SU1651282A1 - Device for shaping random samples - Google Patents

Abstract

This invention relates to automation and computing. The purpose of the invention is to expand the class of tasks to be solved by ensuring the formation of a random sample of a given volume from a sample of any volume. The device contains a noise generator 1, voltage dividers 2, 9, switches 3.10, decoders 4.11, counters 5, 12, reference element 6, element OR 7, reference voltage source 8. 1 il.

Description

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The invention relates to automation and computing and can be used in static modeling and for controlling the procedure for extracting a random sample from a certain sequence of objects, in particular in the practice of selective control of product quality.

The purpose of the invention is to expand the class of tasks to be solved by ensuring the formation of a random sample of a given volume from a sample of any volume.

The drawing shows a functional diagram of the device.

In the proposed device, each signal. Interrogation from a sequence of N signals causes the appearance of an output signal at the first output of the device with a conditional probability.

PH / O-jsr TTT

where I T, the sequence number of the signal in the sequence of the N signal Poll;

I - number of signals Poll from previous (And) signals Poll that caused the appearance of the output signal at the first output of the device.

Accordingly, each interrogation signal causes the output signal to appear at the second output of the device with the conditional probability PaO / l) I - PiO / t) As a result of the device functioning according to this algorithm, a sequence of N interrogation signals will cause exactly n output signals at the first output devices, at the second output - respectively (Nn) output signals. In addition, each of the various sets of N over n different signals. A survey that caused the appearance of n output signals at the first output of the device has

one

CR number of combinations of N elements on o.

The unconditional probability that the signal from the sequence of N polling signals causes the output signal to appear at the first output of the device is the same for any i-th signal from the Poll signal sequence and

equals P (f) - -J-J

Thus, the device makes it possible to simulate a random sample of a given volume n of a certain sequence of N objects.

The device contains a noise generator 1, the first divider 2 voltage, the first

equal probability P

where CRi switch 3, first decoder 4, first counter 5, reference element 6, element OR 7, voltage source 8, second divider voltage 9, second switch 10, second decoder 11 and second counter 12.

The device works as follows.

The noise generator 1 has a voltage at its output, the instantaneous values of the amplitudes of which are evenly distributed in the interval from 0 to Um. In the output of the noise generator 1, the voltage is applied to divider 2

voltage, on the t-th output of which it is also uniformly distributed in the interval

from 0 to Um, HjS. (N-i +1), where I - Shch With 1st

the output of the divider 2 through the switch 3, the noise voltage is applied to the first input of the comparison element 6. Accordingly, the source 8 of the reference voltage has

its output voltage Uon -5- Um C

the output of source 8, the voltage is applied to the second divider 9, at the 1st output of which

it is equal to Ui (pI-1), where t 1, p + 1, C 1

the output of the second divider 9 through the second

the switch 10, the voltage Ui is applied to the second input of the comparison element 6; every 1st interrogation pulse from a sequence of pulses Polling is sent to the counting input of the counter 5. it increases

the contents per unit, which causes the control signal from the decoder 4 to be fed to the input of switch 3. Accordingly, switch 3 switches the noise voltage Umi from its 1st output to divider 2 to its output. Thus, upon the arrival of each interrogation pulse in element 6 comparison, the voltage of the output of the first switch 3 is compared with the voltage Ui from the second

switch 10. If Umi Ui, on the second

The output of the reference element 6 is a signal pulse. If Umi Ui, a signal pulse appears at the first output of the comparison element 6, after which it

enters through the OR circuit 7 to the counting input of the second counter 12. Each pulse arriving at the counting input of counter 12 increases its content by one, which causes the control signal from the decoder 11 to enter the second switch 10. Accordingly, the switch 10 switches to its output voltage Ui from the new output of divider 9, the voltage value on which is high

a rank equal to -rr-, less than the previous one,

After the N-ro polling pulse state, the counter 5 is zeroed. The zero state of the counter 5 causes the flow from the decoder 4 to the switch 3 of such a control signal when the output of the switch 3 receives the full voltage value of the noise generator 1. At the same time, an overflow pulse from the output of counter 5, fed through the circuit OR 7 to the input of the second counter 12, causes the latter to be reset. As a result, the output of the second switch 10 receives the full value

voltage um source 8 from first

output divider 9 voltage. Thus, after the arrival of N polling pulses, the device returns to its original state.

Claims (1)

Apparatus of the Invention A random sample generator comprising a noise generator, a reference voltage source, a first voltage divider, a first switch, a reference element, a first decoder, a first counter, the counting input of the first counter being the device polling input, the output of the first counter connected to the input of the decoder, the group of outputs of which is connected to the group of the corresponding control inputs of the first the switch, the group of information inputs of which is connected to the group of corresponding outputs of the first voltage divider, whose input is connected to the output of the noise generator, the output of the first switch is connected to the first input of the comparison element, characterized in that, in order to expand the class of solved tasks by providing random sampling of a given volume from a sample of any volume; the second voltage divider, the second switch, the second decoder, the second counter, the OR element, are additionally introduced into it; the first input of which is connected to the overflow output of the first counter, the output The smaller comparison element is connected to the second input of the element, OR is the output of the first sample of the device, the output More comparison item is the output of the second sample device, the output of the OR element is connected to the counting input of the second counter, the output of which is connected to the input of the second decoder, the output group of which is connected to the group of corresponding control inputs of the second switch, the information input groups of which are connected to the group of corresponding outputs voltage divider, whose input is connected to the output of the voltage source, the output of the second switch is connected to the second input of the reference element.