35 results about "Discrete event system" patented technology

The invention relates to the technical field of intelligent manufacturing, and discloses an intelligent control method and system for a stamping robot, and the method comprises the steps: constructing a knowledge graph containing the multi-dimensional relation of the quality of material technology equipment; the process knowledge is converted into a formalized logic rule, and the formalized logic rule is fused with a deep neural network to construct a neural symbol inference model; modeling the stamping process into a discrete event system, and verifying the correctness of a process control rule by using a linear temporal logic protocol; detecting and solving parameter constraint conflicts in the process control rule by using a satisfiability model theory solver; generating and executing a self-adaptive stamping control strategy based on the verified rule base and production process feedback; according to the method, symbol reasoning and deep learning are fused, the technical characteristics of high interpretability, high safety, high adaptive capacity and the like are achieved, and the quality consistency and production efficiency of stamping production can be effectively improved.

The invention discloses a CPPS-based interaction mechanism modeling method and system, and the method comprises the steps: collecting the data of a power grid system and an information system through an intelligent electric meter and a sensor, determining key connection points and paths between a power system and the information system through a graph theory and a complex network theory, carrying out the modeling of a coupling event through a discrete event system, and carrying out the modeling of the coupling event. The dynamic relationship between the information event and the physical event is described, and the stability and toughness of the system are evaluated by simulating and calculating the system response under different scenes. Therefore, comprehensive monitoring of the operation condition of the power grid system is realized, high-quality and real-time data support is provided for subsequent analysis and optimization, and the reliability and timeliness of data-driven decision making are ensured. The structural transparency and predictability of the power grid are enhanced, targeted maintenance and optimization for key nodes and paths are facilitated, and the overall efficiency and safety of the system are improved.

The invention provides a random discrete event system active opaqueness-based position information hiding method, which comprises the following steps of: modeling a position information hiding system into a random discrete event system, constructing a k-step active opaqueness verifier VG according to a modeled mathematical model, and further constructing a Markov chain M, calculating the probability of exposing the secret position after each position information hiding scheme is forced to be executed, judging whether the probability corresponding to at least one position information hiding scheme is smaller than a preset threshold value or not, if so, determining that the mathematical model of the random discrete event system has random k-step active opaqueness, and completing hiding of the position information; otherwise, regenerating a new position information hiding scheme; according to the method, multiple sets of position information hiding schemes are preset at the same time, active control is introduced into opaqueness research, k-step active opaqueness is verified, the opaqueness control capacity is improved, the active opaqueness application range is widened, and reliable hiding of position information can be effectively achieved.

The invention discloses a system security real-time verification method and system for a discrete event system, and the method comprises the steps: building a Time Labled Petri Nets model of the discrete event system according to the information of the discrete event system, and enabling the information of the discrete event system to comprise an event, a tag and time information; for the Time Labled Petri Nets model of the discrete event system, using the real-time observation expression of the discrete event system and the expression of the initial secret state of the discrete event system to obtain the real-time observation of the discrete event system and the initial secret state of the discrete event system; constructing an integer linear programming mathematical problem model according to the discrete event system verification real-time security constraint condition; substituting the real-time observation of the discrete event system and the initial secret state of the discrete event system into the integer linear programming model to solve and verify the security of the integer linear programming model to obtain a verification result; and judging the security of the discrete event system according to a verification result.

The application discloses a kind of supervision control strategy generation methods based on counterexample guide deep reinforcement learning, comprising: one, definition model;Two, supervision control strategy generation, the method with deep Q network as reinforcement learning subject, introduce online counterexample guide verification mechanism, using counterexample search dynamic correction control permission dictionary and optimizing reinforcement learning strategy, finally coupling convergent deep network parameters and whole state space dynamic permission dictionary, generate with global non-blocking characteristics coordinated supervision control strategy.This method can meet non-blocking and approach maximum allowable supervision strategy without explicitly constructing the global state space of controlled discrete event system, balance between computational complexity and strategy allowance, provide a new technical approach for non-blocking control of super large scale discrete event system.

The present application provides a system security verification method, verification system and terminal device, which constructs a discrete event system model by abstracting an information-physical system at the dynamic logic level; in this model, the change of the system state is driven by the asynchronous triggering of discrete events. In the present application, a state attack refers to the ability of an external intruder to launch a state attack on the system, and to accurately determine whether the current state of the system is affected by the attack based on the information obtained after the attack; when there is no state attack, the current state of the system is reasonably estimated by analyzing the event sequence generated by the system, thereby verifying the security of the system. Therefore, the present application can use the event sequence that occurs in the system and the attack sequence that may be obtained by the external intruder to reasonably infer the current state of the system, thereby effectively verifying the security of the system when it is attacked by the state.

The invention discloses a dual-time Petri network system activity control method based on time parameter adjustment. The method comprises the following steps: establishing sufficient and necessary conditions of activity violation caused by improper configuration of time parameters of a system; constructing a plurality of parameter adjustment options considering the adjustment cost, wherein the parameter adjustment options are used for modifying static time parameters of the system; two parameter adjustment strategies based on cost are provided, active violation existing in the system is recursively processed, that is, feasible time parameter configuration is iteratively synthesized and the overall adjustment cost is minimized by focusing on eliminating a specific active violation in each iteration step. The two strategies verify the validity of the generated solutions; the single-option adjustment strategy verifies the solutions corresponding to the single adjustment options one by one, and selects the feasible option with the minimum cost for iteration; according to the multi-option adjustment strategy, a parameter optimization problem corresponding to single activity violation is modeled into a linear programming model, and a feasible solution is solved to realize multi-parameter collaborative optimization. The invention provides a technical scheme of time parameter regulation and control based on a dual-time Petri network for a discrete event system with complex time constraint, and can effectively realize formalized verification and guarantee of system activity.

The invention relates to a particle filtering concurrent sampling method and device based on a thread pool and computer equipment. The method comprises the following steps: in an initialization stage, creating a thread pool and a task queue by a main thread; after initialization is completed, a plurality of calculation tasks are created by a main thread, the calculation tasks, task queues and threads are abstracted into a multi-service-desk single-queue queuing system which is described in a normative and formalized mode by adopting a discrete event system, and the multi-service-desk single-queue queuing system is based on the states of calculation task queues and thread request queues in the task queues. Idle threads are dynamically dispatched and allocated to execute the calculation tasks, and concurrent execution of the calculation tasks is achieved; wherein the calculation task is a particle filtering sampling task in microscopic simulation. According to the method, the execution efficiency of particle filtering sampling and the operation efficiency of microscopic simulation are improved through concurrent execution of calculation tasks, certain resource consumption and calculation amount are reduced, the real-time requirement of dynamic data driving simulation is guaranteed, and therefore better simulation performance is achieved.

The present invention relates to a lossless event compression method based on a discrete event system, including obtaining a minimum recoverable compressed event sequence given a discrete event system and a source event sequence generated by the system; given a first compression protocol: retaining the last k events in the source event sequence; given a second compression protocol: retaining at least one event for any cyclic sub-event sequence, establishing a compression automaton model to represent all possible source event sequences of the given compressed event sequence, detecting whether the given compressed event sequence is 1-order recoverable and whether it satisfies the second compression protocol based on the compression automaton model, and respectively proposing an offline lossless event compression method and an online lossless event compression method. The present invention utilizes the information redundancy generated dynamically by the system as a compression method based on the system, reduces storage resources, and ensures that all actions occurring in the system can be tracked while saving fewer actions.

The invention relates to a method, implemented by a computer infrastructure, for controlling the sequential change in a resource of a discrete event system, said change being modelled by a state machine having a plurality of states and at least one transition for changing the current state of the resource from a first state to a second state on the occurrence of a predefined event, the method comprising the following steps: reading a first computer object representing the resource, said first computer object describing the current state of the resource and comprising a function that is intended to be executed automatically by the computer infrastructure in the event of a request to change the current state of the resource from the first state to the second state; executing the function associated with the requested state transition from the first state to the second state.

The invention provides a reliable fault diagnosis method for a random discrete event system and application thereof, and the method comprises the steps: firstly, defining a dynamic observation activation method for the random discrete event system; secondly, according to formalization-reliable dispersion diagnosability of the dynamic observation activation method, a local random-diagnostor is constructed for each local site according to the dynamic observation activation method; and finally, constructing a reliable-co-diagnostor according to the local random-diagnostor, verifying the reliable dispersive diagnosability of the random discrete event system according to the reliable-co-diagnostor, and performing reliable dispersive diagnosis of the random discrete event system under an observation activation method, reliable diagnosis is popularized from a discrete event system to a random discrete event system, and an observation activation method is introduced to realize dynamic switching of a sensor so as to optimize configuration, so that the robustness of the system under the scenes of sensor failure, network congestion and the like is remarkably improved.

The application discloses a parallel time sequence advancing method and electronic equipment suitable for discrete event system simulation, and comprises the following steps: starting a main program of simulation deduction, and updating an event queue list; according to time stamps of sequence events in the updated event queue list, calling resources corresponding to the sequence events on demand, and executing subprograms of the sequence events; after receiving a mutation state signal, generating a random event according to the mutation state signal, and setting a time stamp and a highest priority of the random event; according to the time stamp and the highest priority of the random event, adopting a triggered event parallel response method, and executing a subprogram of the random event; after executing the subprogram of the random event, continuing to execute the subprograms of the sequence events in the event queue list until the main program of simulation deduction is ended, and generating a simulation report. The application simultaneously satisfies a hybrid execution logic of script type prefabricated execution and event triggered generation and parallel response execution at any moment, and improves flexibility and randomness of a military simulation deduction system.

The present invention discloses a real-time system security verification method and system for a discrete event system. The method comprises the following steps: establishing a Time Labeled Petri Nets model of the discrete event system based on discrete event system information, wherein the discrete event system information includes events, labels, and time information; applying a real-time observation expression of the discrete event system and an expression of an initial secret state of the discrete event system to the Time Labeled Petri Nets model of the discrete event system to obtain real-time observations of the discrete event system and an initial secret state of the discrete event system; constructing an integer linear programming mathematical problem model based on constraint conditions for verifying real-time security of the discrete event system; introducing the real-time observations of the discrete event system and the initial secret state of the discrete event system into the integer linear programming model for solving and verifying the security of the integer linear programming model to obtain a verification result; and judging the security of the discrete event system based on the verification result.

The invention belongs to the technical field of information security, and relates to a smart home temperature control system opacity strengthening method based on a tag time Petri network. Establishing a label time Petri network model of the intelligent household temperature control system; constructing a partial correction state class diagram based on time sequence observation of which the current state is not transparent, forming a path constraint model consistent with observation logic, and identifying a path set inconsistent with observation time; screening a path which meets the opaqueness of the current state relative to the secret identifier set in the path set, and constructing a linear programming model to solve a minimum time sequence disturbance function value; and updating the original time sequence observation by using the perturbation function, and generating a new observation sequence meeting the opaqueness of the current state. According to the method, an attacker is effectively prevented from deducing the real state of the system through a time sequence, meanwhile, exhaustive search on a full-state space is avoided, the calculation complexity is reduced, and the applicability and expandability of the method in a complex discrete event system are improved.

This invention discloses a method for quantifying the current state opacity of discrete event systems, belonging to the technical field of current state opacity quantification for discrete event systems. The method involves constructing a resource automaton model and a resource intruder model based on a nondeterministic finite state automaton, and further constructing a resource game theory model on this basis. Game theory is then introduced to quantify the current state opacity of the discrete event system. This invention can achieve accurate quantification of the current opacity of discrete event systems, adapting to environments where system behavior has inherent uncertainty and faces proactive analysis by intelligent attackers. It can also maximize its own utility and meet the needs of refined evaluation of system privacy and security in practical applications.

This invention relates to a differential privacy enhancement method for a discrete event system in a smart building, comprising: obtaining the initial resource configuration of the smart building system; representing the initial resource configuration using a probabilistic automaton; and establishing a differential privacy mechanism for the smart building system; calculating the probability distribution of the smart building system's behavior under similar initial resource configurations using a differential privacy verifier; verifying whether the smart building system satisfies the differential privacy mechanism using the probability distribution; if it does not satisfy the differential privacy mechanism, calculating a replacement function for the smart building system; and using the replacement function to control the probabilistic automaton to replace the observation symbols of system events. This invention ensures that attackers cannot infer the current initial resource configuration information of the system through external observation.

The invention relates to a differential privacy enhancement method for an intelligent building discrete event system, and the method comprises the steps: obtaining the initial resource configuration of an intelligent building system, representing the initial resource configuration through a probability automaton, and building a differential privacy mechanism of the intelligent building system; calculating probability distribution of behaviors of the intelligent building system under similar initial resource configuration by using a differential privacy verifier; and verifying whether the intelligent building system meets a differential privacy mechanism or not by utilizing the probability distribution, if the intelligent building system does not meet the differential privacy mechanism, calculating a replacement function of the intelligent building system, controlling the probability automaton by utilizing the replacement function, and replacing the observation symbol of the system event. The method can ensure that an attacker cannot speculate the current initial resource configuration information of the system through external observation.

The invention discloses a system information security judgment and protection method based on a concurrent synthesis operator. The method is based on a brand new technology of a concurrent synthesis operator, and specifically comprises the following steps: constructing a discrete event system under an incomplete information condition as an automaton model; constructing a non-secret sub-automaton of the automaton model; in order to estimate the current state of the non-secret sub-automaton, a state observer model of the non-secret sub-automaton is given; performing concurrent synthesis operation on the original system and the state observer model of the non-secret sub-automaton to obtain an information structure based on concurrent synthesis; based on the information structure, whether the discrete event system has the strong opaque property based on the state or not can be judged, and the proposed new enhancement mechanism can protect the leaked secret state. According to the technical scheme of the invention, the verification and protection of the state-based strong opaque property of the discrete event system under the incomplete information condition are realized through a concurrent synthesis operator method.

The application belongs to the technical field of fault diagnosis of discrete event systems, and particularly relates to a research method of fault diagnosis of discrete event systems based on a lambda-free Petri net, which comprises the following steps: S1: constructing a labeled lambda-free Petri net model for a discrete event system; S2: judging whether a fault can be detected through an observation sequence with a limited length, that is, whether the system is diagnosable; S3: if the system is not diagnosable, then a verification net is constructed on the basis of the original Petri net, the reachable tree thereof is unfolded and pruned by using the system structure captured in the verification net, and labels that need to be relabeled are searched. The application can help to improve the efficiency and accuracy of fault diagnosis, and the Petri net model after removing empty transitions can reduce the complexity of system description, thereby simplifying the fault diagnosis process.

The invention discloses a discrete scheduling-oriented hierarchical timing Petri net deduction simulation and conflict resolution method. The method comprises the following steps of: realizing hierarchical modeling of a discrete task; specifically, a hierarchical timing Petri net model is composed of a place, transition, a flow relation, place time delay, transition time delay, an identifier and a mapping function, hierarchical modeling of discrete tasks is achieved, a subtask hierarchical timing Petri net and a meta-task hierarchical timing Petri net are included, the former shows operation logic of a composite task on a subtask level, and the other shows operation logic of the composite task on a meta-task level. The latter shows specific execution steps of the composite task at the meta-task level; an execution library in the sub-task level timing Petri net can be mapped into a meta-task timing sub Petri net in the meta-task level through a mapping function; the hierarchical timing Petri net model takes a discrete task scheduling result as input, realizes dynamic conflict resolution of the discrete task scheduling result in a deduction simulation process, and is particularly suitable for simulation of discrete event systems such as intelligent manufacturing tasks, intelligent logistics processes, industrial automation system cooperative control and the like.

The invention discloses a method for predicting a robust fault of a random discrete event system under observation loss, and the method comprises the following steps: constructing a random robust verifier of a random automaton of a manufacturing system, obtaining the state of each operation stage of the manufacturing system and the operation and fault of the manufacturing system, constructing an event set based on a monitoring sensor group of the manufacturing system, and predicting the fault of the random discrete event system. The random robust verifier synchronizes an observation permanent loss scene of the adaptive event set; collecting a boundary state set of a random robust verifier; and screening a boundary state and a reachable part of a state reached by another path event string matched with the event string projection of the boundary state, outputting a ring type of the reachable part, judging random robustness predictability, and outputting a fault prediction result. According to the method, the problem of event observation loss caused by sensor faults, signal transmission interference and the like in an actual scene can be effectively solved, stochastic discrete event system fault prediction can be accurately realized, the limitation of observation loss scenes is broken through, and stochastic discrete event system fault prediction requirements are met.

The present invention relates to the field of intelligent manufacturing technology, and discloses an intelligent control method and system for a stamping robot. Among them, an intelligent control method for a stamping robot includes: constructing a knowledge graph containing the multi-dimensional relationship of material process equipment quality; transforming process knowledge into formal logical rules and fusing with a deep neural network to construct a neuro-symbolic reasoning model; modeling the stamping process as a discrete event system and using linear temporal logic specification to verify the correctness of process control rules; using a satisfiability modulo theory solver to detect and resolve parameter constraint conflicts in process control rules; generating and executing an adaptive stamping control strategy based on the verified rule base and production process feedback; The present invention combines symbolic reasoning and deep learning, has technical characteristics such as strong interpretability, high safety, and strong adaptability, and can effectively improve the quality consistency and production efficiency of stamping production.

The application discloses a fault diagnosis method for a discrete event system based on events and partially observable states, and comprises the following steps: S1, acquiring a discrete event system to be diagnosed, and modeling the discrete event system into a deterministic finite state automaton, wherein observable behaviors of the discrete event system comprise an observable event set and an observable output set; S2, defining event-output pairs based on the automaton; S3, defining observable event-output pairs and observable event-output pair sequences composed of the observable event-output pairs based on the event-output pairs; S4, constructing a verifier automaton taking the observable event-output pairs as events, wherein states of the verifier automaton carry information about whether the discrete event system is faulty; and S5, judging whether the discrete event system is diagnosable. The application realizes effective diagnosis of the diagnosability of a system under the condition that both events and states are partially observable.

The invention belongs to the technical field of discrete event system fault diagnosis, and particularly relates to a discrete event system fault diagnosis research method based on a lambda-free Petri net, and the research method comprises the following steps: S1, constructing a label lambda-free Petri net model for a discrete event system; s2, judging whether the occurrence of a fault can be detected through an observation sequence with a finite length, namely, whether the system has diagnosability or not; and S3, if the system is not diagnosable, constructing a verification network on the basis of the original Petri network, expanding and trimming a reachable tree by using a system structure captured in the verification network, and searching a label needing to be marked again. According to the method, the efficiency and accuracy of fault diagnosis can be improved, and the complexity of system description can be reduced by the Petri network model after the null transition is removed, so that the fault diagnosis process is simplified.

The application provides a position information hiding method based on random discrete event system active opacity, which comprises the following steps: modeling a position information hiding system as a random discrete event system, and constructing a k-step active opacity verifier V according to a mathematical model of the modeling G , further constructing a Markov chain M, calculating a probability of exposing a secret position after each position information hiding scheme is enforced, judging whether there is at least one position information hiding scheme corresponding to a probability less than a preset threshold, if yes, the mathematical model of the random discrete event system has random k-step active opacity, and the position information hiding is completed; otherwise, a new position information hiding scheme is generated; the application simultaneously presets multiple position information hiding schemes, introduces active control into the opacity research, verifies the k-step active opacity, improves the control ability of the opacity, widens the application range of the active opacity, and can effectively realize reliable hiding of the position information.

The invention provides a system security verification method, a verification system and terminal equipment, and the method comprises the steps: carrying out the abstraction processing of a dynamic logic layer on an information physical system, and constructing a discrete event system model; in the model, the change of the system state is driven by asynchronous triggering of discrete events, and in the application, the state attack means that an external intruder can initiate a state attack on the system and can accurately judge whether the current state of the system is affected by the attack according to information acquired after the attack; and when the state attack does not exist, the current state of the system is reasonably estimated by analyzing the event sequence generated by the system, so that the security of the system is verified. Therefore, the current state of the system can be reasonably deduced by using the event sequence generated by the system and the attack sequence possibly acquired by an external intruder, so that the security of the system when the system is subjected to state attack is effectively verified.

The invention belongs to the field of discrete event system control, intelligent manufacturing and reinforcement learning, and discloses a state feedback control strategy generation method and system of a time delay Petri network system in a non-deterministic environment, and the method comprises the steps: constructing a time delay Petri network model containing controllable / uncontrollable transition and minimum transmission delay constraint, defining a time extension state formed by the identification and the enable transition residual delay; a two-stage random judgment mechanism is introduced, two types of non-deterministic factors of control execution errors and uncontrollable event preemption are modeled, and the state transition probability is deduced; a control problem is formalized into a Markov decision process, and a reward function with time consumption as a negative reward and deadlock and an ultra-long path as strong punishment is designed; and adopting a table type Q learning algorithm based on dynamic learning rate scheduling, iteratively updating an action value function in interaction with a simulation environment, and exporting a state feedback control strategy. The method can be widely deployed in discrete event system control scenes such as flexible manufacturing, logistics scheduling and multi-robot cooperation.

The invention discloses a high-throughput-oriented period scheduling method, and belongs to the technical field of industrial production period scheduling. The method comprises the following steps: inputting production data, wherein the production data comprises operation area division information, equipment information and process flow information of process processing; constructing a technological process automaton model for each technological process based on a discrete event system supervision and control simulation platform, and generating non-deadlock candidate scheduling paths meeting technological requirements by taking operation areas, technological steps and equipment as scheduling path nodes; taking the candidate scheduling path with the shortest total processing time length of each production cycle as an optimal scheduling path; and dispatching information is distributed to each corresponding operation device in the operation area based on the optimal dispatching path, so that the processing operation of the processing object is executed based on the received dispatching information. According to the method, the equipment utilization rate can be maximized, the production period is shortened, and smooth connection of all process stages is ensured; and the production efficiency is ensured, and the resource utilization maximization is realized at the same time.

The present application relates to a particle filter concurrent sampling method, apparatus, and computer device based on a thread pool. The method includes: in the initialization phase, the main thread creates a thread pool and a task queue; after initialization is completed, the main thread creates a number of computing tasks, and abstracts the computing tasks, the task queue, and the threads into a multi-server single-queue queuing system formalized by discrete event system specifications. Based on the states of the computing task queue and the thread request queue in the task queue, the system dynamically schedules and allocates idle threads to execute the computing tasks, realizing the concurrent execution of the computing tasks; wherein, the computing tasks are particle filter sampling tasks in microscopic simulation. This method improves the execution efficiency of particle filter sampling and the running efficiency of microscopic simulation through the concurrent execution of computing tasks, reduces certain resource consumption and computational amount, and ensures the real-time requirements of dynamic data-driven simulation, thereby achieving better simulation performance.

The invention discloses a construction method of an energy management system information estimator based on data driving. The method comprises the following steps: 1, defining a model; 2, constructing an information estimator; according to the technical scheme, the dependence of traditional supervision and control on an accurate model is broken through, state and income joint estimation is realized under partially considerable and model-unknown conditions, and a feasible technical scheme is provided for quantitative control of complex discrete event systems such as a high-performance energy management system. The method can support optimal supervision control strategy synthesis of energy benefit management in a model-free and partially considerable environment.