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Article

Thomas Rowan and Mohammed Seaid

The purpose of this paper is to present a new numerical model for shallow water flows over heterogeneous sedimentary layers. It is already several years since the single…

Abstract

Purpose

The purpose of this paper is to present a new numerical model for shallow water flows over heterogeneous sedimentary layers. It is already several years since the single-layered models have been used to model shallow water flows over erodible beds. Although such models present a real opportunity for shallow water flows over movable beds, this paper is the first to propose a multilayered solver for this class of flow problems.

Design/methodology/approach

Multilayered beds formed with different erodible soils are considered in this study. The governing equations consist of the well-established shallow water equations for the flow, a transport equation for the suspended sediments, an Exner-type equation for the bed load and a set of empirical equations for erosion and deposition terms. For the numerical solution of the coupled system, the authors consider a non-homogeneous Riemann solver equipped with interface-tracking tools to resolve discontinuous soil properties in the multilayered bed. The solver consists of a predictor stage for the discretization of gradient terms and a corrector stage for the treatment of source terms.

Findings

This paper reveals that modeling shallow water flows over multilayered sedimentary topography can be achieved by using a coupled system of partial differential equations governing sediment transport. The obtained results demonstrate that the proposed numerical model preserves the conservation property, and it provides accurate results, avoiding numerical oscillations and numerical dissipation in the approximated solutions.

Originality/value

A novel implementation of sediment handling is presented where both averaged and separate values for sediment species are used to ensure speed and precision in the simulations.

Details

Engineering Computations, vol. 37 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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Article

W.J. Ready, S.R. Stock, G.B. Freeman, L.L. and L.J. Turbini

Under certain environmental conditions, printed wiring boards (PWBs) respond to applied voltages by developing sub‐surface deposits of copper salts extending from anode to…

Abstract

Under certain environmental conditions, printed wiring boards (PWBs) respond to applied voltages by developing sub‐surface deposits of copper salts extending from anode to cathode along separated fibre/epoxy interfaces. These deposits are termed conductive anodic filaments (CAFs) and, in this work, the dimensions and growth patterns of a CAF have been determined by serial sectioning. The CAF growth pathway is characterised and the spatial distribution of the copper salts is quantified with scanning electron microscopy (SEM) using backscattered electrons. The chemical composition of the CAF is determined using energy dispersive X‐ray analysis (EDS). Prior research using high‐resolution non‐destructive X‐ray microtomography is correlated with the serial sectioning data. The failure phenomenon known as CAF may pose serious long‐term reliability concerns in electronics applications exposed to adverse and hostile environments.

Details

Circuit World, vol. 21 no. 4
Type: Research Article
ISSN: 0305-6120

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Article

Felippe Fernandes and Cristiano Poleto

The purpose of this paper is to analyse the results of particle size profiles carried out in the dam Mãe d’água, located in the metropolitan region of Porto Alegre, Rio…

Abstract

Purpose

The purpose of this paper is to analyse the results of particle size profiles carried out in the dam Mãe d’água, located in the metropolitan region of Porto Alegre, Rio Grande do Sul, becoming a tool of support for geochemistry evaluation works of sediments in this basin.

Design/methodology/approach

The methodology comprised the particle size analysis of eight cores sampled using the extraction profile technique “Sampling Cores.” A total of 56 sub-samples were obtained at different depths, varying between 0 and 52 cm. The particle size analysis of the sub-samples was carried out with the protocol relating to Brazilian analysis standards NBR 7,181; for determination of the particle size distribution of thick sediments, the sieve method was used, and for fine sediments, the pipette method was used.

Findings

The results show that for the different depths, the sediment profiles show similarity in their sedimentary deposition layers. Cores T1, T6, T7 and T8 showed a classification with predominance of mud. Cores T2 and T5 showed variations throughout their sedimentary profile, varying of mud predominance to sand with gravel, and on cores T3 and T4, the predominant characteristic is sand with mud and sand with gravel, respectively.

Originality/value

It can be seen in this paper that energy of sedimentological flow reaches it in a different way, creating these three sectors (first, sand with gravel; second, sand with mud and third, mud) with different characteristics – morphodynamic and sedimentological. These characteristics are important for the study of the heavy metals on the soil and therefore for reducing the risk of contamination of water courses.

Details

Management of Environmental Quality: An International Journal, vol. 28 no. 4
Type: Research Article
ISSN: 1477-7835

Keywords

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Book part

Karl-Emanuel Dionne and Paul Carlile

Innovation challenges are increasingly complex, cutting across distributed actors from different disciplines, organizations, and fields. Solving such challenges requires…

Abstract

Innovation challenges are increasingly complex, cutting across distributed actors from different disciplines, organizations, and fields. Solving such challenges requires creating the capacities of opening up for innovation to access and develop a greater amount and variety of knowledge and resources. Perspectives on open source, open innovation, and interorganizational collaboration have explored such capacities, but from different origins and scopes of analysis. Our practice-based integrative framework of “opening innovation” helps highlight these differences and connect their relative strengths. Through a critical literature review paired with an analysis of different empirical cases from Hacking Health, a non-profit organization helping drive digital health innovation, the authors reveal the user-centric, firm-centric, and field-centric approaches to opening innovation that progressively connect a greater variety of actors and resources. The authors show how specific new relational practices they produce address the new relational dynamics these connections bring to accumulate more resources for innovation to keep progressing.

Details

Managing Inter-organizational Collaborations: Process Views
Type: Book
ISBN: 978-1-78756-592-0

Keywords

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Article

Haitao Wang, Jiayu Shen and Da Gao

Abutment damage in liquefied ground is an important form of seismic damage of bridge structure. This paper aims to further research the effect of beam restriction on…

Abstract

Purpose

Abutment damage in liquefied ground is an important form of seismic damage of bridge structure. This paper aims to further research the effect of beam restriction on seismic damage mode of abutment in liquefied ground.

Design/methodology/approach

Based on the investigation of the seismic damage of Shengli Bridge in Tangshan earthquake, the finite element software dynamic effective stress analysis for ground (UWLC) is used to simulate the seismic damage of Shengli Bridge, and the results were compared with the actual seismic damage results. Then, the influences of the horizontal binding force of the beam, the liquefaction layer thickness, the top weight of the abutment, the peak acceleration, the liquefaction layer buried depth and the type of the foundation soil on the abutment seismic damage model are studied.

Findings

The results show that numerical simulation results are consistent with the actual seismic damage, and it is feasible to use UWLC software to simulate seismic damage. The results show that the seismic failure mode of the gravity abutment in liquefied ground is slip–rotation coupling type, not single slip type or rotation type. The large deformation of abutment bottom layer, horizontal binding force of the beam and post-stage soil pressure are the main reasons for abutment rotation or even destruction.

Research limitations/implications

A series of basic assumptions are used in the calculation process in this paper. The gravity abutment is defined as the elastic body and neglects its local deformation. The soil layer is a homogeneous isotropic. The consolidation process and the drainage boundary problem are not considered in the calculation process. Therefore, the paper may have some limitations.

Originality/value

To further research the seismic damage mode and influencing factors of abutment in liquefied ground, in this paper, based on the investigation of the seismic damage of Shengli Bridge in Tangshan earthquake, the finite element software UWLC is used to simulate the seismic damage of Shengli Bridge, and the results were compared with the actual seismic damage results. The seismic damage mode and influencing factors of gravity abutment in liquefied ground have been studied.

Details

Journal of Engineering, Design and Technology, vol. 17 no. 1
Type: Research Article
ISSN: 1726-0531

Keywords

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Article

Nadjet Zair, Salah Chaab and Catherine Bertrand

The purpose of this paper is to assess the vulnerability of the aquifer using two models of analysis (DRASTIC and GOD) that were applied in practice in the regions of Bir…

Abstract

Purpose

The purpose of this paper is to assess the vulnerability of the aquifer using two models of analysis (DRASTIC and GOD) that were applied in practice in the regions of Bir Chouhada, Souk Naamane and Ouled Zouai in the district of Oum El-Bouaghi.

Design/methodology/approach

This study aims to determine the most adequate methods to ensure the protection of the Bir Chouhada, Souk Naamane and Ouled Zouai aquifer from pollution using vulnerability assessment. The application of the DRASTIC and GOD models made this evaluation possible.

Findings

The analysis of the both maps of vulnerability, resulting from the application of the two methods (DRASTIC and GOD), has revealed several classes of vulnerability that are no-, low-, medium- and high-vulnerable area. High DRASTIC vulnerability values vary between 145 and 178, and those of GOD vary between 0.07 and 0.57. It is observed that vulnerability increases from the center toward the eastern part of the plain; this is confirmed by the repartition of nitrate contents. The impact of the hydraulic conductivity on vulnerability to pollution is more significant than those of the vadose zone and the aquifer media. This is well observed when considering the single-parameter sensitivity analysis.

Originality/value

The text deepens the understanding of the vulnerability assessment and quality of the aquifer and the groundwater. The present study can be used for the assessment and the management of groundwater.

Details

Management of Environmental Quality: An International Journal, vol. 28 no. 3
Type: Research Article
ISSN: 1477-7835

Keywords

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Article

Major P.L. Teed

NOW that helium is exclusively used in the airships of the United States, whilst its employment in the craft of other Powers has been visualised by Dr. Eckener, it is…

Abstract

NOW that helium is exclusively used in the airships of the United States, whilst its employment in the craft of other Powers has been visualised by Dr. Eckener, it is interesting to examine the history, properties, occurrence, origin, extraction and practical utility of this most remarkable gas, whose discovery is both a romance and a defence, should it be required, of scientific as opposed to industrial research.

Details

Aircraft Engineering and Aerospace Technology, vol. 2 no. 9
Type: Research Article
ISSN: 0002-2667

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Article

Wenyuan Liu, Chunde Piao, Yazhou Zhou and Chaoqi Zhao

The purpose of this paper is to establish a strain prediction model of mining overburden deformation, to predict the strain in the subsequent mining stage. In this way…

Abstract

Purpose

The purpose of this paper is to establish a strain prediction model of mining overburden deformation, to predict the strain in the subsequent mining stage. In this way, the mining area can be divided into zones with different degrees of risk, and the prevention measures can be taken for the areas predicted to have large deformation.

Design/methodology/approach

A similar-material model was built by geological and mining conditions of Zhangzhuang Coal Mine. The evolution characteristics of overburden strain were studied by using the distributed optical fiber sensing (DOFS) technology and the predictive model about overburden deformation was established by applying machine learning. The modeling method of the predictive model based on the similar-material model test was summarized. Finally, this method was applied to engineering.

Findings

The strain value predicted by the proposed model was compared with the actual measured value and the accuracy is as high as 97%, which proves that it is feasible to combine DOFS technology with machine learning and introduce it into overburden deformation prediction. When this method was applied to engineering, it also showed good performance.

Originality/value

This paper helps to promote the application of machine learning in the geosciences and mining engineering. It provides a new way to solve similar problems.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

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Article

Brit Anak Kayan, Alan M. Forster and Phillip F.G. Banfill

Sustainability is well understood to encapsulate economic, environmental and societal parameters. The efficiency of maintenance interventions for historic buildings is no…

Abstract

Purpose

Sustainability is well understood to encapsulate economic, environmental and societal parameters. The efficiency of maintenance interventions for historic buildings is no exception and also conforms to these broad factors. Recently, environmental considerations for masonry repair have become increasingly important and this work supports this growing area. The purpose of this paper is to give insight on how an option appraisal approach of “Green Maintenance” modelling for historic masonry buildings repair practically determine and ultimately substantiate the decision-making process using a calculation procedures of life cycle assessment, within delineated boundaries.

Design/methodology/approach

Calculation procedures of the model enables an assessment of embodied carbon that is expended from different stone masonry wall repair techniques and scenarios for historic masonry buildings during the maintenance phase.

Findings

It recognises the importance roles Green Maintenance model can play in reducing carbon emissions and underpins rational decision making for repair selection.

Practical implications

It must be emphasised that the calculation procedures presented here, is not confined to historic masonry buildings and can be applied to any repair types and building form. The decisions made as a result of the utilisation of this model practically support environmentally focused conservation decisions.

Social implications

The implementation of the model highlights the efficacy of repairs that may be adopted.

Originality/value

The paper is a rigorous application and testing of the Green Maintenance model. The model relays the “true” carbon cost of repairs contextualised within the longevity of the materials and its embodied carbon that consequently allows rational appraisal of repair and maintenance options.

Details

Smart and Sustainable Built Environment, vol. 5 no. 2
Type: Research Article
ISSN: 2046-6099

Keywords

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Article

Michael Price, Charles Harvey, Mairi Maclean and David Campbell

The purpose of this paper is to answer two main research questions. First, the authors ask the degree to which the UK corporate governance code has changed in response to…

Abstract

Purpose

The purpose of this paper is to answer two main research questions. First, the authors ask the degree to which the UK corporate governance code has changed in response to both systemic perturbations and the subsequent enquiries established to recommend solutions to perceived shortcomings. Second, the authors ask how the solutions proposed in these landmark governance texts might be explained.

Design/methodology/approach

The authors take a critical discourse approach to develop and apply a discourse model of corporate governance reform. The authors draw together data on popular, corporate-political and technocratic discourses on corporate governance in the UK and analyse these data using content analysis and the historical discourse approach.

Findings

The UK corporate governance code has changed little despite periodic crises and the enquiries set up to investigate and make recommendation. Institutional stasis, the authors find, is the product of discourse capture and control by elite corporate actors aided by political allies who inhabit the same elite habitus. Review group members draw intertextually on prior technocratic discourse to create new canonical texts that bear the hallmarks of their predecessors. Light touch regulation by corporate insiders thus remains the UK approach.

Originality/value

This is one of the first applications of critical discourse analysis in the accounting literature and the first to have conducted a discursive analysis of corporate governance reports in the UK. The authors present an original model of discourse transitions to explain how systemic challenges are dissipated.

Details

Accounting, Auditing & Accountability Journal, vol. 31 no. 5
Type: Research Article
ISSN: 0951-3574

Keywords

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