Recalculation of power costs for the CANDU reactor

"NYO-9716."AT(30-1)-207

Behavioral, morphological, and ecological trait evolution in two clades of New World Sparrows (Aimophila and Peucaea, Passerellidae)

Copyright 2020 Cicero et al. The New World sparrows (Passerellidae) are a large, diverse group of songbirds that vary in morphology, behavior, and ecology. Thus, they are excellent for studying trait evolution in a phylogenetic framework. We examined lability versus conservatism in morphological and behavioral traits in two related clades of sparrows (Aimophila, Peucaea), and assessed whether habitat has played an important role in trait evolution. We first inferred a multi-locus phylogeny which we used to reconstruct ancestral states, and then quantified phylogenetic signal among morphological and behavioral traits in these clades and in New World sparrows more broadly. Behavioral traits have a stronger phylogenetic signal than morphological traits. Specifically, vocal duets and song structure are the most highly conserved traits, and nesting behavior appears to be maintained within clades. Furthermore, we found a strong correlation between open habitat and unpatterned plumage, complex song, and ground nesting. However, even within lineages that share the same habitat type, species vary in nesting, plumage pattern, song complexity, and duetting. Our findings highlight trade-offs between behavior, morphology, and ecology in sparrow diversification

A generalized study of the breeding potential of large heavy water moderated power reactors fueled with thoria and urania

"January 1967.""MIT-2073-5."Also issued as a Ph. D. thesis by the first author and supervised by the second and third authors, Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1966Includes bibliographical references (pages 324-328)U.S. Atomic Energy Commission contract AT(30-1)-207

The effect of refueling decisions and engineering constraints on the fuel management for a pressurized water reactor

Also issued as a Ph. D. thesis in the Dept. of Nuclear Engineering, 1974Work sponsored by Commonwealth Edison CompanyIncludes bibliographical references (pages 383-385)M.I.T. DSR Project no. 7210

Incremental costs and optimization of in-core fuel management of nuclear power plants

"Issued: February 1973."Also issued as an Sc. D. thesis by the first author and supervised by the second and third authors, MIT, Dept. of Nuclear Engineering, 1973Includes bibliographical references (pages 250-251)This thesis is concerned with development of methods for optimizing the energy production and refuelling decision for nuclear power plants in an electric utility system containing both nuclear and fossil-fuelled stations. The objective is to minimize the revenue requirements for refuelling the power plants during the planning horizon; the decision variables are the energy generation, reload enrichment and batch fraction for each reactor cycle; the constraints are that the customer's load demand, as well as various other operational and engineering requirements be satisfied. This problem can be decomposed into two sub-problems. The first sub-problem is concerned with scheduling energy between nuclear reactors which have been fuelled in an optimal fashion. The second sub-problem is concerned with optimizing the fuelling of nuclear reactors given an optimized energy schedule.These two sub-problems when solved iteratively and interactively, would yield an optimal solution to the original problem. The problem of optimal energy scheduling between nuclear reactors can be formulated as a linear program. The incremental cost of energy is required as input to the linear program. Three methods of calculating incremental cost are considered: the Rigorous Method, based on the definition of partial derivativesis accurate but time consuring; the Inventory Value Method and the Linearization Method, based respectively on equations of inventory evaluation and linearization, are less accurate, but efficient. The latter two methods are recommended for the early stages of optimization. The problem of optimizing the fuelling of nuclear reactors has been solved for two cases: the special case of steady state operation, and the general case of nonsteady- state operation. The steady-state case has been solved by simple graphic techniques.The results indicate that reactors should be refuelled with as small a batch fraction as allowed by burnup constraints. The non-steady case has been solved by polynomial approximation, in which the objective function as well as the constraints are approximated by a sum of polynomials. The results indicate that the final selection of an optimal solution from a set of sub-optimal solutions is primarily based on engineering considerations, and not on economics considerations

The effect of uranium-236 and neptunium-237 on the value of uranium as feed for pressurized water power reactors

"December 1967."Volume 2 contains appendicesMIT-2073-6Includes bibliographical referencesU. S. Atomic Energy Commission under contract AT(30-1)-207

The Effect of uranium-236 and neptunium-237 on the value of uranium used as feed for thermal power reactors

Statement of responsibility on title page reads: Manson Benedict, David J. Bauhs, Terence C. Golden and Edward A. Mason"June 30, 1968.""MIT-2073-7."Includes bibliographical references (pages 183-184)United States Atomic Energy Commission contract AT(30-1)-207