11,320 research outputs found
Hydrologic Investigations of Small Watersheds in Ohio: Terminal Report Phase I: 1966-1969
(print) iii, 69 p. : ill., maps ; 28 cm.Traditional statistical, analytical techniques and deterministic models
were used to study runoff phenomena from agricultural and strip-mined areas at the North Appalachia Experimental Watersheds Station near Coshocton, Ohio. Agricultural land use and surface strip mining were found to influence the hydrology of the watershed and the physical and chemical quality of the
runoff water. Peak runoff rates were predicted using the standard formulas
and with the Stanford and Purdue computer models. The latter were modified and input parameters had to be developed before using them. A basic study to better understand the fundamental phenomena and the mechanics of runoff were studied. Small watersheds were defined as watersheds whose hydrology
is modified with agricultural and industrial practices on the land during a year's time.Foreword -- Introduction -- General Description of the Study Area -- The Influence of Land Use and Treatment on the Hydrology of Small Watersheds -- Instrumentation of a Strip-Mine Study Area for Hydrologic Investigations -- Applicability of Runoff Formulas to Coshocton Watershed -- Application of the Stanford Streamflow Similation Model to Agricultural Watersheds -- A Stochastic Approach to Overland Flow -- Runoff Simulation with a Model Developed by Huggins and Monke -- Reference
The integrability of Lie-invariant geometric objects generated by ideals in the Grassmann algebra
We investigate closed ideals in the Grassmann algebra serving as bases of
Lie-invariant geometric objects studied before by E. Cartan. Especially, the E.
Cartan theory is enlarged for Lax integrable nonlinear dynamical systems to be
treated in the frame work of the Wahlquist Estabrook prolongation structures on
jet-manifolds and Cartan-Ehresmann connection theory on fibered spaces. General
structure of integrable one-forms augmenting the two-forms associated with a
closed ideal in the Grassmann algebra is studied in great detail. An effective
Maurer-Cartan one-forms construction is suggested that is very useful for
applications. As an example of application the developed Lie-invariant
geometric object theory for the Burgers nonlinear dynamical system is
considered having given rise to finding an explicit form of the associated Lax
type representation
Perbedaan Kompetensi Sosial Anak Berdasarkan Tipe Pendidikan Prasekolah
Penelitian ini bertujuan untuk mengetahui peran tipe pendidikan prasekolah dalam kompetensi sosial anak. Dua hipotesis diajukan untuk menguji perbedaan kompetensi sosial anak dengan tipe pendidikan prasekolah penuh waktu dan paruh waktu. Subjek penelitian ini adalah 209 orang anak usia lima sampai dengan enam tahun yang mengikuti salah satu tipe pendidikan prasekolah (paruh waktu atau penuh waktu) yang berasal dari enam Taman Kanak-kanak di Yogyakarta (Budi Mulia I Kaliurang, Primagama Kaliurang, ABA Purwodiningratan, Nurul Islam Ringroad Barat, BIAS Kaliurang, dan Budi Mulia Dua Seturan). Data penelitian diperoleh dengan menggunaka skala kompetensi sosial, kuesioner keluarga dan dokumentasi sekolah. Skala kompetensi sosial dinilai oleh guru kelas dengan menggunakan teknik interrater. Jumlah item pada skala kompetensi sosial adalah 30 item. Setelah uji coba terdapat 4 item yang gugur. Daya beda item berkisar dari 0,303-0,581 dengan angka reliabilitas 0,890. Sedangkan nilai reliabilitas antar rater berkisar antara 0,867-0,998. Hasil ANCOVA, diperoleh kesimpulan hasil penelitian bahwa: (1) ada perbedaan kompetensi sosial anak dengan tipe pendidikan prasekolah paruh waktu dan penuh waktu. Kompetensi sosial anak dengan tipe pendidikan prasekolah penuh waktu lebih tinggi daripada kompetensi sosial anak dengan tipe pendidikan prasekolah paruh waktu (F = 21,612; p = 0,000). (2) tidak ada korelasi antara kompetensi sosial anak yang berusia lima tahun sampai dengan enam tahun (F = 1,781; p = 0,184)
Lie group analysis of a generalized Krichever-Novikov differential-difference equation
The symmetry algebra of the differential--difference equation
where , and are arbitrary analytic functions is shown to have the
dimension 1 \le \mbox{dim}L \le 5. When , and are specific second
order polynomials in (depending on 6 constants) this is the integrable
discretization of the Krichever--Novikov equation. We find 3 cases when the
arbitrary functions are not polynomials and the symmetry algebra satisfies
\mbox{dim}L=2. These cases are shown not to be integrable. The symmetry
algebras are used to reduce the equations to purely difference ones. The
symmetry group is also used to impose periodicity and thus to
reduce the differential--difference equation to a system of coupled
ordinary three points difference equations
Gradient catastrophe and flutter in vortex filament dynamics
Gradient catastrophe and flutter instability in the motion of vortex filament
within the localized induction approximation are analyzed. It is shown that the
origin if this phenomenon is in the gradient catastrophe for the dispersionless
Da Rios system which describes motion of filament with slow varying curvature
and torsion. Geometrically this catastrophe manifests as a rapid oscillation of
a filament curve in a point that resembles the flutter of airfoils.
Analytically it is the elliptic umbilic singularity in the terminology of the
catastrophe theory. It is demonstrated that its double scaling regularization
is governed by the Painlev\'e-I equation.Comment: 11 pages, 3 figures, typos corrected, references adde
Stability of vortices in rotating taps: a 3d analysis
We study the stability of vortex-lines in trapped dilute gases subject to
rotation. We solve numerically both the Gross-Pitaevskii and the Bogoliubov
equations for a 3d condensate in spherically and cilyndrically symmetric
stationary traps, from small to very large nonlinearities. In the stationary
case it is found that the vortex states with unit and charge are
energetically unstable. In the rotating trap it is found that this energetic
instability may only be suppressed for the vortex-line, and that the
multicharged vortices are never a local minimum of the energy functional, which
implies that the absolute minimum of the energy is not an eigenstate of the
operator, when the angular speed is above a certain value, .Comment: 10 pages, 7 figures in EPS forma
Physical properties of fullerene-containing Galactic planetary nebulae
We searched the Spitzer Space Telescope data archive for Galactic planetary nebulae (PNe), which show the characteristic 17.4 and 18.9 µm features due to C60, also known as buckminsterfullerene. Out of 338 objects with Spitzer/Infrared Spectrograph data, we found eleven C60-containing PNe, six of which (Hen2-68, IC2501, K3-62, M1-6, M1-9 and SaSt2-3) are new detections, not known to contain C60 prior to this work. The strongest 17.4 and 18.9 µm C60 features are seen in Tc1 and SaSt2-3, and these two sources also prominently show the C60 resonances at 7.0 and 8.5 µm. In the other nine sources, the 7.0 and 8.5 µm features due to C60 are much weaker. We analysed the spectra, along with ancillary data, using the photoionization code CLOUDY to establish the atomic line fluxes, and determine the properties of the radiation field, as set by the effective temperature of the central star. In addition, we measured the infrared spectral features due to dust grains. We find that the polycyclic aromatic hydrocarbon (PAH) profile over 6–9 µm in these C60-bearing carbon-rich PNe is of the more chemically processed class A. The intensity ratio of 3.3 to 11.3 µm PAH indicates that the number of C-atoms per PAH in C60-containing PNe is small compared to that in non-C60 PNe. The Spitzer spectra also show broad dust features around 11 and 30 µm. Analysis of the 30 µm feature shows that it is strongly correlated with the continuum, and we propose that a single carbon-based carrier is responsible for both the continuum and the feature. The strength of the 11 µm feature is correlated to the temperature of the dust, suggesting that it is at least partially due to a solid-state carrier. The chemical abundances of C60-containing PNe can be explained by asymptotic giant branch nucleosynthesis models for initially 1.5–2.5 M⊙ stars with Z = 0.004. We plotted the locations of C60-containing PNe on a face-on map of the Milky Way and we found that most of these PNe are outside the solar circle, consistent with low metallicity values. Their metallicity suggests that the progenitors are an older population
Fat Mass and Obesity-Associated Gene (FTO) in Eating Disorders: Evidence for Association of the rs9939609 Obesity Risk Allele with Bulimia nervosa and Anorexia nervosa
Objective: The common single nucleotide polymorphism (SNP) rs9939609 in the fat mass and obesity-associated gene (FTO) is associated with obesity. As genetic variants associated with weight regulation might also be implicated in the etiology of eating disorders, we evaluated whether SNP rs9939609 is associated with bulimia nervosa (BN) and anorexia nervosa (AN). Methods: Association of rs9939609 with BN and AN was assessed in 689 patients with AN, 477 patients with BN, 984 healthy non-population-based controls, and 3,951 population-based controls (KORA-S4). Based on the familial and premorbid occurrence of obesity in patients with BN, we hypothesized an association of the obesity risk A-allele with BN. Results: In accordance with our hypothesis, we observed evidence for association of the rs9939609 A-allele with BN when compared to the non-population-based controls (unadjusted odds ratio (OR) = 1.142, one-sided 95% confidence interval (CI) 1.001-infinity; one-sided p = 0.049) and a trend in the population-based controls (OR = 1.124, one-sided 95% CI 0.932-infinity; one-sided p = 0.056). Interestingly, compared to both control groups, we further detected a nominal association of the rs9939609 A-allele to AN (OR = 1.181, 95% CI 1.027-1.359, two-sided p = 0.020 or OR = 1.673, 95% CI 1.101-2.541, two-sided p = 0.015,). Conclusion: Our data suggest that the obesity-predisposing FTO allele might be relevant in both AN and BN. Copyright (C) 2012 S. Karger GmbH, Freibur
The on-ground calibration of the flight model of the HPGSPC onboard the SAX satellite: Calibration set-up and preliminary results
The High Pressure Gas Scintillation Proportional Counter (HPGSPC) is one of the Narrow Field Instruments of the Italian-Dutch X-ray astronomy satellite SAX. Sensitive in the hard X-ray band (4–120 keV), with a very good energy
resolution, the HPGSPC is well suited for studying in detail the cyclotron features present in the hard X-ray spectrum of some celestial sources. The scientific
calibration of the flight model of the HPGSPC took place at the LABEN premises(Vimodrone-Milano) during October and November 1994. In this paper we briefly describe the
on-ground instrument calibration system and we report some
preliminary results that show the performances of both single/double event and position reconstruction/energy correction onboard processing. Preliminary results
concerning the energy resolution and energy linearity are reported too
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