Package org.jreliability.function.common

Class HjorthReliabilityFunction

java.lang.Object

org.jreliability.function.SequentialFunction

org.jreliability.function.common.HjorthReliabilityFunction

All Implemented Interfaces:

Function, ReliabilityFunction

public class HjorthReliabilityFunction
extends SequentialFunction
implements ReliabilityFunction

The HjorthReliabilityFunction represents the Hjorth ReliabilityFunction

R(x) = 1 - F(x) = (e^-((delta * x^2)/2)) / ((1 + beta * x)^(theta / beta))
with beta, delta, theta > 0.

While the parameter beta scales the reliabilityFunction, the parameters delta and theta determine the shape of the reliabilityFunction. This function is especially interesting since bathtub-shaped failure rates can be modeled.

Field Summary

Fields

Modifier and Type	Field	Description
protected final double	beta	The beta parameter scales the HjorthReliabilityFunction.
protected final double	delta	The delta parameter shapes the HjorthReliabilityFunction.
protected final double	theta	The theta parameter shapes the HjorthReliabilityFunction.

Constructor Summary

Constructors

Constructor	Description
HjorthReliabilityFunction(double beta, double delta, double theta)	Constructs a HjorthReliabilityFunction with a given beta, delta, and theta.

Method Summary

Modifier and Type	Method	Description
double	getY(double x)	Returns the y value for y = f(x).

Methods inherited from class org.jreliability.function.SequentialFunction

getY

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.jreliability.function.Function

getY

Field Details

beta

protected final double beta

The beta parameter scales the HjorthReliabilityFunction.

delta

protected final double delta

The delta parameter shapes the HjorthReliabilityFunction.

theta

protected final double theta

The theta parameter shapes the HjorthReliabilityFunction.

Constructor Details

HjorthReliabilityFunction

public HjorthReliabilityFunction(double beta,
 double delta,
 double theta)

Constructs a HjorthReliabilityFunction with a given beta, delta, and theta.

Parameters:

beta - the scale value

delta - the first shape value

theta - the second shape value

Method Details

getY

public double getY(double x)

Description copied from interface: Function

Returns the y value for y = f(x).

Specified by:

getY in interface Function

Parameters:

x - the x value

Returns:

the y for y = f(x)