A pressure-preserving conventional triaxial compression loading apparatus of the present invention includes a pressure vessel, an upper piston rod, a lower piston rod, and an annular oil bag assembly. Hollow chambers of the pressure vessel in vertical communication sequentially include an upper chamber, an upper sealed chamber, a confining pressure chamber, a lower sealed chamber, and a lower chamber from top to bottom. The annular oil bag assembly is placed in the confining pressure chamber. When an annular inner chamber of an annular oil bag is filled with medium, an outer wall of the annular oil bag and an inner wall of the confining pressure chamber are attached together. A fidelity specimen is placed in a specimen chamber defined by a lower end surface of the upper piston rod, an upper end surface of the lower piston rod, and an inner wall of the annular oil bag. A variety of measuring sensors are disposed in the annular inner chamber of the annular oil bag. The pressure-preserving conventional triaxial compression loading apparatus of the present invention may accommodate a fidelity specimen, and use the annular oil bag assembly and the upper and lower piston rods to perform a pressure-preserving conventional triaxial loading test on the fidelity specimen, so that test data is more accurate and reliable, to help to study the mechanical behavior of in-situ rock and measure their properties more faithfully.

A device is configured to operate a Heating, Ventilation, and Air Conditioning (HVAC) system. The device is further configured to determine that the speed of a combustion air inducer has exceeded a speed threshold value. The device is further configured to receive an audio signal from a microphone while operating the HVAC system, to identify an audio signature for the combustion air inducer from an audio signature library, and to determine the audio signature for the combustion air inducer is present within the audio signal. The device is further configured to determine a fault type based on the determination that the audio signature for the combustion air inducer is present within the audio signal, to identify a component identifier for a component of the HVAC system that is associated with fault type, and to output a recommendation identifying the component identifier.

A device is configured to operate a Heating, Ventilation, and Air Conditioning (HVAC) system. The device is further configured to determine that the speed of a combustion air inducer has exceeded a speed threshold value. The device is further configured to receive an audio signal from a microphone while operating the HVAC system, to identify an audio signature for the combustion air inducer from an audio signature library, and to determine the audio signature for the combustion air inducer is present within the audio signal. The device is further configured to determine a fault type based on the determination that the audio signature for the combustion air inducer is present within the audio signal, to identify a component identifier for a component of the HVAC system that is associated with fault type, and to output a recommendation identifying the component identifier.

Provided are a waveform analysis method and a waveform analysis device capable of preventing, in advance, a breakage accident during operation and preventing stoppage due to breakdown of machinery and performing efficient maintenance work by specifying a degraded part from among the parts that constitute the machinery. A waveform analysis device 30 is provided with; a signal analysis unit 31 for performing fast Fourier transform for a signal transmitted from a sensor 28 that detects a physical phenomenon in the machinery an impulse extraction unit 32 for extracting an impulse component from spectrum data generated by the signal analysis unit 31; a display unit 35 for displaying waveform data including the impulse component extracted by the impulse extraction unit 32; and a data editing unit 33 for editing, from data of a waveform including the impulse component displayed by the display unit 35, waveform data in a range selected via an input unit 36 by a worker, generating a graph displaying a frequency, a time, and the intensity of the impulse component, and displaying the graph on the display unit 35.

Provided are a waveform analysis method and a waveform analysis device capable of preventing, in advance, a breakage accident during operation and preventing stoppage due to breakdown of machinery and performing efficient maintenance work by specifying a degraded part from among the parts that constitute the machinery. A waveform analysis device 30 is provided with; a signal analysis unit 31 for performing fast Fourier transform for a signal transmitted from a sensor 28 that detects a physical phenomenon in the machinery an impulse extraction unit 32 for extracting an impulse component from spectrum data generated by the signal analysis unit 31; a display unit 35 for displaying waveform data including the impulse component extracted by the impulse extraction unit 32; and a data editing unit 33 for editing, from data of a waveform including the impulse component displayed by the display unit 35, waveform data in a range selected via an input unit 36 by a worker, generating a graph displaying a frequency, a time, and the intensity of the impulse component, and displaying the graph on the display unit 35.

An apparatus for detecting a transient event in an operating machine, the apparatus comprising: a controller configured to control performance of the following steps: a measurement step comprising measuring a periodic signal from a machine; a processing step comprising synchronously processing the periodic signal to track the primary frequency; a filtering step comprising removing the primary periodic component and its harmonics from the periodic signal to yield a filtered dataset; an integration step comprising integrating the filtered dataset over the remaining frequencies to yield an integrated dataset representing the periodic energy at frequencies other than the primary frequency and its harmonics; an analysis step comprising identifying a short-term transient in the integrated dataset to identify a transient disruption in the operation of the machine.

An apparatus for detecting a transient event in an operating machine, the apparatus comprising: a controller configured to control performance of the following steps: a measurement step comprising measuring a periodic signal from a machine; a processing step comprising synchronously processing the periodic signal to track the primary frequency; a filtering step comprising removing the primary periodic component and its harmonics from the periodic signal to yield a filtered dataset; an integration step comprising integrating the filtered dataset over the remaining frequencies to yield an integrated dataset representing the periodic energy at frequencies other than the primary frequency and its harmonics; an analysis step comprising identifying a short-term transient in the integrated dataset to identify a transient disruption in the operation of the machine.

According to one embodiment, a sensor includes a first structure body, a second structure body, and a detector. The first structure body includes a supporter, a deformable part supported by a first portion of the supporter, and a membrane part. At least a portion of the membrane part is connected to the deformable part and a second portion of the supporter. The second structure body is connected to the first structure body. A liquid is provided between the first structure body and the second structure body. The detector outputs a signal corresponding to a deformation of the deformable part.

According to one embodiment, a sensor includes a first structure body, a second structure body, and a detector. The first structure body includes a supporter, a deformable part supported by a first portion of the supporter, and a membrane part. At least a portion of the membrane part is connected to the deformable part and a second portion of the supporter. The second structure body is connected to the first structure body. A liquid is provided between the first structure body and the second structure body. The detector outputs a signal corresponding to a deformation of the deformable part.

Data retrieval, event recording and transmission module connectable to safety and relief valves. The module (10) coupled to safety or relief valves for the measurement, transmission and recording of events and includes a rigid and inextensible at room temperature longitudinal element defining an acoustic emission waveguide (12) that transmits vibrations. The end (12a) of (12) is in intimate contact with a portion (2) or (1) of the valve, and its other end (12b) penetrates inside a closed resistant box (10), wherein it sits in contact against at least one acoustic emission sensor (13) receiving a signal proportional to the vibrations transmitted by the waveguide (12).