Project progress optimization method for coping with complex time sequence overlap relationship between tasks

Abstract

The invention provides a project progress optimization method for coping with a complex time sequence overlapping relation between tasks. The project progress optimization method comprises the following steps: S10, constructing a complex time sequence overlapping double-code network plan diagram between the tasks in a project; s20, overlapping a double-code network plan graph based on a complex time sequence, and calculating a key path of a project through an improved CPM algorithm; according to the improved CPM algorithm, the calculation starting time, the duration time and the time sequence overlapping relation of each task are utilized to calculate a key path; and S30, solving and finishing project progress optimization through a task construction period shortest optimization method on a critical path, an inter-task complex time sequence overlap relationship optimization method and an optimization method for dynamically adding tasks to meet project construction requirements. According to the method, the key path acquisition algorithm is improved, the acquisition of the key path is simplified and accelerated, the flexibility of the task construction period on the key path, the time redundancy of the immediately preceding task and the independence of the parallel task are fully utilized, and the compilation of the project progress plan is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering project schedule optimization, and in particular to a project schedule optimization method for coping with complex timing overlap relationships between tasks. Background Art

[0002] Traditional project schedule optimization methods mostly consider the constraints of project resources and funds, and focus on theoretical research on issues such as multi-task scheduling, conflict management, and resource allocation. Most methods are based on dynamic resource optimization or project schedule management and optimization under resource-constrained scenarios. This type of optimization algorithm emphasizes the coordination and mutual constraints between resources.

[0003] However, due to the complexity of the project's construction technology and numerous constraints, the management information is complex and intertwined. The traditional project progress optimization method is unable to take into account the various complex timing overlaps between tasks, which easily leads to omissions in scheduling work.

[0004] In addition, the task acquisition method for the project's critical path is complicated and has high calculation costs. It is necessary to calculate the earliest start time, earliest completion time, latest start time, and latest completion time of each task, or it is necessary to repeatedly calculate the duration of multiple task lines. It is difficult to quickly reveal the key tasks that restrict and affect the progress of the entire project, and it is impossible to achieve the expected progress optimization goals, which ultimately leads to project delays and investment failures.

[0005] At the same time, the traditional method assumes that tasks that appear in the scheduling plan will not be added dynamically, which makes it difficult to meet the needs of project planning with new tasks and lacks progress optimization and control of new tasks. Summary of the invention

[0006] The technical problem to be solved by the present invention is how to efficiently and reliably optimize the project schedule, and to provide a project schedule optimization method that copes with the complex timing overlap relationship between tasks.

[0007] A project schedule optimization method for coping with complex timing overlap relationships between tasks according to an embodiment of the present invention includes:

[0008] S10, construct a complex time-sequence double-code network planning diagram between tasks in the project;

[0009] S20, based on the complex time-sequence overlapped dual-code network planning diagram, calculating the critical path of the project by using an improved CPM algorithm; wherein the improved CPM algorithm calculates the critical path by using the calculation start time, duration and time-sequence overlap relationship of each task;

[0010] S30, through the optimization method of shortest duration of tasks on the critical path, the optimization method of complex timing overlap between tasks and the optimization method of dynamically adding tasks to meet the requirements of project construction, the project schedule optimization is completed.

[0011] According to some embodiments of the present invention, in step S20, the method for calculating the critical path specifically includes:

[0012] S21, based on the complex time sequence overlap double code network planning diagram, calculate the calculation start time and calculation completion time of each task;

[0013] S22, according to the complex time sequence double-code network planning diagram, search from left to right for the first task with the earliest calculated start time and the longest task duration, as the first task of the critical path;

[0014] S23, when the first task of the critical path is completed, check whether there is a task started and not completed during the execution of the first task. If there is, the task with the longest duration that has started and not completed is selected as the next task of the critical path; if there is no task, select the next task with the latest calculation start time and the longest task duration as the next task of the critical path; until the last task with the latest calculation completion time is found, which is the last task on the critical path.

[0015] In some embodiments of the present invention, in step S30, the method for optimizing the shortest duration of tasks on the critical path includes:

[0016] S311, traverse each task on the critical path to determine whether the task duration is flexible. If so, optimize the project schedule by compressing the task duration.

[0017] S312, if the task duration is not flexible, determine whether there is time redundancy between the task and the immediate predecessor task; if there is redundancy, optimize the project schedule by compressing the time redundancy between the task and the immediate predecessor task;

[0018] S313, determining whether the task and the task on the critical path are parallel tasks, and if so, optimizing the project schedule by advancing the task duration.

[0019] According to some embodiments of the present invention, in step S30, the method for optimizing the complex timing overlap relationship between tasks includes:

[0020] Traverse the tasks in the project that have timing overlap relationships, determine the types of timing overlap relationships, and determine whether the planned times of tasks of different overlap types meet the requirements of the corresponding timing overlap relationships, and give corresponding optimization suggestions for tasks that do not meet the requirements of the corresponding timing overlap relationships.

[0021] In some embodiments of the present invention, when there are new tasks, in step S30, the optimization method for dynamically adding new tasks to meet the project construction requirements includes:

[0022] S321, traverse the newly added tasks of the project and determine whether the newly added tasks are tasks on the critical path;

[0023] S322, if the newly added task is a task on the critical path, the project schedule is optimized according to the shortest duration optimization method for tasks on the critical path;

[0024] S323, determining whether there is a time sequence overlap relationship between the newly added tasks, and if so, optimizing the project schedule according to an optimization method for complex time sequence overlap relationships between tasks;

[0025] S324, determining whether the planned completion time of the newly added task is within the project construction cycle, if not, optimizing and adjusting the planned completion time of the newly added task to be within the project construction cycle.

[0026] According to some embodiments of the present invention, in step S321, determining whether the newly added task is a task on the critical path specifically includes:

[0027] Calculate the calculation start time and calculation completion time of the new task according to the timing overlap relationship of the newly added tasks;

[0028] Compare and sort the calculation start time of the newly added tasks with the calculation start time of the tasks on the critical path;

[0029] Select the task on the critical path that is closest to the calculation start time of the newly added task, and start calculating from this task according to the improved critical path calculation method to determine whether the calculation start time, calculation completion time and duration of the new task meet the requirements for critical path task selection. If so, add it to the critical path, otherwise do not add it.

[0030] In some embodiments of the present invention, step S30 further includes: summarizing and providing all project schedule optimization suggestions.

[0031] The present invention has the following beneficial effects:

[0032] The present invention improves the critical path acquisition algorithm based on the critical path generation mechanism of the network planning method. It does not need to calculate the earliest start time, earliest completion time, latest start time, and latest completion time of each task, nor does it need to repeatedly calculate the duration of multiple task lines. It simplifies and accelerates the acquisition of the critical path, fully utilizes the flexibility of the task duration on the critical path, the time redundancy with the preceding task, and the independence of parallel tasks, and optimizes the preparation of the project schedule.

[0033] The present invention introduces the influence of complex timing overlap relationships between tasks, establishes a corresponding optimization model, and optimizes the schedule with project timing overlap relationships through an optimization method of complex timing overlap relationships between tasks.

[0034] The present invention designs an optimization method for dynamically adding tasks to meet project construction requirements, speeds up the judgment process of whether a newly added task is a key task, and solves the need for dynamically adding tasks during project construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a general flow chart of a project schedule optimization method for dealing with complex timing overlap relationships between tasks according to an embodiment of the present invention;

[0036] Figure 2 A diagram illustrating a complex timing overlap relationship according to an embodiment of the present invention;

[0037] Figure 3 A calculation flow chart of a project critical path according to an embodiment of the present invention;

[0038] Figure 4 A schematic diagram of a method for prioritizing optimization of tasks on a critical path according to an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of a method for optimizing a complex timing overlap relationship between tasks according to an embodiment of the present invention;

[0040] Figure 6 A schematic diagram of an optimization method for dynamically adding tasks to meet project construction requirements according to an embodiment of the present invention;

[0041] Figure 7 A network planning diagram for building a certain software and hardware platform according to an embodiment of the present invention;

[0042] Figure 8 A key path diagram according to an embodiment of the present invention;

[0043] Fig. 9 This is a critical path diagram after adding tasks according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose, the present invention is described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0045] The description of the method flow in the specification of the present invention and the steps of the flow chart in the drawings of the specification of the present invention do not have to be strictly executed according to the step numbers, and the method steps can be executed in a different order. Moreover, some steps can be omitted, multiple steps can be combined into one step, and / or one step can be decomposed into multiple steps.

[0046] The present invention constructs a complex time-sequence overlapping double-code network planning diagram between tasks in a project, sorts the tasks in the project according to the progress and the time-sequence relationship between the tasks, marks the time-sequence relationship of the tasks, calculates the critical path of the project by using the calculated start time, duration and time-sequence overlapping relationship of each task through an improved CPM (Critical Path Method) method, and simultaneously calculates the progress redundancy between tasks on the critical path. Based on this, a schedule optimization model for the project is established, and the optimization method for the shortest duration of tasks on the critical path, the optimization method for the complex time-sequence overlapping relationship between tasks and the optimization method for dynamically adding tasks to meet the requirements of project construction are used to solve the optimization of the project schedule in response to the complex time-sequence overlapping relationship between tasks.

[0047] Among them, in view of the fact that traditional project schedule optimization methods are difficult to quickly reveal the key tasks that restrict and affect the progress of the entire project, the present invention improves the key path acquisition algorithm based on the key path generation mechanism of the network planning method, simplifies and accelerates the acquisition of the key path, and makes full use of the flexibility of the task duration on the critical path, the time redundancy with the preceding task and the independence of parallel tasks, so as to optimize the preparation of the project schedule.

[0048] In view of the shortcoming that traditional project schedule optimization methods cannot take into account various complex timing overlap relationships between tasks, the present invention introduces the impact of complex timing overlap relationships between tasks, establishes a corresponding optimization model, and optimizes the preparation of project schedule plans.

[0049] In view of the fact that traditional progress optimization methods are difficult to meet the needs of project planning with newly added tasks, the present invention designs a method for quickly determining whether a newly added task is a critical path task, thereby solving the optimization needs of dynamically added tasks during project construction.

[0050] Compared with the traditional project schedule optimization method, the present invention has the following advantages:

[0051] First, the preparation of the project schedule will timely introduce the influence of the complex timing overlap relationship between tasks, and timely consider the impact of the new tasks on the project schedule design, and at the same time, utilize the progress redundancy between tasks on the critical path and the parallel tasks on the non-critical path; second, the application of the method of the present invention will make the solution of the critical path more efficient, and there is no need to calculate the earliest start time, earliest completion time, latest start time, and latest completion time of each task, nor is there any need to repeatedly calculate the duration of multiple task lines. It can be completed based on the calculated start time of the task and the duration of the task. It has the characteristics of low computing intensity and strong adaptability, can timely discover the constraints that affect the project schedule optimization process, and can identify and analyze them, greatly improving the efficiency of project schedule optimization.

[0052] The overall flow chart of the present invention is as follows Figure 1 shown.

[0053] (I) Construction of a complex time-sequence double-code network planning diagram:

[0054] The double-code network planning diagram drawing principle is adopted to directly draw and construct the timing overlap network diagram between tasks in the project.

[0055] (II) Calculation of project critical path:

[0056] Since the present invention builds a complex timing overlap relationship between tasks, the calculation of the critical path of the project will adapt to this relationship on the basis of the improved critical path method. The timing overlap relationship is as follows: Figure 2 As shown, the application process includes the following 7 steps: Figure 3 As shown:

[0057] (1) Calculate the calculation start time (S) of each task based on the project's timing overlap network plan. The start time S of task j is j It depends on the calculated start time of its immediate predecessor task i (one or more tasks) and the overlap relationship between them and the task duration (D j ), the calculation method is as follows:

[0058]

[0059] (2) The computation completion time of task j depends on the computation start time and task duration (D j ) is calculated as follows:

[0060] F j =S j +D j ;

[0061] (3) According to the network planning diagram, search from left to right for the first task i (with the shortest start time S) that starts the earliest and has the longest duration. This task is the first task on the critical path.

[0062] (4) When this task is completed, check whether there are any tasks that started and have not been completed during the execution of this task (S j <F i And F j >F i ), if it exists, the task with the longest duration that has been started and not yet completed is selected as the task of the next critical path; if it does not exist, the next task with the closest calculation start time (min(|S j –S i |)) and the task with the longest task duration (max(D j )) is the next key task.

[0063] (5) Calculate the time redundancy between the next task and the previous task. The calculation method is as follows:

[0064] ΔT j =S j计划 -S j计算 ;

[0065] (6) Repeat steps 4-5 until the task with the latest calculated completion time is found, which is the last critical task on the critical path.

[0066] (7) After completing the search for the critical path, the final time consumption of the project is obtained based on the calculation time of the task.

[0067] ΔT 总 =T maxF -T minS .

[0068] (III) Establishment and solution of project schedule optimization model:

[0069] The variable description of the optimization model of the present invention is shown in Table 1.

[0070] Table 1 Optimization model variables illustration

[0071] Variable Name Variable Description i The number of the predecessor task j The number of the next task <![CDATA[ΔT 总 ]]> The total duration of tasks on the critical path <![CDATA[T maxF ]]> The latest finish time of tasks on the critical path <![CDATA[T minS ]]> The earliest start time for tasks on the critical path <![CDATA[T newF ]]> Added task completion time F Completion time of the task S The start time of the task <![CDATA[T 计 ]]> Total project duration

[0072] 1. The optimization method to minimize the duration of tasks on the critical path.

[0073] The task optimization method on the critical path includes the following steps: Figure 4 shown.

[0074] (1) Traverse each task on the critical path and determine whether the task duration has a certain degree of flexibility. If so, the optimization effect can be achieved by compressing the task duration and providing progress optimization suggestions.

[0075] (2) If the task duration is not flexible, determine whether there is time redundancy between the task and the immediate predecessor task. If there is redundancy, the optimization effect can be achieved by compressing the time redundancy with the immediate predecessor task, and make progress optimization suggestions.

[0076] (3) Determine whether the task is a parallel task (a task that has no time overlap). If it is a parallel task, the project efficiency can be improved by advancing the task duration and providing progress optimization suggestions.

[0077] (4) Continue to repeat (1) to (3) to optimize the next task until all tasks on the critical path have been traversed.

[0078] (5) Finally, summarize all the project schedule optimization suggestions for tasks on the critical path with the shortest duration.

[0079] 2. Optimization method for complex timing overlap between tasks.

[0080] The optimization method for complex timing overlap between tasks includes the following steps: Figure 5 shown.

[0081] (1) Traverse the tasks in the project that have timing overlap relationships and determine the type of timing overlap relationship. If it is an FTS overlap relationship, perform step 2; if it is an STS overlap relationship, perform step 3; if it is an FTF overlap relationship, perform step 4; and if it is an STF overlap relationship, perform step 5.

[0082] (2) If the overlap relationship is FTS, determine whether the task planning time meets FTS. i ≤S j , does not meet the requirements, then the overlap relationship gives optimization suggestions.

[0083] (3) If the overlap relationship is STS, determine whether the task planning time meets STS. i ≤S j , does not meet the requirements, then the overlap relationship gives optimization suggestions.

[0084] (4) If the overlap relationship is FTF, determine whether the task planning time meets FTF. i ≤F j , does not meet the requirements, then the overlap relationship gives optimization suggestions.

[0085] (5) If the overlap relationship is STF, determine whether the task planning time meets S j ≤F i, does not meet the requirements, then the overlap relationship gives optimization suggestions.

[0086] (6) Continue to repeat steps 1 to 5 to optimize the next task with a timing overlap relationship until all tasks with a timing overlap relationship have been traversed.

[0087] (7) Finally, summarize all project schedule optimization suggestions based on timing overlap.

[0088] 3. Optimization method to dynamically add tasks to meet project construction requirements.

[0089] During the project construction process, the optimization method of dynamically adding tasks to meet the project construction requirements includes the following steps: Figure 6 shown.

[0090] (1) Traverse the newly added tasks of the project and determine whether the task is on the critical path.

[0091] (2) When making a judgment, first calculate the calculation start time of the new task based on the timing overlap relationship of the newly added tasks.

[0092] (3) Compare and sort the calculation start time of the newly added task with the calculation start time of the tasks on the critical path, and then select the task on the critical path that is closest to the start time of the newly added task (min(|S new -S i |)), starting from this task, the calculation is performed according to the improved critical path calculation method of the present invention to determine whether the calculation start time and duration of the new task meet the requirements for the critical path task selection. If the requirements are met, it is added to the critical path, otherwise it is not added.

[0093] (4) If the new task is a critical path task, optimize it according to step 5; determine whether the task has a timing overlap relationship, if so, optimize it according to step 6; determine whether the planned completion time of the task is within the project construction cycle, if not, optimize it according to step 7;

[0094] (5) If the task is on the critical path, it is optimized using the shortest duration optimization method for tasks on the critical path.

[0095] (6) If there is a timing overlap between the tasks, the optimization is performed according to the optimization method for complex timing overlap between tasks.

[0096] (7) Determine the scope of the project construction period. If the planned completion time of the task is not within the scope of the project construction period (T newF >T 计 ), optimize and adjust the planned completion time of new tasks within the project construction cycle.

[0097] (8) Continue to repeat 4 to 7 to optimize the next newly added task until all newly added tasks have been traversed.

[0098] (9) Finally, summarize all project schedule optimization suggestions that dynamically add tasks to meet project construction requirements.

[0099] The following takes the construction of a certain software and hardware platform of a navigation satellite as an example, and describes the present invention in detail in combination with the accompanying drawings. A certain software and hardware platform construction project is decomposed into 8 work tasks, and the construction period is 150 days. See Table 2.

[0100] Table 2 Task breakdown table

[0101]

[0102] (I) The eight tasks and the timing connection between them are drawn and constructed using the principle of drawing a double-code network plan diagram. Figure 7 shown.

[0103] (2) Use the improved critical path method to calculate the critical path of this project.

[0104] Calculate the calculation start time (S) of each task:

[0105] Task 1: S1 = 0;

[0106] Task 2: S2 = 5;

[0107] Task 3: S3=30;

[0108] Task 4: S4=85;

[0109] Task 5: S5 = 95;

[0110] Task 6: S6 = 95;

[0111] Task 7: S7=95;

[0112] Task 8: S8=125;

[0113] Calculate the computational completion time (F) for each task:

[0114] Task 1: F1 = 10;

[0115] Task 2: F2 = 25;

[0116] Task 3: F3 = 90;

[0117] Task 4: F4 = 95;

[0118] Task 5: F5 = 125;

[0119] Task 6: F6 = 115;

[0120] Task 7: F7 = 105;

[0121] Task 8: F8 = 145;

[0122] According to the network planning diagram, search from left to right for the first task with the earliest calculated start time and the longest task duration. Task 1 is the first task on the critical path.

[0123] When Task 1 is completed, the query shows that Task 2 started and did not end during the execution of Task 1. Task 2 is the second task in the critical path. If we search in this way, the critical path is Task 1-2-3-4-5-8. Figure 8 shown.

[0124] The time redundancy between each task and its predecessor task:

[0125] Task 1: ΔT1=0-0=0;

[0126] Task 2: ΔT2 = 9-5 = 4;

[0127] Task 3: ΔT3 = 30-30 = 0;

[0128] Task 4: ΔT4=85-85=0;

[0129] Task 5: ΔT5 = 95-95 = 0;

[0130] Task 6: ΔT6=95-95=0;

[0131] Task 7: ΔT7=95-95=0;

[0132] Task 8: ΔT8 = 120-125 = -5;

[0133] Get the final time-consuming result of the project based on the calculation time of the task:

[0134] ΔT 总 =145-0=145.

[0135] (III) Establishment and solution of project schedule optimization model.

[0136] The optimization method to minimize the duration of tasks on the critical path:

[0137] (1) Traverse each task on the critical path. Task 1 has a certain degree of flexibility, so it is recommended to shorten the task time.

[0138] (2) The time redundancy of Task 2 is ΔT2 = 9-5 = 4. It is recommended that the planned start time of Task 2 be advanced by 4 days. The time redundancy of Tasks 1, 3, 4, 5, 6, and 7 is 0, and the time redundancy of Task 8 is -5, which does not need to be optimized.

[0139] (3) Tasks 6 and 7 are parallel tasks of Task 5. It is recommended that they be executed as soon as possible.

[0140] (4) Summary of optimization suggestions for the shortest duration of tasks on the critical path: It is recommended to shorten the task time for Task 1; it is recommended to advance the planned start time of Task 2 by 4 days; it is recommended to execute Tasks 6 and 7 as soon as possible.

[0141] Optimization method for complex timing overlap between tasks:

[0142] (1) Traverse the tasks in the project that have temporal overlap relationships.

[0143] (2) Task 4 is in FTS overlap relationship with tasks 5, 6, and 7, and the task planning time satisfies F4 ≤ S 5、6、7 Required, no optimization required.

[0144] (3) Task 2 and Task 3 are in an FTS overlap relationship, and the task planning time meets the requirement of F2≤S3, so no optimization is required.

[0145] (4) Tasks 5, 6, 7 and Task 8 are in an FTS overlap relationship. The planned start time of Task 8 is less than the end time of Task 5. The start time of Task 8 needs to be optimized and adjusted.

[0146] (5) Task 1 and Task 2 are in an STS overlap relationship, and the task planning time satisfies S1≤S2, so no optimization is required.

[0147] (6) There is no FTF overlap in the project tasks and no optimization is required.

[0148] (7) Task 4 and Task 3 are in an STF overlap relationship, and the task planning time satisfies S4≤F3, which meets the requirements and does not need to be optimized.

[0149] (8) Summary of optimization suggestions for complex timing overlaps between tasks: The planned start time of Task 8 needs to be optimized.

[0150] (IV) Optimization method for dynamically adding tasks to meet project construction requirements.

[0151] During the construction of the software and hardware platform, a new task of "computer room renovation" was temporarily added. The detailed information is shown in Table 3. The new task has an FTF overlap relationship with the previous task. new =10.

[0152] Table 3 Newly added tasks

[0153]

[0154] (1) Calculate the start time of the new task (S): S new=F5+LT new -D new =125+10-20=115;

[0155] (2) Calculate the completion time of the newly added task (F): F new =S new +D new =115+20=135;

[0156] (3) Time redundancy between new tasks and predecessor tasks:

[0157] Task new: ΔT new =115-125=-10;

[0158] (4) Compare and sort the calculation start time of the newly added task with the calculation start time of the tasks on the critical path. If the calculation start time and duration of the new task meet the requirements for selecting the critical path task, then the newly added task is a critical path task. Fig. 9 shown.

[0159] (5) The redundancy of the newly added task is -10, and no optimization is required.

[0160] (6) The newly added tasks have an FTF overlap relationship, and the planned completion time 110<125. There is a conflict in the overlap relationship, so the planned start time needs to be optimized and adjusted.

[0161] (7) The planned construction time range of the newly added tasks is 90-110, which is within the range of the project construction cycle (0-150) and does not require optimization.

[0162] (8) Summary of optimization suggestions for dynamically adding tasks to meet project construction requirements: The planned start time of new tasks needs to be optimized and adjusted.

[0163] In summary, the present invention improves the critical path acquisition algorithm based on the critical path generation mechanism of the network planning method. It does not need to calculate the earliest start time, earliest completion time, latest start time, and latest completion time of each task, nor does it need to repeatedly calculate the duration of multiple task lines. It simplifies and accelerates the acquisition of the critical path, fully utilizes the flexibility of the task duration on the critical path, the time redundancy with the preceding task, and the independence of parallel tasks, and optimizes the preparation of the project schedule.

[0164] The present invention introduces the influence of complex timing overlap relationships between tasks, establishes a corresponding optimization model, and optimizes the schedule with project timing overlap relationships through an optimization method of complex timing overlap relationships between tasks.

[0165] The present invention designs an optimization method for dynamically adding tasks to meet project construction requirements, speeds up the judgment process of whether a newly added task is a key task, and solves the need for dynamically adding tasks during project construction.

[0166] Through the description of the specific implementation methods, a deeper and more specific understanding of the technical means and effects adopted by the present invention to achieve the predetermined purpose should be obtained. However, the accompanying drawings are only for reference and illustration purposes and are not intended to limit the present invention.

Claims

1. A project schedule optimization method for dealing with complex timing overlap relationships between tasks, characterized in that: include: S10, construct a complex time-sequence double-code network planning diagram between tasks in the project; S20, based on the complex time-sequence overlapped dual-code network planning diagram, calculating the critical path of the project by using an improved CPM algorithm; wherein the improved CPM algorithm calculates the critical path by using the calculation start time, duration and time-sequence overlap relationship of each task; S30, optimizes the project schedule by optimizing the shortest duration of tasks on the critical path, optimizing the complex timing overlap relationship between tasks, and optimizing the dynamic addition of tasks to meet project construction requirements.

2. The project schedule optimization method for coping with complex timing overlap relationships between tasks according to claim 1 is characterized in that: In step S20, the critical path calculation method specifically includes: S21, based on the complex time sequence overlap double code network planning diagram, calculate the calculation start time and calculation completion time of each task; S22, according to the complex time sequence double-code network planning diagram, search from left to right for the first task with the earliest calculated start time and the longest task duration, as the first task of the critical path; S23, when the first task of the critical path is completed, check whether there is a task started and not completed during the execution of the first task. If there is, the task with the longest duration that has started and not completed is selected as the next task of the critical path; if there is no task, select the next task with the latest calculation start time and the longest task duration as the next task of the critical path; until the last task with the latest calculation completion time is found, which is the last task on the critical path.

3. The project schedule optimization method for dealing with complex time-sequence overlap relationships between tasks according to claim 1 is characterized in that: In step S30, the method for optimizing the shortest duration of tasks on the critical path includes: S311, traverse each task on the critical path to determine whether the task duration is flexible. If so, optimize the project schedule by compressing the task duration. S312, if the task duration is not flexible, determine whether there is time redundancy between the task and the immediate predecessor task; if there is redundancy, optimize the project schedule by compressing the time redundancy between the task and the immediate predecessor task; S313, determining whether the task and the task on the critical path are parallel tasks, and if so, optimizing the project schedule by advancing the task duration.

4. The project schedule optimization method for coping with complex time sequence overlap relationships between tasks according to claim 1 is characterized in that: In step S30, the optimization method of the complex timing overlap relationship between tasks includes: Traverse the tasks in the project that have timing overlap relationships, determine the types of timing overlap relationships, and determine whether the planned times of tasks of different overlap types meet the requirements of the corresponding timing overlap relationships, and give corresponding optimization suggestions for tasks that do not meet the requirements of the corresponding timing overlap relationships.

5. The project schedule optimization method for coping with complex time sequence overlap relationships between tasks according to claim 1 is characterized in that: When there are new tasks, in step S30, the optimization method for dynamically adding new tasks to meet the project construction requirements includes: S321, traverse the newly added tasks of the project and determine whether the newly added tasks are tasks on the critical path; S322, if the newly added task is a task on the critical path, the project schedule is optimized according to the shortest duration optimization method for tasks on the critical path; S323, determining whether there is a time sequence overlap relationship between the newly added tasks, and if so, optimizing the project schedule according to an optimization method for complex time sequence overlap relationships between tasks; S324, determining whether the planned completion time of the newly added task is within the project construction cycle, if not, optimizing and adjusting the planned completion time of the newly added task to be within the project construction cycle.

6. The project schedule optimization method for coping with complex time-sequence overlap relationships between tasks according to claim 5 is characterized in that: In step S321, determining whether the newly added task is a task on the critical path specifically includes: Calculate the calculation start time and calculation completion time of the new task according to the timing overlap relationship of the newly added tasks; Compare and sort the calculation start time of the newly added tasks with the calculation start time of the tasks on the critical path; Select the task on the critical path that is closest to the calculation start time of the newly added task, and start calculating from this task according to the improved critical path calculation method to determine whether the calculation start time, calculation completion time and duration of the new task meet the requirements for critical path task selection. If so, add it to the critical path, otherwise do not add it.

7. The project schedule optimization method for coping with complex time sequence overlap relationships between tasks according to claim 1 is characterized in that: Step S30 also includes: summarizing and providing all project progress optimization suggestions.

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