14,537 research outputs found

    Greening Demand: Energy Consumption and U.S. Climate Policy

    Get PDF
    The search for greener, less polluting energy supplies has dominated discussions of u.s. climate change strategy, but we often overlook cheaper and faster greenhouse gas emissions reductions achievable through energy efficiency and conservation. In this article, I outline a decade-long greening demand agenda to reduce the amount of energy consumed in the United States. The federal government should aim to reduce U.S. energy consumption by fifteen percent by 2016 and twenty percent by 2020 to achieve needed reductions in greenhouse gas emissions. While the United States has achieved notable efficiency gains since the 1970s, several market failures and other barriers continue to serve as obstacles to energy savings. These include principal-agent divergence, high implicit discount rates used in decision making on efficiency upgrades, and outmoded forms of utility regulation. I demonstrate how a greening demand agenda, centered on price signals, performance standards, informational tools, and changes in utility regulation can be used to overcome these barriers. Many of the challenges are technical and scientific, but law will play a central role in structuring incentives and shaping national markets for efficiency innovations. I conclude with some thoughts on the technical and political feasibility of greening demand

    Achieving Rapid Growth in the Transition Economies of Central Europe

    Get PDF
    This paper describes ways that the CEEs can speed their convergence with the EU by emulating the growth strategies of the very fast growing economies. In Section II, we introduce the VFGEs, and discuss some of the sources of their superior growth performance. In Section III, we demonstrate the role of key policy variables in the context of cross-country growth equations. In Section IV, we examine how the CEEs can emulate key aspects of the economic policies of the VFGEs, in order to raise their growth in the coming years.economic transition, Central Eastern Europe, economic growth

    Economic Convergence and Economic Policies

    Get PDF
    Many of the crucial debates in development economics are encapsulated in the question of economic convergence. Is there a tendency for the poorer countries to grow more rapidly than the richer countries, and thereby to converge in living standards? Or instead, are there tendencies for the "rich to get richer, and the poor to get poorer," so that the gap between rich and poor nations tends to widen over time?economic convergence, economic policy

    Classical Stability of the BTZ Black Hole in Topologically Massive Gravity

    Full text link
    We demonstrate the classical stability of the BTZ black hole within the context of topologically massive gravity. The linearized perturbation equations can be solved exactly in this case. By choosing standard boundary conditions appropriate to the stability problem, we demonstrate the absence of modes which grow in time, for all values of the Chern-Simons coupling.Comment: 11 page

    Natural Resource Abundance and Economic Growth

    Get PDF
    One of the surprising features of modern economic growth is that economies with abundant natural resources have tended to grow less rapidly than natural-resource-scarce economies. In this paper we show that economies with a high ratio of natural resource exports to GDP in 1971 (the base year) tended to have low growth rates during the subsequent period 1971-89. This negative relationship holds true even after controlling for variables found to be important for economic growth, such as initial per capita income, trade policy, government efficiency, investment rates, and other variables. We explore the possible pathways for this negative relationship by studying the cross-country effects of resource endowments on trade policy, bureaucratic efficiency, and other determinants of growth. We also provide a simple theoretical model of endogenous growth that might help to explain the observed negative relationship.

    Economic Convergence and Economic Policies

    Get PDF
    Many of the crucial debates in development economics are encapsulated in the question of economic convergence. Is there a tendency for the poorer countries to grow more rapidly than the richer countries, and thereby to converge in living standards? Some recent research on endogenous growth has emphasized increasing returns as a possible reason not to expect convergence. Other research has suggested that convergence may be achieved only after poor countries attain a threshold level of income or human capital. This paper presents evidence that a sufficient condition for higher-than-average growth of poorer countries, and therefore convergence, is that poorer countries follow reasonably efficient economic policies, mainly open trade and protection of private property rights.

    Improvements in the reconstruction of time-varying gene regulatory networks: dynamic programming and regularization by information sharing among genes

    Get PDF
    <b>Method:</b> Dynamic Bayesian networks (DBNs) have been applied widely to reconstruct the structure of regulatory processes from time series data, and they have established themselves as a standard modelling tool in computational systems biology. The conventional approach is based on the assumption of a homogeneous Markov chain, and many recent research efforts have focused on relaxing this restriction. An approach that enjoys particular popularity is based on a combination of a DBN with a multiple changepoint process, and the application of a Bayesian inference scheme via reversible jump Markov chain Monte Carlo (RJMCMC). In the present article, we expand this approach in two ways. First, we show that a dynamic programming scheme allows the changepoints to be sampled from the correct conditional distribution, which results in improved convergence over RJMCMC. Second, we introduce a novel Bayesian clustering and information sharing scheme among nodes, which provides a mechanism for automatic model complexity tuning. <b>Results:</b> We evaluate the dynamic programming scheme on expression time series for Arabidopsis thaliana genes involved in circadian regulation. In a simulation study we demonstrate that the regularization scheme improves the network reconstruction accuracy over that obtained with recently proposed inhomogeneous DBNs. For gene expression profiles from a synthetically designed Saccharomyces cerevisiae strain under switching carbon metabolism we show that the combination of both: dynamic programming and regularization yields an inference procedure that outperforms two alternative established network reconstruction methods from the biology literature

    CP Violation and Arrows of Time Evolution of a Neutral KK or BB Meson from an Incoherent to a Coherent State

    Full text link
    We study the evolution of a neutral KK meson prepared as an incoherent equal mixture of K0K^0 and K0ˉ\bar{K^0}. Denoting the density matrix by \rho(t) = {1/2} N(t) [\1 + \vec{\zeta}(t) \cdot \vec{\sigma} ] , the norm of the state N(t)N(t) is found to decrease monotonically from one to zero, while the magnitude of the Stokes vector ζ(t)|\vec{\zeta}(t)| increases monotonically from zero to one. This property qualifies these observables as arrows of time. Requiring monotonic behaviour of N(t)N(t) for arbitrary values of γL,γS\gamma_L, \gamma_S and Δm\Delta m yields a bound on the CP-violating overlap δ=KLKS\delta = \braket{K_L}{K_S}, which is similar to, but weaker than, the known unitarity bound. A similar requirement on ζ(t)|\vec{\zeta}(t)| yields a new bound, δ2<1/2(ΔγΔm)sinh(3π4ΔγΔm)\delta^2 < {1/2} (\frac{\Delta \gamma}{\Delta m}) \sinh (\frac{3\pi}{4} \frac{\Delta \gamma}{\Delta m}) which is particularly effective in limiting the CP-violating overlap in the B0B^0-B0ˉ\bar{B^0} system. We obtain the Stokes parameter ζ3(t)\zeta_3(t) which shows how the average strangeness of the beam evolves from zero to δ\delta. The evolution of the Stokes vector from ζ=0|\vec{\zeta}| = 0 to ζ=1|\vec{\zeta}| = 1 has a resemblance to an order parameter of a system undergoing spontaneous symmetry breaking.Comment: 13 pages, 6 figures. Inserted conon "." in title; minor change in text. To appear in Physical review
    corecore