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The purpose of this paper is to carry out an extensive numerical study in order to understand the flow structures and the resulting noise generated by a supersonic impinging jet on a flat plate. One of the parameters varied in this study is the distance between the jet exit plane and the flat plate.

Because of the unsteady nature of the problem a time-dependent computation is carried out using the detached eddy simulation turbulence model. The OVERFLOW 2 CFD code was used with a highly resolved grid and small time steps.

The authors found that as the separation distance increases, the dominant frequencies in the noise spectrum decrease. In addition, the relative strength of the various frequencies to each other changes with changing distance, indicating the changing modes of the jet. The CFD results indicate a strong interaction between the acoustic waves emanating from the impingement plate and the jet plume. This feedback mechanism is responsible for destabilizing the jet shear layer leading to the jet changing modes. The computed near field spectra, convection velocities of the jet vortical structures and mean jet centerline velocity profile are in good agreement with experimental measurements. The results also show very high sound pressure levels all over the impingement plate but especially near the impingement point. These levels, if sustained, are detrimental to both human operators as well as the surrounding structures.

Given the large-scale nature of the computations carried out, it is very costly to run the computations long enough to collect a good, statistically steady time sample to achieve a low frequency bandwidth resolution. Such a long time sample could actually improve the results in terms of frequency resolution and obtained an even better agreement with experiments. Off course there is always the issue of grid resolution as well, but given the good agreement with experiments that the authors obtained, the authors are confident in their results.

The practical implications of the results the authors obtained are significant in that, the authors now know that hybrid RANS-large eddy simulation methods can be used for this complex, unsteady engineering problems. In addition, the results also show the high noise level both on the impingement surface and in the surroundings of the jet. This could have a negative impact on the structural integrity of the flat surface.

Noisy environments are never desirable anywhere especially in places where human operations take place. Therefore, given the high noise levels obtained in the simulations and confirmed by experiments, any human presence around the jet will be harmful to hearing and precautions need to be taken.

This is a physics-based study; i.e. understanding the physical phenomena involved in supersonic jet impingement. Of particular interest is the interaction of the jet shear layer with the acoustic waves emanating from the impingement area. This feedback loop is found to be responsible for intensifying the instability of the jet shear layer.

This chapter shares the findings of a research study that investigated how organizations managed critical incidents that had the potential for dramatic economic impact and why those organizations chose to pursue certain issues. The findings expose organization identity’s role in stabilizing organizations. Understanding this role creates an opportunity to improve organization change efforts by examining and understanding a subject’s organization identity. Armed with this understanding, a change agent may design interventions in such a way as to align with identity or, when necessary, to specifically alter identity.

The purpose of this paper is to encourage ethical discernment as a dimension of business decision‐making.

Development of ethical discernment and a process of ethical evaluation in the analysis of decisions made by the auditors and management in the Adelphia accounting scandal.

The paper finds that accounting may benefit from an increased focus on ethical discernment and ethical behavior. Ethical behavior may help restore trust and confidence in the capital market system and reduce fraudulent financial reporting.

This paper presents an alternative to regulation for restoring trust in the financial oversight function.

To develop theoretical frameworks to discuss high profile scandals, where responsible accountants and other executives could have saved themselves, many investors and others severe personal and financial loss by considering the costs of improper or immoral behavior. These cases emphasize the importance of ethics driving accountants' decisions.

The paper discusses these ethical lapses in light of applying Kohlberg's models, biblical examples from the Old and New Testaments and the Koran, and other ethical systems.

The paper shows that this concept is not new. Throughout history, people have taken actions that cost them their freedom, their money and most importantly, their good names. Upon reflection, many of these people are astounded at the seriousness of their action given what little they had to gain from continued involvement. In reinforcing lessons that should be learned from cases of business malfeasance and highlighting many well‐known accounting and other scandals, we develop recurrent themes in the nature of business scandals and show that many people are responsible for or complicit in the malfeasance. These individuals could have prevented the fraud or minimized any adverse impact if they had considered their behavior ex ante. We show that the employees portrayed demonstrated very low‐levels of ethical development and seemed to underestimate the probability of getting caught and the resulting punishment. We also elicit many reasons from several viewpoints for not becoming involved in fraud.

It is hoped that the next generation of business leaders and middle level staff alike will consider the results/messages of this paper when faced with ethical dilemmas.

The paper concludes that the best internal control in a business structure remains the hiring and training of morally upstanding employees and managers who recognize the values of their good names before temptations arise. Incentive plans can encourage ethical behavior.

Practitioners must consider fully the potential consequences of their actions no matter how small the perceived probability of a bad outcome.

This article examines how contact with the police led to the death of Michael Brown (an unarmed 18-year-old Black teenager from Ferguson, Missouri, who was shot and killed during an altercation with a police officer). And, how Darren Wilson (the White police officer from the Ferguson Police Department who shot and killed Michael Brown) was portrayed in mainstream newspaper articles covering the story of Brown’s death.

Using both frame analysis and Hall’s framework of discursive domains for organizing and making sense of events in social life, we analyzed news coverage of Brown in three of the top circulating daily newspapers in the US: The New York Times, Los Angeles Times, and The Washington Post. The Lexis Nexis database was used to retrieve a set of newspapers using the search term “Michael Brown.” Articles from the three leading newspapers were collected from the day the event occurred, August 9, 2014, through the end of the year, December 31, 2014.

The news articles used in this study were mostly written with an episodic frame. The articles presenting the socioeconomic background of Brown and Wilson were described as profiles on each individual and the neighborhood they came from, rather than a discussion about where they fell on the economic structure of this country and the larger, upstream forces that might influence those positions. The feelings and attitudes of the reader are also likely to be influenced by details included in the articles and how they were presented.

The findings contribute to the broader literature looking at the relationships between police and Black communities. Public health can play a role in advocating and facilitating programs that build better linkages between police and community. The public health field can take a leadership role in holding the news media accountable when they are engaging in frenetic inaction. Only by having difficult and challenging conversations that examines the upstream causes of violence and deaths like Brown’s, can we make progress in preventing them.

The purpose of this paper is to demonstrate the ability to researchers of using design of experiments (DoE) as a structured and systematic approach to performing systematic literature reviews. The authors demonstrate a simple case study illustrating the application of DoE in executing a systematic literature review on two popular topics in higher education: academic leadership and Lean Six Sigma.

The methodology involves the systematic literature review of linking academic leadership with terms such as Lean, Six Sigma, Total Quality Management, Maturity Model and Continuous Improvement. The main tool used to structure the systematic literature review is a Taguchi Orthogonal Array design, specifically an L16 grid and the method is verified by conducting another review, replacing the term academic leadership with simply leadership.

The approach identified at first no research papers linking the terms; however, when academic leadership was replaced with university, 19 research papers where discovered. The verification exercise, linking just leadership with the other search string generated over 1,000 results – demonstrating that the tool can find large volumes of articles if they exist, the search was completed for a ten year time frame – 2004 to 2014.

The case study focussed on a field which is known to have little current research and the verification exercise deliberately targeted a known large body of research. The authors will continue to use the approach and refine the technique over time.

This approach would help any researcher despite of their discipline to identify opportunities and gaps in the current literature.

The paper shows how DoE can be used in an academic research-based process. No other literature review approach currently exists which uses Taguchi approach to DoE to filter the search criteria.

This chapter examines the framing of the Black Lives Matter (BLM) Movement in mainstream media. An analytic sample of 4,303 articles collected from the Dow Jones Factiva database reveals variation in depth, breadth, and intensity of BLM coverage in the following newspapers between 2012 and 2016: The St. Louis Post-Dispatch, The New York Times, The Washington Post, The Wall Street Journal, and Al Jazeera English. We review contemporary literature on racial inequality and employ Media Framing and Critical Race Theory to discuss the implications of our findings on public perceptions, future policy formation, and contemporary social protest worldwide.

Michael E. Brown's book, The Concept of the Social in Uniting the Humanities and Social Sciences, demonstrates that prominent attempts to account for the social dimension of human affairs rely on an unstated notion of a “course of activity,” that is diametrically opposed to the conceptualization of sociality that is presumably intended to realize it. I want to focus on the idea of a “course of activity” in order to locate his work in and clarify its importance to the development of dialectical reason from Heraclitus through Hegel and beyond. Of special importance is the bearing of his research on the critique of contemporary theories of agency and sociality, and, since considerable attention has been paid, in this regard, to the arts and humanities, some of what I will say about this refers to art and its avant-garde moments—-particularly in my work on Dada and Brown's account of two avant-garde theatrical performances. 

This chapter examines what is entailed by separating agency from individuality and what it means for the idea of a “course of activity,” (going on) and its relation to the concept of sociality. This also bears on questions of ontology, as Brown's course of activity is generative and nonrepeatable. The course of activity and nonrepeatability are linked to both avant-garde practice and theoretical notions that reframe our temporal understandings. These include the avant-garde of dada and surrealism, and the reformulations of bourgeois time of Jean Duvignaud, Walter Benjamin, Ernst Bloch, and Jean-Paul Sartre. The question raised here is that of a teleological understanding—how we link the present course of activity with future events.