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The purpose of this paper is to implement and test a 1D eddy‐current model for laminated iron core of electrical machines and investigate the possibility of incorporating it in a 2D FE analysis.

The 1D eddy‐current model of laminated core is extended to handle rotating‐field problems and coupling between the x‐ and y‐components of the magnetic field. Explicit coupling terms are introduced in the Jacobean matrix to ensure convergence and time efficiency. The procedure is computationally tested for both the case where there is no feedback to the 2D FE and the case where the results of the eddy‐current model were fed‐back to the 2D analysis.

The coupling terms ensured fast and robust convergence. The incorporation of the eddy‐current model in the 2D FE analysis is possible, provided some under‐relaxation is used to ensure the convergence of the overall 1D‐2D procedure.

The method has been computationally tested with 2D like procedure corresponding to a 2D model with only one element. The behaviour of the model in actual 2D computation presents some problems related to the convergence of the overall procedure and they have been dealt with in another publication.

The paper is of practical value for designers of electrical machines. On one hand, the model can be used a posteriori to estimate eddy‐current losses in iron stacks, and on the other hand it can be incorporated into 2D FE analysis including the losses in the field solution and enhancing its power and energy balance.

The purpose of this paper is to evaluate the impact of visual models on the ability of construction students to assess design buildability.

The study engaged 45 construction students from one selected tertiary education institute in New Zealand. The data collection process involved meeting the students face-to-face and demonstrating the VR model to them, after which the students completed an online questionnaire and assessed design buildability using both 2D drawing and virtual reality (VR) models. To make this assessment, the participants considered a residential earth building modelled to promote sustainable building features. The assessment process required the participants to evaluate the design buildability of the same building design using a 2D drawing and a 3D VR model.

The study found that VR models have significant advantages for assessing design buildability. Students measured 16.80% higher average buildability with the 3D VR model compared to the 2D drawing. The participants in the evaluation felt that the visual model significantly improved the comprehensibility of complex designs, which helped identify and manage design buildability (overall, 83% of participants strongly supported this).

The paper showed construction digitisation such as VR, augmented reality and building information modelling is highly cooperative as it can easily be made available for online learning. Thus, the findings support construction educators use online-based VR learning to promote efficient teaching of design buildability to students.

This paper aims to compare and study two-dimensional (2D) and three-dimensional (3D) computational fluid dynamics simulation results of gas flow velocity in a convection reflow oven and show the differences of the different modeling aspects. With the spread of finer surface-mounted devices, it is important to understand convection reflow soldering technology more deeply.

Convection reflow ovens are divided into zones. Every zone contains an upper and a lower nozzle-matrix. The gas flow velocity field is one of the most important parameters of the local heat transfer in the oven. It is not possible to examine the gas flow field with classical experimental methods due to the extreme circumstances in the reflow oven. Therefore, numerical simulations are necessary.

The heat transfer changes highly along the moving direction of the assembly, and it is nearly homogeneous along the traverse direction of the zones. The gas flow velocity values of the 2D model are too high due to the geometrical distortions of the 2D model. On the other hand, the calculated flow field of the 2D model is more accurate than in the 3D model due to the finer mesh.

Investigating the effects of tall components on a printed wiring board inside the gas flow field and further analysis of the mesh size effect on the models.

The presented results can be useful during the design of a simulation study in a reflow oven (or in similar processes).

The presented results provide a completely novel approach from the aspect of 2D and 3D simulations of a convection reflow oven. The results also reveal the heat transfer differences.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

Accurate presentation of the rock microstructure is critical to the grain-scale analysis of rock deformation and failure in numerical modelling. 3D granite microstructure modelling has only been used in limited studies with the mineral pattern often remaining poorly constructed. In this study, the authors developed a new approach for generating 2D and 3D granite microstructure models from a 2D image by combining a heterogeneous material reconstruction method (simulated annealing method) with Voronoi tessellation.

More specifically, the stochastic information in the 2D image is first extracted using the two-point correlation function (TPCF). Then an initial 2D or 3D Voronoi diagram with a random distribution of the minerals is generated and optimised using a simulated annealing method until the corresponding TPCF is consistent with that in the 2D image. The generated microstructure model accurately inherits the stochastic information (e.g. volume fraction and mineral pattern) from the 2D image. Lastly, the authors compared the topological characteristics and mechanical properties of the 2D and 3D reconstructed microstructure models with the model obtained by direct mapping from the 2D image of a real rock sample.

The good agreements between the mapped and reconstructed models indicate the accuracy of the reconstructed microstructure models on topological characteristics and mechanical properties.

The newly developed reconstruction method successfully transfers the mineral pattern from a granite sample into the 2D and 3D Voronoi-based microstructure models ready for use in grain-scale modelling.

This paper aims to model a three-dimensional twisted geometry of a twisted pair studied in an electrostatic approximation using only two-dimensional (2D) finite elements.

The proposed method is based on the reformulation of the weak formulation of the electrostatics problem to deal with twisted geometries only in 2D.

The method is based on a change of coordinates and enables a faster computational time as well as a high accuracy.

The effectiveness of the adopted approach is demonstrated by studying different configurations related to the IEC 60851-5 standard defined for the measurement of the electrical properties of the insulation of the winding wires used in electrical machines.

The purpose of this paper is to propose an interactive 2D–3D garment parametric pattern-making and linkage editing scheme that integrates clothing design, simulation and interaction to design 3D garments and 2D patterns. The proposed scheme has the potential to satisfy the individual needs of fashion industry, such as precise fit evaluation of the garment, interactive style editing with ease allowance and constrained contour lines in fashion design.

The authors first construct a parametric pattern-making model for flat pattern design corresponding to the body dimensions. Then, the designing 2D patterns are stitched on a virtual 3D mannequin by performing a virtual try-on. If the customer is unsatisfied after the virtual try-on, the adjustable parameters (appearance parameters and fit parameters) can be adjusted using the 2D–3D linkage editing with hierarchical constrained contour lines, and the fit evaluation tool interactively provides the feedback.

The authors observed that the usability and efficiency of the existing garment pattern-making method simplifies the garment pattern-making process. The authors utilize an interactive garment parametric flat pattern-making model to generate an individualized garment flat pattern that effectively adjust and realize the local editing of the garment pattern-making. The 2D–3D linkage editing is then employed, which alters the size and shape of garment pattern for a precise human model fit of the 3D garment using hierarchical constrained contour lines. Various instances have validated the effectiveness of the proposed scheme, which can increase the reusability of the existing garment styles and improve the efficiency of fashion design.

First, the authors do not consider the garment pattern-making design of sophisticated styles. Second, the authors do not directly consider complex garment shapes such as wrinkles, folds, multi-layer models and fabric physical properties.

The authors propose a pattern adjustment scheme that uses the 3D virtual try-on technology to avoid repetitions of reality-based fit tests and garment sample making in the designing process of clothing products. The proposed scheme provides interactive selections of garment patterns and sizes and renders modification tools for 3D garment designing and 2D garment pattern-making. The authors present the 2D–3D interactive linkage editing scheme for a custom-fit garment pattern based on the hierarchical constraint contour lines. The spatial relationship among the human body, pattern pieces and 3D garment model is adequately expressed, and the final design result of the garment pattern is obtained by constraint solving. Meanwhile, the tightness tension of different parts of the 3D garment is analyzed, and the fit and comfort of the garment are quantitatively evaluated.

The purpose of this paper is to analyse the accuracy of the thrust force of a linear actuator computed with different finite elements models.

A series of 2D and 3D models corresponding to different levels of approximation of the original problem are considered. A reliable error estimator based on dual magnetostatic formulations is used.

A 3D model does not necessarily ensure more accurate results than a 2D model. Because of limitations on the number of mesh elements, the discretisation error in 3D can be of the same order of magnitude as the error introduced by the 2D approximation.

The results emphasise the need to consider errors arising from different simplifications with respect to one another, in order to avoid improvements of the model increasing the complexity but not improving the accuracy of the results.

The virtual display of 3D garment is one of the most important features in a computer-aided garment design system. The purpose of this paper is to present a novel web-based 3D virtual display framework for the online design of warp-knitted seamless garment using the latest WebGL and HTML5 technologies.

Based on the feature-based parametric 3D human body model, the 3D model of skin-tight warp-knitted seamless garment is established using the geometric modeling method. By applying plane parameterization technology, the 3D garment model is then projected into corresponding 2D prototype pattern and a texture-mapping relationship is obtained. Finally, an online 3D virtual display application framework for warp-knitted seamless garment is implemented on modern WebGL-enabled web browsers using the latest WebGL and HTML5 technologies, which allow garment designers to globally access without installing any additional software or plugin.

Based on the 2D/3D model of warp-knitted seamless garment, an online 3D virtual display application running on modern WebGL-enabled web browser is implemented using the latest Javascript, WebGL and HTML5 technologies, which is proven to be an effective way for building the web-based 3D garment CAD systems.

This paper provides a parametric design method for warp-knitted seamless garment 2D/3D model, and web-based online virtual display of 3D warp-knitted seamless garment is implemented for the first time, which establishes the foundation for the web-based online computer-aided warp-knitted seamless garment design system.

Simple discrete element models using PFC^2D models with bonded assemblies of particles were used to numerically simulate direct tension and block punching tests on thin spray‐on tunnel liner materials to gain insight about the liner support mechanisms. PFC^2D input parameters were calibrated such that the rupture load and elongation at rupture were similar to the laboratory test data. The calibrated model of the liner material was then used to simulate a liner around a highly stressed tunnel in rock where stresses caused extensive fracturing near the top of the tunnel. The effect of the liner was analysed by modelling the tunnel with and without the liner and showed that the liner had minimal impact on fracture propagation in the rock because of the liner's highly deformable nature. However, the liner was able to retain the fractured rock in place.