4,470 research outputs found
Native and Introduced Forage Plants
The true grasses are one of the most valuable families of plants. To them belong the small grains (oats, wheat, barley, etc.,), corn, the various sorts of cane, the great bamboo of Asia, and a host of other plants of more or Jess importance to man or beast. In the great prairie regions of the United States the grasses form by far the greater part of the natural vegetation and constitute one of the most valuable of the natural resources as well. In our own state of South Dakota stock-raising- has been one of the leading industries ever since its settlement, and will continue to be so for years to come. The state, as a whole, is peculiarly well adapted to stock-raising and dairying. One of the most important elements in this fitness is the great richness of the grass flora and of the native species in particular. About one hundred and sixty species of grasses are known to grow within the limits of the state. Of these, about one hundred and five are native to the soil, the remainder being found either under cultivation or introduced some other way. Some of them are weeds, but the majority are more or less useful as forage plants
Birds and beaches, dogs and leashes : dog owners\u27 sense of obligation to leash dogs on beaches in Victoria, Australia
Domesticated dogs threaten the conservation of beach-nesting birds in Australia through disturbance, and destruction of eggs and chicks. Leashing of dogs can improve conservation outcomes, but few dogs are leashed on beaches. We surveyed dog owners to explore their sense of obligation to leash dogs on beaches. Dog owners were more likely to feel obliged to leash their dog when they believed other people expected dogs to be leashed, and when they believed their dog was a threat to wildlife or people. Dog owners were less likely to feel obliged to leash their dog if they considered unleashed dog recreation to be important. Improved compliance may be achieved through community-based approaches to foster social norms for dog control, tailoring information products to emphasize the risk that all unleashed dogs may pose to beach-nesting birds and raising awareness of designated off-leash exercise dog recreation areas. <br /
The effects of turbulence intensity on the downstream performance of horizontal axis tidal stream turbines
This study focuses on a comparison of model results from a blade element momen-
tum computational fluid dynamics (BEM-CFD) steady state RANS model, and a BEMT model that accounts
for the wake generated from upstream turbines using analytic expressions. Rotor forces are
calculated using 3D hydrofoil profile data. Both techniques are validated against ex- isting
experimental data, and then used to assess the power extraction of downstream turbines. Turbulent
inflow conditions of 3% and 7% are applied, and the results of power extraction as- sessed.
Particular attention is paid to the velocity field, with respect to the downstream wake, to assess
how the turbulence characteristics effect the recovery rate and downstream power
potential. Both models highlight the different recovery rates of the two turbulent conditions
The response to high magnetic fields of the vacuum phototriodes for the compact muon solenoid endcap electromagnetic calorimeter
The endcap electromagnetic calorimeter of the Compact Muon Solenoid (CMS) detects particles with the dense fast scintillator lead tungstate (PbWO4). Due to the low light yield of this scintillator photodetectors with internal gain are required. Silicon avalanche photodiodes cannot be used in the endcap region due to the intense neutron flux. Following an extensive R&D programme 26 mm diameter single-stage photomultipliers (vacuum phototriodes) have been chosen as the photodetector in the endcap region. The first 1400 production devices are currently being evaluated following recent tests of a pre-production batch of 500 tubes. Tubes passing our acceptance tests have responses, averaged over the angular acceptance of the endcap calorimeter, corresponding to the range 20 to 55 electrons per MeV deposited in PbWO4. These phototriodes operate, with a typical gain of 10, in magnetic fields up to 4T.PPARC, EC(INTAS-CERN scheme 99-424
Cartan subalgebras in C*-algebras of Hausdorff etale groupoids
The reduced -algebra of the interior of the isotropy in any Hausdorff
\'etale groupoid embeds as a -subalgebra of the reduced
-algebra of . We prove that the set of pure states of with unique
extension is dense, and deduce that any representation of the reduced
-algebra of that is injective on is faithful. We prove that there
is a conditional expectation from the reduced -algebra of onto if
and only if the interior of the isotropy in is closed. Using this, we prove
that when the interior of the isotropy is abelian and closed, is a Cartan
subalgebra. We prove that for a large class of groupoids with abelian
isotropy---including all Deaconu--Renault groupoids associated to discrete
abelian groups--- is a maximal abelian subalgebra. In the specific case of
-graph groupoids, we deduce that is always maximal abelian, but show by
example that it is not always Cartan.Comment: 14 pages. v2: Theorem 3.1 in v1 incorrect (thanks to A. Kumjain for
pointing out the error); v2 shows there is a conditional expectation onto
iff the interior of the isotropy is closed. v3: Material (including some
theorem statements) rearranged and shortened. Lemma~3.5 of v2 removed. This
version published in Integral Equations and Operator Theor
Immediate reward reinforcement learning for clustering and topology preserving mappings
We extend a reinforcement learning algorithm which has previously been shown to cluster data. Our extension involves creating an underlying latent space with some pre-defined structure which enables us to create a topology preserving mapping. We investigate different forms of the reward function, all of which are created with the intent of merging local and global information, thus avoiding one of the major difficulties with e.g. K-means which is its convergence to local optima depending on the initial values of its parameters. We also show that the method is quite general and can be used with the recently developed method of stochastic weight reinforcement learning [14]
Graph Treewidth and Geometric Thickness Parameters
Consider a drawing of a graph in the plane such that crossing edges are
coloured differently. The minimum number of colours, taken over all drawings of
, is the classical graph parameter "thickness". By restricting the edges to
be straight, we obtain the "geometric thickness". By further restricting the
vertices to be in convex position, we obtain the "book thickness". This paper
studies the relationship between these parameters and treewidth.
Our first main result states that for graphs of treewidth , the maximum
thickness and the maximum geometric thickness both equal .
This says that the lower bound for thickness can be matched by an upper bound,
even in the more restrictive geometric setting. Our second main result states
that for graphs of treewidth , the maximum book thickness equals if and equals if . This refutes a conjecture of Ganley and
Heath [Discrete Appl. Math. 109(3):215-221, 2001]. Analogous results are proved
for outerthickness, arboricity, and star-arboricity.Comment: A preliminary version of this paper appeared in the "Proceedings of
the 13th International Symposium on Graph Drawing" (GD '05), Lecture Notes in
Computer Science 3843:129-140, Springer, 2006. The full version was published
in Discrete & Computational Geometry 37(4):641-670, 2007. That version
contained a false conjecture, which is corrected on page 26 of this versio
Characterization of skeletal phenotypes of TRα1(PV) and TRβ(PV) mutant mice: implications for tissue thyroid status and T3 target gene expression
Bone development is extremely sensitive to alterations in thyroid status. Recently, we analyzed the skeletal phenotypes of mice with the dominant negative resistance to thyroid hormone (RTH) mutation PV targeted to either the thyroid hormone receptor (TR) α1 or β gene. This perspective summarizes our findings to date and explores the wider implications for thyroid status and T3 target gene expression in individual tissues
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Radioactive-materials shipping-cask anticontamination enclosure
An anticontamination device for use in storing shipping casks for radioactive materials comprises (1) a seal plate assembly; (2) a double-layer plastic bag; and (3) a water management system or means for water management
Measurement of Fluorescence Phenomena from Yttrium and Gadolinium Oxysulfide Phosphors using a 45-MeV Proton Beam
This research was sponsored by the National Science Foundation Grant NSF PHY-931478
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