1,449 research outputs found
Tracking Vector Magnetograms with the Magnetic Induction Equation
The differential affine velocity estimator (DAVE) developed in Schuck (2006)
for estimating velocities from line-of-sight magnetograms is modified to
directly incorporate horizontal magnetic fields to produce a differential
affine velocity estimator for vector magnetograms (DAVE4VM). The DAVE4VM's
performance is demonstrated on the synthetic data from the anelastic
pseudospectral ANMHD simulations that were used in the recent comparison of
velocity inversion techniques by Welsch (2007). The DAVE4VM predicts roughly
95% of the helicity rate and 75% of the power transmitted through the
simulation slice. Inter-comparison between DAVE4VM and DAVE and further
analysis of the DAVE method demonstrates that line-of-sight tracking methods
capture the shearing motion of magnetic footpoints but are insensitive to flux
emergence -- the velocities determined from line-of-sight methods are more
consistent with horizontal plasma velocities than with flux transport
velocities. These results suggest that previous studies that rely on velocities
determined from line-of-sight methods such as the DAVE or local correlation
tracking may substantially misrepresent the total helicity rates and power
through the photosphere.Comment: 30 pages, 13 figure
CHEMICAL CONTROL OF DEPREDATING BLACKBIRDS IN ONTARIO FIELD CORN
Corn depredation by red·winged blackbirds (Agelaius phoeniceus) has been an agricultural problem in southwestern Ontario for many years. Large marsh areas along the shoreline of Lakes Erie and St. Clair provide ideal habitat for breeding and roosting. Concurrently, the vast monocultural field corn acreages in Kent and Essex Counties have over the years been the centers for blackbird depredation in the province. The expansion of corn production into other areas of Ontario has, however, resulted in a province·wide distribution of damage, and substantial crop losses for specific individual farmers (Tyler and Kannenberg, 1980). The Ontario Ministry of the Environment (OME) provided funding for a four·year research program on the importance, ecology and control of blackbirds in 1976 following mounting concern by Ontario corn producers. Dyer (1968) completed a major study on red-winged blackbirds in Dover Township, Kent County during the period 1964-68; however, the evaluation of 4-AP efficacy was a minor component of the project (Dyer, 1976). Thus, the OME required efficacy data on 4-AP for current Ontario conditions for registration purposes, regardless of the 1972 registration in the U.S.A. Methiocarb (3,5-dimethyl-4(methylthio) phenol methylcarbamate) (Mesurol®, Mobay Chemical Corp.) was also a candidate compound because of the known taste aversion properties (Rcigers, 1974; Crase and Dehaven, 1976). Again, the OME required data on the efficacy of methiocarb as a bird repellent in ripening field corn. Research on the potential for lethal roost control was an initial objective; however, this component of chemical control was not pursued. Conversely, lethal control at foraging sites was not an initial objective, however, ecological studies completed (Somers et aI., 1981b) suggested that the use of toxicants in a corn field may have potential. Pilot studies using Starlicide® (Ralston-Purina Co.) and a-chloralose at foraging sites were completed to evaluate this hypothesis
Ecology and Management of Depredating Blackbirds in Ontario Field Corn
Blackbird damage to field corn in southwestern Ontario has been a problem for farmers for many years (Whitney 1954; Dyer 1968). Historically, Kent and Essex counties were the major corn-growing regions in Ontario, and the most significant centers of corn depredation by blackbirds were in these counties. However, the development of new short-season cultivars has afforded the expansion of field corn production and corn depredation problems throughout southern Ontario. The Ontario Ministry of the Environment (OME) provided funding commencing in 1976 in response to these increased instances of corn depredation for a 4-year research program on the importance, ecology and control of blackbirds
Heritage Matters- January 2007
INSIDE THIS ISSUE
Conferences upcoming, p. 10
Grant applications, p. 11
Internships, p. 3
National Register listings, p. 5
Tribal Preservation Officer list, p. 9
CONTENTS
NPS ACTIVITIES, pages 2-4
Inupiaq Heritage in Northwestern Alaska, p. 2
Cultural Resources Diversity Internship Program, p. 3
Historic Trees, the National Park Service, and History, p. 3
STATE INITIATIVES, pages 5-8
National Register Nominations, p. 5 • Ridge Trail Historic District, Walsh and Pembina Counties, North Dakota • Emery Hall, Wilberforce University, Green County, Ohio • Ponca Agency, Boyd County, Nebraska • Ohio Theatre, Toledo, Ohio • Hydaburg Totem Park, Hydaburg, Alaska • Sunrise Mine Historic District, eastern Wyoming • Pilsen Historic District, Chicago, Illinois
TRIBAL INITIATIVES, pages 8-9
NAGPRA Develops New Outreach Initiatives, p. 8
Current THPO Listings, p. 9
CONFERENCES, ANNOUNCEMENTS, AND EVENTS, pages 10-11
Conferences, p. 10
Vernacular Architectural Forum Annual Meeting in Savannah, p. 10
Organization of American Historians Annual Meeting in Minneapolis, p. 10
US/ICOMOS International Symposium on Heritage Tourism in San Francisco, p. 10
Arkansas Historical Association Conference in Little Rock, p. 10
American Association of Museums Annual Meeting in Chicago, p. 11
National Trust for Historic Preservation National Preservation Conference in St. Paul, p. 11
Announcements, p. 11
Preserve America Grant Applications, p. 11
Save America’s Treasures Grant Applications, p. 11
Events, p. 11
Preservation-related Commemorations, p. 1
Heritage Matters- January 2007
INSIDE THIS ISSUE
Conferences upcoming, p. 10
Grant applications, p. 11
Internships, p. 3
National Register listings, p. 5
Tribal Preservation Officer list, p. 9
CONTENTS
NPS ACTIVITIES, pages 2-4
Inupiaq Heritage in Northwestern Alaska, p. 2
Cultural Resources Diversity Internship Program, p. 3
Historic Trees, the National Park Service, and History, p. 3
STATE INITIATIVES, pages 5-8
National Register Nominations, p. 5 • Ridge Trail Historic District, Walsh and Pembina Counties, North Dakota • Emery Hall, Wilberforce University, Green County, Ohio • Ponca Agency, Boyd County, Nebraska • Ohio Theatre, Toledo, Ohio • Hydaburg Totem Park, Hydaburg, Alaska • Sunrise Mine Historic District, eastern Wyoming • Pilsen Historic District, Chicago, Illinois
TRIBAL INITIATIVES, pages 8-9
NAGPRA Develops New Outreach Initiatives, p. 8
Current THPO Listings, p. 9
CONFERENCES, ANNOUNCEMENTS, AND EVENTS, pages 10-11
Conferences, p. 10
Vernacular Architectural Forum Annual Meeting in Savannah, p. 10
Organization of American Historians Annual Meeting in Minneapolis, p. 10
US/ICOMOS International Symposium on Heritage Tourism in San Francisco, p. 10
Arkansas Historical Association Conference in Little Rock, p. 10
American Association of Museums Annual Meeting in Chicago, p. 11
National Trust for Historic Preservation National Preservation Conference in St. Paul, p. 11
Announcements, p. 11
Preserve America Grant Applications, p. 11
Save America’s Treasures Grant Applications, p. 11
Events, p. 11
Preservation-related Commemorations, p. 1
Heritage Matters- July 2005
INSIDE THIS ISSUE
Conferences upcoming, p. 17
National Historic Landmark designations, p. 3
National Register nominations, p. 8
Publication of note, p. 18
CONTENTS
NPS ACTIVITIES, pages 1–5
Cultures of a Country, p. 1
National Historic Landmarks designated, p. 3
Preserve and Play Conference, p. 4
PARTNERS’ ACTIVITIES, pages 6–7
Seminar, Public Meaning of Archeological Heritage, p. 6
AAM Annual Meeting 2005 report, p. 7
STATE ACTIVITIES, pages 8-15
National Register Nominations, p. 8 • Pascua Cultural Center, Tucson, Arizona • Town Doctor’s House and Site, Southold, New York • Louis J. Bailey Branch Library—Gary International Institute, Gary, Indiana • Our Savior’s Scandinavian Lutheran Church, Kenaston, North Dakota • B’nai Jacob Synagogue, Ottumna, Iowa • Whitepath and Fly Smith Gravesite, Hopkinsville, Kentucky • Winnemucca Hotel, Humboldt County, Nevada • Government Boarding School at Lac de Flambeau, Wisconsin • Ivey Delph Apartments, New York City • Edificio Patio Español, San Juan, Puerto Rico
POINT OF VIEW, page 16
The Original Mason-Dixon Line, p. 16
CONFERENCES AND NOTICES, pages 17–19
Conferences, p. 17 • Multicultural Days: An International Perspective Conference, St. Catherines, Ontario, Canada • 5th International Conference on Diversity in Organizations, Communities and Nations, Bejing, China • 2005 Pecos Conference, White Rock, New Mexico • Graduate Association for African-American History at the University of Memphis, Memphis, Tennessee • SACRPH Biennial Conference, Coral Gables, Florida • American Studies Association Annual Conference, Washington, DC • Call for Papers: Mid-Atlantic Popular/American Culture Association Annual Conference, New Brunswick, New Jersey • Call for Papers: Association for Museum History Annual Conference, Washington, DC
Notices, p. 18
Asian Reflections on the American Landscape Available
Assistance Needed for Untold Stories and Unsung Heroes in the Making of the National Park
Robust Chauvenet Outlier Rejection
Sigma clipping is commonly used in astronomy for outlier rejection, but the
number of standard deviations beyond which one should clip data from a sample
ultimately depends on the size of the sample. Chauvenet rejection is one of the
oldest, and simplest, ways to account for this, but, like sigma clipping,
depends on the sample's mean and standard deviation, neither of which are
robust quantities: Both are easily contaminated by the very outliers they are
being used to reject. Many, more robust measures of central tendency, and of
sample deviation, exist, but each has a tradeoff with precision. Here, we
demonstrate that outlier rejection can be both very robust and very precise if
decreasingly robust but increasingly precise techniques are applied in
sequence. To this end, we present a variation on Chauvenet rejection that we
call "robust" Chauvenet rejection (RCR), which uses three decreasingly
robust/increasingly precise measures of central tendency, and four decreasingly
robust/increasingly precise measures of sample deviation. We show this
sequential approach to be very effective for a wide variety of contaminant
types, even when a significant -- even dominant -- fraction of the sample is
contaminated, and especially when the contaminants are strong. Furthermore, we
have developed a bulk-rejection variant, to significantly decrease computing
times, and RCR can be applied both to weighted data, and when fitting
parameterized models to data. We present aperture photometry in a contaminated,
crowded field as an example. RCR may be used by anyone at
https://skynet.unc.edu/rcr, and source code is available there as well.Comment: 62 pages, 48 figures, 7 tables, accepted for publication in ApJ
Association of personality on changes in weekday sitting time: cross-sectional and prospective evaluation
Background: The purpose of this study was to examine the prospective association of personality typology on changes in sitting (sedentary) time.
Methods: Young adults (N = 126; Mage = 21.6 yrs) completed self-report assessments of personality and sitting time at baseline and at an approximate 5-month follow-up. At baseline, personality was assessed via the Neuroticism-Extraversion-Openness Five Factor Inventory (NEO-FFI) questionnaire. At both baseline and the follow-up period, sitting time was self-reported using the International Physical Activity Questionnaire (IPAQ) short form.
Results: Both extraversion (β = –5.8; 95% CI: –11.7, 0.21; p = 0.05) and conscientiousness (β = –5.7; 95% CI: –11.3, –0.2; p = 0.04) were inversely associated with baseline sitting time. Regarding the prospective results, the only personality trait associated with changes in sitting time was openness to experience. Independent of changes in physical activity as well as other potential confounders, for every 1 unit increase in openness to experience, there was an associated 6.6 min/day increased change score in sitting time over the 5-month follow-up period (β = 6.6; 95% CI: 0.13, 13.0; p = 0.04).
Conclusion: Personality was differentially associated with sitting time based on the study design, with the personality trait of openness to experience being prospectively associated with increases in sitting time
Finite pseudo orbit expansions for spectral quantities of quantum graphs
We investigate spectral quantities of quantum graphs by expanding them as
sums over pseudo orbits, sets of periodic orbits. Only a finite collection of
pseudo orbits which are irreducible and where the total number of bonds is less
than or equal to the number of bonds of the graph appear, analogous to a cut
off at half the Heisenberg time. The calculation simplifies previous approaches
to pseudo orbit expansions on graphs. We formulate coefficients of the
characteristic polynomial and derive a secular equation in terms of the
irreducible pseudo orbits. From the secular equation, whose roots provide the
graph spectrum, the zeta function is derived using the argument principle. The
spectral zeta function enables quantities, such as the spectral determinant and
vacuum energy, to be obtained directly as finite expansions over the set of
short irreducible pseudo orbits.Comment: 23 pages, 4 figures, typos corrected, references added, vacuum energy
calculation expande
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