A load control device for controlling the amount of power delivered to an electrical load is able to operate in a burst mode to adjust the amount of power delivered to the electrical load to low levels. A heater element is disposed within the steam generation vessel, and an induction heating coil is wound around the periphery of the steam generation vessel for energizing the heater element. In an alternative embodiment, all the grooves of the outer and inner joint members have a skewed groove shape with a skew angle which is less than the regular skew angle of the conventional cross groove joint, and a taper angle is provided to the pairs of grooves of the outer and inner joint members. Frame classification affects acceptancerejection of recognition hypothesis. The sewing needles are adapted for carrying respective ends of thread into and through the overlaid placket patch and fabric part to form first and second parallel lines of stitches in the placket assembly. The storage system releases the area of the logical volume corresponding to the storage level virtual volume accessed by a virtual machine which is specified to be deleted, on the basis of storage level virtual volume conversion information which is managed by the storage system.