ORIGINAL_ARTICLE
Parameter Estimation of Viscoelastic Model to Simulate the Compression Behavior of Artificial Grass under Dynamic Loading Using Imperialist Competitive Algorithm
In this study, the parameters of linear Jeffrey’smodel are estimated using imperialist competitive algorithmto simulate the compression behavior of artificial grass underdynamic loading. To this end, a viscoelastic model is usedto explain this behavior according to ISO 2094. The modelconsists of a linear spring and a dashpot set parallel to eachother. This combination is placed in series with a linear dashpot.The Fourier transform periodic excitation is converted to thesummation of harmonic forces. Then, differential equations ofthe system motion are solved analytically. The result predictedfor the compression behavior of artificial grass in dynamicloading is compared with the experimental results. Accordingto the results, the average value of error for prediction of thecompression behavior is 5.68%. Therefore, the linear JeffreyʼsII model has a high ability to predict the compression behaviorof artificial grass under dynamic loading.
http://www.itast.ir/article_126730_74208fe16f706e703501f60ecbc7dec5.pdf
2021-01-01
1
12
ORIGINAL_ARTICLE
Study on Breast Shape Changing in Various Body Positions Using Depth Camera13
In this research, 3D scan based on depth camerais used to measure, and analyze the breast shape changesin various body positions. 3D breast shapes of women areextracted from data obtained from a depth camera. Ameasurement method is developed based on cross sectionlines to get the 2D breast pattern. 3D breast shape and 2Dbreast patterns in five body positions are determined andcompared to each other. To calculate the difference, 3Dbreast form and volume, also area and form of 2D breastpattern are measured. The results show that the breastform and volume in various body positions is not the same.Women have the highest volume and area of breast in theposition ‘posture of 45 elbow-bend and arms to the back’subsequent the position ‘posture of 45 elbow-bend andarms to the front’, ‘lower arm beside the body ‘ and ‘raisearm overhead and holding on the brow’, respectively. Alsoin the position ‘holding arm overhead’ the lowest volumeof breast for women is observed. The difference of breastvolume in the largest and smallest shape is about 23%. Thecombination of measuring breast volume and form at thesame time can provide effective information for bra cup design.
http://www.itast.ir/article_126731_4abc20f93016d2c55f961ddbc499a48a.pdf
2021-01-01
13
26
ORIGINAL_ARTICLE
Modeling and Optimization of Colloidal Nanosilver Pretreatment on Acid-Free Dyeing, Antibacterial, and Hydrophilicity of Polyamide-6,6 Using Response Surface Methodology
Enhancement of dyeability, antibacterial, andhydrophilicity of polyamide-6,6 was introduced with colloidalsilver nanoparticles (CSNs) and butane tetra carboxylic acid(BTCA) using cubic statistical models. Different concentrationsof CSNs and BTCA were investigated to evaluate theirinfluences on dyeability, antibacterial, hydrophilicity, andcolor change properties of polyamide-6,6 fabric by applyingstatistical design of D-optimal method. Antibacterial propertyof treated sample was tested by Gram-negative bacteriumEscherichia coli and Gram-positive bacterium Staphylococcusaureus. To achieve optimum conditions for polyamide-6,6,response surface methodology was also utilized. Here, CSNswere stabilized on polyamide-6,6 surface using BTCA ascrosslinking agent in order to enhance washing durability.Scanning electron microscopy and energy-dispersivespectroscopy were employed to characterize presence of CSNson surface of polyamide-6,6 and elemental composition oftreated polyamide-6,6 fabrics. Treatment optimization led toconsiderably absorption enhancement of C.I. Acid Red 81 dyethrough cubic statistical models on polyamide-6,6 surfaces aswell as antibacterial and hydrophilicity characteristics andminimized color change caused due to CSNs influence. Theprincipal result is synergetic effect utilizing BTCA accompanywith CSNs on enhancing and durability of mentionedproperties quantitatively in optimized conditions. Overall,the suggested method could be introduced as a new route,disclosing various desirable multifunctional characteristics topolyamide-6,6 fabric.
http://www.itast.ir/article_126732_6e1ad682eac3832a90980938836ded98.pdf
2021-01-01
27
40
ORIGINAL_ARTICLE
Effect of Seam Stabilizing Tapes on the Recovery Properties of Sewn Fabrics
Maintaining and improving the garment qualityare the important topics in the textile and apparel industry.The aim of this paper is to investigate the influence of sometextile tapes on elastic properties as well as dynamic recoveryof the seams and enhance the shape stability. Three sampleswere prepared, namely weft knitted sewn fabrics without anystabilizing tape, and weft knitted sewn fabrics stabilized withbias woven fabric, and with stretch ribbons. The results showthat hysteresis area of the seam tensile curves decreased byincreasing the loading cycles, and dynamic work recoverystabilized after the third cycle. The tensile stress of all sewnsamples in the course direction is significantly less than thestress value in the wale direction. It is found that the seamsstabilized with stretch ribbons have the highest dynamicwork recovery (~40-70%). Also, when the seam position andthe loading direction aligned, the dynamic work recovery ofthe stabilized samples increased. The recovery behavior ofthe stabilized sewn fabrics was also simulated by mechanicalmodels consisting of spring and dashpot elements. The threeelementmodel, consisting of the Maxwell body paralleledwith a non-linear spring, properly estimated the force–straincurves of the stabilized sewn fabrics under cyclic loading.
http://www.itast.ir/article_126733_a951835a551ce7a727eab40dc9f3a1eb.pdf
2021-01-01
41
50
ORIGINAL_ARTICLE
Effect of Brand Image and Interior Design of Sportswear Retailers on Loyalty: A Statistical Approach
This paper examines the impact of interior designand brand image on repurchasing and customer loyalty forsportswear products. In doing so, stratified sampling of targetmarkets is considered for data gathering. In this respect,we apply C-means clustering technique regarding crucialattributes affecting customers’ market of sportswear. The dataare collected using a self-administered questionnaire fromrespondents belonging to the resultant clustered market. Wemake the most of factor loads and t-test analysis to investigatethe proposed conceptual model. Moreover, this study isperformed by using SPSS to verify the reliability, and validityof the measured variables. Hypothesis tests are done utilizingstructural equation model (SEM) as a statistical method. Theresults of this paper indicate the significant relations amonginterior design, brand image and customer loyalty. Finally, onewayand two-way analyses of variance (ANOVA) are conductedin order to clarify dependency of findings to demographicalvariables.
http://www.itast.ir/article_126734_aff7de42b10343886b0781e31a41cdec.pdf
2021-01-01
51
64
ORIGINAL_ARTICLE
Investigation on Physical and Mechanical Properties of Denim Woven Fabrics Made from Different Spandex Percentages
The main topic investigated in this paper is theanalysis of the effect of different spandex percentages onphysical and mechanical properties of the denim fabric. Theresults showed that percentage of elastane has a significanteffect on the physical and mechanical properties of cotton/elastane woven denim fabric. The influence of variouselastane percentages via the above denim fabric performanceparameters is investigated by employing a one-way analysisof variance (ANOVA) statistical software package. Tensilestrength of denim fabric decreases as the percentage of theelastane increases because of the lower tenacity of spandexfibers compared to cotton fibers. Fabric breaking elongationincreases as spandex percentage increases. The tear strengthof denim fabric decreases as elastane percentage increases. Asspandex percentage increased, the fabric contraction of thewoven fabric increased, which made the fabric more compactand bulk, resulting in higher fabric thickness, fabric weight,and deep shade color. In addition, fabric stretchability andfabric elastic recovery increase with spandex percentage sinceelastane has higher stretch and makes the structure morecompact, but fabric growth decreases as spandex percentageincreases, due to the rather high recovery properties ofspandex. The obtained results showed that Lycra proportioninside fabric has an effect on the fabric tensile strength,breaking extension, tear strength, stretchability, fabricthickness, GSM, and fabric shade color.
http://www.itast.ir/article_126735_569503bbec9ec666eaa489297049c4d5.pdf
2021-01-01
65
75