119,889 research outputs found
Assessment of site investigation and tunnel contract cost
The thesis concerns the research into the development and application of empirical guidelines regarding the capability of site investigation to define uncertainty in ground conditions and hence to minimise contract cost. The data has been abstracted from the documents of contracts on the Northumbrian Water Authority's Tyneside Sewerage Scheme and, to allow cost comparisons to be made, a system of index-linking costs has been used, which removes their time-dependency. A simplified theoretical approach, based on probability theory and decision analysis, has been included to model the situation of decision under uncertainty and comparisons are subsequently made between this approach and the empirical results. Conclusions are reached regarding the possible reduction in risk, financial uncertainty, with increasing site investigation
Computer program provides steady state analysis for liquid propellant propulsion systems
Computer program uses Bernoullis formula and Newton-Raphson method to provide steady state fluid flow analysis of line pressure drop in a system with six outlets for each of two main storage tanks. Program flexibility arises in the ease with which changes in the fluid line geometry can be made
Scribable coating for plastic films
Scribable opaque coating for transparent plastic film tape is not affected by aging, vacuum, and moderate temperature extremes. It consists of titanium dioxide, a water-compatible acrylic polymer emulsion, and a detergent. The coating mixture is readily dispersed in water before it is dried
Horn feed having overlapping apertures Patent
Characteristics of antenna horn feeds consisting of central horn with overlapping peripheral horn
Folly to the Greeks: Good Reasons to Give up Reason
A discussion of why a strong doctrine of 'reason' may not be worth sustaining in the face of modern scientific speculation, and the difficulties this poses for scientific rationality, together with comments on the social understanding of religion, and why we might wish to transcend common sense
Planetary astronomy
The goal is to use a variety of observational techniques and instruments to reduce, interpret, and synthesize groundbased astronomical data concerning the comets, asteroids, and other small bodies of the solar system in order to study the compositions, physical characteristics, population properties, and evolution of these bodies. This year's research has involved five distinct efforts. Chapman has studied asteroids, with emphasis on synthesizing groundbased databases to determine surface mineralogies and population characteristics; many new results on astronomy, size-distributions, and asteroid family traits have been obtained
Effects of inlet treatment location and treatment cavity depth on compressor noise
The ability of acoustic liners to reduce compressor noise inside and in front of an inlet was studied. An axial flow research compressor and a specially designed inlet were used inside an anechoic chamber. Acoustic and performance data were obtained for a range of inlet treatment locations and cavity depths to determine their effects on inlet noise over a range of blade passing frequencies. The greatest noise reductions in front of the inlet were obtained with acoustic treatment located close to the compressor and backed with the deepest cavities tested. Inside the inlet the maximum noise level reductions were obtained in the area of the treatment regardless of treatment location. No appreciable losses in compressor performance were measured
Quantum Hall-like effect on strips due to geometry
In this Letter we present an exact calculation of the effective potential
which appears on a helicoidal strip. This potential leads to the appearance of
lcalized states at a distance \xi_0 from the central axis. The twist \omega of
the strip plays the role of a magnetic field and is responsable for the
appearance of these localized states and an effective transverse electric field
thus this is reminiscent of the quantum Hall effect. At very low temperatures
the twisted configuration of the strip may be stalilized by the electronic
states.Comment: 3 page
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