4,016 research outputs found
Climate cost uncertainty, retrofit cost uncertainty, and infrastructure closedown : a framework for analysis
Large and energy-intensive infrastructure investments with long life times have substantial implications for climate policy. This study focuses on options to scale down energy consumption and carbon emissions now and in the future, and on the costs of doing so. Two ways carbon emissions can be reduced post-investment include retrofitting the infrastructure, or closing it down. Generally, the presence of bulky infrastructure investments makes it more costly to reduce emissions later. Moreover, when expected energy and environmental costs are continually rising, inherent biases in the selection processes for infrastructure investments lead to excessive energy intensity in such investments. Thus great care must be taken when choosing the energy intensity of the infrastructure at the time of investment. Simulations indicate that optimally exercising the retrofit option, when it is available, reduces ex ante expected energy consumption relative to the no-option case. Total energy plus retrofit costs can also be substantially reduced, the more so the larger is ex ante cost uncertainty. However, the availability of the retrofit option also leads to a more energy intensive initial infrastructure choice; this offsets some, but usually not all, of the gains from options for subsequent retrofitting.Energy Production and Transportation,Transport Economics Policy&Planning,Climate Change Mitigation and Green House Gases,Climate Change Economics,Environment and Energy Efficiency
Infrastructure investments under uncertainty with the possibility of retrofit : theory and simulations
Investments in large, long-lived, energy-intensive infrastructure investments using fossil fuels increase longer-term energy use and greenhouse gas emissions, unless the plant is shut down early or undergoes costly retrofit later. These investments will depend on expectations of retrofit costs and future energy costs, including energy cost increases from tighter controls on carbon emissions. Simulation analysis shows that the retrofit option can significantly reduce anticipated future energy consumption as of the time of initial investment, and total future energy plus retrofit costs. The more uncertain are the costs, the greater the value of this option. However, the future retrofit option also induces more energy-intensive infrastructure choices, partly offsetting the direct effect of having the option on anticipated energy use. Efficient, forward-looking infrastructure investments have high potential for reducing long-term energy consumption. Particularly if energy prices are expected to rise, however, the potential for reduced energy consumption will be eroded if expectations of energy prices do not include environmental costs or future retrofit possibilities and technologies are not adequately developed.Energy Production and Transportation,Climate Change Economics,Climate Change Mitigation and Green House Gases,Environment and Energy Efficiency,Energy and Environment
Optimal climate change adaptation and mitigation expenditures in environmentally small economies
We study the optimal role of mitigation and adaptation strategies for environmentally small economies, that is, economies that are witnessing an exogenous increase in emissions to which they are contributing very little. Our results lead to three main conclusions. First, small economies should concentrate their environmental efforts, if any, on adaptation. This is a recommendation based on cost effectiveness rather than on any idea about these economies indulging in free riding. Second, environmentally small economies that are unable to spend enough on adaptation may end up spending less on mitigation in the long term, owing to their impoverishment as a result of negative climate shocks. Third, higher mitigation expenditures may arise not only as a result of greater optimal adaptation expenditures, but also because of increased adaptation to the incentives for mitigation provided by richer countries. For the simulations, we use a calibrated optimal growth model for Brazil, Chile, and the United States. JEL classifications: Q52, Q5
THREE ESSAYS IN POLITICAL ECONOMY
This dissertation explores three different relevant questions in political economy. Chapter 1 is devoted to understanding why populist-outsider candidates get elected, and what conditions may favor/hinder their electability. The results show that countries with a higher income and wealth concentration are more likely to elect populist outsiders than countries where income and wealth are more equally distributed. It is also shown that elections with a runoff also are less likely to bring these populist outsiders into office.
Chapter 2 in turn explores the role of the middle class in moderating political outcome in a framework where money and votes play two distinctive roles in the election process. In this chapter, a three-class model of heterogeneous agents is developed in which groups affect policy outcomes through their voting behavior and contributions to political campaigns, and where income inequality can lead to extreme policy outcomes. Increasing the size of the middle class reduces the likelihood of extreme policy outcomes, as does a richer middle class. This result highlights the importance of a large and strong middle class for political stability.
Finally Chapter 3 looks at the question of why inequality has remained persistently high in Chile despite its success in reducing poverty and achieving high growth for two decades while having a mostly pro-poor structure of public expenditures. We show that the key factors explaining this persistent inequality have been a low level of fiscal expenditures caused by low tax revenues that have not permitted enough public investment in human capital and R&D
Analytical Gradients for Projection-Based Wavefunction-in-DFT Embedding
Projection-based embedding provides a simple, robust, and accurate approach
for describing a small part of a chemical system at the level of a correlated
wavefunction method while the remainder of the system is described at the level
of density functional theory. Here, we present the derivation, implementation,
and numerical demonstration of analytical nuclear gradients for
projection-based wavefunction-in-density functional theory (WF-in-DFT)
embedding. The gradients are formulated in the Lagrangian framework to enforce
orthogonality, localization, and Brillouin constraints on the molecular
orbitals. An important aspect of the gradient theory is that WF contributions
to the total WF-in-DFT gradient can be simply evaluated using existing WF
gradient implementations without modification. Another simplifying aspect is
that Kohn-Sham (KS) DFT contributions to the projection-based embedding
gradient do not require knowledge of the WF calculation beyond the relaxed WF
density. Projection-based WF-in-DFT embedding gradients are thus easily
generalized to any combination of WF and KS-DFT methods. We provide numerical
demonstration of the method for several applications, including calculation of
a minimum energy pathway for a hydride transfer in a cobalt-based molecular
catalyst using the nudged-elastic-band method at the CCSD-in-DFT level of
theory, which reveals large differences from the transition state geometry
predicted using DFT.Comment: 15 pages, 4 figure
New valid inequalities and facets for the simple plant location problem
The Simple Plant Location Problem is a well-known (and NP-hard) combinatorial optimisation problem, with applications in logistics. We present a new family of valid inequalities for the associated family of polyhedra, and show that it contains an exponentially large number of new facet-defining members. We also present a new procedure, called facility augmentation, which enables one to derive even more valid and facet-defining inequalities
Attending to Eliza: Rapid brain responses reflect competence attribution in virtual social feedback processing
Schindler S, Miller GA, KiĂźler J. Attending to Eliza: Rapid brain responses reflect competence attribution in virtual social feedback processing. Social Cognitive and Affective Neuroscience. 2019;14(10):1073-1086.In the age of virtual communication, the source of a message is often inferred rather than perceived, raising the question of how sender attributions affect content processing. We investigated this issue in an evaluative feedback scenario. Participants were told that an expert psychotherapist, a layperson or a randomly acting computer was going to give them online positive, neutral or negative personality feedback while high-density EEG was recorded. Sender attribution affected processing rapidly, even though the feedback was on average identical. Event-related potentials revealed a linear increase with attributed expertise beginning 150 ms after disclosure and most pronounced for N1, P2 and early posterior negativity components. P3 and late positive potential amplitudes were increased for both human senders and for emotionally significant (positive or negative) feedback. Strikingly, feedback from a putative expert prompted large P3 responses, even for inherently neutral content. Source analysis localized early enhancements due to attributed sender expertise in frontal and somatosensory regions and later responses in the posterior cingulate and extended visual and parietal areas, supporting involvement of mentalizing, embodied processing and socially motivated attention. These findings reveal how attributed sender expertise rapidly alters feedback processing in virtual interaction and have implications for virtual therapy and online communication.how attributed sender expertise rapidly alters feedback processing in virtual interaction and have implications for virtual therapy and on-line communication.</jats:p
On the Developer Adoption of Scrum: A New Acceptance Model for Agile Methodologies
In recent years, the agile Scrum methodology has become a popular software development approach. It significantly differs from traditional approaches as it promotes communication, self-organization, flexibility, and innovation instead of extensive planning and codified processes. While such a paradigm shift promises to better support the timely delivery of high-quality software in turbulent business environments, its success considerably depends on the willingness of developers to adopt the agile methodology. In this paper, we present a framework with drivers and inhibitors to the developer acceptance of Scrum. It combines analytical with empirical findings and can be used as a theoretical basis to empirically evaluate the actual support of Scrum in concrete scenarios. The introduced framework is based on the extended Technology Acceptance Model (TAM), which has been proven to be also applicable to describe the intention of developers to use a methodology. Building upon results from qualitative in-depth interviews with six experienced Scrum experts of a German DAX-30 company, we refine the general determinants of adoption contained in the TAM with several observed factors that influence the willingness of developers to use Scrum in practice
A survey of thickened fluid prescribing and monitoring practices of Australian health professionals.
"This is the peer reviewed version of the following article: [Murray, J., Miller, M., Doeltgen, S. & Scholten, I. (2014). A survey of thickened fluid prescribing and monitoring practices of Australian health professionals. Journal of Evaluation in Clinical Practice, 20(5), 596-600.], which has been published in final form at [http://dx.doi.org/10.1111/jep.12154]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. http://olabout.wiley.com/WileyCDA/Section/id-820227.html#terms"RATIONALE, AIMS AND OBJECTIVES:
This study aimed to describe (1) how thickened fluids are supplied to clients with dysphagia; (2) how clients' consumption of thickened fluids and hydration status is monitored; and (3) the impact of institutional factors on thickened fluid intake and hydration in Australian health care settings.
METHODS:
Speech pathologists, dietitians and nurses working in Australian health care settings were asked to voluntarily participate in an online survey that was advertised through their respective professional associations. The questions required a self-report of their practice with respect to thickened fluids.
RESULTS:
Few health care facilities (17%) monitored thickened fluid consumption routinely even though, in the opinion of 51% the respondents, clients on thickened fluids at their facility do not drink enough. Palatability of the thickened fluid products and patients' dependence on others for drinking were thought to have a major impact on fluid intake. Respondents also highlighted institutional factors such as inadequate assistance from staff and inconsistent systems for monitoring fluid intake and signs of dehydration. The most common way to address inadequate intake was for nurses to 'push fluids' (87%). Free water protocols were used only 14% of the time and setting small oral fluid targets throughout the day was the least common strategy (11%).
CONCLUSIONS:
There is a need for Australian health care facilities to educate all clinical staff about the risks of dehydration and develop clinical pathways for clients with dysphagia, which include routine monitoring of oral fluid consumption and dehydration and timely intervention
- …