Conference Papers
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Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Associations of free-living bacteria and dissolved organic compounds in a plume of contaminated groundwater
Associations of free-living bacteria (FLB) and dissolved organic contaminants in a 4-km-long plume of sewage-contaminated groundwater were investigated. Abundance of FLB in the core of the plume (as delineated by maximum specific conductance) steadily decreased in the direction of flow from a point 0.25 km downgradient from the source to the toe of the plume. At 0.25 km downgradient, FLB comprised
Authors
R.W. Harvey, L.B. Barber
Atmospheric circulation and precipitation in the Sierra Nevada
No abstract available
Authors
D.R. Cayan, L. Riddle
Causes of mortality in common loons
Summarized are necropsy results from 222 carcasses of Common Loons (Gavia immer) submitted to the National Wildlife Health Research Center from 1976 through 1991. The carcasses were from 18 states, and 10 or more birds each were from Minnesota, Florida, Virginia, Michigan, Wisconsin, Maine, and North Carolina. Seventy-three (33%) carcasses were emaciated, and in some of these birds emaciation wa
Authors
J. Christian Franson, David J. Cliplef
Changes in abundance of migratory land birds in conifer forests of western North America
No abstract available at this time
Authors
G. Cox, B.E. Kus
Classifying and mapping wetlands and peat resources using digital cartography
Digital cartography allows the portrayal of spatial associations among diverse data types and is ideally suited for land use and resource analysis. We have developed methodology that uses digital cartography for the classification of wetlands and their associated peat resources and applied it to a 1:24 000 scale map area in New Hampshire. Classifying and mapping wetlands involves integrating the s
Authors
Cornelia C. Cameron, David A. Emery
Climatic changes near the Great Lakes inferred from 141 year ice records
Freeze-up and break-up dates and duration of ice cover for lakes and rivers represent an integration of weather conditions prior to the specified event(s). Changes in mean ice conditions may be used as quantitative indicators of climatic changes if long homogenous ice records are accompanied by sufficiently homogenous air temperature records to calibrate the changes in mean ice cover in terms of c
Authors
Raymond A. Assel, Dale M. Robertson
Comparison of three newton-like nonlinear least-squares methods for estimating parameters of ground-water flow models
Three methods of solving nonlinear least-squares problems were compared for robustness and efficiency using a series of hypothetical and field problems. A modified Gauss-Newton/full Newton hybrid method (MGN/FN) and an analogous method for which part of the Hessian matrix was replaced by a quasi-Newton approximation (MGN/QN) solved some of the problems with appreciably fewer iterations than requir
Authors
R.L. Cooley, M. C. Hill
Computer simulation of dry layered granular flow down an incline composed of grains
Experiments show that gravity-driven dry granular flows are essentially layered for smooth spheres. This paper describes layer-to-layer interaction in the flow. Assuming two-dimensional flow and neglecting the interaction of grains within the same layer, one may idealize the problem as an elastic sphere under external forces moving down an incline within a layer of identical spheres placed equally
Authors
Chi-Hai Ling, Chyan-Deng Jan
D4Z: A new renumbering for iterative solution of ground-water flow and solute-transport equations
D4 zig-zag (D4Z) is a new renumbering scheme for producing a reduced matrix to be solved by an incomplete LU preconditioned, restarted conjugate-gradient iterative solver. By renumbering alternate diagonals in a zig-zag fashion, a very low sensitivity of convergence rate to renumbering direction is obtained. For two demonstration problems involving groundwater flow and solute transport, iteration
Authors
K.L. Kipp, T.F. Russell, J.S. Otto
Data set for verification of 3-D free-surface hydrodynamic models, Carquinez Strait, California
No abstract available.
Authors
P. E. Smith, R.N. Oltmann, M.R. Simpson
Design and performance of a horizontal, axial-flow, water circulator
No abstract available at this time
Authors
R.D. Howerton, C.E. Boyd, B.J. Watten
Desk-top model buildings for dynamic earthquake response demonstrations
Models of buildings that illustrate dynamic resonance behavior when excited by hand are designed and built. Two types of buildings are considered, one with columns stronger than floors, the other with columns weaker than floors. Combinations and variations of these two types are possible. Floor masses and column stiffnesses are chosen in order that the frequency of the second mode is approximately
Authors
A. Gerald Brady