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Mitigation of harmonics for five level multilevel inverter with fuzzy logic controller
Introduction. The advantages of a high-power quality waveform and a high voltage capability of multilevel inverters have made them increasingly popular in recent years. These inverters reduce harmonic distortion and improve the voltage output. Realistically speaking, as the number of voltage levels increases, so does the quality of the multilevel output-voltage waveform. When it comes to industrial power converters, these inverters are by far the most critical. Novelty. Multilevel cascade inverters can be used to convert multiple direct current sources into one direct current. These inverters have been getting a lot of attention recently for high-power applications. A cascade H-bridge multilevel inverter controller is proposed in this paper. A change in the pulse width of selective pulse width modulation modulates the output of the multilevel cascade inverter. Purpose. The total harmonic distortion can be reduced by using filters on controllers like PI and fuzzy logic controllers. Methods. The proposed topology is implemented with MATLAB/Simulink, using gating pulses and pulse width modulation methodology and fuzzy logic controllers. Moreover, the proposed model also has been validated and compared to the hardware system. Results. Total harmonic distortion, number of power switches, output voltage and number of DC sources are analyzed with conventional topologies. Practical value. The proposed topology has been very supportive for implementing photovoltaic based multilevel inverter, which is connected to large demand in grid and industry. M.S. Sujatha, S. Sreelakshmi, E. Parimalasundar, K. Suresh. -
Application of response surface methodology to optimize lead(Ii) ion adsorption by activated carbon fabricated from de oiled soya
Lead(II) ion a heavy metal is known for its toxicity. An initiative has been taken in this study, to adsorb toxic lead(II) ion using activated carbon made of de oiled soya, by an aqueous solution through batch adsorption methodology. Adsorption process variables such as adsorbent dose, contact time, solution pH, and lead(II) ion concentration were optimized by central composite design (CCD). To find the interaction between process variables, response surface plots were utilized using response surface methodology. Design-Expert software version 7 was resorted to in this experiment. It was observed that the components from the analysis of variance of the CCD revealed that the selective process independent variables had significant control over adsorption capacity. Desirability function was used to appraise the factors and response in adsorption experiments to find an optimum point where the preferred adsorption could be obtained. Adsorption process with the application of activated carbon developed from de-oiled soya meritoriously removed lead(II) ion with an optimum adsorption capacity of 26.279 mg/g for an initial concentration of lead(II) at 60 mg/L. 2021 Desalination Publications. All rights reserved. -
Exclusion of Chromium(VI) Ion in Grueling Activated Carbon Fabricated from Manilkara zapota Tree Wood by Adsorption: Optimization by Response Surface Methodology
The current paper makes obvious the elimination of chromium(VI) ion, from wastewater via adsorption technique with activated carbon generated from Manilkara zapota tree (MZTWAC). Preliminarily MZTWAC has undergone characterization studies which uncovered the suitability of MZTWAC to expel chromium(VI) from aqueous solution. Batch adsorption experimentation was premeditated with the competence of central composite design (CCD) and it was executed. Response surface methodology (RSM) was the key optimization software to appraise the adsorptive chattels of MZTWAC engaged in removing chromium(VI) ion in aqueous solution which explored the interactions flanked between four expounding variables explicitly initial concentration of chromium(VI) ion, pH of the solution, MZTWAC dose and time of exposure, and contact time. The response variable that was concentrated in the study was adsorption capacity. It was deduced a polynomial in quadratic equation was documented amid the adsorption capacity and variables influencing the adsorption with R2=0.9792 which was projected as the best suit for the adsorption process. ANOVA that is expanded as analysis of variance judged the connotation of adsorption process variables. 0.2 g of MZTWAC dosage has removed 87.629% chromium(VI) from aqueous solution. The enhancement of adsorption process reclined on the attainment of maximum adsorption capacity which further depends on the optimization of variables under consideration. This criterion was accomplished by the desirability function optimizing the process variables. 2022 S. Sujatha et al. -
Free vibration studies of box type laterite masonry structures
Vol.39, N0.3, /august -September 2012 pp 332-346 -
Studies on Uniaxial Compressive Strength of Laterite Masonry Prisms
Vol-04, No.02, April ISNN: 0974-5904 -
Indias Outward FDI: Macro-economic Determinants of Home Country
Nevertheless, a gap in the literature remains on the choice of investment destination and rationale backing the investment of Indian MNEs. The study examines the diverse home country determinants of outward FDI from low-and middle-income economies also the motive behind the investment of MNEs, which gained little attention in empirical studies. The role of home country determinants investigated for the most recent period, 1991-2019, using a panel data econometric framework. Results indicate that the home country's economic development level, globalization, political risk and science and technology investments significantly correspond to outward FDI from low-and middle-income countries. The present study analysis recommended that low and middle income governments provide incentivesto attract and retain FDI. Indian Institute of Finance. -
Transformation of India as investor of outward fdi: A systematic investigation of literature
Besides the economic transformation and industrial up-gradation, Indian enterprises have steadily intensified their overseas investment venture during recent years. A systematic literature review performed to inspect the strategic motives and Outward FDI (OFDI) impact on emerging economies like India. This paper explores relevant theories, strategic rationale, and economic policies that propel the present OFDI trend from India. The effort taken by the Indian government to promote innovations were Cross border commercial and industrial collaboration. These efforts flagged the way for more Outward FDI possibilities in the future (Welch, 1988). This study comprises the literature works till the year 2019, which includes research journals and reports. The analysis observes that knowledge-based industries drive India's Outward FDI and examine whether knowledge-based industries contribute to sustaining long-term domestic and international growth (Pradhan J.P., 2005; Narayanan, 2016). Indian Institute of Finance. -
An efficient adaptive reconfigurable routing protocol for optimized data packet distribution in network on chips
The deadlock-free and live lock-free routing at the same time is minimized in the network on chip (NoC) using the proposed adoptive reconfigurable routing protocol (ARRP). Congestion condition emergencies are avoided using the proposed algorithm. The input packet distribution process is improved among all its shortest paths of output points. The performance analysis has been initiated by considering different configuration (N*N) mesh networks, by sending various ranges of data packets to the network on chip. The average and maximum power dissipation of XY, odd-even, Dy-XY algorithm, and proposed algorithm are determined. In this paper, an analysis of gate utilization during data packet transfer in various mesh configurations is carried out. The number of cycles required for each message injection in different mesh configurations is analyzed. The proposed routing algorithm is implemented and compared with conventional algorithms. The simulation has been carried out using reconfigurable two-dimensional mesh for the NoC. The proposed algorithm has been implemented considering array size, the routing operating frequency, link width length, value of probability, and traffic types. The proposed ARRP algorithm reduces the average latency, avoids routing congestion, and is more feasible for NoC compared to conventional methods. 2024 Institute of Advanced Engineering and Science. All rights reserved. -
Corrosion studies on low-cost solid lubricant coated stainless steel specimen
AISI 304 stainless steel is widely used in industries owing to its many desirable qualities like excellent formability, drawability and resistance to corrosion. However, AISI 304 stainless steel corrodes when exposed to halide environment such as chloride and fluoride. This study is primarily focused to assess the anti-corrosion properties of AISI 304 steel when coated with CaF2 solid lubricant. CaF2 solid lubricant was synthesized from the discarded egg-shells by ion exchange method by treating the egg-shell powder with hydrogen fluoride solution. Thermal spray coating method was used to coat the synthesized CaF2 solid lubricant on the AISI 304 stainless steel specimen. Slurry erosion test and electrochemical impedance spectroscopy test were conducted on the coated and uncoated specimen to assess the corrosion resistance. From the experimental results, the corrosion rate of the coated specimen was found to be very effective compared to the uncoated specimen. 2023 Elsevier Ltd. All rights reserved. -
Experimental and finite element analysis of thermal stress on thermal spray coated AISI 304 stainless steel specimen using low cost solid lubricant
The scope of this work is to investigate the thermal stress on the CaF2 coated AISI 304 stainless steel substrate using both finite element analysis and experimental method. The influence of temperature and coating thickness on the thermal stress was investigated by conducting the test at different temperatures ranging from 100C to 1000C and by varying the coating thickness at 250, 350 and 450m. Stoneys equation was then used to investigate the thermal stress analytically and the finite element analysis results were then compared with the analytical results. From the experimental results it was found that the specimen coated with 450m coating thickness has better resistance to thermal stress compared to other samples taken for investigation. The experimental results were then validated to confirm the effectiveness of the coating thickness by conducting a confirmation test using thermal shock test to validate the results experimentally. The samples after the thermal shock test were examined using SEM, revealing numerous cracks, voids and peel off of the coating as the major reason for higher thermal stress on samples coated with 250 and 350m. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2023. -
PCR and Bio-signature for data confidentiality and integrity in mobile cloud computing
Cloud computing technology got relevance as computing paradigm, which delivers massively scalable computing technologies based on the Internet for the organizations. Mobile Cloud Computing (MCC) allows users more possibilities to access services conveniently. But data security and privacy issues still act as barriers for adoption to cloud technology when dealing with confidential data. Encryption techniques play a significant role in ensuring data security in the Cloud. Various data encryption techniques have been evolved till the date of which DNA Computing techniques got wider acceptance due to biological complexity and computational properties of DNA. These features can be exploited to solve data security issues in MCC. This paper highlights the security issues in the MCC and proposes biocomputing solution approaches to address data security. A methodology is proposed based on the principle concepts of polymerase chain reaction and primer generation for ensuring data confidentiality and integrity. The security analysis of the proposed cryptosystem is evaluated by theoretical analysis, complexity and probability analysis. Formal analysis of the proposed protocol is done using Scyther and all the modeled claims are validated and positive results are obtained. 2018 The Authors -
Segregating direct and indirect dimensions in ecosystem services valuation: The case of a coastal wetland ecosystem of south india
This paper provides insights into the multiple (direct and indirect) benefits of Kuttanad coastal wetland ecosystem in Kerala. Total annual direct ecosystem services generated from the wetlands are INR 8.45 billion or USD 0.11 billion per annum at 2020 prices. The estimates of the case study indicate that the annual value of indirect ecosystem services is thrice of direct provisioning services (Rs 22.52 billion or USD 0.31 billion per annum at 2020 prices). The valuation study would improve the knowledge and awareness of economic importance of wetland ecosystems among the various stakeholders including the policy makers of the society and their sustainable management to benefit the society. 2021 Ecological Society of India. All rights reserved. -
Climate Change inflicted Environmental Degradation leading to the Crumbling of Arctic Ecosystem
The Arctic and Antarctic regions serve as the air conditioners of planet Earth. The polar regions located thousands of miles away from us determine the climatic patterns of our geographical area. They maintain our planet at bearable temperatures which are ideal for the existence of diverse flora and fauna and to support different types of ecosystems all around the world. Apart from controlling the temperatures, they also regulate ocean currents which in turn have an effect on the monsoons, winds, hurricanes etc. The poles were pristine till a few decades back. Due to mans greed, the poles started deteriorating at an alarming scale. Climate change, biodiversity changes, oil drilling, seismic testing, toxin accumulation are a few of the challenges faced by the Arctic ecosystem having serious effects on its topography, terrestrial and marine life-forms and the whole ecosystem. Due to the alarming scale of global warming, there is also the danger of permafrost meltdown which can unleash a plethora of dangerous pathogens buried underneath and also let out the huge amounts of locked down carbon. The crumbling of the polar ecosystem is leading to rampant consequences not only in the poles but also elsewhere in the world thousands of miles away. Here, we attempt to discuss the repercussions of the crumbling Arctic ecosystem due to the physical, chemical and geological changes caused by such anthropogenic activities and look at the efforts being carried out to save the Arctic ecosystem in a frantic effort to save our planet. 2024, World Researchers Associations. All rights reserved. -
GCMS Analysis and zebrafish studiesr reveal presence of antilipidemic phytochemicals in methanolic seed extracts of phaseolus vulgaris /
International Journal of Pharmacy And Biological Sciences, Vol.9, Issue 2, pp.796-802, ISSN No: 2230-7605. -
An ancestral genomic locus in Mycobacterium tuberculosis clinical isolates from India hints the genetic link with Mycobacterium canettii /
International Microbiology, Vol.23, pp.397–404, ISSN No: 1139-6709. -
Winning battles with a joke: a qualitative inquiry of humour in the Indian Army
Humour in military organizations can be antithetical given the rigid hierarchy, high degrees of work formalization, and obedience to hierarchy. This paper explores how humour is initiated, propagated and maintained in the Indian Army. We conducted twelve in-depth interviews with retired army professionals and used Braun and Clarkes (2006) thematic analysis to capture the study's main findings. Three major themes emerged organizational humour, leader humour, and team humour. We found humour is essential in combating stress, increasing social cohesion, facilitating newcomer assimilation, and promoting a positive work environment. We also found evidence of subversive humour used in forms of resistance to challenge the hierarchical structure subtly. We have provided a three-part schema of workplace humour which sheds interesting insights on workplace humour. Our findings will contribute to understanding how military humour helps to maneuver challenges of a stressful work situation 2023,European Journal of Humour Research. All Rights Reserved. -
Benzimidazole and benzothiazole fluorophores with large Stokes shift and intense sky-blue emission in aggregation as Al3+ and Pb2+ sensors
New fluorophores based on 2-(2?-hydroxyphenyl)benzimidazole (HBZ) and 2-(2?-hydroxyphenyl)benzothiazole (HBT) for metal ion sensing were designed and synthesized using a simple method. The photophysical behaviour of these fluorophores were investigated in various solvents using UVvisible and fluorescence spectra. All the heterocycles showed strong excited state intramolecular proton transfer (ESIPT) characteristics with remarkably large Stokes shift (190252 nm). Spatial charge distribution in the frontier molecular orbitals also demonstrated the ESIPT mechanism through intramolecular charge transfer. Time resolved fluorescence measurements for these heterocycles showed two long-life decay mechanisms which may be attributed to excited state enol and keto emission. These intense sky-blue emitters also exhibited aggregation induced blue shifted emissions due to restriction of intramolecular rotation processes. Fluorescence sensing studies for metal ions revealed the good selectivity of these fluorophores towards Al3+ and Pb2+. Theoretical computations performed using density functional theory methods showed two possible geometric configurations for Al3+ binding. 2019 Elsevier B.V. -
Benzimidazole and benzothiazole conjugated Schiff base as fluorescent sensors for Al3+ and Zn2+
Two benzimidazole/benzothiazole based azomethines, (E)-2-(1H-benzo[d]imidazol-2-yl)-4-(4-(diethylamino)-2-hydroxybenzylideneamino)phenol (HBZA) and (E)2-(benzo[d]thiazol2-yl)4-(4-(diethylamino)2-hydroxybenzylideneamino)phenol (HBTA) were designed and synthesised. Investigations of solvatochromic behaviour of these fluorophores in solvents of varying polarities showed large Stokes shift of 134210 nm. Time resolved Laser induced fluorescence measurements revealed the excited state dynamics of the fluorophores. Molecules were also found to be emissive in aggregated state as seen from the aggregation induced emission studies. Appreciable absorption and emission spectral changes upon co-ordination of HBZA with Al3+/Zn2+ and HBTA with Al3+, as well as good sensitivity and selectivity, indicated their capability of detecting the two analytes. The binding stoichiometry was determined using electrospray ionization mass spectrometry (ESI-MS) and the binding mechanism was studied using density functional theory. 2019 Elsevier B.V. -
Structural investigation, spectroscopic and energy level studies of Schiff base: 2-[(3?-N-salicylidenephenyl)benzimidazole] using experimental and DFT methods
The Schiff base 2-[(3?-N-salicylidenephenyl)benzimidazole] (Spbzl) was characterized by FT-Raman, 1H NMR, 13C NMR and single crystal X-ray diffraction technique. Crystallographic studies reveal the presence of two water molecules in the asymmetry unit which aid the intermolecular hydrogen bonding with imidazole ring, and the trans-conformation of the azomethine bond. Theoretical computations conducted using density functional theory (DFT) analysis support the experimental facts. Energy levels estimated by DFT studies are in good agreement with the values obtained from cyclic voltammetry technique. Frontier molecular orbital analysis shows that charge transfer has taken place from donor to acceptor moiety, which is also supported by the high hyperpolarizability values in both gaseous and solution phases, indicating high charge transfer capability of the molecule. A comparative theoretical study of Spbzl with derivative 4-((3-(1H-benzimidazol-2-yl)phenylimino)methyl)-3-hydroxybenzoic acid (Pbzlb) having an added anchor group COOH substituted at para position in the acceptor ring has been made. The result shows the feasibility of charge transfer to the semiconductor surface in dye sensitized solar cell (DSSC) applications for Pbzlb. 2017 Elsevier B.V. -
Effect of solvents on photophysical properties and quenching of 2-{[3-(1H-benzimidazole-2-yl) phenyl] carbonoimidoyl}phenol
The effect of solvents of varying polarity on the absorption and fluorescence emission of the Schiff base, 2-{[3-(1H-benzimidazole-2-yl) phenyl]carbonoimidoyl}phenol, was studied using Lippert-Mataga bulk polarity function, Reichardt's microscopic solvent polarity parameter and Kamlet's multiple linear regression approach. The spectral properties follow Reichardt's microscopic solvent polarity parameter better than Lippert-Mataga bulk polarity parameter, indicating the presence of both general solute-solvent interactions and specific interactions. Catalan's multiple linear regression approach indicates the major role of solvent polarizability/dipolarity influence compared with solvent acidity or basicity. The solvatochromic effect was utilized to calculate the dipole moments of ground and excited states of the Schiff base using different methods. Bathochromic shift in the emission spectrum and the increase in dipole moment in the excited state signifies the intramolecular charge transfer character in the emitting singlet state. Fluorescence quenching by aniline was also studied in 1,4-dioxane and n-butanol, and the results were analyzed using sphere of action static quenching and finite sink approximation models. 2014 John Wiley & Sons, Ltd.