3,663 research outputs found

    Emissions Trading with Profit-Neutral Permit Allocations

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    This paper examines the operation of an emissions trading scheme (ETS) in a Cournot oligopoly. We study the impact of the ETS on industry output, price, costs, emissions, and profits. In particular, we develop formulae for the number of emissions permits that have to be freely allocated to firms in order to neutralize any adverse impact the ETS may have on profits. These formulae tell us that the profit impact of the ETS is usually limited. Indeed, under quite general conditions, industry profits are preserved so long as firms are freely allocated a fraction of their total demand for permits, with this fraction being lower than the industry's Herfindahl index.Emissions trading, permit allocation, profit-neutrality, cost pass-through, abatement, grandfathering

    Obtaining Self-similar Scalings in Focusing Flows

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    The surface structure of converging thin fluid films displays self-similar behavior, as was shown in the work by Diez et al [Q. Appl. Math 210, 155, 1990]. Extracting the related similarity scaling exponents from either numerical or experimental data is non-trivial. Here we provide two such methods. We apply them to experimental and numerical data on converging fluid films driven by both surface tension and gravitational forcing. In the limit of pure gravitational driving, we recover Diez' semi-analytic result, but our methods also allow us to explore the entire regime of mixed capillary and gravitational driving, up to entirely surface tension driven flows. We find scaling forms of smoothly varying exponents up to surprisingly small Bond numbers. Our experimental results are in reasonable agreement with our numerical simulations, which confirm theoretically obtained relations between the scaling exponents.Comment: 11 pages, 11 figures, accepted for Phys Rev

    Translocation of reindeer from South Georgia to the Falkland Islands

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    This report describes the first translocation of reindeer Rangifer tarandus from South Georgia to the Falkland Islands, in the South Atlantic Ocean. Reindeer were introduced from Norway to the subantarctic island of South Georgia on three occasions in the early 1900s by Norwegian whalers, and today they exist as two discrete herds, numbering approximately 2600 individuals in total. Because of concerns over the impact on native vegetation, the long-term eradication of reindeer from South Georgia has recently been proposed. A translocation of reindeer to the Falkland Islands was undertaken in 2001 by the Falkland Island Government with two objectives: (1) to preserve the genetic resources of at least one of the South Georgia herds; and (2) to facilitate the diversification of the agricultural sector of the Falkland Islands by establishing a commercial reindeer herd. Techniques developed and used in North America for the successful relocation of large numbers of calves were adopted for the translocation. A total of 59 calves (26 females and 33 males) were successfully translocated from South Georgia to the Falklands Islands in 2001, and subsequently produced their first offspring in 2003. Good husbandry practices and an understanding of biology and behaviour are essential for the successful translocation of reindeer.Flytting av rein fra Sør-Georgia til FalklandsøyeneAbstract in Norwegian / Sammendrag: Artikkelen beskriver den første overføring av rein Rangifer tarandus fra Sør-Georgia til Falklandsøyene i søratlanteren. Tamrein fra Norge ble flyttet til den subarktiske øya Sør-Georgia ved tre anledninger i perioden 1911 til 1925 i forbindelse med den norske hvalfangsten der. I dag består bestanden av rundt regnet 2600 dyr fordelt på to geografisk atskilte flokker. Av hensyn til den naturlige vegetasjonen på øya er det forslag om å på sikt utrydde reinbestanden på øya. Regjeringen på Falklandsøyene foretok en første overføring av rein fra Sør-Georgia i 2001 ut fra en målsetting om å 1) bevare genetiske ressurser fra minst en av de to reinflokkene, og 2) øke mulighetene innenfor landbrukssektoren på Falklandsøyene ved å etablere en kommersiell reinflokk der. Overføringen ble utført med metoder som hadde vist seg formålstjenlige ved flytting og nylokalisering av kalver i Nord-Amerika. Totalt ble 59 kalver overført i 2001 derav 26 hunndyr. De overførte reinene produserte kalver i 2003. God driftspraksis og biologisk og atferdsmessig forståelse var viktig for en vellykket overføring

    Influence of the rod photoresponse on light adaptation and circadian rhythmicity in the cone ERG

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    Purpose: In the mammalian retina, rod and cone pathways are fundamentally intertwined, with signals from both converging on cone bipolar cells to reach retinal ganglion cells. Psychophysical and electrophysiological data suggests that, as a consequence, rod signal transduction has a suppressive effect on the activity of cone pathways. It therefore might be assumed that the balance between rod and cone input to cone bipolar cells would be subject to dynamic regulation. There is evidence of light and time-of-day dependent alterations in this parameter. Here we set out to determine the extent to which such changes in rod-cone pathway convergence explain alterations in cone pathway function associated with light adaptation and circadian phase by recording cone electroretinograms (ERGs) in mice deficient in rod phototransduction. Methods: Cone-isolated ERGs elicited by bright flashes superimposed on a rod saturating background light were recorded from wild-type and rod transducin deficient (Gnat1−/−) mice. The process of light adaptation was observed by tracing changes in the ERG waveform over 20 min exposure to the background light in these genotypes, and circadian control by comparing responses at subjective midday and midnight. Results: The cone ERG b-wave exhibited significantly enhanced amplitude and reduced latency (implicit time) in Gnat1−/− mice under all conditions. Light adaptation was associated with a robust increase in b-wave amplitude in Gnat1−/− mice but, in contrast to wild types, almost no change in implicit time. Gnat1−/− mice retained circadian rhythms in the cone ERG with b-wave amplitudes larger and latencies reduced during the subjective day. Conclusions: Rod phototransduction has a strong suppressive effect on the cone ERG. Light adaptation in cone pathways relies in part on reductions in this effect, although mechanisms intrinsic to cone pathways also play an important role. Similarly, while changes in coupling between rod and cone pathways over the course of the day may contribute to circadian regulation of the cone pathway they are not sufficient to explain circadian rhythms in the wild-type cone ERG

    Reengineering DoD through enterprise-wide migration to open systems

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    The Department of Defense cannot afford to develop and deploy information systems that have no growth potential. Legacy systems must be replaced with flexible, highly interoperable systems that produce high residual values. With shrinking budgets, depreciation of existing hardware, and rising maintenance of legacy systems, organizations must deploy systems that are capable of evolving with changing business requirements. The Department of Defense enterprise vision for information management (IM) emphasizes integration, interoperability, flexibility, and efficiency through the development of a common, multipurpose, standards-based technical infrastructure. This vision requires a new paradigm for building information systems. The new paradigm relies on open systems, which make it easier, less expensive, and faster to develop and change applications and to employ new technology features. This research examines open systems and provides a strategy for organizations to migrate to them. A case study of the Naval Postgraduate School illustrates the strategy. Provisionally, a prototype application models the desired characteristics of an open system.http://archive.org/details/reengineeringdod1094532221NAU.S. Navy (USN) authorU.S. Army (USA) authorApproved for public release; distribution is unlimited

    Assessing the Risk of 100-year Freshwater Floods in the Lamprey River Watershed of New Hampshire Resulting from Changes in Climate and Land Use

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    What is the coastal resource issue the project sought to address? Both the magnitude and frequency of freshwater flooding is on the rise in seacoast NH and around much of New England. In the Great Bay watershed, this is the result of two primary causes: 1) increases in impervious surface stemming from a three-to-four fold increase in developed land since 1962; and 2) changing rainfall patterns in part exemplified by a doubling in the frequency of extreme weather events that drop more than 4 inches of precipitation in less than 48 hours (Wake et al., 2011) over the same time period. Moreover, the size of the 100-year precipitation event in this region has increased 26% from 6.3 inches to 8.5 inches from the mid 1950’s to 2010 (NRCC and NRCS, 2012). One consequence is the occurrence of three 100-year floods measured on the Lamprey River at Packers Falls since 1987, and a fourth if the three days of flooding in March of 2010 had occurred instead in two days (Figure 1). Flooding events are expected to continue to increase in magnitude and frequency as land in the watershed is further developed and climate continues to change in response to anthropogenic forcing (e.g., Hayhoe et el., 2007; IPCC, 2007; Karl et al., 2009). Land use management strategies, in particular low impact development (LID) zoning requirements, are one strategy that communities can employ for increased resiliency to flooding with the greatest influence in urban environments
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