6,232 research outputs found
Improving Photometry and Astrophotography by Eliminating Dark Frames and Flat Fields
I report on the efforts to improve the dark frames and flat fielding procedure for the charged-coupled device (CCD) camera for the Celestron C14 telescope at the UNH observatory. Dark frames are images taken while the shutter of the camera is closed so that only electronic and dark noise and other internal inconsistencies are recorded. These are important because they allow astronomers to subtract out interference from dark current. Additionally, flat fields are images of the entire field of the telescope so that the brightness in the pixels of the telescopeās field of view is uniform. Flat fields are vital since they provide a consistent illumination for all photos taken from the camera. With the combination of these two features, I was able to optimize the clarity of the telescopeās pictures and show through photometry how the new calibrated images appear in comparison to images prior to the calibration. Overall, these enhanced photographs will assist in achieving better results for future astronomy labs at UNH
Information Content of Polarization Measurements
Information entropy is applied to the state of knowledge of reaction
amplitudes in pseudoscalar meson photoproduction, and a scheme is developed
that quantifies the information content of a measured set of polarization
observables. It is shown that this definition of information is a more
practical measure of the quality of a set of measured observables than whether
the combination is a mathematically complete set. It is also shown that when
experimental uncertainty is introduced, complete sets of measurements do not
necessarily remove ambiguities, and that experiments should strive to measure
as many observables as practical in order to extract amplitudes.Comment: 19 pages, 4 figures; figures updated, minor textual correction
SHRIMP ion probe zircon geochronology and Sr and Nd isotope geochemistry for southern Longwood Range and Bluff Peninsula intrusive rocks of Southland, New Zealand
PermianāJurassic ultramafic to felsic intrusive complexes at Bluff Peninsula and in the southern Longwood Range along the Southland coast represent a series of intraoceanic magmatic arcs with ages spanning a time interval of 110 m.y. New SHRIMP U-Pb zircon data for a quartz diorite from the Flat Hill complex, Bluff Peninsula, yield an age of 259 Ā± 4 Ma, consistent with other geochronological and paleontological evidence confirming a Late Permian age. The new data are consistent with an age of c. 260 Ma for the intrusive rocks of the Brook Street Terrane. SHRIMP U-Pb zircon ages for the southern Longwood Range confirm that intrusions become progressively younger from east to west across the complex. A gabbro at Oraka Point (eastern end of coastal section) has an age of 245 Ā± 4 Ma and shows virtually no evidence of zircon inheritance. The age is significantly different from that of the Brook Street Terrane intrusives. Zircon ages from the western parts of the section are younger and more varied (203ā227 Ma), indicating more complex magmatic histories. A leucogabbro dike from Pahia Point gives the youngest emplacement age of 142 Ma, which is similar to published U-Pb zircon ages for the Anglem Complex and Paterson Group on Stewart Island
Papermaking in Maine: Economic Trends from 1894 to 2000
This essay reviews the major economic trends in Maineās paper industry since the late nineteenth century. It sets the context at national and regional levels, offers a broad statistical picture of the industryās production in Maine, and concludes with a focus on Maineās āmill towns.ā Paper production is a branch of a larger industry that converts primary ļ¬ber ā logs, chips, wastepaper, rags, or market pulp ā into paper
Selection of an alternative production part approval process to improve weapon systems production readiness
This thesis conducted an examination related to the Department of Defense (DOD) weapons systems production approval practices. Current practices result in poor weapons system production outcomes that reduce fleet readiness in DOD weapons systems acquisition. The Government Accountability Office (GAO) has reported concerns related to a lack of manufacturing knowledge at production start as causal to poor production outcomes. A comparison of DOD practices against non-DOD industrial production approval processes addressing causality and improvement opportunity provided new insight not found in acquisition research. An analysis of alternatives identified best practices to improve production capability and readiness. Key findings revealed that the automotive production approval process followed industry best practices that fully addressed problems identified by the GAO. Non-DOD industries used a more prescriptive Quality Management System (QMS) that enabled a more disciplined manufacturing development and demonstration of production capability prior to production commitment. Commercial surveys in the literature confirmed the benefits of the automotive prescriptive QMS. The more successful QMS approach can be applied to DOD acquisition practices reducing costs and improving fleet readiness.http://archive.org/details/selectionofnlter1094556139Civilian, Department of the NavyApproved for public release; distribution is unlimited
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