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In this paper, silk powder around 1.5 micrometer average in size was developed and its dyeing property was compared with normal silk fiber. The results show that silk powder has a very high dye uptake property and can be dyed at room temperature; it can also be used to improve the dyeing property of some materials when it acts as a kind of additive agent. The K/S value of silk fiber is higher than that of silk powder. Their K/S value of silk fiber and silk superfine powder are influenced largely by the dye concentration. The WXRD diffraction curves showed that the crystallinity of silk powder is lower than that of silk fiber. FTIR spectra of silk powder showed that the intensity peak of CH₂-antisymmetrical stretching vibration largely decreased, and the peak of C=O symmetrical stretching vibration of amid bond moved to the high wave-number. TG patterns of samples showed that water (moisture) could be easily removed from the powder when the temperature was over 70°C, and the initial decomposition temperature of silk powder increased from 262.5°C to 277.5°C. Moreover, the silk powder showed higher residue than that of silk fiber at 600°C.

Colorfastness properties of dyed degummed and dyed stannic chloride weighted silk fiber were studied as a function of exposure to sunlight in air, washing with soap solution and spotting with alkalis.

Improved multi-voltine variety of degummed silk fibers was weighted with the treatment of stannic chloride at the varying pH level. Maximum weighting of silk fiber was achieved at the optimum SnCl₄ concentration, pH of the solution, time and temperature. The degummed (un-weighted) and weighted silk fibers were then dyed with Direct Blue 1 and Direct Red 28 dyes at the optimized dying conditions.

The role of base (Na₂CO₃) on dyeing of weighted silk fiber with Direct Red 28 was found very influential. The loss in tenacity of degummed silk fiber was higher than that of SnCl₄ weighted silk fiber when they were exposed to sunlight in air.

The colorfastness of weighted dyed silk was comparatively higher than that of un-weighted dyed silk.

Spun silk is one of the top grade textile materials, and its products have high added value and meet the needs of the market. However, the technology level and process design of silk spinning are still much lower than cotton spinning; especially singeing is applied on spun silk yarn, and generates waste materials. The purpose of this paper is to introduce a kind of pneumatic compact spinning, four-line compact spinning (FLCS), into silk spinning and study the corresponding spun yarn qualities.

First, taking the silk spinning frame FK501 as an example, the process of modification of FLCS is presented. Then, three kinds of spun silk yarns, 80 Nm (12.5tex), 100 Nm (10tex) and 120 Nm (8.3tex), are spun on the common silk spinning frame FK501 and the spinning frame modified with FLCS. The evenness, breaking strength and hairiness of spun yarns are tested and comparatively analyzed. After the ply yarn production, three singeing procedures should be applied on the ring ply yarns, while only two singeing procedures should be applied on the compact ply yarns, which is beneficial for material saving.

The results show that compared with ring spun silk yarns, the comprehensive quality of compact spun silk yarns is improved, especially the harmful long hairiness (=3 mm) of yarn. Compared with the single spun silk yarn, the comprehensive qualities of the ply yarn are improved; especially, the breaking strength of the ply yarns is two times larger than the single yarn. After singeing, the hairiness of the ply yarn is decreased greatly, and the evenness is also improved, while the strength is decreased. Compared with ring spun silk yarn, the singeing times of compact spun silk yarn can be decreased, and the gas consumption in each singeing is also decreased, which is beneficial for material saving.

In this paper, a kind of pneumatic compact spinning, FLCS, is introduced into the silk spinning. It is shown that compared with ring spun silk yarns, the comprehensive quality of compact spun silk yarns is improved, especially the harmful long hairiness (=3 mm) of yarn. After the ply yarn production, three singeing procedures should be applied on the ring ply yarns, while only two singeing procedures should be applied on the compact ply yarns, which is beneficial for material saving.

Weak repeatability is observed in handcrafted keypoints, leading to tracking failures in visual simultaneous localization and mapping (SLAM) systems under challenging scenarios such as illumination change, rapid rotation and large angle of view variation. In contrast, learning-based keypoints exhibit higher repetition but entail considerable computational costs. This paper proposes an innovative algorithm for keypoint extraction, aiming to strike an equilibrium between precision and efficiency. This paper aims to attain accurate, robust and versatile visual localization in scenes of formidable complexity.

SiLK-SLAM initially refines the cutting-edge learning-based extractor, SiLK, and introduces an innovative postprocessing algorithm for keypoint homogenization and operational efficiency. Furthermore, SiLK-SLAM devises a reliable relocalization strategy called PCPnP, leveraging progressive and consistent sampling, thereby bolstering its robustness.

Empirical evaluations conducted on TUM, KITTI and EuRoC data sets substantiate SiLK-SLAM’s superior localization accuracy compared to ORB-SLAM3 and other methods. Compared to ORB-SLAM3, SiLK-SLAM demonstrates an enhancement in localization accuracy even by 70.99%, 87.20% and 85.27% across the three data sets. The relocalization experiments demonstrate SiLK-SLAM’s capability in producing precise and repeatable keypoints, showcasing its robustness in challenging environments.

The SiLK-SLAM achieves exceedingly elevated localization accuracy and resilience in formidable scenarios, holding paramount importance in enhancing the autonomy of robots navigating intricate environments. Code is available at https://github.com/Pepper-FlavoredChewingGum/SiLK-SLAM.

This study aims to dye silk with natural pigments extract of Coreopsis tinctoria, by treating the fabrics with appropriate mordant under suitable dyeing conditions, to achieve good dyeing depth, fastness and ultraviolet (UV) protection.

Firstly, single factor experiments were used to determine the basic dyeing conditions of Coreopsis tinctoria. The optimal process conditions for direct dyeing were determined through orthogonal experiments. After that, the dyeing with mordant was used. Based on the previously determined optimal process conditions, silk fabrics were dyed with different mordanting methods, with different mordants and mordant dosages. The dyeing results were compared, in terms of the K/S values of the dyed fabrics, to determine the most appropriate dyeing conditions with mordant.

The extract of Coreopsis tinctoria can dye silk fabrics satisfactorily. Good dyeing depth and fastness can be obtained by using suitable dyeing methods and dyeing conditions, especially when using the natural mordant pomegranate rind and the rare earth mordant neodymium oxide. The silk fabrics dyed with Coreopsis tinctoria have good UV resistance, which allows a desirable finishing effect to be achieved while dyeing, using a safe and environmentally friendly method.

The composition of Coreopsis tinctoria is complex, and the specific composition of colouring the silk fibre has not been determined. There are many factors that affect the dyeing experiment, which have an impact on the experimental results.

The results of this study may help expand the application of Coreopsis tinctoria beyond medicine.

To the best of the authors’ knowledge, this paper is the first report on dyeing silk with the extract of Coreopsis tinctoria achieving good dyeing results. Its depth of staining and staining fastness were satisfactory. Optimum dyeing method and dyeing conditions have been identified. The fabric dyed with Coreopsis tinctoria has good UV protection effect, which is conducive to improving the application value of the dyeing fabric. The findings help offer a new direction for the application of medicinal plants in the eco-friendly dyeing of silk.

The textile industry has consumed large quantities of water and discharged large volumes of wastewater in the dyeing process. The study aims to characterize self-dyed silk with Rhodamine B (RhB) for fashion applications to reduce textile hazards to the environment and increase the added value of silk.

Bombyx mori was fed with RhB-colored mulberry leaves (1500 ppm). The effects of self-dyeing were investigated via color strength K/S, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope, X-ray diffraction, tensile strength, color fastness to washing, rubbing, perspiration and light.

Self-dyed silk possesses effective coloration and impressive color fastness (4–5/5), higher crystalline index (CrI) (73.26 ± 2.28%), less thermal stability and tenacity, slight change in amino acid composition compared with the pristine and no existence of harmful aromatic azo amines and arylamine salts.

The application of self-dyed silk with RhB dye has expanded new technology into fashion industry, contributing partly to economic growth and adding value to silk in the global supply chain. Besides, the self-dyeing will yield practical values in the reduction of dyeing discharge in textile industry.

Self-dyed silk was characterized for textile applications in comparison with pristine silk in terms of color strength and fastness as well as determined its polymeric properties relating to crystallinity, morphology, chemical composition, tensile properties and thermal stability which have not been investigated before.

Eri silk fiber has superior thermal insulation behavior, better softness than cotton fiber. However, Eri silk’s use in the commercial arena has not yet taken off. The purpose of the study is to explore the comfort properties of the fabric, which enhances the commercial acceptance of Eri silk clothing.

In this investigation, three different single knit Eri silk structures were produced with different loop lengths and yarn counts to analyze the influence of process variables on low-stress mechanical properties. To execute the research work, Eri silk spun yarn of three different linear densities (15 tex, 20 tex, 25 tex) were chosen. Three different knitted structures were produced, such as single jersey, popcorn and cellular blister, and two different loop lengths were also selected.

The cellular blister structure has shown appreciable low-stress properties next highest position was attained by the popcorn structure. Yarn fineness and loop length were significant with most of the low-stress properties.

The findings of this research will contribute to a greater awareness of Eri silk knitted fabric and its process parameters in relation to its commercial utility.

This study was conducted to explore the influence of knit structure, loop length and yarn count on the low-stress properties of Eri silk-based thermal clothing.

The purpose of this case is to expose readers to the dilemma of expanding domestically or internationally and simultaneously taking key decisions while expanding the business to the international markets. It could be a foundational case for understanding international expansion and growth strategies.

After the case analysis, students would be able to:

• understand the potential of the domestic market and the factors affecting the international expansion;

• evaluate the various methods to enter an international market;

• identify the challenges of expanding a business into emerging markets such as India;

• analyze the various growth and expansion strategies in an emerging market such as India; and

• assess the online promotion strategies in an emerging market.

NIVA, The Satin Collection, is a manufacturer and distributor of a luxury collection of silk and satin products. Founded in 2020, NIVA is based in Dubai with more than 1,000 customers. The products include silk bedding, silk sleepwear, fashion accessories and reusable satin masks, and they are made-to-order, custom-made and tailored locally in Dubai. Currently, all the operations are run and managed by the company’s founder, Purva. The only operation which is outsourced is the stitching process. The company is completely operating online and is currently promoting products only through social media platforms such as Instagram and Facebook.

Purva is planning to expand her business. The two options are extending her existing operations in the UAE and expanding to other emerging markets, starting with India. Purva needs to decide on a suitable internationalization strategy to decide whether it is the right decision to enter the Indian market, including an entry and promotion strategy in her target market. In addition, she needs to decide whether to continue with NIVA’s current business model in India. There might also be additional possible challenges for NIVA in entering the Indian market.

Postgraduate MBA students, other graduate-level management programs and undergraduate-level students.

Teaching notes are available for educators only.

CSS 5: International Business.

The purpose of this research paper is to examine the role of focal suppliers in strategic networks for internationalisation from the perspectives of small and medium‐sized Italian and Thai silk suppliers.

Multiple case studies of small and medium‐sized suppliers within the silk industries of Italy and Thailand were undertaken. In total, seventeen interviews and three observations were conducted with directors or managers of silk suppliers and a range of government agencies, associations and institutes involved with the silk industry, to identify significant current issues within the sector. Conceptually clustered and role ordered matrices were used as coding frameworks to reduce, structure and analyse the data.

Silk suppliers' networks may be co‐ordinated by a focal supplier that assumes the role of strategic leader. The involvement of a focal and strategically‐focused supplier may strengthen and integrate the resources and capabilities of silk suppliers in their networks and enable them to improve their international network development and positioning.

Further investigation is needed on the details of specific roles of focal suppliers in strategic networks.

Silk suppliers, their customers and government agencies involved with silk suppliers should: advocate and actively support the development of focal suppliers in their networks to enhance the effectiveness of their internationalisation process and strategy.

There tends to be a consensus in the literature about the influence of focal customers and larger organisations in strategic networks. This study highlights how small and medium‐sized silk suppliers adopt the roles attributed to focal firms and gain positioning advantages for themselves and other suppliers in their network.

In recent times, wool- and silk-blended fabrics are popular for creating glamourous products. Silk is blended to wool for creating more lustrous effect and to impart strength; on the other hand, wool is responsible for resilience, softness and warmth properties. Chemically both the fibres are protein-based, but the amount of amino acids is different. Due to this, the dye absorption behaviours of the two fibres from the same dye-bath are different. Wool is become darker than the silk fibre, if both the fibres are dyed together in a single bath dyeing process.

Here the wool fibres are first pre-treated with a commercial synthetic tanning agent (syntan) Mesitol HWS at three different pH values of 2.2, 3.2 and 4.2 and at three different concentrations: 5, 10 and 15 per cent. Then the syntan pre-treated wool fibres are dyed together with silk fibres maintaining the blend ratio as 80:20 by Telon Red MR, Telon Yellow M4GL and Telon Blue MRLW with sodium sulphate at three different concentrations of 10, 20 and 30 per cent.

The dye absorbency of the syntan-treated wool fibres decreased with increase in syntan concentration, whereas the colour strength of silk fibres increased. The resist effectiveness of wool fibres is increased from 6 to 59 per cent with increase of syntan concentration. So after the dyeing process, the colour strength of syntan-treated wool fibres are almost same with the colour strength of silk fibres. The washing fastness of the samples is improved, and wash fastness behaviour of both wool and silk fibres is almost same.

This paper gives an idea about the one bath dyeing process of wool- and silk-blended fabrics to achieve solid dyeing effect.