13,955 research outputs found
The Doctrine of Collateral Estoppel in Parole Revocation
In recent years courts have shown more recognition of the rights of parolees and probationers. Spurred by a Supreme Court decision that certain due process protections were applicable to parole revocation procedures, revocation hearings are now providing parolees and probationers some of the procedural protections available to criminal defendants at trial. Policy considerations have dictated, however, that the protections available at revocation hearings must fall far short of conferring upon the accused the full panoply of rights due a defendant at trial. As a result of the Supreme Court\u27s emphasis on the difference between revocation hearings and criminal proceedings, lower courts have held that some constitutional protections available to defendants at trial do not apply at revocation hearings. Thus, the exclusionary rule has been held inapplicable to revocation hearings. This is in contrast to a recent district court decision, Standlee v. Rhay, where it was held that because of the punitive nature of a revocation hearing, it should be treated in some respects as equivalent to a criminal proceeding. These contrasting results are not as inconsistent as they may seem at first glance, but may be harmonized, to some extent, through an analysis of the principles underlying the respective doctrines. Although revocation hearings often present both exclusionary rule and collateral estoppel problems, these are essentially distinct legal concepts
Marginal Abatement Costs and Marginal Welfare Costs for Greenhouse Gas Emissions Reductions: Results from the EPPA Model
Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/).Marginal abatement cost (MAC) curves, relationships between tons of emissions abated and the CO2 (or GHG) price, have been widely used as pedagogic devices to illustrate simple economic concepts such as the benefits of emissions trading. They have also been used to produce reduced form models to examine situations where solving the more complex model underlying the MAC is difficult. Some important issues arise in such applications: (1) are MAC relationships independent of what happens in other regions? (2) are MACs stable through time regardless of what policies have been implemented in the past?, and (3) can one approximate welfare costs from them? This paper explores the basic characteristics of MAC and marginal welfare cost (MWC) curves, deriving them using the MIT Emissions Prediction and Policy Analysis (EPPA) model. We find that, depending on the method used to construct them, MACs are affected by policies abroad. They are also dependent on policies in place in the past and depend on whether they are CO2-only or include all GHGs. Further, we find that MACs are, in general, not closely related to MWCs and therefore should not be used to derive estimates of welfare change. It would be a great convenience if a reduced-form response of a more complex model could be used to reliably conduct empirical analysis of climate change policy, but it appears that, at least as commonly constructed, MACs may be unreliable in replicating results of the parent model when used to simulate GHG policies. This is especially true if the policy simulations differ from the conditions under which the MACs were simulated. Care is needed to derive MACs under conditions closely related to the policy under consideration. In such a circumstance they may provide approximate estimates of CO2 or GHG prices for a given policy constraint. They remain a convenient way to visualize responses to a range of abatement levels.Development of the EPPA model used here is in part supported by the U.S. Department of Energy, U.S. Environmental Protection
Agency, U.S. National Science Foundation, U.S. National Aeronautics and Space Administration, U.S. National Oceanographic and Atmospheric Administration and the Industry and Foundation Sponsors of the MIT Joint Program on the Science and Policy of Global Change
CCD imaging instruments for planetary spacecraft applications
The development of new spacecraft camera systems to be used in conjunction with CCD sensors is reported. A brief overview of the science objectives and engineering constraints which influence the design of cameras for deep space is followed by a review of two current development programs, one leading to a line scan imager and the other to an area array frame camera. For each of these, a general description of the imager is given. It is evident that currently available CCDs fall short of requirements in some respects
Prospects for Plug-in Hybrid Electric Vehicles in the United States and Japan: A General Equilibrium Analysis
Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/)The plug-in hybrid electric vehicle (PHEV) may offer a potential near term, low carbon alternative to today's gasoline- and diesel-powered vehicles. A representative vehicle technology that runs on electricity in addition to conventional fuels was introduced into the MIT Emissions Prediction and Policy Analysis (EPPA) model as a perfect substitute for internal combustion engine (ICE-only) vehicles in two likely early-adopting markets, the United States and Japan. We investigate the effect of relative vehicle cost and all-electric range on the timing of PHEV market entry in the presence and absence of an advanced cellulosic biofuels technology and a strong (450ppm) economy-wide carbon constraint. Vehicle cost could be a significant barrier to PHEV entry unless fairly aggressive goals for reducing battery costs are met. If a low cost vehicle is available we find that the PHEV has the potential to reduce CO2 emissions, refined oil demand, and under a carbon policy the required CO2 price in both the United States and Japan. The emissions reduction potential of PHEV adoption depends on the carbon intensity of electric power generation and the size of the vehicle fleet. Thus, the technology is much more effective in reducing CO2 emissions if adoption occurs under an economy-wide cap and trade system that also encourages low-carbon electricity generation.BP
Conversion Research Project and the MIT Joint Program on the Science and Policy of Global
Change through a consortium of industrial sponsors and Federal grants
Barriers to the utilization of synthetic fuels for transportation
The principal types of engines for transportation uses are reviewed and the specifications for conventional fuels are compared with specifications for synthetic fuels. Synfuel processes nearing the commercialization phase are reviewed. The barriers to using synfuels can be classified into four groups: technical, such as the uncertainty that a new engine design can satisfy the desired performance criteria; environmental, such as the risk that the engine emissions cannot meet the applicable environmental standards; economic, including the cost of using a synfuel relative to conventional transportation fuels; and market, involving market penetration by offering new engines, establishing new distribution systems and/or changing user expectations
Direct measurement of the maximum tunnel rate in a radio frequency single electron transistor operated as a microwave mixer
By operating the radio frequency single electron transistor (rf-SET) as a
mixer we present measurements in which the RC roll-off of the tunnel junctions
is observed at high frequencies. Our technique makes use of the non-linear
rf-SET transconductance to mix high frequency gate signals and produce
difference-frequency components that fall within the bandwidth of the rf-SET.
At gate frequencies >15GHz the induced charge on the rf-SET island is altered
on time-scales faster than the inverse tunnel rate, preventing mixer operation.
We suggest the possibility of utilizing this technique to sense high frequency
signals beyond the usual rf-SET bandwidth.Comment: Submitted to Applied Physics Letters. Comments always very welcome,
email:[email protected] (New version contains extra data and new figs
X/X/Ka-band prime focus feed antenna for the Mars Observer beacon spacecraft
The results of an X/X/Ka-band feed design concept demonstration are presented. The purpose is to show the feasibility of adding a Ka-band beacon to the Mars Observer spacecraft. Scale model radiation patterns were made and analyzed
Biofuels, Climate Policy and the European Vehicle Fleet
Abstract and PDF report are also available on the MIT Joint Program on the Science and Policy of Global Change website (http://globalchange.mit.edu/).We examine the effect of biofuels mandates and climate policy on the European vehicle fleet, considering the prospects for diesel and gasoline vehicles. We use the MIT Emissions Prediction and Policy Analysis (EPPA) model, which is a general equilibrium model of the world economy. We expand this model by explicitly introducing current generation biofuels, by accounting for stock turnover of the vehicle fleets and by disaggregating gasoline and diesel cars. We find that biofuels mandates alone do not substantially change the share of diesel cars in the total fleet given the current structure of fuel taxes and tariffs in Europe that favors diesel vehicles. Jointly implemented changes in fiscal policy, however, can reverse the trend toward more diesel vehicles. We find that harmonizing fuel taxes reduces the welfare cost associated with renewable fuel policy and lowers the share of diesel vehicles in the total fleet to 21% by 2030 compared to 25% in 2010. We also find that eliminating tariffs on biofuel imports, which under the existing regime favor biodiesel and impede sugar ethanol imports, is welfare-enhancing and brings about further substantial reductions in CO2 emissions.This study received support from the MIT Joint Program on the Science and Policy of Global Change, which is funded by a consortium of government, industry and foundation sponsors
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