15 results about "Minimum cut set" patented technology

The invention discloses a fault tree Boolean function equivalent mapping method based on an untrained neural network, and relates to the field of fault tree analysis. In order to solve the problems that in the prior art, a Boolean function mapping structure is not beneficial to parallel expansion, the calculation efficiency is limited, and the Boolean function mapping structure is difficult to efficiently realize on high-parallel platforms such as a GPU, the invention provides a method for generating topological structure data by analyzing a fault tree model; the basic events, the intermediate events and the top events are mapped into neurons of an input layer, a hidden layer and an output layer respectively, a feedforward network with fixed weight and bias is constructed, and a logic activation function is defined in nodes to realize Boolean logic propagation. The input layer receives a basic event state vector, outputs a top event result through forward propagation, and can realize large-scale Boolean function mapping on a parallel platform through batch input matrixes. The method is suitable for reliability analysis, minimum cut set simplification, top event probability calculation, parallelization fault tree solving and the like of a large-scale complex system.

The application discloses a truss size optimization design method based on minimum cut set correlation. The method comprises the following steps: establishing a balance matrix of the truss structure, using a zero space method to obtain a minimum cut set database of failure modes; constructing a joint failure model of the database, and then obtaining a failure probability under the consistency of the cut set edge probability space and establishing a reliability constraint optimization model; inputting the material density and length of each rod of the truss structure into the model, and outputting the optimized total weight and the cross-sectional area of each rod after processing, so as to perform size optimization design of the truss structure. The application solves the problems of failure mode combination explosion, insufficient correlation modeling and missing reliability constraints in the reliability analysis of the truss structure, can significantly reduce the complexity of the truss size optimization design, improve the structure failure probability evaluation precision, realize efficient and accurate system reliability evaluation and lightweight design, and has good computability and engineering applicability while ensuring the precision.

The invention discloses a parallelized cut set simplification method based on prime number compression coding, and relates to the field of fault tree analysis. In order to solve the problems that in the prior art, the cut set simplification calculation process is serialized, the parallel efficiency is low, a data structure is not matched with a GPU parallel architecture, and the minimum cut set of a large-scale complex system is difficult to efficiently solve, the method is provided to express the cut set in a fault tree model in a matrix mode in a binary vector form; grouping is carried out according to the number of events under the GPU parallel architecture; unique prime number codes are distributed for the basic events, the cut sets are converted into compressed integers, and division judgment of the inclusion relation of the cut sets is achieved; through matrix broadcasting and Boolean judgment matrix, large-scale parallelization subset identification is realized, and an effective cut set is dynamically updated in combination with an instant rejection mechanism, so that the calculation efficiency is remarkably improved, and the memory occupation is reduced. The method is suitable for system reliability evaluation and safety analysis work.

The invention discloses a matrix parallel computing method for solving a minimum cut set of a fault tree, and relates to the field of fault tree analysis. The matrix parallel computing method for solving the minimum cut set of the fault tree aims at solving the problems that in the prior art, the computing process is serialized, the parallel efficiency is low, a data structure is not matched with a GPU architecture, and the minimum cut set of the large-scale fault tree cannot be efficiently solved. According to the method, structured coding is carried out on a fault tree, and gate events and input relations are constructed into a structure description matrix; vectorizing the basic event and representing a candidate cut set of the intermediate event in a binary matrix form; under a GPU parallel architecture, row merging is performed on an OR gate, broadcast type combination is performed on an AND gate, parallel cut set simplification is performed, and meanwhile, a blocking and cache multiplexing strategy is introduced to improve the calculation throughput rate and reduce memory occupation. And carrying out loop iteration until the top event matrix is stable, and outputting a minimum cut set. The method is suitable for safety and reliability analysis of a large complex engineering system.

The invention provides a constellation system elasticity evaluation method comprising the following steps: S1, normalizing the coverage area of a constellation system in each working mode, and fitting to obtain a performance function; s2, determining the transfer type of the working mode, and determining the performance change condition of the constellation system before and after disturbance; s3, analyzing a minimum cut set Yk according to a preset fault tree; s4, calculating the elasticity of each minimum cut set Yk after an abnormal event occurs at the moment ti and a specific mode is implemented; s5, averagely taking m discrete time points from one work period of the constellation system, setting perturbation and the like to possibly occur at the m time points, and calculating the average projectile degree and the projectile degree satisfaction rate after a specific mode is implemented in the minimum cut set Yk; s6, calculating the average projectile degree and the projectile degree satisfaction rate of the minimum cut set Yk; s7, calculating the average elastic degree and the elastic degree satisfaction rate of the working mode transfer; and S8, calculating the average elastic degree and the elastic degree satisfaction rate of the constellation system.

The invention discloses a nuclear power accident information processing method and device, and the method comprises the steps: obtaining N pieces of nuclear power accident information corresponding to a target nuclear power accident final state, and each piece of nuclear power accident information comprises an originating event and a function event; obtaining fault tree information corresponding to each piece of nuclear power accident information according to each piece of nuclear power accident information; calling a plurality of working nodes to carry out parallel processing on the N pieces of fault tree information to obtain a minimum cut set corresponding to each piece of fault tree information; and combining the obtained minimum cut sets corresponding to the multiple pieces of fault tree information to obtain a global minimum cut set of the target nuclear power accident final state, in the steps, parallel independent calculation of the nuclear power accident information can be performed, the overall efficiency is improved, the local minimum cut sets obtained through distributed calculation are efficiently combined, the global minimum cut set is generated, and the overall efficiency of the target nuclear power accident final state is improved. The required set can be quickly obtained, and subsequent safety evaluation is facilitated.

The invention discloses a mechanical arm vacuum circuit fault diagnosis and self-healing system and method, relates to the technical field of industrial robot adsorption execution, and solves the problems that vacuum circuit abnormity lacks a traceable diagnosis mechanism, fault recognition is inaccurate and no self-healing strategy support exists. In combination with AND gate / OR gate trigger logic and a minimum cut set recursive expansion technology, the vacuum system has a complete and clear fault conduction path, so that system-level anomaly can be accurately mapped to a bottom layer physical root cause, the structured traceability which cannot be achieved by a traditional method is realized, deviation caused by artificial experience judgment is effectively reduced, and the reliability of the system is improved. And the fault positioning accuracy and diagnosis efficiency are improved.

The invention provides a design method and device of a magnetically controlled reactor step type alternating current and direct current pulse hybrid controller, and belongs to the technical field of magnetically controlled reactor step type alternating current and direct current pulse hybrid controllers. An inverter circuit and a filter circuit are configured to realize controllable AC voltage output, a nanometer biphase composite magnetic material magnetizing control mode is established, a DC magnetizing process is realized through IGBT switch tube control, a graph theory minimum cut set-based stepped AC demagnetization optimization strategy is constructed, and stable magnetizing and demagnetization switching is realized by solving an optimal switch sequence. A self-adaptive control strategy based on a magnetization state prediction model is implemented, a hierarchical attention network is adopted to predict a magnetization state change trend in a magnetizing and demagnetizing switching process, and a dynamic parameter adjustment function is combined to optimize control parameters; the technical problem that accurate magnetization state control cannot be achieved in the direct current magnetization and alternating current demagnetization switching process of the magnetically controlled reactor is solved.

The invention provides a fault tree design method and system based on a graphical interface, a storage medium and a program product, and relates to the technical field of computers.The method comprises the steps that a fault tree graphic model created when a target user conducts target interaction operation on the graphical interface is obtained; performing multi-dimensional verification on the model to generate a multi-dimensional verification result, distributing a unique prime number identifier for each bottom event in the model after the multi-dimensional verification is passed, and establishing a mapping relationship between the bottom events and prime numbers; equivalently converting preset non-standard logic gates except an AND gate and an OR gate in the model to obtain a standardized fault tree model, and generating a cut set matrix according to the standardized fault tree model; determining a cut set prime product sequence of the cut set matrix by using the mapping relation, performing division detection on the sequence, and removing cut sets corresponding to prime products divided by other prime products in the sequence to obtain a minimum cut set set; and displaying a fault tree design result comprising the fault tree graphic model, the minimum cut set and the multi-dimensional verification result by utilizing a graphic interface.

The application discloses a diesel engine reliability evaluation method based on a repairable dynamic fault tree, which simultaneously considers the maintenance and fault dynamic characteristics of a diesel engine system when modeling the reliability of the diesel engine system, adopts a repairable dynamic fault tree, is designed based on a repairable system probability state transition model, can simultaneously consider the maintenance and fault dynamic characteristics of a Markov type repairable system, and has the advantages of short running time, simple analysis steps and the like.In addition, the application adopts a Markov model to deduce a quantitative calculation formula, and finally can obtain a transient availability change curve of the diesel engine system, so as to obtain quantitative analysis of the reliability of the system, and two kinds of qualitative analysis of the reliability of the minimum cut set of the fault tree and the maintenance importance of the components.According to the qualitative analysis result, the maintenance importance of the components is calculated again by using a multi-criteria compromise solution sequencing method, the weak link of the diesel engine electronic control system is judged through comprehensive analysis, and therefore more accurate guidance is provided for the design and maintenance of a new diesel engine system.

The invention discloses a truss size optimization design method based on minimum cut set correlation. The method comprises the following steps: establishing a balance matrix of a truss structure, and obtaining a minimum cut set database of a failure mode by using a null space method; the method comprises the following steps: constructing a joint failure model of a database, obtaining a failure probability and establishing a reliability constraint optimization model under the condition of keeping cut set marginal probability space consistency, inputting the material density and length of each rod piece of a truss structure into the model, and outputting the optimized total weight and the sectional area of each rod piece after processing. And the size optimization design of the truss structure is carried out. According to the method, the problems of failure mode combination explosion, insufficient correlation modeling and reliability constraint deficiency in design in reliability analysis of the truss structure are solved, the complexity of truss size optimization design can be remarkably reduced, the structure failure probability evaluation precision is improved, efficient and accurate system reliability evaluation and lightweight design are achieved, and the method is suitable for popularization and application. And the method has good computability and engineering applicability while ensuring the precision.

This invention discloses a method for predicting GIS equipment failure risk based on minimum cut set probability propagation. The method includes acquiring GIS equipment structural information, constructing a fault tree model containing top events, intermediate events, and bottom events, and performing qualitative analysis to determine the minimum cut set corresponding to the top event. Combining historical failure information of the basic components corresponding to each bottom event, the method calculates the weighted failure rate and failure probability, and performs probability propagation based on the minimum cut set structure to obtain the occurrence probability of each minimum cut set and its risk contribution to the top event. An adaptive threshold is used to identify the dominant failure mode. Real-time operating status information of each basic component is acquired, a bottom event status deviation index is constructed, the failure probability of bottom events is dynamically corrected, and the occurrence probability of the dominant failure mode is updated to predict the real-time failure risk of the GIS equipment. This invention can integrate historical and real-time data to achieve dynamic assessment of equipment failure risk, improving prediction accuracy and operational reliability.

The invention belongs to the field of aviation airborne system safety modeling and analysis, and particularly relates to a power generation system safety evaluation method based on a SysML correction model. Comprising the following steps: generating a SysML model; establishing a functional logic model by reading the SysML model of the system; adding a failure state on the basis of the function logic model to carry out fault analysis and establish a fault propagation model; establishing a mathematical model, a system architecture, a fault model, a transient / steady-state fault monitoring model and a fault simulator of the power generation system, forming a fault propagation relation analysis model of the power generation system, and judging a minimum cut set of a failure state according to the fault propagation relation analysis model; correcting the fault propagation model through the minimum cut set of the failure state and the influence of the fault on the local part, the higher level, the adjacent level and the system output; and performing model-based reliability and safety design analysis according to the corrected fault propagation model, generating a fault tree model of the power generation system, and performing power generation system safety assessment according to the fault tree model.

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.

The application provides a network security defense method based on a minimum cut set algorithm, and solves the problems that when seeking a minimum cut set to determine a defense point, all cut sets are not comprehensively considered, resulting in missing key defense points, and when processing a large-scale attack graph, the response time is too long, and the security protection cannot be realized in time. It includes the following steps: a scanning system obtains a vulnerability report and a network configuration, generates an attack graph, and obtains equivalent formulas of the attack graph from front to back according to attackers and attacked persons of the attack graph; the equivalent formulas are replaced and expanded from left to right, pruned, and then subjected to Cartesian product to obtain a minimum cut set; intermediate expressions are found in the equivalent formulas, negative terms in the intermediate expressions are removed and self-checked, if a subset of the minimum cut set is contained, the subset is removed, subjected to Cartesian product, and incorporated into the minimum cut set to obtain a minimum defense strategy. The application can be widely applied in the field of network security technology.