In accordance with methods and systems consistent with the present invention, a lease manager is provided for managing leases between clients and other network services. In one embodiment, the apparatus includes a sheath having a proximal end, a distal end and at least one lumen extending from the proximal end to the distal end. The invention also provides pharmaceutical compositions containing such compounds, processes and intermediates for preparing such compounds and methods of using such compounds to treat pulmonary disorders. A tri-level process is implemented in the layout of the first conductor to ensure that the coil width and spacing are uniform and even, in order for the second conductor to be wound therebetween. Hence, the step exerciser can provide a user with various exercise effects. A prepit position signal is detected from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium, so that a write position control is performed based the detected prepit position signal.