Comparative Study of Taguchi and Genetic Algorithm in Electric Discharge Machining Parameters on Titanium Alloy (Ti 6Al 4V)

The aim of this work is to research the have an effect on of manner parameters and determine the top of the line system parameters in electric discharge machining (EDM) of Titanium alloy (Ti 6Al 4V) .The parameters taken into consideration are peak modern, pulse on time and pulse off time in which as the responses are material removal rate (MRR) and surface Roughness (SR). MITSUBISHI EA8 spark erosion machine is hired for this paintings and copper tungsten electrode of ∅14 mm is utilized in experimental trials. The experimental trials are carried out based totally on Taguchi L27 orthogonal array with 3 levels of every machining parameters. The signal to noise ratio, the evaluation of variance (ANOVA), regression analysis and Genetic algorithm are hired to locate the highest quality stages and to analyze the consequences of machining parameters on metal elimination charge and floor roughness. Confirmation tests with the most beneficial levels of machining parameters are completed which will illustrate the effectiveness of Taguchi and Genetic set of rules optimization approach. Assessment of Taguchi’s and Genetic set of rules had been employed to analyze the effective top quality fee

Sarcomas of the scalp: a case series

Sarcomas of the scalp are a diverse group of rare and aggressive neoplasms of the head and neck originating from bony or soft tissue elements. Clinical manifestations of sarcomas of the scalp vary from small plaque-like lesions to multifocal nodules with involvement of deeper layers, and it is the extent and grade of the tumor that determines the treatment plan. Majority of the cases are managed surgically with three-dimensional wide excision and robust reconstruction. The role of adjuvant radiotherapy and chemotherapy is limited to those cases with poor prognosis. Very few cases of sarcomas involving the scalp have been reported in the literature. We wish to share a series of three rare mesenchymal tumors of the scalp, two of which were locally advanced at the time of presentation. This case series highlights the surgical management, options for reconstruction and outcomes of these tumors

A pre-specified analysis of the DAPA-CKD trial demonstrates the effects of dapagliflozin on major adverse kidney events in patients with IgA nephropathy

Immunoglobulin A (IgA) nephropathy is a common form of glomerulonephritis, which despite use of renin-angiotensin-aldosterone-system blockers and immunosuppressants, often progresses to kidney failure. In the Dapagliflozin and Prevention of Adverse Outcomes in Chronic Kidney Disease trial, dapagliflozin reduced the risk of kidney failure and prolonged survival in participants with chronic kidney disease with and without type 2 diabetes, including those with IgA nephropathy. Participants with estimated glomerular filtration rate (eGFR) 25-75 mL/min/1.73m2 and urinary albumin-to-creatinine ratio 200-5000 mg/g (22.6-565 mg/mol) were randomized to dapagliflozin 10mg or placebo, as adjunct to standard care. The primary composite endpoint was a sustained decline in eGFR of 50% or more, end-stage kidney disease, or death from a kidney disease-related or cardiovascular cause. Of 270 participants with IgA nephropathy (254 [94%] confirmed by previous biopsy), 137 were randomized to dapagliflozin and 133 to placebo, and followed for median 2.1 years. Overall, mean age was 51.2 years; mean eGFR, 43.8 mL/min/1.73m2; and median urinary albumin-to-creatinine ratio, 900 mg/g. The primary outcome occurred in six (4%) participants on dapagliflozin and 20 (15%) on placebo (hazard ratio, 0.29; 95% confidence interval, 0.12, 0.73). Mean rates of eGFR decline with dapagliflozin and placebo were −3.5 and −4.7 mL/min/1.73m2/year, respectively. Dapagliflozin reduced the urinary albumin-to-creatinine ratio by 26% relative to placebo. Adverse events leading to study drug discontinuation were similar with dapagliflozin and placebo. There were fewer serious adverse events with dapagliflozin, and no new safety findings in this population. Thus, in participants with IgA nephropathy, dapagliflozin reduced the risk of chronic kidney disease progression with a favorable safety profile

Dry Sliding-Friction and Wear Behavior of Hot-Extruded Al6061/Si3N4/Cf Hybrid Metal Matrix Composite.

The effects of reinforcement addition and hot extrusion on the microstructures, micro hardness, friction, and wear behavior of aluminium (Al) hybrid composite were investigated. Al6061 dispersed with electroless nickel-coated Si3N4 (6wt.%) and copper-coated carbon fiber (Cf) (1wt.%) hybrid composites was developed through stir casting followed by hot extrusion. Optical micro structural studies confirmed that the size of reinforcements decreased, and their orientations were in the extrusion direction. The decrease in the grain size (29%) of hybrid composites was larger than that in the grain size of matrix alloys under hot-extruded conditions. The synthesized hot-extruded Al6061 hybrid composite exhibited a lower coefficient of friction (51%) and high wear resistance (39%) compared with the hotextruded Al6061base alloy

Optimization of electric discharge machining parameters on titanium alloy (ti-6al-4v) using Taguchi parametric design and genetic algorithm

The aim of this research work is to analyze the significant of process variables and find the optimum process variables in electric discharge machining (EDM) of Titanium alloy (Ti-6Al-4V) .The variables considered are peak current, pulse-on-time and pulse-off-time where as the responses are Material Removal Rate(MRR) and Surface Roughness(SR). MITSUBISHI EA8 spark erosion machine is employed for this work and copper tungsten electrode of ∅14 mm is used in experimental trials. The experimental runs are done based on Taguchi L27 orthogonal array. The signal-to-noise ratio, the analysis of variance (ANOVA), regression analysis and Genetic algorithm are used to determine the optimal levels of machining parameters on Metal removal rate and Surface roughness. Confirmation tests also done with the optimal levels of machining variables. Comparison of Taguchi’s and Genetic algorithm were employed to analyze the effective optimum value

Dry Sliding Wear Behaviour of AA6061-T6 Reinforced SiC and Al2O3 Particulate Hybrid Composites

AbstractDry wear behaviour of AA6061 Aluminum alloy, reinforcement with fine particulates of Silicon Carbide (25μm) and Aluminium oxide(40μm) are existed and discussed here in research paper. The reinforcement of Al alloy hybrid metal matrix composite (HMMCs) with 5-25% vol. fractions of Silicon Carbide and Aluminium oxide particles are produced by stir casting methodology and test specimen were prepared by using them. The dry sliding behaviour of these hybrid metal matrix composite specimen and that of Al6061 unreinforced alloy at ambient temperature was examined by using pin-on-disk Wear Testing Machine over a weight range of 29.43N-49.05N (3-5 kgf) along a sliding distance of 1413m at constant sliding speed of 1.57m/s. The result confirms that, the reinforced metal matrix with Silicon Carbide and Aluminium oxide particles up to a vol. fraction of 25% reduces the wear in μm at ambient temperature. Increases the volume fraction of the reinforcement decreases the wear in μm. The result also displays that the wear in μm of test specimen increase with increase in load and sliding distance