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Towton, 1461: An integrated approach to battlefield archaeology
Ye
Transient dynamics of a molecular quantum dot with a vibrational degree of freedom
We investigate the transient effects occurring in a molecular quantum dot
described by an Anderson-Holstein Hamiltonian which is instantly coupled to two
fermionic leads biased by a finite voltage. In the limit of weak
electron-phonon interaction, we use perturbation theory to determine the
time-dependence of the dot population and the average current. The limit of
strong coupling is accessed by means of a self-consistent time-dependent
mean-field approximation. These comple- mentary approaches allow us to
investigate the dynamics of the inelastic effects occurring when the applied
bias voltage exceeds the phonon frequency and the emergence of bistability.Comment: 7 pages, 4 figure
Variable-beamwidth antenna without moving parts
Basic configuration consists of large parabolic dish reflector, smaller hyperboloidal subreflector, and two sets of monopulse feeds located in conjugate focal region on boresight axis of dish
Cluster: A fleet of four spacecraft to study plasma structures in three dimensions
The four Cluster spacecraft are spin stabilized spacecraft which are designed and built under stringent requirements as far as electromagnetic cleanliness is concerned. Conductive surfaces and low electromagnetic background noise are mandatory for accurate electric field and cold plasma measurements. The mission is implemented in collaboration between ESA and NASA. A Russian mission will be closely coordinated with Cluster
Quick-disconnect coupling safe transfer of hazardous fluids
Quick-disconnect coupling is used for uncoupling of plumbing during ground-to-vehicle transfer of cryogenic and hazardous fluids. The coupling allows remote positive control of liquid pressure and flow during the transfer operation, remote connection and separation capabilities, and negligible liquid spillage upon disconnection
Navigation systems for approach and landing of VTOL aircraft
The formulation and implementation of navigation systems used for research investigations in the V/STOLAND avionics system are described. The navigation systems prove position and velocity in a cartestian reference frame aligned with the runway. They use filtering techniques to combine the raw position data from navaids (e.g., TACAN, MLS) with data from onboard inertial sensors. The filtering techniques which use both complementary and Kalman filters, are described. The software for the navigation systems is also described
A Low Cost and Labor Efficient Method for Rearing Black Cutworms (Lepidoptera: Noctuidae)
The black cutworm, Agrotis ipsilon (Hufnagel), has been and continues to be the subject of many biological and control studies in the north-central states. Interest in this insect can often be traced to its status as a major, but sporadic pest of field com in the region
Simulation and theory of fluid demixing and interfacial tension of mixtures of colloids and non-ideal polymers
An extension of the Asakura-Oosawa-Vrij model of hard sphere colloids and
non-adsorbing polymers, that takes polymer non-ideality into account through a
repulsive stepfunction pair potential between polymers, is studied with grand
canonical Monte Carlo simulations and density functional theory. Simulation
results validate previous theoretical findings for the shift of the bulk fluid
demixing binodal upon increasing strength of polymer-polymer repulsion,
promoting the tendency to mix. For increasing strength of the polymer-polymer
repulsion, simulation and theory consistently predict the interfacial tension
of the free colloidal liquid-gas interface to decrease significantly for fixed
colloid density difference in the coexisting phases, and to increase for fixed
polymer reservoir packing fraction.Comment: 10 pages, 4 figure
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