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The traditional Taguchi method is widely used for optimizing the process parameters of a single response problem. Optimization of a single response results the non-optimum values for remaining. But, the performance of the manufactured products is often evaluated by several quality characteristics/responses. Under such circumstances, multi-characteristics response optimization may be the solution to optimize multi-responses simultaneously. In the present work, a multi-characteristics response optimization model based on Taguchi and Utility concept is used to optimize process parameters, such as speed, feed, depth of cut, and nose radius on multiple performance characteristics, namely, surface roughness (Ra) and material removal rate (MRR) during turning of AISI 202 austenitic stainless steel using a CVD coated cemented carbide tool. Taguchi's L8 orthogonal array (OA) is selected for experimental planning. The experimental result analysis showed that the combination of higher levels of cutting speed, depth of cut, and nose radius and lower level of feed is essential to achieve simultaneous maximization of material removal rate and minimization of surface roughness. The ANOVA and F-tests are used to analyze the results. Further, the confirmation tests are conducted and the results are found to be within the confidence interval.

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The effects of moderate and severe degrees of iron deficiency on brain and liver nonhaem iron levels and 5-hydroxytryptamine (serotonin; 5-HT) uptake by synaptic vesicles in vitro were investigated in experimental rats. Data obtained suggested that in both moderate and severe forms of iron deficiency, 5-HT uptake by brain synaptic vesicles is decreased and is accompanied by a reduction in brain and liver nonhaem iron levels. On repletion with iron for 4 weeks, the deficient group of rats showed a normalisation of 5-HT uptake by synaptic vesicles and liver nonhaem iron content, whereas the brain nonhaem iron concentration still showed a significant deficit. The data thus suggest that changes in the uptake of 5-HT by brain synaptic vesicles that accompany iron depletion and repletion are more rapid than changes in the total nonhaem iron concentration in the brain. The observation that 5-HT uptake by brain synaptic vesicles is decreased in iron deficiency suggests a probable role for iron in 5-HT storage in rat brain.

In this work, Taguchi method is applied to determine the optimum process parameters for turning of AISI 304 austenitic stainless steel on CNC lathe. A Chemical vapour deposition (CVD) coated cemented carbide cutting insert is used which is produced by Duratomic TM technology of 0.4 and 0.8 mm nose radii. The tests are conducted at four levels of Cutting speed, feed and depth of cut. The influence of these parameters are investigated on the surface roughness and material removal rate (MRR). The Analysis Of Variance (ANOVA) is also used to analyze the influence of cutting parameters during machining. The results revealed that cutting speed significantly (46.05%) affected the machined surface roughness values followed by nose radius (23.7%). The influence of the depth of cut (61.31%) in affecting material removal rate (MRR) is significantly large. The cutting speed (20.40%) is the next significant factor. Optimal range and optimal level of parameters are also predicted for responses.

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Austenitic stainless steels are a widely used group of stainless steels. Problems have been reported by users during machining due to its low thermal conductivity, high work hardening, high strength, and high ductility. These made it difficult to machine the materials. The aim of the present study is to investigate the influence of Pressure Vapour Deposition (PVD) and Chemical Vapour Deposition (CVD) coated cemented carbide inserts on the surface quality of the work piece when turning on AISI 304 austenitic stainless steel work pieces, on computer numerical controlled (CNC) lathe. Taguchi's Design of Experiments approach (DOE) is used to analyze the effect of process parameters on surface roughness to obtain their optimal setting. The analysis of variance (ANOVA) is employed to analyze the influence of process parameters during turning. The results have shown that the improvement in average surface finish is obtained when machining with PVD coated insert (1.13 µm).The nose radius is the most significant process parameter (62.88% contribution) when turning with PVD insert. The cutting speed is the most significant factor (37.84% contribution) when turning with CVD insert. Optimal ranges of surface roughness values are also predicted.