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NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
O. J. Wallace
Nuclear Technology | Volume 113 | Number 1 | January 1996 | Pages 112-122
Technical Note | Radiation Protection | doi.org/10.13182/NT96-A35204
Articles are hosted by Taylor and Francis Online.
Trapezoidal rule and Gauss-Legendre quadratures are representative of the numeric techniques used in integrating over radiation source regions in point-kernel shielding programs. The orders of quadrature selected for such integrations are important since a sparse quadrature may calculate inaccurate results while unnecessarily large orders of quadrature waste computer time. Rules are given for choosing trapezoidal and Gauss quadrature orders for linear, radial, and azimuthal intervals of integration, based on problem geometry and source attenuation. These rules show that for like accuracy, a trapezoidal rule quadrature of order N may be replaced by a Gauss quadrature with order between the square root of N and N/2. Replacing trapezoidal-scale quadratures by lesser order Gauss quadratures can save large amounts of computer time. Gauss quadratures, on the other hand, ideally should be set up individually for detector points in different locations.