12 results about "Relaxation curve" patented technology

The embodiment of the invention provides an epoxy molding compound testing method and system based on production state monitoring, and belongs to the technical field of material mechanics detection. The method comprises the steps that whether sampling is triggered or not is judged based on a state vector S; feeding the powder sample into a micro cylinder test cavity; performing isothermal locking on the powder sample in the micro cylinder test cavity to obtain a corresponding force-displacement curve, a dead load relaxation curve and an unloading recovery curve; and determining a corresponding mechanical property index based on a force-displacement curve, a dead load relaxation curve and an unloading recovery curve, and combining the mechanical property index with the state vector S to execute threshold adaptive regression so as to generate a detection result of the current batch of epoxy molding compound. According to the scheme, the production state monitoring data and the mechanical test result are combined, so that the accurate judgment of the batch quality of the epoxy molding compound and the self-adaptive optimization of the process parameters are realized.

This invention discloses a method and system for testing rock pore size distribution curves based on nuclear magnetic resonance (NMR) technology. The method includes: preprocessing the rock sample to be tested and obtaining the porosity and transverse relaxation time curves of the sample at room temperature and low temperature; obtaining the measured value of unfrozen water content by the ratio of low-temperature to room-temperature porosity, serving as an objective benchmark for verifying theoretical results; converting the room-temperature relaxation curve into a cumulative pore size distribution curve, fitting and extracting pore characteristic parameters, and substituting relevant characteristic parameters into a theoretical model to calculate the theoretical value of unfrozen water content; iteratively optimizing the transverse surface relaxation rate to ensure the deviation between the theoretical and measured values ​​meets accuracy requirements; establishing a precise correspondence between relaxation time and pore radius; and outputting the final pore size distribution curve. Each step is interconnected and mutually supportive, forming a complete logical closed loop. This provides reliable technical support for characterizing rock pore structure.

The application provides an intelligent charging and discharging management system and method for a lithium battery module, and relates to the technical field of battery charging and discharging management. After detecting a charging connection signal, a relaxation curve of a cell terminal voltage decay over time is collected and fitted to determine a polarization voltage amplitude and a polarization relaxation time constant at the current time; according to the current state of charge, the target state of charge and the maximum allowable charging rate, the theoretical shortest charging time, the waitable time and the latest starting time are calculated; according to the waitable time, the current temperature of the lithium battery module and the current cycle number of the lithium battery module, the highest tolerable polarization voltage value is determined; the waitable time is taken as the upper limit of the time budget, and the polarization voltage amplitude is not greater than the highest tolerable polarization voltage value as a necessary condition, and the earliest time that meets the necessary condition in the time interval from the current time to the latest starting time is taken as the best charging starting time. The charging efficiency of the lithium battery module is improved.

The present application relates to a kind of cardiac magnetic resonance longitudinal relaxation time measurement method, medium and equipment.The measurement method includes the following steps: S1 uses MOLLI sequence respectively before and after scanning contrast;Specifically, in the before and after scanning contrast, by setting different initial inversion time TI, setting 3 groups of LL experiment LL1, LL2, LL3 triggered by continuous ECG, enough relaxation curve sampling points are obtained after fusion;And data is collected at the end of diastole of cardiac cycle, and 1 image is obtained per heartbeat;S2 image processing.This measurement method can realize single-pixel high-resolution T1 mapping under the breath holding of selection data acquisition and multi-LL experiment data fusion, give consideration to high accuracy, high resolution and high efficiency, and have good compatibility and practicality, provide new scheme for early diagnosis of heart disease, lesion quantification and prognosis evaluation, have wide clinical application prospect.

A detection method for detecting a detection target magnetic particle using an alternating excitation magnetic field includes: a step (S1) of acquiring, for a candidate magnetic particle, a Néel relaxation curve representing a relationship between a Néel relaxation time and a particle diameter; a step (S2) of acquiring, for the candidate magnetic particle, a Brownian relaxation curve representing a relationship between a Brownian relaxation time and the particle diameter; a step (S3) of determining, as an intersection point particle diameter, a particle diameter corresponding to an intersection point of the Néel relaxation curve and the Brownian relaxation curve; and a step (S4) of selecting, as the detection target magnetic particle, the candidate magnetic particle having a particle diameter larger than the intersection point particle diameter.

This invention provides a testing method and system for epoxy molding compounds based on production status monitoring, belonging to the field of materials mechanics testing technology. The method includes: determining whether sampling is triggered based on a state vector S; sending a powder sample into a micro-cylinder testing chamber; isothermally locking the powder sample in the micro-cylinder testing chamber to obtain corresponding force-displacement curves, constant load relaxation curves, and unloading recovery curves; determining corresponding mechanical property indicators based on the force-displacement curves, constant load relaxation curves, and unloading recovery curves; and combining the mechanical property indicators with the state vector S to perform threshold adaptive regression to generate the test results for the current batch of epoxy molding compounds. This invention combines production status monitoring data with mechanical testing results to achieve accurate batch quality determination and adaptive optimization of process parameters for epoxy molding compounds.

This application relates to the field of power battery status and safety diagnostic technology, and particularly to a method, device, and vehicle for diagnosing power batteries. The method includes: acquiring current static data of the power battery; generating a current voltage relaxation curve based on the current static data; extracting multi-dimensional feature parameters from the current voltage relaxation curve; calling a diagnostic model for the power battery, wherein the diagnostic model has a first mapping relationship and a second mapping relationship, wherein the first mapping relationship is a mapping relationship between multiple feature parameters and predicted health status, and the second mapping relationship is a mapping relationship between multiple feature parameters and predicted lithium plating probability; inputting the multi-dimensional feature parameters into the diagnostic model, and determining the predicted health status and predicted lithium plating probability of the power battery through the diagnostic model. This solves the problem that the diagnosis of power batteries in related technologies is relatively simple and has poor diagnostic coverage.

The invention relates to the technical field of polymer packaging material viscoelasticity constitutive model testing, in particular to an improved polymer packaging material viscoelasticity constitutive model testing and fitting method.The method includes the steps that an actual stress relaxation curve and a main curve are subjected to overlapping mean value re-fitting, and the shape and parameters of the main curve are optimized; replacing the energy storage modulus translation amount with the relaxation modulus translation amount to optimize a shift factor; an interpolation method is adopted to replace a WLF equation in numerical calculation, so that the input precision is improved; sample errors and human experience errors are reduced from multiple links of testing, fitting and numerical calculation, and fitting deviation of a WLF equation is eliminated, so that the model keeps high precision in a wider temperature range, and closed-loop verification of viscoelasticity testing is realized; a high-precision material test engineering scheme is provided for advanced electronic packaging, the production loss is reduced, the prediction capacity for packaging signals, heat transfer and stress is remarkably improved, the product yield is increased, the service life is prolonged, and the long-term reliability is improved.

The invention relates to a rock material mechanical property testing technology, in particular to a rock-like material uniaxial compression relaxation stress threshold value testing method and device, which adopts a multi-stage stress loading and single sample continuous testing mode, and adopts fixed short-time observation in combination with an objectively determined stress relaxation rate threshold value criterion to test the rock-like material uniaxial compression relaxation stress threshold value. The rock-like material uniaxial compression relaxation stress threshold value is rapidly and accurately measured, the test period of a traditional complete relaxation curve measuring method is remarkably shortened, and meanwhile the reliability and repeatability of a test result are kept.

The invention discloses a Na-23 density adaptive multi-echo pulse sequence design and use method, the Na-23 density adaptive multi-echo pulse sequence is designed and subjected to nuclear magnetic resonance scanning, sampling data obtaining, image reconstruction and T2 * relaxation curve fitting, the Na-23 density adaptive multi-echo pulse sequence sequentially comprises a plurality of multi-echo pulse subsequences, and the multiple multi-echo pulse subsequences sequentially comprise a plurality of multi-echo pulse subsequences; each multi-echo pulse sub-sequence sequentially comprises a Na-23 excitation pulse and a plurality of echo units, and each echo unit comprises components of coding gradients in three axial directions which are synchronously opened; the collection of Na-23 signals is completed in the whole k space corresponding to each echo unit; and the coding gradient sequentially comprises a density self-adaptive coding gradient unit and a gradient compensation unit. According to the method, motion artifacts and background noise can be dispersed, and the signal-to-noise ratio (SNR) is improved; aliasing artifacts are reduced; the image resolution is improved; and a T2 * relaxation curve can be fitted more finely.

The application discloses a density self-adaptive multi-echo pulse sequence design and use method of Na-23, designs a Na-23 density self-adaptive multi-echo pulse sequence, and performs nuclear magnetic resonance scanning, obtains sampling data, image reconstruction and T2* relaxation curve fitting, and the Na-23 density self-adaptive multi-echo pulse sequence comprises a plurality of multi-echo pulse sub-sequences in sequence, each multi-echo pulse sub-sequence comprises a Na-23 excitation pulse and a return unit in sequence, each return unit comprises components of three axis direction encoding gradients which are synchronously turned on; the signal of Na-23 is collected in the whole k space corresponding to each return unit; and the encoding gradient comprises a density self-adaptive encoding gradient unit and a gradient compensation unit in sequence. The application can disperse motion artifacts and background noise, improve the signal-to-noise ratio SNR, reduce aliasing artifacts, improve image resolution and finely fit the T2* relaxation curve.

The invention relates to the technical field of battery state evaluation, and discloses an SOC differentiated state evaluation method for an energy storage module, which comprises the following steps: applying symmetric electrical excitation pulses with equal electric quantity and opposite polarities to a battery module, and respectively obtaining a first voltage relaxation curve and a second voltage relaxation curve after the symmetric electrical excitation pulses; furthermore, a differentiation index for directly quantifying the internal unbalance degree is generated by calculating and integrating the asymmetric response between the two curves, and an instant symmetric electrical disturbance reference system is constructed in the battery module, so that the internal unbalance degree can be directly quantified under the condition of not depending on any historical baseline data or external compensation model. According to the method, the asymmetric state information of the battery is directly extracted from the internal contrast relation generated by one-time detection action, the evaluation result avoids the influence of common drift introduced by factors such as environment temperature change and uniform aging, and a basis is provided for distinguishing unbalanced physical sources.