Journal of Science & Technology (JST)
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Simulation of Multilevel Inverter Fed Induction Motor Drive
Get PDFThe ruggedness, dependability, and economy of induction motors make them a popular choice in the industrial sector. Induction motor drive necessitates the use of appropriate converters in order to achieve the required speed and torque with minimal or no ripples. Multilevel inverter technology has recently emerged as a very important alternative in the areas of high power medium-voltage control as well as for improving total harmonic distortion by reducing the harmonics, both of which are important considerations. Most of the time, the poor quality of voltage and current produced by a conventional inverter fed induction machine is due to the presence of harmonics, which results in a significant amount of energy being wasted. In MATLAB, the simulation results of the proposed topology three phase 33-level multilevel inverter fed induction motor drive are verified against the real-world results
“Evaluation of in vitro antioxidant and free radical scavenging activity of leaf and twig endophytic fungal extract from Mappia foetida”
Get PDFThe present study was aimed to investigate the in vitro free radical scavenging activity of leaf extracts. In vitro free radical scavenging activities of the endophytic extracts were assessed against DPPH and hydroxylradicals. The metal chelating activity and reducing power ability of the extracts of M. foetida. were also determined. The free radical scavenging activity was found to be high in methanolic extract for DPPH and hydroxyl radicals. The difference in scavenging potential of the endophytic extracts may be due to variation in the percentage of phytoconstituents extracted in methanolic solvents. Thus, the result suggests that the methanolic leaf extract of M. foetida could serve as a potential source of antioxidants and can be explored as a therapeutic agent in free radical induced diseases.
 
A Strategic Approach for 2D Texture Analysis using DTCWT, SWT and GLCM
Get PDFNowadays, 2D imaging techniques have gone through several stages of development in 2D sensor technologies. This probes greater interest in the 2D image feature extraction and classification techniques. One of the
main features of 2D image are texture content which is very enthusiastic to study. The proposed strategy is to extract
and analyse of texture content of 2D image. In this strategy Dual Tree Complex Wavelet Transform (DTCWT) and Stationary Wavelet Transform (SWT) with Principal Component Analysis (PCA) is implemented to extract the features of the 2D images especially texture content for further analysis. The texture content is analysed with Gray-Level Co- Occurrence Matrix (GLCM) based method which increase the precision of the data obtained which causes better result.
 
Characterisation of Waste plastic oil by Fourier Transform Infrared Spectroscopy and Gas Chromatography-Mass Spectrometry
Get PDFPlastics is an essential part in today’s world due to their lightweight, enduringness, faster rate of production and design flexibility. At the corresponding time, waste plastics have created very real environmental challenges due to their immense quantities and disposal problems. Pyrolysis process is an advisable method for converting waste plastics into waste plastic oil (WPO) because of their advantages such as high conversion output, independent feedstock, low pressure operation and least amount of waste produced. GC-MS of WPO contains longer hydrocarbon chains which depicts the burning quality of fuel. No formation of highly toxic poly aromatic hydrocarbon chains was found, such as carcinogens, mutagens and teratogens in the WPO. FTIR spectrum of WPO, the presence of alkenes and alkanes is detected at 3074.59 cm-1 & 2890.59 cm-1 with simple C-H stretching vibrations. The existence of ketones is noticed at 1713.78 cm-1 with C=O stretching vibrations. C=C stretching vibrations at 1652.06 cm-1 indicates the existence of alkenes. The components present in the waste plastic oil are mostly, the aliphatic hydrocarbons (alkanes and alkenes) with carbon number C10 - C25.
 
Postbiotics; Novel Ingredient in Functional Foods
Get PDFPostbiotics defined as “non-viable bacterial products or metabolic products from microorganisms that have biological activity in the host”. Postbiotics are the different mixture of healthy metabolic products or secreted components of probiotics in cell-free supernatants such as enzymes, secreted proteins, short chain fatty acids, vitamins, amino acids, peptides, organic acids, etc. The functional foods can be defined as “any food that has a positive impact on an individual’s health, physical activities, or mental health, in addition to its nutritious value”. Also, it should help in regulate a particular body process, such as enhancement of biological defence mechanisms, prevention of specific diseases, control of physical and mental disorders, and decreasing the aging process. Postbiotics, are bacterial components or metabolites,they provide advantages and can mimic probiotics' favourable therapeutic effects. They accomplish this without exposing the body to live microbes. Their metabolic, immunological modulatory, antiobesity, anticancer, and antioxidant properties have all been help in cure more drastic disease. Not only have postbiotics been searched in vitro and in vivo, but they've also been used in the food industry. They are known to have a longer shelf life than other biotics, as well as easier storage, handling, and transportation. postbiotics helps in avoiding the risk of live microorganisms to the body. Postbiotics can be a good alternative as a treatment for human patients; thus, opening the way to the development of new pharmacological or food products with specific physiological effects
Mechanical Building Facilities :Maintenance of HVAC
Get PDFEvery nation desires and aspires to have sustainability in all spheres of development. This can be achieved through the provision of adequate maintenance of the acquired facilities. The article centers on HVAC system, description and maintenance strategies and practices in the system. The article is crafted with no specific case study. The paper discusses HVAC Systems, the test and maintenance essential equipment. Factors affecting the performance sufficiency of HVAC have been stated and step-by-step remedial action have also been itemized
EFFECT OF BRICK DUST ON SOME PROPERTIES OF CONCRETE
Get PDFIn today's world, concrete is the most durable and widely utilized construction material. Efforts have been made to boost some unique features of concrete by adding pozzolanic elements to improve its strength characteristics and other properties for different uses. Some of the materials have been effectively used to improve concrete's fresh properties, such as consistency, workability, bleeding and settlement, plastic shrinkage, and so on, as well as its hardened properties, such as durability, strength, density, porosity, thermal and acoustic insulation, impact resistance, and so on. As a result of increased demand, natural assets have become exceedingly expensive as building materials, raising the project's overall cost. Efforts are being made to incorporate waste components into concrete, which are environmentally detrimental, readily available, and reduce the project's overall cost. The use of these waste elements in concrete reduces waste in the environment while also lowering the overall cost of structures without compromising concrete quality.Brick dust can be replaced with cement up to a certain proportion without compromising the concrete's qualities. The goal of this research is to see if brick dust may be used as a cement substitute in concrete production. In varying quantities, brick dust was used in place of cement in concrete. The performance of concrete containing brick dust was compared to the control samples developed for this investigation. In all concrete samples, the water-cement ratio was standardized at 0.65.To fulfill the study's goal, brick dust was crushed and added to the concrete mixture to substitute cement in varying proportions of 0%, 5%, 10%, and 15%. Workability and compressive strength testing were carried out in the laboratory for 7, 14, and 28 days. The results show that a 10% replacement proportion of brick dust in concrete over 28 days of curing enhanced the compressive strength of the concrete when compared to control specimens and laboratory testing. The workability of the concrete increases with the addition of brick dust to the mix. As a result, it has been established that substituting brick dust in the concrete production process is suitable
NATION BRANDING- A CASE STUDY OF THE SULTANATE OF OMAN
Get PDFIncreasingly, countries with emerging economies are focusing on building their national identities. In an increasingly interconnected globe, many countries—including several in the Middle East—are looking for ways to strengthen and diversify their economies. The article defines the concepts of national branding, place marketing, and destination marketing, and specifies the aspects of national branding while highlighting Oman's efforts to develop brand Oman. The Middle Eastern country of Oman, which is home to vast oil reserves, has launched a massive tourist promotion campaign. The Ministry of Tourism has planned a number of domestic and international initiatives to combat the country's regional rivals. Even though there is a lot of land to cover, the results have not yet been documented but the view for the future is optimistic
Application of Ground Granulated Blast Furnace Slag (GGBS) In High Performance Concrete
Get PDFApplication of Ground Granulated Blast Furnace Slag (GGBS) for high-performance concrete is the demand of the decade as a supplementary cementitious material for making concrete more environmentally friendly and economical. In this research, the properties of High-performance concrete have been evaluated by incorporating (GGBS) as a replacement for cement, the production of which increases the amount of CO2 generated in the environment. This research focuses on making an M70 grade concrete mix with minimum use of cement and increasing the potential application of GGBS in various percentages. The properties evaluated during the experimental study were compressive strength, flexural strength, and split tensile strength of concrete. The result of the study concludes that the GGBS as a mineral admixture helps to control the quality of concrete and the workability of the mix is also increased. The result of the study also showed positive insights. The maximum compressive strength achieved with the use of mineral admixture is 77.4 Mpa and maximum tensile strength is 5.1 Mpa and flexural strength after 28 days of testing is 9.1 Mpa
Coverage Strategies for Wireless SensorNetworks
Get PDFCoverage is one of the main research interests in wireless sensor networks (WSN), it is used to determine the quality of service (QoS) of the networks. Therefore this paper aims to review the common strategies use in solving coverage problem in WSN. The strategies studied are used during deployment phase where the coverage is calculated based on the placement of the sensors on the region of interest (ROI). The strategies reviewed are categorized into three groups based on the approaches used, namely; force based, grid based or computational geometry based approach