A system for measuring mechanical properties of rock cuttings includes a vibration platform with an upper surface configured to vibrate a plurality of rock cuttings thereon. A sensor system is operatively connected to the vibration platform to monitor the rock cuttings vibrating on the upper surface of the vibration platform. A calculation module is operatively connected to the vibration platform and the sensor system to calculate mechanical properties of the rock cuttings based on applied vibrational force frequency of the vibration platform and measurements of the rock cuttings from the sensor system.

A method of monitoring a condition of a dynamic system includes installing a vibration signal acquisition device at a predetermined location of the dynamic system, acquiring vibration signals by the vibration signal acquisition device, analyzing the vibration signals in a frequency domain, and predicting a change in the condition of the dynamic system based on the vibration signals in the frequency domain. A system is also provided, and a condition of the dynamic system includes clogging.

A frequency domain feedforward compensation method based on a power exponential method for a seismic simulation shaking table is provided. According to the method, a frequency domain amplitude transfer function of a system is identified, the frequency domain amplitude transfer function is modified by adjusting the power and limiting an amplitude, then an inverse frequency domain amplitude transfer function is obtained, an amplitude and a phase of a driving acceleration signal are computed, finally a time domain driving acceleration signal is obtained by using the Euler's formula for computation in a complex domain and conducting inverse Fourier transform, the shaking table is driven again to collect an acceleration signal output by a table top, whether the acceleration signal meets a shaking table test waveform use requirement is determined, a test is finished under the condition that the acceleration signal meets the shaking table test waveform use requirement.

A resonance detection system includes a vibration simulation mechanism and a vibration audio analysis device. The vibration simulation mechanism includes a mechanism body that accommodates a peripheral interface device. The vibration simulation mechanism generates a vibration wave to the peripheral interface device. The peripheral interface device generates a vibration audio signal in response to the vibration wave. The vibration audio analysis device is electrically connected with the vibration simulation mechanism. After the vibration audio signal is inputted into the vibration audio analysis device, the vibration audio analysis device judges whether there is an abnormal resonance phenomenon in the vibration audio signal. The vibration simulation mechanism further includes a patch-type audio collector, which is electrically connected with the vibration audio analysis device. The patch-type audio collector is attached on the mechanism body containing the peripheral interface device. The vibration audio signal is collected by the patch-type audio collector.

According to one embodiment, a structure evaluation system of the embodiments includes a plurality of sensors, an arrival time determiner, a reliability calculator, and a map generator. The plurality of sensors detect elastic waves. The arrival time determiner determines arrival times of the elastic waves using elastic waves detected by the plurality of respective sensors. The reliability calculator calculates reliabilities related to measurement waveforms of the elastic waves on the basis of the arrival times. The map generator generates a first map on the basis of the calculated reliabilities or the reliabilities and a distance.

A device for measuring and protecting a horizontal slide table displacement, comprising: a displacement detected assembly, a displacement detection assembly and a vibration controller, wherein the displacement detected assembly vibrates synchronously with a horizontal slide table top, the displacement detection assembly is configured to measure a displacement value of the displacement detected assembly and transmit the displacement value to the vibration controller, and the vibration controller is used to control the horizontal slide table to vibrate or stop vibrating. The device can achieve the limitation and protection of the horizontal slide table displacement and the device may be flexibly mounted on the horizontal slide table, and has characteristics such as convenient installation and simple use.

The present invention proposes a parameter that appropriately characterizes non-Gaussianity in a random vibration test and realizes vibration control using the parameter. A vibration control system calculates a KRS of a response waveform. The system compares a reference KRS as a target and the response KRS, and controls a characteristic of a phase used to generate a waveform for control such that the response KRS becomes equal to the reference KRS. Upon generation of the waveform for control, the waveform for control is generated by applying an appropriate random phase to each frequency component of an amplitude corresponding to PSD for control. The system controls a characteristic of this random phase (for example, standard deviation of phase distribution, or the like) per frequency, and controls the KRS of the waveform for control. The system deforms the waveform for control on the basis of an equalization characteristic, for which a transfer function of the system is taken into consideration, and calculates a drive waveform. The system sequentially updates the equalization characteristic on the basis of the response waveform and the drive waveform. The calculated drive waveform is converted into a drive signal by a D/A convertor 26, is amplified by an amplifier 28, and is provided to a vibration generator 2.

A method for monitoring the status of an apparatus, wherein an analog signal is converted into a digital signal with an analog-digital converter operating within a measuring range, signal portions of the analog signal extending beyond the measuring range are cut in the digital signal, a spectral analysis is applied to the digital signal to determine which frequency potions the analog signal possesses in a frequency spectrum and conclude a malfunction of the apparatus when the analog signal exceeds the measuring range, where when the analog signal extending beyond the measuring range is in the digital signal, this event is detected and determined as a number, where a signal quality is provided which is used to assess whether known damage frequencies can still be identified from determined frequency portions of the frequency spectrum, although additional overcontrol portions in the frequency spectrum occur as a result of possibly cut signal portions.

A device for detecting whether a plurality of electronic components having one or more defective electronic components includes: an energy source generating energy and transferring the generated energy to the plurality of electronic components in a non-contact manner to cause the plurality of electronic components to vibrate; a mechanical resonance detector detecting vibration resonances of the plurality of electronic components; and a post-processing processor comparing the detected vibration resonances of the plurality of electronic components with a reference vibration resonance of a normal product to determine whether the plurality of electronic components have one or more defective electronic components and then extracting determined information.

The invention relates to a bridge exciter for inducing vibrations in railway or roadway bridges, which comprises a servo-hydraulic actuator connected to a wagon designed to transport the same over tracks or a road. The actuator generates a force by moving a variable-weight reaction mass guided by linear bearings. It comprises hydraulic equipment that enables direct transmission of the vibrations to the infrastructure, independent of the rolling gear of the wagon or the rubber-tired vehicle, via false wheels. The movement of the actuator piston is controlled by a computer allowing the actuator to apply general forces on a bridge or roadway that do not exceed the maximum acceptable displacement of the piston: harmonic, impulsive, and transient forces. The equipment is provided with the necessary load control elements.