Experimental Design Method Research Articles

Digital Learning Media in Learning to Write Poetry for Middle School Students

Research has been carried out entitled Digital Learning Media in Learning to Write Poetry for Middle School Students. This research aims to determine the influence of digital learning media on the learning outcomes of class VIII students at SMPN 02 Woja. This type of research is quantitative research using the Quasi Experimental Design method, especially the non-equivalent control group design type. From the learning results obtained before treatment, both the experimental class and the control class showed the same abilities. Next, the posttest value data was tested. The results of the posttest analysis show that the average score for the experimental class is 51.21, while the average score for the control class is 41.70. Based on inferential statistical analysis of the posttest scores, it was found that the calculated t value (t_count) was 1.99 greater than the t table value (t-table) of 1.669. This shows that H0 (null hypothesis) is rejected and H1 (alternative hypothesis) is accepted.

Use of optimization methods in the calculation of slope stability

This article focuses on studying and identifying factors that contribute to ground movement and determining appropriate methods for verifying slope stability. Depending on the type of soil, the geometry of the slope and the type of work to be carried out, it is appropriate to choose a suitable technical solution, adapted both to the nature of the soil in place and to its environment. The major techniques that can be used to increase the mechanical properties of soils are the modification of the internal structure of the existing soil and the reinforcement of the soil by the addition of materials and inclusions. These techniques make it possiblte to improve the compactness and bearing capacity of the soil in place. The case presented in this research was studied using a two-dimensional finite element model, to study the effect of various mechanical characteristics of the soil, including cohesion (C), friction angle (φ), the reference module (Eref) and the backfill volume. We examined the influence of the coupling on the safety factor and the location of the sliding surface to have an optimal slope design. To do this, we formulated the problem into an optimization framework using MINITAB 19 software. This framework will use a design of experiments (DOE) approach to identify the optimal combination of factors ensuring slope safety. The results obtained will be analyzed to evaluate the effectiveness of the DOE method in determining the most favorable combination of parameters. We expect the mechanical properties of the slope to have the most significant influence on the factor of safety and the location of the sliding surface.

Analysis and Testing of Pre-Cut Sugarcane Seed Stalk Sawing Performance Parameters

Sugarcane is an important economic crop in tropical and subtropical regions. Presawing planting is an important method for achieving automated and precise planting with sugarcane planting machines. The sawing process is a key stage in planting management, affecting not only the germination and survival rates of sugarcane, but also reflecting the mechanical performance of sawing. To reduce the peak sawing force and enhance the sawing surface quality of sugarcane seedlings, this study utilized a central composite experimental design method. Single-factor and multi-factor experiments were conducted with a specially designed sugarcane stalk sawing experimental rig to investigate the impact of factors such as the stalk diameter feeding speed, and sawing speed on the peak sawing force and sawing surface quality. Upon being developed and validated, multivariate mathematical regression models elucidated the relationships among these factors. The experimental results showed that the order of influence of each factor on the peak sawing force was the stalk diameter, feed speed, and sawing speed, while for the sawing surface quality, the sequence was the sawing speed, stalk diameter, and feed speed. Correspondingly, the determination coefficients for the peak sawing force and sawing surface quality prediction models were 0.9708 and 0.9675. With a maximum error of 7.6% for the peak sawing force and an average relative error of 7.1%, and a maximum error of 3.5% for the sawing surface quality and an average relative error of 2.83%, the calculated results from the regression models were in good agreement with the experimental findings. This indicates that the models are capable of quickly and accurately predicting the peak sawing force and sawing surface quality of sugarcane stalks under different conditions. The research findings provide valuable insights for the development and optimization of sugarcane stalk presawing equipment and related experimental studies.

Influence of AWJ Process Parameters on Erosion Groove Formation in Additively Manufactured Stainless Steel.

The presented manuscript focuses on the influence of process parameters of abrasive water jet technology on the creation of non-transient erosive grooves. The processed stainless steel SS 316L is additively manufactured using the selective laser melting (SLM) method. Due to the distinct mechanical properties of this material resulting from the production process, the material was machined in two planes according to the direction of the printing layers. The experimental part employed a planned experiment utilizing the DoE (Design of Experiment) method. Experiments aimed at varying process parameters (traverse speed, standoff distance, abrasive mass flow) were conducted at a water pressure of 50 MPa, assessing the parameters' impact on the removed material and the properties of the resulting non-transient erosion groove. The properties of the erosion groove, such as shape and the material removal (area of erosion groove), were evaluated. The influences of process parameters on the observed parameters were assessed using the analysis of variance (ANOVA) method. Experiment preparation and setup were based on a thorough theoretical analysis of the machining process with the abrasive water jet (AWJ) method. The experiment also highlights the diverse properties of the SS 316L material prepared using the SLM method when machined with AWJ technology.

Logistics service failures and recovery strategies: is the response time or the discount amount more important?

PurposeAlthough trade volumes in e-retailing have increased significantly in recent years, logistics service failures are inevitable, especially at the delivery stage. Therefore, it is essential to provide customers with effective recovery strategies to increase their satisfaction and repurchase intentions. There is a lack of empirical evidence on whether the response time or the discount offered in compensation is more crucial for customers. Therefore, this study aims to determine whether the response time or the discount offered for high and low criticality failures has a greater impact on customer satisfaction levels and repurchase intentions for female and male customers.Design/methodology/approachA scenario-based experimental design method has been adopted to collect data, and 697 participants aged 18 and 58 years have been reached. The research utilized a between-subjects design, incorporating three factors: gender (female vs male), criticality (high vs low) and compensation (7 days: 10% discount, 10 days: 20% discount and 14 days: 30% discount). Six scenarios depicting the failure of an online retailer were created, and factorial univariate ANOVA was conducted to test the hypotheses.FindingsThe study's results show that in terms of customer satisfaction, female customers attach more importance to the response time in the case of high criticality and the amount of discount offered in the case of low criticality. On the other hand, male customers give more importance to the response time in terms of customer satisfaction when they experience a high or low criticality failure. In the case of low criticality, response time is more important for male customers to increase their repurchase intentions, while the amount of the discount is more important for female customers.Originality/valueThe study demonstrates the relative importance of the response time and discount amount according to the criticality level of failures and to guide business managers in terms of the recovery strategies they will implement. It focuses on gender differences and determine whether the response time or discount amount is more important for male and female customers in high or low-criticality situations.

Design of inductive electrostatic boom spray system based on embedded closed electrode structure and droplet distribution test in soybean field.

The large water demand, insufficient deposition on the back of the leaf and the uneven distribution of droplets are the problems of traditional agricultural ground plant protection machinery, which leads to low agricultural control efficiency. Combined with the advantages of electrostatic spray technology and the characteristics of high working efficiency and low probability of droplets drift of ground sprayer, an inductive electrostatic boom spray system based on embedded electrode structure is designed and mounted on a large self-propelled boom sprayer for field testing. Based on the working characteristics of the fan nozzle and the analysis of the theory of charge, the inductive electrostatic spray device is designed. The performance of the device is tested and the rationality of the system design is verified by COMSOL numerical simulations, charge-to-mass ratio, and particle size distribution measurements. The spray deposition scanning software and the Box-Behnken experimental design method are used to analyze the spray droplet deposition rate and coverage density of the sprayer on the front and back of the target leaves. The results show that the embedded closed electrode structure designed in this paper can avoid the problem of electrode wetting, and the electric field generated by it is mainly concentrated in the spray liquid film area, and the intensity reaches 6~7 V/m. At the conventional application height (500 mm), the maximum charge-to-mass ratio is 2.91 mC/kg, and the average particle size is 168.22 μm, which is 12.87% lower than that of ordinary spray, when the spray pressure is 0.3 MPa and the electrostatic voltage is 12 kV. The results of field experiments show that the optimum combination of the working parameters with the spray speed is 8.40 m/s, the spray pressure is 0.35 MPa, the charging voltage is 11.50 kV, the amount of droplet deposition in the lower dorsal area of the blade is 1.44 µL·cm-2. This study can provide a certain basis for the application of electrostatic spray technology in ground sprayers.

Guided experimental design for static nonparametric modeling

Sequential or goal-oriented experimental design methods help achieve the target cheaply and quickly. In this work, we exploit Bayesian Optimization to obtain accurate and reliable static models for physical phenomena in cases where parametric models are unavailable. Our Guided Design of Experiments (G-DoE) workflow is proposed with a purely explorative acquisition function and an empirical stopping criterion. Two stopping criteria are proposed, one that is based on convergence rates of the prediction uncertainty and another that is based on a tolerance limit. Stopping criteria thresholds are established by studying factors like noise level and dimension size and their impact on prediction uncertainty convergence. Furthermore, we compare the G-DoE framework with classical Full Factorial and Response Surface strategies in terms of the suggested number of experiments and corresponding accuracy of fit. The proposed algorithm is tested using a methanol synthesis reaction experiment, a vapor pressure experiment, and a synthetic example.

Flexural behaviour of built-up I-shaped bamboo scrimber beams: experimental tests and design method

ABSTRACT This paper presents the flexural behaviour of built-up I-shaped bamboo scrimber beams under four-point bending. Ten bamboo scrimber beams were tested, employing different types of connections between the web and flanges. The load-deflection relationship, failure mode and load-slip relationship of beams were obtained through experimental tests. Besides, the measured strains of bamboo scrimber in various regions were used to analyse the flexural mechanisms of I-shaped beams. Test results showed that the beam with a glued connection exhibited debonding at the web-flange interface, hindering the development of flexural capacity of the beam. By using self-tapping screws or bolted steel angles to strengthen the connection, the slip between the web and flanges was considerably reduced, resulting in the increased flexural capacity of beams. The rupture of the bottom flange near the concentrated point load led to the final failure of strengthened beams. The design method for mechanical fastened glulam beams in Eurocode 5 was adopted to assess the flexural capacity of bamboo scrimber beams. Comparisons between experimental results and calculated results per Eurocode 5 indicate that the method is capable of predicting the flexural resistances of I-shaped bamboo scrimber beams with reasonably good accuracy.

New design of materials, order and thicknesses of an aircraft windshield behaviour layers to increase its resistance against repeated bird impacts

Abstract There are instances when an aircraft encounters a bird’s flock or faces a heavy hailstorm, causing the windshield to sustain consecutive impacts. Therefore, the investigation of windshield resistance against repeated impacts is crucial. In this research, various tests such as tensile, split Hopkinson pressure bar (SHPB), and three-point bending are conducted to extract the mechanical properties of the materials used in a five-layers windshield under high strain rates. Using this information, the bird impact on the windshield is simulated using the smooth particle hydrodynamics (SPH) method, and the results are compared with real bird impact test outcomes, and the validation of this simulation is confirmed. The simulation of two consecutive bird strikes indicates the current windshield lacks sufficient resistance against successive dual impacts; in such scenarios, the second bird penetrates the windshield after breaking it and tearing the interlayer. Considering new materials and thicknesses for each windshield layer, a Taguchi experimental design method is employed to examine various layer arrangements with different materials and thicknesses. The configurations in which the windshield can withstand a maximum of three bird impacts in succession are identified. Subsequently, using the “the smaller, the better” criterion in the Taguchi optimisation approach, the configuration that not only prevents bird penetration but also minimises the maximum strain in the inner layer is selected as the desired outcome. Thus, a new five-layer windshield with new materials and thicknesses is presented, which is resistant to the repeated collision of up to three birds, tearing in the interlayer and bird penetration does not happen.

Experimental and Numerical Investigation Integrated with Machine Learning (ML) for the Prediction Strategy of DP590/CFRP Composite Laminates.

This study unveils a machine learning (ML)-assisted framework designed to optimize the stacking sequence and orientation of carbon fiber-reinforced polymer (CFRP)/metal composite laminates, aiming to enhance their mechanical properties under quasi-static loading conditions. This work pioneers the expansion of initial datasets for ML analysis in the field by uniquely integrating the experimental results with finite element simulations. Nine ML models, including XGBoost and gradient boosting, were assessed for their precision in predicting tensile and bending strengths. The findings reveal that the XGBoost and gradient boosting models excel in tensile strength prediction due to their low error rates and high interpretability. In contrast, the decision trees, K-nearest neighbors (KNN), and random forest models show the highest accuracy in bending strength predictions. Tree-based models demonstrated exceptional performance across various metrics, notably for CFRP/DP590 laminates. Additionally, this study investigates the impact of layup sequences on mechanical properties, employing an innovative combination of ML, numerical, and experimental approaches. The novelty of this study lies in the first-time application of these ML models to the performance optimization of CFRP/metal composites and in providing a novel perspective through the comprehensive integration of experimental, numerical, and ML methods for composite material design and performance prediction.

Keratin extraction optimization from poultry feather using response surface- Box-Behnken experimental design method

This study aimed to develop a cost-effective method for managing chicken feather waste by hydrolyzing it in an alkaline medium to extract keratin hydrolysate. Through a Box-Behnken experimental design, the effects of NaOH solution concentration, temperature, and extraction time on the extraction process were examined. Analysis of the extracted keratin hydrolysate revealed the presence of key functional groups and characteristic protein structures. Optimization efforts identified 0.65 N NaOH solution concentration, 70 °C temperature, and 1-h extraction time as yielding the highest protein yield of 89.71 %. These findings underscore the potential of alkaline hydrolysis as a sustainable approach for both waste management and the extraction of valuable keratin hydrolysate. This research contributes to addressing the challenges faced by poultry farms in waste management while offering avenues for the utilization of keratin in various applications, thereby promoting environmental protection and human health.

Investigation of The Potentials of Sisal-Palm Slag Composites as Materials for Asbestos-Free Brake Pad

Asbestos conventionally used as frictional materials in brake pads causes environmental pollution and is unsafe for human health. This study’s goal was to assess alternative brake pads made from sisal-palm slag. Ten composite brake pads were produced by combining sisal-palm slag with epoxy resin, silica and steel slag using formulations obtained from the rule of mixture experimental design method. The produced brake pad composites physical properties (density (ρ), porosity (φ) and tribo-mechanical properties (wear rate (Ŵ), hardness (HB), compressive strength (σ) were evaluated. From the results, the control sample (Auto-boss brake pad) recorded values of 1.7800 g/cm3, 18%, 1.127 mg/min, 110BHN and 43.204N/mm2 for ρ, φ, Ŵ, HB and σ respectively. The best performing sample was sample 5 with recorded values of 1.3329 g/cm3, 23.40%, 1.143mg/min, 102.28BHN and 39.642 N/mm2 respectively, while sample 9 was the least performing samples with recorded values of 1.3123 g/cm3, 30.43%, 1.571mg/min, 76.77BHN and 26.74 N/mm2 for the above parameters respectively. The study showed that the produced samples offered comparable performance to that of asbestos-based and hence could serve as possible replacement for them.Keywords: Brake Pad, Asbestos, Pin on Disc Wear Tester, Hardness, Sisal, Palm Slag, Porosity

Physical and Hardness Performance at Different Surfaces for Titanium Alloy (Ti6Al4V) Printed Using Selective Laser Melting Process (SLM)

elective laser melting (SLM) 3D product is capable of producing varied surfaces such as top, core and bottom surface depending on the product dimensions and building orientation. Each surface may have differences in physical and mechanical properties such as surface roughness, microhardness, and microstructure. Therefore, this study examined the effects of SLM processing parameters as well as volumetric energy density (VED) on surface roughness, microhardness and microstructure on different 3D product surfaces. In this study, a sample of titanium alloy cube (Ti6Al4V) with different surfaces of up skin 1 (US1), up skin 2 (US2), core skin (CS) and down skin (DS) are printed on a 30° building orientation printed through the SLM process. There are nine sets of parameters printed based on the Taguchi 𝐿9 experimental design method. All printed cube samples were heat treated to remove the residual stresses generated during the printing process. The effect of processing parameters on micro hardness as well as microstructure on each surface has been studied. This study found that SLM printed Ti6Al4V produced almost identical surface quality for different surfaces of the cubic samples. Surface roughness of US2 ranging between 15.38 µm and 26.22 µm, while DS is slightly rougher with surface roughness in the range of 16.05 µm and 27.64 µm. Microhardness in the nine processing sets however was found to have a bigger difference in values of 387 ± 10 HV (US2) and 362 ± 10 HV (DS). In general, US2 surfaces were found to have high microhardness compared to the DS surfaces due to the formation of long, straight needle-like martensitic microstructure.

Advanced hybrid composites: A comparative study of glass and basalt fiber reinforcements in erosive environments

AbstractThis study looks at how erosive wear affects hybrid composites made by vacuum infusing glass and basalt fibers into an epoxy matrix. The study uses garnet abrasives and a design experiment method to test how resistant these hybrid composites are to erosion at 30°, 60°, and 90° angles of impact. The analysis included three‐dimensional profilometry and scanning electron microscopy. Results show that glass layers enhance erosion resistance, whereas basalt layers increase wear. Key quantitative findings include erosion rates and mass loss, highlighting impingement angle and erosion time as critical factors. At a 30° angle, basalt exhibited more severe wear (erosion rate: 0.8090 mg/g for 20 s) compared to glass (erosion rate: 0.5683 mg/g). Conversely, at 90°, the erosion rate for basalt decreased to 0.3643 mg/g, indicating a decreased sensitivity to this steeper angle. According to the ANOVA, impingement angle and erosion time account for 30.08% and 50.25% of the erosion rate variance, respectively. These findings advance our understanding of material behavior in hybrid composites and emphasize the strategic selection and layering of materials for enhanced durability. This research contributes to developing more sustainable composites, demonstrating natural fibers' potential to improve mechanical properties and erosion resistance.Highlights Glass layers enhance durability against erosive forces in hybrid composites. Basalt layers accelerate erosion rates, showing a need for strategic layering. Glass fiber reinforcement significantly improves wear performance. Hybrid constructions with glass a top basalt balance flexibility and durability. Emphasizes eco‐friendly advantages of natural materials in composites.

Comprehensive evaluation on deposition and heat transfer performance of the mixed tube bundle based on orthogonal experimental study

Deposition on heat exchange surfaces is an urgent problem to be solved to achieve efficient utilization of energy in thermal equipment. To mitigate deposition and the resultant heat attenuation, this work proposes a mixed tube bundle strategy of inserting attached cylinders behind the tube bundle, which can effectively meet the design requirements of high anti-deposition performance, high heat transfer efficiency, and low flow resistance. An integrated dynamic model for deposition is developed to elucidate the effect of ash particles on deposition, flow, and heat transfer characteristics. Based on the inverse distance weighting interpolation, a dynamic mesh smoothing technique is employed to simulate the evolving deposition layer on the heat transfer surface. In addition, the L16(43) orthogonal experimental design method is adopted to study the influence of the arrangement angle, diameter, and distance to the primary bundle of the attached cylinder on the overall performance, and determine the optimal scheme. The results show that deposition in the cases using the mixed tube bundle strategy has significantly decreased. The weakening effects of the attached cylinder on the deposition of small-medium particles and large-sized particles are due to the inhibition of vortex development in the gap of tube bundle and the deviation of the motion trajectory, respectively. The novel design exhibits the lowest deposition mass Mdep = 1.12 g and the best comprehensive performance PEC = 1.14 under the condition of the arrangement angle of 50°, the diameter of 10 mm, and the distance between the primary bundle of 5 mm. The obtained results can provide reference schemes and guidance for the optimization of the design of heat exchange equipment and accessory devices.

Respon Pertumbuhan Tanaman Sawi Pagoda (Brassica narinosa L.) dengan Pemberian Pupuk NPK dan Pupuk Cair dari Limbah Organik

Continuous use of inorganic fertilizers results in problems with soil quality. One solution to reduce this problem is the use of a combination of inorganic fertilizer and liquid fertilizer from organic waste. This research aims to obtain a combination of NPK fertilizer and liquid fertilizer from organic waste that has the best effect on the growth of pagoda mustard plants. The research method used was the single-factor randomized group design (RAK) experimental method. The factors tested were a combination of NPK fertilizer and liquid fertilizer from organic waste with 8 treatments, namely A (300 kg/ha NPK fertilizer + 0 ml/l liquid fertilizer from organic waste), B (0 kg/ha NPK fertilizer + 200 ml/ l liquid fertilizer from organic waste), C (200 kg/ha NPK fertilizer + 100 ml/l liquid fertilizer from organic waste), D (200 kg/ha NPK fertilizer + 200 ml/l liquid fertilizer from organic waste), E ( 200 kg/ha NPK fertilizer + 300 ml/l liquid fertilizer from organic waste), F (100 kg/ha NPK fertilizer + 100 ml/l liquid fertilizer from organic waste), G (100 kg/ha NPK fertilizer + 200 ml/ l liquid fertilizer from organic waste), H (100 kg/ha NPK fertilizer + 300 ml/l liquid fertilizer from organic waste). Consisting of 8 treatments and 5 replications. The results of the analysis of variance and DMRT level of 5% showed that the combination of NPK fertilizer and liquid fertilizer from organic waste had no significant effect on plant height or root length. Keywords: Pagoda mustard greens, NPK fertilizer, liquid fertilizer, organic waste

Efektivitas Layanan Bimbingan Kelompok dalam Meningkatkan Kecerdasan Emosional Siswa

Low emotional intelligence can have negative impacts on yourself and others because you cannot take an appropriate attitude. Therefore, group guidance is very necessary to increase students’ emotional intelligence. The research method used is Quantitative with a Pre-experiment design Experimental method. The reseach subjects 11 students MTsN 11 Agam those selected using Purposive Sampling technique. Data analysis used the Wilcoxon Signed Rank Test. The results of student data analysis after following group guidance 5 times stated that there was a significant difference in scores between the pretest and posttest of students’emotional intelligence after following group guidance.

Simultaneous Cd2+ and organic matter sorption behavior on various microplastics: Modeling of influencing factors using the Taguchi method

In aquatic environments, microplastics (MPs) can serve as a vector for pollutants. Pollutants adsorbed on the surface of microplastics pose a potential risk to aquatic organisms. In this study, the effect of environmental conditions such as duration, pH and conductivity on the Cd+2 and organic matter adsorption capacity, qe,Cd and qe,COD of microplastic type was evaluated using the Taguchi experimental design method. ANOVA results showed that the most effective factor in adsorption capacity was the microplastic type. qe,Cd were listed as > 0.6–0.8 mg/gPP, >0.4 mg/gMDPE, 0.2 mg/gLDPE at 50 mS/cm. It was observed that conductivity had a positive effect on qe,Cd.,qe,Cd for PP in waters with conductivities of 50 mS/cm, 0.8 mS/cm, 0.02 mS/cm at pH 7.0 was found to be ≫ 0.6, >0.2, > 0.4, respectively. qe,Cd and qe,COD showed similar trends. It was determined that the qe,COD at 50 mS/cm was in the order of 15–22 mg COD/gPP, 5–10 mg COD/gMDPE, but not determined for LDPE. After MW and UV artificial aging, qe,COD of virgin PP increased by 31.5 % and 94.4 %, respectively, whereas the qe,Cd decreased by 1.2 % and 24 %.

Development of a wet digestion method for the analysis of metal soap in fat, oil, and grease deposits using the Taguchi method

Conventional methods for evaluating lipid-based metal salts in fats, oils and grease (FOG) deposits often fall short in assessing the efficiency of grease interceptors for food service establishment wastewater, primarily due to their inadequate specificity for fatty acid (FA) metal soaps. To address this issue, this study introduces a wet acid digestion method developed for the accurate analysis of metal soap content in FOG samples. The Taguchi experimental design method was used to determine the optimal conditions for digestion including temperature, contact time, solid/liquid ratio and type of acid mixture with the aim of more accurately quantifying metal salt concentrations. This work focused on identifying the most effective acid combinations for digesting FOG to enable analysis of commonly found metals. Extensive comparisons revealed that HNO3:H2SO4:H2O2 (1:2:1) and HNO3:H2O2 (1:3) were particularly effective at 180°C for 16 h due to their significant oxidation potential. The HNO3:H2O2 (1:3) mixture yielded the highest concentrations of Ca, Mg, Na, and K of 296.38±0.66, 54.95±1.01, 247.65±2.27, and 46.09±3.44 mg/g, respectively, aligning with the stringent optimisation principles of the Taguchi method. A one-way ANOVA test validated significant variances in metal contents (p < 0.005), and a t-test indicated a notably higher concentration of Ca compared to other metals. The study presents a sophisticated approach to evaluating the FA metal soap content of FOG ensuring enhanced accuracy and precision compared to established methods.

Investigation of Machining Parameters for Turning Process

Manufacturing industries mainly concentrates on how to minimize the cost of the products. The process planers have to prepare the process plan of the product based on the availability of the recourses. All the information is available in the plan including inspection and delivery date of the product. Based on the recommendation of the manufacturing and inspection methods, components are produced at affordable cost. Most of the research work concentrated on selection of machining parameters using optimization techniques and also prove that the machining time / cost were minimized for the particular components / operations. In this work, tool nomenclature is to be considered for the investigation for selection of machining parameters. Work presents an experimental investigation of the influence of the three most important machining parameters of depth of cut, feed rate and spindle speed on surface roughness during turning of aluminium alloy. In this study, the design of experiment which is a powerful tool for experimental design is used to optimize the machining parameters for effective machining of the work piece. L9 orthogonal array experimental design method as well as analysis of variance (ANOVA) is used to analyse the influence of machining parameters on MRR &amp; Machining Time. Two different grade of aluminium alloy i.e. AL 6063 &amp; AL 6068 were machined with input parameters of depth of cut and speed. The output parameters are MRR and machining time. Based on the results empirical equations are formed and optimized results are validation .The optimal results are recommended to manufacturing industries.