RISK MAINTENANCE STRATEGY IN BLADE MANUFACTURING INDUSTRY MACHINERIES - BY USING APPLICATIONS OF TOPSIS METHOD

Regarding the capital and operating expenses of windmill turbines, blades are amongst the most vital parts. Those blades are made using conventional manufacturing methods such as deep groove machine, CNC Machine, foam slicing machine, glass layer machine, glass layer winding machine, balsa angle cutting machine, etc. In this research, TOPSIS (Technique for Order Performance by Similarity to Ideal Solution) method is used to sort the machining methods that need to be handled very carefully according to risk and hazard in blade production. This research objective is to find the windmill blade design data, various production processes and its hazards, risks etc. with the help of previous research papers. Through these results, using the TOPSIS method, a priority number can be given to all the production processes and the safety windmill blade production processes that need more attention can be identified

COMPARATIVE IN-VITRO ANTIBACTERIAL AND ANTIFUNGAL ATTRIBUTES OF DIFFERENT SOLVENT EXTRACTS FROM LEAF, BARK, ROOT AND INFLORESCENCE OF MEMECYLON UMBELLATUM BURM.

This paper describes the antibacterial and antifungal activities and Minimum Inhibitory Concentration (MIC) of different solvent (pet. ether, chloroform, ethyl acetate, acetone, methanol and water) extracts of leaves, bark, root and inflorescence of Memecylon umbellatum burm. The percent yields from leaves, bark, root and inflorescence was found to be 0.2062 to 2.836, 0.0601 to 0.5142, 0.050 to 1.425, 0.0210 to 0.717 respectively. Overall, acetone extract produced from the leaves exhibited significantly (P < 0.05) higher antibacterial activity along with superior antifungal activity. MIC for acetone and ethyl acetate extract of leaf was found to be 0.5 mg for the entire organisms compared to 3-15 mg for other extracts. Such study will explore pharmacological activity of the tested parts of Memecylon umbellatum burm especially, the leaves which might be valuable for therapeutic applications

Enhanced fluorescent properties of an OmpT site deleted mutant of Green Fluorescent Protein

<p>Abstract</p> <p>Background</p> <p>The green fluorescent protein has revolutionized many areas of cell biology and biotechnology since it is widely used in determining gene expression and for localization of protein expression. Expression of recombinant GFP in <it>E. coli </it>K12 host from pBAD24M-GFP construct upon arabinose induction was significantly lower than that seen in <it>E. coli </it>B cells with higher expression at 30°C as compared to 37°C in <it>E. coli </it>K12 hosts. Since OmpT levels are higher at 37°C than at 30°C, it prompted us to modify the OmpT proteolytic sites of GFP and examine such an effect on GFP expression and fluorescence. Upon modification of one of the two putative OmpT cleavage sites of GFP, we observed several folds enhanced fluorescence of GFP as compared to unmodified GFPuv (Wild Type-WT). The western blot studies of the WT and the SDM II GFP mutant using anti-GFP antibody showed prominent degradation of GFP with negligible degradation in case of SDM II GFP mutant while no such degradation of GFP was seen for both the clones when expressed in BL21 cells. The SDM II GFP mutant also showed enhanced GFP fluorescence in other <it>E. coli </it>K12 OmpT hosts like <it>E. coli </it>JM109 and LE 392 in comparison to WT GFPuv. Inclusion of an OmpT inhibitor, like zinc with WT GFP lysate expressed from an <it>E. coli </it>K12 host was found to reduce degradation of GFP fluorescence by two fold.</p> <p>Results</p> <p>We describe the construction of two GFP variants with modified putative OmpT proteolytic sites by site directed mutagenesis (SDM). Such modified genes upon arabinose induction exhibited varied degrees of GFP fluorescence. While the mutation of K79G/R80A (SDM I) resulted in dramatic loss of fluorescence activity, the modification of K214A/R215A (SDM II) resulted in four fold enhanced fluorescence of GFP.</p> <p>Conclusions</p> <p>This is the first report on effect of OmpT protease site modification on GFP fluorescence. The wild type and the GFP variants showed similar growth profile in bioreactor studies with similar amounts of recombinant GFP expressed in the soluble fraction of the cell. Our observations on higher levels of fluorescence of SDM II GFP mutant over native GFPuv in an OmpT⁺host like DH5α, JM109 and LE392 at 37°C reiterates the role played by host OmpT in determining differences in fluorescent property of the expressed GFP. Both the WT GFP and the SDM II GFP plasmids in <it>E. coli </it>BL21 cells showed similar expression levels and similar GFP fluorescent activity at 37°C. This result substantiates our hypothesis that OmpT protease could be a possible factor responsible for reducing the expression of GFP at 37°C for WT GFP clone in K12 hosts like DH5α, JM109, LE 392 since the levels of GFP expression of SDM II clone in such cells at 37°C is higher than that seen with WT GFP clone at the same temperature.</p

Numerical simulation of heat sinks with different configurations for high power LED thermal management

This study performed a steady-state numerical analysis to understand the temperature in different heat sink configurations for LED applications. Seven heat sink configurations named R, H-6, H-8, H-10, C, C3, and C3E3 were considered. Parameters like input power, number of fins, heat sink configuration were varied, and their influence on LED temperature distribution, heat sink thermal resistance and thermal interface material temperature were studied. The results showed that the temperature distribution of the H-6 heat sink decreased by 46.30% compared with the Cheat sink for an input power of 16 W. The result of the H-6 heat sink shows that the heat sink thermal resistance was decreased by 73.91% compared with the Cheat sink at 16 W. The lowest interface material temperature of 54.11 °C was achieved by the H-6 heat sink when the input power was used 16 W. The H-6 heat sink exhibited better performance due to more surface area with several fins than other heat sinks.https://www.ijsmdo.orghj2023Mechanical and Aeronautical Engineerin

Phytochemical screening and In Vitro Antioxidant potential of Memecylon umbellatum Burm leaf extracts

Objective: Different dry extracts of Memecylon umbellatum Burm leaf obtained by various solvents such as petroleum ether, chloroform, ethyl acetate, acetone, methanol and chloroform water (IP) was screened to reap the benefits of its antioxidant and free radical scavenging properties using ascorbic acid as standard antioxidants. Methods: The in vitro free radical scavenging activity was evaluated using diphenyl picryl hydrazyl (DPPH) radical method using various concentrations of dry extract in distilled water (1, 2, 4, 8, 16, 20 μg/ml) against blank with ascorbic acid as a standard in same concentrations. Results: Among the all extracts, Methanol leaf extract has showed higher Antioxidant activity (84.65 ± 0.064 %) having IC50 Value 11.81 ± 0.033 μg/ml at 20 μg/ml. While, IC50 value for ascorbic acid was found to be 8.91 ± 0.084 μg/ml. Conclusion: The results clearly indicate that Methanol leaf extract of Memecylon umbellatum is effective in free radical scavenging. So in future, this may emerge as promising natural herbal source of powerful antioxidant. Keywords: Memecylon umbellatum, DPPH reagent, Antioxidant activity, Ascorbic acid, IC50

Experimental study on the effect of in/out radial-finned heat sink with PCM under constant and intermittent power mode in power LEDs

DATA AVAILABILITY : All data that support the findings of this study are included within this article.The findings of the experimental study into optimizing the heat transfer rate of a PCM-based heat sink for high-power LEDs are presented in this work. The study investigated five heat sink types, with and without PCM. The LED case and junction temperatures, LED module temperatures, heat storage and release rate analyses, analyses of three types of cyclic operation modes, luminous flux, and heat sink thermal resistance were all examined independently. The results indicated that the PCMbased LED heat sink had improved thermal performance. The LED junction temperature of the PCM-equipped E-20 heat sink is nine degrees Celsius lower at 10W than that of the heat sink without PCM. Furthermore, the E-20 heat sink with PCM extends the LED module’s critical lifespan. As a bonus, the E-20 with PCM had a 38.19 percent lower thermal resistance at 10W than the E-20 without PCM. According to these results, the heat sink E-20 emits 715 lm at 10W when operated without a phase-change material (PCM). With the same input power, the luminous flux of an E-20 equipped with a heat sink and a phase-change material (PCM) is 750 lm, a gain of 4.7%. Finally, clearly recommend the heat E-20 sink with PCM suitable for high-power LED thermal management system.King Saud University.https://onlinelibrary.wiley.com/journal/3837am2024Mechanical and Aeronautical EngineeringSDG-09: Industry, innovation and infrastructur

Parametric optimization of wear parameters of hybrid composites (LM6/B4C/fly ash) using Taguchi technique

Wear is prominent in sliding components, so tribology property plays a major role in automotive as well as in the aerospace industries. In this work, Aluminium alloy LM6/B4C/Fly Ash hybrid composites with three different weight percentages of reinforcement were fabricated using the low-cost stir casting technique, and the experiments were conducted based on the Design of Experiments (DoE) approach and optimized using Taguchi’s Signal to noise ratio (S/N) analysis. The analysis was conducted with process parameters like Sliding Speed (S), Sliding distance (D), load (L) and reinforcement percentage (R %), the responses are Coefficient of Friction (COF) and Specific wear rate (SWR). Aluminum alloy reinforced with 9 wt% hybrid (LM6 + 4.5% B4C + 4.5% Fly Ash) has a low density and high hardness compared with other composites and base alloys. The optimum parameters for obtaining minimum SWR are S - 1 m/s, D - 500 m, L - 45 N, and R% - 6 wt% Hybrid (3% Fly ash and 3% boron carbide). The optimum parameters for obtaining minimum COF are S - 1.5 m/s, D - 500 m, L - 30 N, and R% −9 wt% Hybrid (4.5% Fly ash and 4.5% boron carbide). Load (28.34%) is the most significant parameter for obtaining minimum SWR, and DL (31.62%) for obtaining minimum COF. SEM images of the worn pins show the various wear mechanisms of the AMCs. The hybrid composite produced is new and these may be used for piston liner and brake pad applications

Analysis of the thickness of layered armor to provide protection against 7.62 mm ball projectiles using experimental and numerical methods

The layered configuration of different material plates is one of the ways of achieving protection against different kinds of kinetic energy ammunitions. The thickness of each plate is one of the most important influencing parameters to prevent the penetration of the projectile. In the present study, a layered configuration of the Al2O3 and Al 7075-T651 is analysed, to prevent the perforation of 7.62 mm Lead core projectile, under normal impact conditions, by using LS-DYNA numerical simulations. Experiments were conducted on Al 7075-T651 plate and Numerical model was validated with experiment results. To achieve the objective, the validated numerical model was used to investigate influence on various Al2O3 and Al 7075-T651 combinations. Three factors led to the selection of Al 7075-T561 and Al2O3 as the target materials. First, the literature review revealed that these materials have already been employed in the construction of armour. Second, Al2O3 is a brittle material whereas Al 7075-T651 is ductile. Consequently, when combined in a layered arrangement, these materials offer the ideal destroyer-absorber arrangement. Thirdly, these materials have lower densities than steel. As a result, these materials offer a lightweight alternative for lead core 7.62 mm bullet defense. From the analysis, it is observed that two layered configurations were found to be effective in the prevention of bullet perforation: a front plate of Al2O3 that was 10 mm thick and had a rear plate of Al 7075-T651 that was 06 mm thick, and a front plate of Al2O3 that was 04 mm thick and had a 12 mm thick layer of Al 7075-T651

Topology optimization of engine bracket arm using BESO

An engine bracket is one of the most critical components of the engine used for mounting and supporting the engine in the vehicles. Today, the automobile industry requires lightweight components, which will reduce the car's overall weight when fitted into the vehicle. Topology optimization is a technique with the help of which the surface of a component is optimized to get the required shape for having reduced weight. The weight is reduced by optimizing the material on the surface of the details. In this paper, the work done is the application of topology optimization on the surface of the engine bracket arm. Then the optimized model is tested computationally using realistic conditions. Bi-directional evolutionary structural optimization is used as a technique for topology optimization. With the help of the BESO method, the material optimization is done, and then the weights are compared with the original component. A new algorithm is developed using MATLAB codes. The sensitivity ratio is considered using the von Mises strength as a critical parameter for the BESO method for optimization. The optimized bracket model is then assembled with the hub of the component, and then the assembly is simulated for verification using standard conditions. A comparison of weight reduction is there using topology optimization