162 research outputs found
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Ice-condenser aerosol tests
This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between {approximately}0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m{sup 3}/s resulted in stable thermal stratification whereas flows less than 0.1 m{sup 3}/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs
Auditory but Not Audiovisual Cues Lead to Higher Neural Sensitivity to the Statistical Regularities of an Unfamiliar Musical Style
It is still a matter of debate whether visual aids improve learning of music. In a multisession study, we investigated the neural signatures of novel music sequence learning with or without aids (auditory-only: AO, audiovisual: AV). During three training sessions on 3 separate days, participants (nonmusicians) reproduced (note by note on a keyboard) melodic sequences generated by an artificial musical grammar. The AV group (n = 20) had each note color-coded on screen, whereas the AO group (n = 20) had no color indication. We evaluated learning of the statistical regularities of the novel music grammar before and after training by presenting melodies ending on correct or incorrect notes and by asking participants to judge the correctness and surprisal of the final note, while EEG was recorded. We found that participants successfully learned the new grammar. Although the AV group, as compared to the AO group, reproduced longer sequences during training, there was no significant difference in learning between groups. At the neural level, after training, the AO group showed a larger N100 response to lowprobability compared to high-probability notes, suggesting an increased neural sensitivity to statistical properties of the grammar; this effect was not observed in the AV group. Our findings
indicate that visual aids might improve sequence reproduction while not necessarily promoting better learning, indicating a potential dissociation between sequence reproduction and learning. We suggest that the difficulty induced by auditory-only input during music training might enhance cognitive engagement, thereby improving neural sensitivity to the underlying statistical properties of the learned material
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Polish-American Children's Hospital in Krakow, Poland
In late 1990 staff from the US Department of Energy's Office of Technical and Financial Assistance identified the Polish-American Children's Hospital as a potential site for application of DOE expertise to reduce the Hospital's energy requirements. Visits to the hospital in the fall and winter of 1991--1992 provided initial scoping of the energy related activities that would be supported by DOE. In addition to reducing energy requirements, the Hospital staff expressed a need for assistance in the areas of power quality and medical waste incineration. Subsequently, a power quality study supported by the Electric Power and Research Institute has been initiated and medical waste incineration will be provided by a Polish organization. The resulting scope of work for this effort is to survey the Hospital's thermal energy supply and demand systems to identify no-cost and low-cost measures that will reduce the Hospital's energy requirements. Applicable measures would then be demonstrated in the Hospital through a partnership with US and Polish organizations and a sister hospital in the United States
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Fort Lewis natural gas and fuel oil energy baseline and efficiency resource assessment
The mission of the US Department of Energy (DOE) Federal Energy Management Program (FEMP) is to lead the improvement of energy efficiency and fuel flexibility within the federal sector. Through the Pacific Northwest Laboratory (PNL), FEMP is developing a fuel-neutral approach for identifying, evaluating, and acquiring all cost-effective energy projects at federal installations; this procedure is entitled the Federal Energy Decision Screening (FEDS) system. Through a cooperative program between FEMP and the Army Forces Command (FORSCOM) for providing technical assistance to FORSCOM installations, PNL has been working with the Fort Lewis Army installation to develop the FEDS procedure. The natural gas and fuel oil assessment contained in this report was preceded with an assessment of electric energy usage that was used to implement a cofunded program between Fort Lewis and Tacoma Public Utilities to improve the efficiency of the Fort's electric-energy-using systems. This report extends the assessment procedure to the systems using natural gas and fuel oil to provide a baseline of consumption and an estimate of the energy-efficiency potential that exists for these two fuel types at Fort Lewis. The baseline is essential to segment the end uses that are targets for broad-based efficiency improvement programs. The estimated fossil-fuel efficiency resources are estimates of the available quantities of conservation for natural gas, fuel oils [number sign]2 and [number sign]6, and fuel-switching opportunities by level of cost-effectiveness. The intent of the baseline and efficiency resource estimates is to identify the major efficiency resource opportunities and not to identify all possible opportunities; however, areas of additional opportunity are noted to encourage further effort
Priming Analogical Reasoning with False Memories
Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems
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Assessment of concentration mechanisms for organic wastes in underground storage tanks at Hanford
Pacific Northwest Laboratory (PNL) has conducted an initial conservative evaluation of physical and chemical processes that could lead to significant localized concentrations of organic waste constituents in the Hanford underground storage tanks (USTs). This evaluation was part of ongoing studies at Hanford to assess potential safety risks associated with USTs containing organics. Organics in the tanks could pose a potential problem if localized concentrations are high enough to propagate combustion and are in sufficient quantity to produce a large heat and/or gas release if in contact with a suitable oxidant. The major sources of oxidants are oxygen in the overhead gas space of the tanks and sodium nitrate and nitrite either as salt cake solids or dissolved in the supernatant and interstitial liquids
Inquiry pedagogy to promote emerging proportional reasoning in primary students
Proportional reasoning as the capacity to compare situations in relative (multiplicative) rather than absolute (additive) terms is an important outcome of primary school mathematics. Research suggests that students tend to see comparative situations in additive rather than multiplicative terms and this thinking can influence their capacity for proportional reasoning in later years. In this paper, excerpts from a classroom case study of a fourth-grade classroom (students aged 9) are presented as they address an inquiry problem that required proportional reasoning. As the inquiry unfolded, students' additive strategies were progressively seen to shift to proportional thinking to enable them to answer the question that guided their inquiry. In wrestling with the challenges they encountered, their emerging proportional reasoning was supported by the inquiry model used to provide a structure, a classroom culture of inquiry and argumentation, and the proportionality embedded in the problem context
Weighing up Exercises on Phrasal Verbs: Retrieval Versus Trial-And-Error Practices
EFL textbooks and internet resources exhibit various formats and implementations of exercises on phrasal verbs. The experimental study reported here examines whether some of these might be more effective than others. EFL learners at a university in Japan were randomly assigned to four treatment groups. Two groups were presented first with phrasal verbs and their meaning before they were prompted to retrieve the particles from memory. The difference between these two retrieval groups was that one group studied and then retrieved items one at a time, while the other group studied and retrieved them in sets. The two other groups received the exercises as trial-and-error events, where participants were prompted to guess the particles and were subsequently provided with the correct response. One group was given immediate feedback on each item, while the other group tackled sets of 14 items before receiving feedback. The effectiveness of these exercise implementations was compared through an immediate and a 1-week delayed post-test. The best test scores were obtained when the exercises had served the purpose of retrieval, although this advantage shrank in the delayed test (where scores were poor regardless of treatment condition). On average 70% of the post-test errors produced by the learners who had tackled the exercises by trial-and-error were duplicates of incorrect responses they had supplied at the exercise stage, which indicates that corrective feedback was often ineffective
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