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1 – 10 of 165R.D. Rust, D.A. Doane and I. Sawchyn
The bonding of surface mounted components to printed wiring boards (PWBs) is critical to the high yield assembly of components to the PWB. This process is one of the last steps…
Abstract
The bonding of surface mounted components to printed wiring boards (PWBs) is critical to the high yield assembly of components to the PWB. This process is one of the last steps performed in a complicated manufacturing and assembly sequence. Poor bondability at this late stage of assembly produces costly scrap. Aggressive wet‐chemical processes may succeed in cleaning the residues from the metal bonding lands, but in the process the polymeric materials that surround the land areas may be mechanically or visually damaged. Even when processing is carefully controlled during the final formation of land areas in the conformal coating, a thin residue, often invisible to the eye, can partially or fully cover the bonding land area. The residue may be extremely thin, but it inhibits bonding and is very resistant to conventional wet‐chemical cleaning methods. Plasma chemical etching is the one chemical process which can remove the residue from the metal lands and restore bondability without damaging other surfaces of the ready‐to‐assemble PWB. This paper reports examples of plasma removed residues from PWB surface mount bonding lands. The land areas are defined in photodefinable conformal coatings by conventional photolithographic techniques and have a non‐visible surface residue which inhibits the subsequent plating or soldering of the copper land. Auger analyses of the copper land surfaces prior to plasma processing show significant carbon peaks indicative of a polymeric residue. Auger analyses of the copper land surfaces following plasma processing show that the strong carbon peaks are gone.
J. Lau, T. Krulevitch, W. Schar, M. Heydinger, S. Erasmus and J. Gleason
The mechanical and thermal responses of encapsulated flip chip solder bumps on a surface laminar circuit (SLC) board have been determined in this study. The mechanical responses…
Abstract
The mechanical and thermal responses of encapsulated flip chip solder bumps on a surface laminar circuit (SLC) board have been determined in this study. The mechanical responses of the solder bumps and encapsulant have been obtained by shear, tension and torsion tests. The thermal stress and strain in the solder bumps and encapsulant have been determined by a non‐linear finite element method and the thermal fatigue life of the corner solder bump is then estimated based on the calculated plastic strains, Coffin‐Manson law and isothermal fatigue data of solders. Also, an assembly process of the test boards is presented.
Wojciech Stęplewski, Andrzej Dziedzic, Kamil Janeczek, Aneta Araźna, Krzysztof Lipiec, Janusz Borecki and Tomasz Serzysko
The purpose of this paper is to investigate the behavior of embedded passives under changing temperature conditions. Influence of different temperature changes on the basic…
Abstract
Purpose
The purpose of this paper is to investigate the behavior of embedded passives under changing temperature conditions. Influence of different temperature changes on the basic properties of embedded passives was analyzed. The main reason for these investigations was to determine functionality of passives for space application.
Design/methodology/approach
The investigations were based on the thin-film resistors made of Ni-P alloy, thick-film resistors made of carbon or carbon-silver inks, embedded capacitors made of FaradFlex materials and embedded inductor made in various configurations. Prepared samples were examined under the influence of a constant elevated temperature (100, 130 or 160°C) in a long period of time (minimum of 30 h), thermal cycles (from −40 to +85°C) or thermal shocks (from −40 to +105°C or from −40 to +125°C).
Findings
The achieved results revealed that resistance drift became bigger when the samples were treated at a higher constant temperature. At the same time, no significant difference in change in electrical properties for 50 and 100 Ω resistors was noticed. For all the tests, resistance change was below 2 per cent regardless of a value of the tested resistors. Conducted thermal shock studies indicate that thin-film resistors, coils and some thick-film resistors are characterized by minor variations in basic parameters. Some of the inks may show considerable resistance variations with temperature changes. Significant changes were also exhibited by embedded capacitors.
Originality/value
The knowledge about the behavior of the operating parameters of embedded components considering environmental conditions allow for development of more complex systems with integrated printed circuit boards.
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The driving forces behind recent significant improvements in organic packages for microelectronic applications are electrical performance, product weight, size and manufacturing…
Abstract
The driving forces behind recent significant improvements in organic packages for microelectronic applications are electrical performance, product weight, size and manufacturing cost. A very careful selection of optimum manufacturing processes, equipment and materials, and stringent control of critical manufacturing operations are prerequisites for success in this emerging market place. Major technical and business related challenges to a printed circuit board manufacturer who plans to enter this market are discussed.
– This study aims to examine the economic factors that determine innovation pattern in centralized and decentralized economies and organizations.
Abstract
Purpose
This study aims to examine the economic factors that determine innovation pattern in centralized and decentralized economies and organizations.
Design/methodology/approach
Empirical evidence on innovation in the centralized economy of the Soviet Union is reviewed. Existing theoretical literature in this area relies on the incentives of decision-makers in centralized organizations and on the concept of soft budget constraint in centralized command economies and hard budget constraint in market economies. This study advocates applying the hierarchy/polyarchy model of innovation screening to explain the pattern of innovation in centralized economic systems.
Findings
Screening and development of innovation projects can be organized in a centralized or decentralized fashion. The differences in innovation between centralized and decentralized economic systems may be explained by elements of the principal-agent theory, the soft budget constraint model, and the theory of decision-making in hierarchies and polyarchies. Empirical evidence shows a sharp slowdown in both innovation and economic growth in the Soviet economy following the economic decision-making reform of 1965. The theoretical explanation most consistent with this evidence is the hierarchy decision-making model.
Originality/value
Comparisons of innovation in centralized and decentralized economies traditionally relied on decision-makers' incentives and the concept of soft budget constraint. Upon analysis of empirical evidence from the centralized Soviet economy, this study advocates explaining innovation patterns based on decision-making theory of hierarchy.
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The purpose of this paper is to examine how shadow constituents are redefining corporate social responsibility (CSR) through activism, and how oil companies in Nigeria are…
Abstract
Purpose
The purpose of this paper is to examine how shadow constituents are redefining corporate social responsibility (CSR) through activism, and how oil companies in Nigeria are responding to this development.
Design/methodology/approach
This paper contributes to the conceptual framework of CSR which asserts that whereas all stakeholders of a company do not have an equal say in its strategic direction, they are affected by such direction, and must hence be considered.
Findings
The findings reveal these points: activists are gaining a strong foothold in forcing oil companies to cooperate with their vision of social change; Nigeria lacks legislation compelling oil companies to contribute to the development of their host communities; and although internal oil company documents suggest efforts to help their hosts communities have been made, no meaningful agreement between the oil companies and the indigenous communities have been reached.
Research limitations/implications
The paper encourages a broader conception of CSR. Shadow constituents have become such influence wielding stakeholders in organizations today that we need to explore more fully the role they play in dictating public agenda and influencing policy globally.
Practical implications
Multinational corporations can develop a better understanding of strategies and techniques that can enable them to balance the interests of a wider group of stakeholders and manage the interconnected social, environmental and economic impacts of their businesses.
Originality/value
This paper enriches the research database on CSR.
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Joshua Doane, Judy A. Lane and Michael J. Pisani
Volume 25 celebrates the 25th year of publication for the American Journal of Business (AJB). Launched by eight MAC schools of business in March 1986, the Journal has featured…
Abstract
Volume 25 celebrates the 25th year of publication for the American Journal of Business (AJB). Launched by eight MAC schools of business in March 1986, the Journal has featured more than 700 authors who have contributed more than 330 research articles at the intersection of theory and practice. From accounting to marketing, management to finance, the Journal prominently covers the breadth of the business disciplines as a general business outlet intended for both practitioners and academics. As the Journal reaches out beyond the MAC in sponsorship, authorship, and readership, we assess the Journal’s first quarter century of impact.
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Michael Vitacco, Alynda Randolph, Kaitlyn Soroko, Janina Velez and Diandra Sigurdsson
Response style evaluation is a fundamental component of forensic examinations. This retrospective study aims to evaluate how measures of feigning performed with individuals with…
Abstract
Purpose
Response style evaluation is a fundamental component of forensic examinations. This retrospective study aims to evaluate how measures of feigning performed with individuals with intellectual disabilities (ID) who were undergoing competency to proceed to trial evaluations.
Design/methodology/approach
Using a known-groups design (ID vs non-ID) with 145 individuals, 37 individuals met diagnostic criteria for ID. The individuals were administered the Miller Forensic Assessment of Symptoms Test (M-FAST; Miller, 2001), the Inventory Legal Knowledge (ILK; Musick and Otto, 2010), the Evaluation Competency to Stand Trial-Revised, atypical presentation scale (ATP; Rogers et al., 2004b) and the Competence Assessment for Standing Trial-Mental Retardation (Everington and Luckasson, 1992).
Findings
The total ILK demonstrated differences between groups with a large effect size (Cohen’s d = 1.02). Six items on the ILK had over a 30% difference as a function of group. However, two revised scales from the ILK, the R-ILK-90 and the R-ILK-95 (Rogers et al., 2017), did not demonstrate differences as a function of group membership with small effect sizes (Cohen’s ds = 0.02 and 0.29). The M-FAST total score and ATP scales were not different between groups, although results demonstrated that individuals with ID would be potentially more at risk to for misclassification as feigning on the M-FAST.
Research limitations/implications
This study has several limitations. It is a retrospective study with a relatively small sample size so additional research is needed to substantiate the results. However, this study highlights the potential for individuals with intellectual disabilities to be disadvantaged when undergoing competency to stand trial evaluations.
Practical implications
This manuscript shows that individuals with ID are at-risk for being mislabeled as feigning when employing standard measures of response style testing if appropriate cautions are not used. However, revised measures that take into account baseline information of legal knowledge offer a way forward that may prevent false positives with individuals with ID.
Social implications
The mislabeling of individuals with ID could lead to significant problems, including harsh sentences and unnecessary incarcerations. This manuscript provides real-world data and encourages clinicians to be mindful when evaluation individuals with ID for court-ordered evaluations.
Originality/value
This manuscript is critical, as it shows that caution is needed when using instruments of feigning with individuals with ID who are undergoing competency evaluations. This has value for clinicians who are tasked with completing these evaluations for the courts.
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Martha E. Williams, Ellen Sutton and Brett Sutton
This is the second in a continuing series of articles summarizing and commenting on new database products and the first one covering the topics of social sciences, humanities…
Abstract
This is the second in a continuing series of articles summarizing and commenting on new database products and the first one covering the topics of social sciences, humanities, general, multidisciplinary and news. Companion articles covering science, technology and medicine (which appeared in the previous issue of Online & CDROM Review) and covering business and law (to appear in the next issue) complement this article. The articles are based on the newly‐appearing database products in the Gale Directory of Databases (GDD). This was created by merging Computer‐Readable Databases: A Directory and Data Sourcebook (CRD) together with the Directory of Online Databases (DOD) and the Directory of Portable Databases (DPD). The first of GDD was published in January 1993.
Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Tenn. 37203. Mrs. Cheney does not sell the books listed here. They are…
Abstract
Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Tenn. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.