Abstract: In a method of operating a system for announcing the presence of one or more individuals on or near a pathway to an operator of a vehicle traveling on the pathway, each of a number of data readers positioned along the pathway receives data input by the one or more individuals. In response to each data reader receiving the data input, a unique subset of a number of lamps, also positioned along the pathway, is caused to illuminate. The system includes a computer network that controls the operation of the lamps in response to the input of data.

Abstract: A safety system for providing early warning notifications to an authorized track worker performing official duties along a rail road network is disclosed herein. The safety system determines the position of the authorized worker and determines an estimated time to collision between the authorized track worker and an approaching rail vehicle. The result of the safety system is that the track worker has enough time and sufficiently accurate warning that will enable the track worker to move to a point of safety so as to remain unharmed by the approaching rail vehicle.

Abstract: In a method of operating a system for announcing the presence of one or more individuals on or near a pathway to an operator of a vehicle traveling on the pathway, each of a number of data readers positioned along the pathway receives data input by the one or more individuals. In response to each data reader receiving the data input, a unique subset of a number of lamps, also positioned along the pathway, is caused to illuminate. The system includes a computer network that controls the operation of the lamps in response to the input of data.

Abstract: A safety system for providing early warning notifications to an authorized track worker performing official duties along a rail road network is disclosed herein. The safety system determines the position of the authorized worker and determines an estimated time to collision between the authorized track worker and an approaching rail vehicle. The result of the safety system is that the track worker has enough time and sufficiently accurate warning that will enable the track worker to move to a point of safety so as to remain unharmed by the approaching rail vehicle.

Abstract: An internal shoe-drum type brake has a pair of shoes separable by an actuator into braking engagement with a brake drum. An automatic adjuster includes a two-part strut extending between the shoes, the first strut part being pivotally mounted on the second strut part and cooperating with the latter via teeth on the second part, such that the first strut part is separated from the teeth when excessive shoe separation occurs upon brake actuation and is moved angularly to a new position of adjustment upon brake release. The first strut part is provided with a number of peripheral projections engagable by an external tool to disengage the first part from the teeth of the second part when it is desired to de-adjust the adjuster in order to facilitate drum removal.

Abstract: A dynamic random-access memory (DRAM) has a first refresh circuit for producing memory refreshes during power-up, and a second refresh circuit for producing memory refreshes during power-down. The power-down refresh circuit is powered by a battery, and has a lower power consumption than the power-up circuit. During transition from power-down to power-up, the frequency of refreshing is doubled for a short period, so as to build up a surplus of refreshes. This allows refreshing to stop while the first or power-up refresh circuit is brought back into operation.