Abstract: A method for generating an approximate answer to a query in a database environment in which the database has a plurality of base relations. A query relating to a database is received, and an approximate answer to the query is generated such that the approximate answer is based on at least one join synopsis formed from the database. The method further includes steps of forming a sample-tuple set for at least one selected base relation of a plurality of base relations of a database such that each sample-tuple set contains at least one sample tuple from a corresponding base relation, and forming a join synopsis set for each selected base relation such that each join synopsis set contains a join synopsis for each sample tuple in a sample-tuple set. A join synopsis of a sample tuple is based on a join of the sample tuple and at least one descendent relation of the sample tuple. All join synopsis sets form a statistical summary of the database and are stored.

Abstract: The next generation digital signal processors and reduced instruction set chip processors have multiple arithmetic and logic units and multiply and accumulate units to boost the processor performance. This technique along with higher clock speed of the processors has moved the processor throughput bottle neck to the bus bandwidth. Thus, a bandwidth efficient implementation of standard processing functions is very important to improve the real throughput of these processors. A few processors already use a wide data bus to access multiple consecutive data elements in memory to boost the bus bandwidth. This feature has been used extensively to speed up the cache performance. Disclosed herein is a bandwidth efficient implementation of FIR filter. In any intensive signal processing applications, filters are the basic processing function. The proposed method reduces the required bus bandwidth by about a factor of 2.7 without increasing the number of MAC operations.

Abstract: On instructions obtained from a subscriber, a wireless terminal service provider sends a power-down signal to a wireless terminal. Upon receipt of the power-down signal, the wireless terminal goes into a sleep state. In this state, all monitoring functions other than time, date and elapsed time are turned off. The power-down signal sets a clock, which can be located within the wireless terminal, to awaken the wireless terminal at the end of a discrete interval of time by powering-up the monitoring circuits. The wireless terminal service provider, by knowing the power-down/power-up time cycle of the wireless terminal, can alert a party attempting to contact the wireless terminal during the power-down period that the called party cannot be reached.

Abstract: A vision comparison inspection system is disclosed for use in a printed circuit assembly production line having a plurality of component processing locations and a conveyor system for transporting circuit assemblies between processing locations in an upstream to downstream work flow direction. The vision comparison inspection system includes a printed circuit assembly image capture and inspection conveyor disposed in the production line, the image capture and inspection conveyor being adapted to receive printed circuit assemblies from an upstream portion of the production line and to transport the printed circuit assemblies to a downstream portion of the production line for subsequent processing. An electronic imaging device is fixedly positioned to capture an image of a printed circuit assembly located on the image capture and inspection conveyor. A lighting system is mounted for illuminating a printed circuit assembly located in the field of view of the imaging device.

Abstract: A method for use in a cellular communication system is disclosed which dynamically assigns a communication device to a cell site and which dynamically assigns transmit power levels to the communication device. The method is based on measurements of interference levels at cell sites and on the path gain between the communication device and the cell site.

Abstract: A communications system includes at least one mobile station and a plurality of base stations each transmitting a downlink signal to the at least one mobile station substantially asynchronously from one another. Each base station receives an uplink signal from the at least one mobile station responsive to the downlink signal. Further, each base station has a known position and may determine a round trip delay between transmission of the downlink signal and reception of the uplink signal. The communications system may also include a position determiner for determining a position of the at least one mobile station based upon the round trip delays and the known positions of the base stations.

Abstract: The present invention provides a method and system for sequential pattern mining with a given constraint. A Regular Expression (RE) is used for identifying the family of interesting frequent patterns. A family of methods that enforce the RE constraint to different degrees within the generating and pruning of candidate patterns during the mining process is utilized. This is accomplished by employing different relaxations of the RE constraint in the mining loop. Those sequences which satisfy the given constraint are thus identified most expeditiously.

Abstract: Advantageous error rate performance, high bandwidth efficiency, low delay and reduced error floor are achieved at an acceptable level of decoding complexity via the use of serial concatenated turbo codes. These are codes for which at least some of the output bits, including at least one redundant bit, provided by a first, outer encoder are, after interleaving, further processed by a second, inner encoder. The resulting data and redundant bits then select a symbol from a predetermined constellation for transmission. In the receiver, the turbo code is decoded using a corresponding number of soft output decoders which operates iteratively in such a way that improved performance as compared to a single encoding can be achieved. The turbo codes can be of various dimensionalities and can be used as a component of a multilevel code to achieve a desired level of bandwidth efficiency.

Abstract: Substantially error-free communications is achieved in an optical communication system that includes optical amplifiers by detecting bits transmitted in the amplified optical signal using a detection threshold that is derived as a function of a maximum power level associated with a first bit value, e.g., bit “0”, and a minimum power level associated with a second bit value, e.g., bit “1”. Importantly, this detection scheme can be used to accurately detect bit patterns in the amplified signal even in the presence of nonlinear distortions caused by gain variations, such as inter-modal distortion and saturation induced crosstalk. In a wavelength division multiplexed (WDM) system comprising semiconductor optical amplifiers, for example, the detection threshold can be set at a level corresponding to PTOTAL/2N, where PTOTAL represents the total power in the WDM signal and N represents the number of optical channels in the WDM signal.

Abstract: A protective device for an optical coupling located in an enclosure defined at least in part by spaced first and second planes. The optical coupling is located nearer to the first plane than to the second plane. The protective device includes a closure configured to engage the coupling, and a handle having a first end coupled to the closure to permit manipulation of the closure by manipulation of the handle, and a second end. The length of the device is such that, when the closure engages the coupling, the second end is nearer to the second plane than to the first plane.

Abstract: A method and apparatus are disclosed for providing persistent storage of Web resources. Uniform Resource Locators (“URLs”) that identify Web resources are augmented to include a time stamp. A web browser and a web server are disclosed that accommodate a time stamp parameter and allow a user to refer to any Web address with a precise target date. The disclosed Web browser can optionally include a mechanism to facilitate the specification of the desired date and time, or the user can manually append the time stamp to the URL indicated in the “Location” window of the browser. The persistent Web servers (i) receive URLs containing a time stamp or relative time-stamp, (ii) extract the time stamp, (iii) retrieve the appropriate Web page corresponding to the time-stamp, and (iv) return the appropriate page to the client. The persistent Web servers include a persistent archive for storing all of the versions of Web resources that will be persistently available to Web users.

Abstract: An encapsulated semiconductor device and method wherein an encapsulant material is deposited on the device in an environment that enhances device performance. Illustrative encapsulant materials are organic polymers, silicon polymers and metal/polymer-layered encapsulants. Encapsulant formation environments may include inert, reducing and ammonia gas environment. Further disclosed are an encapsulated transistor and a semiconductor device.

Abstract: An optical fiber cleaner includes a base having a well supported within an annular section. An absorbent material, such as a sponge or cotton ball, may be located within the well of the base. A cover mates with the base and holds a wipe in a preferred position over the well. The cover includes an aperture through which the wipe may be accessed. The cover may also include a hinged element, or lid, that closes over the aperture within the cover when the cleaner is not in use. The base may itself be an element of the lid of a push-pump mechanism. In such case, the well within the base is operationally connected to receive solvents from the pumping mechanism and the pumping mechanism, including the base, forms a cover for a solvent reservoir, such as a non-reactive bottle.

Abstract: In the method for overload control in a wireless communications network employing On-Demand Multiple Access Fair Queuing, if the downlink/uplink buffer occupancy of the network has exceeded a high threshold, the base station determines if this is caused by a specific remote host or by a group of remote hosts. If caused by a specific remote host, the base station normally sends a flow control signal to the remote host to prevent it from sending more data, but may alternatively elect to disconnect other remotes if the remote experiencing bad performance is of a higher priority. The base station may additionally reduce the bandwidth shares allocated to any remote that have indicated tolerance for a variable allocated bandwidth. If the measured frame error rates for many remote hosts are increasing, then the base station may elect to disconnect those remote hosts that permit service interruption in order that more bandwidth may be allocated to the remaining users.

Abstract: A system and method are presented for reducing intermodulation products in a cellular radio system. The cellular radio system constructs and stores modified channel sets that have a reduced measure of homogeneity. The cellular radio system selects a channel number from the appropriate modified channel set in order to support a call. This invention reduces radio interference, thus improving the quality of service and increasing the call capacity of the cellular radio system.

Abstract: Methods and apparatus for hosting a network service on a cluster of servers, each including a primary and a secondary Internet Protocol (IP) address. A common cluster address is assigned as the secondary address to each of the servers in the cluster. The cluster address may be assigned in UNIX-based servers using an ifconfig alias option, and may be a ghost IP address that is not used as a primary address by any server in the cluster. Client requests directed to the cluster address are dispatched such that only one of the servers of the cluster responds to a given client request. The dispatching may use a routing-based technique, in which all client requests directed to the cluster address are routed to a dispatcher connected to the local network of the server cluster. The dispatcher then applies a hash function to the client IP address in order to select one of the servers to process the request.

Abstract: A method and apparatus are disclosed for measuring the usage of a communications network, based on a two level sampling and measuring technique. A sampling interval, T, represents the intervals at which the network resource is observed. In addition, during each sampling interval, a measurement window of length, &tgr;, is utilized. Generally, while the values for the sampling interval, T, and the measurement window, &tgr;, are calibrated, actual measurements are only taken for the smaller measurement window, &tgr;, and the actual measurements are extrapolated to estimate the usage over the larger sampling interval, T. The sampling interval, T, and measurement window, &tgr;, values may be periodically recalibrated.

Abstract: A system for providing location based service telephone call to wireless subscribers. The system of the present invention provides processes for receiving location data about a wireless subscriber telephone and using the information to find the telephone number of the nearest service provider. The wireless subscriber telephone set can then be connected to the nearest service provider. It is also possible to a plurality of different location identifiers to determine the nearest service provider. In performing a look-up, the list can be used on a priority basis to determine the nearest service provider.

Abstract: An optical fiber transmission link with reduced channel depletion due to stimulated Raman scattering is formed by including a high pass optical filter in the transmission fiber. The filter may comprise one or more discrete components, or may be formed as a “distributed” filter along the length of the optical fiber. The cut-off frequency for the high pass optical filter is selected to be immediately below the frequency of the input channel to be transmitted. When used in an arrangement with multiple input channels, the cut-off frequency is controlled to be immediately below the lowest input channel frequency.

Abstract: A synchronous rectifier for use with a clamped-mode power converter uses in one embodiment a hybrid rectifier with a MOSFET rectifying device active in one first cyclic interval or the conduction/nonconduction sequence of the power switch and a second rectifying device embodied in one illustrative embodiment as a low voltage bipolar diode rectifying device active during an alternative interval to the first conduction/nonconduction interval. The gate drive to the MOSFET device is continuous at a constant level for substantially all of the second interval which enhances efficiency of the rectifier. The bipolar rectifier device may also be embodied as a MOSFET deice. The subject rectifier may be used in both forward and flyback power converters.