32,469 research outputs found
Flood Frequency Design in Sparse-data Regions
Project Completion Report OWRT Contract No. 14-31-0001-5217 Grant No. B-030-ALASThis report summarizes work conducted with funds received from the Office of Water Research and Technology (OWRT), Project B-030-ALAS, Flood Frequency in Sparse-Data Regions. The study was conducted from July 1, 1974, to June 30, 1976, plus a one-year extension to June 30, 1977. The technical results are given in a number of publications which are referenced and abstracted here along with a presentation of the overall philosophy of the project and a coherent summary of the work. Alaska may be characterized, as can most northern areas, by a very sparse data collection network of hydrologic variables. In combination with several physical characteristics of northern hydrology, the sparse data network leads to a very difficult design circumstance. The most well known physical aspect of northern hydrology is permafrost. Other factors of importance are large elevation differences, regional inhomogeneity, high latitude, low temperatures, and the very dynamic nature of the spring breakup. These factors, in combination with the short data base in northern regions, cause hydrologic design to have a large degree of uncertainty.The work upon which this completion report is based was supported by funds provided by the U. S. Department of the Interior, Office of Water Research and Technology, as authorized under the Water Resources Research Act of 1964, Public Law 88-379, as amended
Development of an Operational Northern Aquatic Ecosystem Model: Completion Report
OWRR Contract No. 14-31-0001-5217 Grant No. C-6169The work upon which this completion report is based was supported
by funds provided by the U. S. Department of the Interior, Office of
Water Research and Technology as authorized under the Water Resources
Research Act of 1964, Public Law 88-379, as amended
In situ analysis for intelligent control
We report a pilot study on in situ analysis of backscatter data for intelligent control of a scientific instrument on an Autonomous Underwater Vehicle (AUV) carried out at the Monterey Bay Aquarium Research Institute (MBARI). The objective of the study is to investigate techniques which use machine intelligence to enable event-response scenarios. Specifically we analyse a set of techniques for automated sample acquisition in the water-column using an electro-mechanical "Gulper", designed at MBARI. This is a syringe-like sampling device, carried onboard an AUV. The techniques we use in this study are clustering algorithms, intended to identify the important distinguishing characteristics of bodies of points within a data sample. We demonstrate that the complementary features of two clustering approaches can offer robust identification of interesting features in the water-column, which, in turn, can support automatic event-response control in the use of the Gulper
Incidence of Obesity Among Mentally Retarded Children
An international survey of professionals in the field of mental retardation was conducted to determine significant research priorities in the education of students with mild retardation. A total of 67 individuals responded to survey which represented 83.7% of those contacted. Among the issues rated most highly were two clusters: vocational, career education and post-school adjustment and long term effects and generalization of effects of programs. Implications of the survey data are discussed and recommendations are provided
Symmetry breaking in MAST plasma turbulence due to toroidal flow shear
The flow shear associated with the differential toroidal rotation of tokamak
plasmas breaks an underlying symmetry of the turbulent fluctuations imposed by
the up-down symmetry of the magnetic equilibrium. Using experimental
Beam-Emission-Spectroscopy (BES) measurements and gyrokinetic simulations, this
symmetry breaking in ion-scale turbulence in MAST is shown to manifest itself
as a tilt of the spatial correlation function and a finite skew in the
distribution of the fluctuating density field. The tilt is a statistical
expression of the "shearing" of the turbulent structures by the mean flow. The
skewness of the distribution is related to the emergence of long-lived density
structures in sheared, near-marginal plasma turbulence. The extent to which
these effects are pronounced is argued (with the aid of the simulations) to
depend on the distance from the nonlinear stability threshold. Away from the
threshold, the symmetry is effectively restored
Reformulation in planning
Reformulation of a problem is intended to make the problem more amenable to efficient solution. This is equally true in the special case of reformulating a planning problem. This paper considers various ways in which reformulation can be exploited in planning
Multi-filter transit observations of WASP-39b and WASP-43b with three San Pedro M\'artir telescopes
Three optical telescopes located at the San Pedro M\'artir National
Observatory were used for the first time to obtain multi-filter defocused
photometry of the transiting extrasolar planets WASP-39b and WASP-43b. We
observed WASP-39b with the 2.12m telescope in the U filter for the first time,
and additional observations were carried out in the R and I filters using the
0.84m telescope. WASP-43b was observed in VRI with the same instrument, and in
the i filter with the robotic 1.50m telescope. We reduced the data using
different pipelines and performed aperture photometry with the help of custom
routines, in order to obtain the light curves. The fit of the light curves
(1.5--2.5mmag rms), and of the period analysis, allowed a revision of the
orbital and physical parameters, revealing for WASP-39b a period ( days) which is seconds larger than
previously reported. Moreover, we find for WASP-43b a planet/star radius
() which is larger in the i filter
with respect to previous works, and that should be confirmed with additional
observations. Finally, we confirm no evidence of constant period variations in
WASP-43b.Comment: 13 pages, 7 figures, accepted in PASP, scheduled for the February 1,
2015 issu
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