ACTINIDE BURNING IN A LEAD-BISMUTH-COOLED CRITICAL FAST REACTOR WITH ECONOMIC ELECTRICITY GENERATION *
A Lead Bismuth-cooled fast reactor concept for actinide burning and low-cost electricity production and excellent safety characteristics is proposed. The concept employs metallic thoriumbased fuel (Th-U-Pu-MA-Zr) in a 700 MWth core. The transuranics destruction rate per MWth-yr is 66% that of an accelerator-driven system using the same initial transuranics composition in fertile-free fuel. Coolant void reactivity mitigation is achieved through the use of streaming fuel assemblies and both the Doppler and fuel thermal expansion feedback are negative. The small negative fuel temperature and coolant temperature reactivity coefficients and negative core radial expansion coefficient provide self-regulating characteristics, so that the reactor is capable of inherent shutdown in major transients without scram, as in the Integral Fast Reactor (IFR). * This project is supported by an INEEL Laboratory Directed Research and Development Project.
Medium-Power Lead-Alloy Reactors: Missions for This Reactor Technology
Abstract A multiyear project at the Idaho National Engineering and Environmental Laboratory and the Massachusetts Institute of Technology investigated the potential of medium-power lead-alloy–cooled technology to perform two missions: (1) the production of low-cost electricity and (2) the burning of actinides from light water reactor (LWR) spent fuel. The goal of achieving a high power level to enhance economic performance simultaneously with adoption of passive decay heat removal and modularity capabilities resulted in designs in the range of 600-800 MW(thermal), which we classify as a medium power level compared to the lower [˜100 MW(thermal)] and higher [2800 MW(thermal)] power ratings of other lead-alloy–cooled designs. The plant design that was developed shows promise of achieving all the Generation-IV goals for future nuclear energy systems: sustainable energy generation, low overnight capital cost, a very low likelihood and degree of core damage during any conceivable accident, and a proliferation-resistant fuel cycle. The reactor and fuel cycle designs that evolved to achieve these missions and goals resulted from study of the following key trade-offs: waste reduction versus reactor safety, waste reduction versus cost, and cost versus proliferation resistance. Secondary trade-offs that were also considered were monolithic versus modular design, active versus passive safety systems, forced versus natural circulation, alternative power conversion cycles, and lead versus lead-bismuth coolant. These studies led to a selection of a common modular design with forced convection cooling, passive decay heat removal, and a supercritical CO2 power cycle for all our reactor concepts. However, the concepts adopt different core designs to optimize the achievement of the two missions. For the low-cost electricity production mission, a design approach based on fueling with low enriched uranium operating without costly reprocessing in a once-through cycle was pursued to achieve a long operating cycle length by enhancing in-core breeding. For the actinide-burning mission three design variants were produced: (1) a fertile-free actinide burner, i.e., a single-tier strategy, (2) a minor actinide burner with plutonium burned in the LWR fleet, i.e., a two-tier strategy, and (3) an actinide burner with characteristics balanced to also favor economic electricity production.
Emotional and social intelligence assessment model for student character reinforcement
PurposeThe purpose of this study is to help teachers resolve the difficulties in assessing the students' characters through the development of valid, reliable, goodness-of-fit statistic instrument of emotional and social intelligence assessment for elementary school students.Design/methodology/approachThis study used a research and development model from Plomp with five phases, such as investigation, design, realization, testing and implementation. The research subjects were 345 students of class IV amongst 20 elementary schools in Yogyakarta. Data collection used questionnaires, documentation, interviews, Forum Group Discussion and an observation. Data analysis used descriptive analysis, Aiken's V, exploratory factor analysis and confirmatory factor analysis formulae.FindingsThe research study helps solve the difficulties of teachers in assessing emotional and social intelligence, which have previously been in only one area of psychomotor. The design of emotional and social intelligence assessment instruments is made from three domains of character, namely, cognitive, affective and psychomotor. The form of the instrument is non-test in three variations. The construct of social and emotional intelligence assessment for a character reinforcement has met the validity, reliability and goodness-of-fit statistic.Research limitations/implicationsThis study explains that the Emotional and Social Intelligence (ESI) model is applied for measuring cognitive, affective and psychomotor in children. This study proves that the ESI model is a comprehensive assessment model for evaluating the children's soft skills, includes (1) personal abilities: the ability to make rational decisions, the ability to design the future and (2) social skills: the ability to work together and the ability to understand other people.Practical implicationsTeachers can measure and determine the condition of children's soft skills by operating the ESI model. Based on the knowledge of the correct soft skill conditions, the teacher can adjust the teaching materials and teaching methods that would improve the child's soft skills regarding to their respective conditions. Mastering these soft skills will affect the children's capability in facing the challenge in the upcoming society's life.Originality/valueThe novelty of this study is the design model of the emotional and social intelligence assessment instrument developed comprehensively and practically as it is created from three domains of character and three forms of non-test questions, so that the assessment is not mechanical, and easily practiced by users.