A method of estimating aging of an integrated circuit (IC) includes: obtaining a first process design kit (PDK) including a plurality of first device models corresponding to a plurality of devices provided by a process of fabricating the IC; obtaining values of aging parameters of device instances included in a netlist defining the IC, by performing a first circuit simulation based on the netlist and the first PDK; and obtaining aging data of the IC by performing a second circuit simulation based on the values of the aging parameters and the netlist, wherein each of the plurality of first device models includes at least one measurement command to be executed in the first circuit simulation to calculate an aging parameter.

Due to geometric discontinuities introduced by welding and joining processes, stresses or strain cannot be calculated reliably calculated using modern analytical and computer methods as result of stress or strain singularity at joint locations, which leads to severe mesh sensitivity. Design and fatigue evaluation of these structures remain empirical. This disclosure addresses mesh insensitivity of stress/strain calculations for welded structures through a cut-plane traction stress method through a novel post processing of conventional finite element computation results, as well as provides a unified fatigue evaluation procedure for fatigue design and structural life evaluation for both low-cycle and high cycle fatigue regime subjected to either proportional or non-proportional multiaxial fatigue loading, as well as a simple and reliable method for treating spot welds.

A control device including a solder joint life predictor includes: a temperature sensor that measures temperature of a solder joint on an electronic circuit board that drives a heater and a motor; a storage that stores a reference acceleration factor that is an acceleration factor based on a test condition of a thermal shock test and a reference condition in an environment in which the electrical appliance is used; a calculator that calculates an actual acceleration factor from a temperature variation range and a maximum reached temperature of the solder joint during one cycle from start to end of driving of the heater or the motor; and a determiner that predicts the life of the solder joint by comparing the integrated value of the acceleration factor ratios with a threshold.

The invention concerns a method for determining a mechanical stress of a runner (40), of a hydraulic machine (10), wherein the runner is arranged to rotate around a rotation axis, wherein the hydraulic machine comprises a hydraulic channel delimited by hydraulic surfaces of the runner, the hydraulic surfaces being the surfaces against which a stream of water exerts the forces when the runner is driven in rotation by said stream of water, wherein the runner further comprises a sensor (G) on protected areas positioned away from the hydraulic channel, the method comprises the steps of: a) collecting a physical quantity measured by the sensor (G), b) determining a mechanical stress on a specific location of the hydraulic surface, via a transfer function that correlates the physical quantity measured in step a) and said mechanical stress on the specific location.

A system and method of simulating device aging based on a digital waveform representative of a workload of an electronic device are disclosed. In one aspect, the method comprises grouping contiguous sets of cycles into segments, each set corresponding to a segment. Each segment has values for a combination of segment parameters that are unique from each of the other segments and a start point that is separated from a start point of an adjacent segment by a pre-defined distance criterion. Grouping the sets into the segments comprises, for each segment: sampling one or more sequential cycles of the workload, generating the segment based on the sampled contiguous cycles having a period exceeding a threshold period, and determining the values for the combination of segment parameters. The method further comprises applying an aging model to the segments to simulate the aging. The segments are a representation of the digital waveform.