5,023 research outputs found
Diversity and Security in UK Electricity Generation: The Influence of Low Carbon Objectives
We explore the relationship between low carbon objectives and the strategic security of electricity in the context of the UK Electricity System. We consider diversity of fuel source mix to represent one dimension of security - robustness against interruptions of any one source - and apply two different diversity indices to the range of electricity system scenarios produced by the UK government and independent researchers. Using data on wind generation we also consider whether a second dimension of security - the reliability of generation availability - is compromised by intermittency of renewable generation. Our results show that low carbon objectives are uniformly associated with greater long-term diversity in UK electricity. We discuss reasons for this result, explore sensitivities, and briefly discuss possible policy instruments associated with diversity and their limitations.Diversity, Security, Low Carbon, Wind Generation, Electricity
Strengthening the EU ETS: creating a stable platform for energy sector investment
Europe faces the intertwined issues of debt, recession and economic uncertainty. These issues also impact its climate and energy policy, and in particular the EU Emissions Trading System (EU ETS). However, improvement to the EU ETS could enhance European prospects for economic stabilisation, investment and recovery. This report, Strengthening the EU ETS, analyses the underlying issues affecting the EU ETS, and sets out the main response options. The core conclusion is that no individual measure adequately addresses the combined needs: to restore confidence, to stabilise expectations, and to provide a strategic context for huge investment in the EU energy sector
Evolution of size-dependent flowering in a variable environment: partitioning the effects of fluctuating selection
In a stochastic environment, two distinct processes, namely nonlinear averaging and non-equilibrium dynamics, influence fitness. We develop methods for decomposing the effects of temporal variation in demography into contributions from nonlinear averaging and non-equilibrium dynamics. We illustrate the approach using Carlina vulgaris, a monocarpic species in which recruitment, growth and survival all vary from year to year. In Carlina the absolute effect of temporal variation on the evolutionarily stable flowering strategy is substantial (ca. 50% of the evolutionarily stable flowering size) but the net effect is much smaller (ca. 10%) because the effects of temporal variation do not influence the evolutionarily stable strategy in the same direction
Energy Efficient Service Delivery in Clouds in Compliance with the Kyoto Protocol
Cloud computing is revolutionizing the ICT landscape by providing scalable
and efficient computing resources on demand. The ICT industry - especially data
centers, are responsible for considerable amounts of CO2 emissions and will
very soon be faced with legislative restrictions, such as the Kyoto protocol,
defining caps at different organizational levels (country, industry branch
etc.) A lot has been done around energy efficient data centers, yet there is
very little work done in defining flexible models considering CO2. In this
paper we present a first attempt of modeling data centers in compliance with
the Kyoto protocol. We discuss a novel approach for trading credits for
emission reductions across data centers to comply with their constraints. CO2
caps can be integrated with Service Level Agreements and juxtaposed to other
computing commodities (e.g. computational power, storage), setting a foundation
for implementing next-generation schedulers and pricing models that support
Kyoto-compliant CO2 trading schemes
International climate finance from border carbon cost levelling
The reality of trying to raise substantial long-term revenues for international climate finance, including the outcome of the High Level Advisory Group on Climate Change Financing, is revealing the need for fresh thinking on finance sources, which takes account of political realities. Particularly after the credit crunch it will be very difficult to raise all the international finance required from sources which have clear national identity and are presently under the control of finance ministries in the OECD countries. This paper argues that the revenue associated with charging for the carbon embodied in the international trade of carbon-intensive commodities is an option with attractive properties. The paper explains this option of WTO-compatible ‘border carbon cost leveling’, indicates potential revenues from its application to key carbon-intensive commodities , and outlines the potential ethical and political economy attractions of the option
Evolution of complex flowering strategies: an age- and size-structured integral projection model
We explore the evolution of delayed age- and size-dependent flowering in the monocarpic perennial Carlina vulgaris, by extending the recently developed integral projection approach to include demographic rates that depend on size and age. The parameterized model has excellent descriptive properties both in terms of the population size and in terms of the distributions of sizes within each age class. In Carlina the probability of flowering depends on both plant size and age. We use the parameterized model to predict this relationship, using the evolutionarily stable strategy (ESS) approach. Despite accurately predicting the mean size of flowering individuals, the model predicts a step-function relationship between the probability of flowering and plant size, which has no age component. When the variance of the flowering-threshold distribution is constrained to the observed value, the ESS flowering function contains an age component, but underpredicts the mean flowering size. An analytical approximation is used to explore the effect of variation in the flowering strategy on the ESS predictions. Elasticity analysis is used to partition the agespecific contributions to the finite rate of increase (u) of the survival-growth and fecundity components of the model. We calculate the adaptive landscape that defines the ESS and generate a fitness landscape for invading phenotypes in the presence of the observed flowering strategy. The implications of these results for the patterns of genetic diversity in the flowering strategy and for testing evolutionary models are discussed. Results proving the existence of a dominant eigenvalue and its associated eigenvectors in general size- and age-dependent integral projection models are presented
Pennsylvania Constitution - Uniformity Clause - Excise Tax - Foreign and Domestic Corporations
The Pennsylvania Supreme Court has held the Excise Tax on Foreign Corporations unconstitutional since disparate tax treatment based solely on a taxpayer\u27s place of incorporation is an unreasonable classification and is therefore violative of the uniformity clause of the Pennsylvania Constitution.
Columbia Gas Transmission Corp. v. Commonwealth, 360 A.2d 592 (Pa. 1976)
Dual Enrollment and Community College Outcomes for First-Time, Full-Time Freshmen: A Quasi-Experimental Study
The purpose of this study was to explore the relationship of dual enrollment course participation by comparing first-time, full-time traditional community college students who participated in dual enrollment (N=246) to peers (N=986) that did not participate. Dual enrollment participation was defined as taking one or more dual enrollment courses. The population for this study (N=1,232) included first-time, full-time students who graduated from public high schools in the service area of Northeast State Community College over a five year span from 2008 through 2012. Propensity score matching eliminated self-selection bias by controlling for confounding covariates such as parental education, high school GPA, and ACT scores.
The major findings of the study included the following: dual enrollment participants (a) were nearly four times less likely to take remediation than non-participants, (b) earned approximately 1 extra credit hour in the first semesters of college, (c) earned higher first semester GPAs, (d) were 2.5 times more likely to graduate in 2 years (100% of degree time) and, (e) were 1.68 times more likely to graduate in 3 years (150% of degree time). The study concluded that dual enrollment benefits community college students in Tennessee, both at the beginning and completion of college. This is a significant justification for the current investment in dual enrollment by the State of Tennessee and for further increasing access to dual enrollment for all students, especially for students that live in rural areas, experience poverty, or are underrepresented in higher education
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