4,680 research outputs found

    $2.00 Gas! Studying the Effects of a Gas Tax Moratorium

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    There are surprisingly few estimates of the effect of sales taxes on retail prices, especially at the firm level. Further, along both sides of a state border, a change in one state%u2019s sales tax can shed light on the nature of competition, as a subset of firms effectively experiences a change in its marginal cost. This paper considers the suspension, and subsequent reinstatement, of the 5% gasoline sales tax in Illinois and Indiana following a temporary price spike in the spring of 2000. Earlier laws set the timing of the reinstatements, providing plausibly exogenous changes in the tax rates. Using a unique dataset of daily, gas station-level data, retail gas prices are found to drop by 3% following the suspension, and increase by 4% following the reinstatements. After linking the stations to driving distance data, some evidence suggests that the tax increases are associated with higher prices up to an hour%u2019s drive into neighboring states.

    A method for determining internal noise criteria based on practical speech communication applied to helicopters

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    The relationship between the internal noise environment of helicopters and the ability of personnel to understand commands and instructions was studied. A test program was conducted to relate speech intelligibility to a standard measurement called Articulation Index. An acoustical simulator was used to provide noise environments typical of Army helicopters. Speech material (command sentences and phonetically balanced word lists) were presented at several voice levels in each helicopter environment. Recommended helicopter internal noise criteria, based on speech communication, were derived and the effectiveness of hearing protection devices were evaluated

    Evaluation of the annoyance due to helicopter rotor noise

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    A program was conducted in which 25 test subjects adjusted the levels of various helicopter rotor spectra until the combination of the harmonic noise and a broadband background noise was judged equally annoying as a higher level of the same broadband noise spectrum. The subjective measure of added harmonic noise was equated to the difference in the two levels of broadband noise. The test participants also made subjective evaluations of the rotor noise signatures which they created. The test stimuli consisted of three degrees of rotor impulsiveness, each presented at four blade passage rates. Each of these 12 harmonic sounds was combined with three broadband spectra and was adjusted to match the annoyance of three different sound pressure levels of broadband noise. Analysis of variance indicated that the important variables were level and impulsiveness. Regression analyses indicated that inclusion of crest factor improved correlation between the subjective measures and various objective or physical measures

    Users manual: Dynamics of two bodies connected by an elastic tether, six degrees of freedom forebody and five degrees of freedom decelerator

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    The equations of motion and a computer program for the dynamics of a six degree of freedom body joined to a five degree of freedom body by a quasilinear elastic tether are presented. The forebody is assumed to be a completely general rigid body with six degrees of freedom; the decelerator is also assumed to be rigid, but with only five degrees of freedom (symmetric about its longitudinal axis). The tether is represented by a spring and dashpot in parallel, where the spring constant is a function of tether elongation. Lagrange's equation is used to derive the equations of motion with the Lagrange multiplier technique used to express the constraint provided by the tether. A computer program is included which provides a time history of the dynamics of both bodies and the tension in the tether

    Computer program for the load and trajectory analysis of two DOF bodies connected by an elastic tether: Users manual

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    The derivation of the differential equations of motion of a 3 Degrees of Freedom body joined to a 3 Degrees of Freedom body by an elastic tether. The tether is represented by a spring and dashpot in parallel. A computer program which integrates the equations of motion is also described. Although the derivation of the equations of motions are for a general system, the computer program is written for defining loads in large boosters recovered by parachutes

    U.S. commercial electricity consumption

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    Commercial electricity usage exceeds that of industrial usage and is almost as large as residential electricity consumption in the United States. In this study, regional economic, demographic, and climatic data are used to analyze commercial electricity demand in the United States. Results indicate that total commercial demand for electricity is negatively related to price. In addition, the number of businesses and service income positively affect electricity demand for commercial use. The results are similar for equations estimated for kilowatt-hours demanded per business. The regional dummy variables exhibit different signs, which may occur due to climate factors because warm weather regions experience greater volumes of cooling degree-days, while cool weather regions observe larger amounts of heating degree-days. Although coefficients for the price of natural gas are positive, they do not satisfy the 5-percent significance criterion. The latter suggests that natural gas may not be a substitute good for electricity within the commercial sector of the U.S. economy.Commercial Electricity Consumption; Regional Economics

    Computer Networks, Proportionality, and Military Operations

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    Child Protection and Adult Crime: Using Investigator Assignment to Estimate Causal Effects of Foster Care

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    Nearly 20% of young prison inmates spent part of their youth in foster care - the placement of abused or neglected children with substitute families. Little is known whether foster care placement reduces or increases the likelihood of criminal behavior. This paper uses the placement frequency of child protection investigators as an instrument to identify causal effects of foster care placement on adult arrest, conviction, and imprisonment rates. A unique dataset that links child abuse investigation data to criminal justice data in Illinois allows a comparison of adult crime outcomes across individuals who were investigated for abuse or neglect as children. Families are effectively randomized to child protection investigators through a rotational assignment process, and child characteristics are similar across investigators. Nevertheless, investigator placement frequencies are predictive of subsequent foster care placement, and the results suggest that school-aged children who are on the margin of placement have lower adult arrest rates when they remain at home.
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