Pareto Analysis Of Variance Research Articles

Parametric Investigation of Leading-Edge Slats on a Blended-Wing-Body UAV Using the Taguchi Method

The current study investigated the effect of leading-edge slats on the longitudinal stability at high angles of attack of a Blended-Wing-Body (BWB) Unmanned Air Vehicle (UAV). Using a Design of Experiments (DOE) approach and, specifically, the Taguchi method, four leading-edge slat design parameters were investigated on three different levels. These parameters were the slat semi-span, the rotation of the slat element, the extension forward of the leading edge and the downward drop below the leading edge. An L9 orthogonal array (OA) was used to investigate the influence of these key design parameters using three performance criteria, namely the angle at which pitch break occurs, the corresponding speed and the distance between the Neutral point of each configuration and the Neutral point of the reference platform. The investigation was conducted by using high-fidelity Computational Fluid Dynamics (CFD) methods for each of the nine configurations defined by the L9 OA, over a range of angles of attack between −4 and 16 degrees. Based on these results, and using a Signal-to-Noise ratio (SNR) analysis, two combinations were eventually derived, one that optimized pitch break angle and speed and one that optimized longitudinal stability. Finally, the Pareto Analysis of Variance (ANOVA) technique was conducted to define the contribution of each of the six design parameters on the selected performance criteria. More specifically, the semi-span seemed to have the most significant effect on pitch break angle and speed, whereas the rotation of the slat element was the most important parameter with regard to static stability.

Parametric Investigation of Canards on a Flying Wing UAV Using the Taguchi Method

The current work investigates the effect of canard geometric characteristics on the performance of a lightweight flying wing Unmanned Aerial Vehicle (UAV), capable of both conventional and Vertical Take-Off and Landing (VTOL) flight. The canards are sized as horizontal stabilizers to enhance the UAV’s longitudinal stability and minimize trimming requirements during cruise. Using a Design of Experiments (DOE) approach and, specifically, the Taguchi method, six canards’ design parameters are investigated on three different levels. These parameters are the sweep angle (Λ), aspect ratio (AR), taper ratio (λ), vertical position in relation to the main wing (vpos), incidence angle (ic), and dihedral angle (Γ). An L27 orthogonal array (OA) is used to investigate the influence of these key design parameters using two performance criteria, namely the Lift-to-Drag ratio (L/D) and the pitching moment coefficient (Cm), at cruise conditions (designated as L/Dcruise and |Cm|cruise). The investigation is conducted by using high-fidelity Computational Fluid Dynamics (CFD) methods for each of the 27 configurations defined by the L27 OA, over a range of angles of attack. Based on the CFD results, two distinct combinations are derived for maximum L/Dcruise and minimum |Cm|cruise using the Signal-to-Noise ratio (SNR) analysis. The optimal design parameter combinations for the two performance criteria are A2B1C1D1E1F1 and A2B2C1D2E2F3, respectively. Finally, the Pareto Analysis of Variance (ANOVA) technique is conducted to define the contribution of each of the six design parameters on the L/Dcruise and the |Cm|cruise. More specifically, ic seems to have the most significant effect on L/Dcruise, whereas Λ is the most important parameter for |Cm|cruise.

Enhancement of PVA packaging properties using calcined eggshell waste as filler and nanonutrient

With an understanding of the disadvantages of petroleum-based polymers and the need for biodegradable polymers and nanofillers to overcome the problems of natural polymers, we repurpose the waste materials as nanofiller for PVA polymer. Eggshell, an excess component in kitchen waste, can be calcined to calcium oxide that was used as a binder to enhance the PVA stability and physical and chemical properties. Application of calcium oxide was not only for strength improvements, but also to supply nutrients to the soil after degradation. The water-resistance property and degradation ability of films were studied completely by varying the PVA composition and CaO concentration. In addition to the degradation study, the influence of solubilised polymer solutions given to soil and their influence on plant growth were analysed. The impact of parameter variation (PVA, CaO, and glycerol) on the film properties like thickness (THI), water solubility (SOL), moisture content (MC), water absorption, water vapour transmission rate (WVTR), tensile strength (TS) and elongation (ELONG) was investigated using a three-level Box–Behnken response surface design, Pareto analysis of variance (ANOVA), and a second-order polynomial model. Three-dimensional response surface plots were generated to investigate the relationship between process variables and the responses.

Optimization of the Anaerobic-Anoxic-Oxic Process by Integrating ASM2d with Pareto Analysis of Variance and Response Surface Methodology

Wastewater treatment plants (WWTPs) are high-energy-consuming units. Reasonable operation strategies can enable WWTPs to meet discharge standards while reducing the operating cost. In this study, the activated sludge model 2d (ASM2d), Pareto analysis of variance (ANOVA), and response surface methodology (RSM) were jointly used to simulate and optimize the operation of a lab-scale anaerobic-anoxic-oxic (AAO) reactor. The optimization objective was to determine the optimal design and operational parameters (DOPs) that could enhance both pollutant removal and energy saving. The DOPs that had significant influence on the optimization objective, such as sludge retention time (SRT), dissolved oxygen (DO), and the ratio of biodegradable chemical oxygen demand to total nitrogen (BCOD/TN), were identified by Pareto ANOVA. The optimal DOPs with SRT of 15 days, DO concentration of 0.5 mg/L, and BCOD/TN of 5.21 were determined by RSM. Under the optimal conditions, the removal efficiencies of NH4+-N, total nitrogen (TN), and total phosphorus (TP) were 96.2%, 76.8%, and 92.8%, respectively, and the annual operating cost was $26.4. Furthermore, this combination of DOPs was validated using a pilot-scale AAO system. The TN and TP removal efficiencies were improved by 11.0% and 5.0%, respectively, and the annual operating cost could be reduced by 15.0%. Overall, this study confirmed that the method integrating ASM2d with Pareto ANOVA and RSM was effective in optimizing wastewater treatment processes.

Multi objective design optimization of graphene piezoresistive MEMS pressure sensor using design of experiment

This paper investigates the effect of diaphragm thickness, dimensions of piezoresistors, doping profile and temperature compatibility on sensitivity and non-linearity of graphene MEMS pressure sensor. Taguchi method is used for maximizing the sensitivity and minimizing the nonlinearity of the designed pressure sensor. L27 orthogonal array is utilized for five input factors with three levels. Output voltage is obtained from simulation in COMSOL for different combinations of the input parameters as per L27 orthogonal array. It was found that diaphragm thickness and length of the sensing element shows maximum contribution in increasing the sensitivity of the pressure sensor. Similarly, interaction of diaphragm thickness with piezoresistors thickness and doping concentration shows a major contribution in reducing the non-linearity of the pressure sensor. Other factors such as operating temperature affects both sensitivity and nonlinearity of the pressure sensor with a very low contributing percentage of 0.40% and 2.16%, respectively. Pareto Analysis of variance (ANOVA) was employed to validate the predicated results of the designed pressure sensor. The result indicated that the optimum design shows a sensitivity of 4.10 mV/psi with very low non linearity of 0.1%.

Modeling and Optimization of Mitragyna speciosa Extraction using Box Behnken Design

The extraction of kratom (M. speciosa) leaf powder was optimized with preliminary extraction to be further optimized with the Box-Behnken experimental design. The individual and interactive effects of process variables (sample-to-solvent ratio, extraction time, solvent concentration) were assessed. The preliminary extraction results showed that ultrasound-assisted extraction (UAE) and methanol were chosen for further optimization. The experimental data were analyzed by Pareto analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis. The model developed showed a good fit with the experimental data with a high coefficient of correlation (R2) and predictive ability (predicted R2). An optimization study was performed and the optimal extraction conditions were sample-to-solvent ratio value 1.5:10; extraction time of 10 minutes, and methanol concentration of 100%.

Electropolishing Parametric Optimization of Surface Quality for the Fabrication of a Titanium Microchannel Using the Taguchi Method

Titanium is widely used in biomedical components. As a promising advanced manufacturing process, electropolishing (EP) has advantages in polishing the machined surfaces of material that is hard and difficult to cut. This paper presents the fabrication of a titanium microchannel using the EP process. The Taguchi method was adopted to determine the optimal process parameters by which to obtain high surface quality using an L9 orthogonal array. The Pareto analysis of variance was utilized to analyze the three machining process parameters: applied voltage, concentration of ethanol in an electrolyte solution, and machining gap. In vitro experiments were conducted to investigate the fouling effect of blood on the microchannel. The result shows that an applied voltage of 20 V, an ethanol concentration of 20 vol.%, and a machining gap of 10 mm are the optimum machining parameters by which to enhance the surface quality of a titanium microchannel. Under the optimized machining parameters, the surface quality improved from 1.46 to 0.22 μm. Moreover, the adhesion of blood on the surface during the fouling experiment was significantly decreased, thus confirming the effectiveness of the proposed method.

Precision Electropolishing on Fabricating SS 316L Microchannel – A Taguchi Approach

This paper presents the fabrication of a microchannel on stainless steel 316L (SS 316L) by electropolishing method. Machining parameters such as applied voltage, concentration of NaCl in the electrolyte solution and machining gap between tool and workpiece have been optimized in this electropolishing process. The Taguchi method is adopted to ascertain the optimum process parameters in order to increase maximum material removal rate using L9 orthogonal array. Pareto analysis of variance is employed in order to analyze the machining process parameters to the material removal rate. The result shows that the optimal parameters to achieve the maximum material removal rate is by using a combination of 10 V as applied voltage, NaCl concentration of 15 wt.%, and setting 1 cm as the machining gap. It has been also found out that in order to have relatively high material removal without sacrificing the surface quality and the geometrical accuracy of the microchannel produced, applied voltage at 7 V, NaCl concentration of 7 wt.% and machining gap of 3 cm is the best combination of the electropolishing parameters.

Experimental Analysis and Optimization of EDM Parameters on HcHcr Steel in Context with Different Electrodes and Dielectric Fluids Using Hybrid Taguchi-Based PCA-Utility and CRITIC-Utility Approaches

Industries demand stringent requirements towards economical machining without hindering the surface quality while cutting high carbon high chromium (HcHcr) steel. Electrical discharge machining (EDM) of HcHcr steel aims at reducing machining cost (i.e., maximize material removal rate (MRR) and minimize tool wear rate (TWR)) with good surface quality (i.e., minimize surface roughness (SR)). A comparative study was carried out on EDM of HcHcr D2 steel (DIN EN ISO 4957) by applying Taguchi L18 experimental design considering different electrode materials (copper, graphite, and brass), dielectric fluids (distilled water and kerosene), peak current, and pulse-on-time. The process performances were analyzed with respect to material removal rate, surface roughness, and tool wear rate. Pareto analysis of variance was employed to estimate the significance of the process variables and their optimal levels for achieving lower SR and TWR and higher MRR. Hybrid Taguchi-CRITIC-Utility and Taguchi-PCA-Utility methods were implemented to determine the optimal EDM parameters. Higher MRR of 0.0632 g/min and lower SR of 1.68 µm and TWR of 0.012 g/min was attained by graphite electrode in presence of distilled water as dielectric fluid compared to the brass and copper. Additionally, a metallographic analysis was carried out to study the surface integrity on the machined surfaces. Micrographic analysis of the optimal conditions showed lower surface roughness and fewer imperfections (lesser impression, waviness surface, and micro-cracks) compared to worst conditions.

An intensified approach for transesterification of biodiesel from Annona squamosa seed oil using ultrasound-assisted homogeneous catalysis reaction and its process optimization

In this work, Annona squamosa seed oil (ASSO) was extracted using ultrasound-assisted extraction (UAE) and converted into fatty acid methyl esters (FAME) by ultrasound-assisted transesterification (UAT) using methanol and KOH. The multivariable process of UAE and UAT was optimized using a response surface methodology (RSM). The experimental data were analyzed by Pareto analysis of variance (ANOVA) and quadratic polynomial models developed using non-linear regression analysis. A maximum ASSO yield of 31.91% was achieved by the model with the optimum conditions for UAE: liquid-to-solid ratio, 8.8 mL g−1; extraction temperature, 45 °C; sonication time, 19.5 min; and sonication amplitude, 88%. The maximum conversion of ASSO into biodiesel (97.6%) was achieved with the optimum condition of the model: oil-to-methanol ratio, 5.04; catalyst concentration, 1.12%; temperature, 57 °C; and sonication time, 113 min. These models were found to be significant at the 95% confidence level. The transesterified ASSO FAME was characterized using Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), gas chromatography mass spectrometry (GC–MS), 1H-nuclear magnetic resonance (1H NMR), and fluorescence spectroscopy methods. Various physicochemical properties of ASSO and ASSO FAME were characterized according to ASTM standards. The ultrasound-assisted extraction and transesterification process was found to be rapid and simple without any change in the product quality. Importantly, ASSO was found to be a possible new source for potential biodiesel production.

Retracted] Process Development for Edible Film Preparation Using Avocado Seed Starch: Response Surface Modeling and Analysis for Water‐Vapor Permeability

Starch‐based edible films are gaining huge interest in food packaging industries. In the present work, avocado seed starch (ASS) was extracted and used to develop an edible film. The influence of four important process factors, starch, agar, sorbitol, and Tween‐20, was studied on one of the important barrier properties, water‐vapor permeability (WP), of developed edible film. The three‐level RSM design with Box–Behnken approach was carried out to investigate the film property, WP. ASS‐based edible films were prepared by the casting method. The results revealed that the increment in the contents of Tween‐20 and sorbitol reduces the WP of the film. Using the response surface analysis, the effect of the aforementioned factors was analyzed; they showed significant impact on WP. To predict the influence of the selected process parameters, a second‐order polynomial equation was constructed. Additionally, Pareto analysis of variance was employed over the obtained results to investigate the significance of the developed process model.

Optimization of machining parameters when machining beyond recommended cutting speed

Purpose Even though austenitic stainless steels have been extensively used in industries, owing to some of the characteristics of the material, its performance in machining is difficult to understand, in particular at high cutting speeds. There is no availability of dependable and in-depth studies pertinent to this matter. In this work, performance of AISI 304 austenitic stainless steel was studied in terms of surface roughness (Ra) and material removal rate (MRR) at high cutting speeds. Subsequently, parametric optimization and prediction for responses were carried out. Design/methodology/approach Turning operations were conducted using L9 orthogonal array and the outcomes were analyzed to attain optimal set of machining parameters for the responses using signal-to-noise (S/N) ratio and Pareto analysis of variance (ANOVA). In the present work, the cutting speed values were considered beyond the recommended range as designated by tool manufacturers. Finally, multiple regression models were developed to predict responses. Findings From the results, 350 m/min was found to be a significant speed. The investigation reveals that even though the speeds are taken beyond the recommended values, the results are favorable. The optimal machining parameters values for surface quality obtained were cutting speed of 350 m/min, feed of 0.15 mm/rev and depth of cut of 2.0 mm. In case of MRR, the optimal values were: cutting speed of 400 m/min, feed of 0.25 mm/rev and depth of cut of 2.0 mm. It was found out that there was an improvement in Ra and MRR (around 15 and 4%) due to optimization. The results indicate that Pareto ANOVA is easier than S/N ratio. This revealed that the feed rate and depth of cut were mostly affected parameters for Ra and MRR. The developed models are capable of predicting the responses accurately. Practical implications The outcome of the work reveals that even though the speeds were taken beyond the recommended value, the results are favorable for manufacturing industries when the tool cost is considered insignificant. Originality/value No work was reported on machining of the chosen material beyond the recommended cutting speed. Moreover, it was observed from the past works that cutting speeds were limited to 100–300 m/min.

Abrasive water jet machining process parameters optimisation for machining of complex profiled component from Inconel 718 super alloys

The demands for machining complex profile from difficult to machine materials find wide applications in various industries, that has been triggered the neck for development of advanced machining technologies, specifically non-conventional processes and associated optimisation of machining parameter. Keeping in view the applications of Inconel-718 material for aerospace applications, it has been selected as the specimen material for machining complex profiled component on KMT steam line SL-V50 water jet five axes CNC abrasive water jet machine (AWJM) at the research organisation. In the present work AWJM process parameters are optimised by Taguchi-Grey relational method on dimensions, geometries and surface roughness of complex curved contours. Additionally, the Pareto analysis of variance (ANOVA) of Grey relational grade is also applied to find the most significant process parameter. Traverse speed is found to be the most significant process parameter for profile cutting in AWJM, also confirmation experiments were conducted to validate the results. The experiment was done for a specified profile for cross sectional thickness of 6.6 mm and 18 sets of experiments were conducted based on stark's L18 orthogonal array.

ANALYSIS OF WEAR BEHAVIOR OF A NOVEL MAGNESIUM METAL–METAL COMPOSITE

The need of engineered materials with high strength to weight ratio was instrumental for the development of a novel magnesium metal–metal composite with the addition of titanium (reinforcement) and aluminum (alloying element) through disintegrated melt deposition technique. The X-ray diffraction analysis and scanning electron microscopy analysis used to explore the metallurgical insights of the developed magnesium metal–metal composite. Wear tests were carried out with pin-on-disc equipment by varying the input parameters load and sliding velocity over a sliding distance of 2000[Formula: see text]m. Wear was obtained as the output from the experiments, and the same was analyzed through Pareto analysis of variance, to identify the significant parameters. Also, a fuzzy logic-based model was developed to predict the wear behavior of the metal–metal composite. The wear mechanisms involved in the dry sliding wear behavior were analyzed through worn surface analysis and wear debris analysis.

Analysis and Modeling of Mechanical and Barrier Properties of Arracacha Starch-Chitosan Composite Biodegradable Films

This work sought to formulate, analyze, model, and optimize Arracacha (Arracacha xanthorrhiza) starch-chitosan based biodegradable films to assess their use as food coating. To study these films, prepared through the casting technique, a Box–Behnken design was used with three factors at three levels (starch 3–4%; glycerol 0.75–1.25%; chitosan 1–2%) to determine the individual and interactive effects of these parameters on the mechanical properties (tensile TS, and elongation at break, %E) and barrier properties (water vapor permeability, WVP) of the films. The results were analyzed by using the Pareto analysis of variance (ANOVA). The descriptive response surfaces were obtained and second-order polynomial models were developed for each response evaluated, which showed good fit to the experimental data with high determination coefficient (R2 > 0.95), finding relation between the experimental and predicted values. The optimal film formulation, according to the desirability function by Derringer, with the aim of minimizing the SS and WVP values and maximizing the %E values, was obtained with that containing 4% starch, 1.11% glycerol, and 2% chitosan, presenting low stress strain and permeability and high flexibility, conditions favorable for the desired application.

Multi Response Optimization of Green Sand Moulding Parameters Using Taguchi-DEAR Method

Green sand casting is treated as the most versatile casting process due to their excellent design flexibility that offer complex shapes and ability to reclaim silica sand. The modern foundries are looking for alternate moulding materials to partially replace the high cost silica sand. Cow dung is a naturally available eco-friendly binding as well as additive material and is used to partially replace the silica sand. Improper choice of the combination of moulding sand variables, such as degree of ramming, percentage of cow dung, percentage of clay, and percent of water will affect the moulding sand properties and thereby quality of casting. In the present work, Taguchi method is employed to plan and conduct experiments. Pareto analysis of variance is performed to know the contribution of variables on the moulding sand properties (i.e. compression strength, permeability, loss-on-ignition). Taguchi DEAR method is used to determine the single optimal levels of input factors that enhances the performances of all the sand mould properties. Percent of clay and cow-dung found to be the most dominating factor towards all the sand mould properties.

Optimizing dimensional accuracy of titanium alloy features produced by wire electrical discharge machining

ABSTRACTThis study investigates geometrical errors such as cylindricity, circularity and diametral errors of a feature (a hole) produced from wire electrical discharge machining of Ti6Al4V alloy where tension in wire, pulse on time, and flushing pressure are varied. Pareto analysis of variance (ANOVA), Taguchi design of experiment (DoE), and traditional analysis estimate the influence of variables on errors of holes. It was noted that flushing pressure is the most significant factor with individual contributions of 31.02%, 49.5% and 37.84% to circularity, cylindricity, and diametral errors, respectively. The circularity error of holes decreases as the flushing pressure and tension in wire rise, but decreases with the rise of pulse on time. The cylindricity error decreased with the increase of wire tension, flushing pressure and pulse on time. The absolute diametral error reduced as the pulse on time and tension in wire raised, but it raised with the rise of pulse on time. All these trends are associated with the influence of tension in wire on the flexibility of wire, the dependence of heat generation and dissipation on pulse on time, and ability of the flushing pressure to control the cooling, as well as debris removal from the machining zone.

Study of the Effect of Nano-silica Particles on Resin-Bonded Moulding Sand Properties and Quality of Casting

The cast quality in chemical bonded sand mould system is influenced primarily by sand mould properties such as, compression strength, permeability, gas evolution, and collapsibility. Amount of resin and hardener, curing time and number of strokes influence the sand mould properties. The experiments are conducted with the above mentioned input output, as per Taguchi’s L9 orthogonal array. Pareto analysis of variance is conducted to determine the percent contribution of inputs on output, individually. The optimal factor level is determined for each output separately. The conflicting requirements in foundry sand mould properties can be solved by multiple objective optimization. Principal component analysis is applied to determine the relative importance of individual output. Grey relational analysis is used to convert multiple objective functions to a single objective function for optimization task. Pareto analysis is utilized to determine the optimal input factor combination and their relative percent contribution towards moulding sand properties. The nano-silica particles are used as additive to enhance the moulding sand properties. The results have shown that, the nano-silica particles pose a remarkable improvement in sand mould properties and casting quality.

Identification of preferred combination of factors in manufacturing bioepoxy/clay nanocomposites

The current study aims to identify the preferred combination of factors for manufacturing bioepoxy/clay nanocomposites based on epoxidised soybean oil (ESO), including material formulation and manufacturing parameters for maximising tensile strengths of nanocomposites according to Taguchi design of experiments (DoEs). A Taguchi mixed-level DoEs with an L16 orthogonal array was selected. The response was set to achieve the maximum tensile strengths of nanocomposites with a preferred combination of factors determined by the Pareto analysis of variance (ANOVA). The associated results revealed that the ESO content was found to be the most significant factor with a contribution percentage of 66.63% amongst nine factors investigated. This result was followed by two less significant factors, namely mechanical mixing speed and clay content with contribution percentages of 19.09 and 7.01%, respectively. However, other factors of clay type, curing agent type, mechanical mixing temperature and time, as well as sonication frequency and time, were categorised as non-significant factors from the manufacturing and economical point of view. A confirmation test was conducted based on the preferred combination of factors showing good agreement with statistically predicted results.

Ultrasound-assisted extraction of oil from Moringa oleifera Lam. seed using various solvents

ABSTRACTThe present research analyzes the extraction of oil from Moringa oleifera Lam. seed using ultrasound-assisted extraction (UAE) technique under different operating conditions such as temperature, solvent type, and time. Three factors with three levels Box-Behnken response surface design was employed to optimize and investigate the effect of process variables on the response (oil yield). The independent variables showed significant effect on the extraction process. Interactive effects of the extraction process variables were analyzed by Pareto analysis of variance (ANOVA), and second-order polynomial model was used to plot the 3D response surface plot. Optimum extraction conditions for the maximizing the extraction yield of oil (59%) was found to be: temperature of 35°C, solvent type of 2, and time of 20 min. FT-IR was used to analysis the oil. From the results, it can be concluded that the UAE is the effective technique to extract the oil from Moringa oleifera Lam. seed.