Manoj Kumar Imrith, Satyadev Rosunee and Roshan Unmar
The thermophysiological comfort of fabrics is prerequisite as customers covet adequate moisture, heat management-supported and UV protective clothing that measure up to their…
Abstract
Purpose
The thermophysiological comfort of fabrics is prerequisite as customers covet adequate moisture, heat management-supported and UV protective clothing that measure up to their levels of activities and environmental conditions. Hitherto, scant tasks have been reported with the purpose of engineering both comfort and UV protection simultaneously. From that vantage point, the objective of this work is to develop a model for optimum UPF, air permeability, water-vapour resistance, thermal resistance, thermal absorptivity and areal density of knitted fabrics.
Design/methodology/approach
Weft knitted fabrics of various compositions were investigated. UPF was tested using the Labsphere UV transmittance analyser. The FX 3300 (Textest instruments) air permeability tester was used to test air permeability. Thermal comfort and water-vapour resistance were evaluated using the Alambeta and Permetest instruments, respectively. Based on image processing, the porosity was measured. Fabrics thickness and areal density were measured according to standard methods. Furthermore, parametric and non-parametric statistical test methods were applied to the data for analysis.
Findings
Linear regression was substantiated by Kolmogorov-Smirnov test. Then multiple linear regression of porosity and thickness together on UPF and comfort parameters were visually depicted by virtue of 3D linear plots. Residual analysis with quantile-quantile and probability plots, advocated the tests using the Shapiro-Wilk test. The result was validated by comparison with experimental data tested. The samples gave satisfactory relative errors and were supported by the z-test method. All tests indicated failure to reject the null hypothesis.
Originality/value
The predictive models were embedded into an interactive computer program. Fabric thickness and porosity are the inputs needed to run the program. It will predict the optimum UPF, areal density and thermophysiological comfort parameters. In a nutshell, knitters may use the program to determine optimum structural parameters for diverse permutations of UPF and thermophysiological comfort parameters; scilicet high UV protection together with low thermal insulation combined with low water-vapour resistance and high air permeability.
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Bahadur Goonesh Kumar, Satyadev Rosunee and Mark Bradshaw
In this research project, electrical conductive yarns were knitted together with 100 per cent cotton yarns to create knitted fabrics that would be used as electromagnetic (EM…
Abstract
Purpose
In this research project, electrical conductive yarns were knitted together with 100 per cent cotton yarns to create knitted fabrics that would be used as electromagnetic (EM) shielding materials. The paper aims to discuss these issues.
Design/methodology/approach
1×1 plain fabrics knitted on double-bed hand knitting machines of five and seven gauges. Several strands of the cotton yarns were used together in order to knit samples with good handling properties. The electrical conductive yarn has six plies and each ply has 29 filaments with Naño-coating of silver and having an electrical resistance of 4 Ohms per 100 mm and a count of 96 Tex. The knitted fabrics have similar texture but vary in term of specific weight, fabric density, loop length, Tex, tightness factor, thickness and electrical conductivity. These variations affected the properties of the fabrics, determining factors of a good shielding or not. A special designed Faraday cage was built to measure the EMSE of each knitted fabrics. The EM waves were sent through the signal generator at different frequencies as from 400 to 1,100 MHz and with three different power inputs of 10, 20 and 30 dBm. EMSE measurements were also carried out after the knitted samples were rotated clockwise.
Findings
Good EMSE shielding results were achieved with the knitted samples, however in this study it was found that different knitted fabrics shielded better at specific frequencies and power inputs.
Practical implications
Knitted fabrics can be used to develop comfortable garments that can be used to shield EM waves and protect the wearer.
Originality/value
The choice of using the conductive yarns is exclusive. In addition the EMSE were measured with fabrics knitted in the same structure but on different knitting machine gauge. Three different power inputs were considered and EMSE measurements were taken using frequencies as from 400 to 1,100 MHz. A new method for measuring the electrical resistance on the knitted fabrics and the method used for measuring the EMSE for each knitted fabric were considered.
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Manoj Kumar Imrith, Satyadev Rosunee and Roshan Unmar
Lightweight, open construction cotton knitted fabrics generally do not impart good protection from solar ultraviolet radiation (UVR). As lightweight 100% cotton single jersey is…
Abstract
Purpose
Lightweight, open construction cotton knitted fabrics generally do not impart good protection from solar ultraviolet radiation (UVR). As lightweight 100% cotton single jersey is highly cherished for summerwear, it is sine qua non to understand the structural parameters that effectively strike a good balance between UV protection and thermophysiological comfort of the wearer. Relatively heavy fabrics protect from UVR, but comfort is compromised because of waning porosity, increase in thickness and thermal insulation. The purpose of this paper is to engineer knits that will bestow maximum UV protection while preserving the thermophysiological comfort of the wearer.
Design/methodology/approach
In total, 27 cotton single jersey fabrics with different areal densities and yarn counts were selected. Ultraviolet protection factor (UPF) was calculated based on the work of Imrith (2022). To précis, the authors constructed a UV box to measure the UPF of fabrics, denoted as UPFB. UPFB data were correlated with AATCC 183-2004 and yielded high correlation, R2 0.977. It was concluded that UPF 50 corresponds to UPFB 94.3. Thermal comfort properties were measured on the Alambeta and water-vapour resistance on the Permetest. Linear programming (LP) was used to optimize UPFB and comfort. Linear optimization focused on maximizing UPFB while keeping the thermophysiological comfort and areal density as constraints.
Findings
The resulting linear geometrical and sensitivity analyses generated multiple technically feasible solutions of fabrics thickness and porosity that gave valid UPFB, thermal absorptivity and water-vapour and thermal resistance. Subsequently, an interactive optimization software was developed to predict the stitch length, tightness factor and yarn count for optimum UPFB from a given areal density. The predicted values were then used to knit seven 100% cotton single jersey fabrics and were tested for UV protection. All seven fabrics gave UPFB above the threshold, that is, higher than 94.3. The mathematical model demonstrated good correlations with the optimized parameters and experimental values.
Originality/value
The optimization software predicted the optimum UPFB reasonably well, starting from the fabric structural and constructional parameters. In addition, the models were developed as interactive user interfaces, which can be used by knitted fabric developers to engineer cotton knits for maximizing UV protection without compromising thermophysiological comfort. It has been demonstrated that LP is an efficient tool for the optimization and prediction of targeted knitted fabrics parameters.
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Tulsi Pawan Fowdur, Satyadev Rosunee, Robert T. F. Ah King, Pratima Jeetah and Mahendra Gooroochurn
In this chapter, a general introduction on artificial intelligence (AI) is given as well as an overview of the advances of AI in different engineering disciplines, including its…
Abstract
In this chapter, a general introduction on artificial intelligence (AI) is given as well as an overview of the advances of AI in different engineering disciplines, including its effectiveness in driving the United Nations Sustainable Development Goals (UN SDGs). This chapter begins with some fundamental definitions and concepts on AI and machine learning (ML) followed by a classification of the different categories of ML algorithms. After that, a general overview of the impact which different engineering disciplines such as Civil, Chemical, Mechanical, Electrical and Telecommunications Engineering have on the UN SDGs is given. The application of AI and ML to enhance the processes in these different engineering disciplines is also briefly explained. This chapter concludes with a brief description of the UN SDGs and how AI can positively impact the attainment of these goals by the target year of 2030.
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Jaykumar Chummun and Satyadev Rosunee
The tourist sector in Mauritius is aiming at welcoming 2 million tourists by the year 2015 and coming up with creative ideas and products branded with ‘Made in Mauritius’ to boost…
Abstract
The tourist sector in Mauritius is aiming at welcoming 2 million tourists by the year 2015 and coming up with creative ideas and products branded with ‘Made in Mauritius’ to boost the country’s craft sector. This project looks into the manufacture of paper-yarn. Different types of paper were cut into ribbons of varying widths and converted into yarn by two methods: twisting and folding. The folds were made along the axis of a ribbon while twisting required prior moistening and was carried out on a modified yarn-twist measuring device. The relationship between the number of folds/twists and the strength of the resulting paper yarn was investigated. Yarn of high quality can be obtained by twisting ribbons of relatively smaller widths or folding relatively wider ribbons. The yarn can be used for manufacturing craft products.
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This paper describes the colouration of wool with indigo. The wool fabric is pre-treated with different shrink-resist formulations followed by application of indigo. The novel…
Abstract
This paper describes the colouration of wool with indigo. The wool fabric is pre-treated with different shrink-resist formulations followed by application of indigo. The novel dyeing procedure has resulted in commercially acceptable indigo-dyed wool, in terms of improved levelness and reduced yellowness.
While indigo is traditionally applied by the padding technique, in the present work, an exhaust dyeing procedure is investigated. The degree of levellness and the depth of shade are further optimised by varying the pH, temperature and dye concentration. The pH of the dye liquor and the dyeing temperature are found to be critical in achieving level dyeing as well as mitigating fibre damage.
It is found that certain shrink-resist formulations, either applied alone or in combination, give better results in terms of colour yield and fabric handle, while other combinations give poorer results. The dyed samples are found to exhibit excellent wash fastness.
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Sheraz Hussain Siddique Hussain Yousfani, Salma Farooq, Quratulain Mohtashim and Hugh Gong
Porosity is one of the most important properties of the textile substrate. It can influence the comfort of a garment by affecting its breathability and thermal conductivity…
Abstract
Purpose
Porosity is one of the most important properties of the textile substrate. It can influence the comfort of a garment by affecting its breathability and thermal conductivity. During the process of dyeing, the dye liquor comes in contact with the substrate; the absorption of the dye liquor into the substrate will be dependent on its porosity. The concept of porosity between the yarns of fabric is a common phenomenon; however, the porosity between the fibres in the yarn can also influence the dyeing behaviour of the fabric.
Design/methodology/approach
In this research, ring and rotor yarns of 25/s and 30/s counts are considered as textile substrates. The porosity of yarns was determined theoretically and experimentally using the image analysis method.
Findings
It was found that theoretical porosity is independent of the yarn manufacturing method. In addition, 30/s yarn was more porous as compared with 25/s yarn having a higher pore area. Rotor yarns had higher porosity, dye fixation and K/S as compared with ring yarns. Dyeing behaviour was also dependent on the count of yarn. Specifically, 30/s yarns have higher dye fixation as compared with 25/s yarns. However, 25/s yarns were dyed with deeper shades showing higher K/S values. Also, 25/s yarns are coarser than 30/s yarns having higher diameters and cross-sectional area, thus resulting in deeper shades and higher K/S values.
Originality/value
This novel technique is based on the comparative study of the porosity of various types of yarns using the image analysis technique. This investigation shows that the porosity between the fibres in the yarn can also influence the dyeing behaviour of the yarn.
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Sofien Benltoufa, Hind Algamdy, Adel Ghith, Faten Fayala and Lubos Hes
The paper aims to investigate the dynamic measurement of the water vapour resistance. The water vapour diffusion kinetics depends on the fibre’s material. So, water vapour…
Abstract
Purpose
The paper aims to investigate the dynamic measurement of the water vapour resistance. The water vapour diffusion kinetics depends on the fibre’s material. So, water vapour resistance measurement times till the equilibrium steady state can vary in the case of natural fibres compared to synthetic fibres. Devices for determining water vapour resistance according to the ISO 11092 standard allow static values to be measured.
Design/methodology/approach
In this study to investigate the dynamic of the water vapour resistance, a new parameter named “holding period” was introduced and defined as the time from sample placement on the measuring head until the measuring process begins. The holding period was varied as 0, 30, 60, 90, 120, 180, 240 and 300 s. Wool and cotton knitted fabrics were tested as natural fibres and compared to 100% polyester and 90% polyester/10% elastane as synthetic fibres. Measurements were conducted under both air velocities of 1 and 2 m/s. The experimental test data were statistically analysed based on ANOVA and four-in-one residual plots.
Findings
Statistical analysis of experimental tests shows that the holding period affects water vapour resistance in both air velocities of 1 and 2 m/s and on the measured values in the case of hydrophilic fibres.
Research limitations/implications
The study of the dynamic relative water vapour permeability of natural and synthetic is an important area of interest for future research.
Practical implications
It is recommended to hold the samples on the top of the head measurement before starting the test.
Originality/value
Following the ISO 11092 standard, the static values of the water vapour resistance were measured without considering the dynamic behaviour of the water vapour diffusion through the textile fabrics. This paper fulfils an experimental dynamic measurement of the water vapour resistance.
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Jeynakshi Ladsawut and Tasneem Mustun
Through analysis and discussion of the case study, students should be able to understand the marketing mix concept in the context of the retail industry, analyse how the adoption…
Abstract
Learning outcomes
Through analysis and discussion of the case study, students should be able to understand the marketing mix concept in the context of the retail industry, analyse how the adoption of new media such as social media transforms the elements of the marketing mix and evaluate the marketing mix strategies and their influence on future buying behaviours.
Case overview/synopsis
Founded in 2012, “Gecko Kids” is a designer clothing brand based in Mauritius, renowned for its vibrant and playful designs catering to children's fashion and lifestyle. Inspired by the lively spirit of Mauritius, Gecko Kids offers a diverse range of clothing and accessories designed to ignite children's imaginations and celebrate their sense of adventure. In addition to its captivating designs, Gecko Kids, under the leadership of its lead designer, Varnee Moodely, is committed to sustainability, using organic and ethically sourced materials wherever possible. Through responsible manufacturing processes and partnerships with local artisans, the brand strives to minimise its environmental footprint while supporting the communities that inspire its creations. After 32 years in operation, the brand finds itself struggling with challenges stemming from its current marketing mix strategy. This case study delves into the brand’s struggles across the 4Ps – product, price, place and promotion – and explores potential solutions, especially in the 21st century where most companies are adopting digital marketing strategies. Can the company rectify the repercussions of an inadequate marketing plan to sustain the Gecko Kids brand as a thriving local Mauritian entity?
Complexity academic level
This case study is suitable for undergraduate-level programmes in marketing.
Supplementary materials
Teaching notes are available for educators only.
Subject code
CSS 8: Marketing.