15,468 research outputs found
ATLAS RPC offline monitoring and data quality assessment
In this work several aspects of ATLAS RPC offline monitoring and data quality
assessment are illustrated with cosmics data selected by RPC trigger. These
correspond to trigger selection, front-end mapping, detection efficiency and
occupancy, which are studied in terms of low level quantities such as: RPC
off-line hits and standalone tracks. The tools and techniques presented are
also extended to the forthcoming LHC p-p beam collisions.Comment: Poster section at ICHEP08, Philadelphia, USA, July 2008. 3 pages,
LaTeX, 3 eps figure
Hypertemporal Imaging of NYC Grid Dynamics
Hypertemporal visible imaging of an urban lightscape can reveal the phase of
the electrical grid granular to individual housing units. In contrast to
in-situ monitoring or metering, this method offers broad, persistent,
real-time, and non-permissive coverage through a single camera sited at an
urban vantage point. Rapid changes in the phase of individual housing units
signal changes in load (e.g., appliances turning on and off), while slower
building- or neighborhood-level changes can indicate the health of distribution
transformers. We demonstrate the concept by observing the 120 Hz flicker of
lights across a NYC skyline. A liquid crystal shutter driven at 119.75 Hz
down-converts the flicker to 0.25 Hz, which is imaged at a 4 Hz cadence by an
inexpensive CCD camera; the grid phase of each source is determined by analysis
of its sinusoidal light curve over an imaging "burst" of some 25 seconds.
Analysis of bursts taken at ~15 minute cadence over several hours demonstrates
both the stability and variation of phases of halogen, incandescent, and some
fluorescent lights. Correlation of such results with ground-truth data will
validate a method that could be applied to better monitor electricity
consumption and distribution in both developed and developing cities.Comment: This paper uses astronomical techniques applied to the study of urban
lights. This research is reproducible but the data access is restricted. A
Github repository contains all code supporting this research as well as
additional material: https://github.com/fedhere/detect12
Jane E. Bianco to Mr. Meredith (11 October 1962)
https://egrove.olemiss.edu/mercorr_pro/1075/thumbnail.jp
A Robust Filter for the BeppoSAX Gamma Ray Burst Monitor Triggers
The BeppoSAX Gamma Ray Burst Monitor (GRBM) is triggered any time a
statistically significant counting excess is simultaneously revealed by at
least two of its four independent detectors. Several spurious effects,
including highly ionizing particles crossing two detectors, are recorded as
onboard triggers. In fact, a large number of false triggers is detected, in the
order of 10/day. A software code, based on an heuristic algorithm, was written
to discriminate between real and false triggers. We present the results of the
analysis on an homogeneous sample of GRBM triggers, thus providing an estimate
of the efficiency of the GRB detection system consisting of the GRBM and the
software.Comment: Proc. 5th Huntsville GRB Symposiu
Scheduling aircraft landings - the static case
This is the publisher version of the article, obtained from the link below.In this paper, we consider the problem of scheduling aircraft (plane) landings at an airport. This problem is one of deciding a landing time for each plane such that each plane lands within a predetermined time window and that separation criteria between the landing of a plane and the landing of all successive planes are respected. We present a mixed-integer zeroâone formulation of the problem for the single runway case and extend it to the multiple runway case. We strengthen the linear programming relaxations of these formulations by introducing additional constraints. Throughout, we discuss how our formulations can be used to model a number of issues (choice of objective function, precedence restrictions, restricting the number of landings in a given time period, runway workload balancing) commonly encountered in practice. The problem is solved optimally using linear programming-based tree search. We also present an effective heuristic algorithm for the problem. Computational results for both the heuristic and the optimal algorithm are presented for a number of test problems involving up to 50 planes and four runways.J.E.Beasley. would like to acknowledge the financial support of the Commonwealth Scientific and Industrial Research Organization, Australia
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