188,148 research outputs found
Greenback-Gold Returns and Expectations of Resumption, 1862-1879
We propose a unified framework for studying the greenback-gold price during the U.S. suspension of convertibility from 1862 to 1879. The gold price is viewed as a floating exchange rate, with a fixed destination given by gold standard parity because of the prospect of resumption. We test this perspective using daily data for the entire period, and measure the effect of news during and after the Civil War. New evidence of a decline in the volatility of gold returns after the Resumption Act of 1875 provides statistical support for the importance of expectations of resumption.greenbacks, gold standard, regime switching
Formation of Topological Black holes from Gravitational Collapse
We consider the gravitational collapse of a dust cloud in an asymptotically
anti de Sitter spacetime in which points connected by a discrete subgroup of an
isometry subgroup of anti de Sitter spacetime are identified. We find that
black holes with event horizons of any topology can form from the collapse of
such a cloud. The quasilocal mass parameter of such black holes is proportional
to the initial density, which can be arbitrarily small.Comment: latex, 16 pages, four postscript figure
Interaction of electronic current with hypersonic waves in solids quarterly progress report no. 3, apr. 1 - jun. 31, 1964
Electronic current interaction with hypersonic waves in cadmium sulfide crysta
Star tracking reticles
A method for the production of reticles, particularly those for use in outer space, where the product is a quartz base coated with highly adherent layers of chromium, chromium-silver, and silver vacuum deposited through a mask, and then coated with an electrodeposit of copper from a copper sulfate solution followed by an electrodeposit of black chromium is described. The masks are produced by coating a beryllium-copper alloy substrate with a positive working photoresist, developing the photoresist, according to a pattern to leave a positive mask, plating uncoated areas with gold, removing the photoresist, coating the substrate with a negative working photoresist, developing the negative working photoresist to expose the base metal of the pattern, and chemically etching the unplated side of the pattern to produce the mask
Process for the production of star-tracking reticles
Reticles designed with quartz bases are masked with desired pattern and then are coated with highly adherent layers of chromium, chromium silver alloy, silver, copper, and black chromium (mixture of chromium and chromium oxides). Black chromium final layer produces required nonreflective surface
Clearing Alaskan water supply impoundments: management, laboratory study, and literature review
The literature review prepared in conjunction with this study is contained in IWR-67-A, published separately as "Clearing Alaskan Water Supply Impoundments: Literature Review" by the Institute of Water Resources, University of Alaska, Fairbanks, Alaska. The data developed in the laboratory portion of the study are contained in IWR-67-B. Contact the Institute of Water Resources for access to this material. IWR-67-A and IWR-67-B are available on microfiche.Water supply impoundments in northern regions have seen only limited application. Reasons for the lack of use of such impoundments include the following: 1) little demand for water due to the low population densities and rustic life styles; 2) a lack of conventional distribution systems in many communities; 3) poorly developed technology for construction of dams on permafrost; 4) adequacy of existing river, lake, ice, and lagoon water supplies; 5) shortage of capital to finance the high cost of construction in remote regions.The work upon which this report is based was supported by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized by the Water Resources Research Act of 1964, Public Law 88-379, as amended (Project A-043-ALAS)
Formation of star tracking reticles
The present application is directed towards a process for producing high resolution, substantially non-reflective reticles or choppers suitable for use for transmitting in both the visible and near ultra-violet regions, able to withstand reasonable handling and extreme environmental conditions, and capable of operating at speeds of from 2800 to about 9000 revolutions per minute without distortion. In particular, the present invention is directed towards the production or reticles having a quartz base vacuum coated with chromium, chromium-silver alloy, and silver with electrodeposited copper and black chromium thereon, respectively, in the form of a reticle pattern. The quartz permits the transmission of light while the pattern is opaque to light. The reticles of the present invention are intended for use in optical trackers, such as star trackers used in outer space
Wishart variate generators
Subroutine WSHRT for generating matrix of variances and covariances of Wishart distributio
Rotorcraft-based emergency medical services in the Caribbean Basin
There is a pressing need for improved health care in general and emergency health care in particular throughout the Caribbean Basin. The importance of rotorcraft as an integral part of the needed system of emergency medical care in the region was investigated. Many of the larger countries in the region currently have the needed infrastructure to implement a national system of rotorcraft-based emergency medical centers within their borders. By helping to establish a system of rotorcraft based health care centers in strategic locations in the Lesser Antilles, the U.S. can assist the islands of the region by demonstrating the concept and establishing a potential training site for the other larger countries of the region. There is sufficient demand for rotorcraft based emergency health care within the Lesser Antilles to locate one center on the island of Puerto Rico and another one of the southern-most islands. With the use of fixed wing aircraft or long range helicopters, the two rotorcraft based centers could provide the region with rapid and efficient emergency health care. The superior speed and range of the XV-15 Tilt Rotor aircraft make it an attractive possibility for emergency transport and rescue in this region
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