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: An integrated piezo-resistive sensor for determining mirror position in an optical switch. One or more piezo-resistive layers may be formed in silicon springs supporting a movable mirror in the switch. Change in resistivity of those layers due to spring deformation during mirror motion is measured and related to the mirror deflection angle. Information about the angle may be used to provide feedback to the motion actuator, which then may be operated to orient the mirror more accurately. A sensor's sensitivity may be increased by appropriately orienting the springs with respect to the crystallographic axes of the silicon.

Abstract: A novel communication system allows telephone customers to send and retrieve e-mail using only conventional telephone units. The system includes an “E-mail Device” (EMD), which is a special host computer for enabling customers to remotely create, send, retrieve and store e-mail messages. The EMD resides in the central office as part of a PSTN, or with an Internet Service Provider (ISP). Subscribers to the e-mail service can give calling parties the option of leaving e-mail messages when the subscribers' telephone lines are busy. Customers can also create and send e-mail messages by either dialing an access code to connect directly to the EMD, or dialing an ISP with a resident EMD. Once connected to the EMD, the customer is guided through menus to send either pre-stored or custom e-mail messages to a chosen customer, telephone number, or e-mail address. The message information and details are entered via the touch-tone pad, or by voice, followed with voice-to-text conversion.

Abstract: An adjustable compound optical microlens apparatus comprises first and second microlenses that are separated from one another along their optical axes. At least one of the microlenses is movable relative to the other. In a preferred embodiment, one microlens is stationary, the other movable. A MEMS controller electrically controls the position of the movable microlens relative to the stationary microlens, or the positions of at least two movable microlenses relative to one another. In accordance with one embodiment of our invention, an array of such microlens apparatuses is also contemplated, especially for applications such optical switches and routers. In accordance with another embodiment of our invention, the apparatus functions as an optical filter or dispersion compensator. Also described is method of compensating for variations in an optical parameter (e.g., effective focal length) of such an apparatus in an array.

Abstract: Data storage techniques particularly well-suited for use in archival data storage are disclosed. In one aspect of the invention, a data block is processed to generate an address as a function of the contents of the data block, and the data block is then stored in the system in a memory location identified by the address. The processing operation is configured to provide write-once archival storage of the data block, in that the contents of the data block are not modifiable without also altering the address of the data block determinable in the processing operation. In an illustrative embodiment, the processing of the data block involves determining a substantially unique identifier of the data block by applying a collision-resistant hash function to the contents of the data block, and the address is subsequently determined from the substantially unique identifier by utilizing the identifier to perform a lookup of the address in an index.

Abstract: A method and apparatus for controlling the pump powers of a broadband DWDM optical system using Raman amplification which determines pump settings that advantageously minimize the peak-to-peak ripple of the channel powers with respect to a given per-channel target. The illustrative method and apparatus first formulates a linear programming optimization problem, and then solves the formulated linear program in order to derive a new set of pump powers to be applied to the Raman amplification pumps. Illustratively, the linear program may be solved with use of any conventional linear programming solution technique, such as, for example, the simplex method.

Abstract: A GPRS interworking and interoperability function (IIF) is interposed between a serving GSM/GPRS wireless system and a second wireless system of a different technology family to allow a mobile station homed to the second wireless system to operate in the GSM/GPRS system. The IIF executes or emulates the behavior of a GPRS HLR when communicating with the GSM/GPRS system, and executes or emulates the behavior of an MSC/VLR of the home system technology family when communicating with the home system. When a mobile station registers in the serving system, the MSC/VLR portion of the IIF transmits a registration notification message to the home system HLR specifying the address of an associated SGSN as though it were an MSC.

Abstract: A method for fabricating a bipolar transistor includes forming a vertical sequence of semiconductor layers, forming an implant mask on the last formed semiconductor layer, and implanting dopant ions into a portion of one or more of the semiconductor layers. The sequence of semiconductor layers includes a collector layer, a base layer that is in contact with the collector layer, and an emitter layer that is in contact with the base layer. The implanting uses a process in which the implant mask stops dopant ions from penetrating into a portion of the sequence of layers.

Abstract: Cooling means are provided for directing cooling air over a desired portion of an electronic components card. A deflector attachable to the electronic components card for directing cooling air over the card is provided. The deflector is adapted to be moved with respect to the card to direct cooling air over different portions of the card. The deflector includes a scoop extending along the plane of the card and beyond the edge of the card when the deflector is attached to the card for redirecting cooling air over the card. The deflector can include a pair of walls having spaced apart interior surfaces forming a channel for receiving the card for attaching the deflector to the card. A method for cooling an electronic components card includes providing a deflector having a scoop for redirecting cooling air and attaching the deflector to the card so that the scoop directs cooling air over the card to cool the electronic components.

Abstract: An arbitrary gap between the two chips of a MEMS device arranged in a flip-chip arrangement is achieved by etching into a first substrate to form mesas which act as spacers between which, or even on which, any required circuit elements are formed. Points of a layer at a first surface of the second substrate within which MEMS structures are made are bonded to the mesas of the first substrate. The second substrate is then removed, leaving the structures bonded to the mesas. The mesas may be formed by placing a hard mask, such as silicon oxide, which defines the desired pattern of mesas on the first substrate, and then etching the unmasked portion of the substrate using a mixture of potassium hydroxide (KOH) with isopropanol (IPA) or, tetramethyl ammonium hydroxide (TMAH) mixed with a surfactant, e.g., nonylphenol ethoxy ether or other equivalent compounds.

Abstract: A channel detection system includes an interferometer coupled to a spectrum analyzer to differentiate additive spontaneous emission (ASE) noise from optical channels in a dense wave-division multiplex (DWDM) signal. It is assumed that channels, if present, are centered at frequencies corresponding to a standardized channel grid. The relative delay of the interferometer is chosen to be greater than the coherence time of the ASE noise but less than the coherence time of the channels with the interferometer's free spectral range set to an integer divisor of the channel-to-channel frequency spacing of the grid such that active channels experience a high degree of interference. The phase delay of the interferometer is then adjusted to maximize the interference at each grid-aligned frequency. The spectrum-analyzed outputs are compared (e.g., subtracted from one another and then thresholded) to determine the channels present in the DWDM signal.

Abstract: The system for frame selector migration in 3G cellular networks enables the frame selector function to be migrated to the presently active Radio Network Controller without disruption of the call. This migration strategy functions to reduce the number of handoff legs required to serve an existing call connection, therefore more efficiently utilizing the network resources. The system for frame selector migration in 3G cellular networks also optionally uses a hierarchy of frame selectors, which makes use of multiple levels of frame selectors in the cellular network to simplify the migration of the frame selector function.

Abstract: Configurations for optical waveguide crossings are described. In one exemplary implementation, an optical chip includes waveguides integrated on the optical chip. The waveguides have varied widths dependent upon how many waveguides each of the waveguides cross with respect to each other. In another exemplary implementation, voids are inserted between waveguides in the vicinity of waveguide crossings of an optical device. The voids are configured to reduce optical losses in waveguides that have more waveguide crossing while simultaneously increasing optical losses in waveguides that have fewer waveguide crossings. Accordingly, the overall optical losses between the waveguides are generally equalized with respect to each other.

Abstract: Methods and apparatus are provided for designing IP networks with substantially improved performance as compared to existing IP networks such as, for example, those networks designed under best-effort criteria. Particularly, the invention includes methods and apparatus for: computing worst-case and optimistic link capacity requirements; optimizing network topology; and determining router placement within a network.

Abstract: Methods and apparatus for performing near lossless-concatenated N-level constrained quantization Hadamard transform decoding are provided. Accordingly, the present invention provides a transform-based coding technique, where the coding loss introduced during repeated encoding and decoding is reduced to a substantially insignificant level. This is accomplished by employing a constrained quantization and inverse quantization operation in each level of encoding/decoding in the decoder. In this manner, the concatenation error between each level of a decoder is reduced to a substantially minimum level and the quantization error introduced during quantization operations, i.e., originally at the encoder and in each level of the decoder, is substantially reduced. Thus, the decoded bit stream that is output at the N-th level of the decoder is substantially the same as the original bit stream provided to the input of the encoder.

Abstract: Overload conditions affecting a processor of a network switch or the like are substantially eliminated, and the processing of traffic is gradually allowed to increase, by inserting, and then monitoring one or more probes which are placed into a queue of the processor. During a given measurement interval, if the number of probes exceeds a threshold then an overload condition exists. This condition is subsequently reduced using “multiplicative decrease” techniques. Conversely, if the threshold is not exceeded and there is little or no chance an overload condition can quickly reappear, traffic is allowed to once again be processed gradually using “additive increase” techniques.

Abstract: A field programmable gate array assembly (100, 200, 300) offers the unique functionality typically reserved for custom ICs and application specific integrated circuits (ASICs) with the flexibility of a programmable gate array. This is accomplished by modifying a package for a programmable IC (102), such as a programmable gate array, to electrically and mechanically couple to another IC (104). The preferred electrical and mechanical coupling occurs by stacking the IC on the programmable IC.

Abstract: The existing paging infrastructure is used to send commands to operate remotely-located electronic or mechanical devices. A paging message containing one or more pre-set commands, trigger signals, or command strings is received by a paging receiver into an optional signal buffer which provides the received message to a message compare function. The message compare matches each component of the message to a set of one or more allowed commands and sends at least one signal or command that causes the action specified by the received message contents to take place at the target device. The command may be a signal for triggering an electronic or mechanical action, or may be a command that causes an operation to be performed in a software-controlled component of the target device. An alternate embodiment allows responses generated by the system and/or the target device to be forwarded back to the initiator via a two-way paging transceiver.

Abstract: In accordance with the invention, an MZI-based reconfigurable multi-channel filter is provided with enhanced channel bandwidth by adding an all-pass filter to one or both of the MZI arms. The result is a square-shaped amplitude response closely approximating the ideal.

Abstract: A method and apparatus for controlling telecommunications call processing is disclosed. In a switching system, a Master Controller is provided for maintaining the database of the system, and for receiving call processing control messages. The Master Controller receives these messages via a core switching fabric network of the switching system. The Master Controller selects one of a plurality of feature processors, the feature processors being of several types for processing different features, to process the received call processing message. The Master Controller, if necessary, transmits not only the call processing message, but also state information about the call to the selected feature processor. The feature processor processes the message, and returns call state update data to the Master Controller. The feature processor also transmits messages for controlling other units in order to implement the desired response to the received call processing message.