Abstract: A wireless classroom response system wireless network is located proximate to a classroom, a base station that coordinates the activities of the wireless network, and a plurality of handheld units. Each handheld unit is associated with an attendee of a class (either on a long-term or “owned basis, or on an ad-hoc or “shared” basis). Each handheld unit performs a discovery process that includes the steps of randomly choosing a wireless channel, attempting to discover the presence of the wireless network on the channel, and repeating these two steps if no wireless network is discovered.

Abstract: Access of a malfunctioning server to a data storage facility is blocked. Characteristics such as IAmAlive signals from a server are monitored and when out of profile a malfunction is indicated and data access of that server is inhibited. Characteristics continue to be monitored for a return from the malfunction. The system can be used in a resilient cluster of servers to shut out a malfunctioning server and enable its recovery to be indicated so as to enable readmittance to the cluster.

Abstract: An insert damper for assembly in a tubular drive shaft of a motor vehicle includes a tubular sleeve, a helically wound, resiliently deformable wiper secured to the sleeve, and a corrugated winding secured to the sleeve. The wiper includes an arcuate bead in the form of an arch that spans mutually spaced supports. The insert damper is sized to fit in the bore of the drive shaft such that the bead frictionally engages the surface of the bore and secures the insert in place within the shaft with a resilient press fit. The bead projects radially outward toward the bore beyond the radially outer surface of the winding.

Abstract: Trunking or other relationship is defined between ports on different devices in a cascade-connected stack of network devices. When network communications are passed via the cascade connection an indication is included of whether it originated from a port that is part of a trunk and thereby port-mismatch errors can be avoided.

Abstract: A trie searching technique employs entries each including a pointer to the next block in the search and a status indication and also including start and end indexes which define a selected section of the trie key identifying an entry within the block identified by the pointer. Thereby the program for selection of the search key is defined by the trie entries themselves, enabling a general variety of search selections and jumps to avoid any unnecessary parts of the trie search key.

Abstract: A sub-system for forming part of a packet-data communication system for the transmission of data packets which contain media access control addresses and protocol addresses. The sub-system comprises a multiple-port network switch for forwarding data packets in response to an examination of the packets on the basis of the packets protocol addresses, and for performing said examination when a destination address in the packet corresponds to the media access control address of the switch, the switch being arranged for forwarding a packet on the basis of a media access control address therein when the destination address of the packet does not correspond to the media access control address of the switch, said switch including a forwarding database which comprises entries which relate a protocol address with a media access control address and an identification of a particular port of the switch. This switch may perform routing within a local-area network.

Abstract: A system and method to smoothly limit the top speed of the generator motor at which power is provided. The system according to this invention consists primarily of an engine, which supplies mechanical power to a switched reluctance motor with position sensing capability, which delivers electrical power to an inverter. The inverter contains a digital signal processor (DSP) controller to control the delivery of electrical power to the battery in the generation mode. Signal information regarding motor speed and current is delivered from the switched reluctance motor with position sensing capability to the DSP controller and signal information regarding current and voltage is delivered from the battery to the DSP controller. In the preferred embodiment, the switched reluctance machine will have position sensing capability to monitor the position of the rotor in relation to the stator, and sensors to monitor the phase currents and bus current.

Abstract: The present invention is based on a ring architecture wherein each chip in the multiplicity of chips is connected in a chain so that it can receive packets from the next previous chip in the chain and forward packets to the next following chip in the chain, whereby to form a ring. Before a packet is placed on the ring by a device it is provided with a ‘masking’ field which identifies each of the other devices and the ports within any such device to which the packet must be sent in order to achieve a multicast. When a device in its turn receives such a packet it will examine the masking field to determine whether the field identifies that device. If so, the packet, which may be held in temporary storage, may be processed for forwarding from a port of that device. The device will strip from the masking field the identification of the respective device and transmit the packet with a thus modified masking field to the next device in turn.

Abstract: A network switch including a port for the reception and transmission of data packets, and a receive buffer store connected to the port, detecting a predetermined state of fullness of the buffer store, initiating in response to the state of fullness the production of control frames for signaling to a source of packets to pause the sending of packets to the switch, counting said frames to obtain a measure of congestion of the switch, and responsive to a rate of change of measure to enable the discarding of packets received by the buffer when rate is higher than a first predetermined value and to disable the discarding of packets when the rate of change of the measure is below a second predetermined value.

Abstract: A method and apparatus for blocking access of a malfunctioning server to a data storage facility. Characteristics such as IAmAlive signals from a server are monitored and when out of profile a malfunction is indicated and data access of that server is inhibited. Characteristics continue to be monitored for a return from the malfunction. The system is used in a resilient cluster of servers to shut out a malfunctioning sever and enable its recovery to be indicated so as to enable readmittance to the cluster.

Abstract: A forwarding database in a network switch is established and maintained by performing a look-up for a source address read from an incoming frame to find a match between the source address in the frame and the source address in an entry which includes that source address, a port number and an age field. New entries are made if matches are not found, so that the forwarding database facilitates the dispatch of frames to destination addresses corresponding to source addresses in the table. The switch maintains a system age, such as a two-bit field, which is changed from time to time and the current system age is entered in the table as the age field when a source address entry is made. When said source address is found by a look-up process, it is updated with the current system age only if the age field of the entry and the current system age do not correspond. There is a saving of bandwidth arising from the avoidance of write cycles when an age field of an entry corresponds to the current system age.

Abstract: Trunking or other relationship is defined between ports on different devices in a cascade-connected stack of network devices. When network communications are passed via the cascade connection an indication is included of whether it originated from a port that is part of a trunk and thereby port-mismatch errors can be avoided.

Abstract: Trunking or other relationship is defined between ports on different devices in a cascade connected stack of network devices. When network communications are passed via the cascade connection an indication is included of whether it originated from a port which is part of a trunk and thereby port-mismatch errors can be avoided.

Abstract: A forwarding database in a network switch is established and maintained by performing a look-up for a source address read from an incoming frame to find a match between the source address in the frame and the source address in an entry which includes that source address, a port number and an age field. New entries are made if matches are not found, so that the forwarding database facilitates the dispatch of frames to destination addresses corresponding to source addresses in the table. The performance of a source address look-up is inhibited in the absence of a token, a reservoir of tokens being decremented each time a source address look-up is performed and incremented from time to time, at a selectable rate. The process facilitates the performance of a destination address look-up for every received frame by restricting the bandwidth made available for source address look-ups.

Abstract: A trie searching technique employs entries each including a pointer to the next block in the search and a status indication and also including start and end indexes which define a selected section of the trie key identifying an entry within the block identified by the pointer. Thereby the program for selection of the search key is defined by the trie entries themselves enabling a general variety of search selections and jumps to avoid any unnecessary parts of the trie search key.

Abstract: A stabilized solid oral pharmaceutical composition comprised of iodide and iodate as the active agents in the presence of one or more pharmaceutical excipients and a method for preparing these stabilized compositions.

Abstract: Disclosed is a process for making an .alpha.,.alpha.,.alpha.-trifluoromethoxybenzene by reacting an .alpha.,.alpha.,.alpha.-trichloromethoxybenzene or an .alpha.,.alpha.,.alpha.-tribromomethoxybenzene with gaseous hydrogen fluoride in the presence of a catalyst of antimony pentachloride, molybdenum pentachloride, molybdenum dichloride dioxide, molybdenum oxide, or a mixture thereof. The hydrogen fluoride is used in an amount of about 1 to about 1.4 times stoichiometric and is at about atmospheric pressure. The reaction is performed at about 30 to about 100.degree. C.

Abstract: Disclosed is a method for making high purity .alpha.-chloroxylenes. A composition is formed of about 15 to about 80 wt % of a xylene and about 20 to about 85 wt % of a solvent. The solvent can be toluene, ring halogenated toluene, benzotrichloride, ring halogenated benzotrichloride, benzotrifluoride, ring halogenated benzotrifluoride, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexafluorometaxylene, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexafluoroparaxylene, or a mixture thereof. The composition is heated to about 70 to about 160.degree. C. No base is present in the composition. Chlorine gas is sparged through the composition and chlorine free radicals are generated therein. The chlorine free radicals can be generated either with UV light or by means of a chlorine free radical initiator.

Abstract: Apparatus for monitoring and controlling data flow ina computer network device having a plurality of parts comprises control means for directly linking ports together on the basis of additional information stored in the control means whereby incoming packets are linked directly to an utput port to achieve high performance. The additional information is stored in one more look-up tables additional to the normal CAm with the or each table addressed by separate processing. This allows the implementation to be in hardware rather than in software.

Abstract: Disclosed is a method of preparing an aromatic compound having the general formula ##STR1## where R is CF.sub.3, OCF.sub.3, OC.sub.2 F.sub.5, CN, NCO, or COCl, m is 0, 1, or 2, n is 0, 1, or 2, q is 1 or 2, and q+m+n is an integer from 1 to 5. A vapor is prepared of a substrate having the general formula ##STR2## and a chlorinating agent. The mixture is reacted at a temperature above the boiling point of the substrate but below its decomposition temperature. The amount of chlorinating agent is about 0.5 to about 2 times the amount stoichiometrically required to replace the nitro groups on the substrate with chlorine. Unreacted substrate and partially reacted substrate are condensed from the product mixture and are recycled. The substrate is preferably in contact with the chlorinating agent before it is vaporized.