9,088 research outputs found
Generating the Fukaya categories of compact toric varieties
Let be a compact toric variety. The quantum cohomology of decomposes
as a direct sum, and associated to each summand is a toric fibre with
rank local system. By building an explicit twisted-complex-like object, we
show that on the Kodaira-Spencer isomorphism of Fukaya-Oh-Ohta-Ono factors
through the closed-open string map to the Hochschild cohomology of . We
deduce that the latter is injective and hence, assuming an appropriate version
of Abouzaid's criterion, that split generates the corresponding summand
of the Fukaya category.Comment: 19 pages, comments welcom
The Anchorage, Alaska Veterans Court and Recidivism: July 6, 2004 – December 31, 2010
In July 2004 Anchorage, Alaska started one of the first veterans courts in the United States. That court has now been in continuous operation for over seven years. This Comment briefly describes the steps taken to establish the Alaska Veterans Court and how the court operates. An overview of the characteristics of participants in and graduates from the court is provided, followed by statistics concerning the effect of the court on recidivism. Several potential future areas of study concerning this court are also identified. The Comment concludes by highlighting the importance of the court and by noting that the benefits provided by the court are currently limited by the absence of funding from any source
Net phytoplankton and zooplankton in the New York Bight, January 1976 to February 1978, with comments on the effects of wind, Gulf Stream eddies, and slope water intrusions
Results are given of monthly net phytoplankton and zooplankton sampling from a 10 m depth in shelf, slope, and Gulf Stream eddy water along a transect running southeastward from Ambrose Light, New York, in 1976, 1977, and early 1978. Plankton abundance and temperature at 10 m and sea surface salinity at each station are listed. The effects of atmospheric forcing and Gulf Stream eddies on plankton distribution and abundance arc discussed. The frequency of Gulf Stream eddy passage through the New York Bight corresponded with the frequency of tropical-subtropical net phytoplankton in the samples. Gulf Stream eddies injected tropical-subtropical zooplankton onto the shelf and removed shelfwater and its entrained zooplankton.
Wind-induced offshore Ekman transport corresponded generally with the unusual timing of two net phytoplankton
maxima. Midsummer net phytoplankton maxima were recorded following the passage of Hurricane Belle (August 1976) and a cold front (July 1977). Tropical-subtropical zooplankton which had been injected onto the outer shelf by Gulf Stream eddies were moved to the inner shelf by a wind-induced current moving up the Hudson Shelf Valley. (PDF file contains 47 pages.
Flow studies in close-coupled ventral nozzles for STOVL aircraft
Flow in a generic ventral nozzle system was studied experimentally and analytically with the PARC3D computational fluid dynamics program in order to evaluate the program's ability to predict system performance and internal flow patterns. A generic model of a tailpipe with a rectangular ventral nozzle, about 1/3 of full size, was tested with unheated air at steady state pressure ratios up to 4.0. The end of the tailpipe was closed to simulate a blocked exhaust nozzle. Flow behavior into and through the ventral duct is discussed and illustrated with paint streak flow visualization photographs. PARC3D graphic images are shown for comparison with the experimental photographs. The program successfully predicted internal flow patterns; it also computed thrust and discharge coefficients within 1 pct. of measured values
Experimental and analytical study of close-coupled ventral nozzles for ASTOVL aircraft
Flow in a generic ventral nozzle system was studied experimentally and analytically with a block version of the PARC3D computational fluid dynamics program (a full Navier-Stokes equation solver) in order to evaluate the program's ability to predict system performance and internal flow patterns. For the experimental work a one-third-size model tailpipe with a single large rectangular ventral nozzle mounted normal to the tailpipe axis was tested with unheated air at steady-state pressure ratios up to 4.0. The end of the tailpipe was closed to simulate a blocked exhaust nozzle. Measurements showed about 5 1/2 percent flow-turning loss, reasonable nozzle performance coefficients, and a significant aftward axial component of thrust due to flow turning loss, reasonable nozzle performance coefficients, and a significant aftward axial component of thrust due to flow turning more than 90 deg. Flow behavior into and through the ventral duct is discussed and illustrated with paint streak flow visualization photographs. For the analytical work the same ventral system configuration was modeled with two computational grids to evaluate the effect of grid density. Both grids gave good results. The finer-grid solution produced more detailed flow patterns and predicted performance parameters, such as thrust and discharge coefficient, within 1 percent of the measured values. PARC3D flow visualization images are shown for comparison with the paint streak photographs. Modeling and computational issues encountered in the analytical work are discussed
The remotely piloted vehicle as an earth science research aircraft
A brief study was conducted at the Goddard Space Flight Center to identify existing remotely piloted vehicle (RPV) capabilities and to determine if the use of an RPV was advantageous and practical for Earth science investigations. A total of 17 instrument systems were identified. It was found that RPV's were considered especially valuable for dangerous missions, e.g., flights through volcano plumes and hurricanes, long duration profiles over inaccessible regions such as the Antarctic, and very low altitude ocean profiling missions
The natural resources of Agua Hedionda Lagoon
This report has been prepared under contract to and fully funded by the Office of Biological Services of the U. S. Fish and Wildlife Service. The goals and purpose of this federal office are to review the impact on fish and wildlife resources of land, mineral and water development practices, such as offshore oil and gas exploration, development and production; construction of inshore pipeline canals and refineries; power plant construction/operation and urban development. This report, and five other southern California reports, covering Carpinteria Marsh (Santa Barbara County), Anaheim Bay-Huntington Harbor (Orange County), Mugu Lagoon (Ventura County), the Northern Santa Barbara County Coastal
Wetlands, and the Nipomo Dunes and Wetlands (San Luis Obispo County), are scheduled to be part of the Department's "Coastal Wetland Series" (see inside front cover). (154 pp.
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