SU1667100A1 - Device for queueing system simulation - Google Patents

Abstract

The invention relates to computing and can be used in the simulation of multichannel queuing systems (QS), taking into account the dynamics and modes of operation. The purpose of the invention is to expand the functionality of the device by limiting the number of service channels that are simultaneously under maintenance. The device contains a random pulse generator, a voltage generator, a clock pulse generator, a total number meter, a summing counter, a decoder, a counter for the number of channels in service, a comparison circuit, a memory register, two OR elements, and service channels for , each of which can simulate the operating modes, servicing the demand, failures and restorations and the maintenance of the servicing instrument. 2 Il.

Description

The invention relates to computing and can be used in the simulation of multichannel queuing systems, taking into account the dynamics and modes of operation.

The purpose of the invention is to enhance the functionality by limiting the number of service channels that are simultaneously under maintenance.

1 shows a diagram of the device, where the first channel is opened; figure 2 - the same where the last channel is opened.

The device contains a generator of 1 random stream of pulses, a generator of 2 applications, K modeling channels, each of which contains a generator of 3 clock pulses, the first element OR 4, the generator 5 random intervals of operation, the first element And 6, the generator 7 random

service intervals of the order, the first differentiator common element 8, the second element AND 9, the block 10 counters, the second differentiating element 11, the third element AND 12, the generator 13 random recovery time intervals, the second trigger 14, the fourth element And 15.

In addition, the device in the last channel contains the third element OR 16, the third differentiating element 17, the first trigger 18, the fifth element AND 19, the reversible counter 20, the memory register 21, the generator 22 random maintenance time intervals, the fifth trigger 23, the ninth element And 24, the fourth differentiating element 25. the counter 26 of the total number of the application; in the last channel, the eighth element And 27, a group of elements OR 28, a group of elements And 29. the fourth trigger 30, the fifth differentiating element

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ment 31, delay element 32, seventh element AND 33, element 34, first 35 of the block of 10 counters, second input 6 of the AND 6 element, direct input 37 of the OR 4 element, output 38 of the generator 13 random recovery time intervals, generator output 39 22 random maintenance intervals. The device also contains the third element OR 40, the input 41 of the block of 10 counters, the output 42 of the generator 7, the output 43 of the element And 15, the output 44 of the element And 27, the output 45 of the element And 33, the second element OR 46, (K-1) -th output 47 decoder, (K-2) -th output 48 of the decoder connected to the second input element And 9 (K-1) -th channel, output 49 element And 62 K-th channel, output 50 element And 62 (K-1) th channel, K-th input 51 of the element OR 61, (K-1) -th input of the 52 element OR 61. The device contains a generator of 53 pulses, a totalizing counter L4, a decoder 55, the first element OR 56, a counter 57 of the number of channels found of maintenance, third trigger 58, comparison circuit 59, memory register 60, second element OR 61, eighth element AND 62, sixth element AND 63, zero output 64 of the decoder 55, output 65 of the first decoder 55, first input 66 elements OR 56, the second input 67 of the element OR 61, the output 68 of the comparison circuit 59, the first input 69 of the element OR 61, and in the last channel the ninth 70, the tenth 71 elements AND the fourth element OR 72.

The device simulates the process of operating a system that has K service channels, each of which can be in four modes (states): operation, failure, restoration, maintenance time. Servicing is done only during operation. The end of the operation mode corresponds to the occurrence of a failure, while the channel goes into recovery mode and at the same time opens the next channel to which the next application arrives. Unserved due to rejection, the application returns to the input of the ready-to-work channel.

After a certain specified time, each channel goes into maintenance mode, if the system is in a maintenance mode no more than a specified number of channels. Otherwise, the channel continues to function. Inquiries received during recovery or maintenance modes are serviced in the next channel.

The device works as follows

Generator 1 generates a pulse that triggers generator 2 for wok, a generator of 53 pulses, in each channel a generator of 3 clock pulses, and also,

passage through the element OR 4, in each channel starts the generator 5 random time intervals. The output of the generator 5 generates a random time interval corresponding to the duration of the operating mode. The outputs from the generator 2 are fed to the open element 6 and start the generator 7 random service time intervals, which forms the service time interval for the application,

5, the end of this interval is a pulse from the output of the differentiating element 8 through the element AND 9 in the presence of voltage on the generator 5 is fed to the first input of the block of 10 meters, where the total is calculated

0 the number of serviced items in the Kth channel of the system.

At the end of the time interval of operation, a pulse, imitating a failure, from the output of the differentiating element 11 through

5 and 12 starts the generator 13. At the output of the latter, a time interval is formed corresponding to the recovery mode.

The same impulse arrives at the single input of the trigger 14 and overturns it, after which the voltage from the output of the trigger 14 enters the input of the element 15. The second input of the element 15 enters the counting pulses from the generator 3, which pass

5 to the third input of a block of 10 counters, counting the channel recovery time.

At the end of the time interval recovery pulse from the output of the differentiating element 17 through the first

0 the inverse input of the element OR 4 starts the generator 5, again switching the K-th channel to the operation mode. The same pulse arrives at the zero input of the trigger 14, after which the counting pulses do not arrive at the third

5 input of the block of counters 10. The pulse from the output of the element OR 4 is also fed to the single input of the trigger 18, the output of which is applied to the first input of the element I 19, the second input of which is fed

0 counting pulses from the generator 3, and the third - a single potential from the inverse output of the trigger 58. The counting pulses are passed to the subtracting input of the reversible counter 20 and corresponding to the specified

5 time the number starts to decrease.

At the same time, the counting pulses arrive at the fourth input of the block of 10 counters, through an open element And 63. where the total residence time is calculated

system in operation mode. At the end of the operation time interval, the pulse from the output of the element 12 goes to the zero input of the trigger 18 through the element OR 40, after which the counting pulses do not pass to the counter 20 and the fourth input of the block 10 of the counters. As soon as the contents of the reversible counter 20 have a zero value, the pulse from its output goes to the single input of the trigger 58 and overturns it, closing element I 19. A single signal from the direct output of the trigger 58 goes to the input of the element 62.

The pulse generator 53 generates pulses arriving at the summing input of the summing counter 54 (counting from O to K-1), the outputs of which are connected to the corresponding inputs of the decoder 55, zero output 64 of which is connected to the second input of the And 62 element. The generator 53. summing counter 54 and a decoder 55, organizes a sequential polling of channels requiring access to the service mode.

A single signal from the output 68 of the comparison circuit 59 is supplied to the third inputs of the elements 62 of each channel, in case the number of channels in the maintenance mode is less than the allowable number of channels allowed to enter the maintenance mode. The allowable number is written to register 60 before the start of the simulation process. In the case when the maximally permissible number of channels is under maintenance, the zero signal from the output of the comparison circuit 59 locks the AND 62 element and prevents the generator 22 from starting. Otherwise, the output of the next channel to the maintenance mode is allowed and the pulse from the output of the AND 62 enters the installation input of the generator 5, starts the generator 22 and enters the first input 66 (for the first channel) of the element OR 56, from the output of which a pulse arrives at the summing input of the counter 57 channels that are in technical mode skoy service.

When a signal arrives at the installation input of the generator 5, the operation time interval ends. Since the voltage from the output of the generator 22 is applied to the inverted input of the element 12, the passage of a pulse to the generator 13 is forbidden. The pulse from the output of the element i 62 overturns the trigger 23. the voltage from the output of which is fed to the input of the element 24, to the first input which receives the counting pulses from the generator 3. The pulses are passed to the input 41 of the block of 10 counters.

where the total time the system is in maintenance mode (TS) is calculated. In addition, the pulse from the output of the element And 62 is supplied to the zero input of the trigger 58 by switching it. as well, through the element OR 40 resets the trigger 18 and the counting of the total operating time of the device is terminated.

At the end of the maintenance time interval, a pulse appears at the output of the differentiating element 25, which through the element OR 4 enters the start of the generator 5, switching the channel to the operation mode. The same pulse arrives at the zero input of the trigger 23, after which the counting pulses stop at the input of the block 10 of the counters, and also enters the input of the register 21, in which the number corresponding to the specified operating time is recorded. With the arrival of a pulse, this number is recorded in a parallel code in the reversible counter 20. In addition, the pulse from the output of differentiating element 25 passes through the OR element 61 and goes to the subtracting input of counter 57, reducing its content by one.

In the modes of operation, restoration and maintenance of the first channel from the outputs of the generator 22, 7.13, respectively, through the element OR 28 of the second modeling channel a pulse arrives at the first input of the element AND 29 of the same channel.

The second input element And 29 of the second channel receives requests from the generator 2, the request and passes to the second modeling channel for their service. Similarly, in case of failure or maintenance in the second channel, applications from generator 2 are sent to the third channel, etc.

To count the number of unserved applications received during the channel operation, during restoration or maintenance, the outputs of the generators 13 and 22 in the last channel (FIG. 2) are connected to the first and second inputs of the OR 16 element, respectively, whose output is connected to the first input element 27, to the second input of which applications are received from generator 2 that passed through element i 29. These applications will go to the fifth input of the block of 10 meters only if there is an enabling voltage at the first input of element 27 from generator 13 or 22.

Based on the meter readings, it is possible to estimate the probabilistic indicators of the service quotation.

In order to eliminate the loss of a maintenance-related application, in the event of a channel failure, an unserved application is returned to the input of the K-th channel, ready for operation, as follows. The application received in the channel for service will pass through the element 6 and onto the single input of the trigger 30, the output of which is set to a high level. At this time, the channel fails, i.e. generator 5 intervals of random pulses of work stops working. The generator 13 random recovery pulses is started. A high level from its output enters the input of the element OR 46 and, passing through it, enters the zero input of the trigger 30, the latter is set to the zero state. At the output of the differentiating element 31, a pulse is produced, since it is triggered by a cut of the pulse. This impulse will go to the input of the element And 33. The impulse, indicating that the service is served, on the element 9 does not work, as the channel has failed, therefore, a high level will be set at the output of the element 34. Through the delay element 32, it will go to the second input of the And 33 element. At the output of the And 33 element, as a result, a pulse simulating a charge is obtained. This application goes to the inputs of the service channels and re-accepts the service of the application,

Claims (1)

Claims An apparatus for simulating queuing systems, comprising a random pulse generator, the output of which is connected to the start input of the generator, the output of which is connected to the input of the total number of requests, K service simulation channels, a group of (K-1) -th the OR element, a group of (K-1) -th element AND, each service simulation channel contains from the first to the seventh elements AND, the first to fifth differentiating elements, the first, second, third, fourth triggers, the generator with Array recovery time intervals, random maintenance time interval generator, clock pulse generator, reversible counter, memory register, first and second OR elements, random time service interval generator, random time interval generator, delay element, NOT element, block counters, the K th channel of the service simulation contains the eighth element AND and the third element OR, in each channel of the service simulation the output of the first element AND is connected to the input of the input increasing the random time interval generator for servicing the order of which is connected through the first differentiating element to the inverse input of the second element AND whose output is connected to the first information input of the block counters, the output of the generator of a random stream of pulses is connected to the trigger input of the clock pulse generator and the direct input of the first OR element, the output of which is connected to the single input of the first 0 of the trigger and the start input of the random operation time generator, the output of which is connected to the first input of the first element AND, the direct input of the second element AND and the input of the second differentiating element, the output of which is connected to the first inverse of the third element AND whose output is connected to the unit the input of the second trigger and the start input of the random interval generator 0 recovery time, the output of which is connected to the input of the third differentiating element and the first input of the second element OR, the output of the third differentiating element is connected to the first progressive input of the first element OR and the zero input of the second trigger, the direct output of which is connected to the first input of the fourth element And, the second input of which is connected to the output of the clock generator 0 pulses and the first inputs of the fifth and sixth elements I, the output of the sixth element I is connected to the second information input of the counter block, the output of the fourth element I is connected to the third information input of the block of counters, the output of the random maintenance intervals is connected to the second inverse of the third element And and the input of the fourth differentiating 0 element, the output of which is connected to the second inverse input of the first element OR and the read input of the memory register, the bit outputs of which are connected to the bit inputs of the reversible counter, the output of the second element OR is connected to the zero input of the fourth trigger, the direct output of which is connected to the input of the fifth differentiating element, the output of which is connected to the first input of the seventh element And, the output of which is connected to the output of the generator, the second input of the seventh element And is connected to the output of the delay element, od connected to the output of NOT circuit whose input 5 is connected to the output of the second element AND and the second input of the second element OR, the single input of the fourth trigger is connected to the output of the first element AND, and the direct output of the first trigger is connected to the second input of the fifth element AND, whose output connected to the subtracting input of the reversible counter, the zeroing output of which is connected to the single input of the third trigger, in the K th service simulation channel the first and second inputs of the third OR element are connected to the outputs of the random maintenance time interval generator and random recovery time interval generator, and the output The third element OR is connected to the first input of the eighth element AND, the output of which is connected to the fourth information input of the counter block, the output of the generator The torus is connected to the second input of the first element AND of the first service simulation channel and the first inputs of the device elements AND groups, the second inputs of which are connected respectively to the outputs of the elements of the device OR group, the output of the 1st element AND of the device group (1 1, K-2) connected to the second input of the first element I (i + 1) -ro of the service modeling channel, and the output (K-1} of the element AND of the device group is connected to the second input of the first element And and the second input of the eighth element of the K-th service modeling channel first The input of the j-ro element OR of the group (j 1, K-1) is connected to the output of the random service time generator J-ro of the service modeling channel, the second input of the j-ro element OR group is connected to the output of the recovery time interval generator, and the third input The j-ro element of the OR group is connected to the output of the generator of time intervals for the maintenance of the J-ro service simulation channel, characterized in that. in order to extend the functionality by limiting the number of channels that are simultaneously in maintenance, it additionally contains a pulse generator, a summing counter, a decoder, two OR elements, a memory register, a comparison circuit and a counter for the number of channels being maintained, the first to (K-1) -th service simulation channels additionally contain the fifth trigger, the eighth and ninth elements AND, and the third element OR, the Kth service simulation channel additionally contains the first trigger, the ninth and tenth elements AND, and the fourth element OR, and in the service simulation channels from the first to the (K-1} -th direct output of the third trigger is connected to the first input of the eighth element I. maintenance intervals, the stopping input of the random operation time generator, the first input of the third element OR, the single input of the fifth trigger and the zero input of the third trigger, the inverse output of which is connected to the third input of the fifth element AND, the output of the third element OR is connected to the zero input of the first trigger, the direct output of which 0 is connected to the second input of the sixth element And, the output of the third element And is connected to the second input of the third element OR, the output of the fourth differentiating element is connected to the zero input of the fifth 5 flip-flops, the direct output of which is connected to the first input of the ninth element And, the second input of which is connected to the output of the clock generator, the output of the ninth element And is connected to the fourth 0 to the information input of the counter block, the second inputs of the eighth elements And are connected respectively to the outputs of the device decoder, and the third inputs of the eighth elements And are connected to the output Less of the comparison circuit, in the Km service modeling channel, the direct output of the third trigger is connected to the first input of the ninth element And, the output of which is connected to the input of the random generator 0 maintenance time intervals, random stop time generator stop input, first input of the fourth OR element, single trigger input and zero input 5 of the third trigger, the inverse output of which is connected to the third input of the fifth element AND, the output of the fourth element OR is connected to the zero input of the first trigger, the direct output of which is connected to the second input of the sixth element And, the output of the third element I is connected to the second input the house of the fourth element OR, the output of the fourth differentiating element is connected to the zero input of the fifth trigger, the direct output of which is connected to the first input of the tenth element And, the second input of which is connected to the output of the clock pulse generator the output of the tenth element I is connected to the fifth information input of the counter block, the second input of the ninth element I is connected to the corresponding output of the device decoder, and the third input of the ninth element I is connected to the output Smaller comparison circuit, the information inputs of the first and second groups of which are connected to the outputs of the memory register respectively and the bit outputs of the counter of the number of channels being maintained, the summing input of which is connected to the output of the first element of the IL AND device, the service ligation and the output of the ninth and subtractive input — with the output of the second element and the K-th channel of the simulation of the OR element, the output of the generation service is connected respectively to the pulse pa connected to the counting input of the first element OR of the device summing counter, the bit outputs 5 and the inputs of the second element OR of which the devices are connected respectively to connected respectively to the outputs of the four inputs of the decoder, the outputs of the eighth elements differentiating And all the elements of the cops of the first to (K-1) th channel mode channel simulation service. ten