Toward a sustainable global energy supply infrastructure : net energy balance and density considerations

This paper complements previous work on the economics of different energy resources by examining the growth potential of alternative electricity supply infrastructures as constrained by innate physical limits. Coal-fired generation meets the criteria of longevity (abundance of energy source) and scalability (effective capability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but it carries a very heavy carbon footprint. Renewables and nuclear power meet both the longevity and climate friendliness criteria. However, they vary in terms of their ability to deliver net energy at a scale needed for meeting a huge global energy demand. The low density of renewable resources for electricity generation and the current intermittency of many renewables limit their ability to achieve high rates of growth. And a significant global increase in nuclear power deployment could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. The transition to a low carbon economy is likely to prove much more challenging than some optimists have claimed.Energy Production and Transportation,Climate Change Mitigation and Green House Gases,Energy and Environment,Environment and Energy Efficiency,Energy Demand

Towards a Sustainable Global Energy Supply Infrastructure: Net Energy Balance and Density Considerations

This paper employs a framework of dynamic energy analysis to model the growth potential of alternative electricity supply infrastructures as constrained by innate physical energy balance and dynamic response limits. Coal- red generation meets the criteria of longevity (abundance of energy source) and scalability (ability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but carries a very heavy carbon footprint. Renewables and nuclear power, on the other hand, meet both the longevity and environmental friendliness criteria. However, due to their substantially di¤erent energy densities and load factors, they vary in terms of their ability to deliver net excess energy and attain the scale needed for meeting the huge global energy demand. The low power density of renewable energy extraction and the intermittency of renewable ows limit their ability to achieve high rates of indigenous infrastructure growth. A signi cant global nuclear power deployment, on the other hand, could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. Thus, the transition to a low carbon economy is likely to prove much more challenging than early optimists have claimed.dynamic energy analysis; alternative electricity supply; coal; nuclear energy

Maltreated children in the Looked After System: a comparison of outcomes for those who go home and those who do not

This project focuses on the consequences of decisions to reunify children who had entered the looked-after system for abuse or neglect. It compares the progress and outcomes of a sample of maltreated children who either went home or remained in the looked-after system

The Law of the Minimum and Sources of Nonzero Skewness for Crop Yield Distributions

Crop yields are not commonly found to be normally distributed, but the cause of the non-normal distribution is unclear. The non-normality might be due to weather variables and/or an underlying von Liebig law of the minimum (LoM) production function. Our objective is to determine the degree to which an underlying linear response stochastic plateau production function can explain the skewness of Oklahoma wheat yields at varied nitrogen rates. We use farm-level wheat data from a long-term experiment in Oklahoma, which is a unique data set to the literature. The Tembo et al. (2008) production function provides negative skewness at all levels of nitrogen with skewness near zero for both very high and very low levels of nitrogen. Observed skewness for wheat yields, however, is positive. The variation in the plateau by year shows positive skewness. Skewness in yield potential related to weather should be considered as a possible explanation of skewness.linear plateau model, non-normal distributions, skewness, wheat, yield distribution, Production Economics, Risk and Uncertainty, Q10,

Anchoring effects in the development of false childhood memories

When people receive descriptions or doctored photos of events that never happened, they often come to remember those events. But if people receive both a description and a doctored photo, does the order in which they receive the information matter? We asked people to consider a description and a doctored photograph of a childhood hot air balloon ride, and we varied which medium they saw first. People who saw a description first reported more false images and memories than people who saw a photo first, a result that fits with an anchoring account of false childhood memories

The Face Of Feedback: Exploring The Use Of Asynchronous Video To Deliver Instructor Feedback In Multidisciplinary Online Courses

ABSTRACT THE FACE OF FEEDBACK: EXPLORING THE USE OF ASYNCHRONOUS VIDEO TO DELIVER INSTRUCTOR FEEDBACK IN MULTIDISCIPLINARY ONLINE COURSES by NAIMAH NOELLE WADE November 2015 Advisor: Dr. Monica Tracey Major: Instructional Technology Degree: Doctor of Philosophy The purpose of this qualitative, design-based research study was to design, implement, and explore the use of an asynchronous video feedback protocol in higher education online courses. Bannan’s (2013) Integrative Learning Design Framework guided the design and implementation strategy for this study by dictating its three core phases; 1) Informed Exploration, 2) Enactment, and 3) Local Impact Evaluation. The video feedback intervention cycled through two design iterations to understand the experiences of the study participants and interpret the corresponding implications for instructional designers, teaching and learning practitioners and student success administrators. The study gathered data using multiple methods including, a designer reflection journal, a practitioners pre-launch assessments, weekly reflections questionnaires, post-intervention debrief interviews and student reflections. To expand upon the existing body of research on technology-enhanced feedback provision in online courses, this study explored video feedback from the perspective of faculty members and instructors, with specific regard their perceptions and engagement with the selected video technology. The findings revealed that an asynchronous video feedback protocol, designed to integrate Screen-cast-o-matic and Blackboard, captured a plausible solution to an authentic problem with instructor feedback. Using grounded theory, the findings were unpacked as they relate to student/instructor experiences and perceived learning gains. The study also drew upon its evidenced-based conclusions to summarize a recommended set of design principles that emerged in the research process. The first principle related to the design process, as a whole; The design process for an asynchronous feedback protocol is dynamic and revolves around a clear picture of the desired end, coupled with and systemic approach to progressing from concept to creation of a functional product. The second principle was associated with design decisions; The instinctive decision-making of the designer plays a defining role in bridging the gap between the intervention’s technical needs and the stakeholder’s functional desires. The third principle related to the universal application of asynchronous video feedback; With deliberate effort, asynchronous video feedback can be designed transcend specific topics or subject matters. The fourth principle addressed integrating asynchronous video feedback; The expectations of asynchronous video feedback users should be managed such that self-efficacy is cultivated prior to implementation. This study revealed implications for several stakeholders in higher education including instructional designers, course developers, faculty, student success administrators and teaching and learning practitioners. For instructional designers and course developers, the most striking implications of this study relate to the role of failure in design and the emergent design principles for an asynchronous video feedback intervention. For administrators in teaching and learning roles or those who work on student success, this study presents an innovative approach to narrowing the psychological distance that can characterizes technology mediated learning environments. It also positions video feedback as a potential strategy for streamlining the feedback provision practices of academic faculty. Finally, it sheds light on the importance of instructor visibility in the online environment and the impact that a more tangible connection with the instructor could have on student engagement