Abstract: A method is disclosed for determining the admissibility of an offered session of traffic of a specified class to a server in a packetized communication network. Each class c has a peak traffic rate r(c). The server has a total processing rate C. Admitted packets are scheduled according to an EDF scheduling discipline. The method for determining admissibility comprises defining an operating point for the server. The operating point represents the number of sessions Nc of each respective class currently offered or currently being served. The method further comprises determining whether the defined operating point falls within a set of operating points that together define an admissible region. The admissible region consists of operating points for which the probability of violating a delay bound for any packet is below a threshold. The determination of the admissible region involves principles of statistical multiplexing.

Abstract: A new approach is described for scheduling uplink or downlink transmissions in a network having remote terminals communicating with a central hub. The scheduler keeps track of a token count. The token count for a given remote terminal is incremented by a target amount in each pertinent timeslot, but is also decremented each time that the remote terminal is served. The amount of the decrement for one timeslot is the amount of data served, i.e., transmitted to or from the remote terminal, in that timeslot. In exemplary embodiments of the invention, the target amount by which T is incremented depends on the current value of T. Whenever the token count is non-negative (i.e., whenever it has a positive or zero value), the target amount is a desired floor, or lower limit, on an average amount of data delivered to or from the given remote terminal in one timeslot. Whenever the token count is negative, the target amount is a desired ceiling, or upper limit, on the same average amount of data delivered.

Abstract: We disclose a method of dynamic channel assignment for wireless transmission systems that employ time or frequency multiplexing, or both time and frequency multiplexing. The invention is specifically addressed to the problem of avoiding interference in the channels of such systems. In a broad aspect, the invention involves partitioning base stations of a network into non-interfering sets. Channels are allocated to the non-interfering sets according to need. Stages of channel reallocation take place periodically. The reallocation takes place through coordinated activity by the base stations. That is, the channel reallocation is carried out in response to information that is exchanged between base stations, or it is centrally directed by the network in response to information passed to the network by the base stations.

Abstract: A method is disclosed, for designing an access network that is to carry communication traffic between end nodes and a core network. Information is provided that describes end node locations, the level of demand associated with each end node, available trunk types and their related capacities, and a cost structure. The cost structure includes a fixed overhead cost for each trunk type, and a service charge per unit distance for each trunk type. The provided information is incorporated in a linear program to find an optimal-cost access network. The linear program is solved to obtain a provisional solution that defines the composition and usage of each link of the optimal-cost access network. For each such link, the composition is defined by a fractional level of investment (incurring a like fraction of the corresponding overhead charge) in each pertinent trunk type.

Abstract: A fixture for releasable retaining at least one lenticular article in a fixed orientation while the article(s) is/are being subjected to one or more applications of a thin film coating process comprises a perforated metallic sheet having at least one aperture therein adapted to receive the article(s). The thickness of the metal fixture bears a ratio to the size of the articles being retained that is within a particular range. A method for applying thin film optical coatings to lenticular articles utilizing such a fixture is also disclosed.

Abstract: A ceramic hot-gas candle filter having a porous support of filament-wound oxide ceramic yarn at least partially surrounded by a porous refractory oxide ceramic matrix, and a membrane layer on at least one surface thereof. The membrane layer may be on the outer surface, the inner surface, or both the outer and inner surface of the porous support. The membrane layer may be formed of an ordered arrangement of circularly wound, continuous filament oxide ceramic yarn, a ceramic filler material which is less permeable than the filament-wound support structure, or some combination of continuous filament and filler material. A particularly effective membrane layer features circularly wound filament with gaps intentionally placed between adjacent windings, and a filler material of ceramic particulates uniformly distributed throughout the gap region. The filter can withstand thermal cycling during backpulse cleaning and is resistant to chemical degradation at high temperatures.

Abstract: A packet routing technique which is stable for all networks in the presence of input blocking and output blocking. The packets injected within a network are examined and based on a historical perspective of those packets a determination is made on how to route individual packets throughout the network in a stable manner. In particular, in order to achieve complete network stability, individual switches within the network need to choose matchings, i.e., input to output port connections, that reflect the demand on each port-pair within the switches. Thus, if all packets are guaranteed to be in the network for at most a maximum number of time blocks, then a particular switch will have seen all the packets injected in the network at least that maximum number of blocks ago.

Abstract: Providing a compositional image of an object in real time is accomplished by illuminating the object with a waveform comprising pulses of electromagnetic radiation in the terahertz frequency range and measuring the relative time delays of pulses reflected by the object to determine the positions of dielectric interfaces in the object. According to a further embodiment, the waveform includes one or more pulses of terahertz radiation, each pulse having a duration in the range of approximately 10 to 10,000 femtoseconds.

Abstract: A fixture for releasably retaining at least one lenticular article in a fixed orientation while the article(s) is/are being subjected to one or more applications of a thin film coating process comprises a perforated metallic sheet having at least one aperture therein adapted to receive the article(s). The thickness of the metal fixture bears a ratio to the size of the articles being retained that is within a particular range. A method for applying thin film optical coatings to lenticular articles utilizing such a fixture is also disclosed.

Abstract: A time-domain signal processing system for displaying, classifying, and recognizing temporal and spectral features in terahertz waveforms returned form materials. Specifically, novel techniques are described for classifying and analyzing the free induction decay exhibited by gases excited by far-infrared (terahertz) pulses. Illustratively, a simple geometric picture may be used for the classification of the waveforms measured for unknown gas species and gas mixtures.

Abstract: A ceramic hot-gas candle filter having a porous support of filament-wound oxide ceramic yarn at least partially surrounded by a porous refractory oxide ceramic matrix, and a membrane layer on at least one surface thereof. The membrane layer may be on the outer surface, the inner surface, or both the outer and inner surface of the porous support. The membrane layer may be formed of an ordered arrangement of circularly wound, continuous filament oxide ceramic yarn, a ceramic filler material which is less permeable than the filament-wound support structure, or some combination of continuous filament and filler material. A particularly effective membrane layer features circularly wound filament with gaps intentionally placed between adjacent windings, and a filler material of ceramic particulates uniformly distributed throughout the gap region. The filter can withstand thermal cycling during backpulse cleaning and is resistant to chemical degradation at high temperatures.