Thermal energy transformer

For use in combination with a heat engine, a thermal energy transformer is presented. It is comprised of a flux receiver having a first wall defining therein a radiation absorption cavity for converting solar flux to thermal energy, and a second wall defining an energy transfer wall for the heat engine. There is a heat pipe chamber interposed between the first and second walls having a working fluid disposed within the chamber and a wick lining the chamber for conducting the working fluid from the second wall to the first wall. Thermal energy is transferred from the radiation absorption cavity to the heat engine

Support, Opposition, Emotion and Contentious Issue Risk Perception

Purpose – Research on emotion in the context of risk perception has historically focused on negative emotions, and has emphasized the effect of these negative emotions on the perception of risk amongst those who oppose (rather than support) contentious issues. Drawing on theory, the purpose of this paper is to hypothesize that both positive and negative emotions are correlated with risk perceptions regarding contentious public issues and that this occurs amongst supporters and opponents alike. Design/methodology/approach – The paper explores the relationship between emotions and perceived risk through consideration of the highly contentious case of nuclear energy in Saskatchewan, Canada. The analysis uses data from a representative telephone survey of 1,355 residents. Findings – The results suggest that positive emotions, like negative emotions, are related to nuclear energy risk perceptions. Emotions are related to risk perception amongst both supporters and opponents. Research limitations/implications – The data set’s limited number of emotion measures and single public issue focus, combined with the survey’s cross-sectional design, make this research exploratory in nature. Future research should incorporate multiple positive emotions, explore opposition, and support across a range of contentious public issues, and consider experimental models to assess causal relationships. Practical implications – The paper offers insights into how public sector managers must be cognizant of the emotional underpinnings of risk perceptions amongst both supporters and opponents of contentious public issues. Originality/value – This paper builds on and expands previous work by considering both positive and negative emotions and both supporters and opponents of contentious issues

Exploring Perceptions of Credible Science Among Policy Stakeholder Groups: Results of Focus Group Discussions About Nuclear Energy

How do different stakeholder groups define credible science? Using original qualitative focus group data, this exploratory study suggests that while nuclear energy stakeholder groups consider the same factors when assessing credibility (specifically, knowledge source, research funding, research methods, publication, and replication), groups differ in their assessments of what constitutes expertise, what demonstrates (or reduces) trustworthiness, and the relative prioritization of expertise versus trustworthiness. Overall, these results suggest it is important for science communication to consider audience-specific credibility, and raise questions about the potential impact of both funding sources and predatory journals on the perceived credibility of scientists

Applications of aerospace technology to petroleum extraction and reservoir engineering

Through contacts with the petroleum industry, the petroleum service industry, universities and government agencies, important petroleum extraction problems were identified. For each problem, areas of aerospace technology that might aid in its solution were also identified, where possible. Some of the problems were selected for further consideration. Work on these problems led to the formulation of specific concepts as candidate for development. Each concept is addressed to the solution of specific extraction problems and makes use of specific areas of aerospace technology

Copycat dynamics in leaderless animal group navigation

Background: Many animals are known to have improved navigational efficiency when moving together as a social group. One potential mechanism for social group navigation is known as the 'many wrongs principle', where information from many inaccurate compasses is pooled across the group. In order to understand how animal groups may use the many wrongs principle to navigate, it is important to consider how directional information is transferred and shared within the group. Methods: Here we use an individual-based model to explore the information-sharing and copying dynamics of a leaderless animal group navigating towards a target in a virtual environment. We assume that communication and information-sharing is indirect and arises through individuals partially copying the movement direction of their neighbours and weighting this information relative to their individual navigational knowledge. Results: We find that the best group navigation performance occurs when individuals directly copy the direction of movement of a subset of their neighbours while only giving a small (6%) weighting to their individual navigational knowledge. Surprisingly, such a strategy is shown to be highly efficient regardless of the level of individual navigational error. We find there is little relative improvement in navigational efficiency when individuals copy from more than 7 influential neighbours. Conclusions: Our findings suggest that we would expect navigating group-living animals to predominantly copy the movement of others rather than relying on their own navigational knowledge. We discuss our results in the context of individual and group navigation behaviour in animals

Row Spacing and Productivity of Russian Wild Rye Pastures in Semiarid Environments

To sustain forage yields in dry years in semiarid climates, row spacings \u3e59cm have been recommended for Russian wild rye [Psathyrostachys juncea (Fisch.) Nevski] (Lawrence & Heinrichs, 1968). However, wide row spacings promote weed invasion, soil erosion, and elevated plant crowns resulting in a rough, washboard ground surface (Kilcher, 1961). Jefferson and Kielly (1998) suggested a 30-cm row spacing for optimum sustainable forage yields in Russian wild rye in the semiarid prairie region of Canada. This study aimed to evaluate the relationship between row spacing and productivity of Russian wild rye at two semiarid sites near Mandan, in the northern Great Plains region of the USA (46º 48\u27 N latitude, 100º 55\u27 W longitude)

Assessing the controllability of Arctic sea ice extent by sulfate aerosol geoengineering

In an assessment of how Arctic sea ice cover could be remediated in a warming world, we simulated the injection of SO2 into the Arctic stratosphere making annual adjustments to injection rates. We treated one climate model realization as a surrogate “real world” with imperfect “observations” and no rerunning or reference to control simulations. SO2 injection rates were proposed using a novel model predictive control regime which incorporated a second simpler climate model to forecast “optimal” decision pathways. Commencing the simulation in 2018, Arctic sea ice cover was remediated by 2043 and maintained until solar geoengineering was terminated. We found quantifying climate side effects problematic because internal climate variability hampered detection of regional climate changes beyond the Arctic. Nevertheless, through decision maker learning and the accumulation of at least 10 years time series data exploited through an annual review cycle, uncertainties in observations and forcings were successfully managed