5 results about "Risk theory" patented technology

The invention relates to the technical field of disaster assessment, and discloses a tree lodging risk assessment method and device based on a disaster risk theory. The assessment method comprises the following steps: acquiring a basic data set for disaster risk assessment; and inputting the basic data into a pre-constructed tree lodging risk index calculation model, and calculating and outputting a predicted tree lodging risk index. According to the embodiment of the invention, the assessment precision is improved: real-time and future predicted risk reminding is carried out by establishing a quantitative tree lodging risk index, and the precision and accuracy of disaster risk assessment are improved; overall-process risk prompting is realized; overall-process dynamic risk prompting is carried out around historical, real-time and future key time points, so that the disaster response efficiency is improved; and through more accurate disaster assessment and early warning, the landscaping maintenance cost and loss are reduced, and the social benefit of disaster response is improved.

The invention discloses a power grid probabilistic power and electric quantity balance risk assessment method and system, and relates to the technical field of power systems, and the method comprises the steps: employing an affine strategy as an adjustment means for a thermal power generating unit to cope with a wind and light prediction error, and defining the up and down adjustment demands of a power grid and the up and down climbing standby adjustment capability provided by the thermal power generating unit; based on a probability theory, defining a power grid probabilistic power and electric quantity balance risk; and based on a conditional value-at-risk theory, providing load shedding power and power abandoning power risk indexes of the power grid under a certain confidence probability, and performing evaluation. According to the power grid probabilistic power and electric quantity balance risk assessment method provided by the invention, an affine strategy is adopted as an adjustment means for a thermal power generating unit to cope with a wind-solar prediction error; based on a probability theory and a conditional value-at-risk theory, load shedding power and abandoned power risk indexes of the power grid under a certain confidence probability are proposed, and the power and electric quantity balance risk of the power grid under a high-proportion new energy scene can be accurately quantified.

The invention relates to the technical field of power supply optimization, in particular to a vulnerability optimization method for nodes in a power supply area. According to the method, a vulnerability evaluation index based on a complex network theory and a risk evaluation index based on a risk theory are firstly carried out; performing weighted summation on the obtained node vulnerability indexes through an analytic hierarchy process, and determining a vulnerability comprehensive evaluation index of the power distribution network nodes based on a summation result and the risk index of each node; calculating an actual value of a vulnerability comprehensive evaluation index of the power distribution network node; based on the actual value of the vulnerability comprehensive evaluation index of the power distribution network node, determining a relatively vulnerable node in the power distribution network, namely a target node, namely a node needing vulnerability optimization, and performing targeted vulnerability optimization on the target node; according to the technical scheme, the vulnerable nodes in the power distribution network can be effectively found, the accuracy is high, the reasonability is high, and the vulnerability of the power distribution network is pointedly reduced.

This invention provides a method and system for dynamic reconfiguration and load restoration of balanced subnets. It constructs a two-stage optimization model: the first stage determines mobile resource deployment and dynamic topology connections; the second stage determines equipment power output under uncertainty. After system modeling and defining multiple types of decision variables, an objective function is constructed to maximize the difference between the total weighted restored load and the total active power loss. Three types of constraints are established: topology, equipment operation, and system safety, and the schedulable load is linearized. To address the uncertainty of renewable energy output, Wasserstein fuzzy sets are introduced to construct bibru bar chance constraints. These constraints are transformed using conditional value at risk theory, and the model is then reconstructed using strong duality theory and the stochastic saddle point theorem, transforming it into a mixed integer convex optimization problem with second-order cone constraints. This invention can efficiently achieve dynamic networking and load restoration optimization of balanced subnets while ensuring system safety.

The invention discloses a reliability modeling and risk analysis method for a numerical control machining center. The method comprises the following steps: acquiring field operation and maintenance data of the numerical control machining center and dividing the whole machine into a plurality of functional subsystems; constructing a hybrid Weibull distribution model for each subsystem, determining an optimal hybrid component number by using AIC and BIC criteria, and performing parameter estimation by using an EM algorithm to characterize life characteristics hybrid with multiple failure mechanisms; based on a competitive risk theory, calculating a cumulative fault probability CFP of each subsystem and a first fault contribution degree FFC to complete machine failure; and constructing a risk quadrant graph by taking the fault frequency and the first fault contribution degree as dimensions, evaluating the risk region category of each subsystem, and generating a differentiated maintenance strategy. According to the method, the problem that a single distribution model is difficult to adapt to heterogeneous fault data is solved, and the actual influence of the subsystem on the shutdown of the whole machine can be quantitatively evaluated, so that a scientific preventive maintenance plan is guided to be formulated.