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1 – 10 of over 3000
Article
Publication date: 1 February 1995

G.M. Wenger, D.A. Machusak and J.L. Parker

Organic solderability preservative (OSP) coatings are not new. They have been used successfully with aggressive water soluble flux for assembly of through‐hole only PWBs. However…

Abstract

Organic solderability preservative (OSP) coatings are not new. They have been used successfully with aggressive water soluble flux for assembly of through‐hole only PWBs. However, the multiple heating cycles required for mixed technology assembly and use of no‐clean low solids flux (LSF) for wave solder assembly have placed a greater demand on the solderability protection provided by OSPs. Wetting balance and float testing were used to evaluate numerous OSPs as well as the potential for these surface finishes to be used for ‘No‐Clean’ assembly. Although these laboratory evaluations revealed that OSPs are not as robust as SnPb, they did indicate the assembly processes and materials which could work with OSPs. Additional simulated assembly trials with test vehicles confirmed that thick OSP pre‐flux coatings interfere with soldering and that the solderability of surfaces with thin OSPs degrades when heated in an air environment. Since none of the OSPs evaluated outperformed the imidazole currently in use at AT&T, a no‐clean LSF assembly production trial with a mixed technology telecommunication circuit pack was conducted to compare imidazole with hot air solder levelled surfaces. The production trial and laboratory evaluations resulted in the development of an application model. The elements of the application model are not complicated: (1) use thin OSPs, (2) avoid baking, (3) use as aggressive a flux as possible, (4) apply as much flux as possible, (5) apply the flux where you want solder to wet, and (6) use nitrogen inerted processes whenever possible. Combination of these elements has led to the successful implementation of OSPs for no‐clean assembly. Funding for this effort was obtained through the National Center for Manufacturing Sciences (NCMS) Printed Wiring Board Interconnect Program.

Details

Soldering & Surface Mount Technology, vol. 7 no. 2
Type: Research Article
ISSN: 0954-0911

Book part
Publication date: 20 November 2015

Sharon M. Peck

This chapter addresses the outcomes of a six-year school–university partnership between a public liberal arts college and a large urban school district. It explores ways that…

Abstract

This chapter addresses the outcomes of a six-year school–university partnership between a public liberal arts college and a large urban school district. It explores ways that partnerships can support teachers and communities to confront assumptions and take ownership of learning. This paper traces the trajectory of teachers and professors engaged in a longitudinal ongoing professional development initiative focused on “Meeting the Needs of Urban Learners” to identify practices that supported the collaboration, and the outcomes of the school–university partnership.

Details

University Partnerships for Community and School System Development
Type: Book
ISBN: 978-1-78560-132-3

Article
Publication date: 1 February 1993

I. Artaki, U. Ray, H.M. Gordon and R.L. Opila

The emergence of new interconnection technologies involving double‐sided surface mounted components has put stronger restrictions on the method of preserving the solderable finish…

Abstract

The emergence of new interconnection technologies involving double‐sided surface mounted components has put stronger restrictions on the method of preserving the solderable finish on printed circuit (PC) boards. The popular Sn/Pb coatings have come under strong scrutiny due to environmental hazards of lead and also because they do not provide flat, planar surfaces for SM assembly. Organic solderability preservative coatings (OSP) are emerging as strong contenders for replacing Sn/Pb surface finishes. Benzotriazole based organic coatings have been successfully used in the past by several electronics manufacturers. However, assembly technologies involving multiple thermal operations have necessitated a fundamental understanding of the thermal stabilities and the mechanism of corrosion protection provided by the OSPs. This paper reports the results of an investigation of the thermal stabilities of two organic corrosion protection coatings. Although both are organic azole based, they operate in two distinct regimes: one forming thin films (∼100 Å) and the other forming thick films (∼5000 Å). The mechanism of surface protection has been studied using direct surface analytical techniques such as X‐ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), scanning transmission electron microscopy (SEM/TEM) and Fourier transform infrared spectroscopy (FT‐IR). The solderability of the copper was measured by wetting balance techniques and correlated to the amount of copper oxidation. The results indicate that, although the thin films provide excellent protection for storage and handling operations, they decompose under heat, thereby causing oxidation of the copper. The thick films appear to withstand multiple thermal cycling. However, the underlying copper substrate can still be oxidised by oxygen diffusion through pores or cracks, or the film may undergo chemical changes that render the copper unsolderable.

Details

Circuit World, vol. 19 no. 3
Type: Research Article
ISSN: 0305-6120

Book part
Publication date: 13 September 2017

Ziqiang Han and William L. Waugh

This chapter provides the foundation for the book. The objective of this chapter is to outline the theme of the book and to provide the context for the chapters that follow…

Abstract

This chapter provides the foundation for the book. The objective of this chapter is to outline the theme of the book and to provide the context for the chapters that follow. Disaster recovery is a challenge for governments and for affected communities, families, and individuals. It is a challenge, because recovery from catastrophic disasters can be much more complicated and elusive than what can be addressed by national and international aid organizations given the time and other resources. The short literature review provides the research context, and the overview of the book describes each of the chapters briefly.

Details

Recovering from Catastrophic Disaster in Asia
Type: Book
ISBN: 978-1-78635-296-5

Keywords

Article
Publication date: 1 February 1990

G.M. Wenger, L.A. Guth and D.A. Dickinson

Non‐corrosive rosin fluxes have historically been used for telephone communications assemblies because they provide a measure of reliability even if the flux is not totally…

Abstract

Non‐corrosive rosin fluxes have historically been used for telephone communications assemblies because they provide a measure of reliability even if the flux is not totally removed from the assembly. While cleaning is not always necessary from a reliability standpoint, testing issues, product appearance, operating performance and customer requirements must also be considered when making the decision whether or not to clean. As the electronics industry packages more and more functionality on less and less real estate, soldering yields need to increase in order for the assembly process to remain profitable. This requires not only attention to the product's design for manufacturing but it may also require aggressive fluxes to be used in the assembly process. When aggressive fluxes are employed, the necessity for cleaning is greatly increased. The particular combination of flux and cleaning option depends on product design, process capabilities, end point requirements, and environmental considerations. Pending restrictions on the production and use of chlorofluorocarbons (CFCs), and the potential for tighter controls on chlorinated solvents and aqueous detergent effluents, are certain to add to the cost of standard processes. For these reasons alternative cleaning processes have been explored. The evaluation and subsequent use of water soluble flux with ‘water only’ cleaning, terpene cleaning of rosin flux residues, low solids flux ‘no‐clean’ wave soldering and ‘no‐clean’ assembly using reflowed rosin based solder pastes within AT&T are reviewed. A user's assessment of aqueous and semi‐aqueous cleaning is presented which indicates that there are acceptable alternatives to CFCs.

Details

Circuit World, vol. 16 no. 3
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 June 2008

G Wenger

As a retired academic, I have written many academic papers over the years. This is not an academic paper; it is a personal account of my experiences in autumn 2007 of six days in…

Abstract

As a retired academic, I have written many academic papers over the years. This is not an academic paper; it is a personal account of my experiences in autumn 2007 of six days in an NHS hospital in Wales. My previous experience of hospitals in the UK consisted of having my tonsils out in 1947 and visiting my husband and parents who were patients in the same hospital over the course of the last years of their lives and of visiting friends in hospitals.

Details

Quality in Ageing and Older Adults, vol. 9 no. 2
Type: Research Article
ISSN: 1471-7794

Keywords

Article
Publication date: 13 August 2018

Meri Duryan and Hedley Smyth

The purpose of this paper is to address hierarchies in a large program of projects. It explores cultivation of communities of practice (CoP) within a hierarchical client…

1064

Abstract

Purpose

The purpose of this paper is to address hierarchies in a large program of projects. It explores cultivation of communities of practice (CoP) within a hierarchical client organization that manages multi-billion-euro infrastructure programs and projects.

Design/methodology/approach

This paper is based on an exploratory longitudinal case study approach involving action research. In-depth semi-structured interviews, company records, industry reports and observation from a case study in the hierarchical bureaucracy were translated into the language of cognitive maps for software analysis and subsequent interpretation.

Findings

The findings highlight the importance of hierarchy constraints and program management practices in project-based firms. The involvement of senior management in CoP cultivation reinforced the community’s contribution to strategic value creation in the firm under scrutiny.

Research limitations/implications

This paper mobilizes the concepts of boundary spanning and loose coupling as a way of analyzing the role of CoPs in bureaucratic hierarchies to promote learning and knowledge transfer. The results of the study suggest that application of those concepts can contribute to sustainability of CoPs in hierarchical organizations by giving them social space to span horizontal and vertical boundaries.

Practical implications

The authors practically contribute to the field by demonstrating the process and the impact of CoP sponsors’ engagement in their cultivation. This was enabled through the research-oriented action research component. The paper also concludes that cognitive mapping may provide a useful addition to engaged research, potentially simulating and influencing change in practice.

Originality/value

The academic contribution concerns understanding the roles of hierarchies, program management and CoP cultivation in project-based firms. It offers clear guidelines for managers of hierarchical bureaucracies to cultivate CoPs to address hierarchical constraints and how CoPs differ in organizational form.

Details

International Journal of Managing Projects in Business, vol. 12 no. 2
Type: Research Article
ISSN: 1753-8378

Keywords

Open Access
Article
Publication date: 5 July 2021

Adele Berndt

Sport is an important economic activity, and understanding the role of teams and managers is necessary, yet managers – specifically their brand personas – have been the subject of…

3574

Abstract

Purpose

Sport is an important economic activity, and understanding the role of teams and managers is necessary, yet managers – specifically their brand personas – have been the subject of limited research. The purpose of this research is to explore the brand persona of a football manager, using Arsène Wenger as a case.

Design/methodology/approach

Due to the exploratory nature of the study, qualitative methods were used to explore the brand-building activity. Media reports and images that centred on Arsène Wenger's words covering a three-year period were analysed. In total, 1364 articles and 23 images were analysed in NVivo, using both a priori and emergent codes.

Findings

The findings show the construction of the brand persona in three main dimensions pertinent to his role as a manager. The first is the performance in the managerial role in which Arsène Wenger is appointed, the second is associated with the person (including emotions and self-expression) and the third is the context (i.e. football) in which the manager operates.

Research limitations/implications

The research focused on one manager while he was managing a premier league club and is limited to England.

Practical implications

While proposing a theoretical model, this study proposes football clubs understand a manager's persona in relation to the club's brand and the interactive effect. The support of the club on the persona is also indicated.

Originality/value

Football managers have received some research attention, but there has been no analysis of their brand personas. This study expands the understanding of the contribution of the manager to the club brand.

Details

International Journal of Sports Marketing and Sponsorship, vol. 23 no. 1
Type: Research Article
ISSN: 1464-6668

Keywords

Article
Publication date: 1 May 2003

Thomas E. Drabek and David A. McEntire

Research on emergent behavior has been a significant topic within disaster studies. Through a detailed review of the literature we provide background information about this…

9002

Abstract

Research on emergent behavior has been a significant topic within disaster studies. Through a detailed review of the literature we provide background information about this particular branch of disaster sociology. Following a brief discussion of the process by which literature was selected, important trends and areas of debate are discussed. These include the validation of previous findings, an expansion of the discussion on emergent phenomena and a critique of the bureaucratic approach. We conclude with implications for the theory and practice of emergency management.

Details

Disaster Prevention and Management: An International Journal, vol. 12 no. 2
Type: Research Article
ISSN: 0965-3562

Keywords

Article
Publication date: 27 May 2014

Nicholas Theodorakopoulos, Carmel McGowan, David Bennett, Nada Kakabadse and Catarina Figueira

The purpose of this paper is to demonstrate analytically how entrepreneurial action as learning relating to diversifying into technical clothing – i.e. a high-value manufacturing…

Abstract

Purpose

The purpose of this paper is to demonstrate analytically how entrepreneurial action as learning relating to diversifying into technical clothing – i.e. a high-value manufacturing sector – can take place. This is particularly relevant to recent discussion and debate in academic and policy-making circles concerning the survival of the clothing manufacture industry in developed industrialised countries.

Design/methodology/approach

Using situated learning theory (SLT) as the major analytical lens, this case study examines an episode of entrepreneurial action relating to diversification into a high-value manufacturing sector. It is considered on instrumentality grounds, revealing wider tendencies in the management of knowledge and capabilities requisite for effective entrepreneurial action of this kind.

Findings

Boundary events, brokers, boundary objects, membership structures and inclusive participation that addresses power asymmetries are found to be crucial organisational design elements, enabling the development of inter- and intracommunal capacities. These together constitute a dynamic learning capability, which underpins entrepreneurial action, such as diversification into high-value manufacturing sectors.

Originality/value

Through a refinement of SLT in the context of entrepreneurial action, the paper contributes to an advancement of a substantive theory of managing technological knowledge and capabilities for effective diversification into high-value manufacturing sectors.

Details

Journal of Manufacturing Technology Management, vol. 25 no. 5
Type: Research Article
ISSN: 1741-038X

Keywords

1 – 10 of over 3000