The present invention is a method to determine an azimuthal orientation of a borehole seismometer sensor performed by a computing device using a control server having a database and an arithmetic function, the computing device performing a method to determine the azimuthal orientation of a borehole seismometer sensor using long-period surface waves in microseisms, including step S100 in which a data collection unit 100 collects continuous waveform data recorded by a borehole seismometer and a reference seismometer; step S200 in which a frequency band setting unit 200 sets a frequency band to be analyzed in the collected continuous waveform data; step S300 in which a filtering unit 300 performs bandpass filtering on the frequency band to be analyzed; step S400 in which a waveform dividing unit 400 divides seismic waveform into waveform segments with preset time units; step S500 in which a phase shift unit 500 shifts the phase of the divided vertical component waveforms by 90°; step S600 in which a waveform calculation unit 600 combines the divided N′ and E′ component seismic waveforms to calculate horizontal components for rotation angles waveform between 0 and 360° from the N′ orientation; step S700 in which a correlation calculation unit 700 calculates a correlation coefficient between the horizontal and vertical component waveforms; step S800 in which a Rayleigh wave orientation determination unit 800 repeats steps S500 to S700 for each divided time domain; step S900 in which an orientation comparison unit 900 performs steps S400 to S800, respectively, with respect to the borehole seismometer data for which the sensor orientation is to be determined and the reference seismometer data for which the sensor orientation is already known; and step S1000 in which a result calculation unit 1000 averages 0 determined for each time period to calculate a final result.

This is an early identification method for a shallow soil landslide, belonging to the technical field of landslide prevention and control engineering. The present invention accurately determines and identifies a shallow soil landslide in a quantitative manner, improving the early identification efficiency of a landslide and helping to improve the disaster prevention effect.

Disclosed is an early warning method for a shallow soil landslide based on a digital topographic map, belonging to the field of landslide prevention and control engineering. The method is characterized by comprising the following steps: a. connecting a straight line along an upward bulged intermediate point of a contour line of the topographic map as an intermediate line; b. determining an intermediate point; c. constituting a three-point group of a plane curvature; d. taking an arithmetic average of slopes as a slope a of a landslide mass; e. according to the distribution principle of topographic DEM data, assigning all points in each grid with the same values; f. taking an arithmetic average; g. calculating a topographic factor T of a potential landslide mass; h. calculating a rainfall factor R; i. calculating an early warning determination value P of the shallow soil landslide; j. performing early warning according to the early warning determination value P of the shallow soil landslide. The shallow soil landslide can be early warned without a lot of historical observation data of landslide occurrence, and the dangerous landslide mass can be determined in advance, which greatly improves the applicability of disaster prevention and the early warning efficiency.

A rock burst hazard prediction method based on vibration wave energy attenuation characteristics of a mine earthquake cluster is provided. The rock burst hazard prediction method comprehensively considers the static load and dynamic load effects of the vibration waves of the mine earthquake cluster based on vibration wave energy attenuation characteristics of the mine earthquake cluster. The static load strength index and the dynamic load strength index involved in the method have clear physical meanings. A comprehensive prediction index calculation model proposed based on the dynamic and static load superposition principle of rock burst occurrence is clear, and the method has a firm theoretical support as well as strong universality and operability. Meanwhile, the updating and adjustment of weights are rapid and the objective judgment and prediction of the final comprehensive prediction results are efficient, and the high-energy mine earthquake and impact behavior area can be effectively predicted.

A system (100) for monitoring a subterranean structure comprises an array (10) with n acoustic sensors capable of detecting P-waves and/or S-waves from the subterranean structure and a central controller (120) for receiving a signal (X) from the sensors. The system further comprises a lookup table (20) comprising a pre-computed travel time curve (24) expressed as relative arrival times of a signal from a location (L.sub.m) to each of the sensors (1−n); a comparison unit for comparing the received signal (X) with the pre-computed travel time curve (24), and means for raising an alarm if the received signal (X) matches the precomputed travel time curve (24). Preferably, the alarm is raised if a computed semblance value (26, 27) exceeds a predefined threshold. The system may monitor several locations (L.sub.m) in parallel using a fraction of the computer resources and time required by prior art techniques.

A building integrity assessment system includes: an earthquake detector including: a building bottom sensor at a bottom of a building and that detects acceleration and an earthquake early-warning receiver that receives an earthquake early warning; a cloud computer; and sensors disposed at a plurality of positions in the building and that measures an influence of an earthquake on the building at each of the positions and wirelessly transmits measurement results to the cloud computer. The cloud computer estimates and evaluates the integrity of the building based on the measurement results. In response to the building bottom sensor detecting preliminary tremors or the earthquake early-warning receiver receiving the earthquake early warning, the plurality of sensors measures the influence of the earthquake on the building from a time before a major motion arrives at the building to a time after the arrival.

An apparatus and method provides for nondestructive inspection of a generally tubular target structure (such as a wellbore casing) by rolling contact engagement of one or more rolling probe devices with the target structure. Each rolling probe device carries electromagnetic (EM) measurement instrumentation to capture measurement data during rolling contact engagement with the casing. Each rolling probe device may comprise an instrumentation carrier (e.g., a roller or a wheel) having an endless tread surface to engage the target structure, with the EM measurement instrumentation extending along the endless tread surface and being located at or adjacent an exterior of the instrumentation carrier. A plurality of such rolling instrumentation carriers can be mounted at azimuthally spaced positions on a tool body configured for axial movement along a wellbore.

A power control device includes non-volatile memory, a controller, and a logic circuit. The non-volatile memory includes a function of externally outputting a logical state of a bit stored in a specific area as a state hold signal that indicates an ON/OFF state of a device function unit before a power cutoff. The controller controls the ON/OFF state of the device function unit and also writes the ON/OFF state of the device function unit to the specific area of the non-volatile memory. The logic circuit controls power supply to the controller on the basis of a logic level of the state hold signal from the non-volatile memory.

An earthquake sensing module includes an acceleration sensor configured to detect accelerations on a plurality of detection axes, a module control unit configured to control the acceleration sensor, and a module storage unit configured to store state information of the acceleration sensor.

An object, such as a building, provided with a system for preventing damage from earthquakes to the object, said system comprising: a foundation anchored to the ground; guide means mounted on said foundation and on said object arranged to allow relative displacement between the object and the foundation in at least one horizontal direction; at least one actuator arranged to displace said object in said at least one direction relative to said foundation; said at least one actuator being connected to a central processing unit;
said central processing unit being connected to at least one displacement sensor;
said at least one displacement sensor being arranged to detect in real time displacement of said foundation and/or the ground and/or said object and to input in real time data about said displacement to said central processing unit; and
said processing unit being programmed to activate in real time said actuator in dependence on said data in such a manner that said object is displaced relative to said foundation in real time, such that the maximum displacement vector of the object relative to the earth's gravitational field is kept substantially smaller than the maximum displacement vector of said foundation relative to the earth's gravitational field.