SU1226488A1 - Device for calculating indicator reactions of diagram - Google Patents

Abstract

The invention relates to computing and can be used to calculate informative parameters of the resolution charts of radioactive indicators, namely the area under the rarefaction diagram and the average circulation time of the indicator. The aim of the invention is to increase the reliability by taking into account statistical amplitude fluctuations when determining the exponential portions of the diagrams. The device contains an amplitude-to-frequency converter, an integrator, a pulse distributor, reversible counters, triggers, registers, a generator of rectangular pulses, AND-OR elements, IL elements, a code-frequency converter, delay elements, AND elements, counters, and a switch. 1 il. i (L IsD Yu S 1-C oo 00

Description

The invention relates to computer technology and can be used to calculate informative parameters of the negative pressure diagrams of radioactive indicators, namely, the area under the negative pressure diagram and the average indicator circulation time.

The purpose of the invention is to increase reliability by taking into account statistical fluctuations of the amplitude when determining the exponential portions of the diagrams.

The drawing shows a block diagram of the proposed device.

The device circuit contains a converter 1 amplitude to frequency integrator 2, a distributor of 3 pulses reversible counters 4 and 5, triggers, 6-10, register 11, a generator of 12 rectangular pulses, AND-OR elements 13-17, OR elements 18-21, a code-frequency converter 22, elements 23 and 24, and elements 25 and 26, counters 27 and 28, switch 29, input 30, and device output 31.

The device works as follows.

In the initial state, the integrator 2, the counters 4,5,27,28, the triggers 6-10, the register 11 and the distributor 3 are set to the zero state. The device is started immediately after the introduction of the radioactive indicator by applying a pulse to the input 30, i.e. on the single inputs of the triggers 7 and 8, which in this case are set to one and open the AND-OR elements 13 and 14, the distributor 3 and the integrator 2. The latter begins to integrate the output signal of the converter 1 by counting the number of pulses through the AND-OR element 14 and 15 to the counting input of the integrator2, made, for example, according to the scheme of a reversible pulse counter.

The first cycle of operation of the device when the number of pulses equal to N arrives at the input of integrator 2, when the first pulse signal appears at its output, which triggers distributor 3. Next, at the first output of the distributor, there appears a temporal potential coming through the OR 18 control element the input of the addition of counter 5, which during this time

will register the average frequency of the pulses arriving at its input from the output of converter 1. Upon receipt of alternate & N pulses

to the integrator 2 input, the signal from the last output is triggered by the distributor 3, at the second output of which a temporarily resolving potential appears through the element

OR 19 to the control input of the subtraction of counter 5, wherein the second value of the average frequency of the pulses is read from the first value of the average frequency of the pulses. Since the subsequent value of the average frequency of the pulses is always greater than the previous one on the plot of the amplitude of the indicator rarefaction chart, the resulting transfer output of the counter 5

the impulse comes through the element opened in the second cycle AND 25 and the element OR 21 to the installation input of the distributor 3, setting it to the initial state.

Similarly, work also takes place in all subsequent cycles on the rise of the indicator underpressure diagram when the indicator is caddy. the comparison cycle contains two measurement cycles.

After reaching the maximum value, there is a section in the rarefaction diagram, where the average frequency of the pulses, i.e. averaged amplitude of rarefaction diagrams

the indicator begins to decrease exponentially and the distributor 3 begins to operate cyclically four measuring cycles in each cycle. In this case, in the first measurement cycle, the counter 5 works on addition, in the second and third, on subtraction, and in the fourth, again on addition.

At the end of the fourth measurement cycle of each cycle, the inequality is verified.

h (t) ut -n (t,) At-h (t,) At + h (tj)

(1) where n ({) is the value of the ordinates.

If the algebraic sum of the ordinates of the rarefaction diagram of the radioactive indicator is positive, i.e. O, then in the fourth measurement step of the ordinate n (tj), a transfer pulse appears at the output of the reversible counter 5, which is And 26, opened in this TafeTe element, then the OR element 20 arrives at the single trigger input 6.

counter 28, which starts counting the pulses Di, the number of which is determined by statistical fluctuations of the compared four ordinates of the rarefaction diagram of the radioactive indicator. If the number of these pulses is greater than the value (li and |, preset by switch 29, then at the corresponding output of counter 28 a signal appears that sets trigger 6 and counter 28 to initial state through switch 29 and the OR element. 2 arrives at the installation input of the distributor of 3 pulses, setting it also to the initial state, and starts a new comparison cycle. If the number of pulses received at the counter 28 does not exceed 1 amp and then the signal from the fourth output of the distributor3 pulses at the end of the fourth cycle enters the input of the open element AND-OR 16 and from the output of the latter to the input of the installation in the zero state of the trigger 7, as a result of which the distributor 3 pulses closes and reversible counter 4 opens.

When the algebraic sum of the four ordinates of the dilution curve is negative, i.e. uhc O, then the transfer pulse at the output of the reversible counter 5 during the fourth measurement cycle of the ordinate i- (tj) does not appear, but after the end of this cycle the falling edge starts the trigger 10 and the delay element 24 from the fourth output of the distributor 3 pulses the signal through the OR element 20 sets the trigger 6 to one state. As a result, the reversible counter 5 and the counter 28 begin to count the pulses from the generator 12, which -. The second ones arrive at their inputs through the I-IPI element 17. Moreover, if the algebraic sum (1) is in absolute value greater than the value of 1l1 set by switch 29, then the first signal appears at the corresponding output of counter 28, which is fed through switch 29 and the OR element 21 to the zero input of the trigger 10 and the installation input of the distributor 3 pulses, and a new comparison cycle begins. If the algebraic sum (1) is less in absolute value, then an impulse appears at the beginning

transfer at the output of the reversible counter. 5, which through the element AND-OR 16 enters the zero input of the trigger 7, i.e. the comparison process ends in the same way as with a positive value of the algebraic sum (1), when it is less than 1D. at this time, integrator 2 will register the total number of impulses t.

owls equal

jhCt) dt

admitted to

its input is from the start of integration to the time when inequality (1) is reached, and register 11 is the difference in the average part h (to) (t J K dM which is rewritten from counter 5 to register 11 at the beginning of the third measurement cycle when the leading edge of the resolving potential from the output of the distributor, 3 pulses are fed to the synchronization input of the register 11. In the counter 4, the number b is recorded (t which is equal to the average frequency of the pulses in the fourth measurement cycle, when the enable potential from the output of the pulse distributor enters the control input counter 4. The output of the code-frequency converter 22, whose conversion coefficient is set to 10 / AN, where b is a positive integer, appears frequency f to AN- 10 mm k-10 .kg-torus through the open half of the AND element -11PI 13 starts to arrive at the counting input of counter 4. From this point on, counter 4 works on subtraction.

Simultaneously frequency 10 s

one.

the output of generator 12 through the open half of the element AND-OR 14 begins to flow to the input of integrator 2. The pulses that appear at the output of which no longer start the distributor of 3 pulses, since the latter is closed. The integrator 2 counts the pulses with a frequency f, for a time until a signal appears at the transfer output of the counter 4, which sets the trigger 8 to the initial state. This time is determined by the number b (1), which was registered by the counter 4, and the frequency f, fed to the input of the counter 4, and is equal to {i:,) ({.. During this time, the integrator 2 to the number of pulses

 hCt) dt Calculates a number equal to, (nCtj) / i, - 10 h (t) / K1o .n (t

S

those. the content of the integrator is increased by the size of the area (in pulses) under the extrapolated frequent diagrams of the vacuum indicator and becomes equal to the total area (in impulses) under the vacuum diagram of the radioactive indicator:

g, 4. ..-- l - irО:.

At the moment of setting the trigger 8 in s, the running state of the potential from its output triggers a delay element 23, on the code of which a signal appears after a delay time t of 10-15 minutes, during which the radioactive indicator is uniformly stirred in the blood and the amplitude of the diagrams The vacuum indicator reaches a constant level. In this case, the average frequency of the pulses at the output of the transducer 1 amplitude to frequency also becomes constant in magnitude and equal. The signal from the output of the delay 23 trigger 9 is set to one state, as a result of which the integrator 2 is opened at the control input of the subtraction, the AND-OR element 15 and the counter 27, which starts to read the pulses of the frequency generator 12 { the integrator's input starts to come from the output of converter 1 through the element AND-OR pulses with a frequency that is subtracted from the number,. At the moment of complete subtraction of the number in the integrator 2 at its output of the transfer, the impulse that sets the trigger 9 to the initial state ceases, stopping the registration of the frequency Ir during the time during which the integrator is completely cleared, is determined by equality. Bro, in „,

,

where t ml "sh, .an. It is known that the ratio of the area bounded by the first wave of circulation of the radioactive indicator to the constant level of the amplitude of the dilution chart after a uniform dilution of the indicator in the blood is equal to the average circulation time of the indicator that the meter 27 registers with accuracy and the KdTopoe is the more informative parameter than the area under the dilution diagram, since it is equal to the time of the central blood circulation and is used

88

6

It is used as an independent body in assessing the performance of the heart.

In this way, the proposed device determines the basic informative parameters of the dilution charts of radioactive indicators, which are characterized not only by the zero algebraic sum of four ordinates in the exponential decay, but also when the deviation from zero (as a result of statistical fluctuations) of this sum by a certain amount whether the value of which is preset by switch 29 on the basis of the rms fluctuation b / h, 3t is the count of the number of pulses when measuring the average frequency. For example, if the value of & h is set to 36, then the probability that inequality (1) is satisfied will be equal to 0.99, which virtually eliminates inaccuracies in calculating the parameters of the rarefaction charts of radioactive indicators.

Claims (1)

Invention Formula 50 0 5 0 5 A device for calculating the parameters of the indicator vacuum charts, comprising an amplitude-to-frequency converter whose output is connected to the first inputs of the first, second and third AND-OR elements, a first reversible counter, the information output of which is connected to the information input of the register, the first and second triggers, whose single inputs are connected with the device start input, single} the output of the first trigger is connected to the integrating control input, the information output of which is connected to the start input the pulse distributor, the first code of which is connected to the first input of the first OR element and the x insertion input of the first reversible counter, the second output of the pulse distributor is connected to the first inputs of the first AND element and the second OR element, the output of which is connected to the subtracting control input of the first reverse the counter, the transfer point of which is connected to the second input of the first element And, the third output of the pulse distributor is connected to the second input of the second element OR and to the synchronization input of the register, The output of which is connected to the input of the code-frequency converter, the fourth output of the pulse distributor is connected to the installation input and to the control input of the second reversible counter and the second input of the first OR element, the output of which is connected to the control input of the first reversible counter, zero output The second trigger is connected to the second inputs of the first and second AND-OR elements and to the subtraction control input of the second reversible counter, the transfer output of which is connected to the zero input of the first about the trigger, the unit output of the second trigger is connected to the enable input of the distributor pulses and to the third inputs of the first and second AND-OR elements, the fourth inputs of which are connected respectively to the outputs of the code-frequency converter and the square pulse generator, the output of the first element, AND-OR connected to the counting input of the second reversible counter, the zero output of the first trigger is connected to the input of the first delay element whose output is connected to the single input of the third trigger, the zero input of which is connected En with the integrator characteristic output, the control subtraction input of which is connected to the single output of the third flip-flop with the enable input of the first counter and the second input of the third I-ShW element, the counting input of the first counter is connected to the generator output of the rectangular pulses, the zero output of the third trigger is connected to the third input of the third element AND-OR, the fourth input of which is connected to the output of the second element AND-OR, and the output to the information inputs of the integrator, the output of the first counter is the output of the device, in order to increase reliability by taking into account statistical amplitude fluctuations in determining the exponential portions of the diagrams, the second delay element, the second And element, the third and fourth OR elements, fourth and fifth triggers, fourth and fifth AND-OR elements, a switch and a second counter, the enable input of which is connected to the fourth trigger output and the first and second inputs of the fourth AND-OR element whose output is connected to zero the second trigger input, the third input of the fourth element AND-OR is connected to the transfer output of the first reversible counter and the first input of the second AND element, the output of which is connected to the first input of the third OR element, to the second input which is connected to the output of the second the delay element, the input of which is connected to the fourth input of the fourth element AND-OR, with the second input of the second element AND, with a single input the fifth trigger and the fourth output of the pulse distributor, whose setup input and the zero input of the fifth trigger are connected to the output of the fourth OR element connected by the first input to the output of the first element AND, the single and zero outputs of the fifth trigger are connected respectively to the first and second inputs of the second of the element AND-OR, the third and the fourth inputs of which are connected respectively to the output of the transducer of amplitude to frequency and to the output of the generator of rectangular pulses, the output of the fifth element AND-OR connected to the counting inputs of the first reversible counter and the second counter, the outputs of the bits of which through the switch are connected to the second input of the fourth OR element, to the installation input of the initial state neither the second counter and the zero input of the fourth trigger, whose single input is connected to the output of the third element OR.