Summary of the invention
The object of the invention is to overcome the shortcoming of above-mentioned prior art, provide a kind of improvement GA based on polychromatic sets hierarchical structure to solve the method for Flexible Workshop scheduling, the method has been introduced multi-level constraint specification method, by original huge circuit matrix cutting, reduce the redundant data amount of restricted model, increased the possibility of algorithm practical application; Improve in addition chromosomal coded system, removed a large amount of amorphs, from the further optimized algorithm of space complexity angle, improved speed of convergence.
For achieving the above object, the technical solution used in the present invention comprises the following steps:
1) set up the mathematical model of Markov chain;
2) set up the Job-Shop restricted model based on PST hierarchical structure;
3) according to operation-benchmark, benchmark-device numbering, device numbering-asset number circuit Boolean matrix, generating process-equipment real number circuit matrix, and then produce hereditary recessive code sequence list, the corresponding lathe coding of row mark, the corresponding recessive gene of rower position; Wherein, the process time that in table, content is operation, the operation numbering of the corresponding workpiece of recessive gene code bit, by searching for corresponding operation-benchmark, benchmark-device numbering, device numbering-asset number circuit Boolean matrix, thus find the lathe coding corresponding to certain working procedure, according to the availability aspect of lathe, select corresponding lathe coding as chromosomal dominant coding again.
In described step 1), the concrete grammar of setting up the mathematical model of Markov chain is:
FJSP can be described to, and supposes that M is the quantity of process equipment, and N is workpiece to be processed quantity, and P is process number, the set that I is all devices; I
egrepresent the available devices set of the g procedure of workpiece e,
j
eprocess number for workpiece e; X is the process sequence of all workpiece, S
egkthe start time that the g procedure of expression workpiece e is processed on equipment k; E
egkfor the g procedure of the workpiece e process finishing time on equipment k; T
egkfor the g procedure of workpiece e lasting process time on equipment k, and k ∈ I
egthere is E
egk=S
egk+ T
egk; E
pthe completion date that represents finishing operation; MS represents the last completion date of all workpiece;
When the j procedure of workpiece i and the g procedure of workpiece e are carried out on same equipment, if operation j adds man-hour prior to operation g, Q
ijeg=1, otherwise Q
ijeg=0; If the g procedure of workpiece e is processed on lathe k, X
egk=1, otherwise X
egk=0;
If certain FJSP has the possible processing sequence of S kind, require total the shortest Machining Sequencing of activity duration, first ask for each processing sequence x (x ∈ 1 ..., S}) the corresponding activity duration; Obviously, in order x, the i.e. last completion date of all workpiece of the completion date of last manufacturing procedure, has
MS=E
p (1)
Objective function F (x) is
F(x)=min(MS
x)=min((E
p)
x) (2)
X=1,…,S
S.T.S
egk-E
e(g-1)n≥0
e=1,…,N;g=1,…,J
e;X
egk=1,X
e(g-1)n=1 (3)
S
egk-E
igk≥0
e=1,…,N;g=1,…,J
e;X
ijk=1,X
egk=1,Q
ijeg=1 (4)。
Described step 2), in, the restriction relation of Job-Shop restricted model is:
First equipment benchmark is set, several unit types that each equipment benchmark comprises process similarity, each unit type comprises again the concrete equipment of several this kind of models, every concrete equipment is corresponding with corresponding asset number again, and operation finally will complete processing on concrete equipment, therefore just can be by the restriction relation of operation and benchmark, the restriction relation of equipment benchmark and unit type, the restriction relation of unit type and asset number, indirectly set up the restriction relation of operation and concrete equipment, thereby realize huge operation lathe circuit matrix is divided into little relational matrix, to reduce scale and the data volume of matrix, improve the speed that solves of algorithm.
In described step 3), according to the availability aspect of lathe, select corresponding lathe coding to be specially as chromosomal dominant coding:
3.1) set up the restricted model based on hierarchical structure circuit Boolean matrix:
Use the hierarchical structure circuit Boolean matrix of benchmark and unit type, unit type and asset number, auto-correlation, process equipment, process equipment real number as restricted model, produce hereditary recessive code sequence list, the operation of GA is all carried out in the scope of restricted model;
3.2) chromosomal coding:
3.3) chromosomal decoding:
According to the corresponding information of chromosome the inside, search technique-equipment real number circuit matrix, determines parameter process time of all process steps on each lathe;
3.4) select operation:
The corresponding chromosome of individuality that fitness value in previous generation population is best is directly selected to enter population of future generation;
3.5) interlace operation:
Two parent chromosomes of random selection, two random number 0<a<b<N, wherein, N is chromogene number, finds out corresponding a on two parent chromosomes, the fragment between b exchanges each other;
3.6) variation.
The concrete grammar of described chromosome coding is:
First determine effective process number sum that chromosome length is each workpiece:
(a) when being the production model of the many kinds of single-piece:
Have each of n class workpiece, GA chromosome length is
l wherein
gprocess number for corresponding g part;
(b) when being the pattern of variety production more than many:
There is n class workpiece J part J=n altogether
1+ n
2+ ...+n
i+ ...+n
n, n wherein
1, n
2..., n
i..., n
nthe quantity i ∈ n that represents respectively i class workpiece, every class workpiece has p
iprocedure, needs first the process sequence of workpiece to be encoded, and workpiece process sequence is carried out randomly ordered, generates dominant chromosome;
When the quantity of part of the same race is less than 100, be merged into a task; Finally, according to benchmark and unit type, unit type and asset number circuit matrix, generate recessive chromosome;
When quantity employing over 100 of part of the same race strategy in batches, between the individual task body after in batches, be randomly ordered.
The concrete grammar of described variation is:
3.6.1) set aberration rate, determine the gene position that needs variation;
3.6.2) search benchmark and unit type, unit type and asset number circuit matrix, find this gene position can replace the coding of lathe, produces new chromosome;
3.6.3) calculate new chromosomal objective function, the target function value that new and old chromosome is corresponding, and then select preferably to enter the next generation.
Compared with prior art, the present invention has following beneficial effect:
The present invention is according to operation-benchmark, benchmark-device numbering, and device numbering-asset number circuit Boolean matrix, generating process-equipment real number circuit matrix, and then produce hereditary recessive code sequence list, the corresponding lathe coding of row mark, the corresponding recessive gene of rower position; Wherein, the process time that in table, content is operation, the operation numbering of the corresponding workpiece of recessive gene code bit, by searching for corresponding operation-benchmark, benchmark-device numbering, device numbering-asset number circuit Boolean matrix, thus find the lathe coding corresponding to certain working procedure, according to the availability aspect of lathe, select corresponding lathe coding as chromosomal dominant coding again.Improvement GA algorithm of the present invention is all at operation-benchmark in the random implementation of coding, decoding and variation, benchmark-device numbering, in device numbering-asset number circuit matrix restraint, carry out, random in a kind of controlled range, its role is to reduce the data volume of restricted model and removed invalid information and dwindled the hunting zone of solution space, finally having improved Algorithm for Solving precision and speed.
Further, chromogene of the present invention position coding method, has removed amorph position, has reduced space and the time complexity of algorithm, thereby improves the search efficiency of GA.
Embodiment:
1) mathematical model of Markov chain
FJSP can be described to, and supposes that M is the quantity of process equipment, and N is workpiece to be processed quantity, and P is process number, the set that I is all devices; I
egrepresent the available devices set of the g procedure of workpiece e,
j
eprocess number for workpiece e; X is the process sequence of all workpiece, S
egkthe start time that the g procedure of expression workpiece e is processed on equipment k; E
egkfor the g procedure of the workpiece e process finishing time on equipment k; T
egkfor the g procedure of workpiece e lasting process time on equipment k, and k ∈ I
egthere is E
egk=S
egk+ T
egk; E
pthe completion date that represents finishing operation; MS represents the last completion date of all workpiece;
When the j procedure of workpiece i and the g procedure of workpiece e are carried out on same equipment, if operation j adds man-hour prior to operation g, Q
ijeg=1, otherwise Q
ijeg=0; If the g procedure of workpiece e is processed on lathe k, X
egk=1, otherwise X
egk=0;
If certain FJSP has the possible processing sequence of S kind, require total the shortest Machining Sequencing of activity duration, first ask for each processing sequence x (x ∈ 1 ..., S}) the corresponding activity duration; Obviously, in order x, the i.e. last completion date of all workpiece of the completion date of last manufacturing procedure, has
MS=E
p (1)
Objective function F (x) is
F(x)=min(MS
x)=min((E
p)
x) (2)
X=1,…,S
S.T.S
egk-E
e(g-1)n≥0
e=1,…,N;g=1,…,J
e;X
egk=1,X
e(g-1)n=1 (3)
S
egk-E
igk≥0
e=1,…,N;g=1,…,J
e;X
ijk=1,X
egk=1,Q
ijeg=1 (4)
2) the FJSP restricted model based on PST hierarchical structure
2.1 polychromatic sets theory brief introductions
Polychromatic sets theory is the mathematical tool that a new systematic modeling theory and help information are processed, and this theory and method are in USSR (Union of Soviet Socialist Republics) and present Russian business circles after occurring, particularly Aero-Space enterprise has obtained propagation and employment widely.This theoretical core thought is in the different object of emulation (product, production system, design and processes process etc.) by identical the application of mathematical model, hierarchical structure between descriptive element and complex relationship, and at set layer and logical layer tissue and process information, in number of layers, process low layer data actual value problem.
2.2 workshop actual production constraint conditions are analyzed
For general manufacturing enterprise, actual production work meeting is subject to impact and the restriction of the factors such as a large amount of people, machine, material, method, ring, therefore the many factors that actual Job-Shop need of work is considered, with common PST, describe this restriction relation, can cause the circuit matrix of individual color, unified color and body all to there is larger data volume.How many-sided impact can be altered in the middle of the circuit matrix of descriptive element relation in time, be the important bottleneck that employing multicolor sets theory and intelligent algorithm solve scheduling problem.The hierarchy Model of PST is for the effective way that provides of this bottleneck is provided.
Practical experience analysis in conjunction with a large amount of Job-Shops is found, if relevant device benchmark and unit type are set to the equipment in workshop, can operation be carried out associated with equipment benchmark order, equipment benchmark carries out associated with device code, device code carries out associated with the asset number of the concrete equipment in workshop again, finally indirectly set up operation and equipment corresponding relation, and then bring convenience to equipment control and the Job-Shop work of enterprise.If with a single circuit matrix description operation and the corresponding relation of equipment, will certainly cause matrix excessive, and lack practicality.
2.3 Job-Shop restricted models based on PST hierarchical structure
Based on above-mentioned analysis, consider various influence factors in the actual production of workshop, the present invention is provided with four kinds of constraints in scheduling process: operation retrains and refers to according to actual processing technology, and operation must be carried out scheduling according to sequencing; Benchmark constraint refers to that a procedure can only process on the equipment of several benchmark types of appointment; Lathe constraint refers to the corresponding several fixing lathe models of each benchmark type; Unique constraint refers to that any operation of each workpiece can only process at fixed time on a machine.First its restriction relation for arranging equipment benchmark, several unit types that each equipment benchmark comprises process similarity, each unit type comprises again the concrete equipment of several this kind of models, every concrete equipment is corresponding with corresponding asset number again, and operation finally will complete processing on concrete equipment, therefore just can be by the restriction relation of operation and benchmark, the restriction relation of equipment benchmark and unit type, the restriction relation of unit type and asset number, indirectly set up the restriction relation of operation and concrete equipment, thereby realize huge operation lathe circuit matrix is divided into little relational matrix, to reduce scale and the data volume of matrix, improve the speed that solves of algorithm, its concrete hierarchical structure as shown in Figure 1.
In Fig. 1, upper left corner circuit matrix has reflected operation constraint and the reference device type constraint of part, and which reference device type each procedure can be processed by, can reflect by this matrix, without cannot processing of value.Upper right corner circuit matrix has reflected the lathe constraint of reference device type with concrete unit type.Wherein have 1, prove that this reference device type comprises this unit type.Below circuit matrix has reflected the corresponding relation of M workshop appliance model with concrete lathe, wherein the process time of the corresponding operation of numeric representation on this lathe.Can further draw its Task Assignment Model as shown in Figure 2 on this basis.
FJSP by 3 workpiece is introduced to the process of establishing of its PST hierarchical structure restricted model below, its processing tasks information table is as shown in table 1, wherein facility information is shown in list, line display workpiece process information, the capable corresponding operation of data representation in table is in the process time being listed as on corresponding lathe, relevant information and resemble process criterion for table 1 arrange equipment benchmark J1, J2, J3, unit type is S1, S2, S3, asset number M1, M2, M3, M4, M5, M6, be 6 equipment of this processing, its restriction relation is each other suc as formula (5), (6) shown in.
Table 1 processing tasks information table
C wherein
ijthis point of some bit representation unit type that laterally benchmark of representative comprises.From this matrix, can find the relation between benchmark and unit type.
C wherein
ijthe asset number of all devices in corresponding this workshop of unit type that=1 some bit representation laterally represents.
The autocorrelation matrix [F (a) * F (a)] that to sum up can obtain node set is as following table 2:
Table 2[F (a) * F (a)]
According to equipment benchmark corresponding to the workpiece of table 1 related data and setting and table 2[F (a) * F (a)] middle each internodal relation recording, can obtain circuit matrix [A * F (A)] and body circuit battle array [A * A (F)] as shown in Table 3 and Table 4.Wherein F1-F6 represents different technique title car, pincers, boring, boring, milling, plane; J1, J2, J3 represent respectively three kinds of different equipment benchmark.And corresponding one by one with operation in this example.A1-a15 represents the operation row of 3 workpiece; M1-M6 represents lathe to be processed.Wherein, C
ij=1 point represents that horizontal ordinate representative element and ordinate representative color contact directly.
Table 3 technique-equipment boolean circuit matrix [A * F (A)]
Table 4[A * A (F)] in real part matrix can be used as the foundation of further recessive chromosome coding.By this matrix, can obtain processing the equipment of each operation and add the needed time of cost order work at this equipment.
Table 4 technique-equipment real number circuit matrix [A * A (F)]
Generate based on this hereditary recessive code sequence list as shown in table 5, the corresponding lathe coding of row mark, the corresponding recessive gene of rower position, the process time that in table, content is operation, the operation numbering of the corresponding workpiece of recessive gene code bit, search for relative operation-benchmark, benchmark-device numbering, device numbering-asset number circuit matrix, thereby find the lathe coding corresponding to certain working procedure, according to the availability aspect of lathe (taking or the free time), select suitable lathe coding as chromosomal dominant coding again.
The hereditary recessive code sequence list of table 5
3) operation of the improvement GA under hierarchical structure restricted model
As shown in Figure 7, Fig. 7 is improved genetic algorithms method process flow diagram of the present invention;
3.1 restricted models based on hierarchical structure circuit Boolean matrix
The hierarchical structure circuit Boolean matrix of the improved GA use benchmark of the present invention and unit type, unit type and asset number, auto-correlation, process equipment, process equipment real number is as restricted model, the operation of GA is all carried out in the scope of restricted model, and concrete operations are as follows.
3.2 chromosomal codings
First determine effective process number sum that chromosome length is each workpiece
(a) when being the production model of the many kinds of single-piece: have each of n class workpiece, the present invention improves GA chromosome length and is
l wherein
gfor the process number of corresponding g part, the workpiece number that n is this batch of scheduling, with 3 * 6 separate room above, being scheduling to example, to generate chromosome as follows:
1 |
5 |
4 |
3 |
4 |
6 |
2 |
3 |
4 |
2 |
6 |
3 |
1 |
2 |
4 |
1 |
1-6 represents the machining tool information of workpiece 1; 7-11 represents the machining tool information of workpiece 2; 12-15 represents the machining tool information of workpiece 3.
(b) when being the pattern of variety production more than many:
When for many variety production pattern: have n class workpiece J part (J=n altogether
1+ n
2+ ...+n
i+ ...+n
n, n wherein
1, n
2..., n
i..., n
nthe quantity i ∈ n that represents respectively i class workpiece), every class workpiece has p
iprocedure, needs first the process sequence of workpiece to be encoded, and if any each 3 of A, B, C class workpiece, first workpiece process sequence is carried out randomly orderedly, generates dominant chromosome.
From learning curve theory, repetitive operation can increase the proficiency of employee's operation, shortens the process time of single part, so adopt in research of the present invention with kind part, closes batch production coding strategy.When the quantity of part of the same race is less than 100, be merged into a task.Above-mentioned example can encode as follows (A*3 represent its each operation process time all corresponding this coefficient that is multiplied by, i.e. this part number).
A
11·3
|
… |
A
1m·3
|
B
11·3
|
… |
B
1m·3
|
C
k1·3
|
… |
C
km·3
|
Finally, according to benchmark and unit type, unit type and asset number circuit matrix, generate recessive chromosome.
If surpass 100, employing is strategy in batches, because if the quantity of a workpiece is too many, can affect the processing of subsequent parts after synthetic one batch.Because be different the delivery date of each batch of inner parts, so also can arrive and specify storehouse at the delivery date of regulation in order to meet other part, for example, get 100 conduct critical points in batches.If 150 of A workpiece, 211 of B workpiece, 50 of C workpiece:
A·100 |
C·50 |
B·100 |
B·11 |
A·50 |
B·100 |
Between the individual task body in batches, be randomly ordered.
3.3 chromosomal decodings
According to the corresponding information of chromosome the inside, the hereditary recessive code sequence list of search list 5, determines the parameters such as process time of all process steps on each lathe.
3.4 select operation
The corresponding chromosome of individuality that fitness value in previous generation population is best is directly selected to enter population of future generation.
3.5 interlace operation
Two parent chromosomes of random selection, two random number 0<a<b<N (N is chromogene number), find out corresponding a on two parent chromosomes, and the fragment between b exchanges each other.
3.6 variation
3.6.1 set aberration rate, determine the gene position that needs variation.
3.6.2 search for operation-benchmark, benchmark and unit type, unit type and asset number circuit matrix, find the coding of the replaceable lathe of this gene position, produce new chromosome.
3.6.3 calculate new chromosomal objective function, the target function value that new and old chromosome is corresponding, and then select preferably to enter the next generation.
According to operation-benchmark, benchmark-device numbering, device numbering-asset number circuit Boolean matrix, generating process-equipment real number circuit matrix, and then produce hereditary recessive code sequence list, the corresponding lathe coding of row mark, the corresponding recessive gene of rower position; Wherein, the process time that in table, content is operation, the operation numbering of the corresponding workpiece of recessive gene code bit, by searching for corresponding operation-benchmark, benchmark-device numbering, device numbering-asset number circuit Boolean matrix, thus find the lathe coding corresponding to certain working procedure, according to the availability aspect of lathe, select corresponding lathe coding as chromosomal dominant coding again.Improvement GA algorithm of the present invention is all at operation-benchmark in the random implementation of coding, decoding and variation, benchmark-device numbering, in device numbering-asset number circuit matrix restraint, carry out, random in a kind of controlled range, its role is to reduce the data volume of restricted model and removed invalid information and dwindled the hunting zone of solution space, finally having improved Algorithm for Solving precision and speed.Chromogene of the present invention position coding method, has removed amorph position, has reduced space and the time complexity of algorithm, thereby improves the search efficiency of GA, and concrete data can be drawn by table 3.
Principle of the present invention:
Genetic algorithm belongs to a kind of of evolution algorithm (Evolutionary Algorithms), by the heredity of natural imitation circle and the process of selection, finds optimum solution.Be applicable to solving of challenge, be now widely used in the middle of the research of every field.But from the angle of optimized algorithm and the angle of request for utilization, academia did not always all stop the improvement of this algorithm and optimization, reduce time and the space complexity of algorithm.
The optimization direction of algorithm
Single layer coding mode, can reduce the space complexity of genetic coding to a certain extent; When processing lot size scheduling problem, product type is carried out to binary encoding as one section of chromosome, each operation of product is to embody in circuit matrix with recessive chromosome segment simultaneously.
Although single layer coding mode has certain superiority, be conducive to scheduling and carry out, in chromosome, there is a large amount of amorph positions.Because it is defined as max (m by chromosome length
i) * n(max (m
i) the maximum process number that comprises for n class workpiece).So just make whole chromosomal length be decided by a great extent a workpiece of process number maximum in each batch of task.The long efficiency of genetic algorithm in iterative process that directly affected of chromosome, has increased the space complexity of algorithm.
The optimization of single layer coding
1) chromosome length optimization
Chromosome length of the present invention is
l wherein
gfor the process number of corresponding part, the workpiece number that n is this batch of scheduling.
Before improvement (with 3 parts, maximum process number is 6 for example):
1 |
4 |
6 |
7 |
0 |
0 |
2 |
3 |
4 |
0 |
0 |
0 |
1 |
3 |
5 |
1 |
7 |
3 |
After improvement:
1 |
4 |
6 |
7 |
2 |
3 |
4 |
1 |
3 |
5 |
1 |
7 |
3 |
From above, can find that only the chromosomal length of three workpiece has just had remarkable shortening.From algorithm optimization angle, when mass data, can reduce significantly the space complexity of algorithm.The present invention is improved to rear algorithm and its contrast is as shown in table 6.
The contrast of table 6 algorithm optimization
Wherein, G represents the genetic algebra of genetic algorithm; Initialized chromosome number in Z mating pond; m
iit is the process number that i class workpiece comprises; M is number of devices; J is reference device number (much smaller than physical device number).
2) close according to the actual requirements and criticize
During the scheduling of kind more than many: suppose that n class workpiece has j part (J=n
1+ n
2+ ...+n
i+ ...+n
n, n wherein
1, n
2..., n
i..., n
nrepresent respectively the quantity of i class workpiece, and i ∈ n), then establish every class workpiece and have p
iprocedure.
The mode of available technology adopting is as follows, if any each 3 of A, B, C class workpiece, workpiece process sequence is carried out randomly orderedly, generates dominant chromosome.
According to operation-lathe circuit matrix, generate recessive chromosome again.A wherein
11for the first operation of category-A product, by that analogy.As shown in the table.
A
11 |
… |
A
1m |
C
11 |
… |
C
1m |
A
21 |
… |
A
2m |
… |
C
k1 |
… |
C
km |
From learning curve theory, repetitive operation can increase the proficiency of employee's operation, shortens the process time of single part, so adopt in the present invention with kind part, closes batch production coding strategy.When the quantity of part of the same race is less than 100, be merged into a task.The above-mentioned example following A*3 that can encode represents corresponding this coefficient that is multiplied by, i.e. this part number of its each operation process time.
Finally, according to operation-lathe circuit matrix, generate recessive chromosome.
A
11·3
|
… |
A
1m·3
|
B
11·3
|
… |
B
1m·3
|
C
k1·3
|
… |
C
km·3
|
If surpass 100, employing is strategy in batches, because if the quantity of a workpiece is too many, can affect the processing of subsequent parts after synthetic one batch.Because be different the delivery date of each batch of inner parts, so also can arrive and specify storehouse at the delivery date of regulation in order to meet other part, according to practical experience, get 100 conduct critical points in batches.If 150 of A workpiece, 211 of B workpiece, 50 of C workpiece:
A·100 |
C·50 |
B·100 |
B·11 |
A·50 |
B·100 |
Between the individual task body in batches, be randomly ordered.
Case Simulation
Example 1 emulation:
Example for table 1, the parameter that genetic algorithm is set is as follows: Population Size is 50, crossing-over rate is 0.6, aberration rate is 0.8, and maximum evolution is with severally 100, carries out emulation under MATILAB7.0 environment, obtain its GA evolution curve as shown in Figure 3, this improved GA algorithm can be when 70 generation as shown in Figure 3, converges to quickly 134 from 147, and its corresponding scheduling result Gantt chart as shown in Figure 4.
Example 2 emulation and comparison:
For further verification algorithm correctness, select example 2 to carry out emulation, 2 technological datums are set, 4 device numberings, 8 concrete equipment, obtaining optimum solution is 121 minutes.From the genetic evolution curve of Fig. 5, this improved genetic algorithm can be when 32 generation, converge to 121 from 130 soon, and its speed solving is obviously very fast, and its corresponding scheduling result Gantt chart as shown in Figure 6.
Example 3 emulation and comparison:
For comparing more all sidedly and verification algorithm effect.At CPU frequency 2.5G, inside save as on the computing machine of 512MB, take VB6.0 as development platform, 8 * 8 examples of choosing the Kacem benchmark problem the inside of job shop scheduling problem solve, and 2 technological datums are set, 4 device numberings, 8 concrete equipment, calculate 10 times.Table 7 is for algorithm of the present invention is by acquired results and the solving result contrast that is minimised as evolution algorithm (Approach by Localization & Controlled Genetic Algorithhm, AL+CGA), the MS master-slave genetic algorithm of apportion model, multistage genetic algorithm, ant group genetic algorithm with part.
Each method solving result contrast of table 7Kacem8 * 8 benchmark problem
For the larger deficiency of redundant data amount in the restricted model of traditional polychromatic sets theory improved genetic algorithms method and chromosome, the present invention further proposes to use polychromatic sets hierarchy Model to improve the restricted model of algorithm, by apparatus for establishing benchmark, operation constraint is set, facility constraints, lathe constraint, the mode of unique constraint, original operation-lathe circuit matrix is divided into benchmark and unit type, the relational matrix of unit type and asset number, greatly reduce the redundant data amount of restricted model, in addition by the reasonably optimizing of chromosome length with the batch operation that closes of benchmark is in batches set, effectively reduced chromosomal Time & Space Complexity, also improved the dynamic response of algorithm model simultaneously, the finally result comparison of the emulation by identical example, the improvement GA that has proved PST hierarchical structure is having raising compared with the improved GA of traditional PS T aspect solving precision and speed, simultaneously also by selecting the experiment of Kacem8 * 8 benchmark example on identical configuration computing machine, the various performances that proved algorithm of the present invention all more traditional various algorithms are improved, further proved that algorithm is in the practicality and the superiority that solve aspect Flexible Job-shop Scheduling Problems.
Above content is only explanation technological thought of the present invention; can not limit protection scope of the present invention with this; every technological thought proposing according to the present invention, any change of doing on technical scheme basis, within all falling into the protection domain of the claims in the present invention book.