17,384 research outputs found
Synthetic aperture radar operator tactical target acquisition research
A radar target acquisition research study was conducted to access the effects of two levels of 13 radar sensor, display, and mission parameters on operator tactical target acquisition. A saturated fractional-factorial screening design was employed to examine these parameters. Data analysis computed ETA squared values for main and second-order effects for the variables tested. Ranking of the research parameters in terms of importance to system design revealed four variables (radar coverage, radar resolution/multiple looks, display resolution, and display size) accounted for 50 percent of the target acquisition probability variance
Coarse-grained interaction potentials for polyaromatic hydrocarbons
Using Kohn-Sham density functional theory (KS-DFT), we have studied the
interaction between various polyaromatic hydrocarbon molecules. The systems
range from mono-cyclic benzene up to hexabenzocoronene (hbc). For several
conventional exchange-correlation functionals potential energy curves of
interaction of the - stacking hbc dimer are reported. It is found
that all pure local density or generalized gradient approximated functionals
yield qualitatively incorrect predictions regarding structure and interaction.
Inclusion of a non-local, atom-centered correction to the KS-Hamiltonian
enables quantitative predictions. The computed potential energy surfaces of
interaction yield parameters for a coarse-grained potential, which can be
employed to study discotic liquid-crystalline mesophases of derived
polyaromatic macromolecules
RISK AND RETURN TO IP GRAIN PRODUCTION: THE CASE OF HIGH OIL CORN
Returns for soybeans, commodity corn and high oil corn under an export and domestic market buyer's-call contract were simulated. High oil corn is competitive with commodity corn when yield drag is two percent and bundling reduces seed cost. Commodity loan rate is important in reducing high oil corn price risk.Crop Production/Industries,
Multi-mode coupling wave theory for helically corrugated waveguide
Helically corrugated waveguide has been used in various applications such as gyro-backward wave oscillators, gyro-traveling wave amplifier and microwave pulse compressor. A fast prediction of the dispersion characteristic of the operating eigenwave is very important when designing a helically corrugated waveguide. In this paper, multi-mode coupling wave equations were developed based on the perturbation method. This method was then used to analyze a five-fold helically corrugated waveguide used for X-band microwave compression. The calculated result from this analysis was found to be in excellent agreement with the results from numerical simulation using CST Microwave Studio and vector network analyzer measurements
Quantum channels in nonlinear optical processes
Quantum electrodynamics furnishes a new type of representation for the characterisation of nonlinear optical processes. The treatment elicits the detailed role and interplay of specific quantum channels, information that is not afforded by other methods. Following an illustrative application to the case of Rayleigh scattering, the method is applied to second and third harmonic generation. Derivations are given of parameters that quantify the various quantum channels and their interferences; the results are illustrated graphically. With given examples, it is shown in some systems that optical nonlinearity owes its origin to an isolated channel, or a small group of channels. © 2009 World Scientific Publishing Company
Electric field control and optical signature of entanglement in quantum dot molecules
The degree of entanglement of an electron with a hole in a vertically coupled
self-assembled dot molecule is shown to be tunable by an external electric
field. Using atomistic pseudopotential calculations followed by a configuration
interaction many-body treatment of correlations, we calculate the electronic
states, degree of entanglement and optical absorption. We offer a novel way to
spectroscopically detect the magnitude of electric field needed to maximize the
entanglement.Comment: 4 pages, 6 figure
Phase 1 Trial of Vaccination with Autologous Tumor Cells and Antisense Directed Against the Insulin Growth Factor Type 1 Receptor (IGF-1R AS ODN) in Patients with Recurrent Glioblastoma
Background: Extending a previous Phase I study, we report the results of a second Phase I autologous tumor cell vaccination trial for patients with recurrent glioblastomas (IND 14379-101, NCT01550523).
Methods: Following surgery, subjects were treated by 24 hour implantation in the rectus sheath of ten biodiffusion chambers containing irradiated autologous tumor cells and IGF-1R AS ODN with the objective of stimulating tumor immunity. Patients were monitored for safety, clinical and radiographic as well as immune responses.
Results: There were no Grade 3 toxicities related to protocol treatment and overall median survival from initial diagnosis was 91.4 weeks. Two protocol survival cohorts with median survivals of 48.2 and 10 weeks were identified and predicted by our pre-treatment assessments of immune function, corroborated by post-vaccination pro-inflammatory cytokine profiles. Longer survival subjects had imaging findings including transient elevations in cerebral blood volume (rCBV) and sustained elevations of apparent diffusion coefficient (ADC) interpreted as transient hyperemia and cell loss.
Conclusions: The vaccine paradigm was well-tolerated with a favorable median survival. Our data support this as a novel treatment paradigm that promotes anti-tumor immunity
Time-dependent Maxwell field operators and field energy density for an atom near a conducting wall
We consider the time evolution of the electric and magnetic field operators
for a two-level atom, interacting with the electromagnetic field, placed near
an infinite perfectly conducting wall. We solve iteratively the Heisenberg
equations for the field operators and obtain the electric and magnetic energy
density operators around the atom (valid for any initial state). Then we
explicitly evaluate them for an initial state with the atom in its bare ground
state and the field in the vacuum state. We show that the results can be
physically interpreted as the superposition of the fields propagating directly
from the atom and the fields reflected on the wall. Relativistic causality in
the field propagation is discussed. Finally we apply these results to the
calculation of the dynamical Casimir-Polder interaction energy in the far zone
between two atoms when a boundary condition such as a conducting wall is
present. Magnetic contributions to the interatomic Casimir-Polder interaction
in the presence of the wall are also considered. We show that, in the limit of
large times, the known results of the stationary case are recovered.Comment: 11 page
Contributions to the Science of Environmental Impact Assessment: Three Papers on the Arctic Cisco (Coregonus autumnalis) of Northern Alaska
Editor's Introduction -- D. W. Norton; An Assessment of the Colville River Delta Stock of Arctic Cisco--Migrants from Canada? -- B. J. Gallaway, W. B. Griffiths, P. C. Craig, W. J. Gazey, and J. W. Helmericks; Temperature Preference of Juvenile Arctic Cisco (Coregonus autumnalis) From the Alaskan Beaufort Sea -- R. G. Fechhelm, W. H. Neill, and B. J. Gallaway; Modeling Movements and Distribution of Arctic Cisco (Coregonus autumnalis) Relative to Temperature-Salinity Regimes of the Beaufort Sea Near the Waterflood Causeway, Prudhoe Bay, Alaska. -- W. H. Neill, R. G. Fechhelm, B. J. Gallaway, J. D. Bryan, and S. W. Anderson; Notice to Author
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