Abstract: A charging system for installation into a block wall includes a docking unit, a cover unit and a charging unit. The docking unit includes a docking unit hollow body with an open front face, and a back plate closing the rear face and an electrical connector positioned within the docking unit hollow body. The cover unit includes a cover unit hollow body for insertion into the docking unit hollow body. The charging unit has a charging unit hollow body for insertion into the docking unit hollow body; and a charger module is located in the charger housing and the charging module includes contacts for connecting to the docking unit electrical connector, and a cable connector for connecting a charging cable.

Abstract: Apparatus and method useful in temperature control system for a predetermined area that employs a user friendly electronic thermostat that can be programmed intuitively and which is impossible to incorrectly program. Further, the electronic thermostat needs no periodic maintenance checks because it employs a super capacitor to supply electrical energy to memory if power is temporarily lost. A large display means is responsive to the operator's programming as the programming is being performed, in addition to other times.

Abstract: A method and apparatus is provided for measuring the timing jitter of a tributary data stream that has been multiplexed into a higher-rate multiplex stream using pulse stuffing techniques. The required jitter measurement is carried out by monitoring the relevant stuffing control bits of the multiplex stream. In one embodiment, the apparatus comprises a first microprocessor for determining the tributary stuffing ratio from the stuffing control bits, and a second microprocessor operative to determine a current jitter signal value by using both the stuff information contained in the stuffing control bits, and the stuffing ratio determined by the first microprocessor. The second microprocessor carried out its task by updating a preceding jitter signal value by incrementing this value each time a stuff occurs while decreasing the jitter signal value at a rate dependent on the stuffing ratio. Preferred algorithms are disclosed for determining both the stuffing ratio and current jitter signal value.

Abstract: A tundish for continuous casting of molten metal having an outer metal casing and, adjacent the casing, a permanent refractory lining is provided with an inner, expendable lining comprising refractory, heat-insulating slabs having an erosion resistant backing layer and an inward facing layer of lower density than that of the backing layer.The density of the facing layer is at least 0.2 g/cm.sup.3 but not more than 85% of the density of the backing layer. The presence of the inward facing layer exerts less chilling effect on the molten metal poured into the tundish than if the slab consisted of the backing layer alone.