A security portal includes magnetic field sensors in a sensor assessment network (SAN) for tracking a magnetic dipole target. Each sensor includes a sensor transducer, a sensor coil, and a digitally controlled potentiometer. A sensor controller applies a stepped voltage, samples an output frequency at each stepped voltage value, generates a magnetic sensor response curve, and converts a non-linear response of the sensor transducer to a magnetic field value for each x, y and z channel as a function of frequency for a specific potentiometer setting based upon the sensed magnetic dipole that is tracked in the security portal. A SAN controller receives the magnetic field values from each channel and determines the magnetic field vectors of the target over each sample.

A method for determining an occupancy state of a parking space of a parking facility, including the following method steps: a. detecting magnetic field measured values in the surroundings of the parking space along an axis with the aid of a magnetic field sensor within a predefined duration; b. forming a Poincaré diagram as a function of the magnetic field measured values detected in method step a; c. determining a line of best fit through the points of the Poincaré diagram formed in method step b, with the aid of linear regression; d. determining differences in the vertical direction between the line of best fit and the respective points; e. calculating a mean value of the differences determined in method step d; and f. determining the occupancy state of the parking space as a function of the mean value calculated in method step e.

Disclosed are methods and apparatus for identifying non-metallic subterranean structures using amorphous metal markers associated with the structures. Some examples will include the amorphous metal in the form of one or more sections of an amorphous metal foil within a protective enclosure sufficient to physically isolate the amorphous metal foil from the surrounding Earth. The amorphous metal foil and enclosure may be in the form of a tape which either will be secured to, or placed proximate the subterranean structure, which may be, for example, a pipe or conduit, or other non-metallic structure.

Disclosed are methods for locating deposits of mineral resources below the Earth's crust. A period of resonance of 14-day gravitational tides is predicted based on known information about a location. During the period of resonance, element vapor emissions and/or other data are recorded using gas analyzers and/or other devices, which are spread in an array over the location. The vapors and/or other data are recorded for a period of about 3-4 days. The recorded data is analyzed to determine when and where any anomalies exist. By comparing anomalies to control data, the changes can be further extrapolated to obtain more accurate data. After anomalies are detected and analyzed, the locations of deposits comprising mineral resources can be determined and maps of the locations correlating to the surface are generated.

Disclosed are methods for locating deposits of mineral resources below the Earth's crust. A period of resonance of 14-day gravitational tides is predicted based on known information about a location. During the period of resonance, element vapor emissions and/or other data are recorded using gas analyzers and/or other devices, which are spread in an array over the location. The vapors and/or other data are recorded for a period of about 3-4 days. The recorded data is analyzed to determine when and where any anomalies exist. By comparing anomalies to control data, the changes can be further extrapolated to obtain more accurate data. After anomalies are detected and analyzed, the locations of deposits comprising mineral resources can be determined and maps of the locations correlating to the surface are generated.

A method for locating a buried casing stub may include a) identifying a target region, b) providing at each of a plurality of survey points in the target region a casing stub locator that includes a vector magnetometer, c) measuring the magnetic field at each of the survey points using the vector magnetometer so as to generate a plurality of magnetic field measurements, d) using the magnetic field measurements to generate a model of the magnetic field of the target region, e) fitting the model generated in step d) to a selected model of a magnetic anomaly created by the casing stub so as to generate model fit information (MFI), and f) locating the casing stub using the MFI. At each survey point, an expected Earth magnetic field can be subtracted from the measured magnetic field. A total station can measure the position and/or the azimuth of the package.

The present invention discloses a method and system for processing gravity and magnetic data in geological resource exploration. The method includes: acquiring first (i) potential field data and (ii) gradient data of an observation surface, performing upward continuation of the acquired data using a wave-number domain conversion method to obtain second and third gradient data and second potential field data, and determining third potential field data using a fourth-order explicit scheme Milne method according to the first, second, and third gradient data, and the second potential field data; calculating fourth gradient data using an ISVD method according to the third potential field data; and correcting the third potential field data using a fourth-order implicit scheme Simpson method according to the fourth gradient data, the first potential field data, and the first and second gradient data to obtain corrected third potential field data.

A security screening installation system for use in a controlled environment is described. In an embodiment, a passive detector apparatus does not produce a magnetic field for detection and relies on detecting changes in the local magnetic field. The apparatus is: (i) battery powered; (ii) light enough to be hand carried by hand and set up by one person; (iii) comprises a single elongate housing; and (iv) operable between a packed state inside a protective case and a ready to use state outside of the protective case. The housing supports at least two magnetic sensors that define a gradiometer which is arranged to produce a signal indicative of an ambient magnetic field or gradient over a zone of sensitivity which extends away from the housing, wherein a size of the zone is large enough to contain a whole body of a person.

Utility locators for providing information about hidden or buried pipes or other cavities are disclosed. A locator may be configured to provide positional information associated with the buried utility based on signals received from a line trace signal and a sonde signal and present the positional information on a visual display or other output device.

A system comprising: a magnetic transmitter configured to generate magnetic fields; a magnetic sensor configured to generate signals based on characteristics of the magnetic fields; and one or more computer systems configured to: cause the magnetic transmitter to generate a first plurality of magnetic fields at a first frequency; receive a first plurality of signals from the magnetic sensor; determine data indicative of a position and orientation of the magnetic sensor at a first position of the magnetic sensor; determine a distortion term that corresponds to a first position of the magnetic sensor; cause the magnetic transmitter to generate a third plurality of magnetic fields at the first frequency; receive a third plurality of signals from the magnetic sensor; and determine a second position and orientation of the magnetic sensor relative to the magnetic transmitter, wherein the first frequency is greater than the second frequency.