13,314 research outputs found

    Panic on the streets of London

    Get PDF
    The terrorist attacks of 7 July 2005 resulted in a very large redeployment of police officers to central London boroughs. New research by Mirko Draca, Stephen Machin and Robert Witt looks at the impact of this increased security presence on criminal activity in the weeks and months after the bomb blasts

    Use of steepest descent and various approximations for efficient computation of minimum noise aircraft landing trajectories

    Get PDF
    The following areas related to landing trajectory optimization research were discussed: (1) programming and modifying the steepest descent optimization procedure, (2) successfully iterating toward the optimum for a four-mile trajectory, (3) beginning optimization runs for a twenty-mile trajectory, and (4) adapt wind tunnel data for computer usage. Other related areas were discussed in detail in the two previous annual reports

    Phase Transitions for Flat adS Black Holes

    Get PDF
    We reexamine the thermodynamics of adS black holes with Ricci flat horizons using the adS soliton as the thermal background. We find that there is a phase transition which is dependent not only on the temperature, but also on the black hole area, which is an independent parameter. As in the spherical adS black hole, this phase transition is related via the adS/CFT correspondence to a confinement-deconfinement transition in the large N gauge theory on the conformal boundary at infinity.Comment: 5 pages, Revtex, no figures. Minor changes, typos corrected, some references adde

    Optimization and sensitivity studies of flight-path trajectories

    Get PDF
    The optimization of landing trajectories of the Boeing 737 is presented. The primary factor considered was the noise delivered to the population residing near an air terminal but passenger comfort, fuel consumption and time elapsed during the maneuver were also considered. A digital simulation of the aircraft, a noise model and a passenger comfort model, was completed. The digital simulation was made more efficient time-wise. A population model for an urban area was developed and the noise model was integrated into the population model. A steepest descent optimization algorithm was programmed. Some constant glide slope trajectories into an urban Airport were simulated and evaluated with respect to the performance index, and their ground track plotted
    corecore