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1 – 10 of 187Hiroko Yokura and Sachiko Sukigara
For over a century, traditional Japanese cotton crepe fabrics have been popular for men’s underwear in the humid summer. Now, consumer demand is for crepe fabrics that are more…
Abstract
Purpose
For over a century, traditional Japanese cotton crepe fabrics have been popular for men’s underwear in the humid summer. Now, consumer demand is for crepe fabrics that are more attractive, reflecting a shift in use from underwear to women’s dresses. The purpose of this paper is to clarify how the structures of the crepe and its constituent yarns affect the physical properties, handle and silhouette formability of crepe fabrics for dresses.
Design/methodology/approach
Three plain-weave gray fabrics were finished by four different processes to change their crepe structures. The mechanical and surface properties of the fabrics were measured using the Kawabata evaluation system for fabrics. The primary hand values and silhouette formability of the fabrics were calculated using conversion equations based on the physical properties. The handle of the crepe fabrics and the aesthetic appearance of flared collars made of them were assessed by female students using the semantic differential method.
Findings
Comparing the fabrics made from the same gray fabric, the piqué crepe fabrics showed larger Hari (anti-drape) and Shari (crispness) than the others. The subjective hand value of softness was closely related to fabric thickness. The assessors preferred the fine piqué crepe fabrics over the wide piqué fabrics regarding both the tactile feeling of the fabrics and the aesthetic appearance of the flared collars. The attractiveness of the flared collars was dominated by the shear stiffness of the fabrics.
Originality/value
The fine piqué crepe fabric made from fine yarns produced a more preferable handle. The fine piqué fabric made from thicker yarns produced flared collars with silhouettes that are more attractive. This indicates that the fine piqué structure is a positive feature that makes the fabric suitable for various types of dresses.
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Chongjun Wu, Yutian Chen, Xinyi Wei, Junhao Xu and Dongliu Li
This paper is devoted to prepare micro-cone structure with variable cross-section size by Stereo Lithography Appearance (SLA)-based 3D additive manufacturing technology. It is…
Abstract
Purpose
This paper is devoted to prepare micro-cone structure with variable cross-section size by Stereo Lithography Appearance (SLA)-based 3D additive manufacturing technology. It is mainly focused on analyzing the forming mechanism of equipment and factors affecting the forming quality and accuracy, investigating the influence of forming process parameters on the printing quality and optimization of the printing quality. This study is expected to provide a µ-SLA surface preparation technology and process parameters selection with low cost, high precision and short preparation period for microstructure forming.
Design/methodology/approach
The µ-SLA process is optimized based on the variable cross-section micro-cone structure printing. Multi-index analysis method was used to analyze the influence of process parameters. The process parameter influencing order is determined and validated with flawless micro array structure.
Findings
After the optimization analysis of the top diameter size, the bottom diameter size and the overall height, the influence order of the printing process parameters on the quality of the micro-cone forming is: exposure time (B), print layer thickness (A) and number of vibrations (C). The optimal scheme is A1B3C1, that is, the layer thickness of 5 µm, the exposure time of 3000 ms and the vibration of 64x. At this time, the cone structure with the bottom diameter of 50 µm and the cone angle of 5° could obtain a better surface structure.
Originality/value
This study is expected to provide a µ-SLA surface preparation technology and process parameters selection with low cost, high precision and short preparation period for microstructure forming.
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Wei Zhang, Jiali Weng, Shang Hao, Yuan Xie and Yonggui Li
Fabrics with photothermal conversion functions were developed based on the introduction of shape stable composite phase change materials (CPCMs).
Abstract
Purpose
Fabrics with photothermal conversion functions were developed based on the introduction of shape stable composite phase change materials (CPCMs).
Design/methodology/approach
Acidified single-walled carbon nanotubes (SWCNTs) were selected as support material to prepare CPCMs with n-octadecane to improve the thermal conductivity and shape stability. The CPCMs were finished onto the surface of cotton fabric through the coating and screen-printing method. The chemical properties of CPCMs were characterized by Fourier transform infrared spectrometer, XRD and differential scanning calorimetry (DSC). The shape stability and thermal conductivity were also evaluated. In addition, the photothermal conversion and temperature-regulating performance of the finished fabrics were analyzed.
Findings
When the addition amount of acidified SWCNTs are 14% to the mass of n-octadecane, the best shape stability of CPCMs is obtained. DSC analysis shows that the latent heat energy storage of CPCMs is as high as 183.1 J/g. The thermal conductivity is increased by 84.4% compared with that of n-octadecane. The temperature-regulating fabrics coated with CPCMs have good photothermal conversion properties.
Research limitations/implications
CPCMs with high latent heat properties are applied to the fabric surface through screen printing technology, which not only gives the fabric the photothermal conversion performance but also reflects the design of personalized patterns.
Practical implications
CPCMs and polydimethylsiloxane (PDMS) are mixed to make printing paste and printed cotton fabric with temperature-regulating functional is developed.
Originality/value
SWCNTs and n-octadecane are composited to prepare CPCMs with excellent thermal properties, which can be mixed with PDMS to make printing paste without adding other pastes. The fabric is screen-printed to obtain a personalized pattern and can be given a thermoregulatory function.
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This paper aims to investigate the feasibility of adding macro-textures to triangle meshes for additive manufacturing (AM) focusing on possible time and quality issues in both…
Abstract
Purpose
This paper aims to investigate the feasibility of adding macro-textures to triangle meshes for additive manufacturing (AM) focusing on possible time and quality issues in both software processing and part fabrication.
Design/methodology/approach
A demonstrative software tool was developed to apply user-selected textures to existing meshes. The computational procedure is a three-dimensional extension of the solid texturing method used in computer graphics. The tool was tested for speed and quality of results, considering also the pre- and post-processing operations required. Some textured meshes were printed by different processes to test build speed and quality.
Findings
The tool can handle models with realistic complexity in acceptable computation times. Parts are built without difficulties or extra-costs achieving a good aesthetic yield of the texture.
Research limitations/implications
The tool cannot reproduce sample patterns but requires the development of a generation algorithm for different type of textures. Mesh processing operations may take a long time when very fine textures are added to large parts.
Practical implications
Direct texturing can help obtain parts with aesthetic or functional textures without the need for surface post-treatments, which can be especially difficult and expensive for plastic parts.
Originality/value
The proposed method improves the uniformity and consistency of textures compared to existing approaches, and can support future systematic studies on the detail resolution of AM processes.
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Guillermo Guerrero-Vacas, Jaime Gómez-Castillo and Oscar Rodríguez-Alabanda
Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using…
Abstract
Purpose
Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.
Design/methodology/approach
PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.
Findings
PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.
Originality/value
The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.
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Giovanni Gómez-Gras, Marco A. Pérez, Jorge Fábregas-Moreno and Guillermo Reyes-Pozo
This paper aims to investigate the quality of printed surfaces and manufacturing tolerances by comparing the cylindrical cavities machined in parts obtained by fused deposition…
Abstract
Purpose
This paper aims to investigate the quality of printed surfaces and manufacturing tolerances by comparing the cylindrical cavities machined in parts obtained by fused deposition modeling (FDM) with the holes manufactured during the printing process itself. The comparison focuses on the results of roughness and tolerances, intending to obtain practical references when making assemblies.
Design/methodology/approach
The experimental approach focuses on the comparison of the results of roughness and tolerances of two manufacturing strategies: geometric volumes with a through-hole and the through-hole machined in volumes that were initially printed without the hole. Throughout the study, both alternates are explained to make appropriate recommendations.
Findings
The study shows the best combinations of technological parameters, both machining and three-dimensional printing, which have been decisive for obtaining successful results. These conclusive results allow enunciating recommendations for use in the industrial environment.
Originality/value
This paper fulfills an identified need to study the dimensional accuracy of the geometries obtained by additive manufacturing, as no experimental evidence has been found of studies that directly address the problem of the FDM-printed part with geometric and dimensional tolerances and desirable surface quality for assembly.
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Abstract
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The field of broad-based employee ownership within corporations is a specific application of the foundational topic of property ownership. It is situated at the intersection of a…
Abstract
Purpose
The field of broad-based employee ownership within corporations is a specific application of the foundational topic of property ownership. It is situated at the intersection of a broad range of scholarly disciplines including economics, law, finance and management. Each discipline contributes vocabulary and distinctions describing this field. That broad spectrum of disciplinary inquiry is a strength but it also lends a “ships passing in the night” quality to discussions of employee ownership. This paper attempts to unravel the narrative diversity surrounding this topic. Four meanings of ownership are introduced. Those meanings are in turn embedded within two abstract models of the corporation; the corporation as property and the corporation as social institution.
Design/methodology/approach
There is no experimental design The paper presents a conceptual overview and introduces a taxonomy of four meanings and two models of ownership.
Findings
Four meanings of ownership are introduced. The meanings are ownership as compensation, investment, retirement and membership. Those meanings are in turn embedded within two abstract models of the corporation; the corporation as property and the corporation as social institution.
Research limitations/implications
No hypotheses are advanced. This is not a research paper. A conceptual overview that makes use of taxonomy of meanings and models is introduced to help clarify confusions abundant in the field of employee ownership. Readers may differ with the categories of meanings and models introduced in this conceptual overview.
Practical implications
The ambition of the paper is to describe the various meanings and models of employee ownership presently in use in both academic and applied settings. It is not necessary or desirable to assert the primacy of a single meaning or model in order to achieve progress. The analysis provided here surfaces a range of assumptions about ownership that have heretofore been implicit in both scholarship and in practice. Making those assumptions explicit should prove useful to both scholars and practitioners of employee ownership.
Social implications
The concept of employee ownership enjoys a relatively broad appeal with the public. Among the academic disciplines that have trained their lights upon it, a more mixed reception prevails. Much of the academic and policy controversy derives from confusion about the nature and structure of employee ownership. This paper attempts to address that confusion by presenting a taxonomy of meanings and models that may prove useful for future research.
Originality/value
This study is one of the first efforts to comprehinsively map the various meanings and models of broad-based employee ownership.
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Manuel Jesus, Ana Sofia Guimarães, Bárbara Rangel and Jorge Lino Alves
The paper seeks to bridge the already familiar benefits of 3D printing (3DP) to the rehabilitation of cultural heritage, still based on the use of complex and expensive…
Abstract
Purpose
The paper seeks to bridge the already familiar benefits of 3D printing (3DP) to the rehabilitation of cultural heritage, still based on the use of complex and expensive handcrafted techniques and scarce materials.
Design/methodology/approach
A compilation of different information on frequent anomalies in cultural heritage buildings and commonly used materials is conducted; subsequently, some innovative techniques used in the construction sector (3DP and 3D scanning) are addressed, as well as some case studies related to the rehabilitation of cultural heritage building elements, leading to a reflection on the opportunities and challenges of this application within these types of buildings.
Findings
The compilation of information summarised in the paper provided a clear reflection on the great potential of 3DP for cultural heritage rehabilitation, requiring the development of new mixtures (lime mortars, for example) compatible with the existing surface and, eventually, incorporating some residues that may improve interesting properties; the design of different extruders, compatible with the new mixtures developed and the articulation of 3D printers with the available mapping tools (photogrammetry and laser scanning) to reproduce the component as accurately as possible.
Originality/value
This paper sets the path for a new application of 3DP in construction, namely in the field of cultural heritage rehabilitation, by identifying some key opportunities, challenges and for designing the process flow associated with the different technologies involved.
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