Alternatives to conventional oxides were introduced in the mid‐1990s as part of innerlayer bonding processes that were significantly less expensive than reduced oxides. This was…
Abstract
Alternatives to conventional oxides were introduced in the mid‐1990s as part of innerlayer bonding processes that were significantly less expensive than reduced oxides. This was due to their lower equipment costs, shorter cycle times, and lower chemistry costs. However, the first offerings of these processes forced printed circuit board suppliers to accept some performance compromises in the areas of waste treatment, filtration costs, process control, and peel strength.As chemical suppliers further refined their alternative oxide process chemistries, many of these deficiencies were overcome and a second generation was introduced. The second generation improvements have addressed the earlier deficiencies and present the so called “alternative oxides” as a cost effective, reliable process for innerlayer bonding.
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John Gebhardt, Keith Waryold, Dave Oglesby and John Graves
The demand for higher operating speeds and increasing densification in electronic packages is driving designers to reduce feature sizes in order to accommodate increases in I/O…
Abstract
The demand for higher operating speeds and increasing densification in electronic packages is driving designers to reduce feature sizes in order to accommodate increases in I/O counts. Consequently, printed circuit board manufacturers are turning to new manufacturing techniques and new materials in order to meet these demands from their customers. Sequential build‐up is one such technique and a plethora of new materials is available to support these innovative routes to high‐density interconnect circuitry. The basic concept involves the addition of extra layers of dielectric and copper on to a multi‐layered board. The additional circuitry is then connected to the underlying board using suitably formed microvias. Focuses on the metallization of microvias using a straight‐through horizontal metallization process. Particular emphasis is placed on the importance of equipment design, the chemistry of the solutions used and optimization of fluid exchange to ensure good coverage of these small features.
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Alexandra L. Ferrentino, Meghan L. Maliga, Richard A. Bernardi and Susan M. Bosco
This research provides accounting-ethics authors and administrators with a benchmark for accounting-ethics research. While Bernardi and Bean (2010) considered publications in…
Abstract
This research provides accounting-ethics authors and administrators with a benchmark for accounting-ethics research. While Bernardi and Bean (2010) considered publications in business-ethics and accounting’s top-40 journals this study considers research in eight accounting-ethics and public-interest journals, as well as, 34 business-ethics journals. We analyzed the contents of our 42 journals for the 25-year period between 1991 through 2015. This research documents the continued growth (Bernardi & Bean, 2007) of accounting-ethics research in both accounting-ethics and business-ethics journals. We provide data on the top-10 ethics authors in each doctoral year group, the top-50 ethics authors over the most recent 10, 20, and 25 years, and a distribution among ethics scholars for these periods. For the 25-year timeframe, our data indicate that only 665 (274) of the 5,125 accounting PhDs/DBAs (13.0% and 5.4% respectively) in Canada and the United States had authored or co-authored one (more than one) ethics article.
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Musab Jamal Maraqa, Rafael Sacks and Sabrina Spatari
The study aims to test, measure and quantify the impacts of lean construction and BIM implementation on flow in construction projects.
Abstract
Purpose
The study aims to test, measure and quantify the impacts of lean construction and BIM implementation on flow in construction projects.
Design/methodology/approach
Detailed control data from a set of 18 high-rise residential construction projects executed between years 2011 and 2020 were analyzed using the construction flow index (CFI), a measure of workflow quality. Seven comparable projects with a diverse range of LPS, BIM, VDC and 5S implementation were selected to compare the impacts of these innovations on flow.
Findings
Implementing BIM in the big room and applying the last planner system and other lean construction techniques increased the CFI from 4.31 to 8.12 (on a 10-point scale). Avoiding trades crossing one another's paths between tasks was the most significant aspect of improved flow. Moreover, the benefits of implementing lean practices with BIM or VDC were found to be measurably greater than when these approaches were implemented separately.
Research limitations/implications
The primary limitation of the study is that the degree of confidence in the results is limited by the nature of the case study approach. Although 18 is a respectable number of case study projects, it cannot offer the degree of confidence that a broader, representative sample of projects could. Similarly, the case studies are all drawn from the same construction context (residential apartments) and the same geographic region, which necessarily limits confidence concerning the degree to which the findings can be generalized.
Originality/value
The research is the first of its kind to quantitatively assess the impacts of BIM and lean construction on flow. Use of the CFI to quantify flow quality also highlights the potential value of CFI in providing project managers and planners a clear view of the smoothness or irregularity of flow and of differences between subcontractors' production rates.