Search results

1 – 10 of over 52000
Article
Publication date: 10 August 2010

Gulcan Ozkan and Recep Eren

The purpose of this paper is to investigate warp and weft crimp distribution over the fabric width and how it is influenced by warp tension distribution over the warp width.

Abstract

Purpose

The purpose of this paper is to investigate warp and weft crimp distribution over the fabric width and how it is influenced by warp tension distribution over the warp width.

Design/methodology/approach

An experimental design in this research includes air jet loom, tension sensor, inductive sensor and personal computer.

Findings

It is found that warp crimp in the fabric on the loom is higher in the edge zones than the middle of the fabric and warp crimp in the middle is higher than warp crimp in edge zones of the grey fabric. Weft crimp in the edge zones is higher than in the middle of the grey fabric. The reason behind warp tension and warp and weft crimp variations over fabric width is that weft yarn slips towards inside fabric at selvedges and gets relaxed during beat up.

Originality/value

It is proved that reducing weft yarn slip and therefore weft yarn relaxation during beat up will reduce warp tension and warp and weft crimp variations and improve the uniformity of fabric properties over the fabric width.

Details

International Journal of Clothing Science and Technology, vol. 22 no. 4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 June 2001

Darja Žunič‐Lojen and Jelka Geršak

The perfect interlacing of needle and bobbin thread in the stitch formation process and seam appearance depends first of all on correct pre‐tension of the tension

Abstract

The perfect interlacing of needle and bobbin thread in the stitch formation process and seam appearance depends first of all on correct pre‐tension of the tension regulator. Changes in the pre‐tension settings also have a direct influence on the tensile force during the sewing process. This contribution presents the influence of pre‐tension in a defined area on the tensile force in important phases of the stitch formation process. In addition the influence of the stitch velocity on tensile force was investigated. On the basis of statistic analysis it was ascertained in which pre‐tension area and stitch velocity the significant differences between tensile forces occurred.

Details

International Journal of Clothing Science and Technology, vol. 13 no. 3/4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 March 1994

F.B.N. Ferreira, S.C. Harlock and P. Grosberg

A study of thread tensions on a lockstitch sewing machine was made, measuring simultaneously both the needle and bobbin thread tensions. Experiments were carried out under…

537

Abstract

A study of thread tensions on a lockstitch sewing machine was made, measuring simultaneously both the needle and bobbin thread tensions. Experiments were carried out under specified sewing conditions, whereby needle and bobbin thread tensioner adjustment, sewing speed, number of plies, fabric quality and sewing thread quality were varied in order to investigate the effect of these factors on the needle and bobbin thread tensions. The patterns of the thread tension traces obtained were analysed as well as the effect of these factors on the peak tensions detected on both thread tension traces. Four significant peak tensions on the needle thread tension trace and two significant peak tensions on the bobbin thread tension trace were detected, during a stitch cycle. It was found that no significant variations occurred as far as the timing and shape of the peak tensions were concerned. However, variations were detected in the peak tensions according to the sewing conditions, as expected. From the analysis of the data obtained, multiple regression equations were derived to predict, with a good degree of accuracy, the peak tensions generated, according to the sewing conditions.

Details

International Journal of Clothing Science and Technology, vol. 6 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 June 1952

W.A.P. Fisher, R.H. Cross and G.M. Norris

The prevention of fatigue in bolts by controlled pre‐tensioning is investigated theoretically. It is shown that the effect of pre‐tension is to reduce the alternating load…

Abstract

The prevention of fatigue in bolts by controlled pre‐tensioning is investigated theoretically. It is shown that the effect of pre‐tension is to reduce the alternating load in the bolt and that the stiffness of the fitting plays an important part in this reduction. Fatigue tests on ¾‐in. B.S.F. bolts with various amounts of pre‐tension show how this reduction in alternating load can prevent fatigue failure. A warning is given against relying on the benefits of pre‐tensioning without ensuring that pre‐tension is maintained in service.

Details

Aircraft Engineering and Aerospace Technology, vol. 24 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 1995

Victor P. Janule

Formulators must control coating transfer and adhesion by developing formulations that perform well under widely varying application speeds and operating conditions. There…

Abstract

Formulators must control coating transfer and adhesion by developing formulations that perform well under widely varying application speeds and operating conditions. There are factors that can be controlled, and others that cannot be controlled. It is especially useful, and often essential, for the formulator to have an understanding of the principles and relationships of surface and interfacial tension, and surface energy or “wetting tension”. A review of these important principals and relationships, with a brief introduction to formulation variables sets the stage for introduction of an instrument that can easily measure the surface tension of coatings and the wetting tension of the surfaces or “substrates” to be coated.

Details

Pigment & Resin Technology, vol. 24 no. 1
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 August 2015

E.A.S.K. Fernando and T.S.S. Jayawardana

The tension variations across the width of the weaver's beam cause uneven tension in the fabric formation zone. As a result of the tension variation, the woven fabric…

Abstract

The tension variations across the width of the weaver's beam cause uneven tension in the fabric formation zone. As a result of the tension variation, the woven fabric tends to have fabric defects, such as non-uniform fabric density and differential dye take–up at various places on the fabric. As the warp ends are continuously subjected to varying tensions, warp breakage frequently occurs. As a result, the quality of the fabric produced suffers and there is reduced loom efficiency. However, uniformity in the fabric density is crucial, especially for technical and smart textiles. In this paper, the authors have attempted to model the varyingtensions across different segments of a warp sheet under a set of assumptions and derived a linear model. Furthermore, a prototype of an automatic tension control device is instrumentedwith two different positions which are located one meter apart and allows the tension variations across the warp-sheet to be practically observed. The measured average tension shows that variations in the internal tension on different segments of the warp-sheet can be minimized or even completely eliminated over time. With the implementation of a related experiment, the authors have shown the effectiveness of this automatic tension controller and its strong implications for the industry.

Details

Research Journal of Textile and Apparel, vol. 19 no. 3
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 1 June 2015

Xinjin Liu, Xuzhong Su and Hong Zhang

Spinning triangle is a critical region in the spinning process of staple yarn, which geometry influences the distribution of fiber tension and determines the qualities of…

Abstract

Purpose

Spinning triangle is a critical region in the spinning process of staple yarn, which geometry influences the distribution of fiber tension and determines the qualities of yarn directly. Therefore, the purpose of this paper is to investigate the fiber tension distribution at the twist point.

Design/methodology/approach

First, one theoretical model of fiber tension distributions at the twist point is given according to the motion law of fibers in the spinning triangle. Then, one calculation method of fiber tension at the twist point is given by two steps. First, the initial tension of each fiber at the front nip line caused by the yarn load should be calculated according to the models obtained based on the principle of minimum potential energy. Second, the fiber tensions at the twist point can be calculated using the obtained model in this paper. Finally, as an application of the proposed method, spinning triangles of a modified ring spinning system with a pair of offset device which can change the horizontal offset of the twist point to the symmetric axis of nip line of the spinning triangle continuously are studied. The fiber tension distributions are simulated numerically.

Findings

It is shown that the fiber tension distributions at the twist point can be determined by fiber feeding into and out the spinning triangle speed, the initial tension of each fiber at the front nip line, fiber tensile Young’s modulus and cross-sectional area, the number of fibers at spinning triangle and the individual fiber angle with the center fiber. The spinning experiment shows that taking appropriate right or left offset of the spinning triangle can help to improve the spun yarn qualities.

Originality/value

In this paper, the fiber tension distribution at the twist point is investigated. One theoretical model of fiber tension distributions at the twist point is given according to the motion law of fibers in the spinning triangle first. Then, one calculation method of fiber tension at the twist point has been given under the assumption that the initial tension of each fiber at the front nip line is caused by the yarn load.

Details

International Journal of Clothing Science and Technology, vol. 27 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 6 September 2022

Allan Discua Cruz, Jose Mario Reyes Hernandez and Carlos Roberto Arias Arévalo

This study aims to focus on understanding the tensions experienced by government officials in introducing electronic government (e-government) policies to support…

Abstract

Purpose

This study aims to focus on understanding the tensions experienced by government officials in introducing electronic government (e-government) policies to support entrepreneurs in a developing Latin American country.

Design/methodology/approach

This study relies on an in-depth qualitative approach based on collaborative and analytic auto-ethnography. The authors concentrate on tensions experienced by a government official and how they were addressed when introducing e-government policies to support entrepreneurs during the Covid-19 pandemic.

Findings

The findings reveal that paradoxical tensions occur as changes are demanded, multiple concerns are expressed and decisions about resources have to be made. The findings reveal sources of tensions from government, business and external sources. Addressing such tensions revolves around a diverse form of paradoxes dealing with contradictions in terms of speed vs thoroughness and short- vs long-term implications.

Research limitations/implications

The authors’ study provides several contributions. It advances understanding on the source and management of tensions experienced by government officials introducing e-government policies to support entrepreneurs during the Covid-19 pandemic. It also delineates multiple paradoxes experienced by government officials as new policies and systems were introduced. Finally, it offers a conceptual model explaining how government officials deal with multiple tensions emerging from the introduction of e-government policies in a developing country.

Originality/value

The prior literature has suggested that e-government initiatives would be guided by a prescriptive and tension-free process, driven by the interest to enhance governmental efficiency. This study reveals that developing e-government initiatives for entrepreneurs and existing businesses during the Covid-19 crisis was not immune to contradictions between government officials and the public. A conceptual model, based on multiple sources of tensions (government-related, business-related and external sources) and their management, is proposed. Implications and opportunities for further research are presented.

Details

Information Technology & People, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0959-3845

Keywords

Open Access
Article
Publication date: 13 September 2022

Lydia Amaro and Caren Brenda Scheepers

Women leaders struggle with the persistent paradoxical expectations. Literature suggests that a paradox mindset helps to leverage these tensions. This study aims to…

Abstract

Purpose

Women leaders struggle with the persistent paradoxical expectations. Literature suggests that a paradox mindset helps to leverage these tensions. This study aims to understand the nexus between the microfoundations of individual women leaders’ experiences, their responses and the organisational context, which enables or hinders their paradox mindset.

Design/methodology/approach

This study adopted a qualitative approach by conducting semistructured interviews with 14 women, all senior leaders in corporate South Africa.

Findings

The results reveal the interaction in the nexus between, firstly, women leaders’ authenticity and awareness as key anchors that enable them to adopt a paradox mindset and, secondly, the organisation’s role in creating hindrances or opportunities to leverage tensions. Women leaders in our sample applied one of two strategies: they either adapted to the environment or curated a subenvironment. This study shows that, if done authentically, through her own agency, a woman can influence interactions that make it easier to manage tensions within her environment, especially those created by negative performance evaluation because of unconscious institutional gender bias.

Research limitations/implications

The extent to which the findings of this research can be generalised is constrained by the selected research context.

Originality/value

This research contributes to the literature on paradox theory by revealing organisational contextual influencers, such as institutional bias in negative performance evaluation, which hinders a woman leader’s opportunity to be hired or promoted. These organisational influences also interact with women leaders’ ability to embrace paradox and internally leverage agentic and communal tensions.

Details

Gender in Management: An International Journal , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1754-2413

Keywords

Book part
Publication date: 17 September 2020

Joana Geraldi, Iben Stjerne and Josef Oehmen

Temporary and permanent organisations have contrasting yet co-dependent perspectives regarding time; temporary organisations are made to ‘die’, yet most of them exist to…

Abstract

Temporary and permanent organisations have contrasting yet co-dependent perspectives regarding time; temporary organisations are made to ‘die’, yet most of them exist to enable permanent organisations to ‘survive’. The authors studied the temporal tensions of strategic initiatives – that is, temporary organisations that aim to implement strategic change in permanent organisations. Our empirical data identified three temporal tensions emerging when senior managers timed their strategic initiatives: ambition versus realism when enacting the time horizon, patience versus urgency when enacting the pace, and clock time versus event time when enacting the temporal perspective. By evoking the literature on paradox and temporal work, the authors extend the view of temporality at the temporary and permanent interface and indicate how temporal work played an important role in creating, reinforcing, or transforming temporal tensions. The authors conclude by providing implications for theory and practice.

Details

Tensions and paradoxes in temporary organizing
Type: Book
ISBN: 978-1-83909-348-7

Keywords

1 – 10 of over 52000