, the electronic interactions and stabilities of the metal complexes, various quantum chemical parameters were calculated. Moreover, Hirshfeld surface analysis was carried out for complex 5 to determine the intermolecular interactions. The biophysical attributes of the ligand and complex5 have been investigated with CT-DNA and experimental outcomes show that the Ni(II) complex exhibited higher binding propensity towards DNA as compared to ligand. Furthermore, to specifically understand the type of interactions of the metal complexes with DNA, molecular docking studies were effectuated. In addition, the electronic and related reactivity behaviors of the ligand and five Ni(II) complexes were studied using B3LYP/631 + + G**/LANL2DZ level. As expected, the obtained results from Natural Bond Orbital (NBO) computations displayed that the resonance interactions (n ? ?* and ? ? ?*) play a determinant role in evaluating the chemical attributes of the reported compounds. Graphical abstract: (Figure presented.). The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023. -
Spectroscopic Study Of Selected Be Stars In Our Galaxy
The optical spectroscopic monitoring observation of two Be stars namely 4 Hercules and 88 Hercules was observed with 1.02m telescope at the VBO, Tamil Nadu, India over a period of six months. The spectra were reduced using standard routines in IRAF. The equivalent width of the lines were identified have been measured. The line profile variability exhibited by H? H?and HeI lines are studied to understand the emission mechanism in the Classical Be-stars. The properties of the process can be well constrained, leaving only few options, most importantly, but not exclusively, non-radial pulsation and small scale magnetic fields. In different stars different processes may be acting. This is not only true for the disk structure, but as well for its variability, both cyclic and secular. Be stars, at lower metallicities, seem more common and more rapidly rotating. The Be phenomenon, linked with one or more mass ejection processes, acts on top of a rotation rate of about 75% of critical or above. In this work, first the definition of Be-stars is contrasted to similar classes, and common observables obtaind for Be-stars are introduced and the respective formation mechanism explained. The current state of knowledge concerning the central stars as non-radially pulsating objects and non-magnetic stars, as far as it concerns large scale. The weak magnetic fields remain possible, but are of yet unproven. In this dissertation Chapter 1 discusses the features of Be- stars and reviewed the progress made in understanding Be-stars in the recent past. Chapter 2 discusses the literature review. Chapter 3 describes the methodology carried out to study the objective. Chapter 4 explains the result and analysis part of the research. Chapter 5 is about the conclusions. -
Spectroscopic Study of Late-type Emission-line Stars Using the Data from LAMOST DR6
Low-mass emission-line stars belong to various evolutionary stages, from pre-main-sequence young stars to evolved stars. In this work, we present a catalog of late-type (F0 to M9) emission-line stars from the LAMOST Data Release 6. Using the scipy package, we created a Python code that finds the emission peak at H? in all late-type stellar spectra. A data set of 38,152 late-type emission-line stars was obtained after a rigorous examination of the photometric quality flags and the signal-to-noise ratio of the spectra. Adopting well-known photometric and spectroscopic methods, we classified our sample into 438 infrared (IR) excess sources, 4669 post-main-sequence candidates, 9718 Fe/Ge/Ke sources, and 23,264 dMe sources. From a crossmatch with known databases, we found that 29,222 sources, comprising 65 IR excess sources, 7899 Fe/Ge/Ke stars, 17,533 dMe stars, and 3725 PtMS candidates, are new detections. We measured the equivalent width of the major emission lines observed in the spectra of our sample of emission-line stars. Furthermore, the trend observed in the line strengths of major emission lines over the entire late-type spectral range is analyzed. We further classified the sample into four groups based on the presence of hydrogen and calcium emission lines. This work presents a large data set of late-type emission-line stars, which can be used to study active phenomena in late-type stars. 2024 National Astronomical Observatories, CAS and IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
Spectroscopic study of Herbig Ae/Be stars in the Galactic anti-centre region from LAMOST DR5
We study a sample of 119 Herbig Ae/Be stars in the Galactic anti-centre direction using the spectroscopic data from large sky area multi-object fiber spectroscopic telescope survey program. Emission lines of hydrogen belonging to the Balmer and Paschen series, and metallic lines of species such as Fe ii, O i, Ca ii triplet are identified. A moderate correlation is observed between the emission strengths of H? and Fe ii 5169 suggesting a possible common emission region for Fe ii lines and one of the components of H?. We explored a technique for the extinction correction of the HAeBe stars using diffuse interstellar bands present in the spectrum. We estimated the stellar parameters such as age and mass of these HAeBe stars, which are found to be in the range 0.1-10 Myr and 1.5-10 M, respectively. We found that the mass accretion rate of the HAeBe stars in the Galactic anti-centre direction follows the relation ?acc ? M?3.12-0.34+0.21, which is similar to the relation derived for HAeBe stars in other regions of the Galaxy. The mass accretion rate of HAeBe stars is found to have a functional form of ?acc ? t-1.10.02 with age, in agreement with previous studies. 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
Spectroscopic study of Be-shell stars: 4 Her and 88 Her
We present an optical spectroscopic study based on 41 spectra of 4 Her and 32 spectra of 88 Her, obtained over a period of 6 months. We estimate the rotational velocity of these stars from HeI lines in the blue spectral region (4000-4500 . We find that these stars are likely to be rotating at a fractional critical rotation of ?0.80. We measure the average I p/I c ratio to quantify the strength of the H? line and obtain 1.63 for 4 Her and 2.06 for 88 Her. The radius of the H? emission region is estimated to be Rd/R? ?5.0, assuming a Keplerian disk. These stars are thus found to be fast rotators with a relatively small H? emission region. We detect V/R variation of the H? spectral line during the observed period. We re-estimate the periods for both stars and obtain a period of ?46 d and its harmonic of 23.095 d for 4 Her, and a period of ?86 d for 88 Her. As these two cases are shell stars with binaries and have low H? EW with the emission region closer to the central star, the V/R variation and a change in period may be an effect of the binary on the circumstellar disk. 2016 National Astronomical Observatories, Chinese Academy of Sciences and IOP Publishing Ltd. -
Spectroscopic Studies on Structurally Modified Anthraquinone Azo Hydrazone Tautomer: Theoretical and Experimental Approach
A series of unique four mono-azo substituted anthraquinone analogue were synthesized by using the anthraquinone components in the diazo-coupling technique. The FT-IR, 1H NMR, and HRMS, data were used to confirm the structure of the molecules, and spectroscopic techniques like UV-Vis, and photoluminescence spectroscopy were employed to estimate the photophysical properties of the molecules. The molecular optimized geometry and frontier molecular orbitals were estimated using density functional theory. Further, global chemical reactivity descriptors parameter was theoretically estimated using the value of the highest occupied molecular orbit and lowest unoccupied molecular orbits. The anti-tubercular action of the synthesised dyes were also examined. The results of this biological activity showed that N-isopropyl aniline combined with anthraquinone N-isopropyl aniline had superior anti-tubercular activity when compared to Rifampicin as the standard. As per molecular docking studies, the synthesized compound Q1 showed excellent binding energy (-10.0kcal/mol) among all compounds against the 3ZXR Protein. These results agreed with our in-vitro anti-TB activity results. 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
Spectroscopic Studies of Galactic Field Be Stars
Be stars provide excellent opportunity to study circumstellar disks. But the disc formation mechanism of classical Be (CBe) stars- the Be phenomenon- is still poorly understood. This can be understood by studying CBe stars in various locations like clusters and fields. Spectra of Be stars show interesting emission lines of different elements like hydrogen, helium, iron, oxygen calcium, etc. These emission lines are valuable indicators in providing information about the circumstellar disks of Be stars. In the past several decades various aspects of Be stars have been studied. But literature review clearly indicates the need of further studies to frame a consolidated picture about Be phenomenon in CBe stars. It is found that especially, the region ?????? 7500 - 8800 ??? is a less studied, and thus poorly understood area in Be star research. But this area shows some interesting features like emission lines calcium, iron, oxygen and Paschen series. So, here we have studied a sample of 118 field CBe stars taken from the catalogue of Jaschek & Egret (1982) and whose medium resolution spectra were obtained in ?????? 3800 ?? 9000 ??? region during December, 2007 to January, 2009 with the 2.1-m Himalayan Chandra Telescope (HCT), located at Hanle, Ladakh, India and operated by the Indian Institute of Astrophysics (IIA), Bangalore. In this thesis, we present three works which investigate the disc properties of our 118 program Be stars by studying their spectral line features, focussing primarily on the less explored ?????? 7500 - 8800 ??? region. Firstly, we have analyzed the less studied Fe II 7712 ??? emission line for our stars to understand the possible Fe II line excitation mechanism in CBe stars. Our work predicts that Ly???fluorescence may be the possible Fe II line excitation mechanism in CBe stars. Secondly, we have studied the Ca II triplet emission lines for our stars and have developed a new technique for deblending Ca II components from their counterpart Paschen lines, thus providing a more efficient way to analyze Ca II lines. Analyzing Ca II lines through this technique, we suggest that the gas producing these lines is optically thick. This leads us to predict that Ca II lines may be an indicator of binarity in Be stars. Lastly, we have estimated the Balmer decrement values, D34 and D54 for 81 of our sample stars to shed light on opacity effects in Be star disks. Our work confirms the disc transient nature of Be stars through epoch-wise D34 and D54 variation study and also suggests that Be star disks are optically thick. -
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Spectroscopic Studies and Theoretical Analysis of Some Selected Heterocycles
Seven derivatives of heterocycles benzimidazole, benzoxazole and benzothiazole were studied, five of which were synthesized and characterized. The molecular geometry and newlinespectroscopic data of the compounds in the ground state were calculated using the density functional theory (DFT/B3LYP) method with the 6-311++G(d,p) basis set. A comparison between the experimental and calculated data was attempted. Molecular electrostatic potential (MEP) and global reactivity parameters were deduced using theoretical calculations. HOMO-LUMO energy gap for each compound was determined by DFT and cyclic voltammetry. The cyclic voltammograms were recorded in acetonitrile solvent using lithium perchlorate as the supporting electrolyte. For all the compounds experimentally determined HOMO LUMO energy gap in polar solvent was lesser than that from DFT calculated energy gap. Using the HOMO-LUMO energy gap, global reactivity parameters were calculated. The effect of solvents of varying polarity on the absorption and emission spectra of the compounds was studied. Large excitation and emission energy differences were observed for all the selected heterocycles. The excitation and fluorescence spectra of selected heterocycles were recorded in eight solvents of different solvent polarity. It is evident from the excitation spectra that on increase of the solvent polarity, a bathochromic shift takes place for and#960;-and#960;* transition, and this is attributed to the high influence of solvent polarity in the excited state of heterocycle newlinecompared to its ground state. The dipole moments in the ground and the first excited state of heterocycle derivatives were newlinecalculated using Lippert-Mataga and Kawski-Chamma-Viallet methods. Guggenheim-Debye method was adopted to calculate ground state dipole moment. The dipole moments of the compounds were also calculated using Time Dependent-Density Functional Theory (TD-DFT). The dipole moment values of the compounds suggested that the excited state has more charge separation and thus becomes more polar. -
Spectroscopic parameters of red emitting Eu3 +-doped La2Ba3B4O12 phosphor for display and forensic applications
Eu3+-activated La2Ba3B4O12 (LBBO) phosphor was synthesized by the solid-state reaction method. LBBO phosphors characterized by structural analysis (X-ray diffraction), including refinement parameters and crystallite size, morphological analysis by (Scanning Electron Microscopy and Transmission Electron Microscopy). Photoluminescence (PL) studies of synthesized phosphors monitored in the range of 450-675 nm for the LBBO phosphor doped with Eu3 +. An excitation peak was found at 254nm and several sharp emission peaks were found around 466, 541, 588, 593, 613, and 626nm with high intensities. The crystallite size of the Eu3 +-doped LBBO phosphor was around 126nm. It is found that the intense emission peak is in the red region. The detailed processes involved and a possible mechanism for the PL are studied and discussed. The phosphor can also be used in forensic science to detect fingerprints. 2021 Elsevier Ltd All rights reserved. -
Spectroscopic investigation on shuttlecock-shaped liquid crystalline trimers: Mesomorphic behaviour and its application in optical storage devices
In this paper, we discuss the synthesis and characterization of 2,3,4-tris[n-((4-(-cyanophenyl)diazenyl)phenoxy)alkyloxy]benzonitrile obtained by coupling 2,3,4-trihydroxy benzonitrile and (E)-4-((4-((n-bromoalkyl)oxy)phenyl)diazenyl)benzonitrile, pertain to shuttlecock shaped liquid crystals. The molecular structure was confirmed by NMR spectroscopic and elemental analyzer. The thermal behavior of the trimers was assessed using a polarizing optical microscope (POM) and differential scanning calorimetry (DSC). The three diazo groups in the trimers enabled us to study the photo-isomerization effect and evaluate their potential applications in optical storage devices. Importantly, we found these trimers easy to synthesize and process, paving the way for cost-effective alternatives to traditional LC materials. We fabricated an optical storage device to study the light effects on shuttlecock-shaped LC trimers, demonstrating that the geometry of the trimers plays a crucial role in determining structure-property relationships. 2024 -
Spectroscopic and TDDFT investigation of highly selective fluoride sensors by substituted acyl hydrazones
In this work, we report the synthesis of two receptors for fluoride ions based on acyl hydrazone, such as N?-[(1Z)-1-(4-fluorophenyl)ethylidene]benzohydrazide (R1) and N?-[(1Z)-1-(2-hydroxyphenyl)ethylidene]benzohydrazide (R2). The receptors R1 and R2 were synthesized from the corresponding ketones and benzoic acid hydrazide and characterized spectroscopically by UVvisible, IR and 1HNMR techniques. The response of R1 and R2 towards different anions was studied colourimetrically in acetonitrile. The receptors exhibited a specific response towards fluoride ions. Further studies of 1:1 composition of receptors, R1/R2:fluoride ions by different spectroscopic techniques such as UVVisible, IR and 1HNMR spectroscopy indicated the participation of -NH proton of the receptors in the sensing action through the hydrogen bonding. To understand the mechanism, Time-Dependent Density Functional Theory (TD-DFT) studies were done using the CAM-B3LYP/6311G++ (3df,2p) with Grimme's D3BJ empirical dispersion basis set. The studies supported the role of hydrogen bonding interaction of -NH and-OH protons of the receptors with the fluoride ions. 2020 Elsevier B.V. -
Spectroscopic analysis of lead borate systems
Oxide glass systems are interesting because of their bonding like bridging and non-bridging oxygens. Depending on the modifier, the B2O3 glass system can have various Boron-Oxygen network. It is found that, PbO modifies the borate network and increases the formation of penta and diborate groups. In this work, we investigated optical properties of Lead Borate glass systems (x PbO: (1-x) B2O3) with x varying from 30-85 mol % using UV-VIS Spectra and the corresponding band gap was estimated using Tauc relation and these systems behave like direct allowed band gap systems. These results show that, Eg decreases with the addition of lead content. Further the refractive index measurements also have been carried out at various wavelengths. Many correlation is found between the band gap and refractive index for different compositions. Using different theoretical models a best fit has been tried and Ravindra's relation is found to match with our experimental results. 2018 Author(s). -
Spectrochemical and theoretical approaches for acylhydrazone-based fluoride sensors
Abstract: Acylhydrazone derivatives N?-[1-(2-fluorophenyl)ethylidene]pyridine-3-carbohydrazide (R1) and N?-[2-fluorobenzylidene]benzohydrazide (R2) were synthesized from their corresponding hydrazides and characterized by spectroscopic methods. The response of these acylhydrazones towards different anions was studied by colorimetric and spectrofluorometric methods in acetonitrile. The receptors exhibited a specific response towards fluoride ion. The binding affinity of the receptors with fluoride anion was studied by fluorescence spectroscopic techniques and abinitio density functional theory calculations with Beckers three-parameter LeeYangPar (B3LYP) exchange functional with 6-311G basis set. Graphical abstract: [Figure not available: see fulltext.]. 2018, Springer Nature B.V. -
Spectro-temporal and type I X-ray burst analysis of GX 3+1 using AstroSat observations
GX 3+1, an atoll type neutron star low-mass X-ray binary, was observed four times by Soft X-ray Telescope and The Large Area X-ray Proportional Counter on-board AstroSat between 2017 October 5 and 2018 August 9. The hardness-intensity-diagram of the source showed it to be in the soft spectral state during all the four observations. The spectra of the source could be adequately fit with a model consisting of blackbody (bbody) and powerlaw (powerlaw) components. This yielded the blackbody radius and mass accretion rate to be ?8 km and ?2 10?9 M? y?1, respectively. In one of the observations, a type I X-ray burst having a rise and e-folding time of 0.6 and 5.6 s, respectively, was detected. Time-resolved spectral analysis of the burst showed that the source underwent a photospheric radius expansion. The radius of the emitting blackbody in GX 3+1 and its distance were estimated to be 9.19 +?00.8297 km and 10.17 +?00.1807 kpc, respectively. Temporal analysis of the burst yielded upper limits of the fractional root mean square amplitude of 7 per cent, 5 per cent, and 6 per cent during burst start, burst maximum, and right after the radius expansion phase, respectively. 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.