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1 – 10 of over 2000
Article
Publication date: 2 January 2018

Jasgurpreet Singh Chohan, Rupinder Singh and Kamaljit Singh Boparai

This paper aims to focus on the changes in thermal and surface characteristics of acrylonitrile butadiene styrene (ABS) material when exposed to chemical vapours for surface…

Abstract

Purpose

This paper aims to focus on the changes in thermal and surface characteristics of acrylonitrile butadiene styrene (ABS) material when exposed to chemical vapours for surface finishing. The poor surface finish and the dimensional accuracy of the fused deposition modelling parts (of ABS material) because of the stair-stepping hinder their use for rapid tooling applications, which can be improved by vapour finishing process. The differential scanning calorimetry (DSC) tests are performed to investigate the thermal behaviour of ABS thermoplastic after vapour finishing.

Design/methodology/approach

The hip prosthesis replica has been used to highlight the efficacy of chemical finishing process for intricate and complex geometries. The replicas are treated with chemical vapours for different durations. The DSC tests are performed along with surface roughness, surface hardness and dimensional measurements of exposed replicas and compared with unexposed replica.

Findings

The longer finishing time, i.e. 20 s, manifested higher melting peak temperature, higher melting enthalpy and higher heat capacity along with smoother and harder surface as compared with unexposed replica. The finishing process enhanced the bonding strength and the heat-bearing capacity of ABS material. The vapour finishing process enhanced the thermal stability of the material which may extend its sustainability at higher temperatures.

Practical implications

The improved thermal stability of ABS thermoplastic after chemical vapour finishing has been demonstrated. This advancement allows the use of ABS in functional tooling suitable for small production runs with higher flexibility and lead time savings.

Originality/value

The heat effects associated with phase transitions as a function of temperature are studied in case of replicas finished with chemical vapours. The relationship between melting enthalpy and surface characteristics has been ascertained.

Details

Rapid Prototyping Journal, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 3 April 2009

Jehn‐Ruey Jiang, Chung‐Ta King, Chi‐Shiang Liao and Ching‐Hao Liu

The purpose of this paper is to propose MUREX, a mutable replica control scheme, to keep one‐copy equivalence for synchronous replication in structured peer‐to‐peer (P2P) storage…

Abstract

Purpose

The purpose of this paper is to propose MUREX, a mutable replica control scheme, to keep one‐copy equivalence for synchronous replication in structured peer‐to‐peer (P2P) storage systems.

Design/methodology/approach

For synchronous replication in P2P networks, it is proper to adopt crash‐recovery as the fault model; that is, nodes are fail‐stop and can recover and rejoin the system after synchronizing their states with other active nodes. In addition to the state synchronization problem, the paper identifies other two problems to solve for synchronous replication in P2P storage systems. They are the replica acquisition and the replica migration problems.

Findings

On the basis of multi‐column read/write quorums, MUREX conquers the problems by the replica pointer, the on‐demand replica regeneration, and the leased lock techniques.

Originality/value

The paper proves the correctness of MUREX, analyzes and also simulates it in terms of communication cost and operation success rate.

Details

International Journal of Pervasive Computing and Communications, vol. 5 no. 1
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 19 January 2010

Ihab El‐Katatny, S.H. Masood and Y.S. Morsi

Recent advancement in fused deposition modelling (FDM) rapid prototyping technology has made it a viable technology for application in reconstructive surgery. The purpose of this…

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Abstract

Purpose

Recent advancement in fused deposition modelling (FDM) rapid prototyping technology has made it a viable technology for application in reconstructive surgery. The purpose of this paper is to investigate the errors generated during the fabrication stage of complex anatomical replicas derived from computed tomography coupled with the technique of FDM.

Design/methodology/approach

An evaluation on the errors generated during the fabrication process of two anatomical parts (skull or mandible) for different human sizes (infant, female or male) is carried out. A comparison between the linear measurements of 11 landmarks on the virtual model of a skull and nine for the mandible of patient specific and its replica is conducted. Furthermore, eight landmarks are chosen to evaluate the bone thickness variation over the fabricated replicas.

Findings

Although the FDM technology proved the ability to manufacture and to fit prosthesis to a patient's unique proportions quickly and with relatively low cost, the model accuracy is a key factor to the applicability of such technology. The results show undersized replicas with an overall absolute average deviation of 0.24 per cent with an average standard deviation of 0.16 per cent of the skull models and 0.22 per cent with a 0.11 per cent standard deviation of the mandibles. Furthermore, a high level of accuracy is reflected in the representation of the measured bone thickness with deviations in the order of 100th of a millimetre being reported.

Originality/value

The paper demonstrates an outstanding accuracy using FDM process for the fabrication of anatomical replicas using models of different human sizes and gender in comparison to other established rapid prototyping techniques.

Details

Rapid Prototyping Journal, vol. 16 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 16 April 2018

Masoud Nosrati and Mahmood Fazlali

One of the techniques for improving the performance of distributed systems is data replication, wherein new replicas are created to provide more accessibility, fault tolerance and…

Abstract

Purpose

One of the techniques for improving the performance of distributed systems is data replication, wherein new replicas are created to provide more accessibility, fault tolerance and lower access cost of the data. In this paper, the authors propose a community-based solution for the management of data replication, based on the graph model of communication latency between computing and storage nodes. Communities are the clusters of nodes that the communication latency between the nodes are minimum values. The purpose of this study if to, by using this method, minimize the latency and access cost of the data.

Design/methodology/approach

This paper used the Louvain algorithm for finding the best communities. In the proposed algorithm, by requesting a file according to the nodes of each community, the cost of accessing the file located out of the applicant’s community was calculated and the results were accumulated. On exceeding the accumulated costs from a specified threshold, a new replica of the file was created in the applicant’s community. Besides, the number of replicas of each file should be limited to prevent the system from creating useless and redundant data.

Findings

To evaluate the method, four metrics were introduced and measured, including communication latency, response time, data access cost and data redundancy. The results indicated acceptable improvement in all of them.

Originality/value

So far, this is the first research that aims at managing the replicas via community detection algorithms. It opens many opportunities for further studies in this area.

Details

International Journal of Web Information Systems, vol. 14 no. 1
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 3 April 2009

Zakaria Maamar, Quan Z. Sheng, Samir Tata, Djamal Benslimane and Mohamed Sellami

In any critical system, high‐availability of software components like web services has so far been achieved through replication. Three replication strategies known as active…

Abstract

Purpose

In any critical system, high‐availability of software components like web services has so far been achieved through replication. Three replication strategies known as active, passive, and hybrid, describe for example how many replicas are needed, where to locate replicas, and how replicas interact with the original web service and among themselves if needed. The purpose of this paper is to show how replicates could be substituted with components that are similarly functional to the component that needs back‐up in case of failure.

Design/methodology/approach

After examination of the different existing replication strategies, it was decided to test the suitability of the proposed web services high‐availability approach based on communities for each strategy. To this end, the specification of web services using two behaviors, namely control and operational, was deemed appropriate.

Findings

The active replication strategy is the only strategy that could support the development of a web services high‐availability approach based on communities of web services.

Practical implications

The proposed approach has been validated in practice by deploying a JXTA‐based testbed. The experimental work has implemented the active replication strategy.

Originality/value

Software component high‐availability could be achieved by components that are similarly functional to this component, which permits the common limitations of existing replication strategies to be addressed.

Details

International Journal of Web Information Systems, vol. 5 no. 1
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 18 April 2017

Jasgurpreet Singh Chohan and Rupinder Singh

The purpose of this paper is to review the various pre-processing and post-processing approaches used to ameliorate the surface characteristics of fused deposition modelling…

2380

Abstract

Purpose

The purpose of this paper is to review the various pre-processing and post-processing approaches used to ameliorate the surface characteristics of fused deposition modelling (FDM)-based acrylonitrile butadiene styrene (ABS) prototypes. FDM being simple and versatile additive manufacturing technique has a calibre to comply with present need of tailor-made and cost-effective products with low cycle time. But the poor surface finish and dimensional accuracy are the primary hurdles ahead the implementation of FDM for rapid casting and tooling applications.

Design/methodology/approach

The consequences and scope of FDM pre-processing and post-processing parameters have been studied independently. The comprehensive study includes dominance, limitations, validity and reach of various techniques embraced to improve surface characteristics of ABS parts. The replicas of hip implant are fabricated by maintaining the optimum pre-processing parameters as reviewed, and a case study has been executed to evaluate the capability of vapour smoothing process to enhance surface finish.

Findings

The pre-processing techniques are quite deficient when different geometries are required to be manufactured within limited time and required range of surface finish and accuracy. The post-processing techniques of surface finishing, being effective disturbs the dimensional stability and mechanical strength of parts thus incapacitates them for specific applications. The major challenge for FDM is the development of precise, automatic and controlled mass finishing techniques with low cost and time.

Research limitations/implications

The research assessed the feasibility of vapour smoothing technique for surface finishing which can make consistent castings of customized implants at low cost and shorter lead times.

Originality/value

The extensive research regarding surface finish and dimensional accuracy of FDM parts has been collected, and inferences made by study have been used to fabricate replicas to further examine advanced finishing technique of vapour smoothing.

Details

Rapid Prototyping Journal, vol. 23 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 2 September 2019

Chi-cheung Choi

Studies of Tianhou-Mazu cult have been focused on three themes: studies in Taiwan emphasize hegemonic order; studies in Hong Kong reveal a relationship of “sisterhood” alliances;…

Abstract

Purpose

Studies of Tianhou-Mazu cult have been focused on three themes: studies in Taiwan emphasize hegemonic order; studies in Hong Kong reveal a relationship of “sisterhood” alliances; and studies in Singapore highlight the important role of ethnic groups. The rebuilding of the goddess’s ancestral temple in early 1980s and her acquiring a world intangible cultural heritage status in the early twenty-first century facilitate the redefinition of overseas Chinese’s religious affiliation. The purpose of this paper is to discuss this global development of the cult from the 1980s and its ritual implication in overseas Chinese communities.

Design/methodology/approach

This paper, by comparing the Tianhou-Mazu cult in Taiwan, Hong Kong and Southeast Asian Chinese settlements, argues that from sisters to descended replicas, or from local alliances to global hegemony, the cult of Tianhou-Mazu since the 1980s has not only replaced local culture with an emphasis on “high culture,” but also represents a religious strategy regarding local people’s interpretation of correctness and authority.

Findings

This paper argues that despite the imposition of hegemonic power from various authorities, popular religion is a matter of choice. This reflects how local religious practice is construed according to the interpretation of global cultural languages by the elite Chinese; their decision of when and how to reconnect with the goddess’s ancestral temple or the “imperial state,” or to form alliances with other local communities; and the implementation of the local government’s cultural policy.

Originality/value

This paper is one of the few attempts comparing development of a folk cult in various communities.

Details

Asian Education and Development Studies, vol. 9 no. 1
Type: Research Article
ISSN: 2046-3162

Keywords

Article
Publication date: 16 October 2018

Kristy Henson, Paul Constantino, F. Robin O’Keefe and Greg Popovich

The topic of human skeletal analysis is a sensitive subject in North America. Laws and regulations surrounding research of human skeletal material make it difficult to use these…

3010

Abstract

Purpose

The topic of human skeletal analysis is a sensitive subject in North America. Laws and regulations surrounding research of human skeletal material make it difficult to use these remains to characterize various populations. Recent technology has the potential to solve this dilemma. Three-dimensional (3D) scanning creates virtual models of this material, and stores the information, allowing future studies on the material. The paper aims to discuss these issues.

Design/methodology/approach

To assess the potential of this methodology, the authors compared processing time, accuracy and costs of computer tomography (CT) scanner to the Artec Eva portable 3D surface scanner. Using both methodologies the authors scanned and 3D printed one adult individual. The authors hypothesize that the Artec Eva will create digital replicas of <5 percent error based on Buikstra and Ubelaker standard osteometric measurements. Error was tested by comparing the measurements of the skeletal material to the Artec data, CT data and 3D printed data.

Findings

Results show that larger bones recorded by the Artec Eva have <5 percent error of the original specimen while smaller more detailed images have >5 percent error. The CT images are closer to <5 percent accuracy, with few bones still >5 percent error. The Artec Eva scanner is inexpensive in comparison to a CT machine, but takes twice as long to process the Eva’s data. The Artec Eva is sufficient in replication of larger elements, but the CT machine is still a preferable means of skeletal replication, particularly for small elements.

Originality/value

This research paper is unique because it compares two common forms of digitization, which has not been done. The authors believe this paper would be of value to natural history curators and various researchers.

Details

Library Hi Tech, vol. 37 no. 3
Type: Research Article
ISSN: 0737-8831

Keywords

Article
Publication date: 3 May 2013

Karen Miller

Very little fast fashion literature focuses on pleasure‐seeking activities or luxury‐fast‐fashion and the purpose of this paper is to start addressing these gaps from the…

10572

Abstract

Purpose

Very little fast fashion literature focuses on pleasure‐seeking activities or luxury‐fast‐fashion and the purpose of this paper is to start addressing these gaps from the perspective of the customer.

Design/methodology/approach

Over eight months, a naturalistic inquiry obtained publicly available online information from customers who during their normal daily lives freely shared their opinions and reflections about fast fashion purchases.

Findings

A clearly apparent and unexpected finding is that pleasure‐seeking consumers enjoy creativity associated with ephemeral fashions and uniqueness, as these add value to the customer in different ways, depending on whether the customer is a fast fashion or a replica customer.

Research limitations/implications

This study is limited to the fast fashion context and lays the foundation for future researchers to consider other contexts of fashion or luxury brands to qualify or quantify the extent of pleasure seeking and its contribution to the fashion experience in the context of the designer, the fashion brand and the customer.

Practical implications

Developing fashion games or fashion applications that enable the user to create and design fashion items, or mix and match fashion items will reinforce enjoyment in the design experience and linking these to the brand should reinforce positive affirmations toward the fast fashion brand.

Originality/value

This paper takes a fresh approach to uncover and describe hedonic customer responses to replica and fast fashion, the results of which update fast fashion and the luxury brand literatures and demonstrate the importance of creativity in the experience.

Details

Journal of Fashion Marketing and Management: An International Journal, vol. 17 no. 2
Type: Research Article
ISSN: 1361-2026

Keywords

Article
Publication date: 18 October 2019

A. Abdollahi Nami and L. Rajabion

A mobile ad hoc network (MANET) enables providers and customers to communicate without a fixed infrastructure. Databases are extended on MANETs to have easy data access and…

Abstract

Purpose

A mobile ad hoc network (MANET) enables providers and customers to communicate without a fixed infrastructure. Databases are extended on MANETs to have easy data access and update. As the energy and mobility limitations of both servers and clients affect the availability of data in MANETs, these data are replicated. The purpose of this paper is to provide a literature review of data replication issues and classify the available strategies based on the issues they addressed.

Design/methodology/approach

The selected articles are reviewed based on the defined criteria. Also, the differences, the advantages and disadvantages of these techniques are described. The methods in the literature can be categorized into three groups, including cluster-based, location-based and group-based mechanisms.

Findings

High flexibility and data consistency are the features of cluster-based mechanisms. The location-based mechanisms are also appropriate for replica allocation, and they mostly have low network traffic and delay. Also, the group-based mechanism has high data accessibility compared to other mechanisms. Data accessibility and time have got more attention to data replication techniques. Scalability as an important parameter must be considered more in the future. The reduction of storage cost in MANETs is the main goal of data replication. Researchers have to consider the cost parameter when another parameter will be influenced.

Research limitations/implications

Data replication in MANETs has been covered in different available sources such as Web pages, technical reports, academic publications and editorial notes. The articles published in national journals and conferences are ignored in this study. This study includes articles from academic main international journals to get the best capability.

Originality/value

The paper reviews the past and the state-of-the-art mechanisms in data replication in MANET. Exclusively, data replication’s main goal, existing challenges, research terminologies and mechanisms in MANET are summarized using the answers to the research questions. This method will help researchers in the future to develop more effective data replication method in MANET.

Details

International Journal of Pervasive Computing and Communications, vol. 15 no. 3/4
Type: Research Article
ISSN: 1742-7371

Keywords

1 – 10 of over 2000