18 results about "Minimal cut set" patented technology

Methods for determining the reliability of a technical system using fault tree analysis, comprising the following steps: S1 - Defining basic events of fault tree analysis; S2 - for each basic event, defining a fuzzy linguistic variable and a set of membership functions; S3 - at least partially based on real-time embedded software, defines a minimal cutting set for linguistic fault tree analysis; S4 - at least partially based on the minimum intersection theorem, determining the reliability of the technical system. Furthermore, the invention relates to a control unit, vehicle system, a computer program product and a computer-readable medium for executing the method.

The invention discloses a multi-state network irregular minimum cut set vector identification and prevention method, which comprises the following steps: constructing a multi-state network according to an actual network system, and obtaining all minimum cut sets MC and demand levels d; according to the demand level, the edge maximum state and the minimum cut set capacity, whether repeated d-MCs exist or not is judged, and therefore the state upper limit of the edge under the minimum cut set is calculated in a self-adaptive mode; calculating a state lower limit of each edge in the multi-state network; based on a preset repetition-free d-MC search rule, searching for all candidate d-MCs; and carrying out authenticity verification on all the candidate d-MCs, rejecting unreal candidate d-MCs, and taking the remaining candidate d-MCs as real d-MCs. The method is applied to the field of reliability evaluation of the multi-state network, can eliminate the need of deleting a single step of repeating the d-MC, eliminates redundant conditions of non-real d-MC verification, and obviously improves the identification efficiency of the d-MC.

The invention provides a network security defense method based on a minimum cut set algorithm, and solves the technical problems that when a minimum cut set is searched for to determine a defense point in the prior art, key defense points are omitted due to the fact that all cut sets are not considered comprehensively, the response time is too long when a large-scale attack graph is processed, and security protection cannot be achieved in time. The method comprises the following steps: acquiring a vulnerability report and network configuration by a scanning system, generating an attack graph, and acquiring an equivalence formula of the attack graph from front to back according to an attacker and an attacker of the attack graph; replacing and expanding the equivalence formula from left to right, carrying out pruning operation, and then carrying out Cartesian product to obtain a minimum cut set; and finding out an intermediate expression in the equivalence formula, removing negative items in the intermediate expression and performing self-inspection, if a subset of the minimum cut set is included, performing Cartesian product after removing the subset, and merging into the minimum cut set to obtain a minimum defense strategy. The method can be widely applied to the technical field of network security.

The invention discloses a parallel cut set simplification method based on a fault tree logic embedded neural network, 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 amount is exponentially increased, the parallelization degree is insufficient, the efficiency is low due to dependence on explicit comparison, and efficient implementation on a GPU architecture is difficult, the invention provides an efficient cut set simplification scheme utilizing fault tree logic and neural network structure fusion. The method comprises the following steps of: vectorizing an initial cut set, grouping according to orders, generating a corresponding subset basic matrix, and generating'order minus one 'subset tensors in batches through an index mask; inputting the subset tensor into a fault tree logic equivalent neural network to execute parallel Boolean judgment, and outputting a result of whether the subset triggers a top event or not; according to judgment result slice statistics, non-minimum cut sets are quickly removed, and a minimum cut set is obtained. The method is suitable for reliability analysis and safety evaluation of large complex systems such as aerospace, nuclear power, rail transit and petrochemical devices.

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 relates to the field of fault tree analysis, in particular to a fault tree cut set solving method based on artificial intelligence. The method comprises the following steps: coding a fault tree into a structure matrix in a similar adjacent matrix form, and expressing an event and a cut set in a binary matrix form; searching the structure matrix to find out an analyzable intermediate event; analyzing each currently analyzable intermediate event through logic gate operation; performing a simplification operation on the analyzed intermediate event cut set, and only reserving a minimum cut set; after all parsable events searched in the round are parsed, rows and columns corresponding to parsed events in the middle event area of the structure matrix are deleted, and the next round of search is continued; and repeating the operation until the top event is analyzed. According to the method, the cut set is solved by adopting the matrix Boolean algebraic method, the fault tree analysis cut set simplification agent model is built based on the neural network, and the cut set is simplified in the solving process, so that the calculation efficiency of the minimum cut set is improved.

The application relates to a parallelized fault tree minimal cut set solving method based on bit set minimal cut set representation, and relates to the field of fault tree analysis. In order to solve the problems of redundant cut set data representation, insufficient parallelization degree, low calculation and storage efficiency and difficulty in supporting efficient solving of large-scale complex systems in the prior art, the method generates a standardized equivalent logical structure concise form fault tree by structurally simplifying and modularly decomposing a fault tree model; an intermediate event and a module solving queue are established according to a topological relationship; a multi-core parallel computing environment is established, a bit set is used to represent a cut set and a two-dimensional data array is formed; a bit-by-bit or broadcast operation is performed for an and gate, and row splicing and merging are performed for an or gate, so that parallel calculation of logical gate outputs is realized; and then non-minimal cut sets are screened out through parallel simplification, and a top event minimal cut set result is output. The application is suitable for fault tree analysis and fast solving of minimal cut sets of complex systems such as nuclear power, aerospace, chemical industry and rail transit.

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 application discloses a GO-FLOW-based system failure minimal cut set generation method, realizes common signal identification and renaming processing through GO-FLOW graph traversal search, obtains a minimal path set full set facing system task success, obtains a non-intersected minimal path set full set after deduplication through repeated signal decomposition in the minimal path set full set, obtains a system failure cut set combination according to signal negation and Boolean logic operation in the minimal path set full set, realizes repeated signal reconstruction analysis from bottom to top through binary tree reverse traversal according to the system failure cut set combination, realizes system modular minimal cut set full set generation in combination with inductive merging calculation of each subnode, and further realizes comprehensive analysis expression on the system success minimal path set and the system failure minimal cut set through signal renaming backtracking restoration and signal strength calculation for the modular minimal cut set.

The invention provides a cast-in-situ bored pile construction risk analysis method and system, and belongs to the technical field of risk identification, and the method comprises the following steps: determining a top event of a cast-in-situ bored pile construction risk by using an accident tree analysis method, analyzing an intermediate event and a basic event of an accident according to the top event, and constructing an accident tree; solving a minimum cut set of top events in the accident tree by using a Boolean algebraic method; drawing a dual tree of the accident tree by using duality of the minimum path set and the minimum cut set, and solving the accident tree by using a Boolean algebraic method to obtain the minimum path set of the top event; judging the structural importance degree of the basic event to the top event according to the occurrence frequency of the basic event in the minimum cut set or the minimum path set; and judging the risk factor of the top event through the minimum cut set, the minimum path set or the structural importance degree. According to the invention, the occurrence of accidents can be comprehensively analyzed, and prevention measures with strong pertinence are provided for avoiding the occurrence of accidents.

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 invention discloses a parallel fault tree minimum cut set solving method based on bit set minimum cut set representation, and relates to the field of fault tree analysis. In order to solve the problems that in the prior art, cut set data representation is redundant, the parallelization degree is insufficient, the calculation and storage efficiency is low, and efficient solving of a large-scale complex system is difficult to support, the method comprises the steps that structural simplification and modular decomposition are conducted on a fault tree model, and a standardized fault tree with an equivalent logic structure and a concise form is generated; establishing an intermediate event and module solving queue according to the topological relation; a multi-core parallel computing environment is established, a bit set mode is adopted to represent a cut set, and a two-dimensional data array is formed; executing bitwise OR broadcast operation for the AND gate, executing row splicing and merging for the OR gate, and realizing parallel calculation of logic gate output; non-minimum cut sets are screened out through parallel simplification, and a top event minimum cut set result is output. The method is suitable for fault tree analysis and minimum cut set rapid solution work of complex systems such as nuclear power, aerospace, chemical engineering, rail transit and the like.

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 present disclosure provides a link optimization method and device. The link optimization method comprises: establishing a topology model of an IP network; determining a plurality of minimal cut sets of the IP network according to the topology model of the IP network; determining an optimized link in each minimal cut set based on network reliability; determining an optimized link between a source node and a destination node in the IP network according to the optimized link in each minimal cut set; and performing an optimization process on the optimized link between the source node and the destination node. The present disclosure can effectively improve the performance of the IP network.

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.

The present invention discloses a method for obtaining the shortest interruption time under a certain fault tolerance number limit in a time-varying network. The method includes: obtaining a linear graph through a series of graph conversions for a given time-varying network; constructing a first integer programming model according to the linear graph; solving the minimum cut set of the network under the interruption time constraint in this model; substituting the preset network operation period, i.e., the longest interruption time, into the first model, and the obtained minimum cut set is the minimum spatial cost for cutting off the network; when the cardinality of the minimum cut set is not greater than the preset interruption number, constructing a second integer programming model according to the linear graph, and solving the shortest duration of a single connection interruption under the constraint of the interruption number; performing a binary search within the time range determined by the preset operation period, and converting the solution of the second model into the solution of the first model; each search verifies whether the first model has a solution for a given interruption time. If there is a solution, the upper limit of the time range is halved, and the search continues until the minimum time cost required to cut off the network is obtained.