Abstract: A method and system for determining the potential friction between a tyre and a rolling surface wherein: the tyre is rotated on the rolling surface so as to subject a crown portion of the tyre to an acceleration radial component; data are obtained which are representative of the acceleration radial component to which the crown portion is subjected during at least one tyre revolution; starting from the data, data are selected which are representative of at least one transition region of the acceleration radial component; the selected data are processed so as to obtain information correlated with the steepness of transition of the at least one transition region; and the potential friction is estimated on the basis of the information correlated with the steepness of transition.

Abstract: A system includes a rotor, a rotor antenna attached to the rotor, a strain detection device attached to the rotor, a programmable gain amplifier attached to the rotor, and a control module attached to the rotor. The strain detection device is configured to generate signals that indicate an amount of strain in the rotor. The programmable gain amplifier is configured to amplify the signals generated by the strain detection device by a gain value. The gain value is programmable. The control module is configured to program the gain value of the programmable gain amplifier and transmit, via the rotor antenna, digital data that is derived from the amplified signals.

Abstract: A machine diagnosing device includes a drive object driving force estimating unit for estimating drive object driving force based on a torque command value toward a servo motor which is acquired using a position command value, an elastic deformation error estimating unit for estimating an elastic deformation error of a ball screw with the drive object driving force, and a positional deviation calculating unit for calculating a positional deviation using a rotation position of the servo motor and the position of a table, and a machine damage diagnosing unit for diagnosing a machine damage by calculating a machine damage coefficient using the elastic deformation error and the positional deviation, comparing the obtained machine damage coefficient with a previously set threshold value, and diagnosing a damage state of the drive object.

Abstract: In a method for applying a parking brake of a vehicle depending on the roadway conditions, at least one electromechanical braking system has a parking brake and an operational brake function. An operational brake force is produced on each wheel to slow the vehicle down to a standstill. A parking brake force is generated on at least two wheels of the vehicle. The parking brake forces have an amount that corresponds to the total of the previous parking brake forces applied to all of the wheels and subsequently the stopping of the vehicle is tesste. When the vehicle is maintained in the stop position, the amount of the parking brake force on the at least two wheels is reduced and simultaneously, the service brake forces that are reduced by a certain amount corresponding to the parking brake forces are built up at least on the other wheels.

Abstract: A method for presenting a stress domain includes analyzing, using a cost function, multiple stress ratio values and orientation values to obtain results, generating a stress domain diagram relating the stress ratio values and the orientation values to the results, and presenting the stress domain diagram.

Abstract: A method, apparatus and computer program product is disclosed for determining the strain induced at a selected point in a stiffened panel structure in response to a load, taking into account one or more out of plane (OOP) effects.

Abstract: A system, a method and a computer program to monitor a plurality of transformer operating parameters, as well as to accurately control one or more of the transformer operating parameters. Calculate loss of life and give diagnosis for recovery and provide maintenance notification, monitor the operation of the LTC.

Abstract: Disclosed herein is a method of analyzing load-settlement characteristics of a top-base foundation. The method includes the step of inputting properties of a material of a top base, a basic size of footing configuration, and a load of a structure, the step of inputting the kind of ground and a base ground thickness, the step of determining an influential depth and a load dispersion angle depending on the kind of ground, the step of inputting properties of the ground, the step of determining an immediate settlement amount of the ground, and the step of determining a total settlement amount. The method according to the present invention can precisely determine settlement taking into account footing configuration. Furthermore, the method calculates the settlement taking into account consolidation settlement when the ground is cohesive soil ground or top-cohesive-soil and bottom-sandy-soil ground. Thus, the settlement can be precisely determined.

Abstract: A method for metallic structure maintenance is disclosed. The method includes a magneto-graphic/Magnetic Tomography technique to identify stress-related defects. The method is specifically optimized for extended, non-accessible underground and underwater metallic structures in providing quality control, emergency alarms as well as timeline planning for structural repairs and maintenance work. Examples of the method implementation include pipes for oil and gas industry, detection of flaws in rolled products in metallurgical industry, welding quality of heavy duty equipment such as ships reservoirs, etc. It is especially important for loaded constructions, such as pressured pipes, infrastructure maintenance, nuclear power plant monitoring, bridges, corrosion prevention and environment protection.

Abstract: The distributive elastic properties in nonlinear structures is characterized using an inverse elastostatic approach of stress analysis using assumed elastic models without knowing the realistic material parameters. Stress distributions are computed independently of strain measurements. A database of pointwise stress and strain data in regions of the nonlinear structure permits the elastic properties of the structure to be characterized point-by-point to provide the property distribution.

Abstract: The present system determines a significant stress value (?) of a component made of magnetizable material. The system has a generating stage for generating a magnetic field of varying amplitude (H); and also includes a pickup stage for acquiring a Barkhausen noise signal (MBN) alongside variations in the amplitude (H) of the magnetic field. The system is characterized by having a processing unit for calculating the reciprocal (1/MBNmax) of the maximum value (MBNmax) of the signal (MBN), alongside variations in the amplitude (H) of the magnetic field. The processing unit has a memory stage storing a linear relation between the reciprocal (1/MBNmax) of the maximum value and the significant stress value (?).

Abstract: An interface device for measuring forces applied to the interface device. The interface device has a flexible contact surface suspended above a rigid substrate. The interface device has at least one sensor in communication with the contact surface. The interface device has processing circuitry for receiving signals from the sensors and substantially instantaneously producing an output signal corresponding to the location and force applied in multiple locations across the contact surface.

Abstract: A cast iron brake caliper with improved fatigue life, and a process and process equipment for pre-stressing a cast iron brake caliper to provide improved fatigue life, is provided. In the process, a load is applied to a cast iron caliper, where the load is high enough to locally yield and plastically deform the cast iron material, but not high enough to cause material failure, such as cracking. Upon load removal, residual compressive stresses in the cast iron caliper lower the mid-point of the stress range the plastically-deformed region of the caliper sees during in-service use, and thereby lowers the peak stress seen in this region, increasing fatigue life. The process permits a cast iron brake caliper to be designed to use less material and thus fit within constrained wheel rim envelopes, without the need to resort to high cost materials or other alternative design strategies.

Abstract: The different advantageous embodiments provide a method and an apparatus for measuring forces. In one advantageous embodiment, an apparatus comprising a probe, a force sensor, an angle measurement system, and an output device is provided. The probe is configured to apply a load to a surface of an object. The force sensor is configured to measure a force along an axis through an end of the probe that contacts the surface when the load is applied to the surface by the probe. The angle measurement system is configured to identify an angle of the axis relative to the surface of the object. The output device is configured to display the force and the angle.

Abstract: The disclosure is directed to methods and apparatuses for estimating a response relating to a formation by stressing a wall of a borehole during either wireline or while drilling deployment. The response may be estimated by stressing the wall of a borehole formed in the formation; and estimating a response of the borehole wall to the stress. The response may be estimated using a force module configured to induce the stress around borehole and a tool configured to estimate the response of the borehole wall to the stress.

Abstract: A system for determining the tongue weight of a towed vehicle and other parameters includes a drawbar transducer in one embodiment and a receiver hitch transducer in another embodiment. Strain gauges are strategically located on the transducer and information regarding the towed vehicle are sent to a display. In one embodiment, a portable display unit has a radio frequency transceiver for receiving transmitted data from the transducer reflective of the towed vehicle tongue weight so that a user can view the tongue weight in practically real time. In this manner, the user can adjust the contents of the towed vehicle to achieve proper tongue weight without the necessity of going back and forth between the trailer and the transducer. A method is also disclosed for determining a safe towing condition based on the trailer tongue weight, trailer pulling force, acceleration during towing, and calculated trailer weight.

Abstract: A computational model of the internal human pelvic environment. The model comprises meshed finite element regions corresponding to internal tissues or organs selected from the group consisting of pelvic muscles, vagina, vaginal walls, intestinal tissues, bowel tissues, bladder, bladder walls, cervix, and combinations thereof.

Abstract: The present disclosure provides a strain measuring and monitoring device with displacement sensors for measuring and monitoring the levels of strain and load forces experienced by metallic bars, such as reinforcing bars or rock bolts. The strain measuring and monitoring device includes an array of displacement sensors that directly measure the induced displacement or stretch of the metallic bar being measured over an extended base length. Upon dividing the measured displacement by this longer base-length, an average strain is determined.

Abstract: The overall material constant of a composite material is computed where the composite material includes multiple kinds of material components in a matrix phase, each of the material constants of the material components and the matrix phase being known. First, for the composite material, an equation, having the material constant of a virtual composite material as an unknown, is prepared by defining the virtual composite material in which each of the material components is dispersed in a form of spherical particles in the matrix phase at a known volume fractions. Next, the overall material constant of the virtual composite material is found as the overall material constant of the composite material by solving the equation. In this case, the equation is a recursive equation which is obtained using the self-consistent method. The volume fraction of a material component in the composite material is computed using the equation.

Abstract: A system and method for a surface strain gauge is described which has direct application to wind turbine structures and wind turbine blades and wind turbine struts. The invention is equally applicable to other airfoil structures such as aircraft wings and aircraft fuselages. The strain gauge comprises an array of carbon fibre material integrated with one or more microcontroller modules wherein the entire array may be incorporated into the surface of the structure to be monitored during manufacture of the structure. The array comprises separate sheets of carbon fibre reinforced epoxy which are linked together and which each comprise a separately addressable element such as a microcontroller wherein the microcontrollers are connected to a power supply and to a central bus which itself links to a central system controller. Differential measurements of the resistance of separate carbon fibre reinforced epoxy sheets may be determined in real time as well as the resistance between two or more sheets.

Abstract: A digging machine. The machine includes a rod having a central bore with at least two strain gauges angled relative to each other, a hoist rope, and a CPU configured to create a calibration table of a plurality of outputs from each of the two strain gauges, given various rope tensions and rope angles, determine an unknown rope tension and rope angle, use the output from one strain gauge and create a first set of data point angle and tension pairs from plurality of calibration outputs that correspond to the one output from one strain gauge, use the output from the other strain gauge and create a second set of data point angle and tension pairs from the plurality of calibration outputs that correspond to the one output from other strain gauge, and determine, based on where said two sets of data points intersect, rope tension and rope angle.

Abstract: A strain measuring device is provided which is not affected by a change in the intensity and irradiation direction of light received by a measurement target and which enables stable measurement. A computer functions as minute region extracting device for extracting respective surface height distributions of minute regions a and b containing points A and B in a predetermined region from an initial surface height distribution obtained by measuring the predetermined region (6) of the measurement target by a surface height measuring device, coordinate calculating device for calculating coordinates of points A? and B? in minute regions a? and b? most similar to the minute regions a and b over a time-advanced surface height distribution of the predetermined region 6 and corresponding to the points A and B in the minute regions a and b, respectively, and strain calculating device for calculating a strain in a direction of a line AB of the measurement target.

Abstract: A fracture determination method for determining a fracture of a metal structure includes, when a fracture determination target portion has returned from a plastic state to an elastic state, given that a stress when the portion returned to the elastic state is (x, y)=(?2, ?1) (maximum principal stress: ?1, minimum principal stress: ?2) on a (x, y) coordinate plane, performing fracture determination of the fracture determination target portion using a re-yield stress R determined by the intersection between a straight line satisfying a relation y=(?1/?2)x and an yield curve obtained from the plastic state of the fracture determination target portion. Fracture determination can be performed with high accuracy even when the fracture determination target portion has returned from a plastic state to an elastic state.

Abstract: There is provided a sensor equipped wheel support bearing assembly including an outer member having an inner periphery formed with a plurality of rolling surfaces defined therein, an inner member having an outer periphery formed with rolling surfaces opposed to those rolling surfaces and a plurality of rows of rolling elements interposed between those rolling surfaces. One of the outer and inner members serving as a stationary member is provided with a strain amplifying mechanism for amplifying a strain in the stationary member, which occurs when the rolling elements pass by. A strain sensor element is provided for detecting the strain amplified by the strain amplifying mechanism. A calculator is provided for calculating from an output of the strain sensor element, the load acting on the bearing assembly or the load acting between the vehicle wheel and the road surface.

Abstract: An ultrasound machine processes ultrasonic data according to acoustoelastic properties of the materials to obtain strain information without specific assumptions with respect to the material properties of the measured material or a variety of different material properties normally not obtained by ultrasound machines.

Abstract: A resilience and displacement measuring device is configured with a shaft having a displacement detection module and a force detection module disposed respectively at the two ends thereof. When the shaft is moved for driving a probe of the force detection module to press on a tested press-key, a reflective panel in the displacement detection module will be caused to displace along with the moving of the shaft for allowing a light sensor to measure the displacement of the shaft, and at the same time the pressing of the probe on the press-key will force a detection film to deform for allowing a strain gauge to measure a resilience. The device is capable of dividing a measurement range into a plurality of sub-ranges while designing calculation models specifically for the sub-ranges, by that a precise distance can be obtained from the measured distance information of the calculation models.

Abstract: A new type of magnetoelastic device for sensing force is described. It comprises of two elements: a circumferentially magnetized member comprised of magnetoelastically active material mounted as a beam and loaded by the force to be sensed, and a magnetic field sensor mounted at or near the member's surface, preferentially at or near a longitudinal location where the bending moment is maximum and at a circumferential location where the bending stress is zero. Flexural loading causes a variation of the circumferential magnetization with angular position. This variation is the source of free poles, the field from which is a measure of the applied force. Testing demonstrates that the field intensity is a linear analog of the experienced bending stress over a significant range of applied push and pull forces.

Abstract: The present invention relates to an apparatus and a method for calculating a fatigue usage factor with respect to fatigue generated in the material of a mechanical device depending upon changes of an operation environment during operation of the mechanical device. A fatigue usage factor UOP.cyc,transient n, which is based on the operation-transient state n, is calculated by multiplying a fatigue usage factor based on a design-transient state UDSGN.cyc,transient n by the value of a characteristic fatigue usage factor F (k) as shown in the following equation: UOP.cyc,transient n=F(k)×UDSGN.

Abstract: An in-plane compressive strength evaluation device (10) provided with a memory unit (21) into which, when an in-plane compressive strength evaluation is actually performed using a test piece, an evaluation result is stored as first information; a first analysis unit (22) that obtains second information that is an evaluation result related to the load and a displacement of the structural model; an adjustment unit (23) that adjusts an elemental factor of the structural model that influences the in-plane compressive strength such that the second information approaches the first information; and a second analysis unit (24) that, in a state where the elemental factor used when the second information approaches the first information most closely expands the structural model into the structural form of the actual tube support plate, and that performs the in-plane compressive strength evaluation using the expanded structural model.

Abstract: A continuous geomechanically stable trajectory in a subterranean formation is found by calculating at least one reachable stable position relative to a starting position based on geological data indicative of characteristics of the subterranean formation, and iteratively utilizing the calculated reachable stable position as a new starting position. The calculation may be constrained by a boundary including selected distance and direction relative to the starting position, and selected rate of angle change. Within the constraints of the boundary, the possible new trajectories considered may be discretized. The result of the calculations is a three dimensional tree which defines a stability volume. Pruning of at least some branches of the tree may be employed so that not all stable positions have the preselected number of branches, thereby helping to elongate the tree. Either or both of the tree and stability volume are used to select at least one trajectory.

Abstract: A method of determining the fatigue life of a structure includes the steps of: associating a mathematical equation for total strain amplitude with the structure: ?? 2 = ? f ? E ? ( 2 ? N f ) b + ? f ? ? ( 2 ? N f ) c , where: ??/2=strain amplitude, ?f?=fatigue strength coefficient associated with a material of the structure, b=fatigue strength exponent of the material, E=cyclic modulus of elasticity of the material, 2Nf=number of cycles, ?f?=fatigue ductility coefficient of the material, and c=fatigue ductility exponent of the material; reducing the fatigue strength exponent (b) such that an elastic portion of a total strain amplitude curve associated with the equation has a reduced slope to account for variable amplitude loading for the structure; generating a total strain amplitude curve, based upon the mathematical equation: ?? 2 = ? f ? E ? ( 2 ? N f ) b reduced + ? f ? ? ( 2 ? N f ) c , where (breduced) is now

Abstract: A system for electronically recording an event that provides mechanical energy to a structure includes the structure and an event sensing and recording node. The event sensing and recording node is mounted on the structure and includes a sensor and a first electronic memory. The sensor includes a device for converting the mechanical energy into an electrical signal. The first electronic memory uses energy derived from the electrical signal for electronically recording the event. All energy for sensing the event and recording the event in the first electronic memory is derived from the mechanical energy.

Abstract: Disclosed is an air gap measuring apparatus, for measuring width of an air gap formed between a rotator and a stator. An insertion section has a first flat plate section and a second flat plate section. Gap adjusting means drives the second flat plate section such that the second flat plate section moves away from the first flat plate section, until the first flat plate section and the second flat plate section abuts on the rotator and the stator. An operating section extends to outside of the insertion section, and operates the gap adjusting means. An elastic body has an end that follows the first flat plate section, and other end that follows the second flat plate section. A strain gage outputs electrical signals corresponding to the strain of the elastic body, the strain being formed due to the movement of the second flat plate section.

Abstract: An internal residual stress calculating device includes a prediction unit that predicts a temporal variation in deformation which is received by a medium having an image formed thereon from a correcting device correcting a deformation, and a calculation unit that calculates an internal residual stress of the medium having passed through the correcting device on the basis of a relational expression including an elasticity term and a term related to a plastic deformation and the temporal variation in deformation predicted by the prediction unit.

Abstract: A loaded wheel tester for testing asphalt mixtures comprises a loaded wheel tester having additional means for attachment to specimens under test to provide a measurement of tensile strain and for attachment between a frame of the loaded wheel tester and the loaded wheel to determine position of the loaded wheel over time. Output results demonstrate that viscoelastic and fatigue properties of asphalt mixtures are obtained in equivalent or improved format using a modified loaded wheel tester when compared with known pavement test apparatus and methods.

Abstract: Board warp analysis includes dividing a temperature profile with respect to an electronic component by a predetermined time. A relaxation elastic modulus of the electronic component corresponding to the divisional time is obtained by shifting on a time base of a master curve related to the electronic component A curing degree of the electronic component is calculated based on a relationship between a time after shift and an actually applied temperature. A warp of the electronic component is analyzed based on a relaxation elastic modulus on the master curve or a relaxation elastic modulus calculated based on a relationship between the curing degree and the elastic constant according to a value of the curing degree calculated.

Abstract: The invention relates to a method for dimensioning, by an analytical method, of an essentially plane panel consisting of a homogenous and isotropic material, said panel consisting of a skin reinforced by a set of three parallel bundles of stiffeners built into the panel. The pockets determined on the skin by said groups of stiffeners are triangular, the stiffeners are blade shaped and the stiffened panel must comply with specifications for mechanical resistance to predetermined external loads, the angles between bundles of stiffeners being such that the triangular pockets have any kind of isosceles form.

Abstract: A method for monitoring stress on a wind turbine blade during loading is disclosed. The method includes capturing multiple images at respective locations of the blade. The method also includes measuring temperature at the respective locations based upon captured images. The method further includes calculating stress applied on the blade at the respective locations based upon the measured temperature. The method also includes calculating stress applied on the blade at the respective locations based upon the measured temperature. The method further includes comparing the calculated stress with respective theoretical stress in a finite element model to predict lifetime of the blade. The method also includes alerting an operator in event that the calculated stress at one or more of the respective locations is above a pre-determined limit.

Abstract: A method for producing a missile nose cone is disclosed. The method consists of manufacturing a first missile nose cone from a first lot of polymeric material and determining a first rupture value. The method further consists of manufacturing a second missile nose cone from a second lot of polymeric material and determining a second rupture value of the second missile nose cone. Both first and second lots of material are mixed into a test batch with one another based on their associated rupture values. An evaluation missile nose cone is then manufactured from the test batch and a determination is made as to whether the evaluation missile nose cone has a desired rupture value. If a desired rupture value is not obtained, then the mixing and evaluation steps are repeated.

Abstract: A method and device for determining critical buffeting loads on a structure of an aircraft is disclosed. The device (1) comprises means (2, UC) implementing a semi-empirical method for determining the critical loads generated by some buffeting on the structure of the airplane.

Abstract: A method for determining when a ceramic component on a platform should be replaced. The method includes determining parameters for the ceramic component, the parameters include empirically determined a critical stress intensity factor, and a geometry factor for the ceramic component. The method also includes determining a relationship between platform operational parameters to the generation of stress at the surface of interest of the ceramic component, determining an initial crack size of a crack within the ceramic component at installation, tracking operational parameters of the platform throughout a course of usage of the ceramic component, calculating the corresponding stress at the crack location due to the tracked operational parameters, and calculating a numerical solution that illustrates a crack growth rate velocity and tracks a size of the crack over time. The ceramic component is replaced based on the crack growth rate velocity and the size of the crack.

Abstract: A load is based calibrate on data collected under wide observation conditions and promptly calibrate loads of a plurality of wind turbine blades. A load measuring apparatus is applied to a wind turbine in which a pitch angle of a wind turbine blade is variable. The apparatus includes a sensor for obtaining a distortion of the wind turbine blade; a load calculating unit having a function expressing a relation between the distortion of the wind turbine blade and a load on the wind turbine blade, for obtaining the load on the wind turbine blade by applying to the function the distortion based on measurement data of the sensor; and a calibration unit for calibrating the function based on the measurement data of the sensor obtained in a pitch angle range and a rotational speed range of the wind turbine blade in which a variation between maximum and minimum aerodynamic torques is equal to or less than a predetermined value.

Abstract: Storage of information, such as baseline information and structure ID, in a memory that is mounted on the structure, rather than inside the diagnosis hardware. This allows for faster and more convenient information retrieval. In particular, this approach allows for a more modular system in which different diagnosis hardware or other analyzers can be simply plugged into a structure's sensor network, whereupon they can quickly download any desired structure-specific information (e.g., baseline information, structure ID, and other useful information) from the on-structure memory.

Abstract: The computation of a Load Factor, a Life Factor or a Load Enhancement Factor using Modified Joint Weibull Analysis may include retrieving a test data set from at least one database and analyzing the data retrieved for fit with a Weibull distribution model. The test data may be analyzed to determine if at least two coupons have been tested and if applied loads and duration of testing at a component-level were varied. A shape parameter may be calculated for the Weibull distribution model. A scale parameter may be calculated for the Weibull distribution of the data. A stress to life cycle relationship may be calculated to account for scatter in the data through the Weibull distribution data. The Life Factor, the Load Factor or the Load Enhancement Factor may be calculated based on the stress to life cycle relationship to account for scatter.

Abstract: Methods and systems for data smoothing raw data such as stress data. The present invention may utilize various techniques to smooth data such as dropping data using a stress threshold, dropping data by resample (or decimation), and smoothing by dynamic binning. Additionally, the present invention may utilize a transform function to estimate stress from a stress sensor to areas of peak stress. In an exemplary application, the present invention can be utilized to reduce stress data collected by a plurality of embedded stress sensors in a rocket motor for purposes of computing service life of the motor.

Abstract: A wind turbine rotor blade having a strain sensor system is described. The strain sensor is insensitive to the effect of twisting motions or edge-wise bending on the measurement of the strain. The sensor comprises one or more strain sensing devices arranged in a circular or regular polygon shaped path enclosing a region of the component. In the sensor system, a plurality of strain sensors are spaced longitudinally along a flap-wise axis of the wind turbine rotor blade.

Abstract: A system measures the strain of an object. The system includes a laser source for generating an output radiation, a strainable optical fiber having first and second facets, and means for calculating a measure of a strain of the optical fiber. The first facet is coupled to the laser source to receive the output radiation and transmit a guided radiation over the optical fiber towards the second facet. The second facet is adapted to receive the guided radiation and to reflect a corresponding reflected radiation towards the first facet. The laser source is a self-mixing type adapted to receive at least part of the reflected radiation and to mix the output radiation with the received radiation. The calculating means calculate the measure of the strain of the optical fiber based on a self-mixing effect in the laser source that is caused by the linear displacement of the second section.

Abstract: Apparatus and methods for measuring a dynamic deformation characteristic of a deformable target surface during a deformation interval. The measurement principles may be applied to a large variety of organic and inorganic materials having a surface that can be deformed by an applied non-contact force. The surface may be light diffusing and non-transparent or non-diffusing and transparent. A device for measuring a dynamic deformation characteristic of an in-vivo cornea during a deformation interval includes a corneal topographer and an air puff generator that are operationally integrated. Use of the inventive device enables a method for making a measurement of a deformation characteristic of the in-vivo cornea during a deformation interval, further allowing a determination of spatially-resolved in-vivo corneal biomechanical and biodynamic properties such as corneal elasticity and corneal viscosity.

Abstract: A method, test circuit and test system provide measurements to accurately characterize threshold voltage changes due to negative bias temperature instability (NBTI) and positive bias temperature instability (PBTI). Both the bias temperature instability recovery profile and/or the bias temperature shifts due to rapid repetitions of stress application can be studied. In order to provide accurate measurements when stresses are applied at intervals on the order of tens of nanoseconds while avoiding unwanted recovery, and/or to achieve recovery profile sampling resolutions in the nanosecond range, multiple delay or ring oscillator frequency measurements are made using a delay line that is formed from delay elements that have delay variation substantially caused only by NBTI or PBTI effects. Devices in the delay elements are stressed, and then the delay line/ring oscillator is operated to measure a threshold voltage change for one or more measurement periods on the order of nanoseconds.

Abstract: A two-dimensional matrix code containing dark and light square data modules, and a finder pattern of two bars of alternating dark and light square data modules on the perimeter of the symbol for indicating both orientation and printing density of the symbol, wherein all of the data modules are the same dimension and data is encoded based on the absolute position of the dark modules within the matrix, and inner and outer bars are provided along adjacent sides of the matrix code symbol, each bar having a width equal to the square data modules. In one embodiment, the inner and outer bars are solid. In another embodiment, the inner solid is bar and the outer bar is an encoding bar.