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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
T. Numakura et al. (19P47)
Fusion Science and Technology | Volume 51 | Number 2 | February 2007 | Pages 343-345
Technical Paper | Open Magnetic Systems for Plasma Confinement | doi.org/10.13182/FST07-A1396
Articles are hosted by Taylor and Francis Online.
The effects of the plasma-confining potentials and the associated radially sheared electric fields on the central-cell electron energy confinement are theoretically and experimentally investigated in the GAMMA 10 tandem mirror. In particular, the scaling of the central-cell electron temperatures with electron-confining potentials is studied on the basis of the local energy-balance equation. The obtained theoretical scaling of electron temperatures with electron-confining potentials is then compared with the experimentally observed relation between these two parameters.Recently, by the use of new 0.5-MW level gyrotrons in the plug region, four-time progress in the formation of the ion-confining potential c including a new record of 3 kV has been achieved in a hot-ion mode having bulk-ion temperature Ti = several keV. In the hot-ion mode, intermittent vortex-like turbulent structures are observed in the case without the gyrotron injections; in this case, radially produced weak shear of electric fields dEr/dr and appreciable transverse losses are observed. However, during the application of electron-cyclotron heatings, the associated potential rise produces a stronger shear in the central cell (dEr/dr = several 10 kV/m2) resulting in the disappearance of such intermittent turbulent vortices with plasma confinement improvement.In order to investigate the effect of the radially sheared electric fields on the electron energy confinement, the radial profiles of the thermal diffusivity are derived from the local power-balance analysis by the use of the data from the following various diagnostics in the above-described hot-ion mode. The obtained radial profiles of radial electric field and thermal diffusivity imply that the reduction of the thermal diffusivity is associated with the radially produced strong shear of electric fields.
