Keryn Lian, Manes Eliacin, Robert Lempkowski, Marc Chason, Matthew O'Keefe and James Drewniak
The purpose of this paper is to present a new class of printed circuit board (PCB)‐based, radio frequency micro‐electro‐mechanical systems (RF‐MEMS) switches and to describe the…
Abstract
Purpose
The purpose of this paper is to present a new class of printed circuit board (PCB)‐based, radio frequency micro‐electro‐mechanical systems (RF‐MEMS) switches and to describe the packaging method and evaluate performance.
Design/methodology/approach
Traditional PCB materials and processes were combined with photolithographic high‐density interconnect (HDI) and MEMS to form 3D high‐performance RF switches.
Findings
A new type of MEMS RF switch has been developed on a PCB platform. Using processes analogous to those used for silicon MEMS, PCB, and HDI technologies were utilized to fabricate these 3D structures. The PCB‐based microstructures are “mil‐scale” rather than the “micro‐scale” of silicon MEMs. A co‐fabrication packaging method for the MEMS RF switch was also developed. The PCB‐based MEMS switches have demonstrated excellent RF performance and “hot‐switching” RF power‐handling capability. PCB‐based MEMS RF switches have the advantages of low cost and amenability to scale‐up for a high degree of integration.
Research limitations/implications
Further development on photo imageable dielectric materials will enable this technology to improve yield and processability.
Originality/value
The paper describes the development of PCB‐based MEMS RF switches. These elements will enable new applications and enhance the functionality of PCBs. They are also more amenable to system integration compared with silicon MEMS.
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Keryn Lian, Shawn O'Rourke, Daniel Sadler, Claudia Gamboa, Robert Terbrueggen and Marc Chason
The purpose of this paper is to present the development of printed wiring board (PWB)‐based microfluidic building blocks and their integration into systems for DNA amplification…
Abstract
Purpose
The purpose of this paper is to present the development of printed wiring board (PWB)‐based microfluidic building blocks and their integration into systems for DNA amplification and electronic detection.
Design/methodology/approach
Technologies from embedded passives (EP) and photolithographic high‐density interconnect are integrated into a traditional PWB platform to enable multifunctional electrochemical sensors for on‐chip detection of biological assays.
Findings
PWB materials and processes can be applied to develop microelectromechanical systems (MEMS) and microfluidic systems. On‐chip heaters using EP have been demonstrated with excellent accuracy. The on‐chip heaters can be used for localized temperature control as well as heat air pumps. The integration of EP and microchannels is a promising approach to add functionalities to the PWB‐based microsystems.
Research limitations/implications
Further integration of microchannels with the embedded heaters and electrochemical sensors will increase the compactness, functionality, and value of the PWB‐based microfluidic systems.
Originality/value
The paper describes the development and integration of PWB‐based building‐blocks such as EP and microchannels for MEMS and microfluidic applications. These elements will enable new applications and enhanced functionalities of PWB.
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Keryn Chalmers, David Hay and Hichem Khlif
In 2001, the US moved to regulate internal control reporting by management and auditors. While some jurisdictions have followed the lead of the US, many others have not. An…
Abstract
In 2001, the US moved to regulate internal control reporting by management and auditors. While some jurisdictions have followed the lead of the US, many others have not. An important question, therefore, is the relevance of internal control to stakeholders. The more specific issue of the benefits of US-style regulation of internal control reporting is also topical. We review studies on the determinants of internal control quality and its economic consequences for stakeholders including investors, creditors, managers, auditors and financial analysts. We extend previous reviews by focusing on US studies published since 2013 as well as all non-US studies investigating IC quality including countries regulating IC disclosure as well as unregulated settings and both developed and developing economies. In doing so, we identify research questions where evidence remains mixed and new directions in which there are research opportunities.
Three main insights arise from our analysis. First, evidence on the economic consequences of internal control quality suggests that the quality of internal control can have a significant effect on decision making by users of financial information. Second, the results of research on the empirical association between ownership structure, certain board characteristics and internal control quality is generally mixed. Empirical evidence concerning the association between audit committee characteristics and internal control quality generally supports a positive and significant association. Finally, while studies in non-US jurisdictions are increasing, opportunities remain to explore the determinants and consequences of internal control in other jurisdictions. Our review provides evidence for policy makers of whether there are benefits from requiring management and auditors to report on internal control over financial reporting.
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This paper aims to conduct a meta-analysis regarding the association between political connections and the cost of debt and tests for the moderating effect of the level of…
Abstract
Purpose
This paper aims to conduct a meta-analysis regarding the association between political connections and the cost of debt and tests for the moderating effect of the level of creditor protection on this relationship.
Design/methodology/approach
Keywords used to collect relevant empirical papers include “political connections, political ties, and political connectedness” from the one side, and “cost of loan finance, and cost of debt” from the other side. The search yields 24 published empirical papers from 2005 to 2022.
Findings
Findings show that there is a significant negative association between political connections and the cost of debt; this relationship is more pronounced only for countries characterized by a strong level of creditor protection. This moderating effect is further confirmed using meta-regression.
Originality/value
Findings are relevant for policymakers and managers in settings where relationship-based capitalism represents a prevailing feature as they highlight the important legal and institutional characteristics when considering the impact of political connections on the cost of debt. The paper also discusses some limitations inherent to this stream of research and proposes future research perspectives.