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 TitleDate AddedCompany
whitepaper On Orthogonal Reduction to Hessenberg Form With Small Bandwidth2008-06-12 Academy of Sciences of the Czech Republic
  Numerous algorithms in numerical linear algebra are based on the reduction of a given matrix A to a more convenient form. One of the most useful types of such reduction is the orthogonal reduction to (upper) Hessenberg form. This reduction can be computed by the Arnoldi algorithm. When A is Hermitian, the resulting upper Hessenberg matrix is tridiagonal, which is a significant computational advantage. This paper studies necessary and sufficient conditions on A so that the orthogonal Hessenberg reduction yields a Hessenberg matrix with small bandwidth. This includes the orthogonal reduction to tridiagonal form as a special case. Orthogonality here is meant with respect to some given but unspecified inner product.

Tags: Software Engineering		   
whitepaper A Two-Stage Plug-in Bandwidth Selection and Its Implementation for Covariance Estimation2008-06-01 Concordia University
  The two most popular bandwidth choice rules for kernel HAC estimation have been proposed by Andrews (1991) and Newey and West (1994). This paper suggests an alternative approach that estimates an unknown quantity in the optimal bandwidth for the HAC estimator (called normalized curvature) using a general class of kernels, and derives the optimal bandwidth that minimizes the asymptotic mean squared error of the estimator of normalized curvature. It is shown that the optimal bandwidth for the kernel-smoothed normalized curvature estimator should diverge at a slower rate than that of the HAC estimator using the same kernel.   
whitepaper Bandwidth Consumption Control and Service Differentiation for Video Streaming2008-05-19 Electronics and Telecommunications Research Institute
  Multimedia streaming is resource demanding. It may starve other applications such as file transfer sharing the network, for example, in a smart home. To address the problem, a fuzzy logic control to bound the bandwidth consumption of multimedia streams is applied. This paper also differentiates the video quality for streams with different levels of importance. The transmission rate control and service differentiation schemes are implemented and evaluated in the department network where a number of different applications may coexist at the same time. Performance evaluation results show that the video streaming system can support the specified bit rate bound and differentiate the service to efficiently utilize the limited bandwidth.

Tags: Streaming Media, Multimedia		   
whitepaper A Novel Coding Technique to Minimise the Transmission Bandwidth and Bit Error Rate in DPSK2008-05-01 JNT UNIVERSITY
  This paper proposes a novel coding technique that aims to reduce the Transmission Bandwidth (BT) and Bit Error Rate (BER) vis-a-vis Conventional Differential Phase Shift Keying (CDPSK) in digital band pass transmission. In CDPSK two successive bits are used for encoding. The proposed method encodes information with respect to the consecutive two bits b(t-Tb) and b(t-2Tb). The encoded data is keyed on to the phase. The received signal is demodulated by using the present phase ö(t) and the two phases ö(t-Tb) and ö(t-2Tb). Comparative analysis between the two techniques reveals the advantages of the proposed technique.

Tags: Programming Languages		   
whitepaper Convergence Analysis of Iteratively Detected Time Hopping and DS-CDMA Ultrawide Bandwidth Systems by EXIT Charts2008-04-15 Institute of Electrical and Electronics Engineers
  This paper presents a novel analysis on the decoding convergence of Time Hopping (TH) and Direct Sequence (DS) Code-Division Multiple-Access (CDMA) Ultrawide Bandwidth (UWB) systems when communicating over multipath Nakagami channels. The analysis is based on the Extrinsic Information Transfer (EXIT) chart where the UWB systems are serially concatenated pulse-position modulated TH and code-synchronous DS-CDMA. It is shown from an EXIT chart analysis that the multipath diversity can yield a larger area under the EXIT curve of the inner detector. This area is related to the achievable rate of the system and it can be exploited with the aid of iterative detection. Simulation results of the iteratively detected TH and DS-CDMA UWB schemes verify the EXIT chart analysis.

Tags: Mobile - Wireless Communications, TDMA - CDMA		   
whitepaper A Full Bandwidth Calibrator for a Sound Pressure and Particle Velocity Sensor2008-03-10 Hogeschool van Arnhem en Nijmegen
  In literature it is shown that it is possible to calibrate a sound pressure and a particle velocity sensor in the free field at higher frequencies. This is done by calculating the acoustic impedance at a certain distance of a spherical loudspeaker. If the sound pressure is measured with a reference microphone the particle velocity can be calculated. At lower frequencies this setup does not work. The pressure microphone is calibrated by comparing its response with the reference microphone. In this paper the method is extended for lower frequencies by placing the reference microphone in the loudspeaker.   
whitepaper Microsoft Dynamics CRM 4.0: Performance and Scalability - Bandwidth Utilization Improvements2008-03-01 Microsoft
  Microsoft Dynamics CRM business software is designed to help enterprise organizations achieve a 360-degree view of their customers across marketing, sales, and service. Engineered to deliver performance that meets the needs of the largest global deployments, Microsoft Dynamics CRM has been tested for user scalability, data scalability, and network performance. This white paper focuses on network scalability improvements.

Microsoft has made significant enhancements to the architecture of Microsoft Dynamics CRM 4.0 to improve network performance. Test results demonstrate network bandwidth utilization improvements of up to 94%. Improvements were evaluated in the number of round trips, bytes sent, and bytes received. Because the bandwidth utilization associated with a page can change after the first time the page is loaded, both initial (cold) and subsequent (warm) page loads were tested.

Tags: Scalability, CRM Software, Network Design, High Performance Computing		   
whitepaper Achieving High Throughput in Low Multiplexed, High Bandwidth, High Delay Environments2008-01-01 Columbia University
  This paper explores combining ECN bits and loss feedback to achieve a high throughput connection in a high bandwidth, low multiplexed environment. In the scheme, a TCP source reacts differently on receiving an ECN than it does on inferring a packet loss in terms of congestion window update. Coupled with an AQM scheme such as RED, TCP sources achieve high utilization at a bottleneck router, but at the cost of fairness. The paper introduces a lightweight AQM mechanism that ensures fairness while still providing high utilization to the sources. The proposal is complementary to the HSTCP modification suggested by Floyd et al.

Tags: TCP - IP		   
whitepaper Bandwidth Estimation: Metrics, Measurement Techniques, and Tools2008-01-01 Georgia Institute of Technology
  In a packet network, the terms "Bandwidth" or "Throughput" often characterize the amount of data that the network can transfer per unit of time. Bandwidth estimation is of interest to users wishing to optimize end-to-end transport performance, overlay network routing, and peer-to-peer file distribution. Techniques for accurate bandwidth estimation are also important for traffic engineering and capacity planning support. Existing bandwidth estimation tools measure one or more of three related metrics: capacity, available bandwidth, and Bulk Transfer Capacity (BTC). Currently available bandwidth estimation tools employ a variety of strategies to measure these metrics. This survey reviews the recent bandwidth estimation literature focusing on underlying techniques and methodologies as well as open source bandwidth measurement tools.

Tags: TCP - IP		   
whitepaper ABwE: A Practical Approach to Available Bandwidth Estimation2008-01-01 Stanford University
  This paper reports on a new tool developed for monitoring available bandwidth in the range from several Mbps to 1000 Mbps. The tool is based on the packet pair dispersion technique. It has been in experimental use at SLAC for several months and it has been demonstrated at iGrid2002 and SC2002. It can be used for detecting bandwidth changes caused by routing or congestions. This paper has studied the influence of cross traffic and the behavior of routers on the delay of the probing packets. The paper presents part of these analyses together with results from monitoring of 12 paths in US, Japan and in Europe.

Tags: TCP - IP