20,772 research outputs found
Analysis of pressure distortion testing
The development of a distortion methodology, method D, was documented, and its application to steady state and unsteady data was demonstrated. Three methodologies based upon DIDENT, a NASA-LeRC distortion methodology based upon the parallel compressor model, were investigated by applying them to a set of steady state data. The best formulation was then applied to an independent data set. The good correlation achieved with this data set showed that method E, one of the above methodologies, is a viable concept. Unsteady data were analyzed by using the method E methodology. This analysis pointed out that the method E sensitivities are functions of pressure defect level as well as corrected speed and pattern
The collection and preservation of insects
INSECTS may be collected with the aid of a collecting-net or a suction-tube and killed in an appropriate bottle containing a killing agent. The insects are then pinned and mounted on a spreading-board. When the specimens are dry they are removed from the board, suitably labelled, and put away in a store box. Certain insects which cannot be mounted immediately after collection are relaxed in moist jars. Larval and pupal stages are stored in labelled tubes containing alcohol
Observations on the Overwintering Potential of the Striped Cucumber Beetle (Coleoptera: Chrysomelidae) in Southern Minnesota
The striped cucumber beetle, Acalymma vittatum (Fabricius) (Coleoptera: Chrysomelidae), is an important pest of cucurbit crops. However, the overwinter- ing capacity of this pest in temperate regions is poorly understood. In this study, the in-field survival of A. vittatum was examined during three consecutive winters. In addition, the supercooling points of A. vittatum were determined as an index of cold hardiness for adults. During each winter, the survival of adults decreased significantly through time, with no individuals surviving until spring. By comparing the supercooling points and in-field survival of adults to soil temperatures, it appears that winter temperatures in Minnesota are cold enough to induce freezing of the beetles. Moreover, a considerable amount of mortality occurred before minimum monthly soil temperatures dropped below the supercooling point of overwintering individuals, suggesting the occurrence of prefreeze mortality. An improved understanding of the response of A. vittatum to winter temperatures in temperate regions may aid in early season management of this pest
Full counting statistics of strongly non-Ohmic transport through single molecules
We study analytically the full counting statistics of charge transport
through single molecules, strongly coupled to a weakly damped vibrational mode.
The specifics of transport in this regime - a hierarchical sequence of
avalanches of transferred charges, interrupted by "quiet" periods - make the
counting statistics strongly non-Gaussian. We support our findings for the
counting statistics as well as for the frequency-dependent noise power by
numerical simulations, finding excellent agreement.Comment: 4+ pages, 2 figures; minor changes, version published in Phys. Rev.
Let
Insect pest and their control - Potato moth control
THE potato moth, Gnorimoschema operculella Zell., is almost world-wide in its distribution and can cause considerable damage to both potato crops and stored potatoes. The adult insect is a small inconspicuous, grey moth. The caterpillars cause the damage and they are, when fully grown, about half an inch long and pale greenish white in colour. They eat into the leaf and feed between the leaf surfaces and even work down the leaf stalks into the stems. Tubers may be damaged in the ground by caterpillars entering through cracks in the soil
A para-differential renormalization technique for nonlinear dispersive equations
For \alpha \in (1,2) we prove that the initial-value problem \partial_t
u+D^\alpha\partial_x u+\partial_x(u^2/2)=0 on \mathbb{R}_x\times\mathbb{R}_t;
u(0)=\phi, is globally well-posed in the space of real-valued L^2-functions. We
use a frequency dependent renormalization method to control the strong low-high
frequency interactions.Comment: 42 pages, no figure
Imaging Photon Lattice States by Scanning Defect Microscopy
Microwave photons inside lattices of coupled resonators and superconducting
qubits can exhibit surprising matter-like behavior. Realizing such open-system
quantum simulators presents an experimental challenge and requires new tools
and measurement techniques. Here, we introduce Scanning Defect Microscopy as
one such tool and illustrate its use in mapping the normal-mode structure of
microwave photons inside a 49-site Kagome lattice of coplanar waveguide
resonators. Scanning is accomplished by moving a probe equipped with a sapphire
tip across the lattice. This locally perturbs resonator frequencies and induces
shifts of the lattice resonance frequencies which we determine by measuring the
transmission spectrum. From the magnitude of mode shifts we can reconstruct
photon field amplitudes at each lattice site and thus create spatial images of
the photon-lattice normal modes
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