2,755 research outputs found
Fuse-holder concept expedites electronic component changes
Mounting circuit components in fuse holders facilitates component changing and extends component life with an estimated fifty percent saving of breadboard test time. Glass sleeves of the fuse holders allow easy component identification
Coded photographic proof paper could serve as convenient densitometer
Standard print-out proofing paper, preprinted with an identifying code, serves as convenient densitometer. Exposure to light darkens the paper and gives a measure of the density of the resultant photographic image or the total amount of exposure sustained by the paper
Study of adhesion and cohesion in vacuum Final report
Vacuum metal-metal bonding tests to determine conditions of accidental adhesion of spacecraft structural material
Study of adhesion and cohesion in vacuum summary report 1 jul. 1963 - 30 jun. 1964
Adhesion and cohesion of metal couples in vacuum chambe
Preliminary Engineering Geology Report of Dam Sites on the East Fork of the Muscatatuck River in Scott, Jennings, and Jefferson Counties, Indiana
Preliminary engineering geology investigations have been made
of four proposed dam sites and their reservoir areas in the valley
of the East Fork of the Muscatatuck River and its tributaries, Big
Camp and Big Graham Creeks, in northern Scott County, southern
Jennings County, and western Jefferson County, Ind. In this report
the geologic column of the area has been divided, according to engineering
characteristics, into five units. The bedrock consists
of (in ascending order) unit 1, the Osgood Formation and the Laurel
Limestone of Silurian age; unit 2, the Waldron Shale and the Louisville
Limestone of Silurian age and the Geneva Dolomite and the
Jeffersonville Limestone of Devonian age; unit 3~ the North Vernon
Limestone of Devonian age; and unit 4~ the Devonian portion of the
New Albany Shale. These rocks are overlain at most places by
unit 5, the unconsolidated materials that range in character from
red residual limestone soils to glacial till.
The bedrock formations stratigraphically below the North
Vernon Limestone (units 1 and 2) are essentially sound rock and
offer few problems to dam and reservoir construction except the
possibility of a small amount of leakage. The Jeffersonville Limestone
(the top formation of unit 2) includes a gray limestone bed
that contains a few solution channels, but otherwise it is sound rock.
Most of the solution channels and sinkholes in the area have been
formed in the North Vernon Limestone (unit 3), and serious leakage
from the reservoir probably would occur through this formation if
it were not extensively grouted. The New Albany Shale (unit 4)
weathers quickly where it is exposed at the surface, and spillways
on the New Albany Shale must be designed to prevent the rapid erosion
of the shale under the attack of running water. The red residual
limestone soils (of unit 5) have high liquid limits, but these
materials would make a satisfactory impermeable clay core of an
earth dam. The other unconsolidated materials (glacial till, outwash
silt and sand, and loess) overlying the bedrock are thin but
sufficient in quantity to provide fill material for earth dams. Quarries
could be opened in the limestone formations at any of the dam
sites to supply concrete aggregate and fill material
Linked disturbance interactions in South-Central Alaska: implications for ecosystems and people
Thesis (M.S.) University of Alaska Fairbanks, 2013Communities and ecosystems in the Alaskan boreal forest are undergoing substantial change. People contribute to this change. They are also impacted by the consequences. For example, wildfire and spruce bark beetle (Dendroctonus rufipennis) outbreaks have increased in frequency and severity due to warming trends, affecting the ecosystem and services important to people. I conducted a study to explore the social and ecological implications of changing natural disturbances. I evaluated how the occurrence of spruce bark beetle outbreak has altered the probability of wildfire between 2001 and 2009 on the Kenai Peninsula, Alaska. Modeling the effects of bark beetle outbreak on the probability of large wildfire (> 500 ha) and small wildfires ( 3.3 ha and the bark-beetle outbreak increased property values. Wildfires <3.3 ha decreased property values.Chapter 1. General introduction -- Chapter 2. Linked disturbance interactions in South-Central Alaska: the effects of a spruce bark beetle (Dendroctonus rufipennis) outbreak on a changing boreal wildfire regime -- Chapter 3. The effects of a spruce bark beetle outbreak and wildfires on property values in the wildland-urban interface of South-central, Alaska, USA -- 4. General conclusions
Verification in Staged Tile Self-Assembly
We prove the unique assembly and unique shape verification problems,
benchmark measures of self-assembly model power, are
-hard and contained in (and in
for staged systems with stages). En route,
we prove that unique shape verification problem in the 2HAM is
-complete.Comment: An abstract version will appear in the proceedings of UCNC 201
Surface Flaw Detection with Ferromagnetic Resonance Probes
Ferromagnetic probes resonating at microwave frequencies have previously been shown to function as sensitive detectors of surface breaking flaws in metals. A swept frequency mode of operation was used, with the resonance line of the probe displayed on an oscilloscope and the presence of a flaw indicated by a shift of the resonance line. This type of presentation lacks good discrimination between lift-off and and flaw signals and also reduces the probe scanning speed because the entire resonance line must be swept at each measurement point on the test specimen. Our new system operates under cw conditions, with a network analyser type of display giving the probe input impedance in polar coordinates. This provides liftoff discrimination and also enhances sensitivity. Experimental curves and their theoretical interpretations will be presented, and a portable prototype instrument will be described
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