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44 results about "Time history" patented technology

Railway station structural engineering demand parameter matrix rapid construction method and system

The invention discloses a method and a system for quickly constructing a railway station structure engineering demand parameter matrix, which are characterized in that a time-history load function, a time-history load working condition and a ground acceleration of a railway station structure model are automatically created and set through a Python programming language on the basis of an application programming interface (API) opened by MIDAS Gen design software, and the time-history load function, the time-history load working condition and the ground acceleration of the railway station structure model are automatically established and set through a Python programming language. The method comprises the following steps of: firstly, carrying out time-history analysis on a plurality of key components, then carrying out elastic-plastic time-history analysis in batches, extracting a corner of a non-elastic hinge of the key components and interlayer acceleration of the floors, and finally, automatically assembling and forming an engineering demand parameter (EDP) matrix, so that the convenience and feasibility of shock resistance toughness evaluation of the railway station are remarkably improved.
Owner:CHINA RAILWAY FIRST SURVEY & DESIGN INST GRP

High-pressure water jet ground breaking depth time history prediction method based on dynamic erosion coefficient

The invention discloses a high-pressure water jet ground breaking depth time history prediction method, and aims to solve the problem that the change of the ground breaking depth along with time cannot be accurately reflected in the prior art. The method comprises the following steps: firstly, obtaining corresponding data of ground breaking depth and time under different conditions through a jet flow ground breaking test, and further performing inversion analysis and constructing a dynamic erosion coefficient function changing along with a dimensionless stress ratio; and then the function is embedded into an ordinary differential equation representing ground breaking dynamics, and a prediction model is established. For a new construction scene, on the premise that jet flow working parameters and soil inherent attributes are known, the model is solved through numerical calculation, and a complete prediction curve that the ground breaking depth develops along with time can be simulated. According to the method, field test requirements can be remarkably reduced, a reliable basis is provided for scheme comparison and selection and parameter optimization in the early stage of construction, and accurate prediction of the ground breaking process is achieved.
Owner:JIANGXI UNIV OF SCI & TECH

Analysis method for time-history stress relaxation of anchoring force of pre-stressed anchor cable under high-pressure stress

The invention provides a method for analyzing time-history stress relaxation of anchoring force of a pre-stressed anchor cable under high-pressure stress, and relates to the technical field of geotechnical engineering. According to the method, engineering geological investigation, ground stress testing and indoor triaxial rheological testing are systematically combined, a potential high-stress area is accurately recognized, key rheological parameters of a rock-soil body are obtained, and then the stress self-adaptive creep coupling constitutive model with the long-term strength of the rock body as the criterion is constructed; and finally, accurately predicting the time-history creep strain of the rock-soil body and the anchoring force loss of the anchor cable under the high stress condition through numerical calculation. According to the method, the defect that a traditional creep theory describes a nonlinear creep behavior in a high-pressure stress state and a prestress loss coupling mechanism is effectively overcome, and the prediction precision and reliability of mechanical response of an anchoring system are remarkably improved; a basis is provided for long-term stability evaluation and safety control of prestressed anchoring engineering under complex geological conditions, and geotechnical engineering anchoring design and safety early warning are developed towards the refined and intelligent direction.
Owner:太行城乡建设集团有限公司

Load test method for beam bridge based on time history curve

ActiveCN116187116BBridge deckDesign load
The application belongs to the technical field of bridge construction, and is a beam bridge load test method based on time history curve. The method firstly carries out static load test, and then arranges test vehicles at key parts of the test bridge surface by using a step loading mode, and measures deflection points and strain points. Then, the static load test efficiency is calculated through the bridge static load test. According to the step loading mode and the static load test efficiency, a multi-working-condition bridge model is established by using a finite element method to collect time history curves. Finally, dynamic load test is carried out, control sections of each span of the bridge are selected as test sections, and strain fluctuation amplitude, impact coefficient and the like are measured through the dynamic load test. According to the test data, the stress state of the structure under dynamic load is analyzed. The application combines static load test and dynamic load test, can reflect the working performance of the bridge structure under design load, and has high reliability.
Owner:GUANGXI TRANSPORTATION SCI & TECH GRP CO LTD +1

Pipe bridge pier grading and limiting design method and device based on time history analysis method

This invention relates to the field of pipeline crossing structure safety technology in oil and gas transportation and water conservancy distribution engineering, specifically to a graded limiting design method and device for pipeline bridge supports based on time history analysis. The design method includes disc spring selection and parameter design, initial setting of graded limiting structure parameters, time history analysis verification and parameter optimization, device assembly and construction, and graded limiting layout. The supporting device includes disc spring assemblies, disc spring bases, upper pressure plates, limiting supports, and other components. The disc spring assemblies are made of stacked alloy steel, and the limiting supports have a Z-shaped structure with stiffening ribs. Each component is precision-machined and wear-resistant, and is fixed to a PTFE sliding plate with high-strength bolts. A sleeve provides sealing protection. This invention features a refined design, convenient installation, precise limiting, high stability, and flexible adjustment of the gap and disc spring combination to adapt to different pipeline bridge working conditions. It can effectively limit the lateral over-limit displacement of the pipeline bridge, avoid disc spring eccentric instability, and ensure the structural safety of the pipeline bridge under loads such as earthquakes and water hammer.
Owner:CHINA RAILWAY CONSTR BRIDGE ENG BUREAU GRP CO LTD +1

Simulation method for wind power fluctuation of prototype of hydrogen production and storage system

The invention provides a method for simulating wind power fluctuation of a prototype of a hydrogen production and storage system. The method comprises the following steps: determining a time calendar curve of generated power of a fan; scaling the time calendar curve of the generated power of the fan, and obtaining an assumed time calendar curve of the generated power of the fan according to a scaling result; determining a power change function of the developed prototype; obtaining a time calendar curve of current or voltage of the hydrogen production and storage prototype in the fluctuation simulation test according to the power change function and the assumed time calendar curve of the fan generation power; generating and testing a software instruction of the upper computer so as to finish the simulation of the fluctuation of the power supply; the method has the beneficial effects that power fluctuation simulation can be completed without an external programmable power supply through comprehensive processing by combining power data of the fan and the hydrogen production and storage prototype, and fluctuation simulation of hydrogen production and storage power not only depends on fluctuation characteristics provided by the fan, but also depends on fluctuation characteristics provided by the fan, but also depends on fluctuation characteristics provided by the hydrogen production and storage prototype. The relation that the power of hydrogen production and storage varies along with current or voltage is also considered, so that more accurate power simulation is achieved.
Owner:SHANGHAI INVESTIGATION DESIGN & RES INST CO LTD +1

Data expansion device, data expansion method, and program

This invention provides a data expansion device that can increase the amount of historical performance data when sufficient historical performance data has not been accumulated. [Solution] The data expansion device includes means for acquiring time history data relating to the operation of the equipment, means for copying the time history data to generate duplicate data, means for changing the time information included in the duplicate data, means for varying the values ​​relating to the operation of the equipment included in the duplicate data within a predetermined range, and means for merging the time history data and the duplicate data.
Owner:MITSUBISHI HEAVY IND THERMAL SYST

A recursive method for online automatic identification of seismic events

The application discloses a recursive method for online automatic identification of seismic events, which reconstructs a phase space of a time history signal of seismic motion, and then visualizes the reconstructed phase space by using a recurrence plot; the recurrence plot information is quantitatively analyzed to determine an alarm threshold when an earthquake occurs, so that the seismic event is identified according to a recurrence quantification index. Since the recurrence plot and the improved recurrence quantification index are used, the problems of non-intuitive identification result and low identification timeliness of the existing seismic event identification are solved; the recurrence plot can graphically display the seismic event, and the improved recurrence quantification index can realize real-time online early warning of the seismic event; and the method can be used for real-time monitoring and alarming of bridge seismic events, and improves the intuitiveness and identification timeliness of the identification result of the bridge seismic event.
Owner:CHANGAN UNIV

Wind speed compensation method and device based on floating wind turbine motion response and electronic equipment

The application provides a wind speed compensation method and device based on floating wind turbine motion response and electronic equipment, and the method comprises the following steps: obtaining the measured wind speed at each time in a preset time period; obtaining the motion response of the floating wind turbine in multiple preset directions of the rectangular coordinate system at each time in the preset time period according to the measured wind speed, a preset wave time history, a preset floating wind turbine numerical simulation model and a first preset formula; and compensating the measured wind speed according to the motion response and a second preset formula to obtain the compensated wind speed at each time in the preset time period. Through the application, the problem that the complex motion response of the floating wind turbine in different directions is not considered in the related art, and it is difficult to accurately compensate the measurement wind speed deviation of the laser radar erected on the top of the floating wind turbine cabin is solved.
Owner:CHINA THREE GORGES CORPORATION

Landslide state determination method based on clustering algorithm and related device

The embodiment of the application provides a landslide state determination method based on a clustering algorithm and related devices, the method comprises the following steps: obtaining displacement amounts of K monitoring points in a vertical monitoring hole of a slope within a preset time interval to obtain K time-history displacement amounts; performing clustering processing on the K monitoring points according to the K time-history displacement amounts to obtain a clustering processing result; determining M category mutation monitoring points according to the clustering processing result, wherein M is an integer less than or equal to K; and determining a landslide state of the slope according to a credibility of the M category mutation monitoring points and a number of the category mutation monitoring points. The application can determine the landslide state of the slope based on the time-history displacement amounts of the monitoring points in the vertical monitoring hole of the slope, thereby improving the efficiency of determining the landslide state of the slope.
Owner:INST OF MECHANICS CHINESE ACAD OF SCI

A small and medium-sized bridge bearing capacity evaluation method based on vehicle moving loading

The application discloses a kind of based on vehicle movement loading small and medium-sized bridge bearing capacity evaluation method, belong to bridge bearing capacity evaluation technical field, comprising the following steps: S1: time history response acquisition;S2: time history response preprocessing;S3: influence line identification;S4: bearing capacity evaluation.The application utilizes single heavy vehicle movement loading to obtain bridge time history response;Then the structural dynamic component in bridge time history response is stripped using variational mode decomposition, and then a bridge influence line identification mathematical model is constructed according to sampling frequency and vehicle wheelbase, so as to eliminate the vehicle multi-axle effect in bridge time history response;And the stable solution of bridge influence line is solved using Tikhonov regularization method;Then by carrying out virtual loading on bridge influence line, reconstructing bridge virtual static response, and using traditional check coefficient method to evaluate bridge bearing capacity, the bridge bearing capacity evaluation rate is effectively improved, and the bridge structure damage caused by high loading efficiency is avoided.
Owner:ANHUI UNIVERSITY OF ARCHITECTURE +2

Cultural relic showcase protection method and system based on active control and earthquake early warning linkage

The invention relates to a cultural relic showcase protection method and system based on active control and earthquake early warning linkage, and the method comprises the following active control stage steps: comparing real-time showcase displacement data with a vibration displacement time history curve, and obtaining a comparison result; and inputting the comparison result into a fuzzy PID module, and outputting an AMD control instruction. The method has the advantages that after seismic waves arrive, the obtained real-time showcase displacement data and the vibration displacement time history curve are compared, and the error between the vibration displacement time history curve and data obtained from the state monitoring module can be obtained. And the comparison result is dynamically adjusted through the fuzzy PID module, so that the accuracy of adjusting the AMD control instruction is improved, and the anti-seismic protection success rate of the fragile cultural relics is further improved.
Owner:INST OF GEOPHYSICS CHINA EARTHQUAKE ADMINISTRATION

Vehicle bolt loosening excitation reduction method and system based on time-related damage

The invention provides a vehicle bolt loosening excitation reduction method and system based on time-related damage, and relates to the technical field of big data processing, and the method comprises the steps: converting an original acceleration-time history of a vehicle bolt connection structure into a relative displacement-time history of vehicle bolt connection; converting the relative displacement-time history into a bolt loosening damage-time history by combining a bolt loosening D-N curve and a loosening linear accumulation model; adopting a time correlation damage editing method to edit the bolt loosening damage-time history; mapping a window marking result into an original acceleration-time history to form a reduced acceleration-time history; and calculating the key damage feature retention degree of the bolt through a bolt loosening bench test, and repeating the editing, mapping, deleting, splicing and verifying processes until the requirements are met. The method has the beneficial effects of improving the product development efficiency and the iteration speed, shortening the product development period and improving the reliability verification efficiency, and has important values.
Owner:SOUTHWEST JIAOTONG UNIV

A calculation method for the composite slope of bridge longitudinal section based on train axle load

The present application relates to a method for calculating the composite slope of a bridge longitudinal section based on train axle load, comprising: step S1, obtaining the total number of time steps for a train to cross a bridge and the position of the wheelset of the train at each time step; step S2, fitting the bridge linear function within the length of the train crossing the bridge at a certain time step; step S3, determining the slope corresponding to the axle load borne by the wheelset at the position of the wheelset on the bridge based on the position of the wheelset of the train crossing the bridge at that time step and the bridge linear function; step S4, calculating the composite slope of the train crossing the bridge at that time step based on the axle load borne by the locomotive wheelset and the axle load borne by the truck wheelset, and the slope corresponding to the axle load borne by the wheelset at the position of the wheelset on the bridge at that time step; repeating steps S2 to S4 to obtain the dynamic composite slope within the time history of the train crossing the bridge. The calculation method provided in the present application considers the influence of different slope sections and the axle load borne by the train wheelset on the slope, and the calculation results are more consistent with the actual situation and the accuracy is correspondingly improved.
Owner:CHINA RAILWAY MAJOR BRIDGE RECONNAISSANCE & DESIGN INSTITUTE CO LTD

A method and system for determining the optimal delay time of high-gas tunnel blasting cut holes

The present application relates to geotechnical engineering numerical simulation technical field, specifically to a kind of high gas tunnel blasting slot hole optimum delay time determining method and system, method includes obtaining the rock mechanics parameter of tunnel face surrounding rock and statistics explosive performance parameter;Rock mass crack propagation stage, rock mass volume increase stage and the time required for rock mass movement in rock mass throwing stage are calculated respectively, the time required for complete throwing of the rock mass to be broken;Construct the three-dimensional model of rock mass to be broken in slotting area and post-processing;Obtain the displacement and velocity time history curve of each monitoring point by numerical simulation;The time node that slotting area free surface is completely formed is judged as the optimum delay time of slot hole;According to the optimum delay time of slot hole, set slot hole delay, simulate the initiation of each row of blast hole in turn, determine the optimum initiation delay time of each row of blast hole.The present application can reveal the rock mass movement law and free surface formation timing in slotting area, and accurately design the optimum delay time of each row of blast hole.
Owner:SHANDONG UNIV OF SCI & TECH +2

A method for evaluating fatigue damage of a helicopter hub arm

The application belongs to the technical field of structure fatigue, and discloses a helicopter hub arm fatigue damage evaluation method, step one: collecting hub arm flapping bending moment Mb and oscillation bending moment Mt time history data curve of evaluation cycles; step two: determining hub arm lug force conversion structure geometric parameters; step three: calculating upper lug force and lower lug force time history curve of hub arm; step four: respectively performing rain flow counting on the upper lug force and the lower lug force time history curve, obtaining upper lug force each level alternating load and load frequency of hub arm, lower lug force each level alternating load and load frequency; step five: determining hub arm flapping bending moment fatigue limit and corresponding oscillation bending moment fatigue limit; step six: calculating fatigue life cycle number N of each level fatigue alternating load S; step seven: calculating each level damage of the upper lug, calculating each level damage of the lower lug, and calculating total damage of the upper and lower lug of the hub arm.
Owner:CHINA HELICOPTER RES & DEV INST

Method and device for conditioning seismic records in an elastic time history analysis

ActiveCN119126200BEnsemble learningSeismic signal recordingPeak ground accelerationResponse spectrum
The application relates to a method and device for selecting seismic records in elastic time-history analysis, which comprises the following steps: using effective peak ground acceleration (EPA) to adjust the amplitude of initial seismic records used in elastic time-history analysis, and screening the initial seismic records according to preset first selection parameters to obtain first seismic records; using causal inference to screen seismic parameters directly causing structure base shear, as second selection parameters; and screening the first seismic records according to the second selection parameters to obtain final seismic records used in time-history analysis. Through the method, the dispersion of final structure base shear can be well controlled, so that the results of mode decomposition response spectrum method can be corrected by using the results of elastic time-history analysis.
Owner:CITIC GENERAL INST OF ARCHITECTURAL DESIGN & RES

Proof of location and velocity blockchain consensus mechanism system and method

A system and method providing Proof of Location or Proof of Location and Velocity consensus in a blockchain network using radio frequency (RF) signals. Nodes validate the location of other nodes in the network using PING-PONG round trip signal propagation time to determine maximum distances to other nodes. These maximum distances are then shared between nodes, whereupon the nodes use computational techniques to resolve validated, geospatial location of the other nodes. The sharing of measured maximum distances to local nodes is a form of Proof of Location consensus. The validated geospatial locations (and velocities) of local nodes are then written to the blockchain, creating a time history for each node. This information may be used by the blockchain operating rules to implement any number of security and other operational functions. The ability of the invention to operate without need for time synchronization between nodes is an advantage of the system.
Owner:SPACE TELECOMMUNICATIONS INC

Offshore wind turbine time-varying reliability dynamic evaluation method, device, equipment and medium

The invention discloses an offshore wind turbine time-varying reliability dynamic evaluation method, device and equipment and a medium, and the method comprises the steps: obtaining offshore wind turbine multi-source heterogeneous monitoring data, and carrying out the edge preprocessing; the method comprises the following steps: establishing a depth operator network agent model according to offshore wind turbine multi-source heterogeneous monitoring data, and performing offline training to obtain initial model parameters; according to the predicted tower top displacement, the basic inclination angle time history and the measured value, calculating an output residual error of a depth operator network agent model, and constructing an adaptive asynchronous weighted likelihood function framework; the method comprises the following steps: establishing a Bayesian asynchronous sequential updating mechanism by combining a self-adaptive asynchronous weighted likelihood function framework on the basis of arrival time difference of monitoring data of an offshore wind turbine multi-source asynchronous monitoring system; and based on the model parameters updated by the Bayesian asynchronous sequential updating mechanism, executing failure probability threshold judgment and time-varying reliability dynamic evaluation. The problems of real-time early warning and intelligent operation and maintenance decision making of the safety state of the fan structure in the complex marine environment are solved.
Owner:SUN YAT SEN UNIV

Man-machine interactive method and apparatus for long-endurance operation based on dynamic time pressure

The present disclosure provides a man-machine interactive method and apparatus for a long-endurance operation based on a dynamic time pressure, belonging to the technical field of man-machine ergonomics. The method specifically includes: constructing a maximum performance-time pressure-time function curve based on a performance-time pressure function curve corresponding to a long-endurance operation; calculating a response time of a next long-endurance operation based on a historical response time of man-machine interaction after the current long-endurance operation is completed; calculating a maximum performance value corresponding to an initial time of the next long-endurance operation and a time pressure corresponding to the maximum performance value based on the maximum performance-time pressure-time function curve; and calculating an optimal reserved time corresponding to the maximum performance value based on the response time of the next long-endurance operation and the time pressure. The method and the apparatus can improve the performance level of the man-machine interaction during the long-endurance operation, and reduce human errors caused by cumulative fatigue and too short reserved time of the operation, thereby improving the flight safety.
Owner:ZHEJIANG LAB

Method for determining time lag of double-cylinder wake flow induced vibration

The invention discloses a time lag determination method for double-cylinder wake flow induced vibration, and belongs to the technical field of fluid mechanics and structural vibration. The method effectively solves the fundamental problem that a traditional theoretical model cannot predict wake flow-induced vibration due to neglect of a time-delay effect. According to the method, the vibration amplitude is taken as the reference, the optimal time lag parameter is inverted through two rounds of search, then the function relation between time lag and non-dimensional variables such as the interval ratio and the converted wind speed is built, and finally a prediction model capable of accurately reflecting wake flow induced vibration response characteristics is built. The corrected quasi-steady theoretical model can accurately reproduce the actual response of the wake flow induced vibration area, and the breakthrough from'unpredictable 'to'accurate prediction' is realized. The model not only can accurately reproduce a vibration response curve, a phase relation and dominant frequency characteristics, but also has excellent performance in the aspect of aerodynamic reconstruction, and lift and resistance time travel curves obtained through test acquisition and theoretical calculation have high consistency.
Owner:HARBIN INST OF TECH

A method, device, medium and product for reconstructing and locating a time history of an impact load

ActiveCN119830433BAccurately identify timeAccurately identify locationGeometric CADData setDistance matrix
The application discloses a shock load time history reconstruction and positioning method, device, medium and product, relates to the field of shock load identification, and comprises the following steps: acquiring an acceleration signal matrix and a dynamic graph structure of a shock load acting object; according to the acceleration signal matrix and the dynamic graph structure, a time history reconstruction model is used to obtain a reconstructed shock load time history of the shock load acting object; the time history reconstruction model is obtained by training a graph neural network model by using a first training data set and a dynamic graph structure of a shock load acting object for training; according to an encoding distance matrix of the acceleration signal matrix, a shock positioning model is used to determine the shock position of the shock load acting object; and the shock positioning model is obtained by training a fully-connected neural network by using a second training data set. The application can accurately identify the shock load time history and the shock position when the load acting position is unknown.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Single-stage evaluation of an axle counter time history

PendingDE102024204664A1Vehicle route interaction devicesTime courseData set
A procedure for evaluating a data set (110) is described, comprising the following procedure: i) Recording a one-dimensional time history as a data set (110) using an axis counter (100); and ii) Evaluating the data set (110) by identifying signals in the one-dimensional time course and classifying the signals in the one-dimensional time course in one step using a one-step deep learning-based algorithm (150).
Owner:SIEMENS MOBILITY GMBH

Incremental dynamic correction method for related spectrum duration evolution of gravity dam

The invention relates to the technical field of seismology, in particular to an incremental dynamic correction method for related spectrum duration evolution of a gravity dam, which comprises the following steps: establishing a finite element model of the gravity dam, determining mechanical parameters, nonlinear behaviors and boundary conditions of the model, and setting analysis working conditions; based on the seismic characteristics of a specific site, determining the coupling evolution law of the seismic oscillation duration and the seismic oscillation spectrum shape along with the seismic intensity; non-linear responses of the gravity dam under different analysis working conditions are obtained, and the non-linear response difference between the standard IDA working condition and the actual coupling working condition and only one of the working conditions changing along with the peak ground acceleration is determined; and constructing a unified correction model, and correcting an analysis result of a standard IDA method by quantifying a spectrum form difference and a duration difference and introducing a spectrum shape effect function, a duration correction coefficient and a coupling correction coefficient so as to eliminate systematic deviation.
Owner:TAIYUAN UNIVERSITY OF TECHNOLOGY

Bridge time history prediction method, device, equipment and computer program product

The invention belongs to the field of data processing, and provides a bridge time history prediction method, device and equipment and a computer program product. According to the embodiment of the invention, dynamic characteristic data such as wind speed, wave height and seismic oscillation of the target bridge and static characteristic data such as material strength and damping ratio of the target bridge are obtained and input into the pre-trained bridge response prediction model for processing, and the time-history response data of the target bridge is obtained and output, so that the method can adapt to bridge structure parameter changes, and the accuracy of bridge structure parameters is improved. The dynamic response of the bridge under the multi-source load coupling effect in a complex environment is predicted, and the time history prediction precision of the bridge is improved.
Owner:TSINGHUA SHENZHEN INTERNATIONAL GRADUATE SCHOOL

Method and system for seamless long-term cyclic temperature load pattern formation applicable to time history analysis

The application provides a seamless line long-term cyclic temperature load mode forming method and system applicable to time history analysis, belongs to the technical field of railway seamless line operation and maintenance, determines a seamless line work point position, and obtains local environmental temperature data; an empirical wavelet decomposition algorithm is used to separate annual cycle signals and daily cycle signals of the environmental temperature; annual temperature components of the cyclic load are obtained through formula fitting; daily extreme temperature curves of the rail temperature are obtained; daily temperature components are calculated according to the geographical position and in combination with daily extreme temperature characteristics; the annual temperature components and the daily temperature components are superimposed to form complete long-term cyclic temperature loads. The application can calculate the temperature load according to meteorological data and in combination with the seamless line design specification, so that the long-term cyclic temperature load mode has good universality; time-frequency analysis methods are used to extract and analyze the time characteristics of the seamless line temperature data, which can provide a reference basis for the design of the long-term cyclic temperature load of the seamless line.
Owner:BEIJING JIAOTONG UNIV +3

Fan tower barrel service life monitoring method and storage medium

The invention discloses a fan tower life monitoring method and a storage medium. The method comprises the steps of generating displacement time history data through an acceleration signal, combining a dynamically corrected stress amplitude calculation model, matching an S-N curve to determine a single damage ratio, performing classification statistics on annual accumulated damage values according to working conditions, and triggering hierarchical risk control based on a residual life index. According to the method, the problems of poor environmental adaptability, inaccurate damage quantification and risk response lag in a traditional method are solved, and the safety of the tower drum in the whole life cycle is remarkably improved.
Owner:YUNNAN HUADIAN FUXIN ENERGY POWER GENERATION CO LTD +2

A multi-degree-of-freedom random vibration test condition calculation method

ActiveCN115758043BAlgorithmRandom vibration
The application provides a multi-degree-of-freedom random vibration test condition calculation method, and belongs to the technical field of vibration environment test, and comprises the following steps: S1, determining a task scene and a life period event; S2, establishing a multi-degree-of-freedom random vibration time history sample; S3, statistically summarizing a multi-degree-of-freedom random vibration power spectral density matrix to obtain maximum expected SDMs of all events in the task scene; S4, calculating the maximum expected SDMs of all events to synthesize a random vibration environment and obtaining a final synthesized SDM; S5, normalizing the power spectral density matrix; S6, testing the test condition calculation result to verify that the test condition calculation result can envelope measured data. Compared with a traditional multi-degree-of-freedom test condition calculation method, the application avoids the problem of being too conservative, solves the problem of matrix non-positive definiteness through positive definiteness checking and corresponding modification in a key step, and improves the fine level of test condition preparation.
Owner:BEIJING INST OF STRUCTURE & ENVIRONMENT ENG

A baseline correction method applicable to fault ground motion

ActiveCN120722434BSeismic signal processingComputational physicsCrossover frequency
This invention provides a baseline correction method applicable to fault ground motion, comprising the following steps: inputting the earthquake acceleration time history to be corrected and the corresponding GPS measured displacement data; randomly generating an initial population containing time parameters t1 (start time of the strong earthquake segment) and t2 (start time of the last segment of the velocity time history); performing baseline correction on each individual in the population: obtaining the velocity time history by subtracting the mean of the pre-earthquake acceleration based on t1 and integrating; obtaining the displacement time history by fitting the linear trend of the last segment of the velocity based on t2, subtracting the fitted acceleration component, and then integrating twice; using the absolute value of the residual between the corrected displacement end value and the GPS data as the objective function; updating the population through a differential evolution algorithm, wherein the mutation factor and crossover frequency can be dynamically adjusted according to the ground motion velocity time history, displacement residual, and number of iterations to balance global and local searches and avoid invalid solutions; iteratively optimizing until the residual is less than a threshold or the maximum number of iterations is reached; finally outputting the optimal t1, t2, and the corrected displacement time history.
Owner:FUZHOU UNIV

Method for identifying maximum position of temperature change rate in start-stop and peak regulation of steam turbine rotor

The invention belongs to the technical field of turbine rotor fatigue life prediction, and particularly relates to a turbine rotor maximum temperature change rate position identification method in start-stop and peak regulation, which is characterized by comprising geometric modeling, temperature field calculation, monitoring point selection, temperature time history data extraction, change calculation and time derivation. The method has the beneficial effects that the judgment is performed based on the result of the IMT criterion, and the identification of the position with the maximum temperature change rate in the start-stop and peak regulation conditions in the running process of the steam turbine rotor is realized by comparing the trend of the IMT result of the alternative monitoring point; through comparison of temperature fluctuation results under different operation conditions, recognition of the maximum temperature fluctuation point is finally obtained, the damage condition of the rotor is found in advance, and catastrophic accidents are avoided. The method is suitable for quantitative evaluation of the maximum temperature fluctuation point of the steam turbine rotor, and effectiveness and feasibility of the criterion in identification of the maximum temperature fluctuation point of the steam turbine rotor are verified through case research.
Owner:SHENYANG AGRI UNIV