1,029 research outputs found
First-Principles Calculation of Electric Field Gradients and Hyperfine Couplings in YBa2Cu3O7
The local electronic structure of YBa2Cu3O7 has been calculated using
first-principles cluster methods. Several clusters embedded in an appropriate
background potential have been investigated. The electric field gradients at
the copper and oxygen sites are determined and compared to previous theoretical
calculations and experiments. Spin polarized calculations with different spin
multiplicities have enabled a detailed study of the spin density distribution
to be made and a simultaneous determination of magnetic hyperfine coupling
parameters. The contributions from on-site and transferred hyperfine fields
have been disentangled with the conclusion that the transferred spin densities
essentially are due to nearest neighbour copper ions only with marginal
influence of ions further away. This implies that the variant temperature
dependencies of the planar copper and oxygen NMR spin-lattice relaxation rates
are only compatible with commensurate antiferromagnetic correlations. The
theoretical hyperfine parameters are compared with those derived from
experimental data.Comment: 14 pages, 12 figures, accepted to appear in EPJ
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From rag trade to retail: garment failure and the potential for sustainable fashion
Around 1.8 million tonnes of clothing waste is generated annually in the UK, accounting for around 5% of total UK household waste, with the lifetime of many garments unduly short. As a result of greater attention being placed on waste reduction at European Union and national government level, however, interest in the potential for increased garment lifetimes has grown in recent years and, despite obvious tensions between fashion and longevity, retailers have begun to engage in the debate.
This paper presents findings from a research project undertaken for WRAP (Waste and Resources Action Programme) aimed at an industry-supported approach to measuring, specifying and communicating aspects of clothing longevity. Although a high proportion of garments are thrown away in wearable condition, many of which are reused, others are discarded because they are damaged or worn out. This study was concerned with the latter. Although a literature review identified recent studies addressing the context surrounding the fashion industry and elements of the ‘fast fashion’ debate, providing some explanation for the disposable nature of much fashion, no primary research relating to garment failure was found. A visual survey of discarded clothing was thus undertaken in order to increase knowledge and understanding of reasons for garment failure. Visits were made to three UK based textile reuse and recycling organisations. Around 1,500 discarded garments in a failed condition were subject to a systematic analysis, categorised by type of garment and condition and with visual images recorded. Only garments no longer ‘fit for purpose’, deemed not to be in a good enough condition to be re-sold in the UK, were assessed. The method of first hand observation enabled consideration of why items had been discarded and had the benefit of being less subjective and not dependent upon the memory of people who had disposed of them.
The main reasons why garments appeared to have been discarded were identified as colour fading and problems relating to fabric quality such as pilling of knitted items and fabric breakdown in the form of fraying and thinning. Other key issues were general wear around the crotch of trousers and jeans, discolouration in white shirts and holes in seams. The detailed findings, presented by type of garment and type of fabric, will be useful to fashion retailers and brands wishing to respond to growing concerns about waste arising from short-lived clothing. It should enable them to review their performance criteria and testing procedures in order to adjust garment specifications, and to market garments appropriately
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Interdisciplinary educational approaches to clothing longevity
How do we encourage and enable interdisciplinary systems thinking approaches to sustainable fashion design and business education? In preparation for a workshop at the 2017 PLATE conference, this paper introduces the context of a toolkit – The Clothing Durability Dozen (Cooper at al, 2016b) – aimed at enabling students to collaborate and learn about clothing longevity across disciplines and creating a better understanding of the roles that different departments can play in placing sustainable design strategies at the heart of the clothing industry. In line with education for sustainable development (ESD) principles, objectives include stimulating learning and promote core competencies, such as critical and systemic thinking, collaborative decision-making, and taking responsibility for present and future generations. In the workshop, participants will trial and contribute to the development of the toolkit and any necessary supporting material, the final version of which will be available for use as an educational tool
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Product development and supply: help or hindrance to clothing longevity?
Designing longer lasting clothing helps to reduce unsustainable levels of product disposal and subsequent waste. This has led to a call for retailers to enhance clothing longevity, supported by new business models to reduce any impact on competitiveness. While some research suggests that a significant proportion of consumers would buy longer lasting clothes, this view is not necessarily accepted by industry strategists. This paper, which reports on research undertaken for WRAP (Waste and Resources Action Programme), explores conflicting priorities between commercial and sustainable practice, and problematic trade-offs in the supply chain between commercial, technical and design aspects of reducing the environmental impact of clothing. The study adopted a mixed methodology, incorporating qualitative interviews and a survey, and encompasses views of retailers, manufacturers and suppliers from different segments of the UK fashion market.
The findings confirm that retailers and brands drive the new product development process and set standards for their supply chains, but globalization, product churn and testing regimes challenge the critical path schedule. Although current tests confirm product quality (WRAP, 2013), there is a perception within industry that designing for longevity increases testing, inflating the risk of failure and extending lead-times, resulting in a mismatch between cost, time and longevity priorities that limits adoption of design for longevity. Meanwhile, clothing longevity is not perceived to add value for many consumers and therefore is not prioritised. While it is technically possible to enhance clothing longevity, the findings demonstrate empirically that this deviates from current commercial drivers of global clothing supply chains. By combining different perspectives on supply chains, new product development and sustainability, inherent conflicts are revealed
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Opportunities and challenges of new product development and testing for longevity in clothing
Many types of clothing are now seen as disposable by consumers in the UK even though durability is among the top criteria that consumers claim to use when buying garments (WRAP, 2012). Routine tests for clothing performance carried out by retailers are generally designed to ensure garments are 'fit for purpose', not to establish durability or longevity. Designing clothing that lasts longer is, however, key to reducing waste and has become a government policy objective (Defra, 2011).
This paper discusses the findings from a recent research project, carried out for WRAP (Waste and Resources Action Programme), that investigated the opportunities for measuring, specifying and communicating aspects of clothing longevity within a Longevity Protocol. The Protocol is intended to enable retailers to obtain a reliable indication of garment life expectancy and was piloted in conjunction with clothing industry practitioners. It incorporates recommendations for best practice in product development and a testing regime that provides an indication of garment life expectancy (WRAP, 2014).
Overall, the findings from the pilot suggest that it is possible to test for garment longevity, however, this
process can be drawn-out and may not fit easily into the normal product development process. Furthermore, variations in consumer wearing patterns and laundering make it difficult for retailers to guarantee and communicate product lifetimes in absolute terms.
The research adds to a growing body of evidence that supports the concept of design for clothing longevity. The findings will help to inform strategies for the implementation of government policy on sustainable clothing, but point to the need for refined testing processes to support this agenda
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Pilling in knitwear – a clothing longevity problem beyond design
The environmental impact of clothing could be reduced by extending garment lifetimes, and many clothing retailers are now exploring design for longevity as a sustainable approach. In order for products to meet durable design standards consistently, global supply chain processes must be managed and controlled to avoid quality problems and early product failure. This paper uses a single case study to explore the challenges of meeting specified durable product standards in production by tracing and observing the identification and resolution of a quality issue affecting the durability of luxury knitwear. The research demonstrates that new tests and processes could enable durable products to be produced more consistently, but also identifies the obstacles and limitations to implementing these enhanced procedures. The paper proposes that effective production management of durable clothing may be more difficult within global supply chains where differences in business culture, operational practice and knowledge exist between companies. Supply chain models that emphasise shared values, knowledge and information exchange, trust and collaboration are considered as the most effective in delivering sustainable products. It concludes by identifying a range of conflicting priorities between commercial and sustainable practice that must be addressed to achieve consistency in durable clothing production, and makes recommendations for industry and future research
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New product development and testing strategies for clothing longevity
Many garments have short life-spans, contributing to excessive carbon emissions, water consumption and waste. This paper reports on a research project which aimed to identify expectations of clothing longevity, examine the NPD process within the supply chain and identify opportunities for change, evaluate the potential for innovative technologies and improved product testing, and explore business practices aimed at more sustainable approaches to NPD. The paper provides an overview of the two-year project, presenting key findings from data collection that included interviews with 31 industry practitioners, three consumer focus groups, three industry and consumer round tables, an expert workshop, and four pilot actions undertaken with UK clothing retailers to evaluate key issues. The research identified and explored themes relating to NPD that could enable increased garment lifetimes, which were consolidated into six areas: the adoption of advanced textile processes and finishing techniques, action to overcome constraints on appropriate product testing, the potential for retailers to influence consumer behaviour, a loss of technical expertise and lack of multi-disciplinary collaboration, failure to embed good practice early in the NPD process, and evidence to encourage retailers and brands to adopt new business models. Industry and government policy recommendations were proposed to improve knowledge-sharing, strengthen the business case and influence consumer behaviour, while further research may be needed on the adoption of new garment and textile technologies, the business case and the global context of the clothing industry
Trick or treat?
The purpose of this article is to draw attention to current transgressions in scientific writing and to promote commitment to ethical standards and good science. All participants of any research project, particularly under interdiciplinary team approach, should not only play an active role on the management and carrying out of their study but also ensure that their study is not fraudulent. Manuscript fabrication, data and/or figure manupilation, piracy (plagiarism), sloppy research, and transgressions in authorship are reasons for loss of scientific value and records, retraction of articles, and application of a variety of sanctions
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