3,810 research outputs found
Traveling wave oscillations in the optical region: a theoretical examination
The interaction of an electron beam with the optical field of a periodically perturbed dielectric thin-film waveguide is considered. When the electron velocity is nearly equal to that of one of the spatial harmonics of the field, a coherent exchange of energy can take place. This interaction, which can lead in principle to a voltage-tunable optical oscillation, is examined in the light of presently available thin-film techniques. An estimate of the oscillation threshold is made
Diversity in Retirement Wealth Accumulation
Examines household wealth by source, such as Social Security, home equity, savings, and defined benefit pensions; how their savings build up with age; and how total wealth accumulations vary by income, education, and race/ethnicity. Explores implications
The effectiveness of teamwork training on teamwork behaviors and team performance : A systematic review and meta-analysis of controlled interventions
The objective of this study was to conduct a systematic review and meta-analysis of teamwork interventions that were carried out with the purpose of improving teamwork and team performance, using controlled experimental designs. A literature search returned 16,849 unique articles. The meta-analysis was ultimately conducted on 51 articles, comprising 72 (k) unique interventions, 194 effect sizes, and 8439 participants, using a random effects model. Positive and significant medium-sized effects were found for teamwork interventions on both teamwork and team performance. Moderator analyses were also conducted, which generally revealed positive and significant effects with respect to several sample, intervention, and measurement characteristics. Implications for effective teamwork interventions as well as considerations for future research are discussed
Standing Firm: Maine’s Delegation to Congress during The Secession Crisis of 1860-1861
In the years leading up to the Civil War, many Americans in both the North and the South considered it inevitable that a war between the sections would occur. Historians have debated this idea ever since. Could the war have been avoided? Was a compromise between the sections of the country possible? In this article, the author examines the role played by Maine’s congressional delegation in resisting compromise during the Great Secession Winter of 1860-1861. The author is a graduate of the University of Maine, with master’s degrees in education (1979) and Arts (History-1991). He served as the lead consulting curator during the planning and development of the National Civil War Museum in Harrisburg, Pennsylvania. He is the author of several books and articles about the Civil War, including the forthcoming Mantled in Smoke and Fire: Maine Regiments at Gettysburg (Spring 2014). He is currently the executive director of the Birmingham History Center in Birmingham, Alabama
The Attempt to Repeal Maine’s Personal Liberty Laws
Many issues divided the nation before the Civil War. One in particular involved the passage of Personal Liberty laws in the northern states, which circumscribed the conduct of officials handling fugitive slaves. While Maine was not a prominent destination for runaway slaves, its Personal Liberty laws, redrafted in 1857 by the state\u27s new Republican majority, were particularly forceful and therefore particularly odious to Southern planters. As the secession crisis loomed, Maine reconsidered the constitutionality of the laws and their political expediency: Would the state bend to the needs of national reconciliation? Mr. Desmond, born in Island Falls, Maine, received M.A. degrees in education (1979) and History (1991) from the University of Maine and taught for twelve years in Maine public schools. He has published several articles (New England Quarterly, Tennessee Historical Quarterly, Chattanooga Regional Historical Journal), and a book: Images Of America: Chattanooga. A resident of Lookout Mountain, Georgia he is currently employed as Curator of Collections for the Chattanooga Regional History Museum
Development of high speed power thyristor: The gate assisted turn-off thyristor
A high speed power switch with unique turn-off capability was developed. This gate-assisted turn-off thyristor was rated at 609 V and 50 A with turn-off times of 2 microsec. Twenty-two units were delivered for evaluation in a series inverter circuit. In addition, test circuits designed to relate to the series inverter application were built and demonstrated
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