ITEM CHARACTERISTIC CURVE SOLUTIONS TO THREE INTRACTABLE TESTING PROBLEMS1

Water Retention and Characteristic Curve

A soil-water characteristic (SWC) curve describes the amount of water retained in a soil (expressed as mass or volume water content, m or v) under equilibrium at a given matric potential. An SWC is an important hydraulic property, related to size and connectedness of pore spaces, hence strongly affected by soil texture and structure, and by other constituents, including organic matter. Modeling...

Characteristic Points of Stress-Strain Curve at High Temperature

Determination of critical points on hot stress-strain curve of metals is crucial in thermo-mechanical processes design. In this investigation a mathematical modeling is given to illustrate the behavior of metal during hot deformation processes such as hot rolling. The critical strain for the onset of dynamic recrystallization has been obtained as a function of strain at the maximum stress. In a...

A Concise Introduction to Receiver Operating Characteristic (ROC) Curve

ROC curve analysis is used widely in medicine as a method for evaluating the performance of diagnostic tests (3,5,6,10), but has been used recently in many agricultural applications (2,4,5,11,12). The ROC curve provides information regarding how often a test’s predictions are correct, and provides a graphical method for evaluating and discriminating between different diagnostic tests or modific...

Lifting an automorphism of a curve to characteristic zero

Question. Given a connected curve C 0 , proper and smooth over a field K of characteristic p, given a subgroup H ⊂ Aut(C 0); can we lift the pair (C 0 , H) to characteristic zero? ((We shall see that the answer is " NO " in general; for cyclic groups we conjecture that the answer is " YES " .)) Example (1) (Roquette). Consider the normalization of the completion of the curve given by the affine...

An intuitive approach to receiver operating characteristic curve analysis.