Agricultural systems have increased in complexity to allow farmers to control the environmental factors impacting a crop. By analyzing data from a plurality, and preferably a large number, of operations, a particular objective for a particular plan may be developed for a particular crop. The equipment at a particular site may then monitor the crop and be controlled by a device, such as an on-site hub, to operate equipment in a manner associated with the particular plan and objective.

A computer-implemented method includes receiving, in computer memory, a first test data set that comprises results of a real-world test of a material, where the first test data set comprises a plurality of test data points. The method further includes identifying one or more critical points among the test data points in the first test data set and processing the first test data set with a computer processor to produce a second test data set with differing (e.g., fewer) test data points than the first test data set, wherein the second test data set includes all the test data points that were identified as critical points in the first test data set and at least some other data points.

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.

This application relates to an apparatus and method for detecting a microcrack using orthogonality analysis of a mode shape vector and a principal plane in a resonance point. The apparatus may include a measurement unit comprising multiple sensors and configured to measure whether a crack exists at a measurement target, and an analysis unit configured to determine whether a crack exists, on the basis of measurement values of the respective sensors. The measurement unit includes a fixing jig configured to fix the measurement target, an excitation means configured to apply a predetermined impact to the measurement target, and multiple acceleration sensors attached at predetermined locations on the measurement target. The analysis unit may further calculate frequency responses of the measurement target to the impact applied by the excitation means, and determine whether a crack exists by analyzing the number of resonance points and independence of the resonance points.

Analysis of residual stress in materials is often done in static conditions in a laboratory. Accurate systems and methods for performing these analyses in a dynamic, non-laboratory environment are notoriously difficult and can be very inaccurate. A method using a portable, field deployable apparatus having greater accuracy than currently available is disclosed whereby accurate and repeatable residual stress analysis may be implemented in non-laboratory environments leading to greatly improved diagnostics, maintenance and life limit prediction.

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 split-type device for measuring rock mass deformation under high hydraulic pressure and a construction method and use thereof. Main components of the device include a metal measuring rod, a magnetic iron core, a shell, a waterproof coil framework, a coil, a tail accessory, a cable clamp, a cable, a signal processing bin, etc. Main electronic components are treated by adopting the all-metal shell and a vacuum particle sealing double-layer sealing process, and have hydraulic pressure resistance of 5 MPa or above. Measurement signals feature centralized processing, digitization and dual utilization of signals, i.e., after data of a plurality of sensors is processed in an electronic bin and then digitized signals are connected to an independent reader outside the bin or a centralized acquisition device for in-situ tests.

A sensor for measuring the fatigue life of a structure subjected to repetitive loads is disclosed. The sensor includes a backing material arranged for securement to the structure, and a foil arranged for securement to the backing material. The foil includes a conductive path along which electrical current flows at an initial resistance measured prior to the structure being subjected to repetitive loads. A crack initiation feature in the form of a notch is located on the conductive path. In response to repetitive loads applied to the structure, one or more cracks propagate from the crack initiation feature across the conductive path to cause electrical resistance to increase whereby the progression of fatiguing of the structure may be determined.

Disclosed is a real-time nondestructive observation and two-phase seepage test system for a fracture of an in-situ fractured gas-bearing reservoir, which comprises a stress loading system, a high-voltage electric pulse fracturing operation system, a water-gas two-phase seepage system and an in-situ CT scanning system; the stress loading system comprises a pressure chamber, an axial pressure loading module and a confining pressure loading module; the high-voltage electric pulse fracturing operation system comprises a high-voltage electric pulse generation module, a high-voltage electric pulse signal monitoring module and a protection module; the water-gas two-phase seepage system comprises a water-gas pressure loading module and a flow data acquisition module; and the in-situ CT scanning system comprises a radiation source, a flat panel detector and a CT scanning detection mechanism.

The present invention relates to a device for measuring residual stress and hardness. Residual stress remaining in a metallic material due to deformation, thermal stress, or the like is a cause of various problems including degradation of mechanical properties such as fatigue strength and fracture properties and difficulty in post-processing. It is very difficult to derive a calibration curve when measuring stress by an existing non-destructive Barkhausen noise measurement method. When cross points of Barkhausen noise measurements for three or more stresses are not at one position, calibrated curves can be easily found by scaling the Barkhausen noise measurements by using calibration equations of the present invention to collect the cross points at a unique position, thereby providing a practical method of easily measuring stress of a metal by a Barkhausen noise measurement method. Therefore, according to the present invention, it is found that the internal microstructure and surface residual stress of a metal cause crossing points not to be at a unique position in a conventional Barkhausen noise measurement experiment. In addition, basic physical properties and surface residual stress of a metallic material may be measured using the above-mentioned physical feature.