5,228 research outputs found
Results of a 0.03- scale aerodynamic characteristics investigation of Boeing 747 carrier (model no. AX 1319 I-1) mated with a space shuttle orbiter (model 45-0) conducted in the Boeing transonic wind tunnel (CA5), volume 1
The performance, stability, and control characteristics of various carrier aircraft configurations are presented. Aerodynamic characteristics of the carrier mated with the Orbiter, carrier alone, and Orbiter alone were investigated. Carrier support system tare and interference effects were determined. Six-component force and moment data were recorded for the carrier and Orbiter. Buffet onset characteristics of the carrier vertical tail and horizontal tail were recorded. Angles of attack from -3 deg through 26 deg and angles of slideslip between +12 deg and -12 deg were investigated at Mach numbers from 0.15 through 0.70. Photographs are included
Structure and dielectric properties of polar fluids with extended dipoles: results from numerical simulations
The strengths and short-comings of the point-dipole model for polar fluids of
spherical molecules are illustrated by considering the physically more relevant
case of extended dipoles formed by two opposite charges separated by a
distance (dipole moment ). Extensive Molecular Dynamics
simulations on a high density dipolar fluid are used to analyse the dependence
of the pair structure, dielectric constant \eps and dynamics as a function of
the ratio (\sig is the molecular diameter), for a fixed dipole
moment . The point dipole model is found to agree well with the extended
dipole model up to d/\sig \simeq 0.3. Beyond that ratio, \eps shows a
non-trivial variation with d/\sig. When d/\sig>0.6, a transition is
observed towards a hexagonal columnar phase; the corresponding value of the
dipole moment, \mu^2/\sig^3 k T=3, is found to be substantially lower than
the value of the point dipole required to drive a similar transition.Comment: 10 pages, 11 figures; Paper submitted to Molecular Physic
Anharmonicity and self-similarity of the free energy landscape of protein G
The near-native free energy landscape of protein G is investigated through
0.4 microseconds-long atomistic molecular dynamics simulations in explicit
solvent. A theoretical and computational framework is used to assess the
time-dependence of salient thermodynamical features. While the quasi-harmonic
character of the free energy is found to degrade in a few ns, the slow modes
display a very mild dependence on the trajectory duration. This property
originates from a striking self-similarity of the free energy landscape
embodied by the consistency of the principal directions of the local minima,
where the system dwells for several ns, and of the virtual jumps connecting
them.Comment: revtex, 6 pages, 5 figure
Time Preferences and Criminal Behavior
One main motive behind lengthy prison terms for serious crime is to deter potential offenders from engaging in crime. Yet, economic theory predicts that the scope for punishment as acting as a deterrent depends on how much individuals discount future events when balancing the immediate utility of the crime and the costs of a potential future punishment. If criminals have short time horizons, then it is hard to imagine punishment acting as a key deterrent. This paper provides the first empirical investigation of the link between time preferences and criminal behavior. Our study is made possible by access to a unique Swedish longitudinal dataset that links individual measures of time preferences collected at age 13 to various crime indicators from administrative registers spanning over 18 years. Our results show that high discount rates significantly predict criminal involvement. The magnitude of the relationship is substantial and corresponds to roughly one third of the association between intelligence and crime. Although high discount rates significantly predict the onset of criminal involvement, it is less strongly correlated with crime at the intensive margin. The link is more pronounced for property crime and among males with low intelligence. We also find that part of the association can be explained by high discount rates being associated with lower human capital accumulation
Shuttle model tailcone pressure distribution at low subsonic speeds of a 0.03614-scale model in the NASA/LaRC low-turbulence pressure tunnel (LA81), volume 1
An investigation was conducted in the NASA/LaRC Low-Turbulence Pressure Tunnel on a 0.03614-scale orbiter model of a 089B configuration with a 139B configuration nose forward of F.S. 500. The tailcone was the TC sub 4 design and was instrumented with eighty-nine pressure orifices. Control surfaces were deflected and three wind tunnel mounting techniques were investigated over an angle-of-attack range from -2 deg to a maximum of 18 deg. In order to determine the sensitivity of the tailcone to changes in Reynolds number, most of the test was made at a Mach number of 0.20 over a Reynolds number range of 2.0 to 10 million per foot. A few runs were made at a Mach number of 0.30 at Reynolds numbers of 4.0, 6.0, and 8 million per foot
Shuttle model tailcone pressure distribution at low subsonic speeds of a 0.03614-scale model in the NASA/LaRC low-turbulence pressure tunnel (LA81), volume 2
For abstract, see Vol 1
Upper wing surface boundary layer measurements and static aerodynamic data obtained on a 0.015-scale model (42-0) or the SSV orbiter configuration 140A/B in the LTV HSWT at a Mach number of 4.6 (LA58)
The purpose of the test was to investigate the nature of the Orbiter boundary layer characteristics at angles of attack from -4 to 32 degrees at a Mach number of 4.6. The effect of large grit, employed as transition strips, on both the nature of the boundary layer and the force and moment characteristics were investigated along with the effects of large negative elevon deflection on lee side separation. In addition, laminar and turbulent boundary layer separation phenomena which could cause asymmetric flow separation were investigated
Metastability of life
The physical idea of the natural origin of diseases and deaths has been
presented. The fundamental microscopical reason is the destruction of any
metastable state by thermal activation of a nucleus of a nonreversable change.
On the basis of this idea the quantitative theory of age dependence of death
probability has been constructed. The obtained simple Death Laws are very
accurately fulfilled almost for all known diseases.Comment: 3 pages, 4 figure
Results of a 0.03-scale aerodynamic characteristics investigation of a Boeing 747 carrier (model no. AX 1319 I-1) mated with a space shuttle orbiter (model 45-0) conducted in the Boeing transonic wind tunnel (CA5), volume 2
For abstract, see N75-33162
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