31 results about "Stress assessment" patented technology

The present invention relates to a shale gas reservoir crustal stress logging prediction method based on a rock physics model. According to the method, a shale gas reservoir rock physics model which takes kerogen particles into consideration is established, so as to predict a longitudinal and transverse wave velocity of the logging; based on the above, a maximum and minimum horizontal principal stress and a fracture pressure of the reservoir are calculated; and an accurate stress assessment of a shale gas reservoir is carried out while a transverse wave logging is not provided. The beneficial effects of the invention are that: the rock physics model in line with characteristics of the shale gas reservoir is established to improve precision of the prediction velocity; and based on the rock physical model, the maximum and minimum horizontal principal stress and the fracture pressure are obtained, so that while the measured transverse wave logging data are not provided, the underground stress can be predicted on the basis of a conventional logging curve, and the prediction result is high in accuracy.

The invention discloses a falling-down detection device and method. A gyroscope, an accelerometer and a magnetometer are respectively used for measuring to obtain angular speed data, accelerated speed data and terrestrial magnetism data; the angular speed data are utilized to solve a basic posture angle, and the accelerated speed data and the terrestrial magnetism data are utilized to carry out noise self-adapted Kalman fusion filtering on the basic posture angle to obtain a final posture angle. The angular speed data and the accelerated speed data are used tor carrying out movable and static state judgment on a user; when the user is static, whether the user lies down or not is judged according to the posture angle; if the user lies down, conscious/unconscious screening and falling-down stress assessment of lying-down movement is carried out to judge whether the user falls down or not in a combined manner; when the user falls down, an alarm is sent out. According to the falling-down detection device and method disclosed by the invention, the obtained posture angle is more accurate than that obtained by using a common method; meanwhile, the conscious/unconscious screening and the falling-down stress assessment are used for carrying out combined judgment so that a falling-down judging result is accurate and the false alarm rate is reduced.

The invention discloses a winding stress assessment method based on a three-dimensional electromagnetic coupling model of a transformer. The method is characterized by comprising: establishing the three-dimensional electromagnetic coupling model of the transformer and solving the model; calculating a leakage magnetic field of the transformer based on a vector magnetic potential node finite element method; and by simulating magnetic field distribution in the transformer, performing calculation and analysis on a stress on a winding. After the winding deforms, a geometric structure of the winding is no longer regular and a magnetic structure coupling model programmed by utilizing a current loading principle is not applicable, so a winding stress value is calculated from a two-dimensional model corresponding to a three-dimensional model and then the stress value is loaded into the corresponding three-dimensional model through a related program to calculate the stress on the winding. The deformation of the winding is reflected through a difference of the sunken degrees of the winding between two supporting strips, so that the conditions of stresses on the model in different accumulation situations are observed. The method provides a basis for judging the structural stability of the winding of the transformer, and has the advantages of being scientific, reasonable, real, effective, high in practical value and the like.

The invention discloses a metal stress assessment method and system based on intelligent wearable equipment. The method comprises the steps: obtaining physiological parameters of a user in a preset period from the intelligent wearable equipment, and judging whether the physiological parameters of the user in the preset period exceed a prestored range of physiological parameters of the user at a normal metal state; and determining that the user has metal stress if the physiological parameters of the user in the preset period exceed the prestored range of physiological parameters of the user at the normal metal state. Through the above mode, the method and system can assess the condition of metal stress of the user, and enable the user to know the condition of metal stress timely.

A design method for creep-fatigue strength of a plate-fin heat exchanger. The method includes preliminarily designing the plate-fin heat exchanger according to its service requirements, making a primary stress assessment for the plate-fin heat exchanger, calculating the equivalent mechanical and thermophysical parameters of the plate-fin heat exchanger core to satisfy the allowable stress requirement, performing a thermal fatigue analysis for the plate-fin heat exchanger based on these parameters and then calculating the fatigue life and creep life of the plate-fin heat exchanger to accomplish the comprehensive design of the plate-fin heat exchanger in the high-temperature service. The design method provides an effective method for the high temperature design of the plate-fin heat exchanger.

The invention relates to a pipeline stress analyzing and computing technology, in particular to an auxiliary graphical method for rating pipeline stress used for engineering practical problems. The method comprises the following steps of: outputting a quantity which is irrelevant to stress concentration in computed stress and a quantity which is relevant to stress concentration respectively; and partitioning the quantity which is relevant to stress concentration into a quantity before the consideration of stress concentration and a quantity after the consideration of stress concentration, and displaying by using graphics. According to the method, a user can obtain more information from graphics, methods for solving problems can be found more quickly by using graphics, and solving of engineering problems is greatly facilitated.

The embodiment of the invention provides a pressure assessment calibration method and device and a storage medium, and is used for solving the problems of low accuracy and poor user experience of conventional pressure assessment results, wherein the pressure assessment calibration method includes the steps: acquiring a physiological parameter signal of a user, determining the lowest pressure statevalue of the user in the preset length of time based on the characteristic value vector of the physiological parameter signal and a pressure assessment system, determining calibration information according to the lowest standard pressure value and the lowest pressure state value of the user's population, and calibrating the output pressure state value of the pressure assessment system by the calibration information, and determining the theoretical pressure state value of the user. According the pressure assessment calibration method and device and the storage medium, the results of stress assessment can be automatically calibrated, the accuracy of assessment can be improved, the subjective participation of the user is not required, and the user experience can be improved.

The invention discloses a steel box girder evaluation method and system based on monitoring data, and the method comprises the steps of firstly carrying out the preprocessing of the stress time history and temperature information of different monitoring points of a monitored steel box girder, and carrying out the separation through an empirical mode decomposition method, and obtaining a fast-change component and a slow-change component; secondly, extracting stress data according to a multiple linear regression method, and carrying out mutual correction fusion on the stress data, the fast-change component and the slow-change component; then calculating fatigue damage and fatigue life of the steel box girder based on monitoring data, and evaluating the service state of the steel box girder with the fatigue life as an index; and meanwhile, building a steel box girder stress evaluation system, so that the functions of data import, preprocessing, state evaluation and the like are realized. According to the method, the service performance of the main beam can be dynamically evaluated by using the existing monitoring data, damage and diseases of the structure can be found in time, and a theoretical basis can be provided for intelligent early warning of the service state of the key component of the large-span cable-stayed bridge.

The present disclosure generally relates to a measurement device (110) and a method (200 / 300) for stress assessment of a user. The measurement device (110) comprises: a sensor module for measuring anumber of sets of physiological data, each set of measured during a time period; a database (112) for storing the data; a display module (116) for displaying visual information (400 / 420 / 440). Themethod (200 / 300) comprises determining a stress parameter for each set of data for comparison against a predefined stress reference; identifying a first stress parameter for a current time period;generating a stress alert in response to a determination that predefined stress conditions are satisfied based on at least the first stress parameter; and displaying the visual information (400 / 420/ 440) corresponding to the stress alert and assistive to relieving the stress state, wherein the stress conditions are satisfied if the first stress parameter is indicative of a stress state of the user relative to the predefined stress reference.

The invention relates to a high ground stress assessment method, system, device and medium, and the method comprises the steps of obtaining the in-situ longitudinal wave velocity of a rock mass through an acoustic wave test by using an existing engineering investigation drill hole, obtaining the longitudinal wave velocity of a rock triaxial test standard sample through an indoor triaxial test and the acoustic wave test, calculating a cracking coefficient according to the in-situ longitudinal wave velocity of the rock mass and the longitudinal wave velocity of the sample so as to judge whether a wave velocity upside down phenomenon occurs, so that whether the rock mass is in a high crustal stress state or not is evaluated. Compared with a method of independently adopting the acoustic wave test outdoors, the high crustal stress state of the engineering rock mass can be evaluated more accurately. Moreover, the method makes full use of the existing exploration drill hole and rock core in engineering exploration, does not need to carry out additional trepanning test in an engineering area, and can rapidly evaluate the high ground stress state of the engineering area by comparing the acoustic test result of the exploration drill hole with the acoustic test result of the indoor triaxial mechanical test and utilizing the wave velocity upside down phenomenon, and the budget cost can be reduced.

The invention discloses a horizontal storage tank stress evaluation method based on ANSYS software, and belongs to the field of storage tank stress analysis and evaluation methods. On one hand, the invention determines a stress analysis method based on finite element analysis and simulation software ANSYS Workbench to carry out simulation researches such as geometric modeling, grid division, boundary condition setting and result solving on the saddle of the horizontal storage tank and an opening pipe connecting area structure so as to obtain the stress distribution of the storage tank under the condition that the storage tank bears a load. And on the other hand, linear evaluation is conducted on the maximum stress point obtained through finite element analysis, strength checking is conducted on the result by referring to the'pressure vessel analysis design standard ', and whether the storage tank can continue to serve or not is judged according to the evaluation result. The method aims to form a reasonable method for analyzing and evaluating the safety performance of the storage tank, and help is provided for formulating corresponding measures.

The invention discloses a partition decoupling modeling and overall coupling calculation method of a sodium-cooled fast reactor vessel, which belongs to the technical field of nuclear reactor modeling and three-dimensional thermal fluid transient phenomenon algorithm, and specifically establishes a three-dimensional thermal fluid calculation model, Calculate the typical working conditions of the sodium-cooled fast reactor reactor vessel and internal components, simulate the three-dimensional thermal fluid transient phenomenon in the reactor vessel under the typical working conditions including normal operation, expected operation events and accidents, and obtain the normal operation and key The temperature field and flow field distribution characteristics of key structures and components in the reactor under accident conditions, and its three-dimensional thermal distribution and change characteristics are clarified. The three-dimensional thermal parameters obtained based on numerical simulation calculations can provide support and basis for stress assessment of sodium-cooled fast reactor-related structures, and also provide technical reference for numerical simulation of various models with large differences in flow channel size and complex structures.