Circuit Emulation over IP Networks

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Empirical models have limited accuracy for coupled mixture-environment-geometry-time effects on concrete drying shrinkage. An interpretable machine-learning framework was developed using 42,099 records from the NU Shrinkage-Creep Database, benchmarking nine algorithms under Bayesian optimization and four metaheuristics. GA-LightGBM achieved the best performance, with an RMSE 78.4% lower than GL2000. Bayesian optimization favored GBDT and CatBoost whereas PSO favored MLP, RF, and AdaBoost. SHAP analysis iden

Network coding permits to deploy distributed packet delivery algorithms that locally adapt to the network availability in media streaming applications. However, it may also increase delay and computational complexity if it is not implemented efficiently. We address here the effective placement of nodes that implement randomized network coding in overlay networks, so that the goodput is kept high while the delay for decoding stays small in streaming applications. We first estimate the decoding delay at each

This paper presents a novel concept of semi-autonomous navigation where a mobile robot evolves autonomously under the monitoring of a human user. The user provides corrective commands to the robot whenever he disagrees with the robot's navigational choices. These commands are not related to navigational values like directions or goals, but to the relevance of the robot's actions to the overall task. A binary error signal is used to correct the robot's decisions and to bring it to the desired goal location.

Biometric authentication is a process of verifying an identity claim using a person's behavioral and physiological characteristics. This is in general a binary classification task because a system either accepts or rejects an identity claim. However, a biometric authentication system contains many users. By recognizing this fact, better decision can be made if user-specific information can be exploited. In this study, we propose to combine user-specific information with user-independent information such tha

We review the structural, electronic and dielectric properties of atomistic models of the Si(100)-SiO2 interface, which have been purposely designed in order to match a large variety of atomic-scale experimental data. After describing the generation procedure and the structural properties of two specific interface models, we study the corresponding electronic structure and dielectric response within the framework of density-functional theory. Particular emphasis is given to a systematic comparison between t

This paper presents an evaluation of the benefits and user acceptance of a multimodal interface in which the user interacts with a game-like interactive virtual reality application "The Enigma of the Sphinx". The interface consists of a large projection screen as the main display, a "magic wand", a stereo sound system and the user's voice for "casting spells". We present our conclusions concerning "friendliness" and sense of presence, based on observations of more than 150 users in a public event

Thermo-optical and electro-optical (plasma dispersion) effects for silicon based integrated optical modulators are becoming attractive and effective solutions for telecommunications applications such as switching for programmable optical add-drop multiplexing for WDM. In this paper, a simple yet highly efficient novel electro-optical modulator device that exploits a SOI Schottky diode integrated in silicon rib wave-guide is proposed. Numerical 2D electrical (ATLAS©1) and 3D optical (BPM_CAD©2)simulations ar

The literature contains propositions for the use of overlay networks to supplement the normal IP routing functions with higher-level information in order to improve aspects of network behavior. We consider the use of such an overlay to optimize the end-to-end behavior of some special tra c ows. Measurements are used both to construct the virtual links of the overlay and to establish the link costs for use in a link-state routing protocol. The overlay attempts to forward certain packets over the least conges

Current TCP-friendly congestion control mechanisms such as those used in TFRC adjust the packet rate in order to adapt to network conditions and obtain a throughput not exceeding that of a TCP connection operating under the same conditions. In an environment where the bottleneck resource is packet processing, this is the correct behavior. However, if the bottleneck resource is bandwidth, and flows may use packets of different sizes, resource sharing then depends on packet size and is no longer fair. Now for

The success of new service provision platforms will largely depend on their ability to blend with existing technologies. The advent of Internet telephony, although impressive, is unlikely to make telephone customers suddenly turn in favor of computers. Rather, customers display increasing interest in services that span multiple networks (especially Internet Protocol-based networks and the telephone and cellular networks) and open new vistas. We refer to these services as hybrid services and propose an archi

A single failure in a communication network may trigger many alarms. When the communication network uses optical fibres as transmission medium and increases its capacity by using Wavelength Division Multiplexing (WDM), the number of alarms and the difficulty to locate the failure are considerably higher. In this case, a single failure may interrupt several channels which causes a large information loss. We propose an Alarm Filtering Algorithm (AFA) for the fault management of an optical network that support

We address the problem of time-base synchronization for MPEG services in the presence of network jitter. The conventional methods to obtain a stable clock indication are based on Phase Locked Loops (PLLs). They have the disadvantage of a long startup phase, therefore being unsuitable for services that require simultaneous accuracy and rapidity. We develop a new time-base synchronization technique based on a Least-square Linear Regression algorithm (LLR). We show that LLR is able to perform time-base synchro

There is a wide consensus that an object explicitly embodies an abstraction, but the exact meaning of this statement is not necessarily well understood. This paper argues that the abstraction embodied by an object (or a component) implementation is nothing else than its specification. This implies that abstrac-tion does not appear automatically, it must be carefully constructed and maintained. The paper goes on to show, with the support of an example, that defining contracts for an objects operations does n

In robotics we depend on software tools during design, modeling, programming and testing. These tools are essentials, often indispensable aids for developing and operating sophisticated robotic systems. At the same time, these tools are complex and usually too difficult to be used by non specialists. For example tools used for simulation or off-line programming require significant knowledge and skill. The goal of this thesis is to provide novice users with an intuitive tool (CINEGEN) for designing, studying

Current resource reservation architectures for multimedia networks do not scale well for a large number of flows. We propose a new architecture that automatically aggregates flows on each link in the network. Therefore, the network has no knowledge of individual flows. There is no explicit signalling protocol, and the protocol overhead mainly consists in the introduction of a packet type with three values (reserved, request or best-effort) which can be encoded on two bits. Keywords: Resource reservation, In

Giving users simple access to QoS selection capability of ATM networks is important for the future of integrated services networks. We describe the first instance of an application in which users had the capacity to tune ATM traffic parameters with a button, at run time. To achieve this we implemented the necessary signaling extension on ATM switches as well as on end-systems. Furthermore, we extended Arequipa (Application REQested IP over ATM; a mechanism that enables applications to request direct ATM con

We analyse and illustrate two approaches that we have developed for providing reservations to flows. The first approach uses the explicit reservation model: a traffic profile is negotiated between users and the network. ATM and RSVP are two examples for this approach. In this paper we describe our experience in the ACT project EXPERT (AC094) with the explicit reservation model in the context of ATM. We show that the integration of ATM in a TCP/IP oriented operating system is easy and does not require develo

Routing as well as the management of communication networks that support hybrid types of communications requiring quality of service is a hard problem. We present here a framework1 that decomposes the network into a hierarchy of abstract views of the network that summarizes the available bandwidth resources and highlights bottlenecks in the network in order to reduce the complexity of the previously mentioned tasks. This framework can easily be distributed to a hierarchy of intelligent agents. This framewor

A single failure in a communication network can trigger many alarms. We propose an alarm filtering algorithm for the management of an optical network using Wavelength Division Multiplexing (WDM). The algorithm supports: (i) multiple failures and (ii) passive network elements that do not generate alarms but may fail. This algorithm will be applied to the network of the ACTS COBNET project.

We use recent network calculus results to study some properties of lossless multiplexing as it may be used in guaranteed service networks. We call network calculus a set of results that apply min-plus algebra to packet networks. We provide a simple proof that shaping a traffic stream to conform with a burstiness constraint preserves the original constraints satisfied by the traffic stream We show how all rate based packet schedulers can be modeled with a simple rate latency service curve. Then we define a g

Circuit Emulation over IP Networks

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Matching metaheuristics to machine learning for concrete drying shrinkage prediction toward cost-effective mix design

Selection of Network Coding Nodes for Minimal Playback Delay in Streaming Overlays

Bayesian Controller for a Novel Semi-Autonomous Navigation Concept

Compensating User-Specific Information with User-Independent Information in Biometric Authentication Tasks

Atomistic models of the Si(100)-SiO2 interface: structural, electronic and dielectric properties

Magic wand and the Enigma of the Sphinx

A Novel SOI Schottky Electro-optical Modulator for Ghz High-Speed Switching

The Performance of Measurement-Based Overlay Networks

End-to-end Congestion Control for Flows with Variable Packet Size

A programmable architecture for the provision of hybrid services

Fault Localization at the WDM layer

Clock synchronization of MPEG-2 services over packet networks

On the Abstraction of Objects, Components and Interfaces

Interface pour le pilotage et l'analyse des robots basée sur un générateur de cinématiques

SRP: a Scalable Resource Reservation Protocol for the Internet

Quality of Service Renegotiations

Reservation Models, From Arequipa to SRP

A Dynamic Hierarchy of Intelligent Agents for Network Management

An Alarm Filtering Algorithm for Optical Communication Networks

Application of Network Calculus to Guaranteed Service Networks