5,316 research outputs found
The Use of Wheel Brakes on Airplanes
The results of tests to determine the effect of wheel brakes on the landing run of an airplane under conditions of load and at various wind velocities are presented
The sciences in America, circa 1880
For many years American science in the late 19th century was regarded as an intellectual backwater. This view derived from the assumption that the health of American science at the time was equivalent to the condition of pure science, especially pure physics. However, a closer look reveals that there was considerable vitality in American scientific research, especially in the earth and life sciences. This vitality is explainable in part by the natural scientific resources of the American continent but also in part by the energy given science from religious impulses, social reformism, and practicality. Furthermore, contrary to recent assumptions, the federal government was a significant patron of American science. The portrait of American science circa 1880 advanced in this article suggests that the nation's scientific enterprise was characterized by pluralism of institutional support and motive and that such pluralism has historically been the normal mode
An analysis of the relationship between funding levels and expenditure patterns in New Hampshire high schools, 1985-1986 to 1993-1994
The purpose of this research was to determine if there was a relationship between the level of funds available and the pattern of expenditure in New Hampshire high schools. For example, was there a relationship between the percentage of its budget a high school spends on regular education programs and its overall per pupil cost? The hypothesis was that there would be less than a moderate correlation between each of eight variables and per pupil expenditure. A Pearson r value of 0.30 or greater was defined as indicating a moderate correlation.
The study also examined each high school\u27s spending pattern over time to determine if there was a change in the pattern of expenditure. The hypothesis was that there would be only small changes in expenditure patterns. Finally, the study examined the expenditure pattern of the 38 high schools taken as a group to determine if the pattern of spending across the state was the same. This was examined for each year and for the total time period examined. The hypothesis was that there would only be small differences in expenditure patterns across the 38 schools and only small changes over the nine year period. A coefficient of variation of 0.10 or less was used to define a small change.
The research examined four different expenditure areas: (a) regular education, (b) guidance services, (c) educational media and (d) school administration. The amount of money expended in each area was broken down into personnel costs and the cost of supplies and materials.
The data supported the following conclusions: (1) There was a negative correlation between regular education expenditures and per pupil cost, in some cases this correlation reached the moderate level. (2) There was a positive correlation between guidance personnel spending and per pupil cost. (3) While there was a consistent pattern of expenditure within individual schools there was not a consistent pattern across schools. (4) The 38 schools, taken as a group, had a consistent expenditure pattern during the period covered by the study
The Radius of the Proton: Size Does Matter
The measurement by Pohl et al. [1] of the 2S_1/2^F=1 to 2P_3/2^F=2 transition
in muonic hydrogen and the subsequent analysis has led to a conclusion that the
rms charge radius of the proton differs from the accepted (CODATA [2]) value by
approximately 4%, leading to a 4.9 s.d. discrepancy. We investigate the muonic
hydrogen spectrum relevant to this transition using bound-state QED with Dirac
wave-functions and comment on the extent to which the perturbation-theory
analysis which leads to the above conclusion can be confirmed.Comment: Delayed arXiv submission. To appear in 'Proceedings of T(R)OPICALQCD
2010' (September 26 - October 1, 2010). 7 pages, 1 figure. Superseded by
arXiv:1104.297
Neutron Star Properties with Hyperons
In the light of the recent discovery of a neutron star with a mass accurately
determined to be almost two solar masses, it has been suggested that hyperons
cannot play a role in the equation of state of dense matter in
-equilibrium. We re-examine this issue in the most recent development of
the quark-meson coupling model. Within a relativistic Hartree-Fock approach and
including the full tensor structure at the vector-meson-baryon vertices, we
find that not only must hyperons appear in matter at the densities relevant to
such a massive star but that the maximum mass predicted is completely
consistent with the observation.Comment: Minor correction
The construction and evaluation of an instrument to determine the sports knowledge of boys from grades nine through twelve,
Thesis (M.A.)--Boston Universit
Many-Body Interactions in a Sample of Ultracold Rydberg Atoms with Varying Dimensions and Densities
Ultracold highly excited atoms in a magneto-optical trap (MOT) are strongly coupled by the dipole-dipole interaction. We have investigated the importance of many-body effects by controlling the dimensionality and density of the excited sample. We excited three different cylindrical volumes of atoms in the MOT to Rydberg states. At small radius, where the sample is nearly one-dimensional, many-body interactions are suppressed. At larger radii, the sample becomes three-dimensional and many-body effects are apparent
Phase transition from quark-meson coupling hyperonic matter to deconfined quark matter
We investigate the possibility and consequences of phase transitions from an
equation of state (EOS) describing nucleons and hyperons interacting via mean
fields of sigma, omega, and rho mesons in the recently improved quark-meson
coupling (QMC) model to an EOS describing a Fermi gas of quarks in an MIT bag.
The transition to a mixed phase of baryons and deconfined quarks, and
subsequently to a pure deconfined quark phase, is described using the method of
Glendenning. The overall EOS for the three phases is calculated for various
scenarios and used to calculate stellar solutions using the
Tolman-Oppenheimer-Volkoff equations. The results are compared with recent
experimental data, and the validity of each case is discussed with consequences
for determining the species content of the interior of neutron stars.Comment: 12 pages, 14 figures; minor typos correcte
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