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Article
Publication date: 4 September 2017

Feng Liang, Quanyong Xu and Ming Zhou

The purpose of this paper is to propose a quasi-three-dimensional (3D) thermohydrodynamic (THD) model for oil film bearings with non-Newtonian and temperature-viscosity…

Abstract

Purpose

The purpose of this paper is to propose a quasi-three-dimensional (3D) thermohydrodynamic (THD) model for oil film bearings with non-Newtonian and temperature-viscosity effects. Its performance factors, including precision and time consumption, are investigated.

Design/methodology/approach

Two-dimensional (2D), 3D and quasi-3D numerical models are built. The thermal and mechanical behaviors of two types of oil film bearings are simulated. All the results are compared with solutions of commercial ANSYS CFX.

Findings

The 2D THD model fails to predict the temperature and pressure field. The results of the quasi-3D THD model coincide well with those of the 3D THD model and CFX at any condition. Compared with the 3D THD model, the quasi-3D THD model can greatly reduce the CPU time consumption, especially at a high rotational speed.

Originality/value

This quasi-3D THD model is proposed in this paper for the first time. Transient mechanical and thermal analyses of high-speed rotor-bearing system are widely conducted using the traditional 3D THD model; however, the process is very time-consuming. The quasi-3D THD model can be an excellent alternative with high precision and fast simulation speed.

Details

Industrial Lubrication and Tribology, vol. 69 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 May 2006

Slavenka Petrak and Dubravko Rogale

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

Abstract

Purpose

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

Design/methodology/approach

The method has been developed on an example of a 3D garment basic cut construction on a virtual body model, determining the position of characteristic 3D points necessary for computer‐based definition of 3D cutting pattern contour segments. Contour segments modelling, as well as the modelling of 3D cut surfaces has been done using the NURBS objects.

Findings

A 3D garment cut has been constructed, such that matches physical characteristics of the body in question and offers the necessary comfort of the cut. The surface of the 3D cut has been divided into individual 3D cutting patterns.

Research limitations/implications

The method has been developed on an example of a 3D garment basic cut construction of a single paper of clothing. However, the same principles can be applied and developed for any garment basic cut.

Practical implications

The 3D garment cut constructed can be further transformed into a network of polygons. Introducing fabric physical‐chemical properties fabric drape can be simulated, aiming at more realistic visualisation and further assessment of the garment fit. The 3D cutting patterns developed can be, applying computer‐based application of the mathematical models, transformed into 2D cutting patterns.

Originality/value

As compared to the methods developed by some previous investigations, the newly developed method offers the construction of garment 3D cut on a computer‐generated body model, granting the necessary comfort of the cut, which also means garment fitted to individual body characteristics. The 3D cut constructed can also be used as a starting point to define 2D cutting patterns in the following step, which will be matched to the physical characteristics of the model body, in the same way as the initial 3D cut.

Details

International Journal of Clothing Science and Technology, vol. 18 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

Content available
Article
Publication date: 14 May 2020

Nawel Lafioune and Michèle St-Jacques

This paper aims to create a new searchable 3D city model to help managers improve their decision-making.

Abstract

Purpose

This paper aims to create a new searchable 3D city model to help managers improve their decision-making.

Design/methodology/approach

This paper identifies data management basics and the key elements used in the new model design; it further analyzes five-city models, presents its findings and proposes analytical trends for the new model. It discusses the concepts underlying existing models, explains the benefit brought by the proposed model and demonstrates its robustness.

Findings

City systems can be interconnected, thanks to data digitization and the integration of new technologies into different management processes. Although there are several 3D city models available, none of those identified in this research can be queried for several sectors.

Research limitations/implications

This model design can only be successfully realized in the presence of a public mandate. Potential limitations include information security risks and political non-acceptance.

Originality/value

The present work proposes a searchable and high performance model having the distinctive capacity to bring together city systems and perform real-time data analysis in order to extract important information needed to guide the city, and in the context of a global vision.

Details

Innovation & Management Review, vol. 17 no. 3
Type: Research Article
ISSN: 2515-8961

Keywords

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Article
Publication date: 26 July 2013

Xuyuan Tao and Pascal Bruniaux

The study in this article aims to focus on a novel design concept of virtual 3D garment which is realized with the help of traditional patternmaking methodology and the…

Abstract

Purpose

The study in this article aims to focus on a novel design concept of virtual 3D garment which is realized with the help of traditional patternmaking methodology and the CAD softwares in order to directly conceive the virtual clothing on a mannequin morphotype in cyberspace in consideration of the ease allowance between the body shape and the garment.

Design/methodology/approach

The method of acquisition of 3D human body was explained at first. Then the process of creation of garment 3D model associated with the draping technique was presented. The superposition of patterns from the 3D modeling and the traditional method used in industries was done in order to visualize the right results. At last, the dynamic validation of the garment was carried out in order to analyze the fitting results of try‐on simulation.

Findings

The 3D modeling technique method based on the draping technique shows that the garment fits perfectly to the body shape of the wearer.

Social implications

For the ready‐to‐wear manufacture, this method can be also involved on the parametric mannequin in order to reduce the lifetime of development by eliminating the process of pattern grading in the future.

Originality/value

The originality of this article comes from the combination of the traditional draping technique with the advanced CAD softwares in consideration of the fitting and draping of the garment. This concept is used not only in the context of mass customized product but also in mass production for the ready‐to‐wear apparel industries. The patterns are directly adjusted in 3D and can immediately be tried on in 3D simulation. As a result, the process in 2D patternmaking design can be eliminated.

Details

International Journal of Clothing Science and Technology, vol. 25 no. 4
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 20 June 2016

Michael Groenendyk

The number of 3D models available on the internet to both students and educators is rapidly expanding. Not only are the 3D model collections of popular websites like…

Abstract

Purpose

The number of 3D models available on the internet to both students and educators is rapidly expanding. Not only are the 3D model collections of popular websites like Thingiverse.com growing, organizations such as the Smithsonian Institution and NASA have also recently begun to build collections of 3D models and make these openly accessible online. Yet, even with increased interest in 3D printing and 3D scanning technologies, little is known about the overall structure of the 3D models available on the internet. The paper aims to discuss this issue.

Design/methodology/approach

To initiate this project, a list was built of 33 of the most widely used 3D model websites on the internet. Freely downloadable models, as well as models available for purchase or as 3D printed objects were included in the list. Once the list of 33 websites was created, the data for each individual 3D model in the collections was manually assembled and recorded. The titles of the 3D models, keywords, subject headings, license information, and number of views and downloads were recorded, as this information was available. The data were gathered between January and May 2015, and compiled into a CSV database. To determine how online 3D model content relates to a variety of educational disciplines, relevant subject terms for a variety of educational disciples were extracted from the EBSCO database system. With this list of subject terms in hand, the keywords in the CSV database of model information were searched for each of the subject terms, with an automated process using a Perl script.

Findings

There have been many teachers, professors, librarians and students who have purchased 3D printers with little or no 3D modelling skills. Without these skills the owners of these 3D printers are entirely reliant on the content created and freely shared by others to make use of their 3D printers. As the data collected for this research paper shows, the vast majority of open 3D model content available online pertains to the professions already well versed in 3D modelling and Computer Aided Design design, such as engineering and architecture.

Originality/value

Despite that fact that librarians, teachers and other educators are increasingly using technologies that rely on open 3D model content as educational tools, no research has yet been done to assess the number of 3D models available online and what educational disciplines this content relates to. This paper attempts to fill this gap, providing an overview of the size of this content, the educational disciplines this content relates to and who has so far been responsible for developing this content. This information will be valuable to librarians and teachers currently working with technology such as 3D printers and virtual reality, as well as those considering investing in this technology.

Details

Library Hi Tech, vol. 34 no. 2
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 18 September 2019

Ahmad Shahrunnizam Ahmad Shazali and Khairul Nizam Tahar

The current technique used to measure construction is the conventional total station method. However, the conventional method is time-consuming and could not be used to…

Abstract

Purpose

The current technique used to measure construction is the conventional total station method. However, the conventional method is time-consuming and could not be used to create a photo-realistic three-dimensional (3D) model of an object. Furthermore, the Canseleri building is located at a slope. The paper aims to discuss this issue.

Design/methodology/approach

The aim of this study is to assess the geometric accuracy of a 3D model using unmanned aerial vehicle (UAV) images. There are two objectives in this study. The first is to construct a 3D model of the Canseleri building using UAV images. The second objective is to validate the 3D model of the Canseleri building based on actual measurements.

Findings

The close-range photogrammetry method, using the UAV platform, was able to produce a 3D building model. The results show that the errors between the actual measurement and the generated 3D model were less than 4 cm. The accuracy of the 3D model achieved in this study was about 0.015 m, compared to total station measurements.

Originality/value

Accuracy assessment was done by comparing the estimated measurement of the 3D model with the direct measurement. The differences between the measured values with actual values could be compared. Based on this study, the 3D building model gave a reliable accuracy for specific applications.

Details

International Journal of Building Pathology and Adaptation, vol. 38 no. 1
Type: Research Article
ISSN: 2398-4708

Keywords

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Article
Publication date: 11 June 2018

Zhijia Dong, Gaoming Jiang, Guoming Huang and Honglian Cong

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

International Journal of Clothing Science and Technology, vol. 30 no. 3
Type: Research Article
ISSN: 0955-6222

Keywords

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Article
Publication date: 3 May 2013

Hong Wang, Georgi Djambazov and Koulis Pericleous

The purpose of this paper is to describe how a 3D/1D transient heat transfer model has been developed for getting accurate thermal boundary conditions when investigating…

Abstract

Purpose

The purpose of this paper is to describe how a 3D/1D transient heat transfer model has been developed for getting accurate thermal boundary conditions when investigating the heat transfer in the TiAl castings and also for reducing the computational cost and simplifying the mesh generation.

Design/methodology/approach

Heat transfer in the mould is assumed to take place only in a direction perpendicular to the mould wall, called 1D heat transfer. The coordinates of cell centre and the temperature in the mould wall can be calculated by the model instead of meshing mould. Heat transfer in the mould is computed via the FD solution of a 1D heat transfer equation.

Findings

For some types of geometry, the model works very well. However, for some, which contain the geometric feature called “dead corner”, the model can't cover. There is some impact on the accuracy of the model.

Practical implications

In the casting industry, the geometry of the casting is usually very complex and contains different features. This leads to difficult meshing when using numerical model to predict the casting process. Furthermore, an accurate calculation is very important on the thermal boundary during filling and solidification, to support practice, to improve the process and minimise the casting defects.

Originality/value

In this paper, a novel method is developed to calculate the heat transfer through the casting‐mould interface to the mould wall in a casting.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 20 June 2016

Byounghyun Yoo, Heedong Ko and Sungkuk Chun

This paper aims to examine the changing backdrop of the consumer market in relation to three-dimensional (3D) printing, especially in the context of Web infrastructure…

Abstract

Purpose

This paper aims to examine the changing backdrop of the consumer market in relation to three-dimensional (3D) printing, especially in the context of Web infrastructure that connects consumers and producers with unprecedented diversity and scale and Web 2.0 user-created content in the material domain.

Design/methodology/approach

The paper presents a conceptual architecture and software platform that facilitates do-it-yourself reconfiguration of existing products incorporating 3D printing, mobile 3D sensor, augmented reality (AR) and Web technologies.

Findings

This work shows that prosumer reconfiguration of consumer products is the major paradigm in the era of democratized production. The results suggest that this approach may be used in the consumer market to meet consumer preferences for adopting innovations without redundant consumption.

Research limitations/implications

Verification of the proposed conceptual approach is limited to the use of household consumer products. A critical mass of participants and product information are both necessary to achieve a sustainable ecosystem from the proposed platform. Intellectual property issues rely on the fair use of end-user production in this paper.

Social implications

The proposed approach allows users to swap out consumer product parts or upgrade individual modules as innovations emerge, extending the lifecycles of consumer products and potentially reducing consumer waste.

Originality/value

There is a lack of work on facilitating the proliferation of practical 3D printing through prosumption in relation to existing consumer products. This paper’s scientific contribution involves how 3D printing affords social manufacturing and consumer-oriented presumption in conjunction with mobile 3D sensor, AR, and Web technologies.

Details

Rapid Prototyping Journal, vol. 22 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 1 June 2000

K. Wiak

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…

Abstract

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of over 13000