Search results for "Networking & Telecommunications"

Human-in-the-Loop Conversation Agent for Customer Service

2020

This paper describes a prototype system for partial automation of customer service operations of a mobile telecommunications operator with a human-in-the loop conversational agent. The agent consists of an intent detection system for identifying the types of customer requests that it can handle appropriately, a slot filling information extraction system that integrates with the customer service database for a rule-based treatment of the common scenarios, and a template-based language generation system that builds response candidates that can be approved or amended by customer service operators. The main focus of this paper is on the system architecture and machine learning system structure …

TCP Performance in Mobile Ad hoc Networks

2013

International audience; In this paper, we present a survey of TCP (Transmission Control Protocol) protocol for better performance in the MANET (Mobile Ad Hoc Network). After a short presentation of the main features of TCP, we give the most important problems from which TCP suffer in MANET. We present after that some approaches proposed in the literature in order to improve its performance. Our paper contains also a performance evaluation of TCP NewReno and TCP Vegas transport protocols under AODV and DSR routing protocols. The simulations are conducted under varying conditions of number of TCP connections, number of nodes and mobility.

Cadmium mass measurements between the neutron shell closures at N=50 and 82

2010

International audience; The mass values of the neutron-deficient cadmium isotopes 99−109Cd and of the neutronrich isotopes 114,120,122−124,126,128Cd have been measured using ISOLTRAP. The behavior of the separation energies of the cadmium isotopes from N = 50 to 82 is discussed.

Improving Communication in Risk Management of Health Information Technology Systems by means of Medical Text Simplification

2019

Health Information Technology Systems (HITS) are increasingly used to improve the quality of patient care while reducing costs. These systems have been developed in response to the changing models of care to an ongoing relationship between patient and care team, supported by the use of technology due to the increased instance of chronic disease. However, the use of HITS may increase the risk to patient safety and security. While standards can be used to address and manage these risks, significant communication problems exist between experts working in different departments. These departments operate in silos often leading to communication breakdowns. For example, risk management stakeholder…

On the spectral moments of non-WSSUS mobile-to mobile double-Rayleigh fading channels

2017

This paper deals with the mathematical analysis of the spectral moments of non-wide-sensestationary uncorrelated-scattering (non-WSSUS) mobile-to-mobile (M2M) double-Rayleigh fading channels. The point of departure is a recently proposed geometry-based statistical model (GBSM) for M2M double-Rayleigh fading channels from which general analytical expressions are derived for the average Doppler shift, Doppler spread, average delay, and delay spread. Closed-form solutions of such expressions are presented for the particular case of the geometrical two-rings scattering model. The obtained results indicate that the average Doppler shift and Doppler spread are directly influenced by not only the …

An Adaptive Combination of Dark and Bright Channel Priors for Single Image Dehazing

2017

Dehazing methods based on prior assumptions derived from statistical image properties fail when these properties do not hold. This is most likely to happen when the scene contains large bright areas, such as snow and sky, due to the ambiguity between the airlight and the depth information. This is the case for the popular dehazing method Dark Channel Prior. In order to improve its performance, the authors propose to combine it with the recent multiscale STRESS, which serves to estimate Bright Channel Prior. Visual and quantitative evaluations show that this method outperforms Dark Channel Prior and competes with the most robust dehazing methods, since it separates bright and dark areas and …

Channel aggregation with guard-band in D-OFDM based CRNs: Modeling and performance evaluation

2016

Channel aggregation (CA) techniques can offer flexible channel allocation and improve overall system performance in multi-channel cognitive radio networks (CRNs). Although many CA techniques have been proposed and studied, the impact of guard-band on CA for channel access has not been addressed in-depth. In this paper, we study the guard-band allocation mechanisms in discontinuous-orthogonal frequency division multiplexing (D-OFDM) based CRNs, and investigate the impact of guard-band sharing on SU flows when CA is enabled. Continuous time Markov chain (CTMC) based models have been developed in order to investigate the stochastic behavior of PU and SU flows. Based on our mathematical analysi…

Underlay Device-to-Device Communications on Multiple Channels

2018

Author´s accepted manuscript (postprint). © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Since the spectral efficiency of wireless communications is already close to its fundamental bounds, a significant increase in spatial efficiency is required to meet future traffic demands. Device-to-device (D2D) communications provide such an increase by allowing nearby u…

An Investigation of Security and Privacy for Human Bond Communications

2017

ROS/Gazebo Based Simulation of Co-operative UAVs

2019

UAVs can be assigned different tasks such as e.g., rendez-vous and space coverage, which require processing and communication capabilities. This work extends the architecture ROS/Gazebo with the possibility of simulation of co-operative UAVs. We assume UAV with the underlying attitude controller based on the open-source Ardupilot software. The integration of the co-ordination algorithm in Gazebo is implemented with software modules extending Ardupilot with the capability of sending/receiving messages to/from drones, and executing the co-ordination protocol. As far as it concerns the simulation environment, we have extended the world in Gazebo to hold more than one drone and to open a specif…