5,809 research outputs found
Effective coastal boundary conditions for dispersive tsunami propagation
We aim to improve the techniques to predict tsunami wave heights along the coast. The modeling of tsunamis with the shallow water equations has been very successful, but is somewhat simplistic because wave dispersion is neglected. To bypass this shortcoming, we use the (linearized) variational Boussinesq model derived by Klopman et al. [J. Fluid Mech. 657, 36--63, 2010]. Another shortcoming is that the complicated interactions between incoming and reflected waves near the shore are usually simplified by a fixed wall boundary condition at a certain shallow depth contour. To alleviate this shortcoming, we explore and present in one spatial dimension a so-called effective boundary condition (EBC). From the deep ocean to the seaward boundary, i.e., the simulation area, we model wave propagation numerically. Given the measurements of the incoming wave at the seaward boundary, we model the wave dynamics towards the shoreline analytically, based on shallow water theory and the Wentzel-Kramer-Brillouin (WKB) approximation, as well as extensions to the dispersive, Boussinesq model. The reflected wave is then influxed back into the simulation area using the EBC. The coupling between the two areas, one done numerically and one analytically, via the EBC is handled using variational principles, to preserve the overall energy in both areas. We verify and validate our approach in a series of numerical test cases of increasing complexity, including a case akin to tsunami propagation to the coastline at Aceh, Sumatra, Indonesia
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Hip Arthroscopic Surgery for Femoroacetabular Impingement: A Prospective Analysis of the Relationship Between Surgeon Experience and Patient Outcomes.
Background:Hip arthroscopic surgery is a rapidly growing procedure, but it may be associated with a steep learning curve. Few studies have used patient-reported outcome (PRO) surveys to investigate the relationship between surgeon experience and patient outcomes after the arthroscopic treatment of femoroacetabular impingement (FAI). Hypothesis:Patients undergoing hip arthroscopic surgery for the treatment of FAI in the early stages of a surgeon's career will have significantly worse outcomes and longer procedure times compared with patients treated after the surgeon has gained experience. Study Design:Cohort study; Level of evidence, 2. Methods:Patients undergoing hip arthroscopic surgery for FAI and labral injuries were prospectively enrolled during a sports medicine fellowship-trained surgeon's first 15 months of practice. Patients were stratified into an early group, consisting of the first 30 consecutive cases performed by the surgeon, and a late group, consisting of the second 30 consecutive cases. Radiographic and physical examinations were performed preoperatively and postoperatively. PRO surveys, including the 12-item Short Form Health Survey (SF-12), the modified Harris Hip Score (mHHS), and the Hip disability and Osteoarthritis Outcome Score (HOOS), were administered preoperatively and at a minimum of 1 year postoperatively. Results:There was no difference between the early and late groups for patient age (37.2 ± 11.5 vs 35.3 ± 10.8 years, respectively; P = .489), body mass index (25.6 ± 4.0 vs 25.1 ± 4.5 kg/m2, respectively; P = .615), or sex (P = .465). There was a significantly increased procedure time (119.3 ± 21.0 vs 99.0 ± 28.6 minutes, respectively; P = .002) and traction time (72.7 ± 21.4 vs 59.0 ± 16.7 minutes, respectively; P = .007) in the early group compared with the late group. Mean postoperative PRO scores significantly improved in both groups compared with preoperative values for all surveys except for the SF-12 mental component summary. No differences were found in PRO score improvements or complication rates between the early and late groups. Conclusion:The total procedure time and traction time decrease after a surgeon's first 30 hip arthroscopic surgery cases for FAI and labral tears, but patient outcomes can similarly improve regardless of surgeon experience in the early part of his or her career
Assimilation, Acculturation, and the Law: Solving a âProblemâ Like Sharâia
An unexpected development in the English legal system involves Muslim womenâs use of legally binding Sharâia councils to protect their autonomy, marital security, and property rights. Although scholars and political commentators alike have voiced concerns that Muslim women will be treated unfairly in these councils, there is some indication that women have become adept at navigating this plural legal landscape and that they have often managed to secure better outcomes from Sharâia family law than from English courts. Over 80 Sharâia tribunals have been established to issue legally binding decisions on divorce, child custody, inheritance, and other areas of family law. My paper investigates the ways in which Muslim women living in England navigate secular and religious systems of law, and will compare decisions made by English family courts to those made in Sharâia councils. In so doing, I will suggest that Sharâia law may be proliferating in England in part because it affords divorced Muslim women better outcomes than English family law
Career trajectory and leadership: the role of personal adversity
Adversity is part of life and certainly contributes to human development. This study seeks to explore the impact of personal adversity on career trajectory and leadership. A qualitative study based on 12 interviews with a narrative approach is presented. Key themes were identified among high-level executives around career evolution, perception of leadership, and how those experiences impacted their way of leading. The study concludes with a brief discussion of limitations and the findings that raise questions for additional research and provide some support for leadership and career development, counseling, and training
Do Formal Mediation Programs Work in the Settlement of Employee-Employer Disputes?
People spend an unbelievable amount of their time at work. Work relationships are often very intimate and personal. Because of this, many hostilities and frustrations arise from the workplace and the personal relationships that are formed there. Most people leave their jobs because of their supervisor or team leader. âBasically, itâs a lack of trust, of communication, of relevant and timely feedback, of appreciation, of fair treatment and of information.â These tribulations often create matters that can be mediated successfully. âPersonal feelings of worth and personal satisfaction seem to be essential to maintain a productive workforce.â Unhappy workers are not as successful as those that are content with their working environment. A workplace sees much more achievement in their workers if there is a mediation practice created. The nature of the workplace makes the style of mediation much more beneficial the typical adversarial position taking found in traditional litigation. Mediation is a very useful tool that can be implemented in many disputes that arise from the workplace environment; this paper will focus on the use of mediation in the workplace
The Rhetoric of Louis E. Martin, Godfather of Black Politics
Louis Emanuel Martin, trained as a journalist, worked on behalf of four Democratic presidents: Franklin D. Roosevelt, John F. Kennedy, Lyndon Baines Johnson, and Jimmy Carter. As reporter and editor of two African American newspapers, Martin was uniquely qualified to work with these presidents as a âpublicity aideâ turned rhetorical liaison for African American communities around the nation. His written and spoken works span from the 1930s to the 1990sâsixty plus years of historical interpretationâand include journals, memoirs, newspaper articles, interviews, and over fifty addresses to various audiences. Martinâs public address is key to this rhetorical biography, for his speeches tell stories of race relations in the United States from a largely unexplored perspective. In each epoch, Martinâs voice clearly articulated the concerns of African American communities, including housing, employment, poverty, and lingering discrimination far into the post-civil rights era. Martin believed in the power of the political process, the foundation of which was each personâs obligation to vote. Beyond the voting booth, Martin encouraged his audiences composed of African American government officials, academics, business people, fraternity members, civic groups, and local opinion leaders to become involved in the system to begin to address issues most important to them. Martinâs goal of a genuine âpolitics of inclusionâ was gradually realized with the appointment of Blacks to government and judicial positions they had never before held. Martin chose to remain largely in the background facilitating other peopleâs rise to power. While there is Poinsettâs superb biography on his history, Martinâs work has otherwise been sporadically recognized in texts about civil rights, African American politics, and the black press. To my knowledge, there is no sustained study of his speeches, which have been safely archived for rediscovery by a twenty-first century audience. This project is an act of rhetorical recovery
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