25,109 research outputs found
Application of remote sensing technology to land evaluation, planning utilization of land resources, and assessment of westland habitat in eastern South Dakota, parts 1 and 2
The author has identified the following significant results. LANDSAT fulfilled the requirements for general soils and land use information. RB-57 imagery was required to provide the information and detail needed for mapping soils for land evaluation. Soils maps for land evaluation were provided on clear mylar at the scale of the county highway map to aid users in locating mapping units. Resulting mapped data were computer processed to provided a series of interpretive maps (land value, limitations to development, etc.) and area summaries for the users
Assembly and analysis of fragmentation data for liquid propellant vessels
Fragmentation data was assembled and analyzed for exploding liquid propellant vessels. These data were to be retrieved from reports of tests and accidents, including measurements or estimates of blast yield, etc. A significant amount of data was retrieved from a series of tests conducted for measurement of blast and fireball effects of liquid propellant explosions (Project PYRO), a few well-documented accident reports, and a series of tests to determine auto-ignition properties of mixing liquid propellants. The data were reduced and fitted to various statistical functions. Comparisons were made with methods of prediction for blast yield, initial fragment velocities, and fragment range. Reasonably good correlation was achieved. Methods presented in the report allow prediction of fragment patterns, given type and quantity of propellant, type of accident, and time of propellant mixing
Large Interstellar Polarisation Survey II. UV/optical study of cloud-to-cloud variations of dust in the diffuse ISM
It is well known that the dust properties of the diffuse interstellar medium
exhibit variations towards different sight-lines on a large scale. We have
investigated the variability of the dust characteristics on a small scale, and
from cloud-to-cloud. We use low-resolution spectro-polarimetric data obtained
in the context of the Large Interstellar Polarisation Survey (LIPS) towards 59
sight-lines in the Southern Hemisphere, and we fit these data using a dust
model composed of silicate and carbon particles with sizes from the molecular
to the sub-micrometre domain. Large (> 6 nm) silicates of prolate shape account
for the observed polarisation. For 32 sight-lines we complement our data set
with UVES archive high-resolution spectra, which enable us to establish the
presence of single-cloud or multiple-clouds towards individual sight-lines. We
find that the majority of these 35 sight-lines intersect two or more clouds,
while eight of them are dominated by a single absorbing cloud. We confirm
several correlations between extinction and parameters of the Serkowski law
with dust parameters, but we also find previously undetected correlations
between these parameters that are valid only in single-cloud sight-lines. We
find that interstellar polarisation from multiple-clouds is smaller than from
single-cloud sight-lines, showing that the presence of a second or more clouds
depolarises the incoming radiation. We find large variations of the dust
characteristics from cloud-to-cloud. However, when we average a sufficiently
large number of clouds in single-cloud or multiple-cloud sight-lines, we always
retrieve similar mean dust parameters. The typical dust abundances of the
single-cloud cases are [C]/[H] = 92 ppm and [Si]/[H] = 20 ppm.Comment: A&A accepte
Intermediate Wakimoto modules for Affine sl(n+1)
We construct certain boson type realizations of affine sl(n+1) that depend on
a parameter r. When r=0 we get a Fock space realization of Imaginary Verma
modules appearing in the work of the first author and when r=n they are the
Wakimoto modules described in the work of Feigin and Frenkel
Picard group of hypersurfaces in toric 3-folds
We show that the usual sufficient criterion for a generic hypersurface in a
smooth projective manifold to have the same Picard number as the ambient
variety can be generalized to hypersurfaces in complete simplicial toric
varieties. This sufficient condition is always satisfied by generic K3 surfaces
embedded in Fano toric 3-folds.Comment: 14 pages. v2: some typos corrected. v3: Slightly changed title. Final
version to appear in Int. J. Math., incorporates many (mainly expository)
changes suggested by the refere
Distribution of chirality in the quantum walk: Markov process and entanglement
The asymptotic behavior of the quantum walk on the line is investigated
focusing on the probability distribution of chirality independently of
position. The long-time limit of this distribution is shown to exist and to
depend on the initial conditions, and it also determines the asymptotic value
of the entanglement between the coin and the position. It is shown that for
given asymptotic values of both the entanglement and the chirality distribution
it is possible to find the corresponding initial conditions within a particular
class of spatially extended Gaussian distributions. Moreover it is shown that
the entanglement also measures the degree of Markovian randomness of the
distribution of chirality.Comment: 5 pages, 3 figures, It was accepted in Physcial Review
Preferential associated anomalies in 818 cases of microtia in South america
The etiology of microtia remains unknown in most cases. The identification of patterns of associated anomalies (i.e., other anomalies that occur with a given congenital anomaly in a higher than expected frequency), is a methodology that has been used for research into the etiology of birth defects. We conducted a study based on cases of microtia that were diagnosed from more than 5 million live (LB)- and stillbirths (SB) examined in hospitals participating in ECLAMC (Latin American Collaborative Study of Congenital Malformations) between 1967 and 2009. We identified 818 LB and SB with microtia and at least one additional non-related major congenital anomaly (cases) and 15,969 LB and SB with two or more unrelated major congenital anomalies except microtia (controls). A logistic regression analysis was performed to identify the congenital anomalies preferentially associated with microtia. Preferential associations were observed for 10 congenital anomalies, most of them in the craniofacial region, including facial asymmetry, choanal atresia, and eyelid colobomata. The analysis by type of microtia showed that for anomalies such as cleft lip and palate, macrostomia, and limb reduction defects, the frequency increased with the severity of the microtia. In contrast, for other anomalies the frequency tended to be the same across all types of microtia. Based on these results we will integrate data on the developmental pathways related to preferentially associated congenital anomalies for future studies investigating the etiology of microtia.Fil: Luquetti, Daniela V.. University of Washington; Estados Unidos. Seattle Children’s Research Institute; Estados UnidosFil: Cox, Thimoty C.. Monash University; Australia. University of Washington; Estados UnidosFil: López Camelo, Jorge Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET.; ArgentinaFil: Dutra, Maria da Graça. Instituto Oswaldo Cruz; BrasilFil: Cunningham, Michael L.. University of Washington; Estados Unidos. Seattle Children’s Research Institute; Estados UnidosFil: Castilla, Eduardo Enrique. Centro de Educación Médica e Investigaciones Clínicas “Norberto Quirno”; Argentina. Instituto Oswaldo Cruz; Brasil. Instituto Nacional de Genética Médica Populacional; Brasi
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