Use of Taguchi Method and Grey Relational Analysis to Optimize Multiple Yarn Characteristics in Open-End Rotor Spinning

Rotor speed and twist per metres (tpm) are two key parameters in open-end rotor spinning of cotton yarns. High spinning productivity can be obtained by keeping the rotor speed high and twist level as low as possible. However, too high rotor speed may result in yarn imperfections and too low twist level may result in lower tenacity yarns. This study aimed at optimising the multiple yarn characteristics in open-end rotor spinning using the Taguchi method and the grey relational analysis. Cotton yarn samples of 30 tex were produced on rotor spinning machine with different twist levels (i.e. 500, 550, 600 and 700 tpm) at different rotor speeds (i.e. 70,000, 80,000, 90,000 and 100,000 rpm) according to the Taguchi design of experiment. Optimal spinning process parameters were determined using the grey relational grade as the performance index. It was concluded that for the cotton fibres and yarn count used in this study, optimum properties of the yarns could be obtained at 90,000 rpm rotor speed and 700 tpm

Statistical Modeling for the Effect of Rotor Speed, Yarn Twist and Linear Density on Production and Quality Characteristics of Rotor Spun Yarn

The aim of this study was to develop a statistical model for the effect of RS (Rotor Speed), YT (Yarn Twist) and YLD (Yarn Linear Density) on production and quality characteristics of rotor spun yarn. Cotton yarns of 30, 35 and 40 tex were produced on rotor spinning machine at different rotor speeds (i.e. 70000, 80000, 90000 and 100000 rpm) and with different twist levels (i.e. 450, 500, 550, 600 and 700 tpm). Yarn production (g/hr) and quality characteristics were determined for all the experiments. Based on the results, models were developed using response surface regression on MINITAB�16 statistical tool. The developed models not only characterize the intricate relationships among the factors but may also be used to predict the yarn production and quality characteristics at any level of factors within the range of experimental values

An environmentally friendly process for the preparation of UHMWPE As-Spun fibres

The extrusion of ultra high molecular weight polyethylene (UHMWPE) fibres cannot be achieved by conventional extrusion processes due to its very high melt viscosity. To overcome this limitation, UHMWPE is first dissolved in a petrochemical to form a gel before extrusion. The petrochemicals used to dissolve the polymer then need to be removed using other chemicals making the process unfriendly to the environment. This article is focused on finding an environmentally friendly, natural solution to replace these chemicals and altering the process to potentially reduce the process cost

Water-pipe smoking and metabolic syndrome: a population-based study.

Water-pipe (WP) smoking has significantly increased in the last decade worldwide. Compelling evidence suggests that the toxicants in WP smoke are similar to that of cigarette smoke. The WP smoking in a single session could have acute harmful health effects even worse than cigarette smoking. However, there is no evidence as such on long term WP smoking and its impact on chronic health conditions particularly cardiovascular and metabolic conditions. Therefore, we conducted this study to investigate the relationship between WP smoking and metabolic syndrome (MetS). This was a cross-sectional study carried out in Punjab province of Pakistan using the baseline data of a population-based study--Urban Rural Chronic Diseases Study (URCDS). Information was collected by trained nurses regarding the socio-demographic profile, lifestyle factors including WP smoking, current and past illnesses. A blood sample was obtained for measurement of complete blood count, lipid profile and fasting glucose level. MetS was ascertained by using the International Diabetic Federation's criteria. We carried out multiple logistic regressions to investigate the association between WP smoking and MetS. Final sample included 2,032 individuals--of those 325 (16.0%) were current WP smokers. Age adjusted-prevalence of MetS was significantly higher among current WP smokers (33.1%) compared with non-smokers (14.8%). Water-pipe smokers were three times more likely to have MetS (OR 3.21, 95% CI 2.38-4.33) compared with non-smokers after adjustment for age, sex and social class. WP smokers were significantly more likely to have hypertriglyceridemia (OR 1.63, 95% CI 1.25-2.10), hyperglycaemia (OR 1.82, 95% CI 1.37-2.41), Hypertension (OR 1.95, 95% CI 1.51-2.51) and abdominal obesity (OR 1.93, 95% CI 1.52-2.45). However, there were no significant differences in HDL level between WP smokers and non-smokers. This study suggests that WP smoking has a significant positive (harmful) relationship with MetS and its components

Relationship between water-pipe smoking and metabolic syndrome.

<p>Multivariate models include all co-variates presented in the table.</p

Relationship between water-pipe smoking and components of metabolic syndrome.

<p>All estimates were adjusted for age at screening, social class and area of residence. * indicate increased level of specific measure or a previously diagnosed condition.</p