Browse Items (5511 total)
Sort by:
-
Fault Analysis and Clearance in FL-APC DC-AC Converter; [Analyse et imination des dauts dans le convertisseur CC-CA FL-APC]
The traditional active neutral-point-clamped (APC) dc-ac converter maintains great common-mode voltage with high-frequency (CMV-HF) reduction capability, so it has limited voltage gain. This article presents a new five-level APC (FL-APC) dc-ac converter capable of voltage step-up in a single-stage inversion. In the suggested design, a common ground not only reduces the CMV-HF but also improves dc-link voltage usage. While comparing with traditional two-stage FL-APC dc-ac converter, the proposed design has lower voltage stresses and greater uniformity. While improving overall efficiency, the suggested clamped dc-ac converter saves three power switches and a capacitor. Modeling and actual tests have proven the suggested APC inverter's overall operation, efficacy, and achievability. The proposed circuit is finally tested with fault clearance capability. 2023 IEEE. -
Newly designed single-stage dual leg DC-DC/AC buck-boost converter for grid connected solar system
This paper proposes a novel single-stage buck-boost inverter based on dual leg. Modulation techniques, working principle, guidelines for components design, and guidelines are discussed and presented. A theoretical concept is initially tested in Simulink platform and practically verified with a test bench model. A practical model is developed to verify the simulation model and tested different modes of operation are analyzed. The main advantages of the proposed work are as follows: The number of passive components is less, switching frequency components are not high so leakage current is very less, and voltage control in a wide range is achieved without using a DC link capacitor. High efficiency can be achieved due to multi-stage operation. This proposed work is suitable for high/low voltage PV-based energy conversion. Electromagnetic interference is also reduced due to continuous input current. 2023 John Wiley & Sons Ltd. -
Design and implementation of dual-leg generic converter for DC/AC grid integration
A newly designed generic photo-voltaic (PV) DC-DC/DC-AC converter is for direct current (DC) grid or single-phase alternating current (AC) grid integration. Main concept of the proposed converter is universal power conversion, and the same converter is used for DC-DC/DC-AC applications which also aiming for minimum redundancy because the proposed converter can be able to produce DC and AC output from the fixed/variable DC source. The proposed converter is designed with single-stage dual leg topology, with a designed filter, and protection circuits are connected in output/grid side. The proposed circuit is compared with existing topologies, and comparative analyses are made in both chopper (DC-DC) and inverter (DC-AC) modes for universal or generic operation. Real-time implementation of the proposed model is prepared for the power rating of 3.5 KW during inverter mode and 4 KW when same circuit working in chopper mode. Hardware results are obtained from the model from both chopper and inverter modes. Finally, correct applications, advantages, and future work are concluded in the last section. 2023 John Wiley & Sons Ltd. -
IPWM Based IBMSC DC-AC Converter Using Solar Power for Wide Voltage Conversion System; [Convertisseur DC-AC IBMSC bassur l'IPWM et utilisant l'ergie solaire pour un syste de conversion large tension]
This article proposes isolated bidirectional micro dc-ac single phase controlled (IBMSC) converter based on in-phase-voltage pulsewidth modulation (IPWM). This resonant IPWM converter, ratio of voltage conversion can be controlled from 0 to ?. So, this converter is highly referred for huge range voltage conversion. However, voltage conversion ratio determines power transfer direction and duty ratio. Power flow direction and duty cycle value can be varying smoothly, so it is suitable for dc-ac bidirectional power conversion application. Inverter mode and also rectifier mode are possible from bidirectional operation, which is controlled by a unified current controller. The proposed solution can achieve smooth switching grid operation with high efficiency. Working principle, design procedure, control strategy, and characteristics of the proposed converter are implemented with a prototype model of power rating 500 W with a voltage range of 20-50 V to test the ability of withstanding. Performance, feasibility, and effectiveness of the proposed converter are tested with this hardware test-bench model. 2022 IEEE. -
Encapsulated 3converter for power loss minimization in a grid-connected system
A newly designed DCAC three phase bidirectional converter (DATBC) with an encapsulated DCDC converter (EDC) for the energy storage system (ESD) is analysed and investigated in this research paper. By using encapsulated or embedded or hidden DCDC converter a stable and constant DC bus is developed between the encapsulated DCDC converter and DCAC three phase bidirectional converter. The proposed converter is entirely different from the traditional dual-stage DCAC converter, because it takes less than 20% of power used for the DCAC conversion process. So, this reduced power consumption increases efficiency to a considerable value. A new control technique for zero sequence has been adopted components are inserted in the modulating signal based on carrier pulse width modulation (CPWM). Working principle, implementation and characteristics of the DCAC three phase bidirectional converter are analysed. Effectiveness and feasibility of the developed converter are examined with a proto-type model. 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. -
Design and implementation of a universal converter for microgrid applications using approximate dynamic programming and artificial neural networks
This paper introduces a novel design for a universal DC-DC and DC-AC converter tailored for DC/AC microgrid applications using Approximate Dynamic Programming and Artificial Neural Networks (ADP-ANN). The proposed converter is engineered to operate efficiently with both low-power battery and single-phase AC supply, utilizing identical side terminals and switches for both chopper and inverter configurations. This innovation reduces component redundancy and enhances operational versatility. The converter's design emphasizes minimal switch usage while ensuring efficient conversion to meet diverse load requirements from battery or AC sources. A conceptual example illustrates the design's principles, and comprehensive analyses compare the converter's performance across various operational modes. A test bench model, rated at 3000W, demonstrates the converter's efficacy in all five operational modes with AC/DC inputs. Experimental results confirm the system's robustness and adaptability, leveraging ADP-ANN for optimal performance. The paper concludes by outlining potential applications, including microgrids, electric vehicles, and renewable energy systems, highlighting the converter's key advantages such as reduced complexity, increased efficiency, and broad applicability. The Author(s) 2024. -
Design and Implementation Bidirectional DC-AC Converter for Energy Storage System
This article proposes a bidirectional single-phase dc-ac converter with triple port converter (T-PC) for application of energy storage. This proposed converter provides three ports such as ac port, dc port, and dc bus port to achieve three power interfacing ports. For the direct conversion process, dc port is directly connected to T-PC, and direct power will be exchanged between energy storage device (ESD) and grid when the ESD voltage peak amplitude is lower than the ac voltage. Thus, a dc-dc converter downstream power process gets reduced, and power loss is decreased considerably. Due to multilevel characteristics, switching losses in the T-PC can be reduced. The efficiency of the overall bidirectional dc-ac conversion process can be increased significantly. The circuit model, working principle, and modulation control of T-PC-based bidirectional dc-ac conversion concepts are analyzed. A 1.5-kW test-bench model is developed and its effectiveness is verified to find the merits of suggested conversion. 2021 IEEE. -
Migration, threats to identity and diminishing human dignity /
RESEARCH REVIEW International Journal of Multidisciplinary, Vol.5, Issue 2, pp.49-52, ISSN No. 2455-3085. -
Surface modified CaO nanoparticles with CMC/D-carvone for enhanced anticancer, antimicrobial and antioxidant activities
The rising prevalence of antimicrobial resistance and the continued challenge to cancer therapy are in desperate need of developing innovative therapeutic strategies. In this regard, the present research work focuses on the development of CaO NPs and CaO-CMC-Dcar nanocomposites for enhanced antimicrobial and anti-cancer activities. CaO nanoparticles were synthesized by facile one pot chemical approach and eventually functionalized with CMC and D-carvone biomolecules. XRD analysis revealed that the crystallite size for CaO and CaO-CMC-Dcar nanoparticles was found to be 21.18 nm and 17.02 nm respectively. The band gap values obtained for CaO and CaO-CMC-Dcar nanoparticles were 4.44 eV, and 4.25 eV respectively. The CaO-CMC-Dcar nanoparticles show absorption maxima at 292 nm, slightly red-shifted from bare CaO nanoparticles. HRTEM and SEM analysis revealed that the prepared samples were roughly spherical and agglomerated in nature. Antimicrobial activity was evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans. The zone of inhibition (ZOI) for CaO-CMC-Dcar nanoparticles against MRSA and C. albicans was 20.1 0.3 mm and 21.1 0.2 mm, respectively, significantly higher than that of pure CaO nanoparticles (14.1 0.2 mm and 13.2 0.1 mm) and comparable to standard anti-bacterial streptomycin and antifungal fluconazole discs. Anticancer activity was assessed via MTT assay against MOLT-4 blood cancer cells, where the IC50 values for CaO and CaO-CMC-Dcar nanoparticles were 22.6 ?g/mL and 21.54 ?g/mL, respectively. Additionally, CaO-CMC-Dcar nanoparticles exhibited enhanced antioxidant activity (80 %) compared to CaO (70 %) at 20 ?g/mL, with performance comparable to that of Vitamin C. Experimental results revealed that the CaO-CMC-Dcar nanoparticles exhibited superior biological activity compared to pure CaO nanoparticles. 2025 Indian Chemical Society -
Saraca asoca (Roxb.) de Wilde, a sacred tree: its nutritional value, elemental composition and anti-nutritional content
The sacred Saraca asoca (Roxb.) de Wilde tree holds significant medicinal value and is utilized in ayurvedic preparations to treat various health conditions. This research investigated the nutritional, elemental and antinutritional properties of S. asoca leaves and flowers. The nutritional qualities of the tree parts were examined using the muffle furnace and micro-Kjeldahl techniques. Titration techniques were used to assess the antinutritional content of plants, whereas EDX (Energy dispersive X-ray) was used to determine the mineral content. Phytochemical analysis revealed the presence of tannins, phenols and flavonoids, along with antioxidant properties that could neutralize free radicals generated by metabolic processes in the body. Nutritional analysis indicated that the floral parts of S. asoca had higher moisture, carbohydrate and crude fat content than the leaves. Conversely, the leaves had elevated ash levels, crude fiber and protein. Leaf samples showed higher concentrations of minerals like calcium, phosphorus, sodium, iodine, iron and manganese compared to the floral samples. In contrast, flower samples exhibited higher potassium, copper, silicon and zinc levels. These findings highlight the rich nutritional profile, abundant phytochemicals and essential minerals in both tree parts, with low anti-nutrient content. This information could be instrumental in developing phytopharmaceuticals and nutritious food products. Additionally, utilizing these tree parts could offer a cost-effective way to enhance nutrient intake and address nutritional deficiencies in humans and animals. Copyright: The Author(s). -
Exploring the dream pattern among the nightshift workers: A qualitative study
Nightshift workers are increasing day by day, but many times, people forget the health and sleep effects caused by the nightshift. One such impact is the altered circadian rhythm, which is very important for proper functioning of the body and a good sleep. This altered circadian rhythm can have an impact on waking and sleep life of the nightshift workers. This qualitative study is to find the dream pattern among the nightshift workers and to find the frequency in dreaming among this group. Dreams are the reflections of the waking life and dream patterns are seen among groups sharing similar wake life experiences. This study is conducted with nine nightshift and nine dayshift workers, dream journal was used to collect the dreams from the participants. The frequency of dreaming is seen more among the nightshift workers. The dream patterns among both the groups are similar but there are dreams that make the nightshift group different from the dayshift. The dreams of the nightshift group includes mainly their friends and the feelings of being stuck/in danger. Also, their dreams were more fantastic in nature and have more emotional content. The study shows that sexual dreams are seen majorly among the nightshift group. This finding can be further used to conduct researches on the impact of nightshift on the sexual health and overall well being of nightshift workers and the reflection of the same in their dreams. 2020. All Rights Reserved. -
Patent Dispute settlement through Arbitration and the public policy concerns
India is a developing nation, which had shown both progress and decline in economy over the years. Intellectual property rights are considered as an important asset of a nation. National legislations are made in par with the international conventions and treaties, more concentration on the industry and investments are needed for the development of the nation. Patent legislations changed on basis of the national and international needs. The monopoly right granted for an invention is on the basis of their intellectual skill. Patent dispute settlement mechanisms are mainly patent office through controller of patent, District Court & High Court and the patent tribunals. Patent is granted for 20years in India. The patent holder can utilize the same within this short span of time. Hence all the patent holders and the public challenging the validity of the patent, expect a speedy justice in patent disputes. This research paper addresses the question as to whether subject matters that can be referred for arbitration can be limited on grounds of public policy. Further the paper will address the issues as to whether arbitration can be effective mechanism for settling patent disputes in India. 2023 Brazilian Center for Mediation and Arbitration - CBMA. All Rights Reserved. -
Biological extraction of chitin from fish scale waste using proteolytic bacteria Stenotrophomonas koreensis and its possible application as an active packaging material
Chitin being the second most abundant polymer found in nature has extensive application and versatile material properties including biocompatibility. Extraction of chitin from diverse sources are majorly done using chemical extraction methods using high concentration of alkali that makes the method non eco-friendly and economically non-viable. This calls for eco-friendly methods of chitin extraction from cost-effective substrates through green methods. This research work presents a simplified one-step biological extraction of chitin from fish scales by successive fermentation using Stenotrophomonas koreensis isolated from soil. The fermentative approach for chitin extraction from fish scales using S. koreensis enzyme activity is not reported elsewhere in the available literature to the best of our knowledge. Chitin yield of 28% (w/w) was obtained after the successive fermentation. The extracted polymer was characterized using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and thermo gravimetric analysis (TGA). Furthermore, the possibility of converting extracted chitin into an active packaging material was explored by chemically, converting it to chitosan followed by analysis of its DPPH scavenging activity. The DPPH radical scavenging activity varied from 67.025 to 80.2%, which corresponds to 0.25 to 2mg/mL of chitosan. The chitosan films fabricated were subjected to biodegradation studies using soil burial method. Biodegradation rate of chitosan films was observed to be 21.49 0.62% (w/w) after 50days of incubation. Thus, the present research work highlights an integrated waste valorization strategy through microbial fermentation for commercially important biopolymer production. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. -
In vivo, in vitro and in silico screening of a potent Angiotensin Converting Enzyme (ACE) inhibitor from Trigonella foenum-graecum extract using Zebrafish as a model organism to reduce hypertension
The number of patients suffering from hypertension is on the rise worldwide and there is a need to explore natural products which can supplement current drugs to treat this disease. RAAS (Renin Angiotensin Aldosterone System) is one of the factors maintaining blood pressure. In the present investigation, we explored the potential of methanolic extract of fenugreek seeds in inhibiting Angiotensin Converting Enzyme (ACE), a key enzyme in the RAAS system, thereby reducing hypertension. In addition to in vivo studies conducted on zebrafish, in vitro and in silico studies were also performed to assess the inhibitory effect of the fenugreek extract on ACE. The bioactive components in Trigonella foenum-graecum revealed by GC-MS were further subjected to docking and binding studies with the receptor protein ACE. Of the various phytochemicals studied, arachidonic acid exhibited the maximum inhibitory effect on ACE. Thus, the present investigation was able to favorably screen a potent ACE inhibitor in Trigonella foenum-graecum extract which shows a potential to be used alone or supplemented with synthetic ACE inhibitors to treat high blood pressure. Further investigations are required to quantify the phytochemical for its inhibitory activity and also to understand the mechanism of inhibition of the enzyme. 2020 World Research Association. All rights reserved. -
Factors affecting intra-relations of backend cost drivers in multi-brand retail domestic super market under convenience stores format: A customer aligned model of supply-chain optimisation framework /
Asian Journal Of Management, Vol.8, Issue 1, pp.78-86, ISSN: 0976-495X (Print), 2321-5763 (Online). -
An Empirical Study on Gold ETF Volatility - Evidence From Indian Market
Zenith International Journal of Business Economics & Management Research, Vol-3 (7), pp. 223-232. ISSN-2249-8826 -
An Empirical Study on Stochastic Volatility - Evidence From Indian Commodity Future Market
Asian Journal of Research in Business Economics and Management, Vol-3 (8), pp. 39-46. ISSN-2249-7307 -
An Empirical Study on announcement effects of right issues on share price volatility and liquidity and its impact on market wealth creation of informed investors in Bangalore with special reference to CNX Nifty Stocks of NSE
Excel International Journal of Multidisciplinary Management Studies Vol. 2, No. 7, pp 41-58, ISSN No. 0972-687X -
An Empirical study on price pressure and liquidity effect of stock split announcement- Evidence from Indian Market
International Journal of Marketing and Technology Vol.3,No.1,pp.138-156 ISSN No. 2249-1058 -
Determinants of Book Built IPO underpricingdifferential issue size and market momentum approach revisited
Pricing of an Initial public offering (IPO) is a complex phenomenon. Price anomalies are commonly observed in IPO markets, especially in emerging markets. Investors perceived underpricing creates undue market momentum during the offer period with an asymmetric effect across different issue sizes. This study examines the determinants of Book Built IPOs underpricing by considering a sample of 180 Book Built IPOs that went public in India between 2011 and 2020. The determinants were verified for differential issue size public offers. Listing day performance was measured using Listing Day-Absolute Return (LD-AR) and Listing Day-Market Adjusted Return (LD-MAR) models. Further, the data obtained was tested for the explanatory capabilities of firm-specific and market momentum factors for underpricing using OLS models. Concerning the differential issue size, the study found a direct relationship between the issue size and underpricing. Dominant underpricing was observed in the case of moderate to large issue size with a linear progressive return, confirming that there was over-optimism on the part of investors. The studys results also revealed that momentum-specific factors have a significant influence along with firm-specific factors such as firm size, cash flows, a subscription rate of QIBs and RIIs in the listing day return, and underpricing. 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.