Showing papers in "CTIT technical reports series in 1994"

The paradoxes of deontic logic revisited: a computer science perspective

Abstract: This paper revisits a number of well-known paradoxes of deontic logic, namely Ross'paradox (if you ought to mail a letter, you ought to mail or burn it), the free choice paradox (if you are permitted to mail a letter, you are permitted to mail or burn it), the paradox of No Conflicting Obligations (ought implies permitted), the Good Samaritan Paradox (if you ought to help Jones who is robbed, then Jones ought to be robbed) and Chisholm's paradox (if you ought to do A, and if A ought to imply B, and not A implies that you ought to do not B, then this is inconsistent with doing not A). Framing these paradoxes in dynamic logic removes some of them and sheds light on others. This paper is based on an invited talk presented at DEON'94.

Analysis of random structure-acoustic interaction problems using coupled boundary element and finite element methods

Abstract: A coupled boundary element (BEM)-finite element (FEM) approach is presented to accurately model structure-acoustic interaction systems. The boundary element method is first applied to interior, two and three-dimensional acoustic domains with complex geometry configurations. Boundary element results are very accurate when compared with limited exact solutions. Structure-interaction problems are then analyzed with the coupled FEM-BEM method, where the finite element method models the structure and the boundary element method models the interior acoustic domain. The coupled analysis is compared with exact and experimental results for a simplistic model. Composite panels are analyzed and compared with isotropic results. The coupled method is then extended for random excitation. Random excitation results are compared with uncoupled results for isotropic and composite panels.

Reentry Vehicle On-Site Inspection Technology Study

Abstract: : A study group was tasked to develop possible reentry vehicle on-site inspection (RVOSI) scenarios and to recommend research into technologies that could address these scenarios. The task was accomplished by identifying RVOSI technology candidates and evaluating their advantages or disadvantages to comparison to the visual protocol for RVOSI prescribed by the Strategic Arms Reduction Treaty (START) on the Reduction and Limitation of Strategic Offensive Arms. RVOIS technologies were evaluated with regard to inspection confidence, cost, intrusiveness, operational impact, and inspector burden. The RVOSI technology Study identified no technology that readily solves the problems associated with START-prescribed visual inspection protocols. Recommendations for (1) further research in analytic modeling, (2) experimental studies to support this analytic work, and (3) data processing resulted from this study. Technology development for RVOIS appears to be primarily of interest if the technology provides enhanced confidence or additional inspection capability over visual inspections. Reentry vehicle, Treaty verification technology, On-site inspection, Strategic Arms Reduction Treaty (START).

Nanoscale imaging of molecular adsorption

Abstract: In situ atomic force microscope observations were made of the adsorption of anions (1– or 2–) of the organic diacid 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid from aqueous solution onto the (0001) surface of hydrotalcite (HT), a layered clay. This adsorption process is believed to mimic the ion-exchange reactions that occur within the layers of HT and other layered clays. Atomic force microscope images of the (0001) surfaces of HT, acquired in aqueous solutions, reveal an ordered structure with respect to magnesium and aluminum atoms. In the presence of the anions, atomic force microscopy indicates pH-dependent adsorption onto the formally cationic HT surface. The anion coverage is governed by electroneutrality and steric interactions between the bulky anions within the adsorbed layer, whereas the orientation of the anions with respect to the HT surface is dictated by coulombic interactions and hydrogen bonding between the anion9s sulfonate moiety and clay hydroxyl triads. These observations reveal that the reversible adsorption of molecular species can be examined directly by in situ atomic force microscopy, providing details of surface stoichiometry and adlayer symmetry on the local, molecular level.

Progress in the production of samples of gamma ray laser candidate materials

Abstract: : Studies of the 29 possible candidates to use as the working medium of a gamma ray laser have identified the 31-year isomer of Hafnium-178 as the best This research is aimed at the development of a production cycle for this rare substance A major success of this year's work has been the discovery in byproduct debris from the synthesis of medical isotopes of a quantity of this material equal to 99% of the world's inventory Chemical conditioning and recovery of this sample have been initiated Also, an evaluation was made of the 142 reactions with potential for restocking the existing inventories (AN)

Log-Polar Optical Coordinate Transformation with Applications for Automatic Pattern Recognition

Abstract: : An important task in machine vision and target recognition is the rapid estimation of the orientation and size of an object with respect to a reference. An optical image processing system is described which converts in- plane rotation and size variations into shift properties using log-polar coordinate transforms. The optical system consists of a binary optical element, which performs the log-polar coordinate transform of the input image, a Fourier transform lens, a Michelson interferometer and a CCD camera for collecting the scale/rotation invariant output. The Michelson interferometer produces two identical patterns on the polar axis to prevent wraparound effects of the coordinate transform. Results are presented in terms of capability in estimating the rotation and size of simple images and discriminating between similar in- class and out-of-class images using the output of a binary phase-only correlator. Pattern recognition, Phase-only filters, Image processing. Space- variant sensing.

Scientific and Technical Support for the Galileo Net Flux Radiometer Experiment

Abstract: This report describes work in support of the Galileo Net Flux Radiometer (NFR), an instrument mounted on the Galileo probe, a spacecraft designed for entry into and direct measurements of Jupiter's atmosphere. Tasks originally proposed for the post launch period are briefly as follows: attend and support PSG (Project Science Group) and other project science meetings; support in-flight checkouts; maintain and keep safe the spare instrument and GSE (Ground Support Equipment); organize and maintain documentation; finish NFR calibration measurements, documentation, and analysis; characterize and diagnose instrument anomalies; develop descent data analysis tools; and science data analysis and publication. Because we had the capability to satisfy a project support need we also subsequently proposed and were funded to make ground- based observations of Jupiter during the period surrounding the Galileo arrival at Jupiter, using the Swedish Solar Telescope at La Palma, Canary Islands. The following section (11) provides background information on the NFR instrument.