Abstract: A method for detecting contraband is provided. The method includes acquiring tomographic image data of a subject at a plurality of frequencies using low frequency electromagnetic tomography, generating a composite image of the subject at each of the plurality of frequencies using the acquired tomographic image data, determining a differentiation parameter for a tissue material at each of the plurality of frequencies, determining a differentiation parameter for a non-tissue material at each of the plurality of frequencies, decomposing the composite images into a tissue image and a non-tissue image using the determined differentiation parameters, wherein the tissue image contains any region of the subject composed of the tissue material and the non-tissue image contains any region of the subject composed of the non-tissue material, and determining whether the non-tissue image contains any non-tissue material.

Abstract: Embodiments of the invention include a security checkpoint system that has a camera configured for obtaining a first photographic image of an individual, a photographic image scanner configured for scanning a second photographic image, and a comparator mechanism for comparing the first photographic image with the second photographic image to ascertain whether the second photographic image is of the individual. Other embodiments include a method for automatedly developing security-related characteristics for an individual.

Abstract: A method for determining a location and characterization of an object using a magnetic gradient tensor measurement of the object is provided. The method includes determining an object magnetic field candidate predicted from one of an object measured magnetic field gradient and an assumed object magnetic moment magnitude, and determining an object vector location and an object vector magnetic moment by combining the object magnetic field candidate with an object measured magnetic field.

Abstract: A method for classifying a substance is provided. The method includes transmitting an electromagnetic signal at the substance, measuring a portion of the electromagnetic signal reflected by the substance, determining a reflection coefficient of the substance using the measured portion of the electromagnetic signal, and outputting a classification of the substance based on the determined reflection coefficient.

Abstract: A method for determining a location and characterization of an object using a magnetic gradient tensor measurement of the object is provided. The method includes determining an object magnetic field candidate predicted from one of an object measured magnetic field gradient and an assumed object magnetic moment magnitude, and determining an object vector location and an object vector magnetic moment by combining the object magnetic field candidate with an object measured magnetic field.