Integrated scheduling method based on improved Floyd algorithm

Abstract

The invention provides a comprehensive scheduling method based on an improved Floyd algorithm. The method comprises the following steps: firstly, establishing a complex product one-way path process tree graph according to a Floyd algorithm, and taking the processing time of a next procedure as a path weight between adjacent nodes, namely a weight value of the adjacent nodes on a one-way path; then, a root node of the one-way path process tree graph serves as a starting point, leaf nodes with low priority from the root node to a layer are established, and if the leaf nodes with the low priority are not unique, the leaf nodes with short processing time are selected to establish a path. According to the method, the optimization effects that the total machining time of complex products is shorter, and the overall utilization rate of equipment is higher are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of computer integrated manufacturing, and in particular relates to a comprehensive scheduling method based on an improved Floyd algorithm. Background Art

[0002] Intelligent manufacturing is the core technology and main line for my country's manufacturing industry to transform from big to strong, and is an important task for promoting new industrialization. At the same time, it is the key for my country's manufacturing industry to keep up with the world's development trends and achieve transformation and upgrading. At present, for a long period of time, to promote intelligent manufacturing, we must be based on the essence of manufacturing, closely follow the intelligent characteristics, take technology and equipment as the core, take data as the basis, rely on manufacturing units, workshops, factories, supply chains and other carriers, and build a knowledge-driven, dynamically optimized, safe and efficient intelligent manufacturing system to promote the digital transformation, networked collaboration, and intelligent transformation of the manufacturing industry.

[0003] In order to better solve the manufacturing needs of single-piece products and multi-variety small-batch products with strict constraints in a tree structure, a comprehensive scheduling model for collaborative processing of processing and assembly has been proposed, and good research results have been achieved. Different from the traditional flow-shop and job-shop scheduling problems, comprehensive scheduling is a production activity that allocates limited equipment, personnel and other resources to obtain the best time efficiency and equipment utilization rate. As a scheduling problem that directly affects the production efficiency and social benefits of enterprises, it has always been a hot topic for experts and scholars.

[0004] At present, the research on comprehensive scheduling problems by researchers at home and abroad mainly includes general comprehensive scheduling problems, flexible comprehensive scheduling problems, distributed comprehensive scheduling problems, multi-objective scheduling research and multi-workshop comprehensive scheduling problems. For general comprehensive scheduling, the implemented scheduling algorithms include quasi-critical path method, key equipment compact method, layer priority method, close process group linkage method, reverse order timing method, virtual process method, equipment compact method and event-driven method. However, the layer priority method ignores the advantage that leaf node processes with low layer priority can be scheduled at any time; in the algorithm considering the close connection process group, when the immediate predecessor process is not unique, the connection degree of the vertical serial process will be weakened; the timing algorithm considering the closeness of the serial process is an algorithm mainly based on vertical optimization, which not only ignores the scheduling advantages of leaf node processes at different levels, but also when scheduling vertical serial processes with higher layer priority, many idle time periods will be generated on the corresponding equipment, reducing the equipment utilization rate; the algorithm considering the hierarchical scheduling order overemphasizes the role of horizontal layer priority, weakening the closeness of the vertical decomposition into subtrees for scheduling. Summary of the invention

[0005] The purpose of the present invention is to solve the problem that the prior art ignores the advantage of leaf node processes with low layer priority that can be scheduled at any time in horizontal optimization, and vertically weakens the connection degree of serial processes, thereby generating many idle time periods on the scheduling system equipment, and proposes a comprehensive scheduling method based on the improved Floyd algorithm. The method is to use the structural characteristics of complex products and processing time as optimization factors in the scheduling process of complex products with a tree structure of "cooperation of processing and assembly", and simultaneously achieve the optimization effect of shorter total processing time of complex products and higher overall equipment utilization.

[0006] The present invention is implemented by the following technical scheme. The present invention proposes a comprehensive scheduling method based on an improved Floyd algorithm, and the method comprises the following steps:

[0007] Step 1: According to the improved Floyd algorithm strategy, the processing time of the process itself is used as the path weight of the adjacent process, and the shortest path weight from the root node process of the process tree to the node process with low layer priority is calculated;

[0008] Step 2: Determine whether the node process with the lowest layer priority is unique. If it is unique, establish the shortest path; if it is not unique, select the node with a lower layer priority and less processing time to establish the shortest path;

[0009] Step 3: Pruning, that is, pruning the nodes on the established shortest path from the original process tree, generating several process subtrees, and establishing the shortest path weights from the root node process of several process subtrees to the node process with low layer priority;

[0010] Step 4: Repeat Step 3 until all process path weights are calculated;

[0011] Step 5: Arrange each group of paths in descending order of their weight values;

[0012] Step 6: Establish an initial scheduling plan based on the scheduling advantage strategy;

[0013] Step 7: Adjust the initial scheduling plan based on the constraint relationship review strategy and scheduling advantage strategy;

[0014] Step8: Finish and exit.

[0015] Furthermore, the improved Floyd algorithm strategy is specifically as follows:

[0016] Calculate a point v i =(i=1,2,...,n) to a certain point v r The shortest path of is the root node v i Pass through k nodes to reach the node v with low priorityr The shortest path of Represents node v i The shortest path to itself; accordingly, the path weight value of the improved Floyd algorithm strategy is defined as the reverse order of the path value starting from the process tree node to the leaf node with low layer priority, that is:

[0017]

[0018] At the same time, it is stipulated that when the path values ​​are the same, the path containing more processes will be scheduled first.

[0019] Furthermore, in the improved Floyd algorithm strategy, the original bidirectional weighted directed graph is improved into a unidirectional graph, and the corresponding unidirectional weight matrix is ​​shown in formula (2):

[0020]

[0021] Furthermore, the constraint condition of the scheduling method is: except that the leaf node process has a subsequent process and the root node process has a preceding process, all other node processes have a preceding and following process constraint relationship. After a process is continuously processed, its subsequent process can start processing; the problem model established according to the constraint condition is specifically:

[0022] Resource conditions: p (i+1)m -p im ≥0 (3)

[0023] Constraints: ST (i+1) -ST i ≥t i (4)

[0024] Problem Solving:

[0025]

[0026] Among them, P im is the i-th process being processed on the m-th equipment; ST i is the starting time of the i-th process; T i is the total processing time of the complex product; Formula (3) indicates that the i+1th process can be started after the i-th process is completed on the same equipment m; Formula (4) represents the preceding constraint relationship between processes; Formula (5) represents the problem to be solved so that the total processing time of the complex product T i least.

[0027] Furthermore, suppose there are m processing equipments, and a total of n processes of complex products need to be processed. The specific requirements are as follows:

[0028] (1) Each process has the attributes of process number, corresponding processing equipment number and its own processing time;

[0029] (2) The equipment has time certainty and processing continuity during the processing process;

[0030] (3) Except for the leaf node process, the necessary and sufficient condition for any other process to be processed is that all its immediate predecessor processes or groups have been processed;

[0031] (4) The time it takes to complete the last process on all equipment is the total processing time of the product.

[0032] Furthermore, the layer priority is specifically as follows: assuming that the complex product processing technology tree has n layers, the priority of the root node process is defined as 1, the priority of all descendant node processes of the root node process is defined as 2, and so on, until the priority of all nodes in the nth layer is defined as n; the root node process is defined as the lowest priority, and the process on the nth layer has the highest priority.

[0033] Furthermore, the scheduling advantage strategy is specifically: under the premise of satisfying the process constraint relationship, a certain process has the earliest scheduling time to start scheduling processing on the corresponding equipment.

[0034] Furthermore, the constraint relationship review strategy is specifically as follows: on the basis of the scheduling advantage strategy, based on the hierarchy of the complex product process tree structure, starting from the highest priority layer, in the order of leaf node processes first and non-leaf node processes later, check in turn whether the start processing time of a certain process is greater than or equal to the end time of its predecessor process or group processing; if there are processes with the same layer priority, the leaf node process is scheduled first and then the non-leaf node process; if there are leaf nodes with the same hierarchy or non-leaf nodes with the same hierarchy, the node processes with less processing time are scheduled first.

[0035] The present invention also proposes an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the comprehensive scheduling method based on the improved Floyd algorithm when executing the computer program.

[0036] The present invention also proposes a computer-readable storage medium for storing computer instructions, wherein the computer instructions, when executed by a processor, implement the steps of the comprehensive scheduling method based on the improved Floyd algorithm.

[0037] The beneficial effects of the present invention are:

[0038] (1) The present invention uses the processing time of the next process as the path value of the adjacent previous and next processes, improves the Floyd algorithm, and establishes a process scheduling sequence;

[0039] (2) In terms of vertical optimization, a path weight strategy is designed based on the improved Floyd algorithm, which combines the location advantages of leaf node processes to further improve the effects of horizontal and vertical optimization.

[0040] (3) A scheduling advantage strategy is proposed, where all devices are scheduled from the starting vertex, further improving the utilization of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0042] Figure 1 This is the network structure diagram of the Floyd algorithm;

[0043] Figure 2 To improve the one-way Floyd algorithm structure diagram;

[0044] Figure 3 To improve the one-way tree Floyd algorithm structure diagram;

[0045] Figure 4 Review strategy flow charts for constraint relationships;

[0046] Figure 5 This is a flow chart of the comprehensive scheduling method based on the improved Floyd algorithm of the present invention;

[0047] Figure 6 This is the process tree diagram for complex product A;

[0048] Figure 7 is the path weight graph from the root node to the leaf node process with the lowest layer priority;

[0049] Figure 8 The path weight graph from the subtree root node to the leaf node process with the lowest priority in the subtree layer after the second pruning of complex product A;

[0050] Fig. 9 The path weight graph from the root node of the subtree to the leaf node process with the lowest priority in the subtree layer after the third, fourth, and fifth pruning of complex product A;

[0051] Fig.10 The Gantt chart is initially scheduled for 22 working hours for the present invention;

[0052] Fig.11 Review strategy adjustment process Gantt chart for constraint relationship 27 hours;

[0053] Fig.12 Gantt chart 28 working hours for algorithmic scheduling considering closely connected process groups;

[0054] Fig.13 To schedule Gantt chart 31 working hours by timing algorithm considering the closeness of serial processes;

[0055] Fig.14 Gantt chart 28 working hours are scheduled considering the hierarchical scheduling order algorithm. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] Because the process location characteristics and its own processing time and other attributes in the complex process tree directed graph are crucial to the overall effect of optimizing the comprehensive scheduling of complex products, the present invention uses the process's own processing time as the path weight between processes with constraints. The present invention first establishes a unidirectional path process tree diagram for complex products based on the Floyd algorithm, and uses the processing time of the immediately subsequent process as the path weight between adjacent nodes, that is, the weight value of adjacent nodes on the unidirectional path; then, using the root node of the unidirectional path process tree diagram as the starting point, establish a path from the root node to the leaf node with a lower layer priority. If the leaf node with a lower layer priority is not unique, then the leaf node with a shorter processing time is selected to establish a path. The flow chart of the present invention is as follows: Figure 5 As shown,

[0058] Specific, combined Figure 1-Figure 14 The present invention proposes a comprehensive scheduling method based on an improved Floyd algorithm, the method comprising the following steps:

[0059] Step 1: According to the improved Floyd algorithm strategy, the processing time of the process itself is used as the path weight of the adjacent process, and the shortest path weight from the root node process of the process tree to the node process with low layer priority is calculated;

[0060] Step 2: Determine whether the node process with the lowest layer priority is unique. If it is unique, establish the shortest path; if it is not unique, select the node with a lower layer priority and less processing time to establish the shortest path;

[0061] Step 3: Pruning, that is, pruning the nodes on the established shortest path from the original process tree, generating several process subtrees, and establishing the shortest path weights from the root node process of several process subtrees to the node process with low layer priority;

[0062] Step 4: Repeat Step 3 until all process path weights are calculated;

[0063] Step 5: Arrange each group of paths in descending order of their weight values;

[0064] Step 6: Establish an initial scheduling plan based on the scheduling advantage strategy;

[0065] Step 7: Adjust the initial scheduling plan based on the constraint relationship review strategy and scheduling advantage strategy;

[0066] Step8: Finish and exit.

[0067] The improved Floyd algorithm strategy is specifically as follows:

[0068] Calculate a point v i =(i=1,2,...,n) to a certain point v r The shortest path of is the root node v i Pass through k nodes to reach the node v with low priority r The shortest path of Represents node v i The shortest path to itself; accordingly, the path weight value of the improved Floyd algorithm strategy is defined as the reverse order of the path value starting from the process tree node to the leaf node with low layer priority, that is:

[0069]

[0070] At the same time, it is stipulated that when the path values ​​are the same, the path containing more processes will be scheduled first.

[0071] Floyd algorithm is an algorithm that uses the idea of ​​dynamic programming to find the shortest path between multiple source points in a given weighted graph. It can give the shortest path from a certain starting vertex to other vertices in the network. Floyd algorithm can not only find the shortest path between any two vertices in the network, but also find the shortest path from a certain point to other points and the shortest path between any two vertices. Therefore, it has been widely used in various fields. Let D = (V, E, w) be a weighted directed graph, where V = {v1, v2, ...v n},w ij For arc (v i ,v j ) weight, when v i and v j When there is no arc connecting them, w ij =+∞. Construct the network weight matrix W = (w ij ) n×n ,in:

[0072]

[0073] by Figure 1 Taking the network structure diagram shown in Figure 1 as an example, its weight matrix is ​​shown in formula (1):

[0074]

[0075] In comprehensive scheduling, the process constraints of complex products are represented by a tree structure. Therefore, in the improved Floyd algorithm, the original bidirectional weighted directed graph is improved into a unidirectional graph, such as Figure 2 As shown, the structure diagram after adjusting the tree structure is as follows Figure 3 As shown, the corresponding one-way weight matrix is ​​shown in formula (2):

[0076]

[0077] Assume that there are m processing equipments, and a total of n processes of complex products need to be processed. The specific requirements are as follows:

[0078] (1) Each process has the attributes of process number, corresponding processing equipment number and its own processing time;

[0079] (2) The equipment has time certainty and processing continuity during the processing process;

[0080] (3) Except for the leaf node process, the necessary and sufficient condition for any other process to be processed is that all its immediate predecessor processes or groups have been processed;

[0081] (4) The time it takes to complete the last process on all equipment is the total processing time of the product.

[0082] In order to reduce the overall processing time of complex products, it is necessary to reasonably determine the start processing time of each process. However, in comprehensive scheduling, except for the leaf node process with a subsequent process and the root node process with a preceding process, all other node processes have constraints on the preceding and succeeding processes, and only when the preceding process (group) is completed, can its subsequent constrained process start processing.

[0083] The constraints of the scheduling method are: except for the leaf node process with the next process and the root node process with the previous process, all other node processes have the previous and next process constraints. After a process is continuously processed, its subsequent process can start processing; the problem to be solved is: reasonably schedule each process and determine the start time of each process, so that the overall processing time of complex products is shorter. The problem model established according to the constraint condition is as follows:

[0084] Resource conditions: p (i+1)m -p im ≥0 (3)

[0085] Constraints: ST (i+1) -ST i ≥t i (4)

[0086] Problem Solving:

[0087]

[0088] Among them, P im is the i-th process being processed on the m-th equipment; ST i is the starting time of the i-th process; T i is the total processing time of the complex product; Formula (3) indicates that the i+1th process can be started after the i-th process is completed on the same equipment m; Formula (4) represents the preceding constraint relationship between processes; Formula (5) represents the problem to be solved so that the total processing time of the complex product T i least.

[0089] The layer priority is specifically as follows: assuming that the complex product processing technology tree has n layers, the priority of the root node process is defined as 1, the priority of all descendant node processes of the root node process is defined as 2, and so on, until the priority of all nodes in the nth layer is defined as n; the root node process is defined as having the lowest priority, and the process on the nth layer has the highest priority.

[0090] The scheduling advantage strategy is specifically: under the premise of satisfying the process constraint relationship, a certain process has the earliest scheduling time to start scheduling processing on the corresponding equipment.

[0091] The constraint relationship review strategy is specifically as follows: on the basis of the scheduling advantage strategy, based on the hierarchy of the complex product process tree structure, starting from the highest priority layer, in the order of leaf node processes first and non-leaf node processes later, check in sequence whether the start processing time of a process is greater than or equal to the end time of its predecessor process or group processing; because the leaf node process has no constraints from the predecessor process, the leaf node process can start processing at any relatively early time on the corresponding equipment, thereby prompting its subsequent processes to start processing as early as possible. If there are processes with the same layer priority, the leaf node process is scheduled first and then the non-leaf node process; if there are leaf nodes at the same level or non-leaf nodes at the same level, the node process that takes less processing time will be scheduled first. The algorithm flow chart of the process constraint relationship review strategy is as follows Figure 4 shown.

[0092] Scheduling Example Demonstration

[0093] The present invention is universal and applicable to any complex product with tree-type constraint process requirements. Figure 6The scheduling method of the present invention is demonstrated by taking the complex product A shown as an example.

[0094] Step 1: According to the weights in the improved Floyd algorithm, such as Figure 7 As shown in the red node path, establish a path from the root node to the leaf node process with the lowest layer priority: {A1, A2, A3, A9};

[0095] Step 2: Perform the first pruning based on Step 1 to generate several subtrees. Figure 7 In the middle blue part, the process paths {A4, A5, A6, A10}, {A11, A12, A13, A23, A24, A26} are established from the root nodes of each subtree to the leaf nodes with the lowest priority in the new subtree layer.

[0096] Step 3: Based on Step 2, perform a second pruning to generate several subtrees, such as Figure 8 As shown in the purple part, the process path from the subtree root node to the leaf node with the lowest priority in the new subtree layer is established again: {A7, A8}, {A14, A15, A18}, {A25, A27}.

[0097] Step 4: After the third, fourth, and fifth pruning cycles, the path weight from the subtree root node to the leaf node with the lowest priority in the subtree layer is Fig. 9 The green, orange and black parts are {A16, A19}, {A17, A20, A22}, {A21} respectively. At this time, all process paths have been established.

[0098] Step 5: According to the improved Floyd algorithm strategy, arrange the path weight values ​​of each group in sequence:

[0099] (1){A11, A12, A13, A23, A24, A26},

[0100] (2) {A4, A5, A6, A10},

[0101] (3){A1, A2, A3, A9},

[0102] (4){A14, A15, A18}, {A17, A20, A22}, {A25, A27},

[0103] (5) {A16, A19}, {A21};

[0104] (6){A7, A8}.

[0105] Step 6: According to the scheduling advantage strategy, establish the initial scheduling plan, such as Fig.10 shown.

[0106] Step 7: According to the constraint relationship review strategy and scheduling advantage strategy, adjust the initial scheduling plan, such as Fig.11 As shown, the processing time of complex product A is 27 hours.

[0107] In order to further illustrate the superiority of the present invention, a comparative experimental analysis is conducted between the present invention and a method in the same research field that considers a closely connected process group, a timing method that considers the tightness of serial processes, and a method that considers a hierarchical scheduling order.

[0108] Still taking complex product A as a scheduling example, the processing time of the method considering closely connected working groups is 28 hours, the processing time of the method considering the closeness of serial processes is 31 hours, and the processing time of the method considering the hierarchical scheduling order is 28 hours. The scheduling Gantt chart is as follows: Figure 12-14 shown.

[0109] The overall utilization of the equipment of the above four methods is shown in Table 1. From the perspective of the overall utilization of the equipment in the scheduling system, the method of the present invention is 2.3%, 9.5%, and 0.6% higher than the other three methods, respectively. Therefore, the method of the present invention not only takes less processing time, but also has a higher overall utilization of the equipment, achieving a better scheduling effect.

[0110] Table 1

[0111]

[0112] The main advantages of the present invention are as follows:

[0113] (1) In terms of vertical and horizontal bidirectional optimization, the present invention adopts an improved Floyd algorithm, which takes into account vertical optimization through path value and horizontal optimization through leaf node process strategy. The algorithm considering closely connected process groups and the timing algorithm considering the closeness of serial processes have the problem of emphasizing vertical optimization over horizontal optimization. For example, all equipment in the present invention starts processing at t=0, but on equipment M4, the method considering closely connected work groups, the timing method considering the closeness of serial processes, and the method considering hierarchical scheduling order have 7 working hours, 13 working hours, and 7 working hours of idle time, respectively.

[0114] (2) In terms of equipment utilization, the present invention adopts a scheduling advantage strategy, giving full play to the advantages of leaf node processes without constraints, and effectively reducing the idle time of equipment. The overall utilization of the equipment system of the present invention is increased by 2.3%, 9.5% and 0.6% respectively compared with the method considering closely connected process groups, the timing method considering the closeness of serial processes, and the method considering hierarchical scheduling order.

[0115] For example, on equipment M2, the total idle time of the method of the present invention is 6 working hours, and the total idle time of the equipment by the method considering the closely connected process group method, the timing method considering the closeness of the serial processes, and the method considering the hierarchical scheduling order method are 10 working hours, 12 working hours, and 8 working hours respectively.

[0116] In terms of vertical optimization, the present invention focuses on the impact of the product process tree path length on the scheduling results based on the Floyd algorithm; in terms of horizontal optimization, it focuses on the impact of the same-level processes in the product process tree on parallel scheduling, giving full play to the scheduling advantages of leaf node processes, thereby achieving better scheduling effects in both vertical and horizontal directions. The present invention has advantages that can be used as a reference in subsequent research on multi-product scheduling, flexible product scheduling and distributed scheduling, and has certain theoretical value and practical experience in promoting the development of intelligent manufacturing.

[0117] The present invention also proposes an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the comprehensive scheduling method based on the improved Floyd algorithm when executing the computer program.

[0118] The present invention also proposes a computer-readable storage medium for storing computer instructions, wherein the computer instructions, when executed by a processor, implement the steps of the comprehensive scheduling method based on the improved Floyd algorithm.

[0119] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM). It should be noted that the memory of the method described in the present invention is intended to include, but is not limited to, these and any other suitable types of memory.

[0120] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, a solid state disc (SSD)).

[0121] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software modules in a processor for execution. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0122] It should be noted that the processor in the embodiment of the present application can be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method embodiment can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiment of the present application can be directly embodied as a hardware decoding processor to perform, or the hardware and software modules in the decoding processor can be combined and performed. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0123] The above is a detailed introduction to the comprehensive scheduling method based on the improved Floyd algorithm proposed in the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A comprehensive scheduling method based on the improved Floyd algorithm, characterized in that: The method comprises the following steps: Step 1: According to the improved Floyd algorithm strategy, the processing time of the process itself is used as the path weight of the adjacent process, and the shortest path weight from the root node process of the process tree to the node process with low layer priority is calculated; Step 2: Determine whether the node process with the lowest layer priority is unique. If it is unique, establish the shortest path; if it is not unique, select the node with a lower layer priority and less processing time to establish the shortest path; Step 3: Pruning, that is, pruning the nodes on the established shortest path from the original process tree, generating several process subtrees, and establishing the shortest path weights from the root node process of several process subtrees to the node process with low layer priority; Step 4: Repeat Step 3 until all process path weights are calculated; Step 5: Arrange each group of paths in descending order of their weight values; Step 6: Establish an initial scheduling plan based on the scheduling advantage strategy; Step 7: Adjust the initial scheduling plan based on the constraint relationship review strategy and scheduling advantage strategy; Step8: Finish and exit.

2. The method according to claim 1, characterized in that The improved Floyd algorithm strategy is specifically as follows: Calculate a point v i =(i=1,2,...,n) to a certain point v r The shortest path of is the root node v i Pass through k nodes to reach the node v with low priority r The shortest path of Represents node v i The shortest path to itself; accordingly, the path weight value of the improved Floyd algorithm strategy is defined as the reverse order of the path value starting from the process tree node to the leaf node with low layer priority, that is: At the same time, it is stipulated that when the path values ​​are the same, the path containing more processes will be scheduled first.

3. The method according to claim 2, characterized in that In the improved Floyd algorithm strategy, the original bidirectional weighted directed graph is improved into a unidirectional graph, and the corresponding unidirectional weight matrix is ​​shown in formula (2):

4. The method according to claim 2, characterized in that: The constraint condition of the scheduling method is: except that the leaf node process has a subsequent process and the root node process has a preceding process, all other node processes have a preceding and following process constraint relationship. After a process is continuously processed, its subsequent process can start processing. The problem model established according to the constraint condition is specifically: Resource conditions: p (i+1)m -p im ≥0 (3) Constraints: ST (i+1) -ST i ≥t i (4) Problem Solving: Among them, P im is the i-th process being processed on the m-th equipment; ST i is the starting time of the i-th process; T i is the total processing time of the complex product; Formula (3) indicates that the i+1th process can be started after the i-th process is completed on the same equipment m; Formula (4) represents the preceding constraint relationship between processes; Formula (5) represents the problem to be solved so that the total processing time of the complex product T i least.

5. The method according to claim 1, characterized in that Assume that there are m processing equipments, and a total of n processes of complex products need to be processed. The specific requirements are as follows: (1) Each process has the attributes of process number, corresponding processing equipment number and its own processing time; (2) The equipment has time certainty and processing continuity during the processing process; (3) Except for the leaf node process, the necessary and sufficient condition for any other process to be processed is that all its immediate predecessor processes or groups have been processed; (4) The time it takes to complete the last process on all equipment is the total processing time of the product.

6. The method according to claim 1, characterized in that The layer priority is specifically as follows: assuming that the complex product processing technology tree has n layers, the priority of the root node process is defined as 1, the priority of all descendant node processes of the root node process is defined as 2, and so on, until the priority of all nodes in the nth layer is defined as n; the root node process is defined as having the lowest priority, and the process on the nth layer has the highest priority.

7. The method according to claim 1, characterized in that The scheduling advantage strategy is specifically: under the premise of satisfying the process constraint relationship, a certain process has the earliest scheduling time to start scheduling processing on the corresponding equipment.

8. The method according to claim 1, characterized in that The constraint relationship review strategy is specifically as follows: on the basis of the scheduling advantage strategy, based on the hierarchy of the complex product process tree structure, starting from the highest priority layer, in the order of leaf node processes first and non-leaf node processes later, check in turn whether the start processing time of a certain process is greater than or equal to the end time of its predecessor process or group processing; if there are processes with the same layer priority, the leaf node process is scheduled first and then the non-leaf node process; if there are leaf nodes with the same hierarchy or non-leaf nodes with the same hierarchy, the node processes with less processing time are scheduled first.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium for storing computer instructions, characterized in that: When the computer instructions are executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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