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Article
Publication date: 1 February 1982

G. Leonida

Mass soldering has not entirely replaced manual soldering and it is possible to enumerate various applications of the latter. The basic tool for the manual process is the…

Abstract

Mass soldering has not entirely replaced manual soldering and it is possible to enumerate various applications of the latter. The basic tool for the manual process is the soldering iron, with its vital major component, the bit. Parameters to be taken into account include power available at the bit, maximum bit temperature, thermal capacity and recovery time. Considerable detail is provided on the criteria that govern the choice of soldering iron bits, and a few useful soldering aids described. Although individual styles of hand soldering emerge, following the preferred practice should guarantee reliable joints. After an outline of the optimal operating procedure, some information is given on touch‐up, desoldering and structural joints. This article is an extract from the book “Handbook of Printed Circuit Design, Manufacture, Components and Assembly” by G. Leonida, published by Electrochemical Publications Limited, 8 Barns Street, Ayr, Scotland.

Details

Circuit World, vol. 8 no. 3
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 June 1997

W. MacLeod Ross and G. Leonida*

This issue of the journal features the third part of a three‐part series whichcomprises Chapter 8 from Volume 1 of the recently published book ‘AComprehensive Guide to the…

127

Abstract

This issue of the journal features the third part of a three‐part series which comprises Chapter 8 from Volume 1 of the recently published book ‘A Comprehensive Guide to the Manufacture of Printed Board Assemblies’ edited by W. MacLeod Ross. Volume 1, containing 800 pages, and Volume 2, scheduled to be published in the Spring of 1997 and estimated to contain around 900 pages, will, as far as the publishers are aware, be the most comprehensive book ever published on the subject of printed boards and printed board assemblies.

Details

Circuit World, vol. 23 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 March 1997

W. MacLeod Ross and G. Leonida

This issue of the journalfeatures the second part of a three part series which comprises Chapter 8 from Volume 1 of therecently published book ‘A Comprehensive Guide to the

446

Abstract

This issue of the journal features the second part of a three part series which comprises Chapter 8 from Volume 1 of the recently published book ‘A Comprehensive Guide to the Manufacture of Printed Board Assemblies’** edited by W. MacLeod Ross.Volume 1, containing 800 pages, and Volume 2, scheduled to be published in the Spring of 1997 and estimated to contain around 900 pages, will, as far as the publishers are aware, be the most comprehensive book ever published on the subject of printed board assemblies.

Details

Circuit World, vol. 23 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 9 March 2012

Pietro Evangelista, Riccardo Mogre, Alessandro Perego, Antonino Raspagliesi and Edward Sweeney

In today's competitive scenario, effective supply chain management is increasingly dependent on third‐party logistics (3PL) companies' capabilities and performance. The…

3106

Abstract

Purpose

In today's competitive scenario, effective supply chain management is increasingly dependent on third‐party logistics (3PL) companies' capabilities and performance. The dissemination of information technology (IT) has contributed to change the supply chain role of 3PL companies and IT is considered an important element influencing the performance of modern logistics companies. Therefore, the purpose of this paper is to explore the relationship between IT and 3PLs' performance, assuming that logistics capabilities play a mediating role in this relationship.

Design/methodology/approach

Empirical evidence based on a questionnaire survey conducted on a sample of logistics service companies operating in the Italian market was used to test a conceptual resource‐based view (RBV) framework linking IT adoption, logistics capabilities and firm performance. Factor analysis and ordinary least square (OLS) regression analysis have been used to test hypotheses. The focus of the paper is multidisciplinary in nature; management of information systems, strategy, logistics and supply chain management approaches have been combined in the analysis.

Findings

The results indicate strong relationships among data gathering technologies, transactional capabilities and firm performance, in terms of both efficiency and effectiveness. Moreover, a positive correlation between enterprise information technologies and 3PL financial performance has been found.

Originality/value

The paper successfully uses the concept of logistics capabilities as mediating factor between IT adoption and firm performance. Objective measures have been proposed for IT adoption and logistics capabilities. Direct and indirect relationships among variables have been successfully tested.

Article
Publication date: 23 June 2014

Andrey Korotayev and Julia Zinkina

A substantial number of researchers have investigated the global economic dynamics of this time to disprove unconditional convergence and refute its very idea, stating the…

Abstract

Purpose

A substantial number of researchers have investigated the global economic dynamics of this time to disprove unconditional convergence and refute its very idea, stating the phenomenon of conditional convergence instead. However, most respective papers limit their investigation period with the early or mid-2000s. In the authors’ opinion, some of the global trends which revealed themselves particularly clearly in the second half of the 2000s call for a revision of the convergence issue. The paper aims to discuss these issues.

Design/methodology/approach

Several methodologies for measuring the global convergence/divergence trends exist in the economic literature. This paper seeks to contribute to the existing literature on unconditional β-convergence of the per capita incomes at the global level.

Findings

In the recent years, the gap between high-income and middle-income countries is decreasing especially rapidly. The gap between high-income and low-income countries, meanwhile, is decreasing at a much slower pace. At the same time, the gap between middle-income and low-income countries is actually widening. Indeed, in the early 1980s GDP per capita in the low-income countries was on average three times lower than in the middle-income countries, and this gap was totally overshadowed by the more than ten-time abyss between the middle-income and the high-income countries. Now, however, the GDP per capita in low-income countries lags behind the middle-income ones by more than five times, which is largely the same as the gap (rapidly contracting in the recent years) between the high-income and the middle-income countries. This clearly suggests that the configuration of the world system has experienced a very significant transformation in the recent 30 years.

Research limitations/implications

The research concentrates upon the dynamics of the gap in per capita income between the high-income, the middle-income, and the low-income countries.

Originality/value

This paper's originality/value lies in drawing attention to the specific changes in the structure of global convergence/divergence patterns and their implications for the low-income countries.

Article
Publication date: 1 March 1994

C.Y. Chan, A.H. Redford and N.N. Ekere

Rework is an integral part of printed circuit board assembly (PCBA) manufacturing. However, the state‐of‐the‐art for PCBA rework still relies on operator activity and is therefore…

Abstract

Rework is an integral part of printed circuit board assembly (PCBA) manufacturing. However, the state‐of‐the‐art for PCBA rework still relies on operator activity and is therefore semi‐automatic. As a result, the quality of rework depends very much on the skill of the operator. When developing an automatic PCBA rework cell, the cell controller is an essential part which organises and controls the overall rework operation. This paper describes the software modelling of the cell controller for the PCBA rework cell which has been implemented for reworking through‐hole and surface mounted components. The software model is based on hybrid representations and rule‐based control.

Details

Soldering & Surface Mount Technology, vol. 6 no. 3
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 April 1981

On wave soldered boards, the simultaneous appearance of more than one defect, attributable to the same cause, is relatively common. This may help in diagnosing the cause.

Abstract

On wave soldered boards, the simultaneous appearance of more than one defect, attributable to the same cause, is relatively common. This may help in diagnosing the cause.

Details

Circuit World, vol. 8 no. 1
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 January 1992

H. Nakahara

Driven by the demand for higher density in electronic packaging, each signal plane of printed wiring board must accommodate more conductors. As a result, conductor width is…

Abstract

Driven by the demand for higher density in electronic packaging, each signal plane of printed wiring board must accommodate more conductors. As a result, conductor width is becoming narrower each year. This chapter reviews some of the important steps of forming finer line conductors in printed wiring boards, such as surface preparation, plating/etching, photo‐exposure, automatic optical inspection, etc.

Details

Circuit World, vol. 18 no. 2
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 January 1995

T. Yamada, R. Doyle and J. Barrett

The reduction in IC package lead pitches in surface mount solder assembly and the current high emphasis on quality and reliability of printed circuit assemblies have created a…

Abstract

The reduction in IC package lead pitches in surface mount solder assembly and the current high emphasis on quality and reliability of printed circuit assemblies have created a requirement for microanalysis of fine pitch solder joints in manufacturing situations. Of particular interest are metallographic analysis, detection of solder joint defects and mechanical strength testing of solder joints. Much has been published in the literature on the results of such evaluations in specific applications but little has been available on procedures for use in the microanalysis itself, particularly for fine pitch solder joints. Detailed procedures for fine pitch solder joint microanalysis, which the authors have verified down to 0.5 mm (0.02 in.) lead pitches, are presented. In particular, the authors present procedures for metallographic examination of tin‐lead and tin‐lead‐silver solder joints. In addition, test parameters are given for a repeatable technique of fine pitch solder joint mechanical strength testing that allows mechanical strength measurements to be obtained from almost every lead on a fine pitch surface mount IC package.

Details

Soldering & Surface Mount Technology, vol. 7 no. 1
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 February 1989

E. Goold

The potentially highly automated process of surface mounting electronic components directly onto a substrate or printed circuit board possesses a very weak link. Component…

Abstract

The potentially highly automated process of surface mounting electronic components directly onto a substrate or printed circuit board possesses a very weak link. Component movement subsequent to placement and before or during solder reflow leads to defect conditions such as tombstoning or rotational misalignment. This work investigates the feasibility of replacing this ‘weak’ assembly step(s) with ultrasonics. The selection and modification of suitable ultrasonic equipment is described as in the bonding of chip components onto PCBs. Reliability analysis of the resultant bonds along with bond quality in terms of shear strength and appearance under scanning electron microscope and optical microscope is studied. The results show that, with certain preferred directions of ultrasonic weld, weld preload and weld time bond strengths obtained compare very favourably with those achieved with the present surface mount technology reflow process, hence establishing the feasibility of ultrasonics for this application.

Details

Circuit World, vol. 15 no. 3
Type: Research Article
ISSN: 0305-6120

1 – 10 of 73