Zoran Stjepanovič

Computer‐aided processes in garment production: features of CAD/CAM hardware

Follows a presentation at a symposium in 1993 where the authors presented an experimental investigation on a fluttering membrane for use in a wind‐tunnel. Analyses the fluttering of an object by a theoretical method. Compares the experimental results with those of the theoretical and discusses their effectiveness. States that the present analysis is effective for approximate investigations.

Development and evaluation of an e-learning course for deaf and hard of hearing based on the advanced Adapted Pedagogical Index method

Web-based and adapted e-learning materials provide alternative methods of learning to those used in a traditional classroom. Within the study described in this article, deaf and hard of hearing people used an adaptive e-learning environment to improve their computer literacy. This environment included streaming video with sign language interpreter video and subtitles. The courses were based on the learning management system Moodle, which also includes sign language streaming videos and subtitles. A different approach is required when adapting e-learning courses for the deaf and hard of hearing: new guidelines must be developed concerning the loading and display of video material. This is shown in the example of the e-learning course, ECDL (European Computer Driving Licence). The usability of the e-learning course is analyzed and confirmed using two methods: first, the Software Usability Measurement Inventory (SUMI) evaluation method, and second, the Adapted Pedagogical Index (AdaPI), which was developed as part of this study, and gives an index to measure the pedagogical effectiveness of e-learning courses adapted for people with disabilities. With 116 participants, of whom 22 are deaf or hard of hearing, the e-learning course for the target group has been found suitable and appropriate according to both evaluation methods.

Accessible and adaptive e-learning materials: considerations for design and development

The aspect of accessibility and adaptivity is important for future of e-Learning applications. Creating e-Learning applications for everybody, including people with special needs, remains the question. The problem with development of e-Learning applications for everybody is that learner ability and weaknesses are usually neglected as important factors while developing applications. Most of nowadays applications offer lots of unclear information, unsuitable contents and non-adapted mechanisms. This paper suggests basic guidelines for successful design and structuring accessible and adaptive e-Learning applications that consider the requests and needs of people with special needs. It provides an example of design and realization of e-Learning application for receiving ECDL certificate, which includes easy adaptivity and basic accessibility factors. Experimental results of usability testing and pedagogical effectiveness have shown that material, designed following these guidelines, is appropriate and that there must be extra attention paid to learnability factor in the future.

How can HCI factors improve accessibility of m-learning for persons with special needs?

Mobile learning, or m-learning, respectively, can be stated as an upgrade of e-learning, valuable for mobile users using new mobile technology and telecommunication systems. The article presents the influence of mlearning system intended for supporting a remote engineering application. Here, we examined the usability of the application designed for people with special needs taking into account the main human-computer interaction factors. User interface for mobile systems served as a platform for examining the functionalities of a micro-controlled system. Two usability testing methods, involving some persons with special needs, were conducted in order to examine the usability of the system. The results gained are valuable for designing improved, future-oriented mlearning applications.

Study regarding the virtual prototyping of garments for paraplegics

The sitting position is very common in everyday life and therefore any garment should be comfortable in that positon. It is especially important for those who are disabled and are confined to a sitting position throughout life. These include paraplegics whose restricted movements are due to paralysis of the lower limbs and restrict them to a wheelchair. Garments for a sitting position should meet certain particular needs like the body dimensions and postures of each individual. Design considerations should provide ergonomic comfort in a sitting position and include functional requirements due to limitations of strength and mobility in such a way that they do not cause additional health problems to paraplegics, e.g. skin irritations, pressure sores, obstruction of the blood flow etc., but rather to improve the quality of life for paraplegics. Today, the development of garments is practically impossible to imagine without the assistance of 3D CAD systems for the virtual prototyping of garments, which usually provide only the 3D body models in a standing position. The aim of this study was to explore the possibilities for the virtual prototyping of garments in regard to the sitting position, using the OptiTex 3D commercial CAD system. For this purpose 3D scans of subjects in sitting position were performed using a general-purpose ATOS II 3D optical scanning system. In addition, processing techniques of the human body mesh modeling and surface reconstruction techniques were involved to obtain a sitting 3D body model. The garments’ basic pattern designs for a standing position were constructed according to the rules of the M. Müller&Sohn construction system. Their reconstruction into garments’ basic pattern designs for a sitting position were performed by using the virtual measured dimensions of the scanned 3D body model in a sitting position, and virtual prototyping of the garments. Comparisons between the dimensions of the real and the 3D body models were carried out, as well as a comparison between the real sewn and virtually developed garments. The research showed that a reliable sitting 3D body model was achieved by used scanning technology, modeling and reconstruction techniques, as well as the usefulness and effectiveness of the virtual prototyping of the garments for a sitting position. In this study fully mobile individuals were involved to avoid unnecessary burdening of paraplegics in this stage of the research. The experiences gained from this study will enable us to include paraplegics within the study during the scanning and anthropometric survey with the aim of designing a general parametric 3D body model. Its body dimensions and postures would be possible for adapting from able-bodied persons with the purpose of developing individual garments for paraplegics.

Selection of suitable sewing needle using machine learning techniques

Selection of suitable sewing needle is one of the most important parameters for ensuring an effective and fault‐free sewing process. This task requires good knowledge of basic characteristics of a sewing needle, i.e. needle type, point shape and needle fineness. Also good knowledge of sewing materials is required. The contribution presents an analysis of important parameters that influence the sewing needle selection in women’s underwear production. The importance of those parameters in ensuring the appropriate seam quality is described. The selection of a suitable sewing needle was carried out on the basis of analysis of influential sewing parameters with application of machine learning from examples.

Influence of a Spinning Process on Spun Yarn Quality and Economy of Yarn Production

Presents the mechanical models of ring, rotor and air‐jet staple yarn formation. The analysis of formation peculiarities has enabled the establishment of differences among them in micro‐ and macrostructure as well as in their mechanical and physical properties. The comparison of yarn and fabric quality parameters will be very valuable for weavers, knitters, garment manufacturers, finishers and designers. Gives productivity, spinability and economic factors for ring spinning, OE‐rotor and air‐jet spinning processes.

The prediction of cotton yarn properties using artificial intelligence

Abstract The possibility of determining cotton yarn properties using artificial intelligence techniques is studied. The advantages of this approach are presented. On the basis of experimental results the usage of machine learning and expert systems in the domain of spinning textile technology is estimated and suggestions for further research work are given.

Seam properties of ultrasonic welded multilayered textile materials

This study examined the effects of ultrasonic welding parameters on bond strength, seam thickness and seam stiffness, as well as water permeability. For study purpose, two types of four-layered fabrics with same compositions and different areal densities suitable for inner part of sport shoes were used. Two different types of seams, lapped and superimposed, were applied for ultrasonic welding and also compared by traditional seam applied by shoe manufacturer. The morphology of different type of seams was also analyzed to observe the influence of welding parameters on the layers during the ultrasonic welding process. Bonding strength was found to depend on the seam type and composition of the joined fabric layers. It was confirmed by the shoe manufacturer that all the produced welded seams provided the requested minimum bond strength to be suitable for the use of the shoes. The traditional seams applied by the shoe manufacturer were thicker but had lower stiffness in comparison to all welded seams. It was also found out that ultrasonic welding damaged the membrane, which was confirmed by no water resistance of welded seams. Statistical analysis showed that ultrasonic welding parameters, such as welding frequency and velocity, influence the bond strength, thickness, and bending stiffness of welded seams, but the obtained results were statistically insignificant.

Applying Heat for Joining Textile Materials

The middle of the last century presents the beginning of a wide use of heat technologies for joining of the textile materials. Up to now, adhesive bonding/fusing of textile materials by application of heat and pressure during the determinate time has become a wide‐use technology for manufacturing numerous kinds of textile products, such as outdoor and sport garments, underwear, swimming suits, medical gowns, toys, and automotive seating fabrics. Fusing and welding technologies of textiles represent today a signifi‐ cant competition to traditional sewing, because the technological process is quick and energy efficient. The welding and fusing of textiles represent a great opportunity for providing a good performance as well as aesthetic appearance. New types of fusing/ welding machines with high technological solutions regarding the functions, low energy consumptions, and environmental‐friendly effects are placed on the market. This chapter presents fusing, hot air and hot wedge welding techniques, suitable for joining of textile materials. The theoretical background and fundamental working principles of the equipment for each technology are presented in the first part of the chapter. Special attention is given to presentation of thermoplastic adhesives, textile substrates for fusible interlinings, and welding tapes. Next, the fusing/welding methods and their parame‐ ters are described, and the methods for quality evaluation of fused/welded panels are presented. The effect of fusing/welding parameters, selected methods depending on applied fabrics, fusible interlinings and welding tapes, and used fusing/welding machines are discussed separately. Factors effecting the quality of fused and hot air/ wedge welded panels are supported with latest scientific findings. The advantages and disadvantages of the presented techniques are discussed together with the applications areas of each of the presented techniques. The new application opportunities are also highlighted at the end of the chapter.