In this paper, we describe the Adaptive Multi-Rate (AMR) speech coder currently under standardization for GSM systems as part of the AMR speech service. The coder is a multi-rate ACELP coder with 8 modes operating at bit-rates from 12.2 kbit/s down to 4.75 kbitls. The coder modes are integrated in a common structure where the bit-rate scalability is realized mainly by altering the quantization ...

The objective of recent research in fair queueing schemes has been to efficiently emulate a fluid-flow generalized (weighted) processor sharing (GPS) system, as closely as possible. A primary motivation for the use of fair-queueing has been its use as a means of providing bandwidth guarantees and as a consequence end-to-end delay bounds for traffic with bounded burstiness. The rate guarantees t...

An increasing number of real-time applications, related to multimedia and adaptive control systems, require greater flexibility than classical real-time theory usually permits. In this paper we present a novel periodic task model, in which tasks’ periods are treated as springs, with given elastic coefficients. Under this framework, periodic tasks can intentionally change their execution rate to...

An adaptive coding scheme is introduced for a discrete sequence code-division multiple-access system. The system uses noncoherentM -ary orthogonal modulation with RAKE receiver and power control. Both a fast fading channel and a combined fast fading, shadowing and power control channel are considered. Analytical bounds and simulations are done to evaluate the performance of the system. It is fo...

Next-generation sequencing technology allows the identification of molecular changes that have arisen in the genomes of microorganisms undergoing experimental evolution. This permits the elucidation of the molecular evolutionary dynamics in these populations.