335 results about "Stress variation" patented technology

The invention discloses a device for monitoring the state of a power transmission line tower-line system, which fully utilizes the advantages of corrosion resistance, wide operation temperature range, anti-electromagnetic interference, passivity, long measuring distance, reliable operation and long service life and the like of optical fiber sensors to configure the optical fiber sensors on a transmission conductor and a tower in a quasi-distributed structure for detecting the temperature, the strain and the acceleration of the transmission conductor and the multipoint stress variation on the tower which are transmitted to an optical modulator demodulator for demodulating and are sent to a computer analyzing and processing system for calculating to obtain the icing quality, the waving amplitude, the breeze vibration amplitude and frequency and the sag of the transmission conductor, and the inclination angle of the tower, thus realizing the simultaneous monitoring on the icing, the waving, the breeze vibration and the sag of the transmission conductor, and the inclination angle state of the tower, and being capable of finishing long-time reliable operation under the on-site severe environment conditions.

A gas detection method capable of solving the problem with respect to the operation at normal temperature that was impossible so far in the existent catalyst type sensor and detection with high sensitivity that was impossible by the light absorption type sensor. A multi-layered film formed of a first layer adsorbing a specified gas and a second layer having less adsorption are utilized as a detection film, and the detection film is disposed in the direction perpendicular to the optical channel and optically detects the change of stress caused in the detection film by gas adsorption as coupling loss. Alternatively, the stress generated in the detection film caused by gas adsorption is electrically detected by a piezoelectric element or capacitance element.

A computer-based system generates digital and audio responses to changes in fluid and rock properties of a producing hydrocarbon reservoir for surveillance analysis. The system calibrates observed changes against directly-measured field data in order to optimize the reservoir model. The changes may include, for example, stress changes in rock, impedance changes in rock, and fluid density changes.

System and method for compact model algorithms to accurately account for effects of layout-induced changes in nitride liner stress in semiconductor devices. The layout-sensitive compact model algorithms account for the impact of large layout variation on circuits by implementing algorithms for obtaining the correct stress response approximations and layout extraction algorithms for obtaining the correct geometric parameters that drive the stress response. In particular, these algorithms include specific information from search “buckets” that are directionally-oriented and include directionally-specific distance measurements for analyzing in detail the specific shape neighborhood of the semiconductor device. The algorithms are additionally adapted to enable the modeling and stress impact determination of a device having single stress liner film and dual-stress liners (two different liner films that abut at an interface).

The invention relates to a method for measuring welding residual stress-a partial layer-by-layer blind hole removing method for measuring the residual stress on the basis of a blind hole method, which proposes to measure the residual stress in a component by using the partial layer-by-layer blind hole removing method. After materials of certain depth on both the front side and the opposite side of a component to be measured are partially removed, the blind hole method is used for measuring the residual stress. The method is a semi-destructive residual stress measuring method, can be used for carrying out multi-point measurement and measuring the residual stress in the component with severe stress change and has convenient operation and high measuring efficiency. Proved by a thick plate carbon steel welding residual stress measuring test, the method has more accurate measuring results.

A pulse wave measuring device is provided with a plurality of pulse wave measuring units. Each pulse wave measuring unit has a supporting member to which a beam of a pressure measuring device is attached. Contact portions at the distal end of the beam is in contact with the patient's arm, so that piezoelectric elements mounted on the beam measures the stress variation according to pulsation of the patient's radial artery. The supporting member has two pressing legs between which the contact portions of the beam are situated. The distal ends of the pressing legs are also pressed against the patient's arm. The pressing legs are harder than the radial artery. The interval between the pressing legs can be altered by handling a micrometer head. The contact portions are situated back from the distal ends of the pressing legs.

Apparatus and methods are provided for reducing the variability of stress levels in glass sheets (11) cut from a moving glass ribbon (13). The reductions in variability are achieved by constraining the edge regions (53,55) of the ribbon (13) from movement in a horizontal plane at at least one location below the location where a separating assembly (20) forms a separation line (47) in the ribbon (13). Sets of vertically arranged wheels (35) which engage the edge regions (53,55) of the ribbon (13) can be used to provide the horizontal constraint without compromising the central, quality area (51) of the glass ribbon (13).

In a vertical glass drawing process, an edge guiding assembly (33) located between a glass forming apparatus (41) and a glass sheet separating apparatus (20) reduces horizontal motion of the glass ribbon (13) from which the glass sheets (11) are removed and results in the reduction of the difference in stress levels between the top and bottom edges of a glass sheet (11) made by the process. The edge guiding assembly also provides a reduction of the variation of stress levels between successive sheets of glass made by the vertical drawing process.

Disclosed are a testing apparatus for and a method of measuring thermal stresses of concrete structures. Overcoming the limitations that conventional analytical access techniques have, the apparatus opens a new way to conveniently measure the thermal stress attributable to the heat of hydration generated in concrete structures indoors. Using a material different in coefficient of thermal expansion from concrete, the apparatus can directly measure the change in thermal stress of the concrete which is subjected to internal and/or external confinement. By using various materials, the thermal stress which varies depending on the confinement extent can be inferred. Additionally, an accurate prediction of the thermal stresses generated actually in concrete can be obtained, reflecting unclear physical properties of early-age concrete.

The invention relates to a method for testing residual stress of a steel rail. The method is characterized by comprising the following steps of using a steel rail with the length of 1m, taking one point (namely a center position) 500mm away from the end of the steel rail, drawing a line which is arranged at the point in the circumferential direction vertical to the axis of the steel rail, sequentially and alternatively taking 14 points from the center point of the rail bottom to the center of the rail head in the linear direction, attaching each point with a strain sheet, measuring the initial value of the residual stress of each point by a static stress-strain gage, using the line drawn on the steel rail as a center line, cutting steel rail into 20mm thin sheets at each 10mm part of the two ends of the center line in the direction vertical to the axis of the steel rail, and then measuring the final value of the residual stress of each point by the static stress-strain gage. The method has the advantages that by adopting the multi-point testing, the stress distribution conditions of the rail bottom, the rail waist, the rail head and other parts are acknowledged, the stress change of each point is analyzed, then the pressing amount of a rolling machine is corrected, and the distribution of the residual stress is adjusted, so the steel rail is qualified.

The invention discloses a vibration aging method, comprising a computer, a magnetostrictive vibration exciter, an acceleration sensor and a dynamic strain sensor. The vibration aging method is characterized in that the vibration exciter loads on the workpiece and exerts a cyclist exciting force, two sensors are respectively positioned on the easily cracking and deforming area of the workpiece, the sensors are analyzed and different frequency, the corresponding relationship between the dynamic strains and sorting are done by the computer, selecting the frequencies corresponding to the first biggest dynamic strains as the typical vibration, adjusting the working current and time of the vibration exciter, making the vibration exciter to vibrate at the above frequency till the aging is finished. The vibration aging method has the advantages of using the magnetostrictive vibration exciter as a vibration source, regulating the exciting force by the computer, timely responding the vibration variation to meet the dynamic stress, controlling the vibration source to vibrate at the resonation frequency by the computer, timely tuning the output current of the vibration exciter, analyzing and judging the vibration mode and the vibration time of the vibration aging, lively measuring the dynamic stress variation, and outputting the correct remaining stress variation as the prove for the experiment.

The invention provides a method for forecasting the high-temperature-alloy creep life. The method includes the steps that on the basis of the theta projection method, the factor that changes of true stress are caused by changes of the material shape in the creep process is introduced, the correction theta projection method is obtained, and the concrete form is epsilon= theta1*(1-exp(theta2*(1+theta5*epsilon)*t))+theta3*(exp(theta4*(1+theta5*epsilon)*t)-1). The method can be used for forecasting a creep curve at the whole homogeneous deformation stage through initial data from the first stage to the third stage of the creep curve, and the obtaining time of creep data can be shortened. Meanwhile, the method can be used for forecasting creep curves under other creep conditions, and the forecasting process comprises forecasting of the creep rupture time under the some creep condition and the creep interruption time corresponding to some creep strain. The method is simple, reliable and suitable for different-type high temperature alloy and engineering application, and has broad prospects in the aspect of high-temperature-alloy creep life management.

A method of determining stress variations over time in an undersea pipe for transporting fluids, the method comprising: installing along the entire length of the pipe (1) at least one distributed optical fiber sensor (2-1 to 2-4) using Rayleigh backscattering, the sensor being dedicated to measuring at least one degree of freedom of movement variation over time in the pipe at each cross section of the pipe; continuously measuring movement variation of the optical fiber sensor over time; and determining stress variations over time at each point in the pipe by time integration of the measured movement variation of the optical fiber sensor.

The invention provides an annular shearing experiment equipment and a testing method, the annular shearing experiment equipment includes a support seat, a shear box assembly located on the support seat, and a load applied to soil samples in the shear box assembly The loading device, the loading device includes a vertical vibration loading device and a horizontal shear vibration loading device, and the annular shear experimental equipment further includes a load control device for controlling the loading of the vertical vibration loading device and/or the horizontal shear vibration loading device. device. The vertical vibration loading device and/or the horizontal shear vibration loading device can apply vibration loads of different frequencies and amplitudes, which is beneficial to study the influence of dynamic loads on soil strength parameters, more conducive to simulating the actual stress situation, and conducive to revealing The stress changes, pore water pressure changes, local soil damage and liquefaction phenomena occurred during the shear test of the soil under the action of vibration loads, and then reveal the occurrence and movement mechanism of geological disasters such as landslides from the mechanical properties.

The invention discloses a borehole stress sensor. The sensor comprises a metal tube with a longitudinal opening, a strain gauge, a waterproof pressed film, a concrete core and a signal transmission line. The metal tube with the opening which integrates the strain gauge, the signal transmission line and the waterproof pressed film is used for drilling and filling the core with concrete in site application; and the borehole stress sensor is completely manufactured and laid synchronously. The invention also discloses a borehole stress monitoring method based on the sensor. The method has the beneficial technical effects of being capable of effectively testing a stress change process of rock media at different depths in a borehole by the borehole stress sensor, effectively defining a 3D area with unsafe and less-safe rock body on a slope by joint application of a plurality of borehole stress sensors, disclosing a planar distribution range and a depth expansion range of the area, and providing an important scientific basis for subsequent project treatment and safety monitoring.

The invention discloses a landslide advancing sliding force physical simulation experimental method and a device therefor. A stress sensor is utilized to detect the inner stress change of a sliding body on an inclined plane of a sliding bed model, and the curve of the relationship between the magnitudes of the sliding force applied on the sliding body before sliding, in sliding and after sliding and the time can be determined by combining the data of displacement of the sliding body detected by a displacement sensor, so that the value of the curve and the inner stress can be displayed; when in subsection alarm, the detection and the display of the advancing sliding data of the sliding body can be completed, so that the advanced and real-time pre-warning and warning of landslide geological disaster can be really realized. The whole device is reasonable in design and convenient for use, and completely imitates the whole process of landslide for simulate monitoring and information processing; the drawn monitoring curve is authentic, vivid and reliable; an electronic display device can visually and conveniently display the value of the stress, so that the change characteristics of the sliding force in the whole process of landslide can be fully reflected, and the simulation is accurate and vivid.

A MEMS device such as a grating light valve™ light modulator is athermalized such that the force required to deflect the movable portion of the MEMS device remains constant over a range of temperatures. In MEMS embodiments directed to a grating light valve™ light modulator, a ribbon is suspended over a substrate, and the ribbon tension is kept constant over a temperature range by adjusting the aggregate thermal coefficient of expansion of the ribbon to match the aggregate thermal coefficient of expansion of the substrate. Various opposition materials have an opposite thermal coefficient of expansion as the aluminum layer of a grating light valve™ light modulator ribbon, using the thermal coefficient of expansion of the substrate as a zero coefficient reference. The adjustment of the thermal coefficient of expansion of the ribbon can be performed variously by thickening existing layers of opposition material or adding additional layers of new opposition material to the ribbon, or reducing the aluminum in aluminum layer. The aluminum layer may be reduced variously by reducing the thickness of the aluminum layer, or reducing the surface area that the aluminum covers, or reducing both the surface area and the thickness. Embodiments may combine the reduction of aluminum with the use of opposition materials.

The invention relates to lateral compression performance measuring method and device of fibrous material, comprising the parts of fiber lateral cimpression element using pressure head on cantilever beam to lateral compress filament and overlapping fiber sample in multiangular tray, fiber deformation observing parts using two objectives with different direction finish stereo-observation and measurement to compressed fiber, compressive stress measuring elements with deflection correction to put in real time change of stress of pressure head in computer and the deflection correction is to correct vertical compressed displacement by small deflection deflection of cantilever beam when laser reflects measuring compression. By using multiple measurement of stress and conformational change and compact and novel design, lateral compression shape measurement is fast, accurate, overall, its measurement error has decreased greatly and the method is suitable for various kinds of fibrous material.

To minimize stress variations applied to mother glasses when a glass sealing material is melted via a laser to combine the mother glasses, a method of manufacturing a flat panel display device includes providing a plurality of emission units between a first substrate and a second substrate, wherein the first substrates faces the second substrate and each emission unit forms a unit display device; providing a plurality of walls between the first substrate and the second substrate, wherein each wall respectively surrounds one of the emission units; irradiating a laser beam onto the walls, wherein the laser beam is simultaneously irradiated to wall portions aligned in a row in a first direction; scanning the laser beam in a second direction, wherein the second direction is different from the first direction to irradiate other wall portions of the plurality of walls; and cutting the first and second substrates to obtain individual display devices.

The invention provides a cleaning blade, which realizes cleanness by contacting the surface of parts needing cleanness with the blade, and it is characterized in that the material of contact site of said cleaning blade and said parts surface satisfies at least the following inequality (1)-(3): inequality (1)3.92<=M<=29.4. 2;inequality 0<=alpha<=0.294; inequality (3)S>=250, ( in the inequality (1)-(3), M represents 100% modulus (MPa); alpha represents the ratio of stress variation (delta stress) to strain variation (delta strain) [delta stress/delta strain= (the stress under 200% degree of strain - the stress under 100% degree of strain)/ (200-100) ] (MPa/%)in the rang of 100%-200% strain degree and in stress-strain curve; furthermore, S represents elongation at break (%)determined with JIS,K6251(using dumbbell-type the third test piece). The invention also provides a cleaning arrangement containing a cleaning blade, a processing box and an image-forming device.

A fluid properties measurement apparatus for use with a conventional high temperature high pressure test cell includes a load cell assembly and a drive motor that drives a rotating shaft magnetically connected to a vane assembly having multiple vane elements, wherein the motor rotates in response to reactive forces of a fluid sample and the load cell assembly measures reactive forces of the sample. In one embodiment, a stepper motor allows for precise shaft rotation.

A method of measuring fluid properties includes frequent measurements throughout a complete rotation cycle of a vane assembly within a test cell. A system interference profile is generated which identifies stress variations resulting from various system components throughout the cycle. Measurements of a sample's fluid properties are likewise performed to obtain a profile. Comparison of the sample profile with the interference profile provides fluid properties measurement independent of stress variations resulting from various system components.

Metal pastes and methods make it possible to produce extremely compact layers between contact surfaces of structural components, which layers are sufficiently elastic to permanently withstand mechanical and thermal stress variations. This is achieved by the porosity of a corresponding contact area being controlled. For this purpose, a metal paste is provided which contains 70-90% by weight of a metal powder, 1-20% by weight of an endothermically decomposable metal compound and 5-20% by weight of a solvent having a boiling point or range above 220° C., the metal paste being compactable exothermically to form a metal contact.

The invention discloses a three-dimensional simulating method for goaf fracture ring morphology. The method comprises the steps that according to the space similarity ratio between a coal seam and overlaying rock and time similarity ratio of coal seam working face propelling, a three-dimensional similar simulation test body is manufactured; according to the site mining working face ground stress situation and the mining sequence, the dynamic process of coal mine working face propelling under the three-dimensional stress condition is simulated; an embedded stress sensor is utilized for monitoring stress changes of a top plate and a bottom plate of a goaf in the mining working face propelling process, and a dynamic resistance strain gauge is utilized for recording data; after mining working face propelling simulation is finished, a tracer agent labeling method is used for carrying out drilling to pry and observe the goaf fracture morphology of the simulation test body, the top plate and the bottom plate of the goaf are separated layer by layer and section by section, and statistics is carried out on fracture data of all layers and all sections; according to the statistical fracture data, three-dimensional software is utilized for drawing a goaf fracture ring morphology simulation image. The method has the advantages that a three-dimensional mode is adopted for simulating the goaf fracture development morphology, and therefore the position of extraction holes can be determined conveniently and accurately.