A general method for morphologic dating of hillslopes

Geology ◽  
2005 ◽  
Vol 33 (8) ◽  
pp. 693-695
Author(s):  
David B. Nash
Keyword(s):  
Diffusion Equation ◽  
Slope Angle ◽  
Specific Model ◽  
Equation Model ◽  
Independent Function ◽  
Hillslope Evolution ◽  
Dating Methods ◽  
Dating Method ◽  
General Method

Abstract Morphologic dating of hillslopes is the determination of the age of a hillslope by its morphology. Current methods match the observed morphology with the morphology predicted by the diffusion-equation model for hillslope evolution. The morphologic dating method presented here requires no specific model for evolution, but is only applicable to transport-limited hillslopes on which the downslope debris flux is some scale- and time-independent function of slope angle. If these conditions are met, changes in morphology with scale (e.g., height) for a set of hillslopes of a fixed age are identical to changes in morphology with time for a hillslope of a fixed scale. This fact provides the basis for a simple, generally applicable method for morphologically dating such hillslopes with any initial morphology. This new dating method may be applied to a wide variety of vegetated hillslopes in temperate humid regions and is an improvement over previous morphologic dating methods that relied on the diffusion-equation model.

MANUFACTURE INVESTIGATION OF CARTRIDGE WITH BOTTOM-MOST PART FLANGE BY DIRECT EXTRUSION WITH COUNTERPUNCH. REPORT 13. DETERMINATION OF DEFORMED STATE UNDER STRAITENED EXTRUSION IN FOURTH CENTRAL AREA OF PLASTIC DEFORMATION

2020 ◽  
Vol 0 (4) ◽  
pp. 43-51
Author(s):  
A. L. Vorontsov ◽  
◽  
I. A. Nikiforov ◽  
Keyword(s):  
Plastic Deformation ◽  
Plastic Flow ◽  
Central Area ◽  
Direct Extrusion ◽  
Deformed State ◽  
Cumulative Deformation ◽  
The Given ◽  
General Method

Formulae have been obtained that are necessary to calculate cumulative deformation in the process of straitened extrusion in the central area closed to the working end of the counterpunch. The general method of plastic flow proposed by A. L. Vorontsov was used. The obtained formulae allow one to determine the deformed state of a billet in any point of the given area. The formulae should be used to take into account the strengthening of the extruded material.

The determination of sedimentation rates in Lake Ontario using the 210Pb dating method

1978 ◽  
Vol 15 (3) ◽  
pp. 431-437 ◽  
Author(s):  
John G. Farmer
Keyword(s):  
Sedimentation Rate ◽  
Lake Ontario ◽  
Sedimentary Basins ◽  
210Pb Dating ◽  
Sedimentation Rates ◽  
Surface Mixing ◽  
Dating Method ◽  
210Pb Dating Method

The 210Pb dating method has been applied successfully to the determination of recent sedimentation rates at four sites distributed among the three major sedimentary basins (Niagara, Mississauga and Rochester) of Lake Ontario. Following correction for effects due to compaction of the sediments, mean sedimentation rates ranging from 0.02 cm/year at the periphery of the Mississauga basin to 0.11 cm/year in the Niagara and Rochester basins were determined. Allowance for compaction reduced the non-compaction-corrected sedimentation rates by 20–35%. Neither 210Pb nor fallout 137Cs profiles indicated surface mixing of sediment sufficient to noticeably affect the calculated sedimentation rates. At all four sites, the sedimentation rate seems to have remained constant during the last 100–150 years.

Determination of the Instantaneous Pole Axes in Single-DOF Spherical Mechanisms

2008 ◽  
Author(s):  
Raffaele Di Gregorio
Keyword(s):  
A Algorithm ◽  
Planar Mechanisms ◽  
Spherical Mechanisms ◽  
Kinematic Behavior ◽  
General Method

In spherical mechanisms, the instantaneous pole axes play the same role as the instant centers in planar mechanisms. Notwithstanding this, they are not fully exploited to study the kinematic behavior of spherical mechanisms as the instant centers are for planar mechanisms. The first step to make their use possible and friendly is the availability of efficient techniques to determine them. This paper presents a general method to determine the instantaneous pole axes in single-dof spherical mechanisms as a function of the mechanism configuration. The presented method is directly deduced from a algorithm already proposed by the author for the determination of the instant centers in single-dof planar mechanisms.

scholarly journals Numerical Solution of Fractional Diffusion Equation Model for Freezing in Finite Media

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
R. S. Damor ◽  
Sushil Kumar ◽  
A. K. Shukla
Keyword(s):  
Diffusion Equation ◽  
Interface Velocity ◽  
Biological Tissues ◽  
Fractional Diffusion ◽  
Equation Model ◽  
Fractional Diffusion Equation ◽  
Heat Transfer Analysis ◽  
Engineering Sciences ◽  
Space Fractional Diffusion Equation ◽  
Fractional Differential

Phase change problems play very important role in engineering sciences including casting of nuclear waste materials, vivo freezing of biological tissues, solar collectors and so forth. In present paper, we propose fractional diffusion equation model for alloy solidification. A transient heat transfer analysis is carried out to study the anomalous diffusion. Finite difference method is used to solve the fractional differential equation model. The temperature profiles, the motion of interface, and interface velocity have been evaluated for space fractional diffusion equation.

scholarly journals The physical basis of the fission wave reactor

2008 ◽  
Vol 23 (2) ◽  
pp. 3-15 ◽  
Author(s):  
Volodymyr Pavlovych ◽  
Volodymyr Khotyayintsev ◽  
Olena Khotyayintseva
Keyword(s):  
Diffusion Equation ◽  
Main Idea ◽  
Stationary Wave ◽  
Short Review ◽  
Nuclear Fission ◽  
Stationary Processes ◽  
Wave Parameters ◽  
Nuclear Burning ◽  
Fission Wave

The main idea of slow nuclear fission wave reactor is discussed and short review of the existing works is also presented. The aim of this paper is to clarify the physics of processes, which define the stationary wave of nuclear burning, and to develop the approaches determining the wave parameters. It is shown that the diffusion equation for fluence can be used to describe the stationary and non-stationary processes in the nuclear fission wave. Two conditions of stationary wave existence are first formulated in the paper. The rule of determination of wave velocity as the eigenvalue of boundary problem is also formulated.

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