2,575 research outputs found
Development and field testing of a Light Aircraft Oil Surveillance System (LAOSS)
An experimental device consisting of a conventional TV camera with a low light level photo image tube and motor driven polarized filter arrangement was constructed to provide a remote means of discriminating the presence of oil on water surfaces. This polarized light filtering system permitted a series of successive, rapid changes between the vertical and horizontal components of reflected polarized skylight and caused the oil based substances to be more easily observed and identified as a flashing image against a relatively static water surface background. This instrument was flight tested, and the results, with targets of opportunity and more systematic test site data, indicate the potential usefulness of this airborne remote sensing instrument
Simultaneous current-, force- and work function measurement with atomic resolution
The local work function of a surface determines the spatial decay of the
charge density at the Fermi level normal to the surface. Here, we present a
method that enables simultaneous measurements of local work function and
tip-sample forces. A combined dynamic scanning tunneling microscope and atomic
force microscope is used to measure the tunneling current between an
oscillating tip and the sample in real time as a function of the cantilever's
deflection. Atomically resolved work function measurements on a silicon
(111)-() surface are presented and related to concurrently recorded
tunneling current- and force- measurements.Comment: 8 pages, 4 figures, submitted to Applied Physics Letter
Electron beam seals outer surfaces of porous bodies
Porous tungsten plugs provide even airflow for frictionless bearings used in air bearing supported gyros. The plugs have their outer cylindrical surface sealed by an electron beam process to ensure unidirectional airflow through their exit ends
Mesoscopic order and the dimentionality of long-range resonance energy transfer in supramolecular semiconductors
We present time-resolved photoluminescence measurements on two series of
oligo-p-phenylenevinylene materials that self-assemble into supramolecular
nanostructures with thermotropic reversibility in dodecane. One set of
derivatives form chiral, helical stacks while the second set form less
organised, frustrated stacks. Here we study the effects of supramolecular
organisation on the resonance energy transfer rates. We measure these rates in
nanoassemblies formed with mixed blends of oligomers and compare them with the
rates predicted by Foerster theory. Our results and analysis show that control
of supramolecular order in the nanometre lengthscale has a dominant effect on
the efficiency and dimentionality of resonance energy transfer.Comment: 17 Pages, 5 Figures, Submitted to J. Chem. Phy
Statistical mechanics of temporal association in neural networks with transmission delays
We study the representation of static patterns and temporal sequences in neural networks with signal delays and a stochastic parallel dynamics. For a wide class of delay distributions, the asymptotic network behavior can be described by a generalized Gibbs distribution, generated by a novel Lyapunov functional for the determination dynamics. We extend techniques of equilibrium statistical mechanics so as to deal with time-dependent phenomena, derive analytic results for both retrieval quality and storage capacity, and compare them with numerical simulations
Enhancing Public Access to Agency Law
A just, democratic society governed by the rule of law requires that the law be available, not hidden. This principle extends to legal materials produced by administrative agencies, all of which should be made widely accessible to the public. Federal agencies in the United States do disclose online many legal documents—sometimes voluntarily, sometimes in compliance with statutory requirements. But the scope and consistency of these disclosures leaves considerable room for improvement. After conducting a year-long study for the Administrative Conference of the United States, we identified seventeen possible statutory amendments that would improve proactive online disclosure of agency legal materials. Although detailed and sometimes technical, these recommendations can be encapsulated in one simple, succinct principle: All legal materials that agencies are obligated to disclose upon request under the Freedom of Information Act should be affirmatively made accessible to the public on agency websites. Our specific recommendations fall into three main categories: clarification and expansion of the types of legal materials that agencies must disclose affirmatively; specification of the methods of disclosure that will ensure ready accessibility to the public; and establishment of mechanisms that will help ensure agency compliance with these affirmative disclosure requirements. If a democratic government is to be truly transparent, then all its legal materials should be easily available to the public. Congress should take the steps needed to ensure that administrative agencies more consistently and affirmatively disclose all their legal materials in a manner accessible to all
Lorentz angle measurements in irradiated silicon detectors between 77 K and 300 K
Future experiments are using silicon detectors in a high radiation
environment and in high magnetic fields. The radiation tolerance of silicon
improves by cooling it to temperatures below 180 K. At low temperatures the
mobility increases, which leads to larger deflections of the charge carriers by
the Lorentz force. A good knowledge of the Lorentz angle is needed for design
and operation of silicon detectors. We present measurements of the Lorentz
angle between 77 K and 300 K before and after irradiation with a primary beam
of 21 MeV protons.Comment: 13 pages, 9 figures, submitted to ICHEP2000, Osaka, Japa
Disclosure of Agency Legal Materials
This proposed recommendation identifies statutory reforms that, if enacted by Congress, would provide clear standards as to what legal materials agencies must publish and where they must publish them (whether in the Federal Register, on their websites, or elsewhere). The amendments would also account for technological developments and correct certain statutory ambiguities and drafting errors. The objective of these amendments would be to ensure that agencies provide ready public access to important legal materials in the most efficient way possible.
Professor Bernard W. Bell (Rutgers Law School), Professor Cary Coglianese (University of Pennsylvania Law School), Professor Michael Eric Herz (Benjamin N. Cardozo School of Law), Professor Margaret Kwoka (Ohio State University Moritz College of Law), and Professor Orly Lobel (University of San Diego School of Law) are serving as the consultants for this project. Professor Kwoka is serving as the lead consultant.
An Ad Hoc Committee, co-chaired by Public Member Aaron Nielson and Government Member Roxanne Rothschild, considered this project in spring 2023
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