A flow-based approach to modeling ADSL traffic on an IP backbone link

Measurements from an Internet backbone link carryingtcp traffic towards differentadsl areas are analyzed in this paper. For traffic analysis, we adopt a flow-based approach and the popular mice/elephants dichotomy. The originality of the experimental data reported in this paper, when compared with previous measurements from very high speed backbone links, is that commercial traffic comprises a significant part due to peer-to-peer applications. This kind of traffic exhibits some remarkable properties in terms of mice, elephants and bit rates, which are thoroughly described in this paper. Global traffic is actually decomposed into several flow components on the basis of the mice/elephants dichotomy. Mice due p2p protocols and mice due to classical Internet applications such ashttp, ftp, etc. are analyzed separately. It turns out that by adopting a suitable level of aggregation, global traffic can be described by means of usual tele-traffic models based on M/G/∞ queues with Weibullian service times. The blobal bit rate can then be approximated by the superposition of Gaussian processes perturbed by a white noise.     

Magnetic Analysis of Supersonic Beams of Atomic Oxygen,Nitrogen, and Chlorine Generated from a Radio-Frequency Discharge

Supersonic beams of oxygen, nitrogen, and chlorine atoms and of metastable oxygen and nitrogen molecules produced from a high-pressure radio-frequency discharge beam source have been characterized by coupling velocity selection with magnetic analysis in the transmission mode. The present work leads to the determination of the relative populations of the electronic states of the species in the produced beams, showing that estimates of the populations from plasma temperatures or final translational temperatures could bring on incorrect conclusions.     

A Flexible Architecture for Virtual Humans in Networked Collaborative Virtual Environments

Complex virtual human representation provides more natural interaction and communication among participants in networked virtual environments, hence it is expected to increase the sense of being together within the same virtual world. We present a flexible framework for the integration of virtual humans in networked collaborative virtual environments. A modular architecture allows flexible representation and control of the virtual humans, whether they are controlled by a physical user using all sorts of tracking and other devices, or by an intelligent control program turning them into autonomous actors. The modularity of the system allows for fairly easy extensions and integration with new techniques making it interesting also as a testbed for various domains from “classic” VR to psychological experiments. We present results in terms of functionalities, example applications and measurements of performance and network traffic with an increasing number of participants in the simulation.     

The use of indirect memory tests to assess malingered amnesia: A study of metamemory.

Many techniques have been suggested for identifying criminal suspects who are simulating amnesia for events surrounding a crime. The present research focuses on indirect memory tests as a potential means of discriminating between those who genuinely suffer from amnesia and those who are simulating. Ss studied a list of words and subsequently performed either a word completion or a fragment completion task. Under normal indirect test instructions, typical priming effects were observed. When Ss were motivated to simulate amnesia for the list, target completion rates were consistently, and sometimes reliably, below baseline completion rates. This finding is contrary to the performance of genuine amnesics, whose performance on indirect tests typically mirrors that of normal Ss. Indirect tests may prove useful in discriminating genuine and simulating amnesics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Choosing an implementation language for Automatic Translation

The purpose of this paper is to analyze the major characteristics of the implementation language for very large portable software packages and to identify the most suitable programming languages for Automatic Translation. Criteria such as Portability, Modularity, Reliability, Human Factors, Technical Richness, Performance and Adaptability are analyzed.

Four programming languages (PASCAL, C, FORTRAN 77 and ADA) are selected. The advantages and disadvantages of each of the four programming languages are studied according to the criteria presented above.     

Stop-and-go cloth draping

The aim of cloth draping is to compute the rest state of a piece of cloth, possibly in contact with other solid objects, as quickly as possible. The context of free motion and very large deformations specific to cloth simulation makes the usual energy minimization schemes traditionally used in mechanical engineering inefficient. Therefore, most cloth draping applications only rely on dynamic simulation with ad hoc viscous damping or the dissipative behavior of numerical integration methods for obtaining convergence to the rest position of the cloth. We propose a “stop-and-go” technique which cuts out the velocity of the object at particular times for converging to the rest state, while taking advantage of the natural cloth motion toward equilibrium. This scheme can very easily complement any existing dynamical cloth simulation system, using either implicit or explicit numerical integration methods.     

Automatic accurate broken character restoration for patrimonial documents

In this article, we are interested in the restoration of character shapes in antique document images. This particular class of documents generally present a lot of involuntary historical information that have to be taken into account to get quality digital libraries. Actually, many document processing methods of all sorts have already been proposed to cope with degraded character images, but those techniques often consist in replacing the degraded shapes by a corresponding prototype which is not satisfying for lots of specialists. For that, we decided to develop our own method for accurate character restoration, basing our study on generic image processing tools (namely: Gabor filtering and the active contours model) completed with some specific automatically extracted structural information. The principle of our method is to make an active contour recover the lost information using an external energy term based on the use of an automatically built and selected reference character image. Results are presented for real case examples taken from printed and handwritten documents.