Event tree success branch quantification methods, systems, media, and devices

Abstract

This invention relates to a method, system, medium, and device for quantifying successful branches in an event tree, comprising: calculating the minimum cut set of failed branches of a function header and the probability value of the failed branch; calculating the probability of a successful branch based on the probability value of the failed branch; calculating the minimum cut set of a sequence; reducing the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set; calculating the frequency of the sequence according to the new minimum cut set; and correcting the frequency of the sequence using the probability of the successful branch to obtain the target frequency of the sequence. This invention addresses the correlation between the minimum cut set of the sequence and the minimum cut set of the failed function header corresponding to the successful branch by removing the minimum cut set of the failed function header corresponding to the successful branch from the minimum cut set of the sequence, thus ensuring the accuracy of the minimum cut set of the sequence. Simultaneously, it corrects the frequency of the sequence by using the frequency of the sequence, ensuring the accuracy and reliability of the frequency and avoiding frequency overestimation.

Description

Technical Field

[0001] This invention relates to the technical field of probabilistic security analysis, and more specifically, to a method, system, medium, and device for quantifying successful branching in an event tree. Background Technology

[0002] With the development of the nuclear power industry, probabilistic analysis has deepened, expanding from single-level probabilistic safety analysis of internal events to full-range probabilistic safety analysis. Currently, there is a consensus within the industry regarding the requirements and methods for constructing probabilistic safety analysis models. Extensive foundational work has been done in reliability data collection and processing, and related research has also been conducted on quantitative methods. The quantification of probabilistic safety analysis mainly requires addressing the quantification of fault trees and event trees, with the quantification of event trees primarily focusing on the quantification of successful branches.

[0003] For the Level 1 Probabilistic Safety Analysis (PSA) model of internal events, since its basic events are mainly composed of low-probability events, the successful branches of the event tree can be conservatively calculated using simplified methods. These methods include directly assuming the probability of a successful branch to be 1 and directly subtracting the failure probability from 1 to conduct quantitative analysis of the event tree. These two simplified and conservative methods have little impact on the quantitative results for Level 1 PSA of internal events. However, for Level 2 PSA or earthquake PSA, which have many basic event models with a high probability of failure, the quantitative results will be greatly overestimated, affecting the accuracy of the probabilistic safety assessment results and the true risk identification.

[0004] Specifically, the first approach sets the probability of a successful branch for each question in the event tree to 1, disregarding the logical relationship between the input of that question and other questions. This leads to an overestimation of the probability of the event sequence occurring (up to 135%). The second approach sets the probability of a successful branch for each question in the event tree to 1 minus the probability of a failed branch, also disregarding the logical relationship between the input of that question and other questions. During quantification, the probability of a successful branch is multiplied by the frequency of the sequence obtained without considering the successful branch to correct the sequence frequency. Using this method, the probability of the event sequence occurring is also overestimated (up to 90%). Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method, system, medium and device for quantifying successful branching of an event tree, addressing the problems existing in the prior art.

[0006] The technical solution adopted by this invention to solve its technical problem is: constructing a method for quantifying successful branching in an event tree, comprising the following steps: Step S10: Obtain the function header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failed branch of the function header and the probability value of the failed branch; Step S20: Calculate the probability of the successful branch based on the probability value of the failed branch; Step S30: Convert the sequence containing the successful branch into a fault tree and calculate the minimum cut set of the sequence; Step S40: Reduce the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set; Step S50: Calculate the frequency of the sequence based on the new minimum cut set; Step S60: Correct the frequency of the sequence based on the probability of the successful branch to obtain the target frequency of the sequence.

[0007] In the event tree successful branch quantification method described in this invention, step S10, calculating the minimum cut set of the failed branch of the functional header and the probability value of the failed branch, includes: Determine the input type of the function header; The minimum cut set and probability value of the failed branch are obtained by calculating based on the input type of the function header.

[0008] In the event tree successful branch quantification method described in this invention, the input types of the function header include: basic events; If the input type of the function header is a basic event, then the minimum cut set and probability value of the failed branch are calculated in the following way: Use the basic events as the minimum cut set of the failed branches; The value of the basic event is used as the probability value of the failed branch.

[0009] In the event tree successful branch quantification method described in this invention, the input type of the function header includes: fault tree; If the input type of the function header is a fault tree, then the minimum cut set and probability value of the failed branch are calculated in the following way: The minimum cut set and probability value of the failed branch are calculated using the fault tree solution method.

[0010] In the event tree successful branch quantification method described in this invention, the fault tree solving method includes any one of the following: the upward method, the downward method, and the binary decision graph method.

[0011] In the event tree successful branch quantification method of the present invention, step S20, calculating the probability of the successful branch based on the probability value of the failed branch, includes: The difference is obtained by subtracting the probability value of the failed branch from the set value; The difference is determined as the probability of the successful branch.

[0012] In the event tree successful branch quantification method of the present invention, step S30, which converts the sequence containing successful branches into a fault tree and calculates the minimum cut set of the sequence, includes: For successful branches in the sequence, ignore their function headers; The sequence is converted into a fault tree; The fault tree is associated with the sequence. After the setup is complete, the minimum cut set of the fault tree is calculated; the minimum cut set of the fault tree is the minimum cut set of the sequence.

[0013] In the event tree successful branch quantification method of the present invention, the step of associating the fault tree with the sequence includes: The top event of the fault tree is identified as the consequence of the sequence; An AND gate is set under the top event, and the input of the AND gate is the input of the initiating event and the corresponding function header failure.

[0014] In the event tree successful branch quantification method of the present invention, step S40, which involves reducing the minimum cut set of the sequence based on the minimum cut set of the failed branch to obtain a new minimum cut set, includes: Traverse the minimum cut set of the sequence based on the minimum cut set of the failed branches; If the minimum cut set of the sequence contains any minimum cut set in the minimum cut set of the failed branch, then the corresponding minimum cut set in the minimum cut set of the sequence is used to obtain the new minimum cut set.

[0015] In the event tree successful branch quantification method described in this invention, in step S50, the frequency of the sequence is calculated using a first-order approximation algorithm, a limit approximation algorithm, or a binary decision graph algorithm.

[0016] In the event tree successful branch quantification method of the present invention, step S60, correcting the frequency of the sequence by the probability of the successful branch to obtain the target frequency of the sequence includes: The target frequency of the sequence is obtained by multiplying the probability of the successful branch by the frequency of the sequence.

[0017] The present invention also provides a system for quantifying successful branching in an event tree, comprising: The failure branch probability calculation unit is used to obtain the functional header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failure branch of the functional header and the probability value of the failure branch. A successful branch probability calculation unit is used to calculate the probability of the successful branch based on the probability value of the failed branch; The sequence transformation unit is used to transform a sequence containing a successful branch into a fault tree and to compute the minimum cut set of the sequence. The minimum cut set processing unit is used to reduce the minimum cut set of the sequence based on the minimum cut set of the failed branch to obtain a new minimum cut set; A sequence frequency calculation unit is used to calculate the frequency of the sequence based on the new minimum cut set; A frequency correction unit is used to correct the frequency of the sequence based on the probability of the successful branch, thereby obtaining the target frequency of the sequence.

[0018] The present invention also provides a storage medium storing a computer program adapted for loading by a processor to execute the steps of the event tree successful branch quantification method as described above.

[0019] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the steps of the event tree success branch quantification method as described above by calling the computer program stored in the memory.

[0020] The method, system, medium, and device for quantifying successful branches in event trees according to the present invention have the following beneficial effects: They include: calculating the minimum cut set of failed branches of a function header and the probability value of the failed branch; calculating the probability of a successful branch based on the probability value of the failed branch; calculating the minimum cut set of the sequence; reducing the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set; calculating the frequency of the sequence according to the new minimum cut set; and correcting the frequency of the sequence by the probability of the successful branch to obtain the target frequency of the sequence. The present invention addresses the correlation between the minimum cut set of the sequence and the minimum cut set of the failed function header corresponding to the successful branch by removing the minimum cut set of the failed function header corresponding to the successful branch from the minimum cut set of the sequence, ensuring the accuracy of the minimum cut set of the sequence. Simultaneously, by correcting the frequency of the sequence, it ensures the accuracy and reliability of the sequence frequency and avoids frequency overestimation. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a flowchart illustrating the method for quantifying successful branching in an event tree provided by the present invention. Figure 2 This is an example diagram of the event tree provided by the present invention; Figure 3 This is the fault tree corresponding to the failure of the functional header provided by this invention; Figure 4 This is the present invention. Figure 2 In the event tree, sequence 2 does not consider the transformation of successful branch effects into a fault tree; Figure 5 This is a logic block diagram of the event tree successful branch quantification system provided by the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To address the problem of overestimating the probability of event sequences in existing technologies, this invention provides a method for quantifying successful branches in an event tree. This method addresses the correlation between the minimum cut set of a sequence and the minimum cut set of failed functional headers corresponding to successful branches by deleting the minimum cut set containing the minimum cut set of the sequence's minimum cut set. Furthermore, by multiplying the probability of a successful branch by the frequency of the sequence, the frequency of the sequence is corrected, ensuring that the final frequency of the sequence is not overestimated.

[0024] refer to Figure 1 In a preferred embodiment, the event tree successful branch quantification method includes the following steps: Step S10: Obtain the function header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failed branch of the function header and the probability value of the failed branch.

[0025] Specifically, a successful branch refers to the branch path where the safety system or mitigation measures operate successfully as designed at a specific functional header; its probability represents system reliability. A failed branch refers to the branch path where the safety system or mitigation measures fail to operate as designed at a specific functional header; its probability represents system failure rate. Event tree analysis systematically expands these branches to ultimately quantify the probability of different consequence states, providing a basis for risk assessment and safety decision-making. Functional headers are located at the top of the event tree and describe the sequence of safety functions or systems that need to be responded to after the initiating event occurs. Functional headers can list mitigation systems or safety barriers arranged in chronological order, with each functional header corresponding to a binary decision point (success / failure), typically arranged from left to right in chronological order of action. For example, for a nuclear power plant loss-of-coolant accident, its functional headers may include: emergency core cooling system, containment spray system, containment isolation system, etc. The initiating event refers to the initial abnormal condition or disturbance that triggers the start of the event sequence; it is the first event leading to a potentially hazardous situation. Overall, an event tree typically consists of an initiating event and a function header. The function header is usually connected to the corresponding fault tree. When the initiating event occurs, a branch needs to be established at the function header to distinguish whether the function has failed or succeeded.

[0026] In some embodiments, step S10, calculating the minimum cut set and probability value of the failed branch of the function header includes: determining the input type of the function header; and calculating the minimum cut set and probability value of the failed branch based on the input type of the function header.

[0027] The input types for the function header include: basic events or fault trees. If the input type is a basic event, the minimum cut set and probability value of the failed branch are calculated as follows: the basic event is used as the minimum cut set of the failed branch; the assigned value of the basic event is used as the probability value of the failed branch. If the input type is a fault tree, the minimum cut set and probability value of the failed branch are calculated as follows: the minimum cut set and probability value of the failed branch are calculated using fault tree solving methods. Fault tree solving methods include, but are not limited to, any one of the following: the upward method, the downward method, and the binary decision graph method. Specifically, the input type of the function header corresponding to the successful branch may be either a basic event or a fault tree. If the input type is a basic event, the minimum cut set of its failed branch is the basic event itself, and its probability is the assigned value of the basic event. If the input type is a fault tree, the minimum cut set and probability value of the failed function header are calculated using fault tree solving methods. Commonly used fault tree solving methods include, but are not limited to, the upward method, the downward method, and the binary decision graph method. When calculating probabilities, an exact solution should be used. This requires either expanding the total probability formula or employing a disjoint cut-set approach, such as the binary decision graph method. For example, ... Figure 2As shown, in a specific example, IE is the initiating event, and FE1, FE2, and FE3 are three functional headers. Assume that the input to IE is a basic event A, the input to FE1 is an OR gate with inputs to basic events B and C, the input to FE2 is a basic event D, and the input to FE3 is an OR gate with inputs to B and E. The probabilities of A, B, C, D, and E are all assumed to be 0.1. Figure 3 This is the fault tree corresponding to the failure of the functional header FE1. The successful branch involved in sequence 2 is functional header FE1. Therefore, we solve for and quantify the minimum cut sets of functional header FE1 failure. The fault tree of functional header FE1 failure is transformed into a binary decision graph, yielding minimum cut sets B and C for functional header FE1 failure, with a failure probability of: B+B+ / BC = 0.1 + 0.9 0.1 = 0.19.

[0028] Step S20: Calculate the probability of the successful branch based on the probability value of the failed branch.

[0029] In some embodiments, step S20, calculating the probability of a successful branch based on the probability value of the failed branch, includes: subtracting the probability value of the failed branch from a set value to obtain a difference; and determining the difference as the probability of the successful branch. The set value is 1.

[0030] Specifically, the probability of a successful branch of the function header is obtained by subtracting the probability of the failed branch calculated in step S10 from 1. Similarly, using... Figure 2 For example, the probability of a successful branch of function FE1 is: 1 - 0.19 = 0.81.

[0031] Step S30: Transform the sequence containing the successful branch into a fault tree and calculate the minimum cut set of the sequence.

[0032] In some embodiments, step S30, converting the sequence containing successful branches into a fault tree and calculating the minimum cut set of the sequence, includes: ignoring the function headers of successful branches in the sequence; converting the sequence into a fault tree; associating the fault tree with the sequence; and after completing the association, calculating the minimum cut set of the fault tree; the minimum cut set of the fault tree is the minimum cut set of the sequence. Associating the fault tree with the sequence includes: determining the top event of the fault tree as the consequence of the sequence; setting an AND gate under the top event, with the input of the AND gate being the initial event and the input of the corresponding function header failure.

[0033] Specifically, for successful branches involved in the sequence, firstly, the function header is ignored, and the sequence is transformed into a fault tree; secondly, the top event of the fault tree is set as the consequence of the sequence, and an AND gate is set under this top event, with the input of the AND gate being the initial event and the input of the corresponding function header failure; then, the minimum cut set of the fault tree and its occurrence frequency are calculated. Similarly, with Figure 2 For example, Sequence 2, without considering the functional header FE1, is transformed into a fault tree as follows: Figure 4 As shown; then calculate the minimum cut sets of the fault tree, where the minimum cut sets of the fault tree are AB and AD.

[0034] Step S40: Reduce the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set.

[0035] In some embodiments, step S40, reducing the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set, includes: traversing the minimum cut set of the sequence according to the minimum cut set of the failed branch; if the minimum cut set of the sequence contains any minimum cut set in the minimum cut set of the failed branch, then obtaining a new minimum cut set by taking the corresponding minimum cut set in the minimum cut set of the sequence.

[0036] Specifically, based on the minimum cut set obtained in step S10, the minimum cut sets obtained in step S30 are traversed. If the minimum cut set in step S30 contains any of the minimum cut sets in step S10, the corresponding minimum cut set in step S30 is deleted, resulting in a new minimum cut set. Figure 2 For example, the minimum cut sets obtained in step S40 are AB and AD. The minimum cut set AB contains the minimum cut set B obtained in step S10. Therefore, the minimum cut set AB in step S30 is deleted, and a new minimum cut set AD is obtained.

[0037] Step S50: Calculate the frequency of the sequence based on the new minimal cut set.

[0038] In some embodiments, step S50 uses a first-order approximation algorithm, a limit approximation algorithm, or a binary decision graph algorithm to calculate the frequency of the sequence. Specifically, in embodiments of the present invention, a suitable method can be selected to calculate a new minimum cut set to obtain the frequency of the corresponding sequence. Figure 2 For example, the frequency of sequence 2 is: A D=0.1 0.1 = 0.01.

[0039] Step S60: Correct the frequency of the sequence by the probability of successful branching to obtain the target frequency of the sequence.

[0040] In some embodiments, step S60, modifying the frequency of the sequence by the probability of a successful branch to obtain the target frequency of the sequence, includes multiplying the probability of a successful branch by the frequency of the sequence to obtain the target frequency of the sequence.

[0041] Specifically, the frequency of the successful branch calculated in step S20 is multiplied by the frequency of the sequence calculated in step S50 to obtain a new frequency, which is the target frequency of the sequence. Figure 2 For example, multiplying the frequency of the successful branch of functional header FE1 (0.81) calculated in step S20 by the frequency of sequence 2 (0.01) calculated in step S50, we get: 0.81 0.01 = 0.0081, and this frequency value (0.0081) is the target frequency of sequence 2 (i.e. the final frequency of sequence 2).

[0042] refer to Figure 5 The present invention also provides a system for quantifying successful branching in an event tree.

[0043] Specifically, such as Figure 5 As shown, this event tree successful branch quantification system includes: The failure branch probability calculation unit 501 is used to obtain the function header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failure branch of the function header and the probability value of the failure branch.

[0044] Success branch probability calculation unit 502 is used to calculate the probability of a successful branch based on the probability value of a failed branch.

[0045] The sequence transformation unit 503 is used to transform a sequence containing a successful branch into a fault tree and to calculate the minimum cut set of the sequence.

[0046] The minimum cut set processing unit 504 is used to reduce the minimum cut set of the sequence based on the minimum cut set of the failed branch to obtain a new minimum cut set.

[0047] Sequence frequency calculation unit 505 is used to calculate the frequency of the sequence based on the new minimum cut set.

[0048] The frequency correction unit 506 is used to correct the frequency of the sequence by the probability of successful branching, so as to obtain the target frequency of the sequence.

[0049] Specifically, the specific coordination process between the units in the event tree successful branch quantification system can be found in the event tree successful branch quantification method described above, and will not be repeated here.

[0050] This invention fully considers the correlation between the sequence's minimum cut set and the minimum cut set of the failed functional header corresponding to the successful branch by removing the cut set from the sequence's minimum cut set. This ensures that the sequence's minimum cut set is a true minimum cut set. Simultaneously, by correcting the sequence frequency by multiplying the probability of the successful branch by the sequence frequency, it ensures that the final sequence frequency is not overestimated. This also avoids the complex calculations introduced by using De Morgan's full expansion for successful branches, achieving a balance between accuracy and efficiency.

[0051] Taking the aforementioned example, if existing technology is used, the error of the sequence reaches 135% or 90%, while the method of the present invention is basically close to the exact solution. At the same time, the calculation process is simple, which significantly improves the accuracy and efficiency of the calculation.

[0052] Furthermore, an electronic device according to the present invention includes a memory and a processor; the memory is used to store a computer program; the processor is used to execute the computer program to implement the event tree successful branch quantification method as described above. Specifically, according to embodiments of the present invention, the processes described above with reference to the flowchart can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowchart. In such embodiments, when the computer program is downloaded, installed, and executed by an electronic device, it performs the functions defined above in the methods of the embodiments of the present invention. The electronic device in the present invention can be a terminal such as a laptop, desktop computer, tablet computer, or smartphone, or it can be a server.

[0053] Furthermore, one type of storage medium of the present invention stores a computer program thereon, which, when executed by a processor, implements the event tree success branch quantification method described above. Specifically, it should be noted that the storage medium described above in the present invention can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In the present invention, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, wherein computer-readable program code is carried. The transmitted data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0054] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0055] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0056] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0057] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0058] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A method for quantifying successful branching in an event tree, characterized in that, Includes the following steps: Step S10: Obtain the function header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failed branch of the function header and the probability value of the failed branch; Step S20: Calculate the probability of the successful branch based on the probability value of the failed branch; Step S30: Convert the sequence containing the successful branch into a fault tree and calculate the minimum cut set of the sequence; Step S40: Reduce the minimum cut set of the sequence according to the minimum cut set of the failed branch to obtain a new minimum cut set; Step S50: Calculate the frequency of the sequence based on the new minimum cut set; Step S60: Correct the frequency of the sequence based on the probability of the successful branch to obtain the target frequency of the sequence.

2. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S10, calculating the minimum cut set of the failed branch of the functional header and the probability value of the failed branch includes: Determine the input type of the function header; The minimum cut set and probability value of the failed branch are obtained by calculating based on the input type of the function header.

3. The method for quantifying successful branching in an event tree according to claim 2, characterized in that, The input types for the function header include: basic events; If the input type of the function header is a basic event, then the minimum cut set and probability value of the failed branch are calculated in the following way: Use the basic events as the minimum cut set of the failed branches; The value of the basic event is used as the probability value of the failed branch.

4. The method for quantifying successful branching in an event tree according to claim 2, characterized in that, The input types for the function header include: fault tree; If the input type of the function header is a fault tree, then the minimum cut set and probability value of the failed branch are calculated in the following way: The minimum cut set and probability value of the failed branch are calculated using the fault tree solution method.

5. The method for quantifying successful branching in an event tree according to claim 4, characterized in that, The fault tree solution method includes any one of the following: the up-down method, the down-down method, and the binary decision graph method.

6. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S20, calculating the probability of the successful branch based on the probability value of the failed branch includes: The difference is obtained by subtracting the probability value of the failed branch from the set value; The difference is determined as the probability of the successful branch.

7. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S30, converting the sequence containing successful branches into a fault tree and calculating the minimum cut set of the sequence includes: For successful branches in the sequence, ignore their function headers; The sequence is converted into a fault tree; The fault tree is associated with the sequence. After the setup is complete, the minimum cut set of the fault tree is calculated; the minimum cut set of the fault tree is the minimum cut set of the sequence.

8. The method for quantifying successful branching in an event tree according to claim 7, characterized in that, The step of associating the fault tree with the sequence includes: The top event of the fault tree is identified as the consequence of the sequence; An AND gate is set under the top event, and the input of the AND gate is the input of the initiating event and the corresponding function header failure.

9. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S40, reducing the minimum cut set of the sequence based on the minimum cut set of the failed branches to obtain a new minimum cut set includes: Traverse the minimum cut set of the sequence based on the minimum cut set of the failed branches; If the minimum cut set of the sequence contains any minimum cut set in the minimum cut set of the failed branch, then the corresponding minimum cut set in the minimum cut set of the sequence is used to obtain the new minimum cut set.

10. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S50, the frequency of the sequence is calculated using a first-order approximation algorithm, a limit approximation algorithm, or a binary decision graph algorithm.

11. The method for quantifying successful branching in an event tree according to claim 1, characterized in that, In step S60, the frequency of the sequence is corrected based on the probability of the successful branch to obtain the target frequency of the sequence, including: The target frequency of the sequence is obtained by multiplying the probability of the successful branch by the frequency of the sequence.

12. A system for quantifying successful branching in an event tree, characterized in that, include: The failure branch probability calculation unit is used to obtain the functional header corresponding to the successful branch of the event tree, and calculate the minimum cut set of the failure branch of the functional header and the probability value of the failure branch. A successful branch probability calculation unit is used to calculate the probability of the successful branch based on the probability value of the failed branch; The sequence transformation unit is used to transform a sequence containing a successful branch into a fault tree and to compute the minimum cut set of the sequence. The minimum cut set processing unit is used to reduce the minimum cut set of the sequence based on the minimum cut set of the failed branch to obtain a new minimum cut set; A sequence frequency calculation unit is used to calculate the frequency of the sequence based on the new minimum cut set; A frequency correction unit is used to correct the frequency of the sequence based on the probability of the successful branch, thereby obtaining the target frequency of the sequence.

13. A storage medium, characterized in that, The storage medium stores a computer program adapted for loading by a processor to perform the steps of the event tree successful branch quantification method as described in any one of claims 1 to 11.

14. An electronic device, characterized in that, The device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the steps of the event tree successful branch quantification method as described in any one of claims 1 to 11 by invoking the computer program stored in the memory.

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