Multidimensional Declustering Schemes Using Golden Ratio and Kronecker Sequences

  • Bhatia R.
  • C-M. Chen
  • R.K. Sinha

We propose a new data declustering scheme, GRS, for range queries on uniform data. Our scheme is based on Golden Ratio Sequences for two dimensions and Kronecker Sequences for higher dinensions. Using exhaustive simulation we show that, in two dimensions, the worst case (additive) deviation of GRS from the optimal ...

Uplink Scheduling in CDMA Packet-Data Systems

  • Kumaran K.
  • Qian L.

Uplink scheduling in wireless systems is gaining importance due to arising uplink intensive data services (ftp, image uploads etc.), which could be hampered by the currently in-built asymmetry in favor of the downlink. In this work, we propose and study algorithms for efficient uplink packet-data scheduling in a CDMA cell. ...

Instability of the Proportional Fair Scheduling Algorithm for HDR

  • Andrews D.

In this paper we study the Proportional Fair Scheduler that has been proposed for scheduling in the High Data Rate (HDR) wireless data system [4,6]. We consider a single basestation transmitting to a set of mobile users. In each time slot the scheduler has to decide on a mobile to ...

Forward and Reverse Link Capacity for 1xEV-DO: Third Generation Wireless High-Speed Data Systems

  • Bi Q.
  • Brown R.
  • Cui D.
  • Gandhi A.
  • Huang C.

This paper presents the performance results of a 1xEV-DO system. With different fading channels, data rate control lengths and overhead channel power levels, the system performance will vary. While optimizing the forward-link throughput becomes critical for asymmetric traffic demand, it is important to ensure that the reverse-link throughput is sufficient ...

Understanding TCP Fairness Over Wireless LAN

  • D. Raz
  • Ramjee R.
  • S. Pilosof
  • Sinha P.
  • Y. Shavitt

As local area wireless networks based on the IEEE 802.11 standard see increasing public deployment, it is important to ensure that access to the network by different users remains fair. While fairness issues in 802.11 networks have been studied before, this paper is the first to focus on TCP fairness ...

Throughput and Energy Efficiency in Topology-Controlled Multi-Hop Wireless Sensor Networks

  • Li L.
  • Sinha P.

In this paper, we examine the effect of topology control on network capacity and energy efficiency. As compared to fixed transmission power, our analysis shows that the capacity improvements depend on the reliability of link layer transmissions and traffic patterns. Specifically, if link layer does not retransmit, network capacity decreases ...

Tutorial: Prosody and Prosodic Models

  • Kochanski G.
  • Shih C.

The tutorial will summarize the state of the art of prosody research with an emphasis on intonation (f0). We will present it in a data- and knowledge-driven fashion, starting with speech data and physiology, and building towards quantitative models. We will cover a wide range of intonation phenomena, discussing the ...

Voronoi Diagrams and Delaunay Triangulations

  • Fortune S.

The Voronoi diagram of a set of sites partitions space into regions, one per site; the region for a site s consists of all points closer to s than to any other site. The dual of the Voronoi diagram, the Delaunay triangulation, is the unique triangulation such that the circumsphere ...

Experimental Demonstration of Adaptive Distributed Transmission Scheme for Indoor Wireless Networks

  • Chow C.

Adaptive Distributed Transmission (ADT) is a novel scheme for transmission of data in a wireless network. ADT coordinates the transmissions of base stations in order to increase the overall throughput of the network. This gain is achieved through exploiting the space resource, by cooperatively compensating for the phase and amplitude ...

Minimal group refractive index dispersion and gain evolution in ultra-broad-band quantum cascade lasers

  • Capasso F.
  • Cho A.
  • Colombelli R.
  • Gmachl C.
  • Sivco D.
  • Soibel A.

Quantum cascade (QC) lasers [1] are based on optical intersubband transitions between quantized states in the conduction band of multiple coupled quantum wells. Four distinct characteristics contribute to the uniqueness of the QC-laser. First, the peak wavelength of the active region can be chosen freely over a very wide range ...

Resonant Second-Order Nonlinear Optical Processes in Quantum Cascade Lasers

  • A. Belyanin
  • Capasso F.
  • Cho A.
  • Colombelli R.
  • Gmachl C.
  • N. Owschimikow
  • Sivco D.
  • V. Kocharovsky

We demonstrate an efficient intracavity nonlinear interaction of laser modes in a specially adapted quantum cascade (QC) laser. A two-wavelength QC laser structure operating at 7.1 and 9.5 mum wavelength included cascaded resonant optical intersubband transitions in an intracavity configuration leading to resonantly enhanced sum-frequency and second-harmonic generation at 4.1 ...

Tunable Microfluidic Optical Fiber Devices Based On Electrowetting Pumps And Plastic Microchannels

  • Baldwin K.
  • Cattaneo F.
  • Hsieh J.
  • Mach P.
  • Rogers J.
  • T. Krupenkine
  • Yang S.

This paper introduces a class of tunable microfluidic fiber devices that uses molded plastic microchannels and electrowetting pumps. It demonstrates the application of this type of system to dynamically adjustable narrow band and wide band all-fiber filters. Compact size, low cost fabrication procedures, low power (<1 mW) consumption, non-mechanical operation ...

Scheduling Over a Time-Varying User-Dependent Channel with Applications to High Speed Wireless Data

  • Andrews D.
  • Zhang Y.

In a wireless network, a basestation transmits data to mobiles at time-varying, mobile-dependent rates due to the ever changing nature of the communication channels. In this paper we consider a wireless system in which the channel conditions and data arrival processes are governed by an adversary. We first consider a ...

Selective Suppression of Idler Spectral Broadening in Two-Pump Parametric Architectures

  • C. Headley
  • C.G. Jorgensen
  • Centanni J.
  • Chraplyvy A.
  • Jopson R.
  • K. Brar
  • Mckinstrie C.
  • Radic S.

We describe methods for selective suppression of idler spectral broadening in two-pump parametric fiber amplifiers. Combinations of multiple amplification bands and dissimilar pump modulation techniques are used to generate narrow idlers at preselected wavelengths. In-phase modulation of parametric pumps is demonstrated as a feasible technique that can eliminate the need ...

Scheduling a Multi-Class Queue with Many Exponential Servers: Asymptotic Optimality in Heavy-Traffic

  • A. Mandelbaum
  • R. Atar
  • Reiman M.

We consider the problem of scheduling a queueing system in which many statistically identical servers cater to several classes of impatient customers. Service times and impatience clocks are exponential while arrival processes are renewal. Our cost is an expected cumulative discounted function, linear or non-linear, of appropriately normalized performance measures.

Wavelength Assignment for Partially Transparent Networks with Reach Constraints

  • Kumaran K.
  • Nuzman C.
  • Widjaja I.

In this work, we propose and study a class of wavelength assignment (WA) algorithms, based on shortest-path computation in auxiliary graphs, which are designed to meet these goals. The graph construction ensures that the wavelength assignment meets reach constraints, tunability constraints, and other limitations imposed by the network. By appropriate ...

Yang-Lee Singularity of Two Dimensional Ising and Potts Models

  • Mccabe J.
  • T. Wydro

This presentation reviews numerical studies of Yang-Lee singularities in 2D spin models. The studies focus on finite-size scaling behavior of quantum spin chains and how that behavior can be used to obtain information on Yang-Lee singularities of associated 2D spin models. The studies obtain values for Fisher's sigma exponent and ...

Resource-Optimized Delivery of Web Images to Small-Screen Devices

  • Lopresti D.
  • Wu Y.

In this paper, a framework for adaptive delivery of web images to small-screen devices has been presented. The proposed system provides content-level scalability by unifying image analysis, compression, optimized content adaptation, and user interaction. We have proposed a way to establish the rate-distortion information for each representation of the objects. ...

Wide-Sense Nonblocking WDM Cross-Connects

  • A. Rasala
  • Haxell P.
  • Wilfong G.
  • Winkler P.

We consider the problem of minimizing the number of wavelength interchangers in the design of wide-sense nonblocking cross-connects for wavelength division multiplexed (WDM) optical networks. The problem is modeled as a graph theoretic problem that we call dynamic edge coloring. In dynamic edge coloring the nodes of a graph are ...

Hierarchical Stochastic Feature Matching with Application to Hands-Free Speech Recognition

  • Jiang H.
  • Lee C.
  • Soong F.

In this paper, we improve hands-free speech recognition performance with a new "blind" feature compensation technique, using only hands-free test utterances and pre-trained HMM models (mismatched or matched) for compensation. Due to the complex nature of distortions in hands-free speech signals and limited available data for compensation, we propose to ...