4.- OBTENCION DE LAS FUERTES RADIACTIVAS UTILIZADAS EN ESTE TRABAJO

The Edge Detection Group Sub−Library contains the blocks described in Subsections 6.3.1 through 6.3.7 below.

6.3.1 The Detect Increase Block

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The Detect Increase block determines if an input is strictly greater than its previous value. The output is true (not 0), when the input signal is greater than its previous value. The output is false (equal to 0), when the input signal is less than or equal to its previous value.

Example 6.12

We will create a model with the Detect Increase block to display changes in output for changes in the input.

The model is shown in Figure 6.15 and the input and output waveforms are shown in Figure 6.16.

In Figure 6.15, the Signal Generator block is specified for a square waveform of amplitude 1 and frequency 0.5, the Unit Delay is included to delay the Step block one time unit, the Detect Increase block initial value is specified as 0, and the Convert Block is used to convert the output signal of the Detect Change block from uint(8) to double. The waveforms in Figure 6.16 indicate that the output is true (not 0), when the input signal is greater than its previous value. The output is false (equal to 0), when the input signal is less than or equal to its previous value.

Figure 6.15. Model for Example 6.12

Figure 6.16. Input and output waveforms for the model of Figure 6.15

6.3.2 The Detect Decrease Block

The Detect Decrease block determines if an input is strictly less than its previous value where the output is true (not 0), when the input signal is less than its previous value, and the output is false (equal to 0), when the input signal is greater than or equal to its previous value.

Example 6.13

We will create a model with the Detect Decrease block to display changes in output for changes in the input.

The model is shown in Figure 6.17 and the input and output waveforms are shown in Figure 6.18.

In Figure 6.17, the Signal Generator block is set for a square waveform of amplitude 1 and fre-quency 0.5, the Unit Delay is included to delay the Step block one time unit, the Detect Decrease block initial value was set to 0, and the Convert Block is used to convert the output signal of the Detect Change block from uint(8) to double. The waveforms in Figure 6.18 indicate that the out-put waveform is true (not 0), when the inout-put signal is less than its previous value, and the outout-put is false (equal to 0), when the input signal is greater than or equal to its previous value.

Figure 6.17. Model for Example 6.13

Figure 6.18. Input and output waveforms for the model of Figure 6.17

6.3.3 The Detect Change Block

The Detect Change block determines if an input does not equal its previous value where the out-put is true (not 0), when the inout-put signal does not equal its previous value, and the outout-put is false (equal to 0), when the input signal equals its previous value.

Example 6.14

We will create a model with the Detect Change block to display changes in output for changes in the input.

The model is shown in Figure 6.19 and the input and output waveforms are shown in Figure 6.20.

In Figure 6.19, the Detect Change block value was set to 0, and the Convert Block is used to con-vert the output signal of the Detect Change block from uint(8) to double. The waveforms in Fig-ure 6.20 indicate that the output waveform is 0 for the interval because the step function is also 0 during this interval. At the step function jumps to 1 and thus the output assumes a non−zero value, in this case 1. For , there are no further changes in the input signal and thus the output drops to 0 indicating that the input signal equals its previous value.

Figure 6.19. Model for Example 6.14

Figure 6.20. Input and output waveforms for the model of Figure 6.19 0 t 1< <

t = 1 t 1>

6.3.4 The Detect Rise Positive Block

The Detect Rise Positive block determines if the input is strictly positive, and its previous value was nonpositive. The output is true (not 0), when the input signal is greater than zero, and its pre-vious value was less than zero. The output is false (equal to 0), when the input is negative or zero, or if the input is positive and its previous value was also positive.

Example 6.15

We will create a model with the Detect Rise Nonnegative block to display changes in output for changes in the input.

The model is shown in Figure 6.21 and the input and output waveforms are shown in Figure 6.22.

Figure 6.21. Model for Example 6.15

Figure 6.22. Input and output waveforms for the model of Figure 6.21

In Figure 6.21, the Signal Generator block is specified as a square waveform of amplitude 1 and frequency 0.5, the Unit Delay is included to delay the Step block one time unit, the Detect Rise

Nonnegative block initial value was set to 0, and the Convert Block is used to convert the output signal of the Detect Change block from uint(8) to double. The waveforms in Figure 6.22 indicate that the output is true (not 0), when the input signal is greater than zero, and its previous value was less than zero. The output is false (equal to 0), when the input is negative or zero, or if the input is positive and its previous value was also positive.

6.3.5 The Detect Rise Nonnegative Block

The Detect Rise Nonnegative block determines if the input is greater than or equal to zero, and its previous value was less than zero. The output is true (not 0), when the input signal is greater than or equal to zero, and its previous value was less than zero. The output is false (equal to 0), when the input signal is less than zero, or if nonnegative, its previous value was greater than or equal to zero.

Example 6.16

We will create a model with the Detect Rise Nonnegative block to display changes in output for changes in the input.

The model is shown in Figure 6.23 and the input and output waveforms are shown in Figure 6.24.

Figure 6.23. Model for Example 6.16

In Figure 6.23, the Signal Generator block is set for a square waveform of amplitude 1 and fre-quency 0.5, the Unit Delay is included to delay the Step block one time unit, the Detect Rise Nonnegative block initial value was set to 0, and the Convert Block is used to convert the output signal of the Detect Change block from uint(8) to double. The waveforms in Figure 6.24 indicate that the output is true (not 0), when the input signal is greater than or equal to zero, and its pre-vious value was less than zero. The output is false (equal to 0), when the input signal is less than zero, or if nonnegative and its previous value was greater than or equal to zero.

Figure 6.24. Input and output waveforms for the model of Figure 6.23

6.3.6 The Detect Fall Negative Block

The Detect Fall Negative block determines if the input is less than zero, and its previous value was greater than or equal to zero. The output is true (not 0), when the input signal is less than zero, and its previous value was greater than or equal to zero. The output is false (equal to 0), when the input signal is greater than or equal to zero, or if the input signal is nonnegative and its previous value was positive or zero.

Example 6.17

We will create a model with the Detect Fall Negative block to display changes in output for changes in the input.

The model is shown in Figure 6.25 and the input and output waveforms are shown in Figure 6.26.

Figure 6.25. Model for Example 6.17