125,492 research outputs found
The Prometheus Challenge Redux
Following up on its predecessor in this Journal, the article defends philosophy as a guide to making and analyzing art; identifies Cubist solutions to the Prometheus Challenge, including a novel analysis of Picassoâs Les Demoiselles dâAvignon; defines a new concept of aesthetic attitude; proves the compatibility of Prometheus Challenge artworks with logic; and explains why Plato would have welcomed such artworks in his ideal state
Modeling Impacts of Cold Climates on Vehicle Emissions
This project relates to the research thrust area of âenvironmental impact assessment,' specifically the impact of cold climates on vehicle exhaust emissions. Motor vehicles emit pollutants that are harmful to human. Emissions are thought to be elevated during engine cold starts. During winter, low-lying temperature inversion can trap vehicle emissions near the surface, leading to significantly elevated pollutant concentrations. Despite the importance, vehicle emissions data for cold climates are sparse and the accuracy of vehicle emissions model parameterizations for cold climates is not known. The goal of this project is to improve ability of EPA's Motor Vehicle Emission Simulator (MOVES) model to simulate cold start emissions in cold climate
Experimental study of visual corona under aeronautic pressure conditions using low-cost imaging sensors
Visual corona tests have been broadly applied for identifying the critical corona points of diverse high-voltage devices, although other approaches based on partial discharge or radio interference voltage measurements are also widely applied to detect corona activity. Nevertheless, these two techniques must be applied in screened laboratories, which are scarce and expensive, require sophisticated instrumentation, and typically do not allow location of the discharge points. This paper describes the detection of the visual corona and location of the critical corona points of a sphere-plane gap configurations under different pressure conditions ranging from 100 to 20 kPa, covering the pressures typically found in aeronautic environments. The corona detection is made with a low-cost CMOS imaging sensor from both the visible and ultraviolet (UV) spectrum, which allows detection of the discharge points and their locations, thus significantly reducing the complexity and costs of the instrumentation required while preserving the sensitivity and accuracy of the measurements. The approach proposed in this paper can be applied in aerospace applications to prevent the arc tracking phenomenon, which can lead to catastrophic consequences since there is not a clear protection solution, due to the low levels of leakage current involved in the pre-arc phenomenon.Peer ReviewedPostprint (published version
A âHip-Hopâ Broadway Masterpiece or a Misrepresentation of Hip Hop Culture
In February of 2015, a music sensation hit the streets of New York City and started a revolution across the country. The renowned Lin Manuel Miranda; composer, musician and actor, debuted his six-year creation - an integration of hip hop music into the world of Broadway through the sensational story of Alexander Hamilton. Based off of Ron Chernowâs 2004 biography of Alexander Hamilton, this entirely musical production details the story of the poor immigrant who came to America with big ideas and wrote his way to being a predominate figure in American history (Miranda, 2016). Impressive choreography is combined with powerful lyrics to narrate Alexander Hamiltonâs journey through war, politics, his family and the birth of our nation. Concerned with protecting his legacy and having his voice heard, Hamilton constantly put himself in compromising positions for the greater good of our country. The showâs unconventional structure and use of race bending casting has caused a true Broadway revolution across the country
Protecting the operation from general and residual errors by continuous dynamical decoupling
We study the occurrence of errors in a continuously decoupled two-qubit state
during a quantum operation under decoherence. We consider a
realization of this quantum gate based on the Heisenberg exchange interaction,
which alone suffices for achieving universal quantum computation. Furthermore,
we introduce a continuous-dynamical-decoupling scheme that commutes with the
Heisenberg Hamiltonian to protect it from the amplitude damping and dephasing
errors caused by the system-environment interaction. We consider two
error-protection settings. One protects the qubits from both amplitude damping
and dephasing errors. The other features the amplitude damping as a residual
error and protects the qubits from dephasing errors only. In both settings, we
investigate the interaction of qubits with common and independent environments
separately. We study how errors affect the entanglement and fidelity for
different environmental spectral densities.Comment: Extended version of arXiv:1005.1666. To appear in PR
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