15 results about "Stress range" patented technology

In the present disclosure, an electronic device may comprise: at least one sensor; a memory including one or more storage media storing instructions; and at least one processor including a processing circuit. The instructions may, when individually or collectively executed by the at least one processor, cause the electronic device to perform at least one operation. The at least one operation may comprise an operation of acquiring a biometric signal by using the at least one sensor. The at least one operation may comprise an operation of identifying a stress level at least partially on the basis of the acquired biometric signal. The at least one operation may comprise an operation of determining a conversation topic at least partially on the basis of the identified stress level satisfying a specific stress range. The at least one operation may comprise an operation of outputting a plurality of messages corresponding to the determined conversation topic as at least a part of an interactive conversation with a user through a specific application.

The invention discloses a spherical shell enveloping type space connection structure for an X-shaped steel pipe joint, which is characterized in that an eccentric spherical shell enveloping body with continuous three-dimensional curvature is arranged on the outer side of a penetrating area of a main pipe section and an inclined strut section, and adopts a thickness control function based on a spherical angle, so that a shell forms directional enhancement in an inclined strut stress direction; and continuously and gradually changing in other directions so as to obtain smooth local rigidity distribution. Through the spherical shell force flow diffusion correction function, the node equivalent bending moment and the equivalent membrane force expression, a calculation model of the stress range of node hot spot stress, stress gradient, fatigue and the like can be established, and accurate representation of node stress behaviors is achieved. According to the joint structure, the hot spot stress of the intersecting area of the inclined strut and the main pipe can be remarkably reduced, the diffusivity of force flow on the shell is improved, the local stress gradient of the joint is improved, and therefore the fatigue life of the X-shaped joint of the offshore wind power jacket is prolonged, the overall structure safety is improved, and the joint structure is suitable for engineering application of steel pipe joints of various scales.

The invention relates to a steel bridge deck pavement sensing analysis system and method based on multi-dimensional data. The method comprises the following steps: testing raw materials to obtain construction retention time and interface parameters so as to guide mixture design, preparing a test piece according to the construction retention time and the interface parameters, and measuring a dynamic modulus main curve, a fatigue damage model and limit strain; establishing a reduced-scale test piece finite element model based on the main curve to predict bending-tensile strain, and performing a fatigue test in combination with limit strain to obtain reduced-scale life; obtaining a key stress range of the steel plate through full-scale model finite element analysis, and formulating an acceleration loading scheme according to the key stress range; loading is executed, multi-source monitoring data are collected, and the full-scale final fatigue life is determined; calibrating a fatigue damage model according to the service life; and finally evaluating the performance of the paving system based on the calibration model, the main curve and the full-scale life. According to the closed-loop verification process from the material to the full scale, the prediction model is iteratively calibrated through multi-scale test data, and the accuracy and reliability of long-term performance evaluation of the steel bridge deck pavement system are remarkably improved.

The invention provides a large-span water conservancy gate design method and a large-span water conservancy gate The large-span water conservancy gate design method comprises the steps that S1, a model of a supporting beam is obtained according to design parameters and the steel using amount of the supporting beam; s2, calculating the actual stress of each part of the support beam according to the model, comparing the actual stress with the allowable stress of the support beam, and judging whether the steel consumption of the support beam needs to be adjusted or not according to the comparison result of the actual stress and the allowable stress; and S3, when it is judged that the steel using amount of the supporting beam needs to be adjusted, the steel using amount of the supporting beam is adjusted, and the step S1 and the step S2 are repeated till the actual stress is within the allowable stress range. The problem that in the prior art, the steel using amount of a large-span water conservancy gate is not reasonable is solved.

This application discloses a method and related equipment for determining the stress range distribution of a structure. By optimizing the frequency domain discretization and time domain reconstruction methods, combined with multi-round statistical optimization and fusion strategies, a stable and reliable structural stress range distribution is output. The method includes: acquiring the stress power spectrum of the target structure, randomly dividing frequency intervals within a preset frequency band and assigning phases to obtain a discrete spectrum; reconstructing the time domain stress history and counting rainflow to generate multiple sets of dimensionless rainflow stress range probability density distributions; after average smoothing and moment preservation correction, using a multi-smoothing strategy to generate candidate sub-distributions, and combining them with evaluation indicators for weighted fusion to obtain the final distribution. This application improves the realism of the time history through random discretization, achieves distribution convergence through multiple statistical fusions, and balances smoothness and statistical characteristics through moment preservation and multi-strategy fusion. Only the stress power spectrum is required as input, making it suitable for complex scenarios such as broadband and multi-peak spectra. It can be embedded into existing systems for automated operation, reducing analysis costs and improving fatigue assessment accuracy.

The invention discloses a fatigue test method, device and system for a welding seam of a T-shaped joint, and the method comprises the steps: building a quantitative relation between a loading load acting on the free end of a web plate and the stress at a weld toe according to the geometric dimension of a T-shaped joint sample; according to the stress ratio specified by the fatigue test and the stress range at the weld toe, the average loading load and the load amplitude are calculated based on the quantitative relation; fixedly connecting the T-shaped joint weld fatigue test device to a fatigue testing machine, and fixedly connecting the T-shaped joint sample to the working surface of the T-shaped joint weld fatigue test device; and setting load parameters as the average loading load and the load amplitude in a fatigue testing machine, applying an alternating load to the free end of the web of the T-shaped joint sample to carry out a fatigue test, and recording the cycle index when the weld joint of the T-shaped joint sample is in fatigue failure. According to the invention, the test detection of the fatigue life of the welding seam of the T-shaped joint can be realized, and the obtained fatigue life provides support for optimization of a welding structure and a welding process of engineering machinery.

The invention discloses a method for evaluating the vibration fatigue life of a liquid-filled composite rocket storage tank. Liquid oxygen is taken as an example. The method comprises the following steps: firstly, establishing a finite element analysis model through an acoustic-structural coupling method; then calculating modal stress of each order of modal of the model through modal analysis, and calculating a frequency response function of each order of modal of the model through frequency response analysis; constructing a stress range probability density function of the model in combination with a random vibration method; and then, according to a linear cumulative damage criterion and S-N curve data of the material, establishing a random vibration fatigue life prediction model of the storage tank. The model fuses S-N curve data under equivalent zero average stress, and considers the layering details of the composite material in the modeling stage of the storage tank, so that the random vibration fatigue life of the storage tank can be predicted more comprehensively and accurately.

The invention belongs to the technical field of medical instruments, and discloses an operation fixing retractor capable of observing the stress range, the operation fixing retractor comprises a retracting hook and a retracting structure used for fixing the retracting hook, the retracting hook comprises a stretching belt and a drag hook arranged at the end of the stretching belt, and the stretching belt is of a chain bead structure formed by sequentially and alternately connecting a plurality of connecting pieces and elastic pieces end to end; each connecting piece is provided with an observation window, each elastic piece is formed by sleeving a plurality of layers of relatively independent elastic units, the two ends of each elastic unit are respectively provided with a head end and a tail end, the head ends and the tail ends of all the elastic units of each elastic piece are respectively clamped in the adjacent connecting pieces, and gaps exist between the end parts of the elastic units in a free state. When the retracting hook is stressed and stretched to be clamped on the retracting structure, the gaps between the ends of the elastic units of the elastic piece participating in stretching are gradually reduced till the elastic units are tightly attached, and when the retracting hook is stressed and stretched, the stress range of the retracting hook is determined through the number of the elastic units with the ends tightly attached together observed through the observation window of the connecting piece when the retracting hook is stressed and stretched.

Provided in the present invention is a fatigue criterion and data-driven integrated method for gear fatigue pitting life prediction. The method comprises: collecting gear contact fatigue data of different materials from published literature, so as to construct an original data set; on the basis of gear parameters and engagement conditions in the literature, using ABAQUS simulation software to establish a two-dimensional finite element model of a local spur gear; using precise stress and strain results obtained by means of simulation to perform life calculation and verification in combination with an FS method; calculating pitting life within an experimental contact stress range by means of changing loads and using the FS method, so as to expand the original data set; applying a generative adversarial network model to further expand the data set; and finally, on the basis of the recombined data set, establishing a graph convolutional network model to perform fatigue pitting life prediction. The present method exhibits higher accuracy in prediction results. The implementation of the method provides an effective solution for small-sample failure analysis of a gear transmission system, thereby demonstrating engineering application value.

The invention relates to a marine riser bottom goose neck local scour depth and fatigue damage prediction method, and belongs to the technical field of ocean engineering. The method comprises the following steps: carrying out hydrodynamic analysis on a goose neck part at the bottom of the marine riser to obtain a pipe surface pressure time history, a shear stress time history and a seabed bottom shear force; calculating sediment movement by combining a suspended load and bed load sediment transport model to obtain real-time change of bed surface elevation and local dynamic scouring depth; fusing the pressure time history and the shear stress time history of the pipe surface to obtain a fusion load vector; carrying out structural dynamics coupling analysis on the basis of the vector, synchronously updating a time-varying stiffness matrix, and solving a structural motion equation through a Newmark-beta method to obtain a fatigue hotspot node stress time history; processing through a rain flow counting method to obtain a stress range spectrum; and calculating the total fatigue damage and predicting the fatigue life by combining a marine environment S-N curve and a Miner linear cumulative damage rule. The accuracy of fatigue life prediction can be improved.

The utility model relates to the technical field of hoisting suspension sling, especially to a kind of sling for hoisting suspension, it include: main sling, side sling is set in the side of the main sling, the side sling is symmetrically provided with two groups of limit rod in the side close to the main sling.The utility model converts the originally single stress point into two stress points by the design of main sling and side sling, and the distance between main sling and side sling can be adjusted by cooperating with limit rod, and then the stress range of lifting is enlarged.When goods and air sway, stress will first cause the bottom hook cable to sway, and then transmit to the place of main sling and side sling, because the distance between main sling and side sling is widened, the stress range is enlarged, and the force generated by swaying in this series of processes will be gradually reduced, so the force of swaying cannot affect the initial top sling of hoisting equipment at this time.

The application relates to a method for predicting local scouring depth and fatigue damage of a marine riser bottom goose neck, and belongs to the technical field of ocean engineering. The method comprises the following steps: performing fluid dynamics analysis on the local goose neck of the marine riser bottom to obtain pipe surface pressure time history, shear stress time history and seabed bottom shear force; combining the suspended load and the sediment transport model to calculate sediment movement, and obtaining real-time changes of the bed elevation and the local dynamic scouring depth; fusing the pressure time history and the shear stress time history of the pipe surface to obtain a fused load vector; performing structure dynamics coupling analysis based on the vector, synchronously updating a time-varying stiffness matrix, solving a structure motion equation through a Newmark-beta method, and obtaining a fatigue hot spot node stress time history; processing the stress range spectrum through a rain flow counting method; combining an ocean environment S-N curve and a Miner linear cumulative damage rule to calculate total fatigue damage and predict fatigue life. The application can improve the accuracy of fatigue life prediction.

The present application belongs to the technical field of fatigue fracture quantitative analysis, and relates to a single crystal high-temperature alloy low-cycle fatigue expansion stress fracture quantitative backstepping method based on fatigue strip features. First, the low-cycle fatigue test of a sample is carried out, and the change of stress data is monitored during the fatigue test process. Through fracture feature analysis, the fatigue initiation and expansion stages are divided. The fatigue expansion life fracture quantitative backstepping of the modeling sample is based on the modeling of the fatigue strip spacing. The fatigue total life corresponding to different crack lengths of the modeling sample is analyzed. The stress range corresponding to different crack lengths of the modeling sample is determined. The low-cycle fatigue expansion stress fracture quantitative backstepping model is established. The low-cycle fatigue expansion stress fracture quantitative analysis model is applied. The method solves the problem that the direct use of the stress intensity factor range K to characterize the low-cycle fatigue fracture feature may not be suitable or have a large error, and provides an effective new method for realizing the low-cycle fatigue fracture quantitative backstepping of the fatigue expansion stress.

The invention discloses a welding structure fatigue damage prediction method and system based on a modal shape, and belongs to the field of mechanical structure welding fatigue prediction. The method comprises the steps that a finite element model of a key welding part is established, a unit and node subset on a welding seam local model is selected, and modal node force and modal node torque in a preset order are output through frequency analysis; on the basis of a structural stress method, modal structural stress is calculated, and the modal structural stress is converted into modal equivalent structural stress according to the ASME standard; applying unit loads to different load points to perform kinetic analysis, outputting frequency response functions, and splicing the frequency response functions to form a frequency response function matrix; on the basis of a spectral analysis principle, the modal coordinate cross-spectral density is calculated; calculating the stress self-spectrum density of the equivalent structure based on a modal superposition principle; based on a Dirlik method, a probability density function of an equivalent structure stress range is constructed through the equivalent structure stress self-spectral density; and fatigue damage is calculated based on a main S-N curve method.

The invention discloses a calculation method and system for a fatigue creep interaction coupling damage factor of a material, and belongs to the technical field of material mechanical property testing and service life prediction. The method comprises the following steps: acquiring a unit time alternating fatigue damage factor of a material under stress amplitudes of a fixed maximum stress and a fixed minimum stress; acquiring unit time creep damage factors of the material under different constant load holding stresses in a preset stress range; acquiring the fatigue creep interaction fracture life of the material under the load holding time; and based on the fatigue creep interaction fracture life, the unit time alternating fatigue damage factor and the unit time creep damage factor, calculating the fatigue creep interaction coupling damage factor of the material. According to the method, the coupling damage factor is obtained, and the nonlinear mutual promotion effect between the fatigue load and the creep holding load is quantified by using the coupling damage factor, so that the limitation of the traditional linear cumulative damage theory is broken through, and the problem that the coupling damage is difficult to quantify in the prior art is solved.