42,988 research outputs found
Properties of the conjugate gradient and Davidon methods, part 5 Final report
Quadratically convergent gradient methods for minimizing unconstrained function of several variable
Grosse Ile and the Irish Memorial National Historic Site, Parks Canada: A Case Study
Focuses on values and their protection by examining the place of values in management. Grosse Ile's management is still evolving, and the eventful first phases of planning are still fresh in the minds of staff
Coefficients and terms of the liquid drop model and mass formula
The coefficients of different combinations of terms of the liquid drop model
have been determined by a least square fitting procedure to the experimental
atomic masses. The nuclear masses can also be reproduced using a Coulomb radius
taking into account the increase of the ratio with increasing
mass, the fitted surface energy coefficient remaining around 18 MeV
The one-dimensional Stefan problem with non-Fourier heat conduction
We investigate the one-dimensional growth of a solid into a liquid bath,
starting from a small crystal, using the Guyer-Krumhansl and Maxwell-Cattaneo
models of heat conduction. By breaking the solidification process into the
relevant time regimes we are able to reduce the problem to a system of two
coupled ordinary differential equations describing the evolution of the
solid-liquid interface and the heat flux. The reduced formulation is in good
agreement with numerical simulations. In the case of silicon, differences
between classical and non-classical solidification kinetics are relatively
small, but larger deviations can be observed in the evolution in time of the
heat flux through the growing solid. From this study we conclude that the heat
flux provides more information about the presence of non-classical modes of
heat transport during phase-change processes.Comment: 29 pages, 6 figures, 2 tables + Supplementary Materia
Dilution jet mixing program, phase 3
The objectives of the program were: (1) to extend the data base on mixing of a single-sided row of jets with a confined crossflow, (2) to collect a data base on mixing of multiple rows of jets with confined crossflow, (3) to develop empirical jet mixing correlations, and (4) to perform limited three-dimensional calculations for some of these test configurations. The tests were performed with uniform mainstream conditions for several orifice plate configurations. Schematics of the test section and the orifice configurations are given. Temperature and pressure measurements were made in the test section at 4 axial and 11 transverse stations, using a 60-element rake probe. The measured temperature distributions for these tests are reported
Towards an Improved Test of the Standard Model's Most Precise Prediction
The electron and positron magnetic moments are the most precise prediction of
the standard model of particle physics. The most accurate measurement of a
property of an elementary particle has been made to test this result. A new
experimental method is now being employed in an attempt to improve the
measurement accuracy by an order of magnitude. Positrons from a "student
source" now suffice for the experiment. Progress toward a new measurement is
summarized
Monitoring the dispersion of ocean waste disposal plumes from ERTS-1 and Skylab
The author has identified the following significant results. About forty miles off the Delaware coast is located the disposal site for waste discharged from a plant processing titanium dioxide. The discharge is a greenish-brown; 15-20% acid liquid which consists primarily of iron chlorides and sulfates. The barge which transports this waste has a 1,000,000 gallon capacity and makes approximately three trips to the disposal site per week. ERTS-1 MSS digital tapes are being used to study the dispersion patterns and drift velocities of the iron-acid plume. Careful examination of ERTS-1 imagery disclosed a fishhook-shaped plume about 40 miles east of Cape Henlopen caused by a barge disposing acid wastes. The plume shows up more strongly in the green band than in the red band. Since some acids have a strong green component during dumping and turn slowly more brownish-reddish with age, the ratio of radiance signatures between the green and red bands may give an indication of how long before the satellite overpass the acid was dumped. Enlarged enhancements of the acid waste plumes, prepared from the ERTS-1 MSS digital tapes aided considerably in studies of the dispersion of the waste plume. Currently acid dumps are being coordinated with ERTS-1 overpasses
Inventory of wetland habitat using remote sensing for the proposed Oahe irrigation unit in eastern South Dakota
An inventory of wetlands for the area included in the proposed Oahe irrigation project was conducted to provide supplemental data for the wildlife mitigation plan. Interpretation techniques for inventoring small wetlands in the low relief terrain of the Lake Dakota Plain were documented and data summaries included. The data were stored and tabulated in a computerized spatial data analysis system
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