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In this chapter, we provide a brief historical framework of the events and policy changes that impacted the prosecution of terrorism over the past 50 years with emphasis placed on the changes that resulted from the 9/11 attacks.

We provide a review of relevant literature and complete the chapter by providing new data (2015) on case outcomes derived from the American Terrorism Study, a database housed in the Terrorism Research Center in Fulbright College, at the University of Arkansas.

Investigative and prosecutorial authority in U.S. terrorism cases has experienced ebbs and flows that correspond with terrorism attacks as well as missteps by the FBI, and each has impacted the success of prosecution efforts. Despite dramatic changes, the number of cases prosecuted after 9/11 is unprecedented, and conviction rates continue to climb.

This chapter provides the reader with a synopsis of the policy changes that have occurred in federal terrorism investigations and trials from the late 1960s upto the present. Based on that context, we provide an explanation of how those policy changes have impacted terrorism prosecutions.

The purpose of this paper is to investigate magneto-mechanical coupling occurring in magnetic resonance imaging (MRI) systems. The authors study influence of the strength of the background field on the coupling of mechanically isolated, conductive cylindrical structures and the so-called shields. This coupling has a strong impact on frequency-dependent thermal losses occurring in the shield structures which are of high importance in MRI systems.

In the investigations, numerical methods are applied. First, finite element methods taking into account the full magneto-mechanical coupling are used to investigate the coupled physical phenomena. As these calculations may be time-consuming, several approximate predictive methods are derived. Modal expansion factors and participation factors are based on combinations of structural eigenmode calculations and eddy current calculations using Biot–Savart representations of the dynamic gradient field. In addition, a parallelism factor expressed in terms of the shield vibrations is defined to measure the coupling between the distinct cylinders.

It is found that the strength of the background field strongly influences the coupling of the distinct shields, which strongly increases the parallelism of the shield vibrations. Furthermore, modal expansion and participation factors are significantly influenced, caused by frequency shifts due to magnetic stiffening and increased magnetic coupling.

The current work is limited to the modal expansions of a single shield. This needs to be extended in the future as comparison of modal expansion factors and finite element simulation indicate.

The defined factors estimating parallelism and modal participation in magneto-mechanical coupling are original work and studied for the first time.

Traditional employment practices since the Second World War had usually ensured job security for a company’s workforce. However, the increasingly competitive environment and the restructuring of companies in the 1980s and 1990s have made this practice impossible to continue; therefore, layoffs have become a fact of life for employees in an increasing number of industries. The purpose of this study was to examine attitudes in two employment environments, one in which temporary workers were used to shield permanent employees from layoffs and another in which layoff decisions were made without regard to permanent or temporary status. Specifically, examination was made of the relationships among perceived organizational support (POS), organizational commitment, and intention to quit, and the relative levels of these variables across two environments and the two classes of workers. It was found that, as expected, the relationships among the commitment variables and intention to quit were similar within both environments. Also, as expected, levels of commitment in the “shield” environment were higher than in the “layoff” environment; and POS was higher among temporary employees in the “shield” environment than among permanent workers in the “layoff” environment. A particularly interesting finding was that, in the “layoff” environment, POS among temporary workers was higher than among permanent workers.

This is a selective annotated bibliography of the literature on Christopher Columbus from 1970 to 1989. The subject is particularly relevant considering the approach of the Quincentenary of the “discovery” of America in 1992. For that same reason, there has been an outpouring of literature on the subject since 1990, a significant subset of which contributes to are interpretation of Columbus the man, his voyages, and their impact on the new world. It is hoped that this more recent literature will be part of a subsequent annotated bibliography.

Powder bed fusion processes are common due to their ability to build complex components without the need for complex tooling. While additive manufacturing has gained increased interest in industry, academia and government, flaws are often still generated during the deposition process. Many flaws can be avoided through careful processing parameter selections including laser power, hatch spacing, spot size and shielding gas flow rate. The purpose of this paper is to study the effect of shielding gas flow on vapor plume behavior and on final deposition quality. The goal is to understand more fully how each parameter affects the plume and deposition process.

A filtered-photodiode based sensor was mounted onto a commercial EOS M280 machine to observed plume emissions. Three sets of single tracks were printed, each with one of three gas flow rates (nominal, 75% nominal and 50% nominal). Each set contained single-track beads deposited atop printed pedestals to ensure a steady-state, representative build environment. Each track had a set power and speed combination which covered the typical range of processing parameters. After deposition, coupons were cross-sectioned and bead width and depth were measured. Finally, bead geometry was compared to optical emissions originating in the plume.

The results show that decreasing gas flow rate, increasing laser power or increasing scan speed led to increased optical emissions. Furthermore, decreasing the gas cross-flow speed led to wider and shallower melt pools.

To the best of the authors’ knowledge, this paper is among the first to present a relationship among laser parameters (laser power, scan speed), gas flow speed, plume emissions and bead geometry using high-speed in situ data in a commercial machine. This study proposes that scattering and attenuation from the plume are responsible for deviations in physical geometry.

Global sourcing can bring many benefits to organisations, but it can also expose them to a number of risks. The purpose of this study is to understand how managers assess global sourcing risks across the entire supply chain and what actions they take to mitigate those risks.

A multiple case study approach was used, involving 15 cases in seven different industries. Each case consisted of interviews with managers directly involved in the global sourcing decision, supported by documentary evidence. A cross‐case analysis was conducted to analyse patterns across different industries.

The study revealed that most companies do not have a structured supply chain risk management and mitigation system. Nevertheless they do use a number of informal approaches to cope with risk. The paper proposes that a multidisciplinary approach is required when dealing with global sourcing risks. It presents a classification of risks covering four categories: supply risk, process and control risks, environmental and sustainability risks, and demand risks.

The paper addresses a research gap concerning managers' approaches to assessing and mitigating supply chain risk in a global context. In this context, this study proposes a new categorisation for global sourcing risks and offers a characterisation of global sourcing risk mitigation strategies applicable to different industries.

The COVID-19 pandemic drastically changed safety measures in every industry, including the construction industry. Thus, the construction companies have instituted safety measures at the construction sites to curve the disease’s spread among the workforce. This paper aims to examine the challenges encountered by construction firms in implementing COVID-19 safety measures at construction sites.

A qualitative research approach was adopted for this study using open-ended interview questions to solicit data from 19 construction professionals currently working on a construction project in South Africa. Content analysis with the assistance of an Excel spreadsheet was used to analyse the data collected.

The findings indicate that there are numerous challenges such as ignorance of COVID-19, the supply of poor personal protective equipment (PPEs) by contractors, lack of compliance, sanitising construction materials, difficulty in sharing tools and equipment, public transport usage by workers, superstition (COVID-19 is for a particular group of people), complying with social distancing rules, among others in the implementation of the COVID-19 safety measure at the construction site to curb the spread of the disease among the workers. These challenges have, therefore, hampered their effort to strictly adhere to the safety measures in accordance with the COVID-19 safety protocol at the project sites currently under construction.

The interviewees were construction professionals working in the South African construction industry during the COVID-19 period.

The implication is that, due to the challenges faced in implementing the COVID-19 safety measures, workers on the construction site are not adequately protected from contracting COVID-19. The workers may thus contract the disease at the project sites and transmit it to their families and vice versa, which may have further implications on the spread of the disease within the communities and society.

The study has identified implementation challenges of the COVID-19 safety measures at construction sites of which the construction stakeholders must institute measures to overcome since COVID-19 has become part of our daily life. The study also recommends some preventive measures to the owners of construction companies to help overcome or minimise these COVID-19 safety implementation hurdles to minimise the spread of the disease among the construction site workers.

We discuss the connections between epidemiology models and the search and matching (SAM) approach and draw conclusions about modeling the trade-offs between lockdowns and disease spread. We review the pre-COVID epidemics literature, which was mainly by epidemiologists, and the post-COVID surge in economics papers that use meeting technologies to model the trade-offs. We argue that modeling the decentralized equilibrium with economic trade-offs gives rise to substantially different results from the earlier epidemics literature, but policy action is still welfare-improving because of several externalities.