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International Conference on signal, Image, Vision and their Applications (SIVA )

作者： Yacine Harkat Abderrahmane Amrouche Division Microélectronique et Nanotechnologie (DMN) Centre de Développement des Technologies Avancées (CDTA) Speech Com. Signal Proc. Lab. FEI USTHB Cité 20 août 1956 Baba Hassen Algiers Algeria Speech Communication and Signal Processing Laboratory Faculty of Electronics and Computer Sciences USTHB P.O. Box 32 El Alia Bab Ezzouar Algiers Algeria

ISBN: (纸本)9781538671214;9781538671207

Vehicular ad-hoc networks (VANETs) are considered as a key component of future Intelligent Transportation Systems (ITS). The IEEE 802.11p standard modifies the IEEE 802.11a to adapt to vehicular networks. In the MAC sublayer, the IEEE 802.11p standard uses Enhanced Distributed Channel Access (EDCA) mechanism to provide differentiated media access by defining four access categories (ACs). However, VANET characteristics such as network size, high speed, fast topology changes, traffic density, can greatly affect network performance, especially for the MAC sub-layer. Therefore, important issues arise about the ability of this standard to provide reliable and efficient services for vehicular environment. Since test beds are still limited, computer simulations are very useful for the automobile industry. This paper present a simulation-based analysis of the impact of the vehicle density, vehicle speed and packet inter-arrival time on the performance of the IEEE 802.11p EDCA mechanism in VANET. Throughput, average delay and packet delivery ratio (PDR) were considered as evaluation metrics. The obtained results confirm that IEEE 802.11p EDCA provides an effective differentiation service mechanism that can be adapted to critical ITS applications. However, we noted a performance degradation in extreme cases. As in large number of communicating vehicles, very high speeds, and high transmission rates.

关键词： Throughput Delays Standards Vehicular ad hoc networks Data models Mobile computing

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Turbulence mitigation scheme based on multiple-user detection in an orbital-angular-momentum multiplexed system

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Chinese Physics B 2016年第11期25卷 316-323页

作者：邹丽王乐赵生妹陈汉武 Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications School of Electronics and Information Nantong University Key Laboratory of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications School of Computer Science and Engineering College of Software Engineering Southeast University

Atmospheric turbulence（AT） induced crosstalk can significantly impair the performance of a free-space optical（FSO）communication link using orbital angular momentum（OAM） *** this paper,we propose a multiple-user detection（MUD） turbulence mitigation scheme in an OAM-multiplexed FSO communication ***,we present a MUD equivalent communication model for an OAM-multiplexed FSO communication link under *** the equivalent model,each input bit stream represents one user＇s *** deformed OAM spatial modes caused by AT,instead of the pure OAM spatial modes,are used as information carriers,and the overlapping between the deformed OAM spatial modes are computed as the correlation coefficients between the ***,we present a turbulence mitigation scheme based on MUD idea to enhance AT tolerance of the OAM-multiplexed FSO communication *** the proposed scheme,the crosstalk caused by AT is used as a useful component to deduce users＇ *** numerical results show that the performance of the OAM-multiplexed communication link has greatly improved by the proposed *** the turbulence strength C_n^2 is 1 × 10^（-15） m^（-2/3）,the transmission distance is 1000 m and the channel signal-to-noise ratio（SNR）is 26 dB,the bit-error-rate（BER） performance of four spatial multiplexed OAM modes l_m = ＋ 1,＋2,＋3,＋4 are all close to 10-5,and there is a 2-3 fold increase in the BER performance in comparison with those results without the proposed *** addition,the proposed scheme is more effective for an OAM-multiplexed FSO communication link with a larger OAM mode topological charge *** proposed scheme is a promising direction for compensating the interference caused by AT in the OAM-multiplexed FSO communication link.

关键词： turbulence mitigation momentum angular deformed crosstalk topological multiplexing orbital turbulent

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Semi-automated extraction of retinal blood vessel network with Bifurcation and crossover points 12th

Semi-automated extraction of retinal blood vessel network wi...

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12th International Symposium on Visual Computing, ISVC 2016

作者： Nougrara, Z. Kihal, N. Meunier, J. Faculty of Mathematics and Computer Science Department of Mathematics University of Sciences and Technology of Oran Oran Algeria Signal and Image Processing Laboratory Electronics and Computer Science Faculty USTHB Algiers Algeria Department of Computer Science and Operations Research University of Montreal Montreal Canada

ISBN: (纸本)9783319508313

Among different retinal analysis tasks, blood vessel extraction plays an important role as it is often the first essential step before any measurement can be made for various applications such as biometric authentication or diagnosis of retinal vascular diseases. In this paper, we present a new method for extraction of blood vessel network with its nodes (bifurcation and crossover points) from retinal images. The first step is to identify pixels with homogeneous vessel elements with a set of four directional filters. Then another step is applied to extract local linear components assuming that a vessel is a set of short linear segments. Through an optimization process this information is combined to extract the vessel network and its nodes. The proposed algorithm was tested on the publicly available DRIVE retinal fundus image database. The experimental results show good precision, recal. The proposed algorithm was tested on the publicly available DRIVE retinal fundus image database. The experimental results show good precision, recall and F-measure compared to ground truth and a state-of-the-art algorithm for the same dataset. © Springer International Publishing AG 2016.

关键词： Blood vessels

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5G ENTERING INTO A NEW ERA

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China communications 2017年第12期14卷 I0002-I0004页

作者： Feifei Gao Changle Li Jun Fang Kaizhi Huang Zhi Quan Chengwen Xing Jianhua Zhang Zhongshan Zhang Liqiang Zhao Yulong Zou Department of Automation Tsinqhua UniversityBeiiingChina the State Key Laboratory of Integrated Services Networks Xidian University china communications ieee communications magazine ieee signal processing letters national digital switching system engineering&technological research center the college of information engineering shenzhen university the school of information and electronics beijing institute of technology bupt itu-r imt-2020 channel model ieee comm the school of computer and communication engineering in the university of science and technology beijing(ustb) state key lab.of integrated ser vice networks xidian university the nanjing university of posts and telecommunications(nupt)

The ever increasing wireless data services, such asimaging, video, audio, multimedia, etc., have de-mands for the very high speed wireless communicationsand network, which are unfortunately a bottleneck whencombining with the wireline core network. Users＇ arenow expecting high quality of experience with low-costdevices, ubiquitous connectivity, energy efficiency, highreliability, or even ultra-low latency if a vehicle terminalis applied.

关键词： 5G ENTERING A NEW ERA

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Multimodal biometric system based on palmprint using progressive image compression

Multimodal biometric system based on palmprint using progres...

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International Conference on Information Technology for Organizations Development (IT4OD)

作者： Djamel Samai Abdallah Meraoumia Salim Chitroub Noureddine Doghmane Abdelmalik Taleb-Ahmed Faculté des Nouvelles Technologies de l'Information et de la Communication Laboratoire de Génie Électrique Ouargla Algérie Electronics and Computer Science Faculty Signal and Image Processing Laboratory Algiers Algeria Department of Electronics Badji Mokhtar University Annaba Algeria UMR University of Valenciennes France

In this paper, we propose a multimodal palmprint verification system based on two bands (gray scale and near infrared) using a progressive image compression through the famous Set Partitioning In Hierarchical Trees (SPIHT) coder. Each palmprint image is compressed an decompressed at 0.5 bit per pixel (bpp). By exploiting the progressiveness of the SPIHT algorithm, we decompressed the palmprint images in two bitrates. We obtained three images, an image at 0.25 bpp which represents the image approximation, the other at 0.25 bpp which represents the edges or details, and the third is the global of the both preceding. After analyzing the extracted features from different bands, we propose a score-level fusion scheme to integrate the multimodal information. The palmprint verification experiments demonstrated the superiority of multibands fusion to each single band, which results in higher verification accuracy.

关键词： Biometrics (access control) Feature extraction Image coding Databases Image resolution Authentication Bit rate

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Improving network echo cancellation in VoIP using Packet Loss Concealment 15

Improving network echo cancellation in VoIP using Packet Los...

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International Conference on Intelligent Information processing, Security and Advanced communication, IPAC 2015

作者： Hamidia, Mahfoud Bakri, Adil Amrouche, Abderrahmane Speech Communication and Signal Processing Laboratory LCPTS Faculty of Electronics and Computer Science USTHB B.P. 32 Bab-Ezzouar Algiers16111 Algeria Centre de Recherche Scientifique et Technique pour le Développement de Langue Arabe CRSTDLA D-Alger Algeria

ISBN: (纸本)9781450334587

This paper deals the problem of network echo in Voice over Internet Protocol (VoIP). Unfortunately, the presence of network echo due to the impedance mismatch in this network degrades the speech quality. Network Echo Canceller (NEC) based on adaptive filtering is generally used to remove this echo. Moreover, the performance of the NEC is dramatically degraded during Packet Loss (PL) situations in the VoIP network. In this work, we investigate a Packet Loss Concealment (PLC) method to improve the NEC performance in packet loss scenarios. This method consists of generating a synthetic speech signal to cover missing data in a received bit stream. Simulation results using speech signals issued from NOIZEUS dataset and echo path modeled by a sparse impulse response show a significant improvement in performance of NEC using PLC compared to NEC without PLC. © 2015 ACM.

关键词： Packet loss

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Corneal topography: An emerging biometric system for person authentication 14

Corneal topography: An emerging biometric system for person ...

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14th International Conference of the Biometrics Special Interest Group, BIOSIG 2015

作者： Kihal, Nassima Polette, Arnaud Chitroub, Salim Brunette, Isabelle Meunier, Jean Signal and Image Processing Laboratory Electronics Computer Science Faculty USTHB Algiers Algeria University of Montreal Canada Aix-Marseille University CNRS LSIS UMR 7296 France Maisonneuve-Rosemont Hospital Department of Ophthalmology University of Montreal Canada

ISBN: (纸本)9783885796398

Corneal topography is a non-invasive medical imaging technique to assess the shape of the cornea in ophthalmology. In this paper we demonstrate that in addition to its health care use, corneal topography could provide valuable biometric measurements for person authentication. To extract a feature vector from these images (topographies), we propose to fit the geometry of the corneal surface with Zernike polynomials, followed by a linear discriminant analysis (LDA) of the Zernike coefficients to select the most discriminating features. The results show that the proposed method reduced the typical d-dimensional Zernike feature vector (d=36) into a much lower r-dimensional feature vector (r=3), and improved the Equal Error Rate from 2.88% to 0.96%, with the added benefit of faster computation time. © 2015 Gesellschaft für Informatik e.V.

关键词： Topography

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Framework for VOIP speech database generation and a comparaison of different features extraction methodes for speaker identification on VOIP

Framework for VOIP speech database generation and a comparai...

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International Conference on Control, Engineering & Information Technology

作者： El-Taani Imen Amrous Anissa Imen Mohamed Debyeche Speech Communication and Signal Processing laboratory (LPCTS) Faculty of Electronics and Computer Sciences USTHB

ISBN: (纸本)9781479982134

This paper presents a framework for VOIP database generation and an investigation of the impact of VOIP characteristics on the accuracy of automatic speaker identification system. Exactly we study the impact of G711 and iLBC codec, and the influence of packet loss. A set of experiments are done on the generated databases to find the best feature extraction method for speaker identification on VOIP. The acoustic features considered are the most commonly used ones: MFCCs, LPCs and PLPs. Speaker models used in this study are based on Gaussian Mixture models and are implemented using HTK. VOIP databases used for training and testing are created using Asterisk.

关键词： Speaker identification VOIP GMM Asterisk MFCC LPC PLP

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Sign Language Recognition using PCA, Wavelet and Neural Network

Sign Language Recognition using PCA, Wavelet and Neural Netw...

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International Conference on Control, Engineering & Information Technology

作者： Khadidja SADEDDINE Fatma Zohra CHELALI Rachida DJERADI Speech communication and signal processing laboratory Electronics and computer Science Faculty Houari Boumedienne University of sciences and Technologies USTHB

ISBN: (纸本)9781479982134

Deaf people all around the world use sign language to communicate and like oral languages vary from country to another so it is for the sign languages. In this paper, we propose a probabilistic neural network (PNN) for two Sign languages: American Sign Language (ASL) recognition for static signs and Arabic sign Language. The signs in both of them are realized with one naked hand and simple background. DCT, DWT and PCA for spatial reduction method. Although PCA has been used before in sign language as a dimensionality reduction technique, it is used here as a descriptor that represents a global image feature. Finally we combine the features to improve the recognition rate (RR) and an error rate (ER) where DWT combined with the PCA using PNN classifier achieves RR 80.2% and ER 3.90% for Arabic database. The RR is improved to be 94% for American database with an ER 1.2%.

关键词： Sign Language Recognition DCT PCA DWT Neural network

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Sum-Rate and Power Scaling of Massive MIMO Systems with Channel Aging

Sum-Rate and Power Scaling of Massive MIMO Systems with Chan...

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作者： Kong, Chuili Zhong, Caijun Papazafeiropoulos, Anastasios K. Matthaiou, Michail Zhang, Zhaoyang Institute of Information and Communication Engineering Zhejiang University Hangzhou310027 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Department of Communications and Signal Processing Group Imperial College London London United Kingdom School of Electronics Electrical Engineering and Computer Science Queen's University Belfast Belfast United Kingdom

This paper investigates the achievable sum-rate of massive multiple-input multiple-output (MIMO) systems in the presence of channel aging. For the uplink, by assuming that the base station (BS) deploys maximum ratio combining (MRC) or zero-forcing (ZF) receivers, we present tight closed-form lower bounds on the achievable sum-rate for both receivers with aged channel state information (CSI). In addition, the benefit of implementing channel prediction methods on the sum-rate is examined, and closed-form sum-rate lower bounds are derived. Moreover, the impact of channel aging and channel prediction on the power scaling law is characterized. Extension to the downlink scenario and multicell scenario is also considered. It is found that, for a system with/without channel prediction, the transmit power of each user can be scaled down at most by 1/√M (where M is the number of BS antennas), which indicates that aged CSI does not degrade the power scaling law, and channel prediction does not enhance the power scaling law;instead, these phenomena affect the achievable sum-rate by degrading or enhancing the effective signal to interference and noise ratio, respectively. © 2015 IEEE.

关键词： Channel state information

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