Abstract: The present ATM switch includes a plurality of controllers, each of which contains a plurality of cell buffers to store cells for each VC. A plurality of arbitration buffers store pointers, on a VC priority level basis, to order the processing of cell transmissions. The arbitration buffers are processed in priority order, with an interrupt being generated by a timer associated with each arbitration buffer, other than the highest priority arbitration buffer, to ensure that each arbitration buffer is periodically processed.

Abstract: The optical servo system for a tape drive that functions to align a read/write head with the data tracks written on a recording surface of a tape by reading optical servo tracks that are formed on the back side of the tape. This process decouples the magnetic recording of data on the recording surface of the tape from the optical servo system which makes use of servo tracks formed on the back side of the tape. The data storage capacity of the tape is increased since the entire recording surface of the tape is filled with data tracks and the precise alignment of the read/write head makes it possible to place the data tracks closer together. Regions of contrasting reflectivity or phase are also provided on a surface of the read/write head to enable the optical servo system to view an image of both the read/write head and the entire back side of the tape to thereby align the movable read/write head with the data tracks.

Abstract: The present data file storage management system for snapshot copy operations maintains a two level mapping table which enables the data files to be copied using the snapshot copy process and only having to update a single corresponding mapping table entry when the physical location of the data file is changed. The snapshot copy updates to the contents of the first level of the two level mapping table are stored on the backend data storage devices to provide a record of the snapshot copy operation which can be used to recover the correct contents of the mapping table. This record of the snapshot copy operations remains valid even though the physical location of a copied data file instance is subsequently changed. Furthermore, the physical storage space holding the updated portions of the first level of the two level mapping table can be managed using techniques like those used to manage the physical storage space holding data file instances.

Abstract: A method for manufacturing a heat-sealed neo-natal medical monitoring probe requires a pair of light sources and a light detector to be placed between two layers or conformable material used to implement the probe. The layers are designed to be self-aligning when placed in the assembly press for heat-sealing the perimeter of the probe. The heat-sealing process both protects the light sources and detector from fluids and also functions to precisely position and secure these devices.

Abstract: The menu selection device uses a combination of the rotary position of a rotary optical encoder and the operation of a coaxially mounted push-button switch to enable the user to progress through various layers of a hierarchical menu system. The rotary position of the shaft translates to a menu category which is selected by the user activating the push-button switch. The selection of the menu category allows the user to then sequence through the plurality of menu entries within this menu category by again rotating the shaft. The user selects one of these menu entries by again activating the push-button switch.

Abstract: This apparatus makes use of the existing data collection probe connector on the instrumentation as the port through which the software updates are loaded into the programmable memory devices that are used to store the operational software of the instrumentation. Circuitry is provided in the instrumentation to automatically differentiate between software update data being loaded into the instrumentation and the normal monitoring data that is received from the probe. This is accomplished by the use of probe defining circuitry that is able to differentiate between the standard probe used for data collection purposes and the software update probe that is provided to download software into the programmable memory devices.

Abstract: The pulsed optical rotary encoder digitally samples the operation of the optical rotary encoder to obtain the same information that is obtained by the use of the continuously active light-emitting devices but in a much more energy-efficient manner. In particular, the light-emitting devices are pulsed into operation for a short duration and at a frequent rate. The signals produced by the light detectors associated with the light-emitting devices are sampled at a predetermined time after firing the light-emitting devices to obtain the data necessary to determine the rotation of the coding disk.

Abstract: The improved pulse oximeter preprocesses the sets of red and infrared signals received from the probe. The set of pairs of processed red and infrared data points are fitted to a linear equation to compute the slope of the best fit line through these data points and account for noise in both of these sets of data points. A measure of the linearity of the input data points, if less than a predetermined threshold, indicates that a distorted signal has been received from the probe. The computed slope of the best fit line is converted to a RRatio which is used in a empirical calibration formula to compute the average SpO.sub.2 value.

Abstract: The twice scaled waveform display apparatus combines a twice scaled factor indication with the autoscaled waveform display so that an input data quality indication is produced based on factors such as signal strength, wherein the twice scaled factor is used to modulate the size of the display that is presented to the user. Thus, the generated waveform occupies a predetermined portion of the display when the signal strength and/or other input data qualities are at an acceptable level. The size of the waveform presented to the user on the display is reduced in magnitude when there is a degradation in the input signal magnitude or other quality factors.

Abstract: The pulse oximeter probe uses an inexpensive connector to electrically interconnect the sensor elements with the pulse oximeter. One segment of the probe connector contains a set of connector pins that are wired to the sensor elements. Another segment of the probe connector is equipped with a mating configuration of sockets which align with these pins. Three projections function to automatically align the connector pins with the connector sockets. Two of the projections engage a mating aperture in the other connector segment to fasten the two connector segments together, while a third projection aligns with an edge of the other connector segment to position the two connector segments.

Abstract: The nasal septum probe of the present invention mounts the optical devices of a photoplethysmographic probe in a housing that clips onto the patient's nasal septum. The septum provides an arterial bed for monitoring purposes and this locus is not subject to significant patient motion or peripheral shutdown of arteriolar blood flow. Furthermore, one embodiment of the invention shows a combination of the photoplethysmographic apparatus with a nasal cannula to provide dual purpose apparatus to minimize the sensor and cable proliferation.

Abstract: This arterial blood monitoring system takes advantage of the basic statistical property that arterial blood contains a plurality of dominant absorbers, whose measured light absorption spectra appear as a constant over a short interval of time. By measuring the transmitted light as it varies with arterial pulsation at selected wavelengths of light, over a common light path, the relative amount of these dominant absorbers in the arterial blood can noninvasively be determined. To ensure the common light path, a sandwich construction light detector is used.

Abstract: The document authentication apparatus provides document authentication and authenticity capability. Document authentication requires that the person to be charged apply an authenticating mark on the document indicating intent to authenticate the document. This requirement is analogous to a signature on a printed document and is implemented in the document authentication apparatus electronically through the use of both hardware and software. A program which immediately checks the identicalness of the document at the transmitting and receiving station through a high speed comparison, locks in the document such that no modification can occur and then awaits authentication handshakes from the two end points. Such authentication is real-time and can be both hardware and software executable, i.e., password and physical confirmation.

Abstract: The fire deterrent system operates in a preemptive manner by detecting the impending approach of a wildfire within the vicinity of the structure to be protected. The system includes apparatus to identify the locus and direction of spread of a fire while it is outside of a defensive perimeter that encircles the structure and extends outward therefrom. The estimated time of arrival of the fire at the defensive perimeter is determined and the structure and surrounding vegetation sprayed a predetermined time in advance of the determined arrival of the fire. Prewetting the structure and surrounding vegetation reduces the probability of local fires caused by wind-borne embers and reduces the combustibility of these materials to assist conventional fire fighting efforts.

Abstract: The document authentication apparatus provides document authentication and authenticity capability. Document authentication requires that the person to be charged apply an authentication mark on the document indicating intent to authenticate the document. This requirement is analogous to a signature on a printed document and is implemented in the document authentication apparatus electronically through the use of both hardware and software. A program which immediately checks the identicalness of the document at the transmitting and receiving station through a high speed comparison, locks in the document such that no modification can occur and then awaits authentication handshakes from the two end points. Such authentication is real-time and can be both hardware and software executable, i.e., password and physical confirmation.

Abstract: The communication facilities access control arrangement of the telephone munication system detects the dialing of an unauthorized or invalid long distance transmission facility access code and identifies the calling station. A record is maintained of all invalid attempts to access the long distance facilities. When the number of invalid attempts by a calling station exceeds a predetermined limit, the telephone communication system restricts the calling station from all further long distance transmission facility access and generates an alarm indication to identify a possible facility access problem.

Abstract: The subject implied principal busy status indicator provides all covering users with an indication of the busy/idle status of the principal's line on a covered call. This is accomplished by equipping each covering user's telephone station set with a principal busy status indicator for every line appearance on the covering user's telephone station set. When a covered call is diverted from a principal's line to the covering user's telephone station set, the line appearance on which the covered call appears is lighted and the principal busy status indicator associated with the covering user's line appearance indicates the busy/idle status of the principal's line. The business communication system updates the state of the principal busy status indicator so the covering user knows when the called principal's line is idle.

Abstract: A dial tone detection arrangement for a PBX which provides a dial tone detection notification feature to a calling party is disclosed. The disclosed arrangement relieves the calling party from the burden of aurally monitoring the receiver of a station while waiting for receipt of central office (C.O.) dial tone. The dial tone detection notification feature is advantageous under conditions where the calling party places a call to a called station served by the C.O. and experiences extensive delays, e.g. 30 minutes, in the receipt of C.O. dial tone. The dial tone detection arrangement utilizes an algorithm to establish a connection between a dial tone detection circuit of the PBX and a trunk port connected to a C.O. via a switching network. The dial tone detection circuit monitors the C.O. via the trunk port for the presence of dial tone indicative of C.O. availability. The calling party may now go "on-hook" and await a notification at the calling station indicative of the detection of dial tone.

Abstract: The subject wideband switching network provides inexpensive point-to-point wideband communication connections. Wideband source and destination terminal equipment are either connected to modems which encode the analog signals used by the wideband source terminal equipment into digital signals for transmission through the wideband switching network and decode the received digital signals into analog signals used by the wideband destination terminal equipment; or are directly connected to the wideband switching network if source and destination terminal equipment transmit and receive digital signals. The modems are connected to the wideband switching network by optical fibers. The wideband switching network is a point-to-point space division switch that is comprised of a matrix of high frequency semiconductor crosspoints.