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1 – 10 of over 2000C.R. Leonardi, D.R.J. Owen and Y.T. Feng
The purpose of this paper is to present a novel computational framework based on the lattice Boltzmann method (LBM) and discrete element method (DEM) capable of simulating fines…
Abstract
Purpose
The purpose of this paper is to present a novel computational framework based on the lattice Boltzmann method (LBM) and discrete element method (DEM) capable of simulating fines migration in three dimensions. Fines migration occurs in a block cave mine, and is characterised by the faster movement of fine and often low‐grade material towards the draw point in comparison to larger, blocky material.
Design/methodology/approach
This study builds on the foundations and applications outlined in a companion paper, in which the non‐Newtonian LBM‐DEM framework is defined and applied in 2D simulations. Issues relevant to the extension to 3D, such as spatial discretisation, fluid boundary conditions and the definition of synthetic bulk material parameters using a power law model, are discussed.
Findings
The results of the 3D DEM percolation replication showed that migration is predominantly limited to within the draw zone, and that the use of a low‐cohesion material model resulted in a greater amount of fines migration. The draw sensitivity investigation undertaken with the two bell partial block cave analysis did not show a significant difference in the amount of migration, despite the two draw strategies being deliberately chosen to result in isolated and interactive draw of material.
Originality/value
Along with the companion paper, this paper presents a novel application of the developed non‐Newtonian LBM‐DEM framework in the investigation of fines migration, which until now has been limited to scale models, cellular automata or pure DEM simulations. The results highlight the potential for this approach to be applied in an industrial context, and indicate a number of potential avenues for further research.
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C.R. Leonardi, D.R.J. Owen and Y.T. Feng
The purpose of this paper is to present a novel computational framework capable of simulating the block cave phenomenon of fines migration in two dimensions. Fines migration is…
Abstract
Purpose
The purpose of this paper is to present a novel computational framework capable of simulating the block cave phenomenon of fines migration in two dimensions. Fines migration is characterised by the faster movement of fine and often low‐grade material towards the draw point in comparison to larger, blocky material. A greater understanding of the kinematic behaviour of fines and ore within the cave during draw is integral to the solution of this problem.
Design/methodology/approach
The lattice Boltzmann method (LBM) is employed in a nonlinear form to represent the fines as a continuum, and it is coupled to the discrete element method (DEM) which is used to represent large blocks. The issues relevant to this approach, such as fluid‐solid interaction, the synchronisation of explicit schemes, and the characterisation of a bulk material as a non‐Newtonian fluid are discussed.
Findings
Results of the 2D simulations reveal migration trends for the geometries, material properties and operational sequences analysed. By executing an extensive programme of numerical experiments the influence of these and other relevant block cave factors on the migration of fines could be isolated.
Originality/value
To the authors' knowledge, this is the first time the LBM has been used to simulate the flow of bulk materials. The non‐Newtonian LBM‐DEM framework is also a novel approach to the investigation of fines migration, which until now has been limited to scale models, cellular automata or pure DEM simulations. The results of the 2D migration analyses highlight the potential for this novel approach to be applied in an industrial context and also encourage the extension of the framework to 3D.
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The purpose of this research is to highlight issues relating to binder migration in traditional lime mortars and the potential consequences of this phenomenon. The paper focuses…
Abstract
Purpose
The purpose of this research is to highlight issues relating to binder migration in traditional lime mortars and the potential consequences of this phenomenon. The paper focuses on traditional mass masonry construction and will be of special interest to those surveying, maintaining and repairing historic ruinous structures and heavily exposed masonry bridges.
Design/methodology/approach
The paper draws on literature pertaining to the repair of traditional mass masonry structures and the somewhat limited science of binder dissolution and migration in saturated conditions. The paper also draws on the author's practical and academic knowledge of writing specifications for the repair of mass masonry structures and utilises examples of binder migration from several case study buildings.
Findings
The degree to which binder migration in traditional mortars occurs is little understood. It is, however, evident that migration of the binder occurs when saturated conditions are present and is exacerbated by prolonged moisture ingress. The effect of binder migration on the stability and performance of mass masonry structures is also little understood and requires greater attention. In addition, the nature of the repair mortars specified and the degree to which these materials have set will have a bearing on the potential for binder migration.
Originality/value
An assessment of binder migration in traditional lime mortars and its effect on the stability and performance of mass masonry structures has never previously been undertaken. This paper is the first to highlight the problem.
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This case study aims to demonstrate that in-house integrated library systems migration can be accomplished by a dedicated team of librarians without advanced tools or prior…
Abstract
Purpose
This case study aims to demonstrate that in-house integrated library systems migration can be accomplished by a dedicated team of librarians without advanced tools or prior experience with data migration or systems integration.
Design/methodology/approach
This migration was accomplished by academic librarians using freely available tools: OpenOffice Calc, MarcEdit and the Koha Integrated Library System.
Findings
The data migration pathway presented here was developed and successfully used to transfer over 48,000 records in less than two months.
Practical implications
This case study presents an original process that is particularly effective for smaller libraries.
Originality/value
While similar case studies exist, most employ expensive third-party contractors for data migration or rely heavily on institutional IT departments.
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The paper aims to explore the circumstances and processes involved in implementing and migrating from a proprietary integrated library system (ILS) (Follett’s Destiny) to an…
Abstract
Purpose
The paper aims to explore the circumstances and processes involved in implementing and migrating from a proprietary integrated library system (ILS) (Follett’s Destiny) to an open-source ILS (Koha) for a special focus institution.
Design/methodology/approach
In 2012, the campus libraries of God’s Bible College (GBC) migrated to Koha. After locally hosting and supporting Koha for three years, GBC contracted a vendor (ByWater Solutions) to provide hosting and support, beginning in the fall of 2015.
Findings
The paper offers experiences and practical recommendations in migration and implementation. The paper will demonstrate that libraries, including special-focus institutions, can migrate efficiently and without vendor support. Additionally, the paper examines some of the reasons why libraries might consider vendor hosting and support.
Practical implications
The paper gives libraries a framework, illustrated with a special-focus institution case study, for selecting and migrating from a proprietary ILS to an open-source ILS. Such information will be of assistance in clarifying the process of migration and implementation for institutions seeking to move from a proprietary system, especially Destiny, to an open-source ILS.
Originality/value
The paper covers the steps taken to successfully migrate the database and offers a series of best practices for the adoption and migration process of an open-source ILS, providing librarians and other key stakeholders both theoretical and practical information in the selection and implementation of an open-source ILS.
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This article addresses contemporary presentations of migrants, particularly women, as dependents and a ‘burden’ on welfare. Focusing mainly on Britain, it shows that, while…
Abstract
This article addresses contemporary presentations of migrants, particularly women, as dependents and a ‘burden’ on welfare. Focusing mainly on Britain, it shows that, while immigration policies increasingly restrict their access to official welfare, migrants are crucial to the provision of welfare both to their own family and community and in mainstream services, including professional roles as well as in informal employment. Migrants are involved in complex networks of caring relations, often across national boundaries, in which they may provide care to others in order to provide for dependents back home.
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Around 15% savings on freight costs, speedier packaging and elimination of dust contamination are claimed as a result of switching to Flo‐Pak free‐flow cushioning material as a…
Abstract
Around 15% savings on freight costs, speedier packaging and elimination of dust contamination are claimed as a result of switching to Flo‐Pak free‐flow cushioning material as a case infiller for their export packs, according to Croda Inks Ltd, of Colliers Wood, London. The company previously used traditional wood wool to protect tins of printing ink, packed in cases made up for export. This early method promoted dust problems for the packers who were supplied with protective face masks. It also contributed to high costs of maintaining cleanliness within the works and made it necessary to operate a vigilant control system to cope with fine dust migration, which inexplicably all too often found its way inside the tin containers to contaminate the ink contents. Flo‐Pak became the simple solution to these acute problems.
Lovanirina Ramboarison-Lalao, Chris Brewster and Pierre-Yves Boyer
The purpose of this paper is to explore the contextual determinants of transition from expatriation to migration (TEM) among ministers of religion originating from the developing…
Abstract
Purpose
The purpose of this paper is to explore the contextual determinants of transition from expatriation to migration (TEM) among ministers of religion originating from the developing world.
Design/methodology/approach
The authors used in-depth analysis of narratives of four African religious ministers working in France, plus interviews with their five superiors and three host country national colleagues.
Findings
The findings point to personal-level, organisational-level and country-level contextual determinants, which come into play as levers or barriers in the “TEM” process.
Originality/value
The study identifies a new category of global mobility research at the intersection of expatriation and migration and develops a theoretical framework which points to the positive and negative influence of three-layered contextual determinants on how expatriated low-status church ministers from the developing world become migrants. The authors found a so far unreported determinant of the personal context: the role of a world view: very visible as “God centrality” in the participants. Results also shed new light on the international careers of this overlooked category of “non-traditional expatriates” from Africa.
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Yangyiwei Yang, Patrick Kühn, Mozhdeh Fathidoost and Bai-Xiang Xu
Confronting the unveiled sophisticated structural and physical characteristics of permanent magnets, notably the samarium–cobalt (Sm-Co) alloy, This work aims to introduce a…
Abstract
Purpose
Confronting the unveiled sophisticated structural and physical characteristics of permanent magnets, notably the samarium–cobalt (Sm-Co) alloy, This work aims to introduce a simulation scheme that can link physics-based micromagnetics on the nanostructures and magnetostatic homogenization on the mesoscale polycrystalline structures.
Design/methodology/approach
The simulation scheme is arranged in a multiscale fashion. The magnetization behaviors on the nanostructures examined with various orientations are surrogated as the micromagnetic-informed hysterons. The hysteresis behavior of the mesoscale polycrystalline structures with micromagnetic-informed hysterons is then evaluated by computational magnetostatic homogenization.
Findings
The micromagnetic-informed hysterons can emulate the magnetization reversal of the parameterized Sm-Co nanostructures as the local hysteresis behavior on the mesostructures. The simulation results of the mesoscale polycrystal demonstrate that the demagnetization process starts from the grain with the largest orientation angle (a) and then propagates to the surrounding grains.
Research limitations/implications
The presented scheme depicts the demand for integrating data-driven methods, as the parameters of the surrogate hysteron intrinsically depend on the nanostructure and its orientation. Further hysteron parameters that help the surrogate hysteron emulate the micromagnetic-simulated magnetization reversal should be examined.
Originality/value
This work provides a novel multiscale scheme for simulating the polycrystalline permanent magnets’ hysteresis while recapitulating the nanoscale mechanisms, such as the nucleation of domains, and domain wall migration and pinning. This scheme can be further extended to simulate the part-level hysteresis considering the mesoscale features.
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Yanxia Zhang and Wei‐Jun. Jean Yeung
Asia's traditional experiences with care provision differ considerably from those of the West given the prevalent family‐based social norms about care and policies in this region…
Abstract
Purpose
Asia's traditional experiences with care provision differ considerably from those of the West given the prevalent family‐based social norms about care and policies in this region. In recent decades, Asia has experienced profound social and demographic transformations and is thus faced with significant challenges around care. However, care in Asian countries is a relatively less studied topic. There is an urgent need for a comparative study on recent policy and practice changes in care for the elderly and young children in different regions of Asia. The purpose of this special issue is to examine complicated boundary shift in care provision and financing between the state, market, community and family in East, Southeast and South Asia and to explore the implications of these changes in care policies and practices for social stratification by class and gender in Asia.
Design/methodology/approach
The introduction to this special issue gives an overview of the social and demographic transformations and new strains on care in Asia as a background and introduces the framework of welfare mix employed in this special issue, especially the concepts of social care and the welfare/care diamond.
Findings
The introduction summarizes the variations in regard to the governance and provision of care between different Asian countries and compares the differences in the state involvement between Asia and Europe.
Originality/value
The authors also discuss some of their contributions to methodological approaches and analytical frameworks in studying care and the implications of the current research for future studies.