A surface wave prospecting method for jointly extracting Rayleigh wave frequency dispersion characteristics in a seismoelectric field. A surface wave prospecting method includes following steps of: acquiring jointly acquired data, where the jointly acquired data includes seismic wave data and electric field data; carrying out jointly imaging processing on jointly acquired data to obtain a superposed frequency dispersion spectrum; carrying out extraction processing on superposed frequency dispersion spectrum to obtain a frequency dispersion curve, outperforming inversion processing on frequency dispersion curve to obtain a stratum structure profile. As seismic wave data and electric field data are adopted to carry out combined imaging processing to obtain superposed frequency dispersion spectrum, multi-mode frequency dispersion curve is extracted, multiplicity of solutions of inversion is greatly reduced during inversion, precision and stability of surface wave prospecting are greatly improved.

A method for monitoring precipitation of magnetospheric particles includes detecting charged magnetospheric particles by a particles detector, processing the detection data to associate a respective estimate or measurement of kinetic energy with the detected magnetospheric particles, obtaining a first count value N.sub.H associated with a relatively higher estimate or measurement of kinetic energy, obtaining a second count value N.sub.L associated with a relatively lower estimate or measurement of kinetic energy, detecting a relative variation of the second count value N.sub.L with respect to the first count value N.sub.H, determining that an impulsive event of precipitation of charged magnetospheric particles (MPP event) in the magnetosphere occurred, assigning to the MPP event geomagnetic longitude and time, defining one or more groups of MPP events occurred in a time range at a same geomagnetic longitude, and identifying a group of MPP events indicative of an activity of terrestrial origin.

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 method of locating a coal-rock main fracture by an electromagnetic radiation from a precursor of a coal-rock dynamic disaster is provided. At least four groups of three-component electromagnetic sensors are arranged in the underground tunnels, and each group of sensors includes three directive antennas for receiving electromagnetic signals orthogonal to each other. The electromagnetic signals are collected by a monitoring host. The signals are ensured to be received by different sensors synchronously via an atomic clock. The direction of the magnetic field line is determined by performing a vector superposition on strengths of the three-component electromagnetic signals of each group of sensors. The planes of electromagnetic wave propagation perpendicular to the direction of the magnetic field line are determined accordingly. The location of the coal-rock fracture is determined by the intersection point of the planes of electromagnetic wave propagation determined by the multiple groups of sensors.

The present invention relates to the technical field of long-term in-situ monitoring of sediment disturbance in deep-sea surface mineral mining, and more particularly to a device for monitoring deep-sea sediment environment in mining polymetallic nodules. The monitoring system comprises: acoustic Doppler flow profilers, a spontaneous potential probe, a turbidity meter and an underwater camera. The invention can realize long-term in-situ observation of sediment disturbance, and can realize the mechanical recovery of probe rod-type equipment without large-scale mechanical devices, thereby reducing the overall weight of the recovery equipment and increasing the probability of successful equipment recovery. Compared with the existing long-term in-situ observation equipment on the seabed, it is more environmentally friendly, efficient, energy-saving and reliable.

Naturally-occurring, electromagnetic signals generated by interaction of solar wind with earth's magnetosphere adjacent a borehole are measured by an electromagnetic sensor positioned adjacent the borehole in the hydrocarbon-bearing formation. Electromagnetic signals generated within the borehole are measured over a period of time by a borehole sensor positioned within the borehole. The electromagnetic signals change over the period of time due to variations in fluid distributions within the hydrocarbon-bearing formation. Electromagnetic changes to the electromagnetic signals generated within the borehole and to the passive, naturally-occurring electromagnetic signals over the period of time are determined by one or more processors. A computational model of the hydrocarbon-bearing formation is generated based in part on the electromagnetic changes.

A device and method for geo-electric extraction under water layer coverage are provided. The device includes auxiliary tubes, outer casings, main tubes, mud extractors, encapsulated extraction electrodes and a fixing ferrule assembly, where the auxiliary tubes each have one end open and the other end closed; the outer casings each have one end open and the other end detachably connected to a top cover; an inner diameter of each of the outer casings is larger than an outer diameter of each of the auxiliary tubes; an outer diameter of each of the main tubes is smaller than the inner diameter of each of the outer casings; the mud extractors each include an inner rod, an outer rod and a bottom plate; the outer rod is sleeved outside the inner rod; the inner rod has one end provided with a dredging wheel and the other end provided with a handle.

A surface wave prospecting method for jointly extracting Rayleigh wave frequency dispersion characteristics in a seismoelectric field. A surface wave prospecting method includes following steps of: acquiring jointly acquired data, where the jointly acquired data includes seismic wave data and electric field data; carrying out jointly imaging processing on jointly acquired data to obtain a superposed frequency dispersion spectrum; carrying out extraction processing on superposed frequency dispersion spectrum to obtain a frequency dispersion curve, outperforming inversion processing on frequency dispersion curve to obtain a stratum structure profile. As seismic wave data and electric field data are adopted to carry out combined imaging processing to obtain superposed frequency dispersion spectrum, multi-mode frequency dispersion curve is extracted, multiplicity of solutions of inversion is greatly reduced during inversion, precision and stability of surface wave prospecting are greatly improved.

A method for collecting and processing the tensor artificial-source electromagnetic signal data and a device thereof; the method comprising the steps of: step S1: determining an electric field polarization direction in a measuring area, and arranging electromagnetic field sensors according to the electric field polarization direction in the measuring area, step S2: respectively collecting artificial-source electromagnetic field signals and natural-field-source electromagnetic field signals, step S3: respectively Fourier-transforming the collected electromagnetic field signals, thereby obtaining the electromagnetic field values corresponding to the artificial source, and the collected electromagnetic field signals corresponding to n groups of natural sources, step S4: calculating to obtain the underground tensor impedances according to the electromagnetic field values corresponding to the artificial source and the electromagnetic field signals corresponding to n groups of natural sources that are obtained based on the least square method, step S5.

A smart holster system may provide notifications of weapon danger, and may include a holster body with a first sensor. The first sensor may detect removal of the weapon from the holster body and indicate the weapon has been drawn. A second sensor coupled to the holster body may detect a gunshot. An indicator panel may include first, second, and third indicators. The first indicator may activate when the weapon has been drawn or the gunshot has been detected. The second indicator may activate after the weapon has been drawn and until the gunshot is detected or a predetermined amount of time elapses. The third indicator may activate after the gunshot is detected or the predetermined amount of time elapses after the weapon has been drawn. A transmitter may notify a Public Safety Access Point (PSAP) without entering a phone number in response to the third indicator being activated.