Abstract: An action control point master gatekeeper for a communications network creates a hierarchical scalable signaling and transaction infrastructure for supporting carrier level deployment of, for example, IP telephony using H.323 terminals and gateways. The action control point master gatekeeper supports a plurality of H.323 zones in an administrative domain. Action control point master gatekeepers in an administrative domain can signal to other administrative domains via a hierarchical signaling infrastructure. A backup master gatekeeper can also be present in an action control point. A customer database, which can be distributed within zones or centralized within an administrative domain, allows for address resolution between a terminal alias and a terminal address. The customer database can also contain pointers to special purpose processes, such as network control points, to implement service specific transaction services.

Abstract: A resource management mechanism is provided to ensure that real-time application programs running on a single machine or set of machines exhibit predictable behavior. The resource management mechanism employs the abstraction of an activity which serves as the basis for granting resource reservations and for accounting. An activity submits a request for resources in specified amounts to a resource planner. The activity is resource self-aware so that it is aware of its resource requirements. The activity may query resource providers to obtain resource requirements for particular operations. The resource planner determines whether the activity should be granted the requested reservation by employing an internal policy. Policy is separated by mechanism so that the resource planner may implement any of a number of policies. The resource planner may choose to grant the reservation to an activity or deny the request by an activity.

Abstract: The present invention provides predictable scheduling of programs using a repeating precomputed schedule. In a preferred embodiment, a scheduler accesses an activity scheduling graph. The activity scheduling graph is comprised of nodes each representing a recurring execution interval, and has one root, one or more leaves, and at least one path from the root to each leaf. Each node is on at least one path from the root to a leaf, and the number of times the execution interval represented by each node occurs during the traversal of the graph is equal to the number of paths from the root to a leaf that the node is on. Each node has associated with it an execution interval length, and is adapted to being dedicated to executing the threads of a single activity. The scheduler first selects a current node within the accessed scheduling graph.

Abstract: A resource management mechanism is provided to ensure that real-time application programs running on a single machine or set of machines exhibit predictable behavior. The resource management mechanism employs the abstraction of an activity which serves as the basis for granting resource reservations and for accounting. An activity submits a request for resources in specified amounts to a resource planner. The activity is resource self-aware so that it is aware of its resource requirements. The activity may query resource providers to obtain resource requirements for particular operations. The resource planner determines whether the activity should be granted the requested reservation by employing an internal policy. Policy is separated by mechanism so that the resource planner may implement any of a number of policies. The resource planner may choose to grant the reservation to an activity or deny the request by an activity.

Abstract: A piston ventilator is disclosed herein which uniquely includes an oxygen blending module which supplies oxygen enhancement for aiding patients requiring respiratory treatment. The oxygen blending module supplies a preselected enrichment of oxygen to a piston and cylinder assembly wherein the amount of oxygen permitted to flow therein is continuously monitored and controlled according to the volume above the piston in the cylinder as calculated by a controller. The oxygen blending module includes a flow sensor which monitors the flow of supplemental oxygen into the piston and cylinder assembly, and further includes a primary oxygen control valve which restricts the flow of oxygen through the flow sensor to the piston and cylinder assembly depending on the difference between the calculated desired amount of oxygen and the target amount of oxygen provided to the controller.

Abstract: A method and system for scheduling the use of a computer system resource using a resource planner and a resource provider is provided. In a preferred embodiment, a resource is scheduled for use by a plurality of consumer entities. Each consumer entity may request the commitment of a share of the resource. The method and system utilizes representations of resource usage policy, present commitments of shares of the resource, and present commitments of specified amounts of the resource over specified period of time. The method and system first receives a request from a consumer entity for the commitment of a specified share of the resource. In response, the method and system determines whether the specified share of the resource should be committed to the requesting consumer entity. This determination is based on the representations of resource usage policy and present commitments of shares of the resource.

Abstract: A piston ventilator is provided which advantageously monitors the positive end expiratory pressure (PEEP) in a patient circuit for supplying breathable gas to a patient, and controls a shiftable valve element in an exhalation valve to regulate the amount of resistance during the exhalation portion of the patient's breath. The shiftable element is preferably an inflatable diaphragm which receives a pneumatic signal through a signal conduit. The pressure provided by the signal conduit is controlled by the amount of gas vented by a PEEP valve, wherein the greater the opening of the PEEP valve, the greater the amount of gas from the patient circuit is vented therethrough and consequently the less the restriction is provided in the exhalation valve.

Abstract: A method and system for scheduling the execution of threads using optional time-specific constraints is provided. In a preferred embodiment, a scheduler schedules the execution of a plurality of threads each specifying either a percentage processor time scheduling constraint, indicating that a certain percentage of processor time should be dedicated to the execution of the thread, or a deadline scheduling constraint, indicating that a specified quantity of work should be done by the thread by a specified time deadline. For each thread specifying a percentage processor time scheduling constraint, the scheduler determines a restart time corresponding to the percentage processor time scheduling constraint. For each thread specifying a deadline scheduling constraint, the scheduler determines a restart time corresponding to the deadline scheduling constraint. The scheduler then utilizes the determined restart times for scheduling the threads by selecting the thread having the earliest restart time for execution.

Abstract: A hand control attachment apparatus, for attaching a hand control member to a steering wheel or the like. A web is extended from a housing of the hand control attachment apparatus. The web member cooperates with an outer surface of the housing so as to secure the hand control attachment apparatus onto the steering wheel or the like. A first end of the web member is secured in a slot of a rotatable bar member which is received in the housing. A second end of the web member loops around a rod which is removably received in the housing. The web member is wound onto the bar member by rotating the bar member so as to tightly secure the hand control attachment apparatus onto the steering wheel or the like. The apparatus is released from the steering wheel by releasing the web member and removing the rod out of the looped end of the web member and the housing. The hand control member is mounted on the housing of the hand control attachment apparatus by a spring member, so as to form a hand control device.

Abstract: A scalable method and system for easily scheduling data transfer for a video-on-demand server system is provided. A strategy for locating available bandwidth and allocating available bandwidth to subscribers as needed is provided. The input/output bandwidth of storage devices that store data for video image sequences is modelled as a series of bandwidth units. Each bandwidth unit has sufficient capacity to service an individual subscriber during a scheduling cycle. Video image sequences or other data sequences are striped across storage devices such that data for a data sequence is forwarded to the subscriber by reading from a sequence of storage devices in consecutive time frames.