Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for monitoring events using a Virtual Inductive Loop system. In some implementations, image data is obtained from cameras. A region depicted in the obtained image data is identified, the region comprising lines spaced by a distance that satisfies a distance threshold. For each line included in the region: an object depicted crossing the line is determined whether to satisfy a height criteria indicating that the line is activated. In response to determining that an object depicted crossing the line satisfies the height criteria, an event is determined to have likely occurred using data indicating (i) which lines of the lines were activated and (ii) an order in which each of the lines were activated. In response to determining that an event likely occurred, actions are performed using at least some of the data.

Abstract: An electrical penetrator assembly for conveying electrical wires through a wall which separates a hostile environment from an adjacent environment suitable for access by human operators. The assembly comprises a unique modular construction formed by a plurality of lead disks each having at least one aperture of axial direction and location appropriate to form a continuous spiraling passageway that is skewed with respect to the axis of the penetrator along at least portions thereof to substantially reduce or eliminate inadvertent escape of the hostile environment through the assembly. The assembly also comprises a positionable connector platform on which connector assemblies provide suitable interconnecting pin structure to mate wires contained within the penetrator to interconnecting cables within the hostile environment.