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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Jaakko Leppänen
Nuclear Science and Engineering | Volume 174 | Number 3 | July 2013 | Pages 318-325
Technical Paper | doi.org/10.13182/NSE12-54
Articles are hosted by Taylor and Francis Online.
This paper presents a methodology for applying continuously varying density distributions in Monte Carlo particle transport simulation. The capability is implemented in the Serpent 2 code, as part of an effort for developing a universal multiphysics interface for the coupling of Monte Carlo neutronics to thermal hydraulics and fuel performance codes. The method is based on rejection sampling of particle path lengths, but despite its close resemblance to the Woodcock delta-tracking method, the routine can be used with conventional surface tracking as well. The modified tracking routine is put to the test in a simple boiling water reactor pin-cell calculation with continuously changing void distribution in the coolant channel.