Very Concurrent Mark-&-Sweep Garbage Collection without Fine-Grain Synchronization

  • Huelsbergen L.
  • Winterbottom P.

We describe a new incremental algorithm for the concurrent reclamation of a program's allocated, yet unreachable, data. Our algorithm is a variant of mark-&-sweep collection that--unlike prior designs-- runs mutator, marker, and sweeper threads concurrently without explicit fine-grain synchronizaton on shared-memory multiprocessors. A global, but infrequent, synchronization coordinates the per-object ...

Writer Independent On-Line Handwriting Recognition Using an HMM Approach

  • Brown M.
  • Hu J.
  • Lim S.

In this paper, we describe a Hidden Markov Model (HMM) based writer independent handwriting recognition system. A combination of signal normalization preprocessing and the use of invariant features makes the system robust with respect to variability among different writers as well as different writing environments and ink collection mechanisms. A ...

Efficient Chip Design for Pulse Shaping

  • Balakrishnan J.
  • Rupp M.

This note presents a new idea for implementing the pulse shaping filter in the transmitter part of a modem. It will be shown that for QPSK modulation and other higher order modulations like 16/32/64 QAM no multiplication is required at all while the number of multiplications for 8PSK (and 16/32PSK) ...

Power Amplifier MMIC for Microwave Digital Radio

  • Chen Y.
  • Giguet J.
  • Roux P.
  • Tsai H.

Microwave digital link has received much attention in recent years because it offers broad bandwidth which can fulfill the ever increase demand for high-speed voice and data networks. In this paper, we will discuss the design of a broadband (10GHz to 16GHz) power amplifier MMIC, which will replace the current ...

Interval Packing: The Vacant Interval Distribution

  • Coffman E.
  • Flatto L.
  • Jelenkovic P.

Starting at time 0, unit-length intervals arrive and are placed on the positive real line by a unit-intensity Poisson process in two dimensions; the left endpoints of intervals appear at the rate of 1 per unit time per unit distance. An arrival is accepted if, and only if, for some ...

Degradation of DC Characteristics of InGaAs/InP Single Heterojunction Bipolar Transistors under Electron Irradiation

  • Bandyopadhyay A.
  • Chandrasekhar S.
  • Dentai A.
  • Goodnick S.
  • Subramanian S.

The effects of high energy (~1 MeV) electron irradiation on the DC characteristics of InGaAs/InP single heterojunction bipolar transistors (SHBTs) are investigated. The device characteristics do not show any significant change for electron doses <10 sup (15)/cm sup 2. For higher doses, devices show a decrease in collector current, a ...

Resistivity of Lightly Doped Ferromagnetic Semiconductors

  • Littlewood P.
  • Majumdar P.

In metallic magnets with a low carrier density, scattering from magnetic fluctuations above and near the transition temperature T sub c provides a large contribution to the electrical resistance. Because the fluctuations can be suppressed by a magnetic field, a large negative magnetoresistance ensues. In a simple model, we find ...

Minimizing End-to-End Delay in High-Speed Networks with a Simple Coordinated Schedule

  • Andrews M.
  • Zhang L.

We study the problem of providing end-to-end delay guarantees in connection-oriented networks. In this environment, multiple-hop sessions coexist and interfere with one another. Parekh and Gallager showed that the Weighted Fair Queueing (WFQ) scheduling discipline provides a worst-case delay guarantee comparable to 1 over pi x K sub i for ...

Hall Effect in the Perovskite Manganites

  • Majumdar P.
  • Sengupta A.
  • Simon S.

We compute the zero temperature phase diagram and the Hall response of the doped perovskite manganites within the model of double exchange and Jahn-Teller coupling, employing the d -> inf approximation proposed by Millis, et al. We find that in this scenario a "hole-like" R sub H for the hole ...

Organic Materials Challenges for 193 NM Imaging

  • Houlihan F.
  • Nalamasu O.
  • Reichmanis E.

Photolithography using 193 nm radiation is the leading candidate for the manufacture of 0.18-0.13 micron design rule devices. The optical absorption of materials such as novolacs, and functionalized poly(hydroxystyrenes) and styrene-acrylate copolymers, which are the matrix materials of choice for G line, I line, and 248 nm lithography, is significantly ...

Micromachined Optical-Interference Microphone

  • Greywall D.

A design is proposed for a micromachined microphone which utilizes optical interference to sense the sound-induced motion of a thin diaphragm. The light source and detector can be included as components of the device or can be at a remote location and joined to the microphone with an optical fiber. ...

Phase Stability Solubility and Hydrothermal Crystal Growth of PbTiO sub 3

  • Gelabert M.
  • Laudise R.
  • Riman R.

PbTiO sub 3 phase stability and crystal growth were investigated under hydrothermal conditions near 500C. Solubility of PbTiO sub 3 was measured from 350-600C; dependence on pressure and mineralizer was also determined. The PbO-TiO sub 2-H sub 2 O phase diagram in 3.2km KF shows a narrow region of PbO ...

A 15mW, 155Mb/s CMOS Burst-Mode Laser Driver with Automatic Power Control

  • Fischer W.
  • Gabara T.
  • Ota Y.
  • Sackinger E.

The design of a low-power, burst-mode laser driver for use in passive optical networks (PON) is described. The laser driver can operate at 50 Mb/s or 155 Mb/s. It features automatic control of the optimal output power (APC) as well as end-of-life detection of the laser diode. The driver is ...

Design and Performance of Underlay-Overlay Cellular Networks

  • Kumaran K.
  • Whiting P.

We study the design and performance of Underlay-Overlay (U-O) wireless networks, in which the available spectrum is partitioned into two groups - an overlay group with a conservative reuse factor, and an underlay group with a more frequent reuse. A key performance factor is the absorption, i.e., the proportion of ...

RF Flip-Module BGA Package

  • Degani Y.
  • Dudderar T.
  • Frye R.
  • Gregus J.
  • Guinn K.
  • Low Y.

We recently described a flip-chip package with integrated thin-film inductors and capacitors in a VCO tank circuit of a single-chip GSM transceiver IC. By embedding the passive components in a Si-on-Si substrate, we eliminated spurious resonances that were caused by the parasitics of the original 64-TQFP IC package. However, compared ...

Fast, Fair and Frugal Bandwidth Allocation in ATM Networks

  • Bartal Y.
  • Farach-Colton M.
  • Yooseph S.
  • Zhang L.

ATM networks are used to carry a variety of types of traffic. For some types of traffic, in particular Available Bit Rate (ABR) traffic, the bandwidth of a network is typically insufficient to satisfy the requests of all the sessions, and so some fair allocation scheme must be devised. The ...

Photopolymer-Filled Nanoporous Glass as a Dimensionally Stable Holographic Storage Medium

  • Dhar L.
  • Patel S.
  • Schilling M.
  • Schnoes M.
  • Wiltzius P.

Plane-wave holograms were angle-multiplexed in a photopolymer-filled nanoporous glass system. The angular selectivity curves of the multiplexed holograms were in agreement with predictions from Kogelnik's coupled wave theory of volume phase holograms. The recorded holograms also exhibited nearly negligible Bragg detuning. This system exhibits the high dimensional stability that is ...

Binomial Moments of the Distance Distribution: Bounds and Applications

  • Ashikhmin A.
  • Barg A.

We study a combinatorial invariant of codes which counts the number of ordered pairs of codewords in all subcodes of restricted support in a code. This invariant can be expressed as a linear form of the components of the distribution of the code with binomial numbers as coefficients. For this ...

Reduced-Order Modeling of Time-Varying Systems

  • Roychowdhury J.

We present a theory for reduced-order modeling of linear time-varying systems, together with efficient numerical methods for application to large systems. The technique, called TVP (Time-Varying Pade), is applicable to deterministic as well as noise analysis of many types of communication subsystems, such as mixers and switched-capacitor filters, for which ...

Trifocal Tensors for Weak Perspective and Paraperspective Projections

  • Bruckstein A.
  • Holt R.
  • Huang T.
  • Netravali A.

Trilinear relationships among the image point coordinates obtained by perspective projection of several feature points over three views have been investigated, and it has been shown that seven point correspondences are sufficient to determine the coefficients involved. We show that analogous trilinear relationships exist for the weak perspective and paraperspective ...