12,346 research outputs found
THE CONSTITUTIONALITY OF TAKING A SPORTS FRANCHISE BY EMINENT DOMAIN AND THE NEED FOR FEDERAL LEGISLATION TO RESTRICT FRANCHISE RELOCATION
In 1985, two cities were in proceedings to each take over a sports franchises located within their respective cities. However, a number of constitutional limitations may prevent a city from taking sports franchises. This Note examines the constitutional public use, just compensation,right to travel and commerce clause limitations as applied to the taking of sports franchises by eminent domain. This Note concludes that eminent domain is an improper method of protecting cities\u27 interests in preventing the relocation of sports franchises. Consequently, it suggests that only carefully drawn federal legislation can protect a city\u27s interest in keeping its sports franchises without subjecting franchises to nonuniform and discriminatory treatment
Operating limits for acoustic measurement of rolling bearing oil film thickness
An ultrasonic pulse striking a thin layer of liquid trapped between solid bodies will be partially reflected. The proportion reflected is a function of the layer stiffness, which in turn depends on the film thickness and its bulk modulus. In this work, measurements of reflection have been used to determine the thickness of oil films in elastohydrodynamic lubricated (EHL) contacts. A very thin liquid layer behaves like a spring when struck by an ultrasonic pulse. A simple quasi-static spring model can be used to determine the proportion of the ultrasonic waves reflected. Experiments have been performed on a model EHL contact between a ball and a flat surface. A transducer is mounted above the contact such that the ultrasonic wave is focused onto the oil film. The reflected signals are captured and passed to a PC for processing. Fourier analysis gives the reflection spectrum that is then used to determine the stiffness of the liquid layer and hence its thickness. In further testing, an ultrasonic transducer has been mounted in the housing of a deep-groove ball bearing to measure the film generated at the outer raceway as each ball passes. Results from both the ball-flat and ball bearing measurements agree well with steady-state theoretical EHL predictions. The limits of the measuring technique, in terms of the measurable rolling bearing size and operating parameters, have been investigated
Decoherence of spin echoes
We define a quantity, the so-called purity fidelity, which measures the rate
of dynamical irreversibility due to decoherence, observed e.g in echo
experiments, in the presence of an arbitrary small perturbation of the total
(system + environment) Hamiltonian. We derive a linear response formula for the
purity fidelity in terms of integrated time correlation functions of the
perturbation. Our relation predicts, similarly to the case of fidelity decay,
faster decay of purity fidelity the slower decay of time correlations is. In
particular, we find exponential decay in quantum mixing regime and faster,
initially quadratic and later typically gaussian decay in the regime of
non-ergodic, e.g. integrable quantum dynamics. We illustrate our approach by an
analytical calculation and numerical experiments in the Ising spin 1/2 chain
kicked with tilted homogeneous magnetic field where part of the chain is
interpreted as a system under observation and part as an environment.Comment: 22 pages, 10 figure
Land Use and Mapping
Land use management, classification, and mapping based on ERTS-1 observations - Conferenc
The fate of NOx emissions due to nocturnal oxidation at high latitudes: 1-D simulations and sensitivity experiments
The fate of nitrogen oxide pollution during high-latitude winter is controlled by reactions of dinitrogen pentoxide (N2O5) and is highly affected by the competition between heterogeneous atmospheric reactions and deposition to the snowpack. MISTRA (MIcrophysical STRAtus), a 1-D photochemical model, simulated an urban pollution plume from Fairbanks, Alaska to investigate this competition of N2O5 reactions and explore sensitivity to model parameters. It was found that dry deposition of N2O5 made up a significant fraction of N2O5 loss near the snowpack, but reactions on aerosol particles dominated loss of N2O5 over the integrated atmospheric column. Sensitivity experiments found the fate of NOx emissions were most sensitive to NO emission flux, photolysis rates, and ambient temperature. The results indicate a strong sensitivity to urban area density, season and clouds, and temperature, implying a strong sensitivity of the results to urban planning and climate change. Results suggest that secondary formation of particulate (PM2.5) nitrate in the Fairbanks downtown area does not contribute significant mass to the total PM2.5 concentration, but appreciable amounts are formed downwind of downtown due to nocturnal NOx oxidation and subsequent reaction with ammonia on aerosol particles
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Banning open carry of unloaded handguns decreases firearm-related fatalities and hospital utilization.
BackgroundSince 1967, in California it has been illegal to openly carry a loaded firearm in public except when engaged in hunting or law enforcement. However, beginning January 1, 2012, public open carry of unloaded handguns also became illegal. Fatal and non-fatal (NF) firearm injuries were examined before and after adoption of the 2012 ban to quantify the effect of the new law on public health.MethodsState-level data were obtained directly from California and nine other US state inpatient and emergency department (ED) discharge databases, and the Centers for Disease Control Web-Based Injury Statistics Query and Reporting System. Case numbers of firearm fatalities, NF hospitalizations, NF ED visits, and state-level population estimates were extracted. Each incident was classified as unintentional, self-inflicted, or assault. Crude incidence rates were calculated. The strength of gun laws was quantified using the Brady grade. There were no changes to open carry in these nine states during the study. Using a difference-in-difference technique, the rate trends 3 years preban and postban were compared.ResultsThe 2012 open carry ban resulted in a significantly lower incident rate of both firearm-related fatalities and NF hospitalizations (p<0.001). The effect of the law remained significant when controlling for baseline state gun laws (p<0.001). Firearm incident rate drops in California were significant for male homicide (p=0.023), hospitalization for NF assault (p=0.021  male; p=0.025 female), and ED NF assault visits (p=0.04). No significant decreases were observed by sex for suicides or unintentional injury. Changing the law saved an estimated 337 lives (3.6% fewer deaths) and 1285 NF visits in California during the postban period.DiscussionOpen carry ban decreases fatalities and healthcare utilization even in a state with baseline strict gun laws. The most significant impact is from decreasing firearm-related fatal and NF assaults.Level of evidenceIII, epidemiology
Period-Luminosity Relation for Type II Cepheids
We have estimated JHKs magnitudes corrected to mean intensity for LMC type II
Cepheids found in the OGLE-III survey. Period-luminosity relations (PLRs) are
derived in JHKs as well as in a reddening-free VI parameter. The BL Her stars
(P<4d) and the W Vir stars (P=4 to 20d) are co-linear in these PLRs. The slopes
of the infrared relations agree with those found previously for type II
Cepheids in globular clusters within the uncertainties. Using the pulsation
parallaxes of V553 Cen and SW Tau, the data lead to an LMC modulus of
18.46+-0.10 mag, uncorrected for any metallicity effects. We have now
established the PLR of type II Cepheids as a distance indicator by confirming
that (almost) the same PLR satisfies the distributions in the PL diagram of
type II Cepheids in (at least) two different systems, i.e. the LMC and Galactic
globular clusters, and by calibrating the zero point of the PLR. RV Tau stars
in the LMC, as a group, are not co-linear with the shorter-period type II
Cepheids in the infrared PLRs in marked contrast to such stars in globular
clusters. We note differences in period distribution and infrared colors for RV
Tau stars in the LMC, globular clusters and Galactic field. We also compare the
PLR of type II Cepheids with that of classical Cepheids.Comment: To appear in the proceedings for the conference "Stellar Pulsation:
Challenges for Theory and Observations" held in Santa Fe, US
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