3,479 research outputs found
Semi-realistic nucleon-nucleon interactions with improved neutron-matter properties
New parameter-sets of the semi-realistic nucleon-nucleon interaction are
developed, by modifying the M3Y interaction but maintaining the tensor channels
and the longest-range central channels. The modification is made so as to
reproduce microscopic results of neutron-matter energies, in addition to the
measured binding energies of doubly magic nuclei including Sn and the
even-odd mass differences of the Z=50 and N=82 nuclei in the self-consistent
mean-field calculations. Separation energies of the proton- or neutron-magic
nuclei are shown to be in fair agreement with the experimental data. With the
new parameter-sets M3Y-P6 and P7, the isotropic spin-saturated symmetric
nuclear matter remains stable in the density range as wide as , while keeping desirable results of the previous parameter-set on
finite nuclei. Isotope shifts of the Pb nuclei and tensor-force effects on
shell structure are discussed.Comment: 18 pages including 7 figure
Monoenergetic Neutrino Beam for Long Baseline Experiments
In an electron capture process by a nucleus, emitted neutrinos are
monoenergetic. By making use of it, we study how to get a completely
monoenergetic neutrino beam in a long baseline experiment.Comment: 9 pages, no figure, som typos are corrected, e.g. equation number
quoted in table I is correcte
SeaWiFS technical report series. Volume 6: SeaWiFS technical report series cumulative index: Volumes 1-5
The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) is the follow-on ocean color instrument to the Coastal Zone Color Scanner (CZCS), which ceased operations in 1986, after an eight year mission. SeaWiFS is expected to be launched in August 1993, on the Sea Star satellite, being built by Orbital Sciences Corporation (OSC). The SeaWiFS Project at the NASA/Goddard Space Flight Center (GSFC) has undertaken the responsibility of documenting all aspects of this mission, which is critical to the ocean color and marine science communities. This documentation, entitled the SeaWiFS Technical Report Series, is in the form of NASA Technical Memoranda Number 104566. All reports published are volumes within the series. This volume serves as a reference, or guidebook, to the previous five volumes and consists of four main sections including an index to key words and phrases, a list of all references cited, and lists of acronyms and symbols used. It is our intention to publish a summary index of this type after every five volumes in the series. This will cover the topics published in all previous editions of the indices, that is, each new index will include all of the information contained in the preceding indices
Space processing of chalcogenide glass
A program was conducted to develop the technique of space processing for chalcogenide glass, and to define the process and equipment necessary. In the course of this program, successful long term levitation of objects in a 1-g environment was achieved. Glass beads 4 mm diameter were containerless melted and fused together
Creep of plasma sprayed zirconia
Specimens of plasma-sprayed zirconia thermal barrier coatings with three different porosities and different initial particle sizes were deformed in compression at initial loads of 1000, 2000, and 3500 psi and temperatures of 1100 C, 1250 C, and 1400 C. The coatings were stabilized with lime, magnesia, and two different concentrations of yttria. Creep began as soon as the load was applied and continued at a constantly decreasing rate until the load was removed. Temperature and stabilization had a pronounced effect on creep rate. The creep rate for 20% Y2O3-80% ZrO2 was 1/3 to 1/2 that of 8% Y2O3-92% ZrO2. Both magnesia and calcia stabilized ZrO2 crept at a rate 5 to 10 times that of the 20% Y2O3 material. A near proportionality between creep rate and applied stress was observed. The rate controlling process appeared to be thermally activated, with an activation energy of approximately 100 cal/gm mole K. Creep deformation was due to cracking and particle sliding
"Valuing the Visual Disamenity of Offshore Wind Projects at Varying Distances from the Shore: An Application on the Delaware Shoreline"
Several offshore wind power projects are under consideration in the United States. A concern with any wind power project is the visual disamenity it may create. Using a stated preference choice model, we estimated the external costs to residents of the State of Delaware for offshore wind turbines located at different distances from the coast. The annual costs to inland residents was 9, 0 (200680, 35, and $27 for the same increments.Windfarms, View Disamenity, Valuation
SeaWiFS Technical Report Series. Volume 7: Cloud screening for polar orbiting visible and infrared (IR) satellite sensors
Methods for detecting and screening cloud contamination from satellite derived visible and infrared data are reviewed in this document. The methods are applicable to past, present, and future polar orbiting satellite radiometers. Such instruments include the Coastal Zone Color Scanner (CZCS), operational from 1978 through 1986; the Advanced Very High Resolution Radiometer (AVHRR); the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), scheduled for launch in August 1993; and the Moderate Resolution Imaging Spectrometer (IMODIS). Constant threshold methods are the least demanding computationally, and often provide adequate results. An improvement to these methods are the least demanding computationally, and often provide adequate results. An improvement to these methods is to determine the thresholds dynamically by adjusting them according to the areal and temporal distributions of the surrounding pixels. Spatial coherence methods set thresholds based on the expected spatial variability of the data. Other statistically derived methods and various combinations of basic methods are also reviewed. The complexity of the methods is ultimately limited by the computing resources. Finally, some criteria for evaluating cloud screening methods are discussed
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