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Uses Newmark’s method to carry out a time‐stepping finite element analysis to predict the behaviour of a cloth garment as it falls from an initial horizontal position to a final position draped around a human body form. Bases the finite element model on a simple beam element, in order to minimize the computational time. Accounts for large displacement behaviour by including the element geometric stiffness. Bases the body form on anthropomorphic data produced by a shadow scanner. Enlists a novel scheme to model the contact between the cloth and the underlying body form. Uses the finite element model to provide data for an animated display and finds that it produces sufficiently realistic results for the garment designer’s purposes.

This paper describes a method for the construction of rational polynomial paths that does not require the apriori specification of either vertices or weights. An algebra of rational paths is developed within which paths with positive weights can be generated from more elementary paths with the same property. Case studies demonstrate that the path algebra can provide a simple means of obtaining exact rational representations of paths defined in non‐rational terms.

The problem of constructing the convex hull of a set of points and of curvilinear segments arises in many applications of geometric analysis. Although there has been much work on algorithms for the convex hull of a finite point set, there has been less on methods for dealing with circular line segments and the implementation issues. This paper describes a new method for finding the convex hull of a planar set of straight and circular line segments. It then concentrates on the implementation of the algorithm.

Virtual maintenance simulation is of great importance to help designers find and avoid design problems. During its simulation phase, besides the high precision requirement, collision detection must be suitable for all irregular objects in a virtual maintenance environment. Therefore, in this paper, a collision detection approach is proposed based on encapsulation for irregular objects in the virtual maintenance environment.

First, virtual maintenance simulation characteristics and several commonly used bounding boxes methods are analyzed, which motivates the application of encapsulation theory. Based on these, three different encapsulation methods are oriented to the needs of simulation, including encapsulation of rigid maintenance objects, flexible maintenance objects and maintenance personnel. In addition, to detecting collisions accurately, this paper divides the detection process into two stages. That is, in the first stage, a rough detection is carried out and then a tiny slice space is constructed to generate corresponding capsule groups, which will be redetected in the secondary stage. At last, several case studies are applied to illustrate the performance of the methodology.

The automatic construction algorithm for bounding boxes can be adapted to all forms of objects. The number of detection primitives are greatly reduced. It introduces the reachable space of the human body in maintainability as the collision search area.

The advantages of virtual maintenance simulation could also be advantageous in the industry with further studies. The paper believes this study is of particular interest to the readers of your journal.

The purpose of this paper is to conduct a survey on research in fabric and cloth simulation using mass spring model. Also in this paper some of the common methods in process of fabric simulation in mass spring model are discussed and compared.

This paper reviews and compares presented mesh types in mass spring model, forces applied on model, super elastic effect and ways to settle the super elasticity problem, numerical integration methods for solving equations, collision detection and its response. Some of common methods in fabric simulation are compared to each other. And by using examples of fabric simulation, advantages and limitations of each technique are mentioned.

Mass spring method is a fast and flexible technique with high ability to simulate fabric behavior in real time with different environmental conditions. Mass spring model has more accuracy than geometrical models and also it is faster than other physical modeling.

In the edge of digital, fabric simulation technology has been considered into many fields. 3D fabric simulation is complex and its implementation requires knowledge in different fields such as textile engineering, computer engineering and mechanical engineering. Several methods have been presented for fabric simulation such as physical and geometrical models. Mass spring model, the typical physically based method, is one of the methods for fabric simulation which widely considered by researchers.

Some areas of the apparel industry, such as folding and sewing, are still labor intensive. The purpose of this paper is to present a new fuzzy visual servoing strategy for the folding of fabric strips by robotic manipulators.

Three stages of the folding task are distinguished experimentally, the initial laying, the true folding, and the final laying. An indirect visual servoing fuzzy system, employing two cameras, is developed to guide the robot along each of the stages.

The proposed scheme manages to successfully fold some of the tested materials. The experimental results are promising and well within the limitations posed by both the employed equipment and the nature of the handled materials.

This study is limited to rectangular strips of fabrics and does not consider the speed of the process.

The resulting system provides a stepping stone for the introduction of automation to currently labor‐intensive areas of the apparel industry.

The separate folding stages reduce the complexity of the overall system and the introduced visually extracted features allow a closer monitoring of the process.

The size prediction of garment is an important part in the process of the garment design and production, and it is also one of the most important features in warp-knitted computer-aided design system. The purpose of this paper is to realize the auto-generation of the garment templates using JavaScript and WebGL technologies, based on the prediction of the size of warp-knitted seamless sportswear.

The warp-knitted jacquard technology is used to produce the warp-knitted seamless sportswear, which is divided into suits and tights. In order to achieve the purpose of this study, the dimensions of four kinds of jacquard patterns knitted under different knitting conditions are measured and the crosswise and longitudinal size shrinkage percentages are also calculated. Then, the relationship between the yarn count and the drawing density as well as the size shrinkage percentage is studied and a size prediction model for warp-knitted jacquard fabric is established. Next, according to the results of the size calculation, the point positions of the garment boundary in the mathematical coordinate system is determined. The color formula is built by the two-dimensional mathematical matrix. Finally, combined with the coordinate position and color information, the template can be drawn automatically.

Based on the size prediction model of warp-knitted garment, the template generation of warp-knitted full-form sportswear on WebGL-enabled web browser is realized, which is proven to be an effective computer-aided design method for warp-knitted garments.

Because of limited researches, only two groups of yarns and four kinds of jacquard patterns were studied. A vaster database should be built and smooth curve, accurate coordinate needs to be optimized in the further research.

The size prediction model for warp-knitted jacquard garment and garment template auto-generation of warp-knitted computer-aided design system will simplify the fabric technical design process, shorten design time and improve the efficiency of new product development.

The size prediction model for warp-knitted jacquard garment and garment template auto-generation of warp-knitted computer-aided design system will provide the industries a guidance for new sample development and it also can shorten the development time and lower cost.

This author analyzes the relationship between the size characteristics and knitting technology of warp-knitted jacquard patterns, proposes a model of size prediction and realizes the auto-drawing of the garment template in the warp-knitted CAD system, which provides a reference for the new product design and development of warp-knitted seamless sportswear.

Undesirable effect of asymmetric drape often occurs when cutting patterns of flared skirt on cross. Out of this reason garment seams twist toward the front or back or folds form different shapes on each side of the garment and this lowers garment aesthetic appearance. The new measuring procedure for asymmetric skirt drape near the side seam, based on bottom traces geometry, was developed in this paper. The experiment with four‐gored skirts of six lightweight fabrics was made. It was found that asymmetric drape depends on combination of grain lines directions of front and back panels of a skirt. There were made general conclusions relating skirt asymmetric drape with various fabric characteristics, such as bending rigidity, extensibility, shear rigidity, fabric weight and drape coefficient in this article. According to developed measuring procedure a final objective evaluation of skirt asymmetric drape rate will be done further.

The purpose of this paper is to focus on the development of a thorough method for the macromechanical analysis of fabrics.

The homogenization method was implemented for the generation of continuum equivalent model for the plain woven structure. Keystone of the method is the mesomechanical analysis of the textile unit cell for the evaluation of the apparent properties and the generation of an equivalent macromechanical model supporting the mechanical performance of the structure. The finite element method (FEM) using beam elements was applied for the mechanical analysis of the discrete model of the unit cell and the FEM using shell elements was applied for the analysis of the continuum macromechanical model.

The tensile, shear and bending test of the unit cell were simulated. The constitutive equations of the continuum model were formed considering equivalent performance with the discrete model.

The reliability of the equivalent model in tensile, shear (in‐plane) and bending (out‐of‐plane) deformation was achieved even for asymmetric woven structures. The low computational power demanded for the meso‐ and macro‐mechanical modelling and analysis is a beneficial feature of the proposed method.

The purpose of this study is to explain how and why firms configure copyright practices when confronted with state-sanctioned laws and informal customs projected by local ethnic or religious communities.

A multi-case inductive study of four film-producing organizations within the Nigerian film industry (i.e. Nollywood) was conducted. Specifically considered were firms that started their operations around the same time with similar founding conditions, experiences, resources and technical competencies. Field observations and multiple rounds of in-depth interviews were conducted to achieve the research objectives.

The study found that firms adopted dominant or hybrid configurations when interacting with informality and formality. Dominant configurations represent the exclusive adoption of informal copyright practices while hybrid configurations refer to the blended use of informal and formal copyright practices. The second set of findings revealed that each firm’s strategic intent affected the type of interactional configuration that unfolded in the firm. Specifically, firms with social intents tended to adopt dominant configurations, whereas firms with socio-economic intents tended to adopt hybrid configurations.

The study implies that firms may profit from strategically focusing on when and in what circumstances to adopt informality. Strategic intents that blend social and economic rationales may secure more positive interactive outcomes from internal and external stakeholders promoting formality and informality.

This study highlights the fact that firms embedded in local religious and ethnic communities use organizational practices to solve social and institutional problems of their members. The copyright practices of these organizations encourage apprenticeship, youth empowerment and entrepreneurship in Nigeria.

To the best of the authors’ knowledge, this is the first study that goes beyond macro-level analysis to investigate the interactional dynamics between formality and informality at the firm, community, and state levels. The study is also first of its kind to use copyright practices as an analytical lens to explore the interaction between informality and formality.