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Article
Publication date: 21 August 2017

Xiaoming Zhang, Huilin Chen, Yanqin Ruan, Dongyu Pan and Chongchong Zhao

With the rapid development of materials informatics and the Semantic Web, the semantic-driven solution has emerged to improve traditional query technology, which is hard…

Abstract

Purpose

With the rapid development of materials informatics and the Semantic Web, the semantic-driven solution has emerged to improve traditional query technology, which is hard to discover implicit knowledge from materials data. However, it is a nontrivial thing for materials scientists to construct a semantic query, and the query results are usually presented in RDF/XML format which is not convenient for users to understand. This paper aims to propose an approach to construct semantic query and visualize the query results for metallic materials domain.

Design/methodology/approach

The authors design a query builder to generate SPARQL query statements automatically based on domain ontology and query conditions inputted by users. Moreover, a semantic visualization model is defined based on the materials science tetrahedron to support the visualization of query results in an intuitive, dynamic and interactive way.

Findings

Based on the Semantic Web technology, the authors design an automatic semantic query builder to help domain experts write the normative semantic query statements quickly and simply, as well as a prototype (named MatViz) is developed to visually show query results, which could help experts discover implicit knowledge from materials data. Moreover, the experiments demonstrate that the proposed system in this paper can rapidly and effectively return visualized query results over the metallic materials data set.

Originality/value

This paper mainly discusses an approach to support semantic query and visualization of metallic materials data. The implementation of MatViz will be a meaningful work for the research of metal materials data integration.

Details

International Journal of Web Information Systems, vol. 13 no. 3
Type: Research Article
ISSN: 1744-0084

Keywords

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Article
Publication date: 1 June 1983

John Martyn

This report describes the Crystallographic Data Centre, the Engineering Sciences Data Unit and the Mass Spectrometry Data Centre, under headings covering scope and general…

Abstract

This report describes the Crystallographic Data Centre, the Engineering Sciences Data Unit and the Mass Spectrometry Data Centre, under headings covering scope and general description, input acquisition and processing, outputs, distribution mechanisms, staff training and recruitment, user aspects, cost‐benefit considerations and future developments. It is based on information collected from published literature, extended interviews conducted at each centre, materials made available by the centres and a limited amount of telephone contact with users. The study was carried out between 17–28 January 1983, on behalf of the Office of Arts and Libraries, to provide input for the Library and Information Services Council Working Party on Centres of Information Excellence. Each of the three centres studied produces high‐quality specialised data, organised and validated to suit the requirements of specialist groups. All have been in existence for at least fifteen years, and all have enjoyed Government support at some time. Two are now profit‐seeking and one is non‐profit; one is university‐based, one is a private company and one is part of the Royal Society of Chemistry.

Details

Aslib Proceedings, vol. 35 no. 6
Type: Research Article
ISSN: 0001-253X

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Article
Publication date: 1 December 1990

SOUTHEND based airline Princess Air, a new carrier launched in April 1990, is now operating the world's first 9G rated commercial aircraft with role‐change capabilities …

Abstract

SOUTHEND based airline Princess Air, a new carrier launched in April 1990, is now operating the world's first 9G rated commercial aircraft with role‐change capabilities — a specifically converted British Aerospace BAe 146 QC four engined jetliner.

Details

Aircraft Engineering and Aerospace Technology, vol. 62 no. 12
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 16 November 2012

Mohammad Hadi Hafezi, N. Nik Abdullah, José F.O. Correia and Abílio M.P. De Jesus

Fatigue crack growth models based on elastic‐plastic stress‐strain histories at the crack tip region and strain‐life damage models have been proposed. The UniGrow model…

Abstract

Purpose

Fatigue crack growth models based on elastic‐plastic stress‐strain histories at the crack tip region and strain‐life damage models have been proposed. The UniGrow model fits this particular class of fatigue crack propagation models. The residual stresses developed at the crack tip play a central role in these models, since they are applied to assess the actual crack driving force. This paper aims to assess the performance of the UniGrow model based on available experimental constant amplitude crack propagation data, derived for several metallic materials from representative Portuguese bridges. It also aims to discuss key issues in fatigue crack growth prediction, using the UniGrow model, in particular the residual stress computation and the suitability of fatigue damage rules.

Design/methodology/approach

The UniGrow model is assessed using data derived by the authors for materials from Portuguese riveted metallic bridges. Strain‐life data, from fatigue tests on smooth specimens, are used to propose a convenient fatigue damage model. Predicted crack growth rates are compared with experimental crack propagation data obtained by authors using fatigue tests on compact tension specimens. Since the UniGrow model is a residual stress‐based propagation model, elastoplastic finite element analysis is proposed for comparison with the analytical approach implemented in the original UniGrow model.

Findings

The use of the Smith‐Watson‐Topper damage parameter overestimates the stress R‐ratio effects on crack propagation rates, mainly if the material shows crack propagation rates with small to moderate sensitivity to stress R‐ratio, which is the case of the materials under investigation in this paper. Alternatively, the application of the Coffin‐Manson damage law leads to consistent fatigue crack growth predictions for the investigated range of positive stress R‐ratios. The stress R‐ratios effects may be solely attributed to the residual stresses. Their estimation, using an analytical approach, may lead to inconsistent results, which is demonstrated by an alternative elastoplastic finite element analysis.

Originality/value

Contributions for more accurate predictions of fatigue crack propagation rates, for several stress ratios, using a strain‐based approach is proposed. This approach is valuable since it may be used to reduce the time consuming and costly fatigue crack propagation tests. Furthermore, the proposed approach shows potential for an unified crack initiation and propagation approach.

Details

International Journal of Structural Integrity, vol. 3 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 1 June 2000

A. Savini

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic…

Abstract

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

Details

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

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Article
Publication date: 19 August 2020

Paulo Cezar Vitorio Junior and Moacir Kripka

The fair wage potential (FWP) is a social assessment method that can serve as an important measure to estimate the related social impacts along a product's life cycle;…

Abstract

Purpose

The fair wage potential (FWP) is a social assessment method that can serve as an important measure to estimate the related social impacts along a product's life cycle; however, it does not admit a direct relation to the functional unit. This research presents the weighted fair wage potential (WFWP) method that relates the functional unit to the FWP. It is a simplified method to connect the material inventory to social data. This study aims to develop an approach to assess and choose the best construction typology for buildings based on the social sustainability of workers involved in the sectors.

Design/methodology/approach

The study is presented in phases. Phase 1 selected and identified two Brazilian house projects, which were considered for the following processes: extraction of raw materials, manufacture of building materials and housing construction. Phase 2 assembled the social life cycle inventories and executed them using the social life cycle assessment (SLCA). The inventory of materials followed the functional unit: “1.0 m² of the built housing”, and the social inventory observed data extracted from the National Household Sample Survey (PNAD). The study considered the stakeholder category “worker” and analysed the impact subcategory “fair salary”. The study also divided the social data into categories: worker gender, worker race/colour, worker union and worker formality to analyse the impact of subcategories: “equal opportunities/discrimination”, “freedom of association and collective bargaining” and “social benefits/social security”. Phase 3 compared the projects according to the results from the SLCA. The FWP considers the wage paid at supply chain sectors, and the WFWP relates the functional unit to the social data.

Findings

The results proved that the wages paid by the construction supply chain are fair. However, there are differences between the FWP of male and female workers, white and non-white workers, unionised and non-unionised workers and formal and informal workers. The study of the actual Brazilian minimum wage indicated that the FWP is sensitive to the reference wage to which the analysed wages paid are related. Considering the WFWP, the constructive typology employed in Project B can generate increased positive social impacts than Project A. The proposed study provides excellent results, and it can be adapted to different data to assess the social conditions of other countries and sectors.

Research limitations/implications

There is not enough primary data available for the variables real wages and real working time; for this reason, these variables received secondary data. Another limitation is the data used for the year range, since Brazilian microdata do not include years before 2002 and years beyond 2015.

Originality/value

The WFWP differs from the existing social sustainability studies because it relates the material information to social data; also, it defines the best option among the analysed alternatives, taking into consideration social sustainability, which enables the project design to go beyond technical aspects. The constructive typology and materials take into account the social sustainability of the construction supply chain, generating more sustainable projects and improving the circumstances of affected stakeholders.

Details

Engineering, Construction and Architectural Management, vol. 28 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

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Article
Publication date: 4 December 2017

Jifeng Ren, Rajib Ahmed and Haider Butt

The purpose of this paper is to analyse nanosecond pulsed laser ablation on both metallic materials and non-metallic materials; a comparison between metallic materials and…

Abstract

Purpose

The purpose of this paper is to analyse nanosecond pulsed laser ablation on both metallic materials and non-metallic materials; a comparison between metallic materials and non-metallic materials has also been included.

Design/methodology/approach

In this paper, FEM method has been used to calculate the result by means of the finite element method. Furthermore, all the analyses are based on thermal theories.

Findings

The paper presents a comparison of metallic and non-metallic materials. Besides, the effect of how laser parameter changes would influence the ablation depth has also been assessed.

Research limitations/implications

All studies in this paper are based on classical thermal theories. Thermal theories are not applicable some times.

Originality/value

With the results of this paper, suggestions are made so that experiments and manufactures could be optimised and improved.

Details

World Journal of Engineering, vol. 14 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

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Book part
Publication date: 21 May 2005

M. McAleer, Daniel Slottje and Pei Syn Wee

Abstract

Details

Patent Activity and Technical Change in US Industries
Type: Book
ISBN: 978-0-44451-858-3

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Article
Publication date: 10 December 2019

Xiaoming Zhang, Mingming Meng, Xiaoling Sun and Yu Bai

With the advent of the era of Big Data, the scale of knowledge graph (KG) in various domains is growing rapidly, which holds huge amount of knowledge surely benefiting the…

Abstract

Purpose

With the advent of the era of Big Data, the scale of knowledge graph (KG) in various domains is growing rapidly, which holds huge amount of knowledge surely benefiting the question answering (QA) research. However, the KG, which is always constituted of entities and relations, is structurally inconsistent with the natural language query. Thus, the QA system based on KG is still faced with difficulties. The purpose of this paper is to propose a method to answer the domain-specific questions based on KG, providing conveniences for the information query over domain KG.

Design/methodology/approach

The authors propose a method FactQA to answer the factual questions about specific domain. A series of logical rules are designed to transform the factual questions into the triples, in order to solve the structural inconsistency between the user’s question and the domain knowledge. Then, the query expansion strategies and filtering strategies are proposed from two levels (i.e. words and triples in the question). For matching the question with domain knowledge, not only the similarity values between the words in the question and the resources in the domain knowledge but also the tag information of these words is considered. And the tag information is obtained by parsing the question using Stanford CoreNLP. In this paper, the KG in metallic materials domain is used to illustrate the FactQA method.

Findings

The designed logical rules have time stability for transforming the factual questions into the triples. Additionally, after filtering the synonym expansion results of the words in the question, the expansion quality of the triple representation of the question is improved. The tag information of the words in the question is considered in the process of data matching, which could help to filter out the wrong matches.

Originality/value

Although the FactQA is proposed for domain-specific QA, it can also be applied to any other domain besides metallic materials domain. For a question that cannot be answered, FactQA would generate a new related question to answer, providing as much as possible the user with the information they probably need. The FactQA could facilitate the user’s information query based on the emerging KG.

Details

Data Technologies and Applications, vol. 54 no. 1
Type: Research Article
ISSN: 2514-9288

Keywords

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Article
Publication date: 7 December 2015

Nikolai Kashaev, Stefan Riekehr, Kay Erdmann, Alexandre Amorim Carvalho, Maxim Nurgaliev, Nikolaos Alexopoulos and Alexandra Karanika

Composite materials and metallic structures already compete for the next generation of single-aisle aircraft. Despite the good mechanical properties of composite materials

Abstract

Purpose

Composite materials and metallic structures already compete for the next generation of single-aisle aircraft. Despite the good mechanical properties of composite materials metallic structures offer challenging properties and high cost effectiveness via the automation in manufacturing, especially when metallic structures will be welded. In this domain, metallic aircraft structures will require weight savings of approximately 20 per cent to increase the efficiency and reduce the CO2 emission by the same amount. Laser beam welding of high-strength Al-Li alloy AA2198 represents a promising method of providing a breakthrough response to the challenges of lightweight design in aircraft applications. The key factor for the application of laser-welded AA2198 structures is the availability of reliable data for the assessment of their damage tolerance behaviour. The paper aims to discuss these issues.

Design/methodology/approach

In the presented research, the mechanical properties concerning the quasi-static tensile and fracture toughness (R-curve) of laser beam-welded AA2198 butt joints are investigated. In the next step, a systematic analysis to clarify the deformation and fracture behaviour of the laser beam-welded AA2198 four-stringer panels is conducted.

Findings

AA2198 offers better resistance against fracture than the well-known AA2024 alloy. It is possible to weld AA2198 with good results, and the welds also exhibit a higher fracture resistance than AA2024 base material (BM). Welded AA2198 four-stringer panels exhibit a residual strength behaviour superior to that of the flat BM panel.

Originality/value

The present study is undertaken on the third-generation airframe-quality Al-Li alloy AA2198 with the main emphasis to investigate the mechanical fracture behaviour of AA2198 BMs, laser beam-welded joints and laser beam-welded integral structures. Studies investigating the damage tolerance of welded integral structures of Al-Li alloys are scarce.

Details

International Journal of Structural Integrity, vol. 6 no. 6
Type: Research Article
ISSN: 1757-9864

Keywords

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