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Former Exelon CEO Chris Crane remembered for “transformational milestones”
Crane
Exelon announced that Chris Crane, the company’s former chief executive, passed away on Saturday in Chicago at the age of 65.
Crane served as the company’s president and CEO from 2012 until his retirement in December 2022. During his tenure, he steered the energy company through several transformational milestones, including the successful mergers with Constellation Energy in 2012 and Pepco Holdings in 2016, creating the largest utility business by customer count in the United States.
In 2022, with the spin-off of Constellation as the generation and retail side of energy business (with the largest U.S. nuclear fleet), Crane led the creation of a stand-alone transmission and delivery energy company.
Taro Ueki
Nuclear Science and Engineering | Volume 160 | Number 2 | October 2008 | Pages 242-252
Technical Paper | doi.org/10.13182/NSE160-242
Articles are hosted by Taylor and Francis Online.
The stationarity diagnostics of source distribution in the iterated-source Monte Carlo computation for nuclear criticality and static nuclear reactor analysis have been studied using relative entropy and the Wilcoxon signed rank sum. Novel aspects of the diagnostics are (a) the relative entropy of permuted and nonpermuted source distributions and (b) a series of differenced relative entropies. Item (a) combined with averaging over random permutations has some smoothing effect on the fluctuation through iteration cycles. The benefit of item (b) is twofold: The differencing works as decorrelation, and the mean in stationarity of a differenced series is exactly zero. Therefore, the Wilcoxon signed rank sum has been applied to check the stationarity of the differenced relative entropy series. Another novel aspect of the diagnostics is the use of a problem-independent number of iteration cycles preceding the current iteration cycle upon the computation of the Wilcoxon signed rank sum. In addition, it has been shown that the progressive relative entropy in previous work can be used and the moving average of the Wilcoxon signed rank sums of its differenced series is a stringent measure of stationarity. Numerical results are presented for two- and three-dimensional modeling of an initial core of pressurized water reactors.