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The purpose of this paper is to discuss the capability of finite element analysis (FEA) in performing the virtual thermal cycling reliability test to evaluate the reliability of solder joints in a ball grid array (BGA) package.

Thermal cycling test has been used to evaluate the reliability or fatigue life of the solder joints in BGA package using commercially available FEA software, ANSYS™. The effect of different temperature cycling condition is studied by applying different value of dwell time and ramp rate. Two types of analyses are used namely, the physics‐based analysis and the statistical‐based analysis. Two screening design methods namely, central composite design (CCD) and Box‐Behnken Matrix Design method are used to isolate the most important factors amongst six selected design variables. The optimization process is carried out using response surface methodology (RSM).

It is observed that changes in ramp rate produce significant effect in solder fatigue life than changes in dwell time but the dwell time at high temperature has a negligible contribution to solder fatigue life. It has been found that the thickness of the mold has a significant effect on the performance of the solder joint reliability (more than 50 percent) as compared to that from other factors. Besides, the effect of individual factor, the interaction among factors also changes the solder joint reliability. RSM based on Box‐Behnken Matrix design offers the highest characteristic solder joint fatigue life with a value of 2,861 cycles.

This paper provides a comprehensive method to evaluate the reliability of solder joints in terms of physics and statistical‐based analysis.

The purpose of this paper is to establish the regression equation based upon a set of samples prepared through structured design of experiment and form a prediction model for prediction of the areal density gram per square meter (GSM) of the embroidered fabrics and study the influence of basic input parameters.

Embroidery samples are prepared taking input parameters as GSM of the base fabric, linear density of the embroidery thread and stitch density of the embroidery design. Three levels of values are identified for each of the input parameters. Taguchi and Box-Behnken experiment design principles are used to prepare two sets of samples. Linear multiple regression is used to determine the prediction equations based upon each of the two sets and the combined set as well. Prediction equations are statistically verified for the prediction accuracy. Also, surface curves are prepared to study the influence of embroidery parameters on the GSM.

It is found that all the three prediction models developed in this study can predict with a very satisfactory level of accuracy. However, the regression equation based upon the data set prepared according to Taguchi experiment design is emerged as the prediction model with highest level of prediction accuracy. Corresponding equation coefficients and several three-dimensional surface curves are used to study the influence of embroidery parameters and it is found that the stitch density is the most influential input parameter followed by stitch length and the GSM of base fabric.

This can be used to assess the GSM of embroidered fabrics before starting the actual embroidery process. So, this model can help the embroidery designers significantly to pre-estimate the GSM of the embroidered fabrics and select the design parameters accordingly. Also, this model can be a useful tool for estimation of thread consumption and thread cost in embroidery.

The input parameters used here are very basic parameters related to design and materials, which can be easily available. And also, a simple linear multiple regression is used to make the prediction equation simple and easy to use. So, this model can help the embroidery designers or garment designers to select/adjust the embroidery parameters and thread parameters accordingly in the planning and designing stage itself to ensure that the GSM of embroidered fabrics remains within desirable range. Also, this prediction model developed hereby may be a very useful tool for estimation of the consumption and cost of embroidery threads.

This paper presents a very fundamental study to reveal the effect of embroidery parameters on the GSM, through development of regression equations. It can help future researchers in optimizations of input parameters and forming a technical guideline for the embroidery designers for selection of the design parameters for a desired GSM of embroidered fabric.

The purpose of this study is to present the tool life optimization of carbide-coated ball nose milling inserts when high-speed milling of Inconel 718 under cryogenic CO₂ condition. The main aims are to analyze the influence level of each cutting parameter on the tool life and to identify the optimum parameters that can lengthen the tool life to the maximum.

The experimental layout was designed using Box–Behnken RSM where all parameters were arranged without combining their highest and lowest values of each factor at the same time. A total of 29 milling experiments were conducted. Then, a statistical analysis using ANOVA was conducted to identify the relationship between the controlled factors on tool life. After that, a predictive model was developed to predict the variation of tool life within the predetermined parameters.

Results from the experimental found that the longest tool life of 22.77 min was achieved at Vc: 120 m/min, fz: 0.2 mm/tooth, ap: 0.5 mm and ae: 0.2 mm. ANOVA suggests the tool life of 23.4 min can be reached at Vc: 120.06 m/min, fz: 0.15 mm/tooth, ap: 0.66 mm and ae: 0.53 mm. All four controlled factors have influenced the tool life with the feed rate and radial depth of cut (DOC) as the major contributors. The developed mathematical model accurately represented the tool life at an average error of 8.2 per cent when compared to the actual and predicted tool life.

These experimental and statistical studies were conducted using Box–Behnken RSM method under cryogenic CO₂ condition. It is a proven well-known method. However, the cooling method used in this study is a new technique and its effects on metal cutting, especially in the milling process of Inconel 718, has not yet been explored.

Toner is a crucial dry colorant composite used in printing based on the electrophotographic process. The quality of printed images is greatly influenced by the toner production method and material formulation. Chemically in situ polymerization methods are currently preferred. This paper aims to optimize the characteristics of a composite produced through emulsion polymerization using common raw materials for electrophotographic toner production.

Emulsion polymerization provides the possibility to optimize the physical and color properties of the final products. Response surface methodology (RSM) was used to optimize variables affecting particle size (PS), PS distribution (PSD), glass transition temperature (T_g°C), color properties (ΔE) and monomer conversion. Box–Behnken experimental design with three levels of styrene and butyl acrylate monomer ratios, carbon black pigment and sodium dodecyl sulfate surfactant was used for RSM optimization. Additionally, thermogravimetric analysis and surface morphology of composite particles were examined.

The results indicated that colorants with small PS, narrow PSDs, spherical shape morphology, acceptable thermal and color properties and a high percentage of conversion could be easily prepared by optimization of material parameters in this method. The anticipated outcome of the present inquiry holds promise as a guiding beacon toward the realization of electrographic toner of superior quality and exceptional efficacy, a vital factor for streamlined mass production.

To the best of the authors’ knowledge, for the first time, material parameters were evaluated to determine their impact on the characteristics of emulsion polymerized toner composites.

Environmental and operational restrictions increasingly drive modern aircraft design due to the growing impact of global warming on the ecology. Regulations and industrial measures are being introduced to make air traffic greener, including restrictions and environmental targets for aircraft design that increase aerodynamic efficiency. This study aims to maximize aerodynamic efficiency by identifying optimal values for sweep angle, taper ratio, twist angle and wing incidence angle parameters in wing design while keeping wing area and span constant.

Finding optimal wing values by using gradient-based and evolutionary algorithm methods is very time-consuming. Therefore, an artificial neural network-based surrogate model was developed. Computational fluid dynamics (CFD) analyses were carried out by using Reynolds-averaged Navier–Stokes equations to create a properly trained data set using a feedforward neural network.

The results showed how a wing could be optimized by using a CFD-based surrogate model. The two optimum results obtained resulted in increases of 10.7397% and 10.65% in the aerodynamic efficiency of the baseline design ONERA M6 wing.

The originality of this study lies in the combination of sweep angle, taper ratio, twist angle and wing incidence angle within the scope of wing optimization calculations.

The choice of best machining parameters is an extremely basic factor in handling of any machined parts. The purpose of this paper is to exhibit a multi-objective optimization technique; in view of weighted aggregate sum product assessment (WASPAS) technique toward upgrade the machining parameters in modified air abrasive jet machining (MAAJM) process: injecting pressure, stand-off distance (SOD), and abrasive mesh size measure with 100 rpm rotatable worktable on Nickel 233 alloy material. Three conflicting destinations, material removal rate (MRR), surface roughness (SR) and taper angles (Ta), respectively, are considered at the same time. The proposed procedure uses WASPAS, which is the examination of parametric optimization of the abrasive jet machining (AJM) process. The results was used any scopes of reactions in MAAJM process is the ideal setting of parameters are resolved through investigations represented. There is wide utilization of Nickel 233 in aviation enterprises; machining information on producing a hole utilizing MAAJM for the first time is given in this work, which will be helpful different industries.

This paper exhibits a multi-objective optimization technique; in view of WASPAS technique toward upgrade the machining parameters in MAAJM process: injecting pressure, SOD, and abrasive mesh size measure with 100 rpm rotatable worktable on Nickel 233 alloy material.

As an outcome of using the tool in any ranges of responses in the AJM process, the optimal setting of parameters is determined through experiments illustrated. The machining data of generating a hole using AJM are studied for the first time in this work, which will be useful for aerospace industries, where Nickel 233 is used broadly.

A new material in unconventional machining process and also a multi-objective optimization technique are adopted.

The present work is a systematic study to understand the cause of poor quality of sliver, roving and yarn due to defective sliver storage can-spring at finisher drawframe machine in spinning preparatory. This study aims to investigate the influence of can-spring stiffness factor, sliver deposition rate and sliver coils position on yarn unevenness and thin places considering two cases of sliver storage time.

Combed ring spun yarn samples were produced by varying finisher drawframe variables, which were can-spring stiffness, delivery speed and sliver coils position in storage can. For research design, three-factor three levels of Box-Behnken experimental design was adopted. To investigate the effect of sliver storage time on combed yarn unevenness and thin places, yarn samples were produced at 8 h sliver storage time and without allowing any storage time. Sliver storage time is the time for which combed drawn sliver kept idle in storage cans before feeding to speedframe machine. The 8 h sliver storage time was considered for present study after consulting industrial experts. Adequate numbers of the samples were tested for yarn quality parameters such as yarn unevenness and thin places 50 per cent/km on standard instruments. Finally, the test results were analyzed using statistical software to check the statistical significance of all the independent variables on observed response through analysis of variance.

The experimental results showed that the yarn samples produced from older can-springs and bottom position sliver coils stored at 8 h storage time were showing higher yarn unevenness and thin places compared to other yarn samples. The results also showed that the effect of delivery speed is not significant on yarn unevenness for samples produced without allowing any sliver storage time.

The present study is an outcome of a practical problem experienced at the finisher drawframe machine in a spinning industry. For this purpose, only scrutinized finisher drawframe variables were considered for the evaluation. There are many equally important other factors, which were not considered due to research work feasibility.

This paper investigates the effect of some imperative factors at the finisher drawframe stage on combed yarn quality. The present study will boost existing knowledge of the spinner’s community regarding the effect of can-spring stiffness, sliver coils position and storage time on resultant combed yarn quality parameters.

The work is original and only a few references are available. The study reveals that storage can-spring stiffness should be chosen carefully for better sliver handling. It is observed that finisher drawframe can-spring stiffness, sliver storage time and sliver coils position play a vital role in deciding quality characteristics of stored sliver and ultimately affect yarn quality.

The purpose of this paper is based on the response surface method, the authors determined the conditions for achieving the optimum rubber-sealing performance by using the maximum contact stress as the response value.

A two-dimensional model of a compression packer rubber was established by finite-element analysis software. Under the single axial load of 53.85 MPa, the four single factors of the end-face inclination angle, subthickness, height of rubber and friction coefficient of the rubber were analyzed.

Results show that the optimum sealing performance of the rubber tube is achieved when the end-face angle is equal to 45º and the thickness of the rubber tube is 9 mm. The response surface designed by Box–Behnken shows that the sealing performance of the rubber tube is the optimum when the end-face inclination angle is 48.1818°, the subthickness is 9 mm, the height of rubber is 90 mm and the friction coefficient is 0.1. Verification test results show that the model is reliable and effective.

Packer operations are performed downhole, and research on real experiments is limited. In this work, the feasibility of such experiments is determined by comparing finite-element modeling with actual experiments, and the results have guiding significance for actual downhole operations.

Surface roughness and vibration during machining are inevitable which critically affect the product quality characteristics. This paper aims to suggest the implementation of a multi-objective optimization technique to obtain the favorable parametric conditions which lead to minimum tool vibration and surface roughness of 6063-T6 aluminum alloy in computer numerically controlled (CNC) turning.

The case study has been accomplished according to response surface methodology RSM’s Box–Behnken design (BBD) matrix using Titanium Nitride-coated Tungsten Carbide insert in a dry environment. As the experimental results are quite nonlinear, a second-order regression model has been developed for the responses (surface roughness and tool vibration) in terms of input cutting parameters (spindle speed, feed rate and depth of cut). The goodness of fit of the models has also been verified with analysis of variance (ANOVA) results.

The significance efficacy of input parameters on surface roughness and tool vibrations has been illustrated through multi-objective overlaid 3D surface plots and contour plots. Finally, parametric optimization has been performed to get the desired response values under the umbrella of weighted aggregate sum product assessment (WASPAS) method and verified confidently with confirmatory test results.

The results of this study reveals that hybrid RSM with WASPAS method can be readily applicable to optimize multi-response problems in the manufacturing field with higher confidence.

The purpose of this study is to establish a suitable procedure for dyeing and multifunctional finishing on 100% cotton using extracts of eucalyptus leaves in an eco-friendly manner.

Box–Behnken design of experiments and analysis of variance (ANOVA) were used to optimise the conditions of extraction, dyeing and finishing. Phytochemical analysis was performed to determine the chemical constituents of the extracts. Colour strength, fastness properties were evaluated for dyed fabric samples. The effectiveness of eucalyptus leaves extract as an insect repellent, aroma, antibacterial finishing agent, was assessed. Pre-soaking and padding method was used for the application of active essential oil on the fabric.

Essential oil extracted from Eucalyptus globulus leaves have great repellent rate for insects to the extent of 90% and aroma intensity of 72% and antibacterial effect of 100% bacterial reduction up to five washings. The use of citric acid as cross-linking agent helps increase the durability of the finish. Natural dyeing to get light yellow shade is possible with extracts made with water, possessing good fastness properties.

Scaling up the extraction process and soaking larger quantities of fabrics in extracted essential oil solution before the pad applications are considered limitations of this study. However, smaller pieces of fabrics can conveniently be handled in this process. It has tremendous potential for practising industrially, to get yellow-shaded multifunctional finished cotton textiles.

Protection against insects, including mosquitoes, bacteria with additional aroma on cotton will be of great use in day-to-day life for the wearer.

Eco-friendly, renewable sources of ingredients from the plant were used to obtain protection against pathogenic or odour-causing microorganisms using this hygiene finish with multiple end uses.

This original work enables conducting dyeing and multifunctional finishing together in a single stage, which otherwise takes a number of steps, consuming large quantities of water, chemicals and energy to impart similar effects on cotton.