Orthogonal Array Research Articles

Efficient hole extraction by doped-polyaniline/graphene oxide in lead-free perovskite solar cell: a computational study

Abstract The intriguing behavior of doped polyanilinine/graphene oxide (PANI/GO) offers a solution to the pivotal problem of device stability against moisture in perovskite solar cell (PSC). Tunable bandgap formation of doped PANI/GO with an absorber layer allows effective flexibility for charge carrier conduction and reduced series resistance further boosting the cell performance. Herein, the L9 Orthogonal Array (OA) Taguchi-based grey relational analysis (GRA) optimization was introduced to intensify the key output responses. Furthermore, this work also delved into incorporating a Pb-free absorber perovskite layer, formamidinium tin triiodide (FASnI3), and concomitantly eluding the environmentally hazardous substance. The numerical optimization supported by statistical analysis is based on experimental data to attain the utmost peak cell efficiency. Taguchi’s L9 OA-based GRA predictive modeling recorded over one-fold enhancement over experimental results, reaching as high as 20.28% power conversion efficiency (PCE). Despite that, the PCE of the structures is severely affected by interface defects at the electron transport layer/absorber (ETL/Abs) vicinity, which is almost zero at merely 1 × 1014 cm−2, manifesting that control measures need to be taken into account. This work deduces the feasibility of ETL/Abs stack structure in replacing the conventional Pb-based perovskite absorber layer, while maximizing the potential use of doped PANI/GO as a hole transport layer (HTL).

Effect of FFF parameters on PLA/WD composite properties: Comparative analysis using Taguchi and GRA approach

This article explores the optimization of 3D printing parameters of PLA/wood dust (PLA/WD) composite material for enhanced physical properties, including density, surface roughness, water absorption, and Shore D hardness. The study employs a Taguchi-based L27 orthogonal array design for experimentation, with mathematical models created using grey relational analysis (GRA) to predict the material’s performance by obtaining a grey relational grade (GRG). The obtained GRG was further optimized using ANOVA. The FFF input parameters analyzed include nozzle temperature (190–200°C), layer height (0.12–0.28 mm), print speed (30–50 mm/min), infill density (80–100%), and raster angle (0–90°). The results indicate that a printing temperature of 195°C, a layer thickness of 0.12 mm, a print speed of 30 mm/sec, 100% infill density, and a raster angle of 45° yield the highest GRG, signifying the best overall performance. Furthermore, the data obtained from Analysis of Variance (ANOVA) indicated that, raster angle has the most substantial influence on physical characteristics, followed by infill %, print speed, print temperature, and layer thickness. The investigation of the sample using Scanning Electron Microscopy (SEM) revealed aspects of the sample morphology, including layer bonding irregularities and empty spaces, which impact the density and hardness of the material.

Experimental-design-based optimization of dispersive liquid-liquid microextraction coupled with gas chromatography–negative-ion chemical ionization–mass spectrometry for the determination of pyrethroids in agricultural products and drinks

Pyrethroids are synthetic chemicals that account for 16% of the international insecticide market and have been shown to be of varying toxicity to different species. There are various methods available for detecting pyrethroids in agricultural products, but these products must be pre-treated to remove interference from the food matrix, such as through dispersion liquid-liquid microextraction (DLLME). This study employed two experimental design methods to optimize the continuous and discontinuous experimental parameters of DLLME and investigated whether DLLME combined with GC-NICI-MS is effective for detecting pyrethroids in agricultural products. The Taguchi design with an L9(34) orthogonal array and response surface methodology were employed to optimize the discontinuous and continuous parameters of the DLLME process, respectively. To validate the performance of GC-NICI-MS after optimized DLLME, pyrethroids in mixed standard solutions at levels ranging from 0.02 to 50.00 µg/L were measured, and the resultant calibration curves were fitted. Adequate linearity was found for the six investigated pyrethroids (r = 0.9908–0.9960). The limits of detection and quantification ranged from 0.005 to 0.035 µg/L and 0.02 to 0.1 µg/L, respectively. The proposed approach simplifies the optimization of parameters compared to reported methods and achieves considerably lower limits of detection. The concept of mixed application based on the dual experimental design method can be applied to other regulated compounds to enhance the safety of agricultural products. The feasibility of the method was confirmed by successfully detecting pyrethroids in 13 types of teas, fruit, and vegetables.

An experimental and modelling approach to proclaim sustainable machining using avocado oil-based nano-cutting fluids

Higher-end science and technology facilitate the human community with a sophisticated life despite it curses by abundant pollution. The alarming demand for sustainability pressurizes the manufacturing sector to ensure sustainable manufacturing. Since Molybdenum di sulfide (MoS2) and avocado oil are known solid and liquid lubricants respectively, hence, it is a worthwhile attempt to implement the bio-based degradable avocado oil enriched with nano Molybdenum di sulfide (nMoS2) particles as a potential machining fluid for CNC-end milling. Different proportions of avocado oil and nMoS2 were used to synthesise four distinct machining fluids to assess the individual impact of avocado oil and nMoS2 particles. The emulsification and sonication were employed to synthesise the fluids. A hybrid Grey Relational Analysis (GRA) coupled with Principal Component Analysis (PCA) was followed to scrutiny the effect of novel machining fluid on machining objectives. The experimental results of physio-chemical properties revealed that avocado-rich 0.5% nMoS2 excels among others. The L16 orthogonal array experiments associated with statistical analysis explored the developed machining fluid (A6W4/0.5) that significantly impacts the machining objectives. The experimental results manifest that nearly 64.87% of surface roughness and 93.3% of tool wear have been reduced during machining in the presence of A6W4/0.5 fluid than A4W6/0.75. The improved performance of the novel machining fluid upholds its potential to replace conventional fluids and ensure green manufacturing.

Constructions of optimal 2-level orthogonal arrays with repeated rows

Constructions of optimal 2-level orthogonal arrays with repeated rows

Influence of water on liquid ammonia-based sustainable dyeing of ramie fiber

Liquid ammonia dyeing emerges as an environmentally benign and sustainable option for the textile industry, characterized by a minimal ecological impact. However, its adoption is hampered by certain limitations, such as suboptimal dye exhaustion and issues with color uniformity, which present significant hurdles to its widespread industrial application. Building on the premise that the addition of water to an ethanol solvent can enhance reactive dye exhaustion in cotton fiber dyeing, this study delves into the dyeing behavior of ramie fiber using a water-liquid ammonia mixture with Reactive Red 195. The incorporation of water into the liquid ammonia solution was observed to marginally decrease the color strength (K/S value) of the dyed ramie fiber, compared to the dyeing with anhydrous liquid ammonia. This reduction is likely due to the diminished expansion of the amorphous regions within the fiber. However, the color levelness of the dyed ramie fiber was enhanced by the addition of water to the liquid ammonia. To decipher the influences on the dyeing process, the Taguchi method, utilizing an orthogonal array (L16), was applied. The analysis revealed that the dye mass factor was the predominant influencer (79.08 %), followed by the liquor ratio factor (18.53 %), with both factors demonstrating statistically significant effects (p < 0.05). A multifaceted analysis of the samples was conducted using advanced techniques such as XRD (X-ray diffraction), FTIR (Fourier transform infrared), TGA (thermogravimetric analysis), and SEM (scanning electron microscopy). These analyses confirmed that the water-liquid ammonia treatment induced changes in the samples’ properties. The treated samples exhibited lower barium activity numbers and breaking force values, indicating structural alterations. Furthermore, the molecular structure of Reactive Red 195 remained intact throughout the dyeing process in the water-liquid ammonia mixture, thereby affirming its viability for practical applications in the textile industry.

A Taguchi-based study on the control factors of reinforced composites with the fiber of coir and pineapple leaves.

The use of composite materials, whether metallic or non-metallic, is becoming more popular nowadays because of some of their superior characteristics compared to the use of wood and metallic materials alone. From this perspective, a new natural fiber reinforced composite by varying the fiber orientation was developed in this study using coir and pineapple leaf fiber. This work uses the Taguchi method to investigate the different effects of control factors on mechanical and physical characteristics of the fabricated natural fiber-based composites. Various control factors were used, including fiber ratios, angles of orientation, and mat types. The testing was conducted in accordance with ASTM standards, and the results were validated through various statistical analyses including Taguchi orthogonal array analysis, confirmation tests, regression analysis, and analysis of variance (ANOVA). Based on the analysis and validation, the highest mean impact strength was found 53.93J/cm2, tensile strength 31.94MPa, flexural strength 46.365MPa, Rockwell hardness number 77, and lower water absorption rate only 3.62%. From the confirmation test, margin of errors was found to be 4.84%, 2.59%, 2.35%, 6.62%, and 2.334% for impact, tensile, and flexural strength, Rockwell hardness, and water absorption test respectively. The variation of the experimental and predicted results was observed from the regression analysis, and it was 2.93 to 0.4J/cm2, 2.12 to 0.79MPa, 3.54 to 0.33MPa, 2.33 to 0.8 RHN, and 0.92%-0.13% for impact, tensile, and flexural strength, Rockwell hardness, and water absorption test respectively. Overall, ANOVA analysis was used to examine the effects of different control variables, and it was discovered that the angle of orientation of fibers had a substantial impact on flexural strength and water absorption rate were 72.30% and 70.89% respectively. Similarly, mat types on tensile strength and Rockwell hardness with 46.47% and 50.67% respectively. In addition, the impact strength was most significantly affected by the wt.% ratio of fibers, which was approximately 50.32%. From the above characteristics and their environmentally friendly behavior, these composites can be used in the place of synthetic fiber-based products.

Construction of asymmetric resolvable orthogonal arrays

Construction of asymmetric resolvable orthogonal arrays

Optimization of process parameters to minimize circularity error and surface roughness in fused deposition modelling (FDM) using Taguchi method for biomedical implant fabrication

Fused Deposition Modeling (FDM) has emerged as a pivotal additive manufacturing technology that enables the creation of complex geometries with high precision and repeatability, particularly in the fabrication of biomedical implants. The functional additive manufacturing components, such as custom prosthetics, dental implants, and surgical guides, are expected to have dimensional accuracy and superior surface finish to ensure biocompatibility, osseointegration, and optimal tissue-implant interaction. This study aimed to optimize the FDM process parameters to minimize circularity error and surface roughness (Ra) using the Taguchi method, with a focus on biomedical implant fabrication. The printing temperature, printing speed, and layer thickness were identified as significant factors affecting circularity and Ra. Orthogonal arrays of Taguchi L9 were devised with three levels of each factor. Circularity and Ra were measured on the printed specimens, which included biomedical implant prototypes. The signal-to-noise (S/N) ratio response analysis determined the optimal parameter combinations. Results showed that the most dominant factor for circularity error reduction was build orientation, while layer thickness had the highest influence on Ra. The confirmation runs validated that the Taguchi-optimized parameters reduced the circularity error by 42% and Ra by 67% compared to default settings. Therefore, the Taguchi method proved effective in identifying the ideal process combinations for biomedical implant fabrication. The findings can help FDM users in the biomedical sector minimize dimensional errors and improve surface finish quality, ultimately enhancing the performance and reliability of medical implants.

Mechanical, thermal and morphological analysis of polylactic acid‐woven glass fiber composites fabricated by additive manufacturing

AbstractPolylactic acid (PLA), a biodegradable thermoplastic, is being used significantly in a wide range of applications because of its environmentally friendly nature. 3D printing is an innovative technique that is used to fabricate polymer composites with complex contours and high precision. Conventional 3D printing technologies use fiber reinforcement in the form of filament. However, fibers in the form of sheets, when used in composite materials, improve the distribution of load and enhance the multi‐directional strength. This study investigates the improvement in the tensile strength of PLA‐based composite by integrating woven glass fibers (WGF) during 3D printing processing. The composites were fabricated using an FDM‐based 3D printer where the WGF sheet was used as reinforcement and PLA filament was used as the matrix material. The main input parameters consist of the number of WGF layers and the orientation of the WGF. Taguchi orthogonal array was used to fabricate composite samples with different combinations of input parameters and then these samples were tested to evaluate the tensile properties. The finding shows that PLA composites reinforced with four layers of glass fiber at 0/90° fiber orientation showed the highest tensile strength of 52.85 MPa and a thermal degradation temperature of 330.49 °C.Highlights 3D printing of WGF‐PLA composite and mechanical characterization. The composite specimen showed the highest tensile strength of 52.85 MPa. The thermal degradation temperature reached 330.49 °C in TGA analysis. ANN predicted the optimal combination of 4 fiber layers with 0/90° orientation. Uniform PLA deposition reduced voids and enhanced interlayer adhesion.

Optimasi Penggunaan Kembali Limbah Karbon Aktif Industri Vetsin Sebagai Biochar Menggunakan Taguchi Orthogonal Array L4

PT XY is a company producing vetsin in the food industry. The company makes extensive use of material resources for its industrial development, which has an impact on the environment. Waste-activated carbon is the result of the color absorption process of the solution. The problem is that the waste generated causes pollution to the company's environment and cannot be stored for long. The average carbon waste generated from January to December 2023 is 86.40 tonnes. Therefore, it is necessary to reuse activated carbon waste into biochar or carbon fertilizer. Processing strategy by conducting experiments using the Taguchi method. Problem identification with an approach that refers to the Responsible Waste Management Hierarchy, and limits the implementation of experiments to the principle of reuse. The Taguchi Orthogonal Array L4 method was chosen for the experimental design because it is more cost-effective than other DOEs and the signal noise is predictable. This research was conducted through experimental methods to know the effect of biochar planting media from activated carbon waste on the growth of kale plants (gr) and get optimal composition variations. As a result, an optimization design was obtained with wet carbon waste material, 25% biochar concentration, and bright light conditions, with an n-gain value of 4.49 resulting in a high improvement category. Comparison of biochar quality with Charcoal Powder from Workplant Store by SNI 06-3730-1995 standard. In biochar products from activated carbon waste, there is a glutamate content of 0.345 g/dL which is a good amino acid for plant growth.

The two‐ and three‐dimensional response spectra: Orientation‐independent intensity measures more suitable for seismic structural design

AbstractThis paper presents two physics‐based, orientation‐independent intensity measures that truly captures the three‐dimensional motion of an orthogonal array of accelerometers and are more appropriate for seismic structural design. This is achieved by processing all three components of the record simultaneously, rather than simply combining the results of processing each component in isolation. Compared to other commonly accepted orientation‐independent intensity measures, it was found that horizontal seismic demand may be systematically underestimated by as much as 29% in the worst‐case scenario. In addition, these new measures are much more computationally efficient than the current ones, as they reduce the number of response spectra calculations per seismic record to just 2 or 3, depending on the measure. Thus, the orientation‐independent intensity measures introduced here optimize the processing of seismic records and may help to reduce the uncertainty of the estimation of the seismic acceleration for structural design.

Optimizing conventional machining process parameters for A713 aluminum alloy using Taguchi method and passive optical network for data transmission

Abstract This study focuses on optimizing machining parameters for A713 aluminum alloy, renowned for its high strength-to-weight ratio but challenging to machine with precision. Using the Taguchi method, key parameters – cutting speed, feed rate, and depth of cut – are optimized to improve surface finish, tool life, and dimensional accuracy. An L9 orthogonal array is applied to enhance experimental efficiency. Furthermore, the integration of Passive Optical Network (PON) technology facilitates real-time data monitoring and transmission, enabling continuous feedback and timely adjustments. This hybrid approach of Taguchi optimization and PON technology achieves superior machining performance, boosting surface quality and operational efficiency. The research highlights how modern data transmission solutions like PON can enhance traditional optimization methods, providing a scalable framework for advanced machining processes in industrial applications.

Surface Characteristics and Performance Optimization of W-Doped Vanadium Dioxide Thin Films

This study explores the surface characteristics evaluation and performance optimization of tungsten (W)-doped vanadium dioxide (VO2) thin films. W-doped vanadium dioxide films were deposited on B270 glass substrates using an electron beam evaporation technique combined with the ion beam-assisted deposition (IAD) method. The Taguchi method was used to analyze the performance optimization of VO2 thin films, and L16 orthogonal array design and Minitab software were used for optimization calculations. The surface roughness, visible light transmittance, infrared transmittance, and residual stress of un-doped and tungsten-doped (3–5%) VO2 thin films are set as the quality performance indicators of thin films. The goal is to identify the key factors that affect the performance of VO2 thin films during deposition and optimize their process parameters. The experimental results showed that a VO2 thin film with 3% tungsten doping, an oxygen flow rate of 60 sccm, a heating temperature of 280 °C, and a film thickness of 60 nm exhibited the lowest surface roughness of 2.12 nm. A VO2 thin film with 5% tungsten doping, an oxygen flow rate of 0 sccm, a heating temperature of 280 °C, and a film thickness of 60 nm had the highest visible light transmittance at 64.33%. When the oxygen flow rate was 60 sccm, the heating temperature was 295 °C, the film thickness was 150 nm, and the tungsten doping was 5%, the VO2 thin film showed the lowest infrared transmittance of 31.34%. A thin film with 5% tungsten doping, an oxygen flow rate of 20 sccm, a heating temperature of 265 °C, and a film thickness of 120 nm exhibited the lowest residual stress of −0.195 GPa.

Calibration of iPad Pro LiDAR Scanning Parameters for the Scanning of Heritage Structures Using Orthogonal Arrays

The deterioration of historical heritage has underscored the need for precise documentation and accurate measurements in restoration and conservation efforts. Detailed documentation not only enhances understanding but also provides architects and engineers with the necessary tools to optimize these processes. However, limited funding has prompted researchers to develop low-cost geomatic tools and methodologies, such as multi-image photogrammetry, to generate 3D point clouds. Technologies like miniaturized Light Detection and Ranging (LiDAR) sensors, integrated into Apple devices such as the iPhone and iPad since 2020, have made these tools more accessible. These sensors deliver direct time-of-flight measurements, enabling accurate 3D data acquisition of historical structures. Despite the critical role that scan parameters—such as scanning speed, sensor angle, lighting, or the distance from the scanned object—may play, there is a lack of detailed studies examining their effects in the literature. To address this gap, this paper employs Taguchi’s orthogonal arrays to define the optimal scan parameters for the LiDAR sensor on the 2022 iPad Pro. The optimized parameters are then used to scan a historical building.

Exploration of Engine Parameters for Emission Reduction in Gasoline-Ethanol Fueled Engines

The main objective of this study is to develop spark ignition engine parameters that allow complete combustion while reducing dependence on fossil fuels. To achieve this goal, optimization of compression ratio, gasoline-ethanol mixture, ignition timing, and spark plug type was used. In addition, this study used water injection that continuously injects water before the intake manifold. In this study, the Taguchi method with the L9 orthogonal array was applied. According to the experimental verification results, the best combination to reduce exhaust emission levels is to utilize gasoline-ethanol (E70), a compression ratio (CR) of 15.6:1, an ignition degree of +4°, and a platinum spark plug. Meanwhile, the presence of water injection at 1.45 ml/s helps reduce vehicle exhaust pollutants.

A Study on Electroless Copper Deposition for Desktop Stereolithography 3D Printing Materials

Electroless deposition is a method of metallizing parts without needing for an electrical source that can be performed on electrically conductive and non-conductive materials. Adhesion quality is an essential aspect of the electroless deposition process that determines the metal deposition conditions. The properties of stereolithography (SLA) 3D printed parts can be improved through the metallization process for various applications. In this study, optimization through the orthogonal design method was used to obtain the optimal processing parameters of electroless copper deposition on desktop SLA material with respect to adhesion quality. Experimental work was carried out according to the L9 (34) orthogonal array, followed by an evaluation of the signal-to-noise (S/N) ratio and analysis of variance (ANOVA). Based on the S/N ratio results, the optimal processing parameters for adhesion quality were potassium hydroxide concentration (400 g/L), etching time (30 min), formaldehyde concentration (3.75 mL/L) and deposition time (30 min). The results of the study are useful for industries such as rapid tooling, rapid prototyping, and semiconductors.

OPTIMIZATION OF CYCLE TIME AND REDUCTION OF TAILED ON TOP DEFECTS IN BOTTLE CAPS USING TAGUCHI METHOD

The purpose of this study is to determine the optimal cycle time and reduced defects of tailed on top in bottle cap products. Defects of tailed on top are defects in the form of residual plastic material that hardens at the top of the bottle cap where the material enters when injected. The method used in this final project was to conduct an experimental design using orthogonal array by varying the influential parameters and ANOVA calculation. Furthermore, this paper also calculated the Taguchi method by using Minitab 18 software. The result show that the optimal condition is combination parameters cooling time of 8 seconds, injection time of 2.10 seconds and hot runner nozzle temperature of 230oC produces a cycle time value of 17,11 seconds and percentage defects 1,56%.

Numerical Simulation of Uplift Behavior of a Rock-Socketed Pier Anchored by Inclined Anchors in Rock Masses

The rock-socketed pier anchored by inclined anchors (RPIA) is a new type of foundation developed by combining a rock-socketed pier and inclined anchors. Current research on RPIA is relatively limited, and the impact of design parameters on its bearing performance remains unclear. To investigate the uplift-bearing performance of RPIA, a finite-element model that considers the nonlinear properties of materials and multidirectional interactions was developed and verified. Based on this model, numerical simulations were performed on twenty-five RPIA that were designed using the L25 orthogonal array proposed by the Taguchi method, and the uplift load–displacement curve for each RPIA was obtained. Based on the interpretation of the elastic limit, uplift resistance, initial stiffness, and the ductility index for each simulated RPIA, the sensitivity of each factor was examined by analyzing the signal-to-noise ratio and variance. The results indicated that rock strength and pier diameter were the main factors determining the uplift performance of the RPIAs, while the angle of inclined anchors is the most influential factor affecting the ductility of RPIA. The primary role of the inclined anchor is to reduce the extraction of the pier after failure of the side resistance between the pier and rock mass, thus significantly enhancing the ductility of the uplift-loaded RPIA. The addition of reinforcements around the connection joints of the pier and anchors may prevent concrete failure and to fully execute the role of inclined anchors.

Optimization of preparation parameters of palm oil-based nanofuel with multi wall carbon nanotube (MWCNT) for stability using Taguchi-grey relation analysis (GRA) combination

This research optimizes the preparation parameters of palm oil-based nanofuel and Multi Wall Carbon Nanotube (MWCNT) to produce stable nanofuel. The parameters optimized include stirrer speed, sonication time, sonication power, and surfactant ratio, with stability measured through absorbance and sedimentation ratio (SR). The Taguchi method, using an L9 orthogonal array designed with minitab 19.0 software, was employed for single-objective optimization, while Grey Relation Analysis (GRA) is applied for multi-objective optimization. Experimental results show that the optimal conditions for absorbance are stirrer speed of 1000 rpm, sonication time of 30 minutes, sonication power of 200 watts, and surfactant ratio of 1, whereas for sedimentation ratio the optimal conditions are stirrer speed of 1000 rpm, sonication time of 30 minutes, sonication power of 150 watts, and surfactant ratio of 1. ANOVA analysis reveals that surfactant concentration contributes the most to nanofuel stability, with contributions of 79.63% for absorbance and 82.60% for sedimentation ratio. Multi-objective GRA optimization results also show that surfactant concentration is the most dominant factor, contributing 71.5% to the Grey Relational Grade (GRG). The consistency of optimal parameters yielded by both Taguchi and GRA methods reinforces the validity and consistency of this study's results. This research provides a strong foundation for the development of more stable nanofuels, potentially enhancing energy efficiency and sustainability. These findings offer practical guidelines for real-world applications and make significant contributions to nanofuel technology