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Flex‐rigid circuits have been used for many years, primarily by the military, as a method to reduce the size and increase the reliability of electronic systems. However, in today's emerging designs where high speed ASICs are often the dominant components, flex‐rigid circuit assemblies are now an attractive solution for providing high density transmission line interconnects from board to board. Much of today's circuitry is being committed to ASIC designs to increase both circuit density and speed. Following this path, designers are faced with the task of interconnecting high lead count SMT packages often with as many as 300 to 500 leads per device, each dissipating several watts. At these power densities conductive cooling through the circuit board is often a necessity, dictating the use of either metal cores or heat exchangers. To make efficient use of the core and minimise weight, designs generally require SMT packages to be mounted on both sides of the core with electrical communication from side to side. However, as more exotic core materials (carbon fibre matrix, beryllium, etc.) and liquid cooled heat exchangers are used, electrical communication through the core has become difficult, if not impossible, in some cases. Instead, high density flex‐rigid assemblies are used to partition the circuit, allowing the board to ‘fold’ over the core. This results in hundreds of signal lines that must cross the flex, obeying the electrical design rules dictated by the rigid sections to maintain impedance values and crosstalk margins. This paper focuses on recent work at AIT, producing high density flex‐rigid circuits using embedded discrete wiring technology to meet the above requirements. Using 0.0025 in. diameter polyimide insulated wire, as many as 100 lines per linear inch can pass over the flex region on a single layer. This generally results in a single flex layer where all wires can be referenced to a continuous ground plane from board to board. Controlled impedance is easily maintained due to the uniform wire geometry, and high frequency attenuation is significantly lower than on equivalent etch circuit designs due to the smooth surface finish on the wire. In addition, the high interconnection density offered by this technique reduces the overall thickness of the rigid sections, thereby minimising the thermal resistance to the core.

In future generations, electronic systems will rely extensively on advanced IC technology to achieve higher performance levels. However, with limits placed on the level of integration that can be obtained on a single IC, a need still exists for an interconnection hierarchy to provide the necessary density transform between system components. A recent addition to many high performance interconnection structures has been the Multichip Module. By eliminating the conventional IC package, MCMs have dramatically reduced the electrical length between devices, thereby minimising propagation delay, crosstalk, and attenuation. Although MCM techniques will offer many performance advantages, they also present many design challenges at subsequent levels of interconnection. This paper will focus on the requirements of MCM backplanes interconnecting several modules and, as a solution, will present recent work on advanced metal core substrates. MCM substrates provide a tremendous density advantage, however, the interconnection between modules is still a formidable task. Modules often have I/O densities of 300 to 500 leads per square inch and typically dissipate 10 to 50 watts per square inch. In addition, with sub‐nanosecond rise times, the distance between modules is often sufficient for signal paths to be treated as transmission lines. In an effort to meet these requirements, metal core circuits based on copper, copper Invar, and copper molybdenum have been fabricated using 0·0025 in. diameter embedded discrete wiring technology. Combined with a Kevlar surface layer suitable for wire bonding and blind laser drilled vias to access the internal wires, this technique offers many benefits. As many as 4 conductors can pass between holes on 0·050 in. centres in a single wiring layer only 0·018 in. thick. With the absence of interstitial vias, additional substrate area can be dedicated to create a sizeable thermal path, essential to conduct the heat from the MCM to an internal metal core. Together, these features have made this an attractive approach for interconnecting multichip modules.

In the never‐ending quest for speed, designers are now turning to digital GaAs integrated circuits both to extend the bandwidth of current designs and in some cases to generate a whole new class of products never before possible. The engineer well versed in high speed ECL design techniques generally understands the problems associated with this transfer to GaAs logic. However, even with the design task well defined, the exact solution for interconnecting devices is often difficult and stresses the capabilities of existing multilayer printed circuit techniques using conventional dielectric materials and processing. This paper examines the design task in detail, and will present recent developments in shielded discrete wiring techniques as a possible solution for GaAs packaging.

To use a behavioral measure of legitimacy to study how differences in negotiating style and status affect the legitimacy of persons in high-power network positions. Predictions include (1) that powerful network actors who negotiate using a pro-group style will maintain legitimacy better than will those who negotiate selfishly and (2) those higher in status will be granted more legitimacy both before and after exchange than powerful actors lower in status.

An experimental study in which participants were connected in networks to powerful partners who were portrayed as consistently high or low on several status characteristics. Both before and after exchange, participants evaluated partners on a number of dimensions and made decisions on whether to vote to join a coalition to take the partner's power away, a direct behavioral indicator of legitimacy.

High-power partners lost legitimacy over the course of exchange irrespective of whether they negotiated in pro-group or selfish ways, and irrespective of whether they were high or low in status. This effect was pronounced for partners who negotiated selfishly. Although partner status predicted legitimacy prior to exchange, legitimacy evaluations after exchange appeared entirely driven by the partner's negotiating style (how the power was used) and not by status.

The project introduces a new behavioral measure of legitimacy that correlated highly with self-report items and should be of value in future research. The study also indicates promising directions for future research that might disentangle effects of power and status on legitimacy, along with adjudicating among explanations for why this study did not find status effects on legitimacy.

Advanced discrete wiring systems are being developed to produce state‐of‐the‐art circuit boards for packaging the next generation electronic systems. The demands placed on electronic interconnection by very high speed VLSI devices have created a need for large circuit boards that will support high interconnection density. At the same time these circuit boards must maintain the necessary transmission line parameters to transport signals with sub‐nanosecond rise times and retain signal fidelity.

Purpose – Concerns about expenditure on legal aid in England and Wales have led to greater focus on ‘value for money’ and increased strategic targeting of resources. To inform targeting, the English and Welsh Civil and Social Justice Survey has been used to investigate the relative severity of different civil justice problem types. Thus, the survey has included a range of severity indices and related questions. However, this study takes a different approach in exploring how a seeming ‘defect’ of the survey, failure of autobiographical memory, may shed some of the clearest light on not just the issue of problem severity but also problem incidence.Methodology/approach – We examine failures of autobiographical memory of civil justice problems and ask what they can tell us about problem severity.Findings – We find that failures of autobiographical memory provide a useful guide to relative severity of civil justice problems of different types. They also provide a means to more accurately estimate the prevalence of problems.Originality/value of paper – This paper is the first to examine the relative severity and incidence of civil justice problems through an analysis of recall patterns.

Increasing speeds combined with the level of integration that can be obtained with advanced IC technology has dramatically changed the interconnection requirements for high performance electronic systems. With much of today's circuitry being implemented in custom silicon, IC technology has allowed both a dramatic reduction in size and a tremendous increase in performance. However, in terms of the interconnection problem, the by‐product of advanced IC technology is a new generation of IC s that often require several hundred I/OS, exhibit rise times of 150 ps to 300 ps, and dissipate several watts per device. As demanding requirements are placed upon circuit boards, the complexity of the design task increases dramatically, since a working solution must simultaneously address interconnection density, signal integrity and thermal performance. This paper examines embedded discrete wiring technology as a high density solution that meets the requirements necessary for transporting high speed digital signals.

School superintendents are in search of development opportunities that can help them enhance their leadership capacity in order to respond to new demands and changes in the environment. This paper focuses on the professional development behaviors of school superintendents identified through a comparative study of two groups. One group participated in a Diagnostic Executive Competency Assessment System (DECAS) and the second group did not have any assessment experience. Findings suggest that both groups of school superintendents tend to engage in development experiences and activities. While there are some differences in the development behaviors of these two groups, it is interesting that all school superintendents recognize improvement (of self, schools, and student achievement) as a motivation to enhance their capacity in several ways.

This paper presents stress inoculation as a method for reducing executives’ stress and enhancing their resilience and performance.

A review of theory and research on executive stress, resilience, and stress inoculation training was conducted.

Across studies, stress inoculation training has yielded reductions in performance anxiety and state anxiety while improving performance under stress.

Stress inoculation training offers a highly customized and practical way for executives to design adaptive responses to the stressors they find particularly difficult.

Stress inoculation training traditionally has been applied in clinical settings and in extremely stressful settings (e.g., military, law enforcement). This article describes how this intervention may be applied within organizations as a needed addition to the complement of stress management approaches currently offered to executives.