David C. Whalley, Samjid H. Mannan and David J. Williams
Presents some experimental and theoretical results from research exploring the design rules and relevant process parameters in the assembly of electronic components using…
Abstract
Presents some experimental and theoretical results from research exploring the design rules and relevant process parameters in the assembly of electronic components using anisotropic conductive adhesive materials. The experimental configurations studies have geometries representative of flip‐chip and micro ball grid array chip scale packaging. Evaluates a range of materials combinations, including (random filled) adhesive materials based on both thermoplastic and thermo‐setting resin systems, combined with both glass reinforced polymer printed circuit board and silver palladium thick film on ceramic substrate materials. Also presents a summary of assembly experiments which have been conducted using a specially developed instrumented assembly system. This test rig allows the measurement of the process temperatures and pressures and their relationship with the consequent bondline thickness reduction and conductivity development. Finally summarizes the capabilities of models which have been developed of the assembly process and of the final joint properties.
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Ilse Valenzuela Matus, Jorge Lino Alves, Joaquim Góis, Paulo Vaz-Pires and Augusto Barata da Rocha
The purpose of this paper is to review cases of artificial reefs built through additive manufacturing (AM) technologies and analyse their ecological goals, fabrication process…
Abstract
Purpose
The purpose of this paper is to review cases of artificial reefs built through additive manufacturing (AM) technologies and analyse their ecological goals, fabrication process, materials, structural design features and implementation location to determine predominant parameters, environmental impacts, advantages, and limitations.
Design/methodology/approach
The review analysed 16 cases of artificial reefs from both temperate and tropical regions. These were categorised based on the AM process used, the mortar material used (crucial for biological applications), the structural design features and the location of implementation. These parameters are assessed to determine how effectively the designs meet the stipulated ecological goals, how AM technologies demonstrate their potential in comparison to conventional methods and the preference locations of these implementations.
Findings
The overview revealed that the dominant artificial reef implementation occurs in the Mediterranean and Atlantic Seas, both accounting for 24%. The remaining cases were in the Australian Sea (20%), the South Asia Sea (12%), the Persian Gulf and the Pacific Ocean, both with 8%, and the Indian Sea with 4% of all the cases studied. It was concluded that fused filament fabrication, binder jetting and material extrusion represent the main AM processes used to build artificial reefs. Cementitious materials, ceramics, polymers and geopolymer formulations were used, incorporating aggregates from mineral residues, biological wastes and pozzolan materials, to reduce environmental impacts, promote the circular economy and be more beneficial for marine ecosystems. The evaluation ranking assessed how well their design and materials align with their ecological goals, demonstrating that five cases were ranked with high effectiveness, ten projects with moderate effectiveness and one case with low effectiveness.
Originality/value
AM represents an innovative method for marine restoration and management. It offers a rapid prototyping technique for design validation and enables the creation of highly complex shapes for habitat diversification while incorporating a diverse range of materials to benefit environmental and marine species’ habitats.
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Abdul Quddus, Anwar Ul-Hamid and Huseyin Saricimen
– The purpose of this investigation was to evaluate the performance of high velocity oxy fuel (HVOF) coated SS-310 samples in a carburizing environment.
Abstract
Purpose
The purpose of this investigation was to evaluate the performance of high velocity oxy fuel (HVOF) coated SS-310 samples in a carburizing environment.
Design/methodology/approach
The carburization behavior of metallic coatings with three different compositions was studied under isothermal carburizing exposure conditions at 900°C for 125 hours. The coatings were deposited on SS 310 substrates using the HVOF technique. The ASTM Standard method was used to evaluate coating adhesion. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction and weight gain were used to evaluate the surface morphology, microchemical composition, phase constitution and degree of environmental protection imparted by the coatings.
Findings
The experimental results indicate that Ni-rich coating offered better protection to SS 310 alloy compared to Co-rich coatings in carburizing environments. This was thought to be due to the formation of a continuous protective layer of Cr2O3 on the Ni-rich coating surface.
Originality/value
The study has direct practical relevance to the petrochemical industry, particularly for refinery applications. In refinery service, SS310 is used in header damper plates. The useful service life of such header plates can be extended by the use of high temperature corrosion resistant metallic coatings. The present investigation highlighted the protection offered by Ni-based HVOF coated SS-310 samples in carburizing environment.
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P.K. Joshi, B. Gupta and P.S. Roy
The selection of wavelength region and number of bands is a research problem for remote sensing experts for utilization of data provided by the sensor system. The present study…
Abstract
Purpose
The selection of wavelength region and number of bands is a research problem for remote sensing experts for utilization of data provided by the sensor system. The present study proposes to make an evaluation for optimum band selection and classification accuracy.
Design/methodology/approach
The entropy, brightness value overlap index (BVOI), optimum index factor (OIF) and spectral separability analysis, i.e. Euclidean distance (ED), divergence, transformed divergence (TD) and Jefferies‐Matusita (JM) distance and accuracy of MLC classification were carried out. For the present study Terra ASTER, Landsat ETM+ and IRS 1D LISS III dataset has been used. The first three methods were for the spectral evaluation of the three satellite data used and for determination of information content, variance and spectral overlap among the classes present in the natural and man‐made landscape. The fourth method is for selection of spectral band combinations with highest separability of classes using divergence matrices. These band combinations are selected for the classification and subsequent accuracy assessment.
Findings
The OIF values are clearly indicating that the performance of ASTER data is the best, having the lowest correlation between the bands; hence the separability of the feature is also highest, while LISS III have shown high correlation between the bands, with the poor separability of the features. Landsat ETM+ data are in between these two sensors, better than LISS III but poorer than ASTER. The BVOI outputs of the three datasets of man‐made landscape show that band 3 of ASTER has the least overlap of the classes, followed by band 4 of ETM+. Very high overlap of the classes has been found in LISS III data. It has been found from spectral separability analysis of all the three datasets for the man‐made landscape that ASTER data with band combination of spectral bands 123468 contains the highest value of all the measures of spectral separability, i.e. ED (291.72), divergence (2,133.37), TD (2,000.00) and JM distance (1,414.10).
Research limitations/implications
It can be inferred from the present study that spectral resolution plays a very important role in discrimination of vegetation features. ASTER data which are with the highest number of the bands amongst the satellite data used had shown highest classification accuracy, while LISS III data with lowest number of bands had shown lowest accuracy, and Landsat ETM+ stood in between the two sensors.
Practical implications
It is important to evaluate the sensor systems and their spectral regions for discrimination of vegetation features. The number of bands present in a particular sensor and the spectral regions used in it are some of the crucial factors which decide the usefulness of the data for different applications, including vegetation‐related studies. The selection of spectral wavelength region, i.e. spectral bands and the sensor system, presents the research problem for remote sensing experts to suggest the best spectral regions and satellite sensor for the discrimination of the vegetation features in different landscapes, namely man‐made and natural.
Originality/value
In the present study all the three datasets are extensively examined and tested for their vegetation discrimination capabilities using well‐established methodologies. All the parameters applied on the datasets revealed that spectral resolution definitely plays a role in the performance of the data as far as discrimination of features is concerned both in natural and man‐made landscape with desirable accuracy.
H. Singh, D. Puri, S. Prakash and M. Srinivas
To characterise the high temperature oxide scales for some plasma sprayed NiCrAlY coated Ni‐ and Fe‐based superalloys.
Abstract
Purpose
To characterise the high temperature oxide scales for some plasma sprayed NiCrAlY coated Ni‐ and Fe‐based superalloys.
Design/methodology/approach
Ni‐22Cr‐10Al‐1Y metallic coatings were deposited on two Ni‐based superalloys; Superni 601 and Superni 718 and one Fe‐based superalloy; Superfer 800H by the shrouded plasma spray process. Oxidation studies were conducted on uncoated as well as plasma spray coated superalloys in air at 900°C under cyclic conditions for 50 cycles. Each cycle consisted of 1 h heating followed by 20 min of cooling in air. The thermogravimetric technique was used to approximate the kinetics of oxidation. X‐ray diffraction, SEM/EDAX and EPMA techniques were used to analyse the oxide scales.
Findings
All of the coated, as well as the uncoated, superalloys followed an alnost‐parabolic rate of oxidation. The NiCrAlY coating was found to be successful in maintaining its continuous contact with the superalloy substrates in all the cases. The oxide scales formed on the exposed NiCrAlY coated superalloys were found to be intact and spallation‐free. The main phases analysed for the coated superalloys were oxides of nickel, chromium and aluminium and spinel of nickel and chromium, which are expected to be useful for developing oxidation resistance at high temperatures.
Practical implications
The coated superalloys showed remarkable cyclic oxidation resistance under simulated laboratory conditions. However, it is suggested that these coated superalloys also should be tested in actual industrial environments of boilers and gas turbines, etc. so as to obtain more practical and reliable oxidation data.
Originality/value
The knowledge of the reaction kinetics and the nature of the surface oxide scales formed during oxidation is important for evaluating the alloys for their use and degradation characteristics in high temperature applications such as steam boilers, furnace equipment, heat exchangers and piping in chemical industry, reformer, baffle plates/tubes in fertilizer plants, jet engines, pump bodies and parts.
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Paul Smith, Nadia Crittenden and Peter Caputi
The purpose of this paper is to develop a new measure called the Career Pathways Survey (CPS) which allows quantitative comparisons of women's beliefs about glass ceilings.
Abstract
Purpose
The purpose of this paper is to develop a new measure called the Career Pathways Survey (CPS) which allows quantitative comparisons of women's beliefs about glass ceilings.
Design/methodology/approach
A 34‐item version of the CPS was completed by 243 women from all levels of management, mostly in Australia. An expanded 38‐item CPS was administered to another sample of women (n=307).
Findings
Analyses of data from both studies yielded a four factor model of attitudes to glass ceilings: resilience, acceptance, resignation and denial. The factors demonstrated good internal consistency.
Practical implications
The CPS allows a comparison of positive attitudes towards seeking promotions via resilience and denial scores, and provides feedback on negative attitudes towards seeking promotions via resignation and acceptance scores.
Social implications
This new measure can be recommended for studies of women's and men's attitudes towards gender inequality in organizational leadership. Also, it could play a role in identifying sexist cultures in organizations.
Originality/value
Because of the scarcity of measures of glass ceiling beliefs, this study makes a major contribution to the literature on women's beliefs about barriers to career advancement.
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– This paper aims to describe a case study of how an unexpected event created an opportunity to reconsider and rewrite the methodology chapter in the author’s PhD thesis.
Abstract
Purpose
This paper aims to describe a case study of how an unexpected event created an opportunity to reconsider and rewrite the methodology chapter in the author’s PhD thesis.
Design/methodology/approach
The approach that the author used that assisted her to change her methodology involved a combination of reflective and reflexive reading, thinking and writing. It was a slow and thorough process through which the author considered widely the choices that she was making. Through an iterative process of writing, reading and talking, and then re-writing, the author was able to establish a position or standpoint from which she felt confident about the underpinnings of her study.
Findings
The author came to understand herself ontologically in a new way. The author could see how she had moved significantly from a positivist view of static bodies of knowledge creation to a paradigm involving a more dynamic knowledge creation. Correspondingly, the author was able to revise and focus her methodology, and in the course of the process, she learnt and grew as a person and as a researcher. The author understood her values, assumptions and beliefs about the world much more clearly. The author also became much more aware of her own PhD journey, how she was developing personally and how her identity was evolving.
Originality/value
This paper will be useful for those who are embarking on their PhD journey and attempting to critique and/or rethink their methodological approach in the qualitative or interpretivist paradigm.
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Rebecca May Thompson, Bridie Victoria Stone and Philip John Tyson
Gypsy, Roma and Traveller (GRT) people within the UK and the Republic of Ireland are underrepresented within research and policies despite high rates of mental illness and…
Abstract
Purpose
Gypsy, Roma and Traveller (GRT) people within the UK and the Republic of Ireland are underrepresented within research and policies despite high rates of mental illness and suicide. This study aims to explore the mental health (MH) support needs for GRT people within the British Isles.
Design/methodology/approach
This study was a thematic analysis of semi-structured interviews with nine self-identified GRT people.
Findings
The analysis revealed a longing for acceptance, both within and outside the GRT community; barriers to help seeking, specifically unsuitable services, poor awareness, stigma and distrust; and increased vulnerability owing to participants’ perceived lack of prospects and adverse life events.
Originality/value
Despite increased vulnerability, MH services are underutilised by GRT people for a variety of cultural and practical reasons. To reduce the current inequality, it is imperative that services take steps to increase accessibility. This study expands upon previous research by using the voices of GRT people themselves, creating a narrative built from their own emic perspectives. Unlike previous research, this study focuses exclusively on the MH of participants and includes participants from across the British Isles.