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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 optimization of a process requires exact knowledge of the process, which is knowledge of correlations and inter-dependence between the process-determining variables and the knowledge over the actual condition of the process. In a data rich knowledge poor process like spinning, where the exact relationships between machine, material, climate and quality are yet to be concluded objectively, this research focuses on the use of artificial neural networks as a tool to find out the correlations between decisive variables and to determine the optimum settings. Drawing frame is considered to be the last fault correction point in spinning preparation chain, therefore, its settings has a vital role to play towards yarn quality. Leveling action point is one of the important auto-leveling settings involving an automatic search function at Rieter drawing frame RSB-D40 and requiring a large amount of sliver. In this study, attempts were made to optimize the leveling action point. Optimization of draft settings is also within the scope of this article. The ANNs were used to achieve such objectives and they were found to be very helpful in identifying the optimum settings and hence decreasing material loss and improving sliver quality.

This study aims to investigate the effect of process parameters of blow room machines on openness degree and quality of cotton tufts in a blow room.

For this purpose, an experimental Box–Behnken design (BBD) was used, and the process parameters were the angles of the grid bars underneath the opening rollers of CVT3 beaters and the distance between feed roller of the first opening roller of CVT3.

It was found that the cotton tuft openness increased by increasing the angles of grid bars and by decreasing the distance between the feed roller and first opening roller on CVT3 beater. Further, the optimization procedure showed that an optimum value of cotton tuft openness (in laser method) was determined for specific levels of the process parameters.

The originality of this investigation is that it showed the individual effects and interactions of the most important factors in two tufting machines instead of only one machine. This study is important because it helps cotton yarn spinners to improve the quality of the final yarns by optimizing the levels of tuft openness which in turn improves fiber cleaning.

A new h‐refinement adaptive tetrahedral mesh generation algorithm is presented. Three‐dimensional domains, to be analysed by the finite element method, are initially modelled by a coarse background mesh of tetrahedral elements. This mesh forms the input for finite element analysis and error estimation by the Zienkiewicz‐Zhu simple error estimator. Adaptive mesh refinement proceeds by selecting an element for remeshing whose longest edge is shared by elements that also require refinement. This group of elements is refined by inserting a new node at the mid‐point of the shared edge thereby bisecting all elements within the group. Adaptive parameters are calculated for the new node and elements. Refinement then proceeds until no further group of elements can be found for refinement or no elements within the current mesh require further refinement. The shape quality of the current mesh is then enhanced by the iterative application of nodal relaxation plus three topological transformations. The entire refinement process is repeated iteratively until the required degree of mesh refinement is reached. Ten‐noded linear strain tetrahedral finite element meshes have been used for the finite element and error estimation analyses. Four examples of adaptive tetrahedral mesh generation for linear elastic stress/displacement analysis are presented which show that this algorithm is robust and efficient in terms of reduction of the domain error with a minimum number of degrees of freedom being generated, number of iterations, and therefore finite element analyses, required and computational time for refinement when compared to the advancing front method and Delaunay triangulation.

HISTORICAL. THE story of textile manufacture and the development of machinery designed to increase the production of yarns and cloths is an absorbing history. Although from the earliest times man has been master of the art of spinning and weaving, yet it is only during the last 200 years that any form of mechanisation has entered the industry.

The purpose of this paper is to analyze the relationship between the demographic characteristics of top management teams (TMTs) (i.e. age, gender, administrative level, senior management experience and educational background) and megaproject performance, with respect to schedule, cost, quality, safety and technological innovation. The results shed new light on the effectiveness of different types of TMT.

This paper collected secondary and objective data from 208 TMT members in 42 megaprojects and employed hierarchical regression analysis to test the research hypotheses.

The findings revealed that age has a significant influence on schedule performance; gender has a significant influence on safety performance; senior management experience has a significant influence on cost performance; and educational background has a significant influence on both schedule and technological innovation performance. However, this study did not find evidence of a significant relationship between the administrative level and megaproject performance.

This paper mainly focused on China’s megaprojects, most of which are globally influential (e.g. Hong Kong–Zhuhai–Macao Bridge and Shanghai Expo), however this sampling approach still limits the generalizability of research findings to other contexts.

The results of this paper contribute to a better understanding of how management team capabilities translate into better project achievements. This paper also provides implications on the criteria for selecting top megaproject managers to optimize the composition of the TMT and realize better performance.

The paper aims to provide an investigation about the effect of some selected production parameters such as core yarn type, sheath sliver type and total yarn count factors on core spun vortex yarns' evenness, imperfection and tensile properties. Hence it is aimed to contribute to the literature in vortex spinning where there are limited works related to core-spun vortex spinning.

The paper evaluates the effect of core yarn type, sheath sliver type and total yarn count factors on yarn evenness, imperfections, hairiness and tensile properties. Completely randomised three-factor analysis of variance (ANOVA) was conducted in order to evaluate the effect of core yarn type, sheath sliver type and linear yarn density on core spun vortex yarns' evenness, imperfection and tensile properties at significance level of 0.05. SNK tests were also performed for observing the means of each parameter. Correlation analysis was also conducted to reveal some relationships between yarn evenness and yarn tensile properties.

In this paper, significant factors related to some production parameters affecting the core-spun vortex yarns' evenness, imperfection, hairiness and tensile properties were found.

There are limited works related to effect of selected production parameters on yarn evenness, Imperfections and Tensile Properties of Hybrid Vortex Yarns.

Due to the excellent functionality of graphene, the research on fiber modification by graphene has been receiving more and more attentions recently, and many research findings have been conducted. However, the purpose of this paper is to focus on the fiber modification method and corresponding modified fiber properties, but the research on processing of the modified fiber, especially the textile process, is little. Therefore, in the paper, the properties of one kind of textile GN fiber and the spinning method of the GN fiber blend yarn and the functionalities of corresponding fabric are studied.

In the paper, the properties of nylon fiber modified by graphene (GN) were studied first. Then, according to the tested results, one new blending process of the GN fiber and cotton fiber was given, and corresponding properties of the blend yarns were tested and analyzed. Finally, the knitted fabrics were produced using the spun blend yarns, and the antibacterial property, electromagnetic shielding property, anti-ultraviolet performance, anti-static performance and conventional mechanical, and appearance thermal-wet comfort properties were tested and comparatively analyzed.

The tested results showed that the functionality of all fabrics was effective due to the addition of the graphene in the fiber, especially the antibacterial property. With the increasing of the GN fiber in the blend yarns, the functionality of all fabrics was also increased first and then achieved stability.

One new blending process of the GN fiber and cotton fiber was given. In the spinning, the combed cotton sliver was produced first, and then was torn into small parts of combed cotton sliver fiber by hand. Then, the treated GN fibers and cotton fibers were mixed for the first time, and corresponding GN/C carding sliver was produced. In this blend processing, the mixed cotton fiber was used to improve the sliver processing of the GN fiber. Then, in the drawing process, the required number of GN/C carding sliver and combed cotton sliver were fed simultaneously, and GN fibers and cotton fibers were mixed for the second time, and corresponding four kinds of GN/JC blend yarns were produced. In this blend processing, the mixed cotton fiber was used to regulate the blending ratio.

Inter-fibre cohesion is regarded as an important property of assemblies, such as slivers, made of wool or any other fibres, with respect to the processing in carding, drawing (gilling) and spinning. In this paper, the results of the multiple regression analyses, and their validation, are presented to show that a strong relationship exists between the sliver cohesion (measured as sliver tenacity and sliver specific energy-to-break in a long-gauge tensile test) and a combination of the standard wool properties, such as bulk, mean fibre length (Barbe), mean fibre diameter and medullation content, used for the objective blend specification of New Zealand wools for marketing and processing.

During steel plate and long-product production, numerous imperfections and defects appear that deteriorate product quality and consequently reduce revenue. The purpose of this paper is to provide a practical overview of typical defects (surface and internal) that occur and their root causes.

The data presented here derive from the quality department and from more than 50 technical reports of ELKEME S.A. on the last decade’s production of steel making companies STOMANA S.A. and SIDENOR S.A., with emphasis on the defects occurred in some of the products of the Bulgarian plant. Stereoscopic observations of surface defects, light optical metallography, and scanning electron microscopy with EDS represent the most used techniques to characterize defected macro-/micro-areas and microstructures.

In general, the most commonly encountered defects from semi-finished (billets, blooms, and slabs) and final (round bar and plate) steel products are as follows: network cracks, porosity, gas holes, shrinkage, shell, slivers, casting powder entrapment, ladle slag entrapment, other non-metallic inclusions, low hot ductility, centerline segregation cracking, macro- and micro-segregation, and mechanical defects (scratches, transverse cracks, and seams).

External and internal quality improvement can reduce the production cost (Euro/ton).

Improvement of the quality of industrial plates and long products increases the safety of the further-produced constructions and systems such as bridges, cranes, heavy equipment, automobile parts, etc.

Root cause analysis and categorization of the most commonly encountered defects can pave the way to production process improvements that directly affect final product quality and the overall per ton production cost. The benefits of this work obviously affect all steel producers/processers, and also society through the safety increase achieved by the quality improvement in the steel products used in constructions and automobile parts.